Cancer 'survivor-care': II. Disruption of prefrontal brain activation top-down control of working memory capacity as possible mechanism for chemo-fog/brain (chemotherapy-associated cognitive impairment).

PubMed

Raffa, R B

2013-08-01

Cancer chemotherapy-associated cognitive impairments (termed 'chemo-fog' or 'chemo-brain'), particularly in memory, have been self-reported or identified in cancer survivors previously treated with chemotherapy. Although a variety of deficits have been detected, a consistent theme is a detriment in visuospatial working memory. The parietal cortex, a major site of storage of such memory, is implicated in chemotherapy-induced damage. However, if the findings of two recent publications are combined, the (pre)frontal cortex might be an equally viable target. Two recent studies, one postulating a mechanism for 'top-down control' of working memory capacity and another visualizing chemotherapy-induced alterations in brain activation during working memory processing, are reviewed and integrated. A computational model and the proposal that the prefrontal cortex plays a role in working memory via top-down control of parietal working memory capacity is consistent with a recent demonstration of decreased frontal hyperactivation following chemotherapy. Chemotherapy-associated impairment of visuospatial working memory might include the (pre)frontal cortex in addition to the parietal cortex. This provides new opportunity for basic science and clinical investigation. © 2013 John Wiley & Sons Ltd.

Cortical thickness and prosocial behavior in school-age children: A population-based MRI study.

PubMed

Thijssen, Sandra; Wildeboer, Andrea; Muetzel, Ryan L; Bakermans-Kranenburg, Marian J; El Marroun, Hanan; Hofman, Albert; Jaddoe, Vincent W V; van der Lugt, Aad; Verhulst, Frank C; Tiemeier, Henning; van IJzendoorn, Marinus H; White, Tonya

2015-01-01

Prosocial behavior plays an important role in establishing and maintaining relationships with others and thus may have important developmental implications. This study examines the association between cortical thickness and prosocial behavior in a population-based sample of 6- to 9-year-old children. The present study was embedded within the Generation R Study. Magnetic resonance scans were acquired from 464 children whose parents had completed the prosocial scale of the Strengths and Difficulties Questionnaire. To study the association between cortical thickness and prosocial behavior, we performed whole-brain surface-based analyses. Prosocial behavior was related to a thicker cortex in a cluster that covers part of the left superior frontal and rostral middle frontal cortex (p < .001). Gender moderated the association between prosocial behavior and cortical thickness in a cluster including the right rostral middle frontal and superior frontal cortex (p < .001) as well as in a cluster covering the right superior parietal cortex, cuneus, and precuneus (p < .001). Our results suggest that prosocial behavior is associated with cortical thickness in regions related to theory of mind (superior frontal cortex, rostral middle frontal cortex cuneus, and precuneus) and inhibitory control (superior frontal and rostral middle frontal cortex).

Attentional Control of Task and Response in Lateral and Medial Frontal Cortex: Brain Activity and Reaction Time Distributions

ERIC Educational Resources Information Center

Aarts, Esther; Roelofs, Ardi; van Turennout, Miranda

2009-01-01

It is unclear whether task conflict is reflected in the anterior cingulate cortex (ACC) or in more dorsal regions of the medial frontal cortex (MFC). When participants switch between tasks involving incongruent, congruent, and neutral stimuli, it is possible to examine both response conflict (incongruent vs. congruent) and task conflict (congruent…

Interhemispheric EEG differences in olfactory bulbectomized rats with different cognitive abilities and brain beta-amyloid levels.

PubMed

Bobkova, Natalia; Vorobyov, Vasily; Medvinskaya, Natalia; Aleksandrova, Irina; Nesterova, Inna

2008-09-26

Alterations in electroencephalogram (EEG) asymmetry and deficits in interhemispheric integration of information have been shown in patients with Alzheimer's disease (AD). However, no direct evidence of an association between EEG asymmetry, morphological markers in the brain, and cognition was found either in AD patients or in AD models. In this study we used rats with bilateral olfactory bulbectomy (OBX) as one of the AD models and measured their learning/memory abilities, brain beta-amyloid levels and EEG spectra in symmetrical frontal and occipital cortices. One year after OBX or sham-surgery, the rats were tested with the Morris water paradigm and assigned to three groups: sham-operated rats, SO, and OBX rats with virtually normal, OBX(+), or abnormal, OBX(-), learning (memory) abilities. In OBX vs. SO, the theta EEG activity was enhanced to a higher extent in the right frontal cortex and in the left occipital cortex. This produced significant interhemispheric differences in the frontal cortex of the OBX(-) rats and in the occipital cortex of both OBX groups. The beta1 EEG asymmetry in SO was attenuated in OBX(+) and completely eliminated in OBX(-). OBX produced highly significant beta2 EEG decline in the right frontal cortex, with OBX(-)>OBX(+) rank order of strength. The beta-amyloid level, examined by post-mortem immunological DOT-analysis in the cortex-hippocampus samples, was about six-fold higher in OBX(-) than in SO, but significantly less (enhanced by 82% vs. SO) in OBX(+) than in OBX(-). The involvement of the brain mediatory systems in the observed EEG asymmetry differences is discussed.

[Effects of the removal of the orbito-frontal cortex on the development of reflex analgesia].

PubMed

Reshetniak, V K; Kukushkin, M L

1989-07-01

The authors studied the effect of electric acupuncture stimulation (EAP) on the changes in pain thresholds prior to and after removal of the orbito-frontal cortex (OFC) of the brain in behavioral experiments on adult cats. Removal of OFC increased the thresholds of pain response at the 4th and the 5th levels of the conventional scale, reflecting emotionally-affective manifestations of pain, and intensified the effect of antinociceptive EAP. The results obtained are analysed in relation to the inhibitory tonic effect of OFC on antinociceptive structures of the brain. Different effects of OFC and somatosensory cortex on the antinociceptive structures of the brain are discussed.

Changes in acetylcholinesterase, Na+,K+-ATPase, and Mg2+-ATPase activities in the frontal cortex and the hippocampus of hyper- and hypothyroid adult rats.

PubMed

Carageorgiou, Haris; Pantos, Constantinos; Zarros, Apostolos; Stolakis, Vasileios; Mourouzis, Iordanis; Cokkinos, Dennis; Tsakiris, Stylianos

2007-08-01

The thyroid hormones (THs) are crucial determinants of normal development and metabolism, especially in the central nervous system. The metabolic rate is known to increase in hyperthyroidism and decrease in hypothyroidism. The aim of this work was to investigate how changes in metabolism induced by THs could affect the activities of acetylcholinesterase (AChE), (Na+,K+)- and Mg2+-adenosinetriphosphatase (ATPase) in the frontal cortex and the hippocampus of adult rats. Hyperthyroidism was induced by subcutaneous administration of thyroxine (25 microg/100 g body weight) once daily for 14 days, and hypothyroidism was induced by oral administration of propylthiouracil (0.05%) for 21 days. All enzyme activities were evaluated spectrophotometrically in the homogenated brain regions of 10 three-animal pools. A region-specific behavior was observed concerning the examined enzyme activities in hyper- and hypothyroidism. In hyperthyroidism, AChE activity was significantly increased only in the hippocampus (+22%), whereas Na+,K+-ATPase activity was significantly decreased in the hyperthyroid rat hippocampus (-47%) and remained unchanged in the frontal cortex. In hypothyroidism, AChE activity was significantly decreased in the frontal cortex (-23%) and increased in the hippocampus (+21%). Na+,K+-ATPase activity was significantly decreased in both the frontal cortex (-35%) and the hippocampus (-43%) of hypothyroid rats. Mg2+-ATPase remained unchanged in the regions of both hyper- and hypothyroid rat brains. Our data revealed that THs affect the examined adult rat brain parameters in a region- and state-specific way. The TH-reduced Na+,K+-ATPase activity may increase the synaptic acetylcholine release and, thus, modulate AChE activity. Moreover, the above TH-induced changes may affect the monoamine neurotransmitter systems in the examined brain regions.

Regional distribution of neuropeptide Y mRNA in postmortem human brain.

PubMed

Brené, S; Lindefors, N; Kopp, J; Sedvall, G; Persson, H

1989-12-01

The distribution of messenger RNA encoding neuropeptide Y (NPY) was studied in 11 different postmortem human brain regions using in situ hybridization histochemistry, and RNA blot analysis. In situ hybridization data revealed that the highest numerical density of labeled cells corresponded to neurons in accumbens area, caudate nucleus, putamen, and substantia innominata. Significantly fewer NPY mRNA-containing neurons were found in frontal and parietal cortex, amygdaloid body and dentate gyrus. No NPY mRNA-containing cells were found in substantia nigra. NPY mRNA-positive neurons from all regions studied showed relatively similar labeling, as revealed by computerized image analysis. Blot analysis showed an approximately 0.8 kb NPY mRNA in all brain regions studied, except in substantia nigra and cerebellum. Densitometric scanning of the autoradiograms revealed levels of NPY mRNA in the following order: putamen greater than caudate nucleus greater than frontal cortex (Brodmann areas 4 and 6) greater than temporal cortex (Brodmann area 38) greater than parietal cortex (Brodmann areas 5 and 7) greater than frontal cortex (Brodmann area 11). Hence, although NPY mRNA is widely distributed in neurons of the human brain large regional variation exists, with the highest expression in accumbens area and parts of the basal ganglia.

Dynamic Variation in Pleasure in Children Predicts Nonlinear Change in Lateral Frontal Brain Electrical Activity

ERIC Educational Resources Information Center

Light, Sharee N.; Coan, James A.; Frye, Corrina; Goldsmith, H. Hill; Davidson, Richard J.

2009-01-01

Individual variation in the experience and expression of pleasure may relate to differential patterns of lateral frontal activity. Brain electrical measures have been used to study the asymmetric involvement of lateral frontal cortex in positive emotion, but the excellent time resolution of these measures has not been used to capture…

Co-localisation of abnormal brain structure and function in specific language impairment

PubMed Central

Badcock, Nicholas A.; Bishop, Dorothy V.M.; Hardiman, Mervyn J.; Barry, Johanna G.; Watkins, Kate E.

2012-01-01

We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior frontal cortex and decreased in the right caudate nucleus and superior temporal cortex bilaterally. The unaffected siblings also showed reduced grey matter in the caudate nucleus relative to controls. In an auditory covert naming task, the SLI group showed reduced activation in the left inferior frontal cortex, right putamen, and in the superior temporal cortex bilaterally. Despite spatially coincident structural and functional abnormalities in frontal and temporal areas, the relationships between structure and function in these regions were different. These findings suggest multiple structural and functional abnormalities in SLI that are differently associated with receptive and expressive language processing. PMID:22137677

Fetal Alcohol Spectrum Disorder-associated depression: evidence for reductions in the levels of brain-derived neurotrophic factor in a mouse model

PubMed Central

Caldwell, Kevin K.; Sheema, S.; Paz, Rodrigo D; Samudio-Ruiz, Sabrina L.; Laughlin, Mary H.; Spence, Nathan E.; Roehlk, Michael J; Alcon, Sara N.; Allan, Andrea M.

2009-01-01

Prenatal ethanol exposure is associated with an increased incidence of depressive disorders in patient populations. However, the mechanisms that link prenatal ethanol exposure and depression are unknown. Several recent studies have implicated reduced brain-derived neurotrophic factor (BDNF) levels in the hippocampal formation and frontal cortex as important contributors to the etiology of depression. In the present studies, we sought to determine whether prenatal ethanol exposure is associated with behaviors that model depression, as well as with reduced BDNF levels in the hippocampal formation and/or medial frontal cortex, in a mouse model of fetal alcohol spectrum disorder (FASD). Compared to control adult mice, prenatal ethanol-exposed adult mice displayed increased learned helplessness behavior and increased immobility in the Porsolt forced swim test. Prenatal ethanol exposure was associated with decreased BDNF protein levels in the medial frontal cortex, but not the hippocampal formation, while total BDNF mRNA and BDNF transcripts containing exon III, IV or VI were reduced in both the medial frontal cortex and the hippocampal formation of prenatal ethanol-exposed mice. These results identify reduced BDNF levels in the medial frontal cortex and hippocampal formation as potential mediators of depressive disorders associated with FASD. PMID:18558427

Frontal top-down signals increase coupling of auditory low-frequency oscillations to continuous speech in human listeners.

PubMed

Park, Hyojin; Ince, Robin A A; Schyns, Philippe G; Thut, Gregor; Gross, Joachim

2015-06-15

Humans show a remarkable ability to understand continuous speech even under adverse listening conditions. This ability critically relies on dynamically updated predictions of incoming sensory information, but exactly how top-down predictions improve speech processing is still unclear. Brain oscillations are a likely mechanism for these top-down predictions [1, 2]. Quasi-rhythmic components in speech are known to entrain low-frequency oscillations in auditory areas [3, 4], and this entrainment increases with intelligibility [5]. We hypothesize that top-down signals from frontal brain areas causally modulate the phase of brain oscillations in auditory cortex. We use magnetoencephalography (MEG) to monitor brain oscillations in 22 participants during continuous speech perception. We characterize prominent spectral components of speech-brain coupling in auditory cortex and use causal connectivity analysis (transfer entropy) to identify the top-down signals driving this coupling more strongly during intelligible speech than during unintelligible speech. We report three main findings. First, frontal and motor cortices significantly modulate the phase of speech-coupled low-frequency oscillations in auditory cortex, and this effect depends on intelligibility of speech. Second, top-down signals are significantly stronger for left auditory cortex than for right auditory cortex. Third, speech-auditory cortex coupling is enhanced as a function of stronger top-down signals. Together, our results suggest that low-frequency brain oscillations play a role in implementing predictive top-down control during continuous speech perception and that top-down control is largely directed at left auditory cortex. This suggests a close relationship between (left-lateralized) speech production areas and the implementation of top-down control in continuous speech perception. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Frontal Top-Down Signals Increase Coupling of Auditory Low-Frequency Oscillations to Continuous Speech in Human Listeners

PubMed Central

Park, Hyojin; Ince, Robin A.A.; Schyns, Philippe G.; Thut, Gregor; Gross, Joachim

2015-01-01

Summary Humans show a remarkable ability to understand continuous speech even under adverse listening conditions. This ability critically relies on dynamically updated predictions of incoming sensory information, but exactly how top-down predictions improve speech processing is still unclear. Brain oscillations are a likely mechanism for these top-down predictions [1, 2]. Quasi-rhythmic components in speech are known to entrain low-frequency oscillations in auditory areas [3, 4], and this entrainment increases with intelligibility [5]. We hypothesize that top-down signals from frontal brain areas causally modulate the phase of brain oscillations in auditory cortex. We use magnetoencephalography (MEG) to monitor brain oscillations in 22 participants during continuous speech perception. We characterize prominent spectral components of speech-brain coupling in auditory cortex and use causal connectivity analysis (transfer entropy) to identify the top-down signals driving this coupling more strongly during intelligible speech than during unintelligible speech. We report three main findings. First, frontal and motor cortices significantly modulate the phase of speech-coupled low-frequency oscillations in auditory cortex, and this effect depends on intelligibility of speech. Second, top-down signals are significantly stronger for left auditory cortex than for right auditory cortex. Third, speech-auditory cortex coupling is enhanced as a function of stronger top-down signals. Together, our results suggest that low-frequency brain oscillations play a role in implementing predictive top-down control during continuous speech perception and that top-down control is largely directed at left auditory cortex. This suggests a close relationship between (left-lateralized) speech production areas and the implementation of top-down control in continuous speech perception. PMID:26028433

Developmental synchrony of thalamocortical circuits in the neonatal brain.

PubMed

Poh, Joann S; Li, Yue; Ratnarajah, Nagulan; Fortier, Marielle V; Chong, Yap-Seng; Kwek, Kenneth; Saw, Seang-Mei; Gluckman, Peter D; Meaney, Michael J; Qiu, Anqi

2015-08-01

The thalamus is a deep gray matter structure and consists of axonal fibers projecting to the entire cortex, which provide the anatomical support for its sensorimotor and higher-level cognitive functions. There is limited in vivo evidence on the normal thalamocortical development, especially in early life. In this study, we aimed to investigate the developmental patterns of the cerebral cortex, the thalamic substructures, and their connectivity with the cortex in the first few weeks of the postnatal brain. We hypothesized that there is developmental synchrony of the thalamus, its cortical projections, and corresponding target cortical structures. We employed diffusion tensor imaging (DTI) and divided the thalamus into five substructures respectively connecting to the frontal, precentral, postcentral, temporal, and parietal and occipital cortex. T2-weighted magnetic resonance imaging (MRI) was used to measure cortical thickness. We found age-related increases in cortical thickness of bilateral frontal cortex and left temporal cortex in the early postnatal brain. We also found that the development of the thalamic substructures was synchronized with that of their respective thalamocortical connectivity in the first few weeks of the postnatal life. In particular, the right thalamo-frontal substructure had the fastest growth in the early postnatal brain. Our study suggests that the distinct growth patterns of the thalamic substructures are in synchrony with those of the cortex in early life, which may be critical for the development of the cortical and subcortical functional specialization. Copyright © 2015 Elsevier Inc. All rights reserved.

Visual assessment of brain magnetic resonance imaging detects injury to cognitive regulatory sites in patients with heart failure.

PubMed

Pan, Alan; Kumar, Rajesh; Macey, Paul M; Fonarow, Gregg C; Harper, Ronald M; Woo, Mary A

2013-02-01

Heart failure (HF) patients exhibit depression and executive function impairments that contribute to HF mortality. Using specialized magnetic resonance imaging (MRI) analysis procedures, brain changes appear in areas regulating these functions (mammillary bodies, hippocampi, and frontal cortex). However, specialized MRI procedures are not part of standard clinical assessment for HF (which is usually a visual evaluation), and it is unclear whether visual MRI examination can detect changes in these structures. Using brain MRI, we visually examined the mammillary bodies and frontal cortex for global and hippocampi for global and regional tissue changes in 17 HF and 50 control subjects. Significantly global changes emerged in the right mammillary body (HF 1.18 ± 1.13 vs control 0.52 ± 0.74; P = .024), right hippocampus (HF 1.53 ± 0.94 vs control 0.80 ± 0.86; P = .005), and left frontal cortex (HF 1.76 ± 1.03 vs control 1.24 ± 0.77; P = .034). Comparison of the visual method with specialized MRI techniques corroborates right hippocampal and left frontal cortical, but not mammillary body, tissue changes. Visual examination of brain MRI can detect damage in HF in areas regulating depression and executive function, including the right hippocampus and left frontal cortex. Visual MRI assessment in HF may facilitate evaluation of injury to these structures and the assessment of the impact of potential treatments for this damage. Copyright © 2013 Elsevier Inc. All rights reserved.

View-Independent Working Memory Representations of Artificial Shapes in Prefrontal and Posterior Regions of the Human Brain.

PubMed

Christophel, Thomas B; Allefeld, Carsten; Endisch, Christian; Haynes, John-Dylan

2018-06-01

Traditional views of visual working memory postulate that memorized contents are stored in dorsolateral prefrontal cortex using an adaptive and flexible code. In contrast, recent studies proposed that contents are maintained by posterior brain areas using codes akin to perceptual representations. An important question is whether this reflects a difference in the level of abstraction between posterior and prefrontal representations. Here, we investigated whether neural representations of visual working memory contents are view-independent, as indicated by rotation-invariance. Using functional magnetic resonance imaging and multivariate pattern analyses, we show that when subjects memorize complex shapes, both posterior and frontal brain regions maintain the memorized contents using a rotation-invariant code. Importantly, we found the representations in frontal cortex to be localized to the frontal eye fields rather than dorsolateral prefrontal cortices. Thus, our results give evidence for the view-independent storage of complex shapes in distributed representations across posterior and frontal brain regions.

Regional metabolism of Met-enkephalin and cholecystokinin on intact ratbrain slices: characterization of specific peptidases.

PubMed

Konkoy, C S; Davis, T P

1995-12-01

The metabolism of Met-enkephalin and cholecystokinin (CCK) 8-(sulfated) by intact microslices was studied in rat brain regions. Incubation of brain slices with Met-enkephalin (400 microM) resulted in a linear rate of disappearance of parent peptide and appearance of metabolic fragments whose rate of accumulation was specific to brain region. The degradative rate (pmol/min/mg of protein) of Met-enkephalin was high in caudate-putamen (5,160 +/- 120) and lower in nucleus accumbens (3,630 +/- 110) and frontal cortex (3,180 +/- 120). Inhibition of aminopeptidases decreased Met-enkephalin degradation (50-97% vs. control) in frontal cortex but was less effective in caudate-putamen (20-34%). Tyr-Gly-Gly and Phe-Met were recovered in caudate-putamen and nucleus accumbens, whereas negligible quantities of these fragments were recovered from frontal cortex. Phosphoramidon, an inhibitor of neutral endopeptidase 24.11, decreased Met-enkephalin degradation in caudate-putamen (14%) but had no effect on that in frontal cortex. A cocktail of bestatin or leuhistin (inhibitors of aminopeptidases), phosphoramidon, and captopril (an inhibitor of angiotensin converting enzyme) protected Met-enkephalin from degradation (recovery > 95%) in caudate-putamen. CCK 8-(sulfated) degradation on slices from caudate-putamen, nucleus accumbens, and frontal cortex was not altered by inhibitors of neutral endopeptidase 24.11, metalloendopeptidase 24.15, angiotensin converting enzyme, or thiol proteases. Inhibitors of either aminopeptidases or serine proteases produced small reductions (13-30%) in CCK degradation in each region. These data provide evidence for regional and structural specificity in terminating the actions of neuropeptides.

Progesterone receptor isoforms expression pattern in the rat brain during the estrous cycle.

PubMed

Guerra-Araiza, C; Cerbón, M A; Morimoto, S; Camacho-Arroyo, I

2000-03-24

Progesterone receptor (PR) isoforms expression was determined in the hypothalamus, the preoptic area, the hippocampus and the frontal cerebral cortex of the rat at 12:00 h on each day of the estrous cycle by using reverse transcription coupled to polymerase chain reaction. Rats under a 14:10 h light-dark cycle, with lights on at 06:00 h were used. We found that PR-B isoform was predominant in the hypothalamus, the preoptic area and the frontal cerebral cortex. Both PR isoforms were similarly expressed in the hippocampus. The highest PR-B expression was found on proestrus day in the hypothalamus; on metestrus in the preoptic area; and on diestrus in the frontal cortex. We observed no changes in PR isoforms expression in the hippocampus during the estrous cycle. These results indicate that PR isoforms expression is differentially regulated during the estrous cycle in distinct brain regions and that PR-B may be involved in progesterone actions upon the hypothalamus, the preoptic area and the frontal cortex of the rat.

Orbito-frontal cortex and thalamus volumes in the patients with obsessive-compulsive disorder before and after cognitive behavioral therapy.

PubMed

Atmaca, Murad; Yildirim, Hanefi; Yilmaz, Seda; Caglar, Neslihan; Mermi, Osman; Korkmaz, Sevda; Akaslan, Unsal; Gurok, M Gurkan; Kekilli, Yasemin; Turkcapar, Hakan

2018-07-01

Background The effect of a variety of treatment modalities including psychopharmacological and cognitive behavioral therapy on the brain volumes and neurochemicals have not been investigated enough in the patients with obsessive-compulsive disorder. Therefore, in the present study, we aimed to investigate the effect of cognitive behavioral therapy on the volumes of the orbito-frontal cortex and thalamus regions which seem to be abnormal in the patients with obsessive-compulsive disorder. We hypothesized that there would be change in the volumes of the orbito-frontal cortex and thalamus. Methods Twelve patients with obsessive-compulsive disorder and same number of healthy controls were included into the study. At the beginning of the study, the volumes of the orbito-frontal cortex and thalamus were compared by using magnetic resonance imaging. In addition, volumes of these regions were measured before and after the cognitive behavioral therapy treatment in the patient group. Results The patients with obsessive-compulsive disorder had greater left and right thalamus volumes and smaller left and right orbito-frontal cortex volumes compared to those of healthy control subjects at the beginning of the study. When we compared baseline volumes of the patients with posttreatment ones, we detected that thalamus volumes significantly decreased throughout the period for both sides and that the orbito-frontal cortex volumes significantly increased throughout the period for only left side. Conclusions In summary, we found that cognitive behavioral therapy might volumetrically affect the key brain regions involved in the neuroanatomy of obsessive-compulsive disorder. However, future studies with larger sample are required.

The Effects of Taekwondo Training on Brain Connectivity and Body Intelligence.

PubMed

Kim, Young Jae; Cha, Eun Joo; Kim, Sun Mi; Kang, Kyung Doo; Han, Doug Hyun

2015-07-01

Many studies have reported that Taekwondo training could improve body perception, control and brain activity, as assessed with an electroencephalogram. This study aimed to assess body intelligence and brain connectivity in children with Taekwondo training as compared to children without Taekwondo training. Fifteen children with Taekwondo training (TKD) and 13 age- and sex-matched children who had no previous experience of Taekwondo training (controls) were recruited. Body intelligence, clinical characteristics and brain connectivity in all children were assessed with the Body Intelligence Scale (BIS), self-report, and resting state functional magnetic resonance imaging. The mean BIS score in the TKD group was higher than that in the control group. The TKD group showed increased low-frequency fluctuations in the right frontal precentral gyrus and the right parietal precuneus, compared to the control group. The TKD group showed positive cerebellum vermis (lobe VII) seed to the right frontal, left frontal, and left parietal lobe. The control group showed positive cerebellum seed to the left frontal, parietal, and occipital cortex. Relative to the control group, the TKD group showed increased functional connectivity from cerebellum seed to the right inferior frontal gyrus. To the best of our knowledge, this is the first study to assess the effect of Taekwondo training on brain connectivity in children. Taekwondo training improved body intelligence and brain connectivity from the cerebellum to the parietal and frontal cortex.

Decreased GRK3 but not GRK2 expression in frontal cortex from bipolar disorder patients

PubMed Central

Rao, Jagadeesh S; Rapoport, Stanley I; Kim, Hyung-Wook

2009-01-01

Overactivation of G-protein mediated functions and altered G-protein regulation have been reported in bipolar disorder (BD) brain. Further, drugs effective in treating BD are reported to upregulate expression of G-protein receptor kinase (GRK) 3 in rat frontal cortex. We therefore hypothesized that some G-protein subunits and GRK levels would be reduced in the brains of BD patients. We determined protein and mRNA levels of G-protein β and γ subunits, GRK2, and GRK3 in postmortem frontal cortex from 10 BD patients and 10 age-matched controls by using immunoblots and real-time RT-PCR. There were the statistically significant decreases in protein and mRNA levels of G-protein subunits β and γ and of GRK3 in the BD brains but not a significant difference in the GRK2 level. Decreased expression of G-protein subunits and of GRK3 may alter neurotransmission, leading to disturbed cognition and behavior in BD. PMID:19400979

Downregulation of GABA[Subscript A] Receptor Protein Subunits a6, ß2, d, e, ?2, ?, and ?2 in Superior Frontal Cortex of Subjects with Autism

ERIC Educational Resources Information Center

Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Rustan, Oyvind G.; Rooney, Robert J.; Thuras, Paul D.

2014-01-01

We measured protein and mRNA levels for nine gamma-aminobutyric acid A (GABA[subscript A]) receptor subunits in three brain regions (cerebellum, superior frontal cortex, and parietal cortex) in subjects with autism versus matched controls. We observed changes in mRNA for a number of GABA[subscript A] and GABA[subscript B] subunits and overall…

The Organization of Dorsal Frontal Cortex in Humans and Macaques

PubMed Central

Mars, Rogier B.; Noonan, MaryAnn P.; Neubert, Franz-Xaver; Jbabdi, Saad; O'Reilly, Jill X.; Filippini, Nicola; Thomas, Adam G.; Rushworth, Matthew F.

2013-01-01

The human dorsal frontal cortex has been associated with the most sophisticated aspects of cognition, including those that are thought to be especially refined in humans. Here we used diffusion-weighted magnetic resonance imaging (DW-MRI) and functional MRI (fMRI) in humans and macaques to infer and compare the organization of dorsal frontal cortex in the two species. Using DW-MRI tractography-based parcellation, we identified 10 dorsal frontal regions lying between the human inferior frontal sulcus and cingulate cortex. Patterns of functional coupling between each area and the rest of the brain were then estimated with fMRI and compared with functional coupling patterns in macaques. Areas in human medial frontal cortex, including areas associated with high-level social cognitive processes such as theory of mind, showed a surprising degree of similarity in their functional coupling patterns with the frontal pole, medial prefrontal, and dorsal prefrontal convexity in the macaque. We failed to find evidence for “new” regions in human medial frontal cortex. On the lateral surface, comparison of functional coupling patterns suggested correspondences in anatomical organization distinct from those that are widely assumed. A human region sometimes referred to as lateral frontal pole more closely resembled area 46, rather than the frontal pole, of the macaque. Overall the pattern of results suggest important similarities in frontal cortex organization in humans and other primates, even in the case of regions thought to carry out uniquely human functions. The patterns of interspecies correspondences are not, however, always those that are widely assumed. PMID:23884933

Greater Activity in the Frontal Cortex on Left Curves: A Vector-Based fNIRS Study of Left and Right Curve Driving

PubMed Central

Oka, Noriyuki; Yoshino, Kayoko; Yamamoto, Kouji; Takahashi, Hideki; Li, Shuguang; Sugimachi, Toshiyuki; Nakano, Kimihiko; Suda, Yoshihiro; Kato, Toshinori

2015-01-01

Objectives In the brain, the mechanisms of attention to the left and the right are known to be different. It is possible that brain activity when driving also differs with different horizontal road alignments (left or right curves), but little is known about this. We found driver brain activity to be different when driving on left and right curves, in an experiment using a large-scale driving simulator and functional near-infrared spectroscopy (fNIRS). Research Design and Methods The participants were fifteen healthy adults. We created a course simulating an expressway, comprising straight line driving and gentle left and right curves, and monitored the participants under driving conditions, in which they drove at a constant speed of 100 km/h, and under non-driving conditions, in which they simply watched the screen (visual task). Changes in hemoglobin concentrations were monitored at 48 channels including the prefrontal cortex, the premotor cortex, the primary motor cortex and the parietal cortex. From orthogonal vectors of changes in deoxyhemoglobin and changes in oxyhemoglobin, we calculated changes in cerebral oxygen exchange, reflecting neural activity, and statistically compared the resulting values from the right and left curve sections. Results Under driving conditions, there were no sites where cerebral oxygen exchange increased significantly more during right curves than during left curves (p > 0.05), but cerebral oxygen exchange increased significantly more during left curves (p < 0.05) in the right premotor cortex, the right frontal eye field and the bilateral prefrontal cortex. Under non-driving conditions, increases were significantly greater during left curves (p < 0.05) only in the right frontal eye field. Conclusions Left curve driving was thus found to require more brain activity at multiple sites, suggesting that left curve driving may require more visual attention than right curve driving. The right frontal eye field was activated under both driving and non-driving conditions. PMID:25993263

Greater Activity in the Frontal Cortex on Left Curves: A Vector-Based fNIRS Study of Left and Right Curve Driving.

PubMed

Oka, Noriyuki; Yoshino, Kayoko; Yamamoto, Kouji; Takahashi, Hideki; Li, Shuguang; Sugimachi, Toshiyuki; Nakano, Kimihiko; Suda, Yoshihiro; Kato, Toshinori

2015-01-01

In the brain, the mechanisms of attention to the left and the right are known to be different. It is possible that brain activity when driving also differs with different horizontal road alignments (left or right curves), but little is known about this. We found driver brain activity to be different when driving on left and right curves, in an experiment using a large-scale driving simulator and functional near-infrared spectroscopy (fNIRS). The participants were fifteen healthy adults. We created a course simulating an expressway, comprising straight line driving and gentle left and right curves, and monitored the participants under driving conditions, in which they drove at a constant speed of 100 km/h, and under non-driving conditions, in which they simply watched the screen (visual task). Changes in hemoglobin concentrations were monitored at 48 channels including the prefrontal cortex, the premotor cortex, the primary motor cortex and the parietal cortex. From orthogonal vectors of changes in deoxyhemoglobin and changes in oxyhemoglobin, we calculated changes in cerebral oxygen exchange, reflecting neural activity, and statistically compared the resulting values from the right and left curve sections. Under driving conditions, there were no sites where cerebral oxygen exchange increased significantly more during right curves than during left curves (p > 0.05), but cerebral oxygen exchange increased significantly more during left curves (p < 0.05) in the right premotor cortex, the right frontal eye field and the bilateral prefrontal cortex. Under non-driving conditions, increases were significantly greater during left curves (p < 0.05) only in the right frontal eye field. Left curve driving was thus found to require more brain activity at multiple sites, suggesting that left curve driving may require more visual attention than right curve driving. The right frontal eye field was activated under both driving and non-driving conditions.

Age-related changes in brain activation associated with dimensional shifts of attention: an fMRI study.

PubMed

Morton, J Bruce; Bosma, Rachael; Ansari, Daniel

2009-05-15

Brain activation associated with dimensional shifts of attention was measured in 14 children and 13 adults using 4 T fMRI. Across all participants, dimensional shifting was associated with activity in a distributed frontoparietal network, including superior parietal cortex, dorsolateral prefrontal cortex, inferior frontal junction, and the pre-supplementary motor region. There were also age-related differences in brain activity, with children but not adults showing an effect of dimension shifting in the right superior frontal sulcus, and adults but not children showing an effect of dimension shifting in the left superior parietal cortex and the right thalamus. These differences were likely not attributable to behavioral differences as children and adults performed comparably. Implications for neurodevelopmental accounts of shifting are discussed.

Co-localisation of abnormal brain structure and function in specific language impairment.

PubMed

Badcock, Nicholas A; Bishop, Dorothy V M; Hardiman, Mervyn J; Barry, Johanna G; Watkins, Kate E

2012-03-01

We assessed the relationship between brain structure and function in 10 individuals with specific language impairment (SLI), compared to six unaffected siblings, and 16 unrelated control participants with typical language. Voxel-based morphometry indicated that grey matter in the SLI group, relative to controls, was increased in the left inferior frontal cortex and decreased in the right caudate nucleus and superior temporal cortex bilaterally. The unaffected siblings also showed reduced grey matter in the caudate nucleus relative to controls. In an auditory covert naming task, the SLI group showed reduced activation in the left inferior frontal cortex, right putamen, and in the superior temporal cortex bilaterally. Despite spatially coincident structural and functional abnormalities in frontal and temporal areas, the relationships between structure and function in these regions were different. These findings suggest multiple structural and functional abnormalities in SLI that are differently associated with receptive and expressive language processing. Copyright © 2011 Elsevier Inc. All rights reserved.

Expression of Tau Pathology-Related Proteins in Different Brain Regions: A Molecular Basis of Tau Pathogenesis.

PubMed

Hu, Wen; Wu, Feng; Zhang, Yanchong; Gong, Cheng-Xin; Iqbal, Khalid; Liu, Fei

2017-01-01

Microtubule-associated protein tau is hyperphosphorylated and aggregated in affected neurons in Alzheimer disease (AD) brains. The tau pathology starts from the entorhinal cortex (EC), spreads to the hippocampus and frontal and temporal cortices, and finally to all isocortex areas, but the cerebellum is spared from tau lesions. The molecular basis of differential vulnerability of different brain regions to tau pathology is not understood. In the present study, we analyzed brain regional expressions of tau and tau pathology-related proteins. We found that tau was hyperphosphorylated at multiple sites in the frontal cortex (FC), but not in the cerebellum, from AD brain. The level of tau expression in the cerebellum was about 1/4 of that seen in the frontal and temporal cortices in human brain. In the rat brain, the expression level of tau with three microtubule-binding repeats (3R-tau) was comparable in the hippocampus, EC, FC, parietal-temporal cortex (PTC), occipital-temporal cortex (OTC), striatum, thalamus, olfactory bulb (OB) and cerebellum. However, the expression level of 4R-tau was the highest in the EC and the lowest in the cerebellum. Tau phosphatases, kinases, microtubule-related proteins and other tau pathology-related proteins were also expressed in a region-specific manner in the rat brain. These results suggest that higher levels of tau and tau kinases in the EC and low levels of these proteins in the cerebellum may accounts for the vulnerability and resistance of these representative brain regions to the development of tau pathology, respectively. The present study provides the regional expression profiles of tau and tau pathology-related proteins in the brain, which may help understand the brain regional vulnerability to tau pathology in neurodegenerative tauopathies.

Laterality patterns of brain functional connectivity: gender effects.

PubMed

Tomasi, Dardo; Volkow, Nora D

2012-06-01

Lateralization of brain connectivity may be essential for normal brain function and may be sexually dimorphic. Here, we study the laterality patterns of short-range (implicated in functional specialization) and long-range (implicated in functional integration) connectivity and the gender effects on these laterality patterns. Parallel computing was used to quantify short- and long-range functional connectivity densities in 913 healthy subjects. Short-range connectivity was rightward lateralized and most asymmetrical in areas around the lateral sulcus, whereas long-range connectivity was rightward lateralized in lateral sulcus and leftward lateralizated in inferior prefrontal cortex and angular gyrus. The posterior inferior occipital cortex was leftward lateralized (short- and long-range connectivity). Males had greater rightward lateralization of brain connectivity in superior temporal (short- and long-range), inferior frontal, and inferior occipital cortices (short-range), whereas females had greater leftward lateralization of long-range connectivity in the inferior frontal cortex. The greater lateralization of the male's brain (rightward and predominantly short-range) may underlie their greater vulnerability to disorders with disrupted brain asymmetries (schizophrenia, autism).

Laterality Patterns of Brain Functional Connectivity: Gender Effects

PubMed Central

Tomasi, Dardo; Volkow, Nora D.

2012-01-01

Lateralization of brain connectivity may be essential for normal brain function and may be sexually dimorphic. Here, we study the laterality patterns of short-range (implicated in functional specialization) and long-range (implicated in functional integration) connectivity and the gender effects on these laterality patterns. Parallel computing was used to quantify short- and long-range functional connectivity densities in 913 healthy subjects. Short-range connectivity was rightward lateralized and most asymmetrical in areas around the lateral sulcus, whereas long-range connectivity was rightward lateralized in lateral sulcus and leftward lateralizated in inferior prefrontal cortex and angular gyrus. The posterior inferior occipital cortex was leftward lateralized (short- and long-range connectivity). Males had greater rightward lateralization of brain connectivity in superior temporal (short- and long-range), inferior frontal, and inferior occipital cortices (short-range), whereas females had greater leftward lateralization of long-range connectivity in the inferior frontal cortex. The greater lateralization of the male's brain (rightward and predominantly short-range) may underlie their greater vulnerability to disorders with disrupted brain asymmetries (schizophrenia, autism). PMID:21878483

Effects of Crocin on Learning and Memory in Rats Under Chronic Restraint Stress with Special Focus on the Hippocampal and Frontal Cortex Corticosterone Levels

PubMed Central

Dastgerdi, Azadehalsadat Hosseini; Radahmadi, Maryam; Pourshanazari, Ali Asghar; Dastgerdi, Hajaralsadat Hosseini

2017-01-01

Background: Chronic stress adversely influences brain functions while crocin, as an effective component of saffron, exhibits positive effects on memory processes. This study investigated the effects of different doses of crocin on the improvement of learning and memory as well as corticosterone (CORT) levels in the hippocampus and frontal cortex of rats subjected to chronic stress. Materials and Methods: Forty male rats were randomly allocated to five different groups (n = 8): Control, sham; stress (6 h/day for 21 days) groups, and two groups receiving daily intraperitoneal injections of one of two doses (30 and 60 mg/kg) of crocin accompanied by 21 days of restraint stress. Latency was evaluated as a brain function using the passive avoidance test before and one-day after a foot shock. CORT levels were measured in the homogenized hippocampus and frontal cortex. Results: Results revealed that chronic stress had a significantly (P < 0.01) negative effect on memory. Crocin (30 and 60 mg/kg), however, gave increase to significantly (P < 0.01 and P < 0.05; respectively) improved memory functions in the stressed rats. Furthermore, the CORT levels in the hippocampus and frontal cortex declined significantly (P < 0.05) in the stress group compared to the control. Only a crocin dose of 30 mg/kg was observed modulate significantly (P < 0.05) the CORT levels in the hippocampus and frontal cortex in the stressed group. Conclusions: It was found that the lower crocin dose (30 mg/kg) had more beneficial effects than its higher (60 mg/kg) dose on learning and memory under chronic stress conditions. Moreover, it was speculated that different doses of crocin act on different neurotransmitters and biochemical factors in the brain. PMID:29387668

Effect of neonatal nociceptin or nocistatin imprinting on the brain concentration of biogenic amines and their metabolites.

PubMed

Tekes, Kornélia; Gyenge, Melinda; Sótonyi, Péter; Csaba, György

2009-04-01

Noradrenaline (NA), dopamine (DA), homovanillic acid (HA), serotonin (5HT) and 5-hydroxyindole acetic acid (5HIAA) content of five brain regions (hypothalamus, hippocampus, brainstem, striatum and frontal cortex) and the cerebrospinal fluid (CSF) was measured in adult (three months old) male and female rats treated neonatally with a single dose of 10 microg nociceptin (NC) or 10 microg nocistatin (NS) for hormonal imprinting. The biogenic amine and metabolite content of cerebrospinal fluid was also determined. In NC treated animals the serotonergic, dopaminergic as well as noradrenergic systems were influenced by the imprinting. The 5HT level increased in hypothalamus, the 5HIAA tissue levels were found increased in hypothalamus. Hippocampus and striatum and the HVA levels increased highly significantly in brainstem. Dopamine level decreased significantly in striatum, however in frontal cortex both noradrenalin and 5HIAA level decreased. Nevertheless, in NS-treated rats decreased NA tissue levels were found in hypothalamus, brainstem and frontal cortex. Decreased DA levels were found in the hypothalamus, brainstem and striatum. NS imprinting resulted in decreased HVA level, but increased one in the brainstem. The 5HT levels decreased in the hypothalamus, brainstem, striatum and frontal cortex, while 5HIAA content of CSF, and frontal cortex decreased, and that of hypothalamus, hippocampus and striatum increased. There was no significant difference between genders except in the 5HT tissue levels of NC treated rats. Data presented show that neonatal imprinting both by NC and NS have long-lasting and brain area specific effects. In earlier experiments endorphin imprinting also influenced the serotonergic system suggesting that during labour release of pain-related substances may durably affect the serotonergic (dopaminergic, adrenergic) system which can impress the animals' later behavior.

Simultaneous quantification of monoamine neurotransmitters and their biogenic metabolites intracellularly and extracellularly in primary neuronal cell cultures and in sub-regions of guinea pig brain.

PubMed

Schou-Pedersen, Anne Marie V; Hansen, Stine N; Tveden-Nyborg, Pernille; Lykkesfeldt, Jens

2016-08-15

In the present paper, we describe a validated chromatographic method for the simultaneous quantification of monoamine neurotransmitters and their biogenic metabolites intracellularly and extracellularly in primary neuronal cell culture and in sub-regions of the guinea pig brain. Electrochemical detection provided limits of quantifications (LOQs) between 3.6 and 12nM. Within the linear range, obtained recoveries were from 90.9±9.9 to 120±14% and intra-day and inter-day precisions found to be less than 5.5% and 12%, respectively. The analytical method was applicable for quantification of intracellular and extracellular amounts of monoamine neurotransmitters and their metabolites in guinea pig frontal cortex and hippocampal primary neuronal cell cultures. Noradrenaline, dopamine and serotonin were found to be in a range from 0.31 to 1.7pmol per 2 million cells intracellularly, but only the biogenic metabolites could be detected extracellularly. Distinct differences in monoamine concentrations were observed when comparing concentrations in guinea pig frontal cortex and cerebellum tissue with higher amounts of dopamine and its metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid in frontal cortex, as compared to cerebellum. The chemical turnover in frontal cortex tissue of guinea pig was for serotonin successfully predicted from the turnover observed in the frontal cortex cell culture. In conclusion, the present analytical method shows high precision, accuracy and sensitivity and is broadly applicable to monoamine measurements in cell cultures as well as brain biopsies from animal models used in preclinical neurochemistry. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Crocin on Learning and Memory in Rats Under Chronic Restraint Stress with Special Focus on the Hippocampal and Frontal Cortex Corticosterone Levels.

PubMed

Dastgerdi, Azadehalsadat Hosseini; Radahmadi, Maryam; Pourshanazari, Ali Asghar; Dastgerdi, Hajaralsadat Hosseini

2017-01-01

Chronic stress adversely influences brain functions while crocin, as an effective component of saffron, exhibits positive effects on memory processes. This study investigated the effects of different doses of crocin on the improvement of learning and memory as well as corticosterone (CORT) levels in the hippocampus and frontal cortex of rats subjected to chronic stress. Forty male rats were randomly allocated to five different groups ( n = 8): Control, sham; stress (6 h/day for 21 days) groups, and two groups receiving daily intraperitoneal injections of one of two doses (30 and 60 mg/kg) of crocin accompanied by 21 days of restraint stress. Latency was evaluated as a brain function using the passive avoidance test before and one-day after a foot shock. CORT levels were measured in the homogenized hippocampus and frontal cortex. Results revealed that chronic stress had a significantly ( P < 0.01) negative effect on memory. Crocin (30 and 60 mg/kg), however, gave increase to significantly ( P < 0.01 and P < 0.05; respectively) improved memory functions in the stressed rats. Furthermore, the CORT levels in the hippocampus and frontal cortex declined significantly ( P < 0.05) in the stress group compared to the control. Only a crocin dose of 30 mg/kg was observed modulate significantly ( P < 0.05) the CORT levels in the hippocampus and frontal cortex in the stressed group. It was found that the lower crocin dose (30 mg/kg) had more beneficial effects than its higher (60 mg/kg) dose on learning and memory under chronic stress conditions. Moreover, it was speculated that different doses of crocin act on different neurotransmitters and biochemical factors in the brain.

Modulating phonemic fluency performance in healthy subjects with transcranial magnetic stimulation over the left or right lateral frontal cortex.

PubMed

Smirni, Daniela; Turriziani, Patrizia; Mangano, Giuseppa Renata; Bracco, Martina; Oliveri, Massimiliano; Cipolotti, Lisa

2017-07-28

A growing body of evidence have suggested that non-invasive brain stimulation techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), can improve the performance of aphasic patients in language tasks. For example, application of inhibitory rTMS or tDCs over the right frontal lobe of dysphasic patients resulted in improved naming abilities. Several studies have also reported that in healthy controls (HC) tDCS application over the left prefrontal cortex (PFC) improve performance in naming and semantic fluency tasks. The aim of this study was to investigate in HC, for the first time, the effects of inhibitory repetitive TMS (rTMS) over left and right lateral frontal cortex (BA 47) on two phonemic fluency tasks (FAS or FPL). 44 right-handed HCs were administered rTMS or sham over the left or right lateral frontal cortex in two separate testing sessions, with a 24h interval, followed by the two phonemic fluency tasks. To account for possible practice effects, an additional 22 HCs were tested on only the phonemic fluency task across two sessions with no stimulation. We found that rTMS-inhibition over the left lateral frontal cortex significantly worsened phonemic fluency performance when compared to sham. In contrast, rTMS-inhibition over the right lateral frontal cortex significantly improved phonemic fluency performance when compared to sham. These results were not accounted for practice effects. We speculated that rTMS over the right lateral frontal cortex may induce plastic neural changes to the left lateral frontal cortex by suppressing interhemispheric inhibitory interactions. This resulted in an increased excitability (disinhibition) of the contralateral unstimulated left lateral frontal cortex, consequently enhancing phonemic fluency performance. Conversely, application of rTMS over the left lateral frontal cortex may induce a temporary, virtual lesion, with effects similar to those reported in left frontal patients. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multi-frequency localization of aberrant brain activity in autism spectrum disorder.

PubMed

Xiang, Jing; Korostenskaja, Milena; Molloy, Cynthia; deGrauw, Xinyao; Leiken, Kimberly; Gilman, Carley; Meinzen-Derr, Jareen; Fujiwara, Hisako; Rose, Douglas F; Mitchell, Terry; Murray, Donna S

2016-01-01

The abnormality of intrinsic brain activity in autism spectrum disorders (ASDs) is still inconclusive. Contradictory results have been found pointing towards hyper-activity or hypo-activity in various brain regions. The present research aims to investigate the spatial and spectral signatures of aberrant brain activity in an unprecedented frequency range of 1-2884 Hz at source levels in ASD using newly developed methods. Seven ASD subjects and age- and gender-matched controls were studied using a high-sampling rate magnetoencephalography (MEG) system. Brain activity in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), low gamma (30-55 Hz), high gamma (65-90 Hz), ripples (90-200 Hz), high-frequency oscillations (HFOs, 200-1000 Hz), and very high-frequency oscillations (VHFOs, 1000-2884 Hz) was volumetrically localized and measured using wavelet and beamforming. In comparison to controls, ASD subjects had significantly higher odds of alpha activity (8-12 Hz) in the sensorimotor cortex (mu rhythm), and generally high-frequency activity (90-2884 Hz) in the frontal cortex. The source power of HFOs (200-1000 Hz) in the frontal cortex in ASD was significantly elevated as compared with controls. The results suggest that ASD has significantly altered intrinsic brain activity in both low- and high-frequency ranges. Increased intrinsic high-frequency activity in the frontal cortex may play a key role in ASD. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

Hemodynamic changes in the breast and frontal cortex of mothers during breastfeeding.

PubMed

Tanimoto, Kimie; Kusaka, Takashi; Nishida, Tomoko; Ogawa, Kayo; Kato, Ikuko; Ijichi, Sonoko; Mikami, Junko; Sobue, Ikuko; Isobe, Kenichi; Itoh, Susumu

2011-10-01

The objective of this study was to confirm physiological reactions in the breast and brain in mothers during breastfeeding and collect basic objective data, aiming at effective support for breastfeeding. Ten healthy women who were exclusively breastfeeding their babies participated in this study. Changes in the concentration of oxygenated Hb (oxyHb) and deoxygenated Hb in the breasts and frontal cortex of these women during breastfeeding lactation were measured using double-channel near-infrared spectroscopy (NIRS). Changes were measured in three conditions: (1) in both breasts; (2) the ipsilateral breast and frontal cortex; and (3) the contralateral breast and frontal cortex. OxyHb and total Hb (totalHb) levels in the bilateral breasts decreased significantly after the onset of breastfeeding in comparison with prebreastfeeding levels. These two values repeatedly increased and decreased thereafter. In the frontal cortex, regardless of which breast was involved, oxyHb and totalHb levels increased significantly in comparison with prebreastfeeding levels. Similar hemodynamic changes occurred simultaneously in the bilateral breasts during breastfeeding regardless of the feeding or nonfeeding side. Hemodynamic changes were also noted in the frontal cortex, but the reactions in the breast and prefrontal cortex were different and not synchronous, confirming that the physiological circulatory dynamics during breastfeeding vary among organs.

Emotion Regulation in the Brain: Conceptual Issues and Directions for Developmental Research

ERIC Educational Resources Information Center

Lewis, Marc D.; Stieben, Jim

2004-01-01

Emotion regulation cannot be temporally distinguished from emotion in the brain, but activation patterns in prefrontal cortex appear to mediate cognitive control during emotion episodes. Frontal event-related potentials (ERPs) can tap cognitive control hypothetically mediated by the anterior cingulate cortex, and developmentalists have used these…

Issues in localization of brain function: The case of lateralized frontal cortex in cognition, emotion, and psychopathology.

PubMed

Miller, Gregory A; Crocker, Laura D; Spielberg, Jeffrey M; Infantolino, Zachary P; Heller, Wendy

2013-01-01

The appeal of simple, sweeping portraits of large-scale brain mechanisms relevant to psychological phenomena competes with a rich, complex research base. As a prominent example, two views of frontal brain organization have emphasized dichotomous lateralization as a function of either emotional valence (positive/negative) or approach/avoidance motivation. Compelling findings support each. The literature has struggled to choose between them for three decades, without success. Both views are proving untenable as comprehensive models. Evidence of other frontal lateralizations, involving distinctions among dimensions of depression and anxiety, make a dichotomous view even more problematic. Recent evidence indicates that positive valence and approach motivation are associated with different areas in the left-hemisphere. Findings that appear contradictory at the level of frontal lobes as the units of analysis can be accommodated because hemodynamic and electromagnetic neuroimaging studies suggest considerable functional differentiation, in specialization and activation, of subregions of frontal cortex, including their connectivity to each other and to other regions. Such findings contribute to a more nuanced understanding of functional localization that accommodates aspects of multiple theoretical perspectives.

Issues in localization of brain function: The case of lateralized frontal cortex in cognition, emotion, and psychopathology

PubMed Central

Miller, Gregory A.; Crocker, Laura D.; Spielberg, Jeffrey M.; Infantolino, Zachary P.; Heller, Wendy

2013-01-01

The appeal of simple, sweeping portraits of large-scale brain mechanisms relevant to psychological phenomena competes with a rich, complex research base. As a prominent example, two views of frontal brain organization have emphasized dichotomous lateralization as a function of either emotional valence (positive/negative) or approach/avoidance motivation. Compelling findings support each. The literature has struggled to choose between them for three decades, without success. Both views are proving untenable as comprehensive models. Evidence of other frontal lateralizations, involving distinctions among dimensions of depression and anxiety, make a dichotomous view even more problematic. Recent evidence indicates that positive valence and approach motivation are associated with different areas in the left-hemisphere. Findings that appear contradictory at the level of frontal lobes as the units of analysis can be accommodated because hemodynamic and electromagnetic neuroimaging studies suggest considerable functional differentiation, in specialization and activation, of subregions of frontal cortex, including their connectivity to each other and to other regions. Such findings contribute to a more nuanced understanding of functional localization that accommodates aspects of multiple theoretical perspectives. PMID:23386814

Neural Tuning to Low-Level Features of Speech throughout the Perisylvian Cortex.

PubMed

Berezutskaya, Julia; Freudenburg, Zachary V; Güçlü, Umut; van Gerven, Marcel A J; Ramsey, Nick F

2017-08-16

Despite a large body of research, we continue to lack a detailed account of how auditory processing of continuous speech unfolds in the human brain. Previous research showed the propagation of low-level acoustic features of speech from posterior superior temporal gyrus toward anterior superior temporal gyrus in the human brain (Hullett et al., 2016). In this study, we investigate what happens to these neural representations past the superior temporal gyrus and how they engage higher-level language processing areas such as inferior frontal gyrus. We used low-level sound features to model neural responses to speech outside of the primary auditory cortex. Two complementary imaging techniques were used with human participants (both males and females): electrocorticography (ECoG) and fMRI. Both imaging techniques showed tuning of the perisylvian cortex to low-level speech features. With ECoG, we found evidence of propagation of the temporal features of speech sounds along the ventral pathway of language processing in the brain toward inferior frontal gyrus. Increasingly coarse temporal features of speech spreading from posterior superior temporal cortex toward inferior frontal gyrus were associated with linguistic features such as voice onset time, duration of the formant transitions, and phoneme, syllable, and word boundaries. The present findings provide the groundwork for a comprehensive bottom-up account of speech comprehension in the human brain. SIGNIFICANCE STATEMENT We know that, during natural speech comprehension, a broad network of perisylvian cortical regions is involved in sound and language processing. Here, we investigated the tuning to low-level sound features within these regions using neural responses to a short feature film. We also looked at whether the tuning organization along these brain regions showed any parallel to the hierarchy of language structures in continuous speech. Our results show that low-level speech features propagate throughout the perisylvian cortex and potentially contribute to the emergence of "coarse" speech representations in inferior frontal gyrus typically associated with high-level language processing. These findings add to the previous work on auditory processing and underline a distinctive role of inferior frontal gyrus in natural speech comprehension. Copyright © 2017 the authors 0270-6474/17/377906-15$15.00/0.

Prefrontal connections express individual differences in intrinsic resistance to trading off honesty values against economic benefits

PubMed Central

Dogan, Azade; Morishima, Yosuke; Heise, Felix; Tanner, Carmen; Gibson, Rajna; Wagner, Alexander F.; Tobler, Philippe N.

2016-01-01

Individuals differ profoundly when they decide whether to tell the truth or to be dishonest, particularly in situations where moral motives clash with economic motives, i.e., when truthfulness comes at a monetary cost. These differences should be expressed in the decision network, particularly in prefrontal cortex. However, the interactions between the core players of the decision network during honesty-related decisions involving trade-offs with economic costs remain poorly understood. To investigate brain connectivity patterns associated with individual differences in responding to economic costs of truthfulness, we used functional magnetic resonance imaging and measured brain activations, while participants made decisions concerning honesty. We found that in participants who valued honesty highly, dorsolateral and dorsomedial parts of prefrontal cortex were more tightly coupled with the inferior frontal cortex when economic costs were high compared to when they were low. Finer-grained analysis revealed that information flow from the inferior frontal cortex to the dorsolateral prefrontal cortex and bidirectional information flow between the inferior frontal cortex and dorsomedial prefrontal cortex was associated with a reduced tendency to trade off honesty for economic benefits. Our findings provide a novel account of the neural circuitry that underlies honest decisions in the face of economic temptations. PMID:27646044

Impaired decision-making and selective cortical frontal thinning in Cushing's syndrome.

PubMed

Crespo, Iris; Esther, Granell-Moreno; Santos, Alicia; Valassi, Elena; Yolanda, Vives-Gilabert; De Juan-Delago, Manel; Webb, Susan M; Gómez-Ansón, Beatriz; Resmini, Eugenia

2014-12-01

Cushing's syndrome (CS) is caused by a glucocorticoid excess. This hypercortisolism can damage the prefrontal cortex, known to be important in decision-making. Our aim was to evaluate decision-making in CS and to explore cortical thickness. Thirty-five patients with CS (27 cured, eight medically treated) and thirty-five matched controls were evaluated using Iowa gambling task (IGT) and 3 Tesla magnetic resonance imaging (MRI) to assess cortical thickness. The IGT evaluates decision-making, including strategy and learning during the test. Cortical thickness was determined on MRI using freesurfer software tools, including a whole-brain analysis. There were no differences between medically treated and cured CS patients. They presented an altered decision-making strategy compared to controls, choosing a lower number of the safer cards (P < 0·05). They showed more difficulties than controls to learn the correct profiles of wins and losses for each card group (P < 0·05). In whole-brain analysis, patients with CS showed decreased cortical thickness in the left superior frontal cortex, left precentral cortex, left insular cortex, left and right rostral anterior cingulate cortex, and right caudal middle frontal cortex compared to controls (P < 0·001). Patients with CS failed to learn advantageous strategies and their behaviour was driven by short-term reward and long-term punishment, indicating learning problems because they did not use previous experience as a feedback factor to regulate their choices. These alterations in decision-making and the decreased cortical thickness in frontal areas suggest that chronic hypercortisolism promotes brain changes which are not completely reversible after endocrine remission. © 2014 John Wiley & Sons Ltd.

Effect of antemortem and postmortem factors on ( sup 3 H)MK-801 binding in the human brain: Transient elevation during early childhood

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kornhuber, J.; Mack-Burkhardt, F.; Konradi, C.

1989-01-01

The effect of a number of antemortem and postmortem factors on ({sup 3}H)MK-801 binding was investigated under equilibrium conditions in the frontal cortex of human brains of 38 controls. Binding values transiently increased during the early postnatal period reaching a maximum at the age of about 2 years. After age 10 years ({sup 3}H)MK-801 binding sites disappeared at 5.7% per decade. The storage time of brain tissue had a reducing effect on these binding sites. There was no effect of gender, brain weight or postmortem time interval and the binding sites were bilaterally symmetrically distributed in the frontal cortex.

nNOS expression in the brain of rats after burn and the effect of the ACE inhibitor captopril.

PubMed

Demiralay, Ebru; Saglam, Ibrahim Yaman; Ozdamar, Emine Nur; Sehirli, Ahmet Ozer; Sener, Goksel; Saglam, Esra

2013-08-01

To investigate the role of endogenous neuronal nitric oxide synthase (nNOS) on brain injury after burn and the effects of the captopril. Wistar albino rats (200-250 g) were exposed on the dorsal surface to 90°C (burn) or 25°C (sham) water for 10 s. The ACE group was treated with intraperitoneal 10 mg/kg captopril immediately after burn and this treatment was repeated twice daily. At the end of the 24 h brain samples were taken. nNOS was studied in brain areas by immunohistochemistry. There was no difference between the cerebellar and hypothalamic areas the nNOS expression of all groups. nNOS expression increased in the frontal cortex, striatum and midbrain in the burn group compared to the control group. In the frontal cortex, nNOS expression significantly decreased after ACE inhibitor treatment (p<0.05). The striatal nNOS of the ACE group significantly increased when compared to the control group (p=0.001). In the midbrain of the animals, nNOS decreased in the ACE group. Hippocampal nNOS expression did not change after burn and significantly increased after ACE inhibitor therapy (p<0.05). Our data showed that the pathophysiological events following burn appear to be related to an acute inflammatory reaction which is associated with nNOS in the frontal cortex, striatum and midbrain, and captopril treatment abrogates the nNOS response in the frontal cortex and midbrain. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

Deep brain stimulation of the subthalamic nucleus alters the cortical profile of response inhibition in the beta frequency band: a scalp EEG study in Parkinson's disease

PubMed Central

Swann, Nicole; Poizner, Howard; Houser, Melissa; Gould, Sherrie; Greenhouse, Ian; Cai, Weidong; Strunk, Jon; George, Jobi; Aron, Adam R

2011-01-01

Stopping an initiated response could be implemented by a fronto-basal-ganglia circuit, including the right inferior frontal cortex (rIFC) and the subthalamic nucleus (STN). Intracranial recording studies in humans reveal an increase in beta-band power (~16-20 Hz) within the rIFC and STN when a response is stopped. This suggests that the beta-band could be important for communication in this network. If this is the case, then altering one region should affect the electrophysiological response at the other. We addressed this hypothesis by recording scalp EEG during a stop task while modulating STN activity with deep brain stimulation. We studied 15 human patients with Parkinson's Disease and 15 matched healthy control subjects. Behaviorally, patients OFF stimulation were slower than controls to stop their response. Moreover, stopping speed was improved for ON compared to OFF stimulation. For scalp EEG, there was greater beta power, around the time of stopping, for patients ON compared to OFF stimulation. This effect was stronger over the right compared to left frontal cortex, consistent with the putative right-lateralization of the stopping network. Thus, deep brain stimulation of the STN improved behavioral stopping performance and increased the beta-band response over the right frontal cortex. These results complement other evidence for a structurally-connected, functional, circuit between right frontal cortex and the basal ganglia. The results also suggest that deep brain stimulation of the STN may improve task performance by increasing the fidelity of information transfer within a fronto-basal ganglia circuit. PMID:21490213

Abnormal structural connectivity between the basal ganglia, thalamus, and frontal cortex in patients with disorders of consciousness.

PubMed

Weng, Ling; Xie, Qiuyou; Zhao, Ling; Zhang, Ruibin; Ma, Qing; Wang, Junjing; Jiang, Wenjie; He, Yanbin; Chen, Yan; Li, Changhong; Ni, Xiaoxiao; Xu, Qin; Yu, Ronghao; Huang, Ruiwang

2017-05-01

Consciousness loss in patients with severe brain injuries is associated with reduced functional connectivity of the default mode network (DMN), fronto-parietal network, and thalamo-cortical network. However, it is still unclear if the brain white matter connectivity between the above mentioned networks is changed in patients with disorders of consciousness (DOC). In this study, we collected diffusion tensor imaging (DTI) data from 13 patients and 17 healthy controls, constructed whole-brain white matter (WM) structural networks with probabilistic tractography. Afterward, we estimated and compared topological properties, and revealed an altered structural organization in the patients. We found a disturbance in the normal balance between segregation and integration in brain structural networks and detected significantly decreased nodal centralities primarily in the basal ganglia and thalamus in the patients. A network-based statistical analysis detected a subnetwork with uniformly significantly decreased structural connections between the basal ganglia, thalamus, and frontal cortex in the patients. Further analysis indicated that along the WM fiber tracts linking the basal ganglia, thalamus, and frontal cortex, the fractional anisotropy was decreased and the radial diffusivity was increased in the patients compared to the controls. Finally, using the receiver operating characteristic method, we found that the structural connections within the NBS-derived component that showed differences between the groups demonstrated high sensitivity and specificity (>90%). Our results suggested that major consciousness deficits in DOC patients may be related to the altered WM connections between the basal ganglia, thalamus, and frontal cortex. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lateral Prefrontal Cortex Subregions Make Dissociable Contributions during Fluid Reasoning

PubMed Central

Thompson, Russell; Duncan, John; Owen, Adrian M.

2011-01-01

Reasoning is a key component of adaptable “executive” behavior and is known to depend on a network of frontal and parietal brain regions. However, the mechanisms by which this network supports reasoning and adaptable behavior remain poorly defined. Here, we examine the relationship between reasoning, executive control, and frontoparietal function in a series of nonverbal reasoning experiments. Our results demonstrate that, in accordance with previous studies, a network of frontal and parietal brain regions is recruited during reasoning. Our results also reveal that this network can be fractionated according to how different subregions respond when distinct reasoning demands are manipulated. While increased rule complexity modulates activity within a right lateralized network including the middle frontal gyrus and the superior parietal cortex, analogical reasoning demand—or the requirement to remap rules on to novel features—recruits the left inferior rostrolateral prefrontal cortex and the lateral occipital complex. In contrast, the posterior extent of the inferior frontal gyrus, associated with simpler executive demands, is not differentially sensitive to rule complexity or analogical demand. These findings accord well with the hypothesis that different reasoning demands are supported by different frontal and parietal subregions. PMID:20483908

Increased central immunoreactive beta-endorphin content in patients with Wernicke-Korsakoff syndrome and in alcoholics.

PubMed Central

Summers, J A; Pullan, P T; Kril, J J; Harper, C G

1991-01-01

beta-endorphin, adrenocorticotrophin, and alpha-melanocyte stimulating hormone were measured by radioimmunoassay in three areas of human brain at necropsy in seven subjects with Wernicke-Korsakoff syndrome and in 52 controls. Thiamin concentration in six brain areas was also measured. Mamillary body beta-endorphin concentrations were significantly increased in those with the syndrome compared with controls, and those controls with high alcohol intake showed increased mamillary body beta-endorphin compared with controls with low alcohol intake. Brain thiamin concentration was similar in both groups, with the exception of the brainstem, where it was reduced in subjects with Wernicke-Korsakoff syndrome. Thalamic beta-endorphin in controls was inversely correlated with thiamin in frontal white matter, frontal cortex, parietal white matter and parietal cortex, while beta-endorphin in the hypothalamus of patients was inversely correlated with thiamin in frontal cortex, parietal white matter, thalamus and brainstem. These results suggest that there is a disturbance of the endorphinergic system in Wernicke-Korsakoff syndrome which may be related to alcohol intake. PMID:1650797

Cross-language differences in the brain network subserving intelligible speech.

PubMed

Ge, Jianqiao; Peng, Gang; Lyu, Bingjiang; Wang, Yi; Zhuo, Yan; Niu, Zhendong; Tan, Li Hai; Leff, Alexander P; Gao, Jia-Hong

2015-03-10

How is language processed in the brain by native speakers of different languages? Is there one brain system for all languages or are different languages subserved by different brain systems? The first view emphasizes commonality, whereas the second emphasizes specificity. We investigated the cortical dynamics involved in processing two very diverse languages: a tonal language (Chinese) and a nontonal language (English). We used functional MRI and dynamic causal modeling analysis to compute and compare brain network models exhaustively with all possible connections among nodes of language regions in temporal and frontal cortex and found that the information flow from the posterior to anterior portions of the temporal cortex was commonly shared by Chinese and English speakers during speech comprehension, whereas the inferior frontal gyrus received neural signals from the left posterior portion of the temporal cortex in English speakers and from the bilateral anterior portion of the temporal cortex in Chinese speakers. Our results revealed that, although speech processing is largely carried out in the common left hemisphere classical language areas (Broca's and Wernicke's areas) and anterior temporal cortex, speech comprehension across different language groups depends on how these brain regions interact with each other. Moreover, the right anterior temporal cortex, which is crucial for tone processing, is equally important as its left homolog, the left anterior temporal cortex, in modulating the cortical dynamics in tone language comprehension. The current study pinpoints the importance of the bilateral anterior temporal cortex in language comprehension that is downplayed or even ignored by popular contemporary models of speech comprehension.

Cross-language differences in the brain network subserving intelligible speech

PubMed Central

Ge, Jianqiao; Peng, Gang; Lyu, Bingjiang; Wang, Yi; Zhuo, Yan; Niu, Zhendong; Tan, Li Hai; Leff, Alexander P.; Gao, Jia-Hong

2015-01-01

How is language processed in the brain by native speakers of different languages? Is there one brain system for all languages or are different languages subserved by different brain systems? The first view emphasizes commonality, whereas the second emphasizes specificity. We investigated the cortical dynamics involved in processing two very diverse languages: a tonal language (Chinese) and a nontonal language (English). We used functional MRI and dynamic causal modeling analysis to compute and compare brain network models exhaustively with all possible connections among nodes of language regions in temporal and frontal cortex and found that the information flow from the posterior to anterior portions of the temporal cortex was commonly shared by Chinese and English speakers during speech comprehension, whereas the inferior frontal gyrus received neural signals from the left posterior portion of the temporal cortex in English speakers and from the bilateral anterior portion of the temporal cortex in Chinese speakers. Our results revealed that, although speech processing is largely carried out in the common left hemisphere classical language areas (Broca’s and Wernicke’s areas) and anterior temporal cortex, speech comprehension across different language groups depends on how these brain regions interact with each other. Moreover, the right anterior temporal cortex, which is crucial for tone processing, is equally important as its left homolog, the left anterior temporal cortex, in modulating the cortical dynamics in tone language comprehension. The current study pinpoints the importance of the bilateral anterior temporal cortex in language comprehension that is downplayed or even ignored by popular contemporary models of speech comprehension. PMID:25713366

The threshold for conscious report: Signal loss and response bias in visual and frontal cortex.

PubMed

van Vugt, Bram; Dagnino, Bruno; Vartak, Devavrat; Safaai, Houman; Panzeri, Stefano; Dehaene, Stanislas; Roelfsema, Pieter R

2018-05-04

Why are some visual stimuli consciously detected, whereas others remain subliminal? We investigated the fate of weak visual stimuli in the visual and frontal cortex of awake monkeys trained to report stimulus presence. Reported stimuli were associated with strong sustained activity in the frontal cortex, and frontal activity was weaker and quickly decayed for unreported stimuli. Information about weak stimuli could be lost at successive stages en route from the visual to the frontal cortex, and these propagation failures were confirmed through microstimulation of area V1. Fluctuations in response bias and sensitivity during perception of identical stimuli were traced back to prestimulus brain-state markers. A model in which stimuli become consciously reportable when they elicit a nonlinear ignition process in higher cortical areas explained our results. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Local administration of a cannabinoid agonist alters norepinephrine efflux in the rat frontal cortex.

PubMed

Page, M E; Oropeza, V C; Van Bockstaele, E J

2008-01-24

Delta(9)-tetrahydrocannabinol, the main psychoactive ingredient in marijuana, activates specific cannabinoid (CB) receptors to exert complex actions on modulatory neurotransmitters involved in attention and cognition. Previous research has demonstrated that systemic administration of the synthetic cannabinoid agonist, WIN 55,212-2, increases norepinephrine efflux in the frontal cortex. The distribution of CB1 receptors on noradrenergic fibers in the frontal cortex suggests this may be one potential site for the regulation of norepinephrine release. In the present study, we first examined the ability of a CB1 antagonist, applied locally in the frontal cortex of adult male Sprague-Dawley rats, to block the actions of systemic WIN 55,212-2. Pretreatment with SR 141716A (300 microM) significantly attenuated the excitatory effects of WIN 55,212-2 (15 mg/kg, i.p.). Next, the impact of direct perfusion of WIN 55,212-2 into the frontal cortex on extracellular norepinephrine efflux was measured. Direct application of WIN 55,212-2 (100 microM) into the frontal cortex elicited a significant increase in extracellular norepinephrine efflux suggesting that activation of cortical cannabinoid receptors contributes to alterations in norepinephrine levels in this brain region. Finally, local administration of SR 141716A followed by local administration of WIN 55,212-2 revealed a paradoxical inhibition of norepinephrine efflux.

Dissociable prefrontal brain systems for attention and emotion

NASA Astrophysics Data System (ADS)

Yamasaki, Hiroshi; Labar, Kevin S.; McCarthy, Gregory

2002-08-01

The prefrontal cortex has been implicated in a variety of attentional, executive, and mnemonic mental operations, yet its functional organization is still highly debated. The present study used functional MRI to determine whether attentional and emotional functions are segregated into dissociable prefrontal networks in the human brain. Subjects discriminated infrequent and irregularly presented attentional targets (circles) from frequent standards (squares) while novel distracting scenes, parametrically varied for emotional arousal, were intermittently presented. Targets differentially activated middle frontal gyrus, posterior parietal cortex, and posterior cingulate gyrus. Novel distracters activated inferior frontal gyrus, amygdala, and fusiform gyrus, with significantly stronger activation evoked by the emotional scenes. The anterior cingulate gyrus was the only brain region with equivalent responses to attentional and emotional stimuli. These results show that attentional and emotional functions are segregated into parallel dorsal and ventral streams that extend into prefrontal cortex and are integrated in the anterior cingulate. These findings may have implications for understanding the neural dynamics underlying emotional distractibility on attentional tasks in affective disorders. novelty | prefrontal cortex | amygdala | cingulate gyrus

Visual Learning Alters the Spontaneous Activity of the Resting Human Brain: An fNIRS Study

PubMed Central

Niu, Haijing; Li, Hao; Sun, Li; Su, Yongming; Huang, Jing; Song, Yan

2014-01-01

Resting-state functional connectivity (RSFC) has been widely used to investigate spontaneous brain activity that exhibits correlated fluctuations. RSFC has been found to be changed along the developmental course and after learning. Here, we investigated whether and how visual learning modified the resting oxygenated hemoglobin (HbO) functional brain connectivity by using functional near-infrared spectroscopy (fNIRS). We demonstrate that after five days of training on an orientation discrimination task constrained to the right visual field, resting HbO functional connectivity and directed mutual interaction between high-level visual cortex and frontal/central areas involved in the top-down control were significantly modified. Moreover, these changes, which correlated with the degree of perceptual learning, were not limited to the trained left visual cortex. We conclude that the resting oxygenated hemoglobin functional connectivity could be used as a predictor of visual learning, supporting the involvement of high-level visual cortex and the involvement of frontal/central cortex during visual perceptual learning. PMID:25243168

Visual learning alters the spontaneous activity of the resting human brain: an fNIRS study.

PubMed

Niu, Haijing; Li, Hao; Sun, Li; Su, Yongming; Huang, Jing; Song, Yan

2014-01-01

Resting-state functional connectivity (RSFC) has been widely used to investigate spontaneous brain activity that exhibits correlated fluctuations. RSFC has been found to be changed along the developmental course and after learning. Here, we investigated whether and how visual learning modified the resting oxygenated hemoglobin (HbO) functional brain connectivity by using functional near-infrared spectroscopy (fNIRS). We demonstrate that after five days of training on an orientation discrimination task constrained to the right visual field, resting HbO functional connectivity and directed mutual interaction between high-level visual cortex and frontal/central areas involved in the top-down control were significantly modified. Moreover, these changes, which correlated with the degree of perceptual learning, were not limited to the trained left visual cortex. We conclude that the resting oxygenated hemoglobin functional connectivity could be used as a predictor of visual learning, supporting the involvement of high-level visual cortex and the involvement of frontal/central cortex during visual perceptual learning.

How task demands shape brain responses to visual food cues.

PubMed

Pohl, Tanja Maria; Tempelmann, Claus; Noesselt, Toemme

2017-06-01

Several previous imaging studies have aimed at identifying the neural basis of visual food cue processing in humans. However, there is little consistency of the functional magnetic resonance imaging (fMRI) results across studies. Here, we tested the hypothesis that this variability across studies might - at least in part - be caused by the different tasks employed. In particular, we assessed directly the influence of task set on brain responses to food stimuli with fMRI using two tasks (colour vs. edibility judgement, between-subjects design). When participants judged colour, the left insula, the left inferior parietal lobule, occipital areas, the left orbitofrontal cortex and other frontal areas expressed enhanced fMRI responses to food relative to non-food pictures. However, when judging edibility, enhanced fMRI responses to food pictures were observed in the superior and middle frontal gyrus and in medial frontal areas including the pregenual anterior cingulate cortex and ventromedial prefrontal cortex. This pattern of results indicates that task sets can significantly alter the neural underpinnings of food cue processing. We propose that judging low-level visual stimulus characteristics - such as colour - triggers stimulus-related representations in the visual and even in gustatory cortex (insula), whereas discriminating abstract stimulus categories activates higher order representations in both the anterior cingulate and prefrontal cortex. Hum Brain Mapp 38:2897-2912, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

A Postmortem Study of Frontal and Temporal Gyri Thickness and Cell Number in Human Obesity.

PubMed

Gómez-Apo, Erick; García-Sierra, Adrián; Silva-Pereyra, Juan; Soto-Abraham, Virgilia; Mondragón-Maya, Alejandra; Velasco-Vales, Verónica; Pescatello, Linda S

2018-01-01

This study aimed to compare cortex thickness and neuronal cell density in postmortem brain tissue from people with overweight or obesity and normal weight. The cortex thickness and neuron density of eight donors with overweight or obesity (mean = 31.6 kg/m 2 ; SD = 4.35; n = 8; 6 male) and eight donors with normal weight (mean = 21.8 kg/m 2 ; SD = 1.5; n = 8; 5 male) were compared. All participants were Mexican and lived in Mexico City. Randomly selected thickness measures of different cortex areas from the frontal and temporal lobes were analyzed based on high-resolution real-size photographs. A histological analysis of systematic-random fields was used to quantify the number of neurons in postmortem left and right of the first, second, and third gyri of frontal and temporal lobe brain samples. No statistical difference was found in cortical thickness between donors with overweight or obesity and individuals with normal weight. A smaller number of neurons was found among the donors with overweight or obesity than the donors with normal weight at different frontal and temporal areas. A lower density of neurons is associated with overweight or obesity. The morphological basis for structural brain changes in obesity requires further investigation. © 2017 The Obesity Society.

Auditory and visual connectivity gradients in frontoparietal cortex

PubMed Central

Hellyer, Peter J.; Wise, Richard J. S.; Leech, Robert

2016-01-01

Abstract A frontoparietal network of brain regions is often implicated in both auditory and visual information processing. Although it is possible that the same set of multimodal regions subserves both modalities, there is increasing evidence that there is a differentiation of sensory function within frontoparietal cortex. Magnetic resonance imaging (MRI) in humans was used to investigate whether different frontoparietal regions showed intrinsic biases in connectivity with visual or auditory modalities. Structural connectivity was assessed with diffusion tractography and functional connectivity was tested using functional MRI. A dorsal–ventral gradient of function was observed, where connectivity with visual cortex dominates dorsal frontal and parietal connections, while connectivity with auditory cortex dominates ventral frontal and parietal regions. A gradient was also observed along the posterior–anterior axis, although in opposite directions in prefrontal and parietal cortices. The results suggest that the location of neural activity within frontoparietal cortex may be influenced by these intrinsic biases toward visual and auditory processing. Thus, the location of activity in frontoparietal cortex may be influenced as much by stimulus modality as the cognitive demands of a task. It was concluded that stimulus modality was spatially encoded throughout frontal and parietal cortices, and was speculated that such an arrangement allows for top–down modulation of modality‐specific information to occur within higher‐order cortex. This could provide a potentially faster and more efficient pathway by which top–down selection between sensory modalities could occur, by constraining modulations to within frontal and parietal regions, rather than long‐range connections to sensory cortices. Hum Brain Mapp 38:255–270, 2017. © 2016 Wiley Periodicals, Inc. PMID:27571304

Energy metabolism of rat cerebral cortex, hypothalamus and hypophysis during ageing.

PubMed

Villa, R F; Ferrari, F; Gorini, A

2012-12-27

Ageing is one of the main risk factors for brain disorders. According to the neuroendocrine theory, ageing modifies the sensitivity of hypothalamus-pituitary-adrenal axis to homoeostatic signals coming from the cerebral cortex. The relationships between the energy metabolism of these areas have not been considered yet, in particular with respect to ageing. For these reasons, this study was undertaken to systematically investigate in female Sprague-Dawley rats aged 4, 6, 12, 18, 24, 28 months and in 4-month-old male ones, the catalytic properties of energy-linked enzymes of the Krebs' cycle, electron transport chain, glutamate and related amino acids on different mitochondrial subpopulations, i.e. non-synaptic perikaryal and intra-synaptic (two types) mitochondria. The biochemical enzymatic pattern of these mitochondria shows different expression of the above-mentioned enzymatic activities in the investigated brain areas, including frontal cerebral cortex, hippocampus, striatum, hypothalamus and hypophysis. The study shows that: (i) the energy metabolism of the frontal cerebral cortex is poorly affected by physiological ageing; (ii) the biochemical machinery of non-synaptic perikaryal mitochondria is differently expressed in the considered brain areas; (iii) at 4-6 months, hypothalamus and hypophysis possess lower oxidative metabolism with respect to the frontal cerebral cortex while (iv), during ageing, the opposite situation occurs. We hypothesised that these metabolic modifications likely try to grant HPA functionality in response to the incoming external stress stimuli increased during ageing. It is particularly notable that age-related changes in brain bioenergetics and in mitochondrial functionality may be considered as remarkable factors during physiological ageing and should play important roles in predisposing the brain to physiopathological events, tightly related to molecular mechanisms evoked for pharmacological treatments. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

Age-related differences in the brain areas outside the classical language areas among adults using category decision task.

PubMed

Cho, Yong Won; Song, Hui-Jin; Lee, Jae Jun; Lee, Joo Hwa; Lee, Hui Joong; Yi, Sang Doe; Chang, Hyuk Won; Berl, Madison M; Gaillard, William D; Chang, Yongmin

2012-03-01

Older adults perform much like younger adults on language. This similar level of performance, however, may come about through different underlying brain processes. In the present study, we evaluated age-related differences in the brain areas outside the typical language areas among adults using a category decision task. Our results showed that similar activation patterns were found in classical language processing areas across the three age groups although regional lateralization indices in Broca's and Wernicke's areas decreased with age. The greatest differences, however, among the three groups were found primarily in the brain areas not associated with core language functioning including the hippocampus, middle frontal gyrus, ventromedial frontal cortex, medial superior parietal cortex and posterior cingulate cortex. Therefore, the non-classical language areas may exhibit an age-related difference between three age groups while the subjects show a similar activation pattern in the core, primary language processing during a semantic decision task. Copyright © 2012 Elsevier Inc. All rights reserved.

Brain Hemispheric Differences in the Neurochemical Effects of Lead, Prenatal Stress, and the Combination and Their Amelioration by Behavioral Experience

PubMed Central

Cory-Slechta, Deborah A.

2013-01-01

Brain lateralization, critical to mediation of cognitive functions and to “multitasking,” is disrupted in conditions such as attention deficit disorder and schizophrenia. Both low-level lead (Pb) exposure and prenatal stress (PS) have been associated with mesocorticolimbic system–mediated executive-function cognitive and attention deficits. Mesocorticolimbic systems demonstrate significant laterality. Thus, altered brain lateralization could play a role in this behavioral toxicity. This study examined laterality of mesocorticolimbic monoamines (frontal cortex, nucleus accumbens, striatum, midbrain) and amino acids (frontal cortex) in male and female rats subjected to lifetime Pb exposure (0 or 50 ppm in drinking water), PS (restraint stress on gestational days 16–17), or the combination with and without repeated learning behavioral experience. Control males exhibited prominent laterality, particularly in midbrain and also in frontal cortex and striatum; females exhibited less laterality, and this was primarily striatal. Lateralized Pb ± PS induced neurotransmitter changes were assessed only in males because of limited sample sizes of Pb + PS females. In males, Pb ± PS changes occurred in left hemisphere of frontal cortex and right hemisphere of midbrain. Behavioral experience modified the laterality of Pb ± PS–induced neurotransmitter changes in a region-dependent manner. Notably, behavioral experience eliminated Pb ± PS neurotransmitter changes in males. These findings underscore the critical need to evaluate both sexes and brain hemispheres for the mechanistic understanding of sex-dependent differences in neuro- and behavioral toxicity. Furthermore, assessment of central nervous system mechanisms in the absence of behavioral experience, shown here for males, may constitute less relevant models of human health effects. PMID:23358193

Emotion regulation in the brain: conceptual issues and directions for developmental research.

PubMed

Lewis, Marc D; Stieben, Jim

2004-01-01

Emotion regulation cannot be temporally distinguished from emotion in the brain, but activation patterns in prefrontal cortex appear to mediate cognitive control during emotion episodes. Frontal event-related potentials (ERPs) can tap cognitive control hypothetically mediated by the anterior cingulate cortex, and developmentalists have used these to differentiate age, individual, and emotion-valence factors. Extending this approach, the present article outlines a research strategy for studying emotion regulation in children by combining emotion induction with a go/no-go task known to produce frontal ERPs. Preliminary results indicate that medial-frontal ERP amplitudes diminish with age but become more sensitive to anxiety, and internalizing children show higher amplitudes than noninternalizing children, especially when anxious. These results may reflect age and individual differences in the effortful regulation of negative emotion.

Brain Aging and AD-Like Pathology in Streptozotocin-Induced Diabetic Rats

PubMed Central

Wang, Jian-Qin; Yin, Jie; Song, Yan-Feng; Zhang, Lang; Ren, Ying-Xiang; Wang, De-Gui; Gao, Li-Ping; Jing, Yu-Hong

2014-01-01

Objective. Numerous epidemiological studies have linked diabetes mellitus (DM) with an increased risk of developing Alzheimer's disease (AD). However, whether or not diabetic encephalopathy shows AD-like pathology remains unclear. Research Design and Methods. Forebrain and hippocampal volumes were measured using stereology in serial coronal sections of the brain in streptozotocin- (STZ-) induced rats. Neurodegeneration in the frontal cortex, hypothalamus, and hippocampus was evaluated using Fluoro-Jade C (FJC). Aβ aggregation in the frontal cortex and hippocampus was tested using immunohistochemistry and ELISA. Dendritic spine density in the frontal cortex and hippocampus was measured using Golgi staining, and western blot was conducted to detect the levels of synaptophysin. Cognitive ability was evaluated through the Morris water maze and inhibitory avoidant box. Results. Rats are characterized by insulin deficiency accompanied with polydipsia, polyphagia, polyuria, and weight loss after STZ injection. The number of FJC-positive cells significantly increased in discrete brain regions of the diabetic rats compared with the age-matched control rats. Hippocampal atrophy, Aβ aggregation, and synapse loss were observed in the diabetic rats compared with the control rats. The learning and memory of the diabetic rats decreased compared with those of the age-matched control rats. Conclusions. Our results suggested that aberrant metabolism induced brain aging as characterized by AD-like pathologies. PMID:25197672

The Modulatory Properties of Chronic Antidepressant Drugs Treatment on the Brain Chemokine - Chemokine Receptor Network: A Molecular Study in an Animal Model of Depression.

PubMed

Trojan, Ewa; Ślusarczyk, Joanna; Chamera, Katarzyna; Kotarska, Katarzyna; Głombik, Katarzyna; Kubera, Marta; Basta-Kaim, Agnieszka

2017-01-01

An increasing number of studies indicate that the chemokine system may be the third major communication system of the brain. Therefore, the role of the chemokine system in the development of brain disorders, including depression, has been recently proposed. However, little is known about the impact of the administration of various antidepressant drugs on the brain chemokine - chemokine receptor axis. In the present study, we used an animal model of depression based on the prenatal stress procedure. We determined whether chronic treatment with tianeptine, venlafaxine, or fluoxetine influenced the evoked by prenatal stress procedure changes in the mRNA and protein levels of the homeostatic chemokines, CXCL12 (SDF-1α), CX3CL1 (fractalkine) and their receptors, in the hippocampus and frontal cortex. Moreover, the impact of mentioned antidepressants on the TGF-β, a molecular pathway related to fractalkine receptor (CX3CR1), was explored. We found that prenatal stress caused anxiety and depressive-like disturbances in adult offspring rats, which were normalized by chronic antidepressant treatment. Furthermore, we showed the stress-evoked CXCL12 upregulation while CXCR4 downregulation in hippocampus and frontal cortex. CXCR7 expression was enhanced in frontal cortex but not hippocampus. Furthermore, the levels of CX3CL1 and CX3CR1 were diminished by prenatal stress in the both examined brain areas. The mentioned changes were normalized with various potency by chronic administration of tested antidepressants. All drugs in hippocampus, while tianeptine and venlafaxine in frontal cortex normalized the CXCL12 level in prenatally stressed offspring. Moreover, in hippocampus only fluoxetine enhanced CXCR4 level, while fluoxetine and tianeptine diminished CXCR7 level in frontal cortex. Additionally, the diminished by prenatal stress levels of CX3CL1 and CX3CR1 in the both examined brain areas were normalized by chronic tianeptine and partially fluoxetine administration. Tianeptine modulate also brain TGF-β signaling in the prenatal stress-induced animal model of depression. Our results provide new evidence that not only prenatal stress-induced behavioral disturbances but also changes of CXCL12 and their receptor and at less extend in CX3CL1-CX3CR1 expression may be normalized by chronic antidepressant drug treatment. In particular, the effect on the CXCL12 and their CXCR4 and CXCR7 receptors requires additional studies to elucidate the possible biological consequences.

Acute seizure activity promotes lipid peroxidation, increased nitrite levels and adaptive pathways against oxidative stress in the frontal cortex and striatum

PubMed Central

Júnior, Hélio Vitoriano Nobre; de França Fonteles, Marta Maria

2009-01-01

Previous experiments have shown that the generation of free radicals in rat brain homogenates is increased following pilocarpine-induced seizures and status epilepticus (SE). This study was aimed at investigating the changes in neurochemical mechanisms such as lipid peroxidation levels, nitrite content, glutathione reduced (GSH) concentration, superoxide dismutase and catalase activities in the frontal cortex and the striatum of Wistar adult rats after seizures and SE induced by pilocarpine. The control group was treated with 0.9% saline and another group of rats received pilocarpine (400 mg/kg, i.p.). Both groups were sacrificed 24 h after the treatments. Lipid peroxidation level, nitrite content, GSH concentration and enzymatic activities were measured by using spectrophotometric methods. Our findings showed that pilocarpine administration and its resulting seizures and SE produced a significant increase of lipid peroxidation level in the striatum (47%) and frontal cortex (59%). Nitrite contents increased 49% and 73% in striatum and frontal cortex in pilocarpine group, respectively. In GSH concentrations were decreases of 54% and 58% in the striatum and frontal cortex in pilocarpine group, respectively. The catalase activity increased 39% and 49% in the striatum and frontal cortex, respectively. The superoxide dismutase activity was not altered in the striatum, but it was present at a 24% increase in frontal cortex. These results suggest that there is a direct relationship between the lipid peroxidation and nitrite contents during epileptic activity that can be responsible for the superoxide dismutase and catalase enzymatic activity changes observed during the establishment of seizures and SE induced by pilocarpine. PMID:20592767

Brain activation for reading and listening comprehension: An fMRI study of modality effects and individual differences in language comprehension

PubMed Central

Buchweitz, Augusto; Mason, Robert A.; Tomitch, Lêda M. B.; Just, Marcel Adam

2010-01-01

The study compared the brain activation patterns associated with the comprehension of written and spoken Portuguese sentences. An fMRI study measured brain activity while participants read and listened to sentences about general world knowledge. Participants had to decide if the sentences were true or false. To mirror the transient nature of spoken sentences, visual input was presented in rapid serial visual presentation format. The results showed a common core of amodal left inferior frontal and middle temporal gyri activation, as well as modality specific brain activation associated with listening and reading comprehension. Reading comprehension was associated with more left-lateralized activation and with left inferior occipital cortex (including fusiform gyrus) activation. Listening comprehension was associated with extensive bilateral temporal cortex activation and more overall activation of the whole cortex. Results also showed individual differences in brain activation for reading comprehension. Readers with lower working memory capacity showed more activation of right-hemisphere areas (spillover of activation) and more activation in the prefrontal cortex, potentially associated with more demand placed on executive control processes. Readers with higher working memory capacity showed more activation in a frontal-posterior network of areas (left angular and precentral gyri, and right inferior frontal gyrus). The activation of this network may be associated with phonological rehearsal of linguistic information when reading text presented in rapid serial visual format. The study demonstrates the modality fingerprints for language comprehension and indicates how low- and high working memory capacity readers deal with reading text presented in serial format. PMID:21526132

Activation of sensory cortex by imagined genital stimulation: an fMRI analysis.

PubMed

Wise, Nan J; Frangos, Eleni; Komisaruk, Barry R

2016-01-01

During the course of a previous study, our laboratory made a serendipitous finding that just thinking about genital stimulation resulted in brain activations that overlapped with, and differed from, those generated by physical genital stimulation. This study extends our previous findings by further characterizing how the brain differentially processes physical 'touch' stimulation and 'imagined' stimulation. Eleven healthy women (age range 29-74) participated in an fMRI study of the brain response to imagined or actual tactile stimulation of the nipple and clitoris. Two additional conditions - imagined dildo self-stimulation and imagined speculum stimulation - were included to characterize the effects of erotic versus non-erotic imagery. Imagined and tactile self-stimulation of the nipple and clitoris each activated the paracentral lobule (the genital region of the primary sensory cortex) and the secondary somatosensory cortex. Imagined self-stimulation of the clitoris and nipple resulted in greater activation of the frontal pole and orbital frontal cortex compared to tactile self-stimulation of these two bodily regions. Tactile self-stimulation of the clitoris and nipple activated the cerebellum, primary somatosensory cortex (hand region), and premotor cortex more than the imagined stimulation of these body regions. Imagining dildo stimulation generated extensive brain activation in the genital sensory cortex, secondary somatosensory cortex, hippocampus, amygdala, insula, nucleus accumbens, and medial prefrontal cortex, whereas imagining speculum stimulation generated only minimal activation. The present findings provide evidence of the potency of imagined stimulation of the genitals and that the following brain regions may participate in erogenous experience: primary and secondary sensory cortices, sensory-motor integration areas, limbic structures, and components of the 'reward system'. In addition, these results suggest a mechanism by which some individuals may be able to generate orgasm by imagery in the absence of physical stimulation.

Dyslexic children lack word selectivity gradients in occipito-temporal and inferior frontal cortex.

PubMed

Olulade, O A; Flowers, D L; Napoliello, E M; Eden, G F

2015-01-01

fMRI studies using a region-of-interest approach have revealed that the ventral portion of the left occipito-temporal cortex, which is specialized for orthographic processing of visually presented words (and includes the so-called "visual word form area", VWFA), is characterized by a posterior-to-anterior gradient of increasing selectivity for words in typically reading adults, adolescents, and children (e.g. Brem et al., 2006, 2009). Similarly, the left inferior frontal cortex (IFC) has been shown to exhibit a medial-to-lateral gradient of print selectivity in typically reading adults (Vinckier et al., 2007). Functional brain imaging studies of dyslexia have reported relative underactivity in left hemisphere occipito-temporal and inferior frontal regions using whole-brain analyses during word processing tasks. Hence, the question arises whether gradient sensitivities in these regions are altered in dyslexia. Indeed, a region-of-interest analysis revealed the gradient-specific functional specialization in the occipito-temporal cortex to be disrupted in dyslexic children (van der Mark et al., 2009). Building on these studies, we here (1) investigate if a word-selective gradient exists in the inferior frontal cortex in addition to the occipito-temporal cortex in normally reading children, (2) compare typically reading with dyslexic children, and (3) examine functional connections between these regions in both groups. We replicated the previously reported anterior-to-posterior gradient of increasing selectivity for words in the left occipito-temporal cortex in typically reading children, and its absence in the dyslexic children. Our novel finding is the detection of a pattern of increasing selectivity for words along the medial-to-lateral axis of the left inferior frontal cortex in typically reading children and evidence of functional connectivity between the most lateral aspect of this area and the anterior aspects of the occipito-temporal cortex. We report absence of an IFC gradient and connectivity between the lateral aspect of the IFC and the anterior occipito-temporal cortex in the dyslexic children. Together, our results provide insights into the source of the anomalies reported in previous studies of dyslexia and add to the growing evidence of an orthographic role of IFC in reading.

An fMRI study of differences in brain activity among elite, expert, and novice archers at the moment of optimal aiming.

PubMed

Kim, Woojong; Chang, Yongmin; Kim, Jingu; Seo, Jeehye; Ryu, Kwangmin; Lee, Eunkyung; Woo, Minjung; Janelle, Christopher M

2014-12-01

We investigated brain activity in elite, expert, and novice archers during a simulated archery aiming task to determine whether neural correlates of performance differ by skill level. Success in shooting sports depends on complex mental routines just before the shot, when the brain prepares to execute the movement. During functional magnetic resonance imaging, 40 elite, expert, or novice archers aimed at a simulated 70-meter-distant target and pushed a button when they mentally released the bowstring. At the moment of optimal aiming, the elite and expert archers relied primarily on a dorsal pathway, with greatest activity in the occipital lobe, temporoparietal lobe, and dorsolateral pre-motor cortex. The elites showed activity in the supplementary motor area, temporoparietal area, and cerebellar dentate, while the experts showed activity only in the superior frontal area. The novices showed concurrent activity in not only the dorsolateral pre-motor cortex but also the ventral pathways linked to the ventrolateral pre-motor cortex. The novices exhibited broad activity in the superior frontal area, inferior frontal area, ventral prefrontal cortex, primary motor cortex, superior parietal lobule, and primary somatosensory cortex. The more localized neural activity of elite and expert archers than novices permits greater efficiency in the complex processes subserved by these regions. The elite group's high activity in the cerebellar dentate indicates that the cerebellum is involved in automating simultaneous movements by integrating the sensorimotor memory enabled by greater expertise in self-paced aiming tasks. A companion article comments on and generalizes our findings.

Development of a neurofeedback protocol targeting the frontal pole using near-infrared spectroscopy.

PubMed

Kinoshita, Akihide; Takizawa, Ryu; Yahata, Noriaki; Homae, Fumitaka; Hashimoto, Ryuichiro; Sakakibara, Eisuke; Kawasaki, Shingo; Nishimura, Yukika; Koike, Shinsuke; Kasai, Kiyoto

2016-11-01

Neurofeedback has been studied with the aim of controlling cerebral activity. Near-infrared spectroscopy is a non-invasive neuroimaging technique used for measuring hemoglobin concentration changes in cortical surface areas with high temporal resolution. Thus, near-infrared spectroscopy may be useful for neurofeedback, which requires real-time feedback of repeated brain activation measurements. However, no study has specifically targeted neurofeedback, using near-infrared spectroscopy, in the frontal pole cortex. We developed an original near-infrared spectroscopy neurofeedback system targeting the frontal pole cortex. Over a single day of testing, each healthy participant (n = 24) received either correct or incorrect (Sham) feedback from near-infrared spectroscopy signals, based on a crossover design. Under correct feedback conditions, significant activation was observed in the frontal pole cortex (P = 0.000073). Additionally, self-evaluation of control and metacognitive beliefs were associated with near-infrared spectroscopy signals (P = 0.006). The neurofeedback system developed in this study might be useful for developing control of frontal pole cortex activation. © 2016 The Authors. Psychiatry and Clinical Neurosciences © 2016 Japanese Society of Psychiatry and Neurology.

[Effects of shortened mandibular dental arch on human brain activity during chewing: an fMRI study].

PubMed

Shoi, Kazuhito

2014-03-01

According to the shortened dental arch concept, missing molars should not always be restored with prosthetic treatment. A shortened dental arch with missing molars is associated with a decrease in masticatory function. However, it is not known whether a shortened dental arch influences brain activity during chewing. This study aimed to clarify the effect of posterior arch length of mandibular bilateral distal extension removable partial dentures (RPDs) on brain activity during chewing. Eleven subjects with bilaterally missing mandibular molars (mean age, 66.1 years) participated in the study. RPDs with full dental arch and shortened dental arch were fabricated and brain activity during gum chewing under each dental condition was measured using functional magnetic resonance imaging. Brain activation during gum chewing with the full dental arch was observed in the middle frontal gyrus, primary sensorimotor cortex extending to the premotor cortex, supplementary motor area, putamen, insula and cerebellum. However, activation of the middle frontal gyrus was not observed during gum chewing with the shortened dental arch. The results of this study suggest that human brain activity during chewing in the middle frontal gyrus may be associated with chewing in the presence of the molar region.

Exploratory metabolomic analyses reveal compounds correlated with lutein concentration in frontal cortex, hippocampus, and occipital cortex of human infant brain

USDA-ARS?s Scientific Manuscript database

Lutein is a dietary carotenoid well known for its role as an antioxidant in the macula and recent reports implicate a role for lutein in cognitive function. Lutein is the dominant carotenoid in both pediatric and geriatric brain tissue. In addition, cognitive function in older adults correlated with...

Neurons in the Frontal Lobe Encode the Value of Multiple Decision Variables

PubMed Central

Kennerley, Steven W.; Dahmubed, Aspandiar F.; Lara, Antonio H.; Wallis, Jonathan D.

2009-01-01

A central question in behavioral science is how we select among choice alternatives to obtain consistently the most beneficial outcomes. Three variables are particularly important when making a decision: the potential payoff, the probability of success, and the cost in terms of time and effort. A key brain region in decision making is the frontal cortex as damage here impairs the ability to make optimal choices across a range of decision types. We simultaneously recorded the activity of multiple single neurons in the frontal cortex while subjects made choices involving the three aforementioned decision variables. This enabled us to contrast the relative contribution of the anterior cingulate cortex (ACC), the orbito-frontal cortex, and the lateral prefrontal cortex to the decision-making process. Neurons in all three areas encoded value relating to choices involving probability, payoff, or cost manipulations. However, the most significant signals were in the ACC, where neurons encoded multiplexed representations of the three different decision variables. This supports the notion that the ACC is an important component of the neural circuitry underlying optimal decision making. PMID:18752411

Downregulation of the posterior medial frontal cortex prevents social conformity.

PubMed

Klucharev, Vasily; Munneke, Moniek A M; Smidts, Ale; Fernández, Guillén

2011-08-17

We often change our behavior to conform to real or imagined group pressure. Social influence on our behavior has been extensively studied in social psychology, but its neural mechanisms have remained largely unknown. Here we demonstrate that the transient downregulation of the posterior medial frontal cortex by theta-burst transcranial magnetic stimulation reduces conformity, as indicated by reduced conformal adjustments in line with group opinion. Both the extent and probability of conformal behavioral adjustments decreased significantly relative to a sham and a control stimulation over another brain area. The posterior part of the medial frontal cortex has previously been implicated in behavioral and attitudinal adjustments. Here, we provide the first interventional evidence of its critical role in social influence on human behavior.

Neural correlates of prospective memory impairments in schizophrenia.

PubMed

Chen, Xing-jie; Wang, Ya; Wang, Yi; Yang, Tian-xiao; Zou, Lai-quan; Huang, Jia; Li, Feng-hua; Chen, An-tao; Wang, Wei-hong; Zheng, Han-feng; Cheung, Eric F C; Shum, David H K; Chan, Raymond C K

2016-02-01

Prospective memory (PM) refers to the ability to remember to carry out intended actions after a delay. PM impairments are common in schizophrenia patients and are thought to be related to their prefrontal cortex dysfunction; however, this has not yet been examined directly in the research literature. The current study aimed to examine abnormalities in brain activation during PM task performance in schizophrenia patients. Twenty-two schizophrenia patients and 25 matched healthy controls were scanned in a 3-T MRI machine while performing a PM task. The results showed that compared to the healthy controls, schizophrenia patients performed significantly worse on the PM task. Furthermore, they exhibited decreased brain activation in frontal cortex including the right superior frontal gyri (Brodmann area 10), and other related brain areas like the anterior cingulate gyrus, parietal and temporal cortex, including precuneus, and some subcortext, including parahippocampal gyrus and putamen. These findings confirm the involvement and importance of the prefrontal cortex in PM and show evidence of hypofrontality in schizophrenia patients while performing a PM task. PsycINFO Database Record (c) 2016 APA, all rights reserved.

Brain activity in the right-frontal pole and lateral occipital cortex predicts successful post-operatory outcome after surgery for anterior glenoumeral instability.

PubMed

Zanchi, Davide; Cunningham, Gregory; Lädermann, Alexandre; Ozturk, Mehmet; Hoffmeyer, Pierre; Haller, Sven

2017-03-29

Shoulder apprehension is more complex than a pure mechanical problem of the shoulder, creating a scar at the brain level that prevents the performance of specific movements. Surgery corrects for shoulder instability at the physical level, but a re-dislocation within the first year is rather common. Predicting which patient will be likely to have re-dislocation is therefore crucial. We hypothesized that the assessment of neural activity at baseline and follow-up is the key factor to predict the post-operatory outcome. 13 patients with shoulder apprehension (30.03 ± 7.64 years) underwent clinical and fMRI examination before and one year after surgery for shoulder dislocation contrasting apprehension cue videos and control videos. Data analyses included task-related general linear model (GLM) and correlations imaging results with clinical scores. Clinical examination showed decreased pain and increased shoulder functions for post-op vs. pre-op. Coherently, GLM results show decreased activation of the left pre-motor cortex for post-surgery vs. pre-surgery. Right-frontal pole and right-occipital cortex activity predicts good recovery of shoulder function measured by STT. Our findings demonstrate that beside physical changes, changes at the brain level also occur one year after surgery. In particular, decreased activity in pre-motor and orbito-frontal cortex is key factor for a successful post-operatory outcome.

Magnetoencephalography evidence for different brain subregions serving two musical cultures.

PubMed

Matsunaga, Rie; Yokosawa, Koichi; Abe, Jun-ichi

2012-12-01

Individuals who have been exposed to two different musical cultures (bimusicals) can be differentiated from those exposed to only one musical culture (monomusicals). Just as bilingual speakers handle the distinct language-syntactic rules of each of two languages, bimusical listeners handle two distinct musical-syntactic rules (e.g., tonal schemas) in each musical culture. This study sought to determine specific brain activities that contribute to differentiating two culture-specific tonal structures. We recorded magnetoencephalogram (MEG) responses of bimusical Japanese nonmusicians and amateur musicians as they monitored unfamiliar Western melodies and unfamiliar, but traditional, Japanese melodies, both of which contained tonal deviants (out-of-key tones). Previous studies with Western monomusicals have shown that tonal deviants elicit an early right anterior negativity (mERAN) originating in the inferior frontal cortex. In the present study, tonal deviants in both Western and Japanese melodies elicited mERANs with characteristics fitted by dipoles around the inferior frontal gyrus in the right hemisphere and the premotor cortex in the left hemisphere. Comparisons of the nature of mERAN activity to Western and Japanese melodies showed differences in the dipoles' locations but not in their peak latency or dipole strength. These results suggest that the differentiation between a tonal structure of one culture and that of another culture correlates with localization differences in brain subregions around the inferior frontal cortex and the premotor cortex. Copyright © 2012 Elsevier Ltd. All rights reserved.

Long-range functional interactions of anterior insula and medial frontal cortex are differently modulated by visuospatial and inductive reasoning tasks.

PubMed

Ebisch, Sjoerd J H; Mantini, Dante; Romanelli, Roberta; Tommasi, Marco; Perrucci, Mauro G; Romani, Gian Luca; Colom, Roberto; Saggino, Aristide

2013-09-01

The brain is organized into functionally specific networks as characterized by intrinsic functional relationships within discrete sets of brain regions. However, it is poorly understood whether such functional networks are dynamically organized according to specific task-states. The anterior insular cortex (aIC)-dorsal anterior cingulate cortex (dACC)/medial frontal cortex (mFC) network has been proposed to play a central role in human cognitive abilities. The present functional magnetic resonance imaging (fMRI) study aimed at testing whether functional interactions of the aIC-dACC/mFC network in terms of temporally correlated patterns of neural activity across brain regions are dynamically modulated by transitory, ongoing task demands. For this purpose, functional interactions of the aIC-dACC/mFC network are compared during two distinguishable fluid reasoning tasks, Visualization and Induction. The results show an increased functional coupling of bilateral aIC with visual cortices in the occipital lobe during the Visualization task, whereas coupling of mFC with right anterior frontal cortex was enhanced during the Induction task. These task-specific modulations of functional interactions likely reflect ability related neural processing. Furthermore, functional connectivity strength between right aIC and right dACC/mFC reliably predicts general task performance. The findings suggest that the analysis of long-range functional interactions may provide complementary information about brain-behavior relationships. On the basis of our results, it is proposed that the aIC-dACC/mFC network contributes to the integration of task-common and task-specific information based on its within-network as well as its between-network dynamic functional interactions. Copyright © 2013 Elsevier Inc. All rights reserved.

Reduced Cortical Thickness and Increased Surface Area in Antisocial Personality Disorder

PubMed Central

Jiang, Weixiong; Li, Gang; Liu, Huasheng; Shi, Feng; Wang, Tao; Shen, Celina; Shen, Hui; Hu, Dewen; Wang, Wei; Shen, Dinggang

2016-01-01

Antisocial Personality Disorder (ASPD), one of whose characteristics is high impulsivity, is of great interest in the field of brain structure and function. However, little is known about possible impairments in the cortical anatomy in ASPD, in terms of cortical thickness and surface area, as well as their possible relationship with impulsivity. In this neuroimaging study, we first investigated the changes of cortical thickness and surface area in ASPD patients, in comparison to those of healthy controls, and then performed correlation analyses between these measures and the ability of impulse control. We found that ASPD patients showed thinner cortex while larger surface area in several specific brain regions, i.e., bilateral superior frontal gyrus, orbitofrontal and triangularis, insula cortex, precuneus, middle frontal gyrus, middle temporal gyrus, and left bank of superior temporal sulcus. In addition, we also found that the ability of impulse control was positively correlated with cortical thickness in the superior frontal gyrus, middle frontal gyrus, orbitofrontal cortex, pars triangularis, superior temporal gyrus, and insula cortex. To our knowledge, this study is the first to reveal simultaneous changes in cortical thickness and surface area in ASPD, as well as their relationship with impulsivity. These cortical structural changes may introduce uncontrolled and callous behavioral characteristic in ASPD patients, and these potential biomarkers may be very helpful in understanding the pathomechanism of ASPD. PMID:27600947

Functional Connectivity Bias in the Prefrontal Cortex of Psychopaths.

PubMed

Contreras-Rodríguez, Oren; Pujol, Jesus; Batalla, Iolanda; Harrison, Ben J; Soriano-Mas, Carles; Deus, Joan; López-Solà, Marina; Macià, Dídac; Pera, Vanessa; Hernández-Ribas, Rosa; Pifarré, Josep; Menchón, José M; Cardoner, Narcís

2015-11-01

Psychopathy is characterized by a distinctive interpersonal style that combines callous-unemotional traits with inflexible and antisocial behavior. Traditional emotion-based perspectives link emotional impairment mostly to alterations in amygdala-ventromedial frontal circuits. However, these models alone cannot explain why individuals with psychopathy can regularly benefit from emotional information when placed on their focus of attention and why they are more resistant to interference from nonaffective contextual cues. The present study aimed to identify abnormal or distinctive functional links between and within emotional and cognitive brain systems in the psychopathic brain to characterize further the neural bases of psychopathy. High-resolution anatomic magnetic resonance imaging with a functional sequence acquired in the resting state was used to assess 22 subjects with psychopathy and 22 control subjects. Anatomic and functional connectivity alterations were investigated first using a whole-brain analysis. Brain regions showing overlapping anatomic and functional changes were examined further using seed-based functional connectivity mapping. Subjects with psychopathy showed gray matter reduction involving prefrontal cortex, paralimbic, and limbic structures. Anatomic changes overlapped with areas showing increased degree of functional connectivity at the medial-dorsal frontal cortex. Subsequent functional seed-based connectivity mapping revealed a pattern of reduced functional connectivity of prefrontal areas with limbic-paralimbic structures and enhanced connectivity within the dorsal frontal lobe in subjects with psychopathy. Our results suggest that a weakened link between emotional and cognitive domains in the psychopathic brain may combine with enhanced functional connections within frontal executive areas. The identified functional alterations are discussed in the context of potential contributors to the inflexible behavior displayed by individuals with psychopathy. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Residual number processing in dyscalculia☆

PubMed Central

Cappelletti, Marinella; Price, Cathy J.

2013-01-01

Developmental dyscalculia – a congenital learning disability in understanding numerical concepts – is typically associated with parietal lobe abnormality. However, people with dyscalculia often retain some residual numerical abilities, reported in studies that otherwise focused on abnormalities in the dyscalculic brain. Here we took a different perspective by focusing on brain regions that support residual number processing in dyscalculia. All participants accurately performed semantic and categorical colour-decision tasks with numerical and non-numerical stimuli, with adults with dyscalculia performing slower than controls in the number semantic tasks only. Structural imaging showed less grey-matter volume in the right parietal cortex in people with dyscalculia relative to controls. Functional MRI showed that accurate number semantic judgements were maintained by parietal and inferior frontal activations that were common to adults with dyscalculia and controls, with higher activation for participants with dyscalculia than controls in the right superior frontal cortex and the left inferior frontal sulcus. Enhanced activation in these frontal areas was driven by people with dyscalculia who made faster rather than slower numerical decisions; however, activation could not be accounted for by response times per se, because it was greater for fast relative to slow dyscalculics but not greater for fast controls relative to slow dyscalculics. In conclusion, our results reveal two frontal brain regions that support efficient number processing in dyscalculia. PMID:24266008

Residual number processing in dyscalculia.

PubMed

Cappelletti, Marinella; Price, Cathy J

2014-01-01

Developmental dyscalculia - a congenital learning disability in understanding numerical concepts - is typically associated with parietal lobe abnormality. However, people with dyscalculia often retain some residual numerical abilities, reported in studies that otherwise focused on abnormalities in the dyscalculic brain. Here we took a different perspective by focusing on brain regions that support residual number processing in dyscalculia. All participants accurately performed semantic and categorical colour-decision tasks with numerical and non-numerical stimuli, with adults with dyscalculia performing slower than controls in the number semantic tasks only. Structural imaging showed less grey-matter volume in the right parietal cortex in people with dyscalculia relative to controls. Functional MRI showed that accurate number semantic judgements were maintained by parietal and inferior frontal activations that were common to adults with dyscalculia and controls, with higher activation for participants with dyscalculia than controls in the right superior frontal cortex and the left inferior frontal sulcus. Enhanced activation in these frontal areas was driven by people with dyscalculia who made faster rather than slower numerical decisions; however, activation could not be accounted for by response times per se, because it was greater for fast relative to slow dyscalculics but not greater for fast controls relative to slow dyscalculics. In conclusion, our results reveal two frontal brain regions that support efficient number processing in dyscalculia.

Compensatory brain activation in children with attention deficit/hyperactivity disorder during a simplified Go/No-go task.

PubMed

Ma, Jun; Lei, Du; Jin, Xingming; Du, Xiaoxia; Jiang, Fan; Li, Fei; Zhang, Yiwen; Shen, Xiaoming

2012-05-01

Given that a number of recent studies have shown attenuated brain activation in prefrontal regions in children with ADHD, it has been recognized as a disorder in executive function. However, fewer studies have focused exclusively on the compensatory brain activation in ADHD. The present study objective was to investigate the compensatory brain activation patterns during response inhibition (RI) processing in ADHD children. In this study, 15 ADHD children and 15 sex-, age-, and IQ-matched control children were scanned with a 3-T MRI equipment while performing a simplified letter Go/No-go task. The results showed more brain activation in the ADHD group compared with the control group, whereas the accuracy and reaction time of behavioral performance were the same. Children with ADHD did not activate the normal RI brain circuits, which are thought to be predominantly located in the right middle/inferior frontal gyrus (BA46/44), right inferior parietal regions (BA40), and pre-SMA(BA6), but instead, activated brain regions, such as the left inferior frontal cortex, the right inferior temporal cortex, the right precentral gyrus, the left postcentral gyrus, the inferior occipital cortex, the middle occipital cortex, the right calcarine, the right hippocampus, the right midbrain, and the cerebellum. Our conclusion is that children with ADHD tend to compensatorily use more posterior and diffusive brain regions to sustain normal RI function. © Springer-Verlag 2011

Preliminary report on macroscopic age changes in the human prosencephalon. A stereologic investigation.

PubMed

Eggers, R; Haug, H; Fischer, D

1984-01-01

The studies here reported were performed on the prosencephalons of 12 human brains between 37 and 86 years of age having no signs of neuropathological alteration. The evaluation was carried out on serial frontal sections with a mean thickness of 5 mm with stereological point counting procedures for volume and surface area. The results were mainly given in relative values since the range of variation is very high and the sample small. The aging process was evaluated with the aid of a linear regression function. The stereological investigation regarding the absolute values of volume and surface area (border face) of the macroscopical brain parts show a high interindividual variability. However, the relative volume of brain parts shows only small variations. Changes during aging could consequently only be revealed with the help of the relative values. The relative volumes and surface areas of the frontal lobe and the prosencephalic ganglia decrease with aging, while the parieto-occipital lobe and the striate cortex increase. However, if we refer these relative increases to the absolute decrease of brain volume, corresponding changes cannot be found in the parieto-occipital lobe until old age. The shrinkage of the frontal lobe, of the centrum semiovale and of the prosencephalic ganglia exceeds 10%. In the grays it is probably accompanied by a loss of neurons. The relative sizes of the surface area do not change significantly during aging with exception of the frontal cortex. The thickness of the cortex remains probably constant. The size of lateral ventricles increases with aging.

Thinking on luxury or pragmatic brand products: Brain responses to different categories of culturally based brands.

PubMed

Schaefer, Michael; Rotte, Michael

2007-08-24

Culturally based brands have a high impact on people's economic actions. Here we aimed to examine whether socioeconomic information conveyed by certain classes of brands (prestigious versus pragmatic classes) differentially evoke brain response. We presented icons of brands while recording subject's brain activity during a functional magnetic resonance imaging (fMRI) session. After the experiment, we asked subjects to assess the brands according to different characteristics. Results revealed an active network of bilateral superior frontal gyri, hippocampus and posterior cingulate related to familiar brands in general. Brands of the category sports and luxury activated regions in medial prefrontal cortex (MPFC) and precuneus. In contrast, brands rated as value products activated the left superior frontal gyrus and anterior cingulate cortex (ACC). The results suggest an active cortical network related to cognitive control for value brands and a network known to be associated with self-relevant processing for prestigious brands. We discuss the results as differential engagement of the prefrontal cortex depending on the attributed characteristic of a brand.

The effects of chronic stress on the human brain: From neurotoxicity, to vulnerability, to opportunity.

PubMed

Lupien, Sonia J; Juster, Robert-Paul; Raymond, Catherine; Marin, Marie-France

2018-04-01

For the last five decades, science has managed to delineate the mechanisms by which stress hormones can impact on the human brain. Receptors for glucocorticoids are found in the hippocampus, amygdala and frontal cortex, three brain regions involved in memory processing and emotional regulation. Studies have shown that chronic exposure to stress is associated with reduced volume of the hippocampus and that chronic stress can modulate volumes of both the amygdala and frontal cortex, suggesting neurotoxic effects of stress hormones on the brain. Yet, other studies report that exposure to early adversity and/or familial/social stressors can increase vulnerability to stress in adulthood. Models have been recently developed to describe the roles that neurotoxic and vulnerability effects can have on the developing brain. These models suggest that developing early stress interventions could potentially counteract the effects of chronic stress on the brain and results going along with this hypothesis are summarized. Copyright © 2018 Elsevier Inc. All rights reserved.

Adrenergic receptors in frontal cortex in human brain.

PubMed

Cash, R; Raisman, R; Ruberg, M; Agid, Y

1985-02-05

The binding of three adrenergic ligands ([3H]prazosin, [3H]clonidine, [3H]dihydroalprenolol) was studied in the frontal cortex of human brain. alpha 1-Receptors, labeled by [3H]prazosin, predominated. [3H]Clonidine bound to two classes of sites, one of high affinity and one of low affinity. Guanosine triphosphate appeared to lower the affinity of [3H]clonidine for its receptor. [3H]Dihydroalprenolol bound to three classes of sites: the beta 1-receptor, the beta 2-receptor and a receptor with low affinity which represented about 40% of the total binding, but which was probably a non-specific site; the beta 1/beta 2 ratio was 1/2.

Increased neuroinflammatory and arachidonic acid cascade markers, and reduced synaptic proteins, in the postmortem frontal cortex from schizophrenia patients

PubMed Central

Rao, Jagadeesh Sridhara; Kim, Hyung-Wook; Harry, Gaylia Jean; Rapoport, Stanley Isaac; Reese, Edmund Arthur

2013-01-01

Schizophrenia (SZ) is a progressive, neuropsychiatric disorder associated with cognitive impairment. A number of brain alterations have been linked to cognitive impairment, including neuroinflammation, excitotoxicity, increased arachidonic acid (AA) signaling and reduced synaptic protein. On this basis, we tested the hypothesis that SZ pathology is associated with these pathological brain changes. To do this, we examined postmortem frontal cortex from 10 SZ patients and 10 controls and measured protein and mRNA levels of cytokines, and astroglial, microglial, neuroinflammatory excitotoxic, AA cascade, apoptotic and synaptic markers. Mean protein and mRNA levels of interleukin-1β, tumor necrosis factor-α, glial acidic fibrillary protein (GFAP), a microglial marker CD11b, and nuclear factor kappa B subunits were significantly increased in SZ compared with control brain. Protein and mRNA levels of cytosolic and secretory phospholipase A2 and cyclooxygenase were significantly elevated in postmortem brains from SZ patients. N-methyl-D-aspartate receptor subunits 1 and 2B, inducible nitric oxide synthase and c-FOS were not significantly different. In addition, reduced protein and mRNA levels of brain-derived neurotrophic factor, synaptophysin and drebrin were found in SZ compared with control frontal cortex. Increased neuroinflammation and AA cascade enzyme markers with synaptic protein loss could promote disease progression and cognitive defects in SZ patients. Drugs that downregulate these changes might be considered for new therapies in SZ. PMID:23566496

Brain substrates of social decision-making in dual diagnosis: cocaine dependence and personality disorders.

PubMed

Verdejo-Garcia, Antonio; Verdejo-Román, Juan; Albein-Urios, Natalia; Martínez-González, José M; Soriano-Mas, Carles

2017-03-01

Cocaine dependence frequently co-occurs with personality disorders, leading to increased interpersonal problems and greater burden of disease. Personality disorders are characterised by patterns of thinking and feeling that divert from social expectations. However, the comorbidity between cocaine dependence and personality disorders has not been substantiated by measures of brain activation during social decision-making. We applied functional magnetic resonance imaging to compare brain activations evoked by a social decision-making task-the Ultimatum Game-in 24 cocaine dependents with personality disorders (CDPD), 19 cocaine dependents without comorbidities and 19 healthy controls. In the Ultimatum Game participants had to accept or reject bids made by another player to split monetary stakes. Offers varied in fairness (in fair offers the proposer shares ~50 percent of the money; in unfair offers the proposer shares <30 percent of the money), and participants were told that if they accept both players get the money, and if they reject both players lose it. We contrasted brain activations during unfair versus fair offers and accept versus reject choices. During evaluation of unfair offers CDPD displayed lower activation in the insula and the anterior cingulate cortex and higher activation in the lateral orbitofrontal cortex and superior frontal and temporal gyri. Frontal activations negatively correlated with emotion recognition. During rejection of offers CDPD displayed lower activation in the anterior cingulate cortex, striatum and midbrain. Dual diagnosis is linked to hypo-activation of the insula and anterior cingulate cortex and hyper-activation of frontal-temporal regions during social decision-making, which associates with poorer emotion recognition. © 2015 Society for the Study of Addiction.

Sex differences in impulsivity and brain morphometry in methamphetamine users

PubMed Central

Kogachi, Shannon; Chang, Linda; Alicata, Daniel; Cunningham, Eric; Ernst, Thomas

2016-01-01

Methamphetamine (METH) is an addictive stimulant, and METH users have abnormal brain structures and function. The aims of this study were to investigate the relationships between impulsivity, brain structures, and possible sex-specific differences between METH users and non-drug using Controls. Structural MRI and the Barratt Impulsiveness Scale (BIS) questionnaire were completed in 124 subjects: 62 METH (ages 41.2 ± 1.4 years, 34 males) and 62 Controls (ages 43.3 ± 2.3 years, 36 males). Independent and interactive effects of METH use status and sex were evaluated. Relationships between METH usage characteristics, brain morphometry, and impulsivity scores were examined. METH users had higher impulsivity scores, on both the Cognitive and Behavioral Factors from the BIS (p < 0.0001–0.0001). Compared with same-sex Controls, male METH users had larger, while female METH users had smaller, right superior frontal cortex (interaction-p = 0.0005). The male METH users with larger frontal volumes and female METH users with smaller or thinner frontal cortices had greater Cognitive impulsivity (interaction-p ≤ 0.05). Only female METH users showed relatively larger nucleus accumbens (interaction-p = 0.03). Greater impulsivity and thinner frontal cortices in METH users are validated. Larger superior frontal cortex in male METH users with greater cognitive impulsivity suggest decreased dendritic pruning during adolescence might have contributed to their impulsive and drug use behaviors. In the female METH users, smaller frontal cortices and the associated greater impulsivity suggest greater neurotoxicity to these brain regions, while their relatively larger nucleus accumbens suggest an estrogen-mediated neuroprotective glial response. Men and women may be affected differently by METH use. PMID:27095357

Sex differences in impulsivity and brain morphometry in methamphetamine users.

PubMed

Kogachi, Shannon; Chang, Linda; Alicata, Daniel; Cunningham, Eric; Ernst, Thomas

2017-01-01

Methamphetamine (METH) is an addictive stimulant, and METH users have abnormal brain structures and function. The aims of this study were to investigate the relationships between impulsivity, brain structures, and possible sex-specific differences between METH users and non-drug using Controls. Structural MRI and the Barratt Impulsiveness Scale (BIS) questionnaire were completed in 124 subjects: 62 METH (ages 41.2 ± 1.4 years, 34 males) and 62 Controls (ages 43.3 ± 2.3 years, 36 males). Independent and interactive effects of METH use status and sex were evaluated. Relationships between METH usage characteristics, brain morphometry, and impulsivity scores were examined. METH users had higher impulsivity scores, on both the Cognitive and Behavioral Factors from the BIS (p < 0.0001-0.0001). Compared with same-sex Controls, male METH users had larger, while female METH users had smaller, right superior frontal cortex (interaction-p = 0.0005). The male METH users with larger frontal volumes and female METH users with smaller or thinner frontal cortices had greater Cognitive impulsivity (interaction-p ≤ 0.05). Only female METH users showed relatively larger nucleus accumbens (interaction-p = 0.03). Greater impulsivity and thinner frontal cortices in METH users are validated. Larger superior frontal cortex in male METH users with greater cognitive impulsivity suggest decreased dendritic pruning during adolescence might have contributed to their impulsive and drug use behaviors. In the female METH users, smaller frontal cortices and the associated greater impulsivity suggest greater neurotoxicity to these brain regions, while their relatively larger nucleus accumbens suggest an estrogen-mediated neuroprotective glial response. Men and women may be affected differently by METH use.

Advances in understanding ventromedial prefrontal function: the accountant joins the executive.

PubMed

Fellows, Lesley K

2007-03-27

Studies of the brain basis of decision-making and economic behavior are providing a new perspective on the organization and functions of human prefrontal cortex. This line of inquiry has focused particularly on the ventral and medial portions of prefrontal cortex, arguably the most enigmatic regions of the "enigmatic frontal lobes." This review highlights recent advances in the cognitive neuroscience of decision making and neuroeconomics and discusses how these findings can inform clinical thinking about frontal lobe dysfunction.

A microdialysis study of the novel antiepileptic drug levetiracetam: extracellular pharmacokinetics and effect on taurine in rat brain

PubMed Central

Tong, X; Patsalos, P N

2001-01-01

Using a rat model which allows serial blood sampling and concurrent brain microdialysis sampling, we have investigated the temporal kinetic inter-relationship of levetiracetam in serum and brain extracellular fluid (frontal cortex and hippocampus) following systemic administration of levetiracetam, a new antiepileptic drug. Concurrent extracellular amino acid concentrations were also determined. After administration (40 or 80 mg kg−1), levetiracetam rapidly appeared in both serum (Tmax, 0.4 – 0.7 h) and extracellular fluid (Tmax, 2.0 – 2.5 h) and concentrations rose linearly and dose-dependently, suggesting that transport across the blood-brain barrier is rapid and not rate-limiting. The serum free fraction (free/total serum concentration ratio; mean±s.e.mean range 0.93 – 1.05) was independent of concentration and confirms that levetiracetam is not bound to blood proteins. The kinetic profiles for the hippocampus and frontal cortex were indistinguishable suggesting that levetiracetam distribution in the brain is not brain region specific. However, t1/2 values were significantly larger than those for serum (mean range, 3.0 – 3.3 h vs 2.1 – 2.3 h) and concentrations did not attain equilibrium with respect to serum. Levetiracetam (80 mg kg−1) was associated with a significant reduction in taurine in the hippocampus and frontal cortex. Other amino acids were unaffected by levetiracetam. Levetiracetam readily and rapidly enters the brain without regional specificity. Its prolonged efflux from and slow equilibration within the brain may explain, in part, its long duration of action. The concurrent changes in taurine may contribute to its mechanism of action. PMID:11454660

Neurochemical abnormalities in brains of renal failure patients treated by repeated hemodialysis.

PubMed

Perry, T L; Yong, V W; Kish, S J; Ito, M; Foulks, J G; Godolphin, W J; Sweeney, V P

1985-10-01

We examined autopsied brain from 10 patients with end-stage renal failure who had undergone repeated hemodialysis. Eight had classic symptoms, and two had suggestive symptoms of dialysis encephalopathy. Findings were compared with those in autopsied brain from control adults who had never been hemodialyzed. Mean gamma-aminobutyric acid (GABA) contents were significantly reduced in frontal and occipital cortex, cerebellar cortex, dentate nucleus, caudate nucleus, and medial-dorsal thalamus of the hemodialyzed patients, the reduction being greater than 40% in cerebral cortex and thalamus. Choline acetyltransferase activity was reduced by 25-35% in three cortical regions in the hemodialyzed patients. These two abnormalities were observed in the brain of each hemodialyzed patient, regardless of whether or not the patient died with unequivocal dialysis encephalopathy. Pyridoxal phosphate contents were substantially reduced in brains of the hemodialyzed patients, but metabolites of noradrenaline, 3,4-dihydroxyphenylethylamine (dopamine), and 5-hydroxytryptamine (serotonin) were present in normal amounts. Aluminum levels were abnormally high in frontal cortical gray matter in the hemodialyzed patients. Although this study does not clarify the role played by aluminum toxicity in the pathogenesis of dialysis encephalopathy, the abnormalities we found suggest the need for further neurochemical investigations in this disorder.

Reading a Suspenseful Literary Text Activates Brain Areas Related to Social Cognition and Predictive Inference

PubMed Central

Lehne, Moritz; Engel, Philipp; Rohrmeier, Martin; Menninghaus, Winfried; Jacobs, Arthur M.; Koelsch, Stefan

2015-01-01

Stories can elicit powerful emotions. A key emotional response to narrative plots (e.g., novels, movies, etc.) is suspense. Suspense appears to build on basic aspects of human cognition such as processes of expectation, anticipation, and prediction. However, the neural processes underlying emotional experiences of suspense have not been previously investigated. We acquired functional magnetic resonance imaging (fMRI) data while participants read a suspenseful literary text (E.T.A. Hoffmann's “The Sandman”) subdivided into short text passages. Individual ratings of experienced suspense obtained after each text passage were found to be related to activation in the medial frontal cortex, bilateral frontal regions (along the inferior frontal sulcus), lateral premotor cortex, as well as posterior temporal and temporo-parietal areas. The results indicate that the emotional experience of suspense depends on brain areas associated with social cognition and predictive inference. PMID:25946306

Bilingualism Alters Children's Frontal Lobe Functioning for Attentional Control

PubMed Central

Arredondo, Maria M.; Hu, Xiao-Su; Satterfield, Teresa; Kovelman, Ioulia

2017-01-01

Bilingualism is a typical linguistic experience, yet relatively little is known about its impact on children's cognitive and brain development. Theories of bilingualism suggest early dual-language acquisition can improve children's cognitive abilities, specifically those relying on frontal lobe functioning. While behavioral findings present much conflicting evidence, little is known about its effects on children's frontal lobe development. Using functional Near-Infrared Spectroscopy (fNIRS), the findings suggest that Spanish-English bilingual children (n=13, ages 7-13) had greater activation in left prefrontal cortex during a non-verbal attentional control task relative to age-matched English monolinguals. In contrast, monolinguals (n=14) showed greater right prefrontal activation than bilinguals. The present findings suggest early bilingualism yields significant changes to the functional organization of children's prefrontal cortex for attentional control and carry implications for understanding how early life experiences impact cognition and brain development. PMID:26743118

Expression and localization of aromatase P450AROM, estrogen receptor-α, and estrogen receptor-β in the developing fetal bovine frontal cortex.

PubMed

Peruffo, A; Giacomello, M; Montelli, S; Corain, L; Cozzi, B

2011-06-01

The enzyme aromatase (P450(AROM)) converts testosterone (T) into 17-β estradiol (E(2)) and is crucial for the control of development of the central nervous system during ontogenesis. The effects of E(2) in various brain areas are mediated by the estrogen receptor alpha (ER-α) and the estrogen receptor beta (ER-β). During fetal development, steroids are responsible for the sexual differentiation of the hypothalamus. Estrogens are also able to exert effects in other brain areas of the fetus including the frontal cortex, where they act through estrogen receptors (ERs) modulating cognitive function and affective behaviors. In this study we have determined the expression profiles of P450(AROM) and ERs in the fetal bovine frontal cortex by quantitative Real-Time PCR (qRT-PCR) throughout the prenatal development. The data show that the patterns of expression of both ERs are strongly correlated during pregnancy and increase in the last stage of gestation. On the contrary, the expression of P450(AROM) has no correlation with ERs expression and is not developmentally regulated. Moreover, we performed immunochemical studies showing that fetal neurons express P450(AROM) and the ERs. P450(AROM) is localized in the cytoplasm and only seldom present in the fine extensions of the cells; ER-α is detected predominantly in the soma whereas ER-β is only present in the nucleus of a few cells. This study provides new data on the development of the frontal cortex in a long gestation mammal with a large convoluted brain. Copyright © 2011 Elsevier Inc. All rights reserved.

Neurochemical differences in learning and memory paradigms among rats supplemented with anthocyanin-rich blueberry diets and exposed to acute doses of 56Fe particles

NASA Astrophysics Data System (ADS)

Poulose, Shibu M.; Rabin, Bernard M.; Bielinski, Donna F.; Kelly, Megan E.; Miller, Marshall G.; Thanthaeng, Nopporn; Shukitt-Hale, Barbara

2017-02-01

The protective effects of anthocyanin-rich blueberries (BB) on brain health are well documented and are particularly important under conditions of high oxidative stress, which can lead to "accelerated aging." One such scenario is exposure to space radiation, consisting of high-energy and -charge particles (HZE), which are known to cause cognitive dysfunction and deleterious neurochemical alterations. We recently tested the behavioral and neurochemical effects of acute exposure to HZE particles such as 56Fe, within 24-48 h after exposure, and found that radiation primarily affects memory and not learning. Importantly, we observed that specific brain regions failed to upregulate antioxidant and anti-inflammatory mechanisms in response to this insult. To further examine these endogenous response mechanisms, we have supplemented young rats with diets rich in BB, which are known to contain high amounts of antioxidant-phytochemicals, prior to irradiation. Exposure to 56Fe caused significant neurochemical changes in hippocampus and frontal cortex, the two critical regions of the brain involved in cognitive function. BB supplementation significantly attenuated protein carbonylation, which was significantly increased by exposure to 56Fe in the hippocampus and frontal cortex. Moreover, BB supplementation significantly reduced radiation-induced elevations in NADPH-oxidoreductase-2 (NOX2) and cyclooxygenase-2 (COX-2), and upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) in the hippocampus and frontal cortex. Overall results indicate that 56Fe particles may induce their toxic effects on hippocampus and frontal cortex by reactive oxygen species (ROS) overload, which can cause alterations in the neuronal environment, eventually leading to hippocampal neuronal death and subsequent impairment of cognitive function. Blueberry supplementation provides an effective preventative measure to reduce the ROS load on the CNS in an event of acute HZE exposure.

The Psychoactive Designer Drug and Bath Salt Constituent MDPV Causes Widespread Disruption of Brain Functional Connectivity

PubMed Central

Colon-Perez, Luis M; Tran, Kelvin; Thompson, Khalil; Pace, Michael C; Blum, Kenneth; Goldberger, Bruce A; Gold, Mark S; Bruijnzeel, Adriaan W; Setlow, Barry; Febo, Marcelo

2016-01-01

The abuse of ‘bath salts' has raised concerns because of their adverse effects, which include delirium, violent behavior, and suicide ideation in severe cases. The bath salt constituent 3,4-methylenedioxypyrovalerone (MDPV) has been closely linked to these and other adverse effects. The abnormal behavioral pattern produced by acute high-dose MDPV intake suggests possible disruptions of neural communication between brain regions. Therefore, we determined if MDPV exerts disruptive effects on brain functional connectivity, particularly in areas of the prefrontal cortex. Male rats were imaged following administration of a single dose of MDPV (0.3, 1.0, or 3.0 mg/kg) or saline. Resting state brain blood oxygenation level-dependent (BOLD) images were acquired at 4.7 T. To determine the role of dopamine transmission in MDPV-induced changes in functional connectivity, a group of rats received the dopamine D1/D2 receptor antagonist cis-flupenthixol (0.5 mg/kg) 30 min before MDPV. MDPV dose-dependently reduced functional connectivity. Detailed analysis of its effects revealed that connectivity between frontal cortical and striatal areas was reduced. This included connectivity between the prelimbic prefrontal cortex and other areas of the frontal cortex and the insular cortex with hypothalamic, ventral, and dorsal striatal areas. Although the reduced connectivity appeared widespread, connectivity between these regions and somatosensory cortex was not as severely affected. Dopamine receptor blockade did not prevent the MDPV-induced decrease in functional connectivity. The results provide a novel signature of MDPV's in vivo mechanism of action. Reduced brain functional connectivity has been reported in patients suffering from psychosis and has been linked to cognitive dysfunction, audiovisual hallucinations, and negative affective states akin to those reported for MDPV-induced intoxication. The present results suggest that disruption of functional connectivity networks involving frontal cortical and striatal regions could contribute to the adverse effects of MDPV. PMID:26997298

Intrinsic brain subsystem associated with dietary restraint, disinhibition and hunger: an fMRI study.

PubMed

Zhao, Jizheng; Li, Mintong; Zhang, Yi; Song, Huaibo; von Deneen, Karen M; Shi, Yinggang; Liu, Yijun; He, Dongjian

2017-02-01

Eating behaviors are closely related to body weight, and eating traits are depicted in three dimensions: dietary restraint, disinhibition, and hunger. The current study aims to explore whether these aspects of eating behaviors are related to intrinsic brain activation, and to further investigate the relationship between the brain activation relating to these eating traits and body weight, as well as the link between function connectivity (FC) of the correlative brain regions and body weight. Our results demonstrated positive associations between dietary restraint and baseline activation of the frontal and the temporal regions (i.e., food reward encoding) and the limbic regions (i.e., homeostatic control, including the hypothalamus). Disinhibition was positively associated with the activation of the frontal motivational system (i.e., OFC) and the premotor cortex. Hunger was positively related to extensive activations in the prefrontal, temporal, and limbic, as well as in the cerebellum. Within the brain regions relating to dietary restraint, weight status was negatively correlated with FC of the left middle temporal gyrus and left inferior temporal gyrus, and was positively associated with the FC of regions in the anterior temporal gyrus and fusiform visual cortex. Weight status was positively associated with the FC within regions in the prefrontal motor cortex and the right ACC serving inhibition, and was negatively related with the FC of regions in the frontal cortical-basal ganglia-thalamic circuits responding to hunger control. Our data depicted an association between intrinsic brain activation and dietary restraint, disinhibition, and hunger, and presented the links of their activations and FCs with weight status.

Brain gamma-aminobutyric acid deficiency in dialysis encephalopathy.

PubMed

Sweeney, V P; Perry, T L; Price, J D; Reeve, C E; Godolphin, W J; Kish, S J

1985-02-01

We measured levels of gamma-aminobutyric acid (GABA) in the CSF and in the autopsied brain of patients with dialysis encephalopathy. GABA concentrations were low in the CSF of three of five living patients. Mean GABA content was reduced by 30 to 50% in five brain regions (frontal, occipital, and cerebellar cortex, caudate nucleus, and medial dorsal thalamus) in five fatal cases. GABA content was normal in brain regions where GABA is characteristically reduced in Huntington's disease. Choline acetyltransferase activity was diminished (by 25 to 35%) in cerebral cortex of the dialysis encephalopathy patients.

Resting state fMRI entropy probes complexity of brain activity in adults with ADHD.

PubMed

Sokunbi, Moses O; Fung, Wilson; Sawlani, Vijay; Choppin, Sabine; Linden, David E J; Thome, Johannes

2013-12-30

In patients with attention deficit hyperactivity disorder (ADHD), quantitative neuroimaging techniques have revealed abnormalities in various brain regions, including the frontal cortex, striatum, cerebellum, and occipital cortex. Nonlinear signal processing techniques such as sample entropy have been used to probe the regularity of brain magnetoencephalography signals in patients with ADHD. In the present study, we extend this technique to analyse the complex output patterns of the 4 dimensional resting state functional magnetic resonance imaging signals in adult patients with ADHD. After adjusting for the effect of age, we found whole brain entropy differences (P=0.002) between groups and negative correlation (r=-0.45) between symptom scores and mean whole brain entropy values, indicating lower complexity in patients. In the regional analysis, patients showed reduced entropy in frontal and occipital regions bilaterally and a significant negative correlation between the symptom scores and the entropy maps at a family-wise error corrected cluster level of P<0.05 (P=0.001, initial threshold). Our findings support the hypothesis of abnormal frontal-striatal-cerebellar circuits in ADHD and the suggestion that sample entropy is a useful tool in revealing abnormalities in the brain dynamics of patients with psychiatric disorders. © 2013 Elsevier Ireland Ltd. All rights reserved.

Neuroimaging meta-analysis of cannabis use studies reveals convergent functional alterations in brain regions supporting cognitive control and reward processing.

PubMed

Yanes, Julio A; Riedel, Michael C; Ray, Kimberly L; Kirkland, Anna E; Bird, Ryan T; Boeving, Emily R; Reid, Meredith A; Gonzalez, Raul; Robinson, Jennifer L; Laird, Angela R; Sutherland, Matthew T

2018-03-01

Lagging behind rapid changes to state laws, societal views, and medical practice is the scientific investigation of cannabis's impact on the human brain. While several brain imaging studies have contributed important insight into neurobiological alterations linked with cannabis use, our understanding remains limited. Here, we sought to delineate those brain regions that consistently demonstrate functional alterations among cannabis users versus non-users across neuroimaging studies using the activation likelihood estimation meta-analysis framework. In ancillary analyses, we characterized task-related brain networks that co-activate with cannabis-affected regions using data archived in a large neuroimaging repository, and then determined which psychological processes may be disrupted via functional decoding techniques. When considering convergent alterations among users, decreased activation was observed in the anterior cingulate cortex, which co-activated with frontal, parietal, and limbic areas and was linked with cognitive control processes. Similarly, decreased activation was observed in the dorsolateral prefrontal cortex, which co-activated with frontal and occipital areas and linked with attention-related processes. Conversely, increased activation among users was observed in the striatum, which co-activated with frontal, parietal, and other limbic areas and linked with reward processing. These meta-analytic outcomes indicate that cannabis use is linked with differential, region-specific effects across the brain.

Subliminal semantic priming changes the dynamic causal influence between the left frontal and temporal cortex.

PubMed

Matsumoto, Atsushi; Kakigi, Ryusuke

2014-01-01

Recent neuroimaging experiments have revealed that subliminal priming of a target stimulus leads to the reduction of neural activity in specific regions concerned with processing the target. Such findings lead to questions about the degree to which the subliminal priming effect is based only on decreased activity in specific local brain regions, as opposed to the influence of neural mechanisms that regulate communication between brain regions. To address this question, this study recorded EEG during performance of a subliminal semantic priming task. We adopted an information-based approach that used independent component analysis and multivariate autoregressive modeling. Results indicated that subliminal semantic priming caused significant modulation of alpha band activity in the left inferior frontal cortex and modulation of gamma band activity in the left inferior temporal regions. The multivariate autoregressive approach confirmed significant increases in information flow from the inferior frontal cortex to inferior temporal regions in the early time window that was induced by subliminal priming. In the later time window, significant enhancement of bidirectional causal flow between these two regions underlying subliminal priming was observed. Results suggest that unconscious processing of words influences not only local activity of individual brain regions but also the dynamics of neural communication between those regions.

Diurnal alterations of brain electrical activity in healthy adults: a LORETA study.

PubMed

Toth, Marton; Kiss, Attila; Kosztolanyi, Peter; Kondakor, Istvan

2007-01-01

EEG background activity was investigated by low resolution brain electromagnetic tomography (LORETA) to test the diurnal alterations of brain electrical activity in healthy adults. Fourteen right-handed healthy male postgraduate medical students were examined four times (8 a.m., 2 p.m., 8 p.m. and next day 2 p.m.). LORETA was computed to localize generators of EEG frequency components. Comparing the EEG activity between 2 p.m. and 8 a.m., increased activity was seen (1) in theta band (6.5-8 Hz) in the left prefrontal, bilateral mesial frontal and anterior cingulate cortex; (2) in alpha2 band (10.5-12 Hz) in the bilateral precuneus and posterior parietal cortex as well as in the right temporo-occipital cortex; (3) in beta1-2-3 band (12.5-30 Hz) in the right hippocampus and parieto-occipital cortex, left frontal and bilateral cingulate cortex. Comparing the brain activity between 8 p.m. and 8 a.m., (1) midline theta activity disappeared; (2) increased alpha2 band activity was seen in the left hemisphere (including the left hippocampus); and (3) increased beta bands activity was found over almost the whole cortex (including both of hippocampi) with the exception of left temporo-occipital region. There were no significant changes between the background activities of 2 p.m. and next day 2 p.m. Characteristic distribution of increased activity of cortex (no change in delta band, and massive changes in the upper frequency bands) may mirror increasing activation of reticular formation and thus evoked thalamocortical feedback mechanisms as a sign of maintenance of arousal.

Cultural differences in human brain activity: a quantitative meta-analysis.

PubMed

Han, Shihui; Ma, Yina

2014-10-01

Psychologists have been trying to understand differences in cognition and behavior between East Asian and Western cultures within a single cognitive framework such as holistic versus analytic or interdependent versus independent processes. However, it remains unclear whether cultural differences in multiple psychological processes correspond to the same or different neural networks. We conducted a quantitative meta-analysis of 35 functional MRI studies to examine cultural differences in brain activity engaged in social and non-social processes. We showed that social cognitive processes are characterized by stronger activity in the dorsal medial prefrontal cortex, lateral frontal cortex and temporoparietal junction in East Asians but stronger activity in the anterior cingulate, ventral medial prefrontal cortex and bilateral insula in Westerners. Social affective processes are associated with stronger activity in the right dorsal lateral frontal cortex in East Asians but greater activity in the left insula and right temporal pole in Westerners. Non-social processes induce stronger activity in the left inferior parietal cortex, left middle occipital and left superior parietal cortex in East Asians but greater activations in the right lingual gyrus, right inferior parietal cortex and precuneus in Westerners. The results suggest that cultural differences in social and non-social processes are mediated by distinct neural networks. Moreover, East Asian cultures are associated with increased neural activity in the brain regions related to inference of others' mind and emotion regulation whereas Western cultures are associated with enhanced neural activity in the brain areas related to self-relevance encoding and emotional responses during social cognitive/affective processes. Copyright © 2014 Elsevier Inc. All rights reserved.

Conflict detection and resolution rely on a combination of common and distinct cognitive control networks.

PubMed

Li, Qi; Yang, Guochun; Li, Zhenghan; Qi, Yanyan; Cole, Michael W; Liu, Xun

2017-12-01

Cognitive control can be activated by stimulus-stimulus (S-S) and stimulus-response (S-R) conflicts. However, whether cognitive control is domain-general or domain-specific remains unclear. To deepen the understanding of the functional organization of cognitive control networks, we conducted activation likelihood estimation (ALE) from 111 neuroimaging studies to examine brain activation in conflict-related tasks. We observed that fronto-parietal and cingulo-opercular networks were commonly engaged by S-S and S-R conflicts, showing a domain-general pattern. In addition, S-S conflicts specifically activated distinct brain regions to a greater degree. These regions were implicated in the processing of the semantic-relevant attribute, including the inferior frontal cortex (IFC), superior parietal cortex (SPC), superior occipital cortex (SOC), and right anterior cingulate cortex (ACC). By contrast, S-R conflicts specifically activated the left thalamus, middle frontal cortex (MFC), and right SPC, which were associated with detecting response conflict and orienting spatial attention. These findings suggest that conflict detection and resolution involve a combination of domain-general and domain-specific cognitive control mechanisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

Network analysis of brain activations in working memory: behavior and age relationships.

PubMed

Mencl, W E; Pugh, K R; Shaywitz, S E; Shaywitz, B A; Fulbright, R K; Constable, R T; Skudlarski, P; Katz, L; Marchione, K E; Lacadie, C; Gore, J C

2000-10-01

Forty-six middle-aged female subjects were scanned using functional Magnetic Resonance Imaging (fMRI) during performance of three distinct stages of a working memory task-encoding, rehearsal, and recognition-for both printed pseudowords and visual forms. An expanse of areas, involving the inferior frontal, parietal, and extrastriate cortex, was active in response to stimuli during both the encoding and recognition periods. Additional increases during memory recognition were seen in right prefrontal regions, replicating a now-common finding [for reviews, see Fletcher et al. (1997) Trends Neurosci 20:213-218; MacLeod et al. (1998) NeuroImage 7:41-48], and broadly supporting the Hemispheric Encoding/Retrieval Asymmetry hypothesis [Tulving et al. (1994) Proc Natl Acad Sci USA 91:2016-2020]. Notably, this asymmetry was not qualified by the type of material being processed. A few sites demonstrated higher activity levels during the rehearsal period, in the absence of any new stimuli, including the medial extrastriate, precuneus, and the medial temporal lobe. Further analyses examined relationships among subjects' brain activations, age, and behavioral scores on working memory tests, acquired outside the scanner. Correlations between brain scores and behavior scores indicated that activations in a number of areas, mainly frontal, were associated with performance. A multivariate analysis, Partial Least Squares [McIntosh et al. (1996) NeuroImage 3:143-157, (1997) Hum Brain Map 5:323-327], was then used to extract component effects from this large set of univariate correlations. Results indicated that better memory performance outside the scanner was associated with higher activity at specific sites within the frontal and, additionally, the medial temporal lobes. Analysis of age effects revealed that younger subjects tended to activate more than older subjects in areas of extrastriate cortex, medial frontal cortex, and the right medial temporal lobe; older subjects tended to activate more than younger subjects in the insular cortex, right inferior temporal lobe, and right inferior frontal gyrus. These results extend recent reports indicating that these regions are specifically involved in the memory impairments seen with aging. Copyright 2000 Wiley-Liss, Inc.

Structural Brain Changes Following Left Temporal Low-Frequency rTMS in Patients with Subjective Tinnitus

PubMed Central

Langguth, Berthold; Poeppl, Timm B.; Rupprecht, Rainer; Hajak, Göran; Landgrebe, Michael; Schecklmann, Martin

2014-01-01

Repetitive transcranial magnetic stimulation (rTMS) of the temporal cortex has been used to treat patients with subjective tinnitus. While rTMS is known to induce morphological changes in healthy subjects, no study has investigated yet whether rTMS treatment induces grey matter (GM) changes in tinnitus patients as well, whether these changes are correlated with treatment success, and whether GM at baseline is a useful predictor for treatment outcome. Therefore, we examined magnetic resonance images of 77 tinnitus patients who were treated with rTMS of the left temporal cortex (10 days, 2000 stimuli/day, 1 Hz). At baseline and after the last treatment session high-resolution structural images of the brain were acquired and tinnitus severity was assessed. For a subgroup of 41 patients, additional brain scans were done after a follow-up period of 90 days. GM changes were analysed by means of voxel based morphometry. Transient GM decreases were detectable in several brain regions, especially in the insula and the inferior frontal cortex. These changes were not related to treatment outcome though. Baseline images correlated with change in tinnitus severity in the frontal cortex and the lingual gyrus, suggesting that GM at baseline might hold potential as a possible predictor for treatment outcome. PMID:24991438

Unraveling the mechanism of neuroprotection of curcumin in arsenic induced cholinergic dysfunctions in rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Srivastava, Pranay; Yadav, Rajesh S.; Department of Crimnology and Forensic Science, Harisingh Gour University, Sagar 470 003

Earlier, we found that arsenic induced cholinergic deficits in rat brain could be protected by curcumin. In continuation to this, the present study is focused to unravel the molecular mechanisms associated with the protective efficacy of curcumin in arsenic induced cholinergic deficits. Exposure to arsenic (20 mg/kg body weight, p.o) for 28 days in rats resulted to decrease the expression of CHRM2 receptor gene associated with mitochondrial dysfunctions as evident by decrease in the mitochondrial membrane potential, activity of mitochondrial complexes and enhanced apoptosis both in the frontal cortex and hippocampus in comparison to controls. The ultrastructural images of arsenicmore » exposed rats, assessed by transmission electron microscope, exhibited loss of myelin sheath and distorted cristae in the mitochondria both in the frontal cortex and hippocampus as compared to controls. Simultaneous treatment with arsenic (20 mg/kg body weight, p.o) and curcumin (100 mg/kg body weight, p.o) for 28 days in rats was found to protect arsenic induced changes in the mitochondrial membrane potential and activity of mitochondrial complexes both in frontal cortex and hippocampus. Alterations in the expression of pro- and anti-apoptotic proteins and ultrastructural damage in the frontal cortex and hippocampus following arsenic exposure were also protected in rats simultaneously treated with arsenic and curcumin. The data of the present study reveal that curcumin could protect arsenic induced cholinergic deficits by modulating the expression of pro- and anti-apoptotic proteins in the brain. More interestingly, arsenic induced functional and ultrastructural changes in the brain mitochondria were also protected by curcumin. - Highlights: • Neuroprotective mechanism of curcumin in arsenic induced cholinergic deficits studied • Curcumin protected arsenic induced enhanced expression of stress markers in rat brain • Arsenic compromised mitochondrial electron transport chain protected by curcumin • Functional and structural changes in mitochondria by arsenic protected by curcumin.« less

Co-occurring anxiety influences patterns of brain activity in depression.

PubMed

Engels, Anna S; Heller, Wendy; Spielberg, Jeffrey M; Warren, Stacie L; Sutton, Bradley P; Banich, Marie T; Miller, Gregory A

2010-03-01

Brain activation associated with anhedonic depression and co-occurring anxious arousal and anxious apprehension was measured by fMRI during performance of an emotion word Stroop task. Consistent with EEG findings, depression was associated with rightward frontal lateralization in the dorsolateral prefrontal cortex (DLPFC), but only when anxious arousal was elevated and anxious apprehension was low. Activity in the right inferior frontal gyrus (IFG) was also reduced for depression under the same conditions. In contrast, depression was associated with more activity in the anterior cingulate cortex (dorsal ACC and rostral ACC) and the bilateral amygdala. Results imply that depression, particularly when accompanied by anxious arousal, may result in a failure to implement top-down processing by appropriate brain regions (left DLPFC, right IFG) due to increased activation in regions associated with responding to emotionally salient information (right DLPFC, amygdala).

Co-occurring Anxiety Influences Patterns of Brain Activity in Depression

PubMed Central

Engels, Anna S.; Heller, Wendy; Spielberg, Jeffrey M.; Warren, Stacie L.; Sutton, Bradley P.; Banich, Marie T.; Miller, Gregory A.

2011-01-01

Brain activation associated with anhedonic depression and co-occurring anxious arousal and anxious apprehension was measured by fMRI during performance of an emotion-word Stroop task. Consistent with EEG findings, depression was associated with rightward frontal lateralization in dorsolateral prefrontal cortex (DLPFC), but only when anxious arousal was elevated and anxious apprehension was low. Activity in right inferior frontal gyrus (IFG) was also reduced for depression under the same conditions. In contrast, depression was associated with more activity in anterior cingulate cortex (dACC and rACC) and bilateral amygdala. Results imply that depression, particularly when accompanied by anxious arousal, may result in a failure to implement top-down processing by appropriate brain regions (left DLPFC, right IFG) due to increased activation in regions associated with responding to emotionally salient information (right DLPFC, amygdala). PMID:20233962

Frontal white matter damage impairs response inhibition in children following traumatic brain injury.

PubMed

Lipszyc, Jonathan; Levin, Harvey; Hanten, Gerri; Hunter, Jill; Dennis, Maureen; Schachar, Russell

2014-05-01

Inhibition, the ability to suppress inappropriate cognitions or behaviors, can be measured using computer tasks and questionnaires. Inhibition depends on the frontal cortex, but the role of the underlying white matter (WM) is unclear. We assessed the specific impact of frontal WM damage on inhibition in 29 children with moderate-to-severe traumatic brain injury (15 with and 14 without frontal WM damage), 21 children with orthopedic injury, and 29 population controls. We used the Stop Signal Task to measure response inhibition, the Behavior Rating Inventory of Executive Function to assess everyday inhibition, and T2 fluid-attenuated inversion recovery magnetic resonance imaging to identify lesions. Children with frontal WM damage had impaired response inhibition compared with all other groups and poorer everyday inhibition than the orthopedic injury group. Frontal WM lesions most often affected the superior frontal gyrus. These results provide evidence for the critical role of frontal WM in inhibition.

[Functional asymmetry of electric processes in the rabbit brain cortex at formation of the hunger dominant].

PubMed

Rusinova, E V

2011-01-01

The motivational condition of hunger and formation of the hunger dominant after daily food deprivation was studied in the conditions of chronic experiments on rabbits. It was shown, that the hunger condition was accompanied by left sided interhemispher asymmetry on indicators of spectral capacity of EEG frontal and right-hand asymmetry sensorimotor areas of the cortex. A hunger dominant was accompanied by falling of spectral capacity of EEG of areas of both hemispheres. The condition of hunger and a hunger dominant were characterized by right-hand asymmetry on average level of EEG coherence of frontal and sensorimotor areas. At transition of a condition of hunger in a hunger dominant there was an average level of EEG coherence decrease in areas of the right hemisphere. Electric processes of the cortex of the brain at a motivational condition of hunger and a hunger dominant were different.

[Neuroimaging the various symptom dimensions of obsessive-compulsive disorder].

PubMed

Dold, Markus; Aigner, Martin

2009-01-01

Following consensus on fronto-striato-thalamo-frontal dysfunction as the neuronal basis of obsessive-compulsive disorder, and increasing sub-classification of this clinical picture, neurobiological differentiation of the various obsessive symptoms is also attracting interest in neuroimaging research. Original papers studying the neurobiological correlates of the various dimensions of obsessive-compulsive disorder were listed by a systematic literature search. The "washing" factor seems to involve particular brain structures dealing with emotional control (mainly the orbito-frontal cortex (OFC), anterior cingulate cortex (ACC), amygdala and insula), but the predominant areas in the "forbidden thoughts" factor are cognitive control brain regions (mainly basal ganglia and ACC), and in hoarding obsessions and compulsions they are decision-making areas (mainly ventro-medial parts of the OFC and dorso-lateral prefrontal cortex (DLPFC)). The results underline the neurobiological heterogeneity of the obsessive-compulsive disorder clinical picture, pointing the way for future research approaches.

[Processes of logical thought in a case of cerebral vascular lesion].

PubMed

Blanco Men ndez, R; Aguado Balsas, A M

Reasoning and logical thought processes have traditionally been attributed to frontal lobe function or,on the other hand, have been considered as diffuse functions of the brain. However, there is today evidence enough about the possibility to find dissociations in thought processes, depending on logical structure of the experimental tasks and referring to different areas of the brain, frontal and post rolandic ones. To study possible dissociations between thought structures corresponding to categorical and relational logic, on one hand, and propositional logic on the other hand. The case of a brain injured patient with vascular etiology, localized in left frontal parietal cortex, is presented. A specific battery of reasoning tests has been administered. . A differential performance at some reasoning experimental tasks has been found depending on such logical conceptual structures. The possibility of establishing dissociations among certain logical thought and intelectual functions depending on localization of possible brain lesion (frontal versus temporal) is discussed.

Movement preparation and execution: differential functional activation patterns after traumatic brain injury.

PubMed

Gooijers, Jolien; Beets, Iseult A M; Albouy, Genevieve; Beeckmans, Kurt; Michiels, Karla; Sunaert, Stefan; Swinnen, Stephan P

2016-09-01

Years following the insult, patients with traumatic brain injury often experience persistent motor control problems, including bimanual coordination deficits. Previous studies revealed that such deficits are related to brain structural white and grey matter abnormalities. Here, we assessed, for the first time, cerebral functional activation patterns during bimanual movement preparation and performance in patients with traumatic brain injury, using functional magnetic resonance imaging. Eighteen patients with moderate-to-severe traumatic brain injury (10 females; aged 26.3 years, standard deviation = 5.2; age range: 18.4-34.6 years) and 26 healthy young adults (15 females; aged 23.6 years, standard deviation = 3.8; age range: 19.5-33 years) performed a complex bimanual tracking task, divided into a preparation (2 s) and execution (9 s) phase, and executed either in the presence or absence of augmented visual feedback. Performance on the bimanual tracking task, expressed as the average target error, was impaired for patients as compared to controls (P < 0.001) and for trials in the absence as compared to the presence of augmented visual feedback (P < 0.001). At the cerebral level, movement preparation was characterized by reduced neural activation in the patient group relative to the control group in frontal (bilateral superior frontal gyrus, right dorsolateral prefrontal cortex), parietal (left inferior parietal lobe) and occipital (right striate and extrastriate visual cortex) areas (P's < 0.05). During the execution phase, however, the opposite pattern emerged, i.e. traumatic brain injury patients showed enhanced activations compared with controls in frontal (left dorsolateral prefrontal cortex, left lateral anterior prefrontal cortex, and left orbitofrontal cortex), parietal (bilateral inferior parietal lobe, bilateral superior parietal lobe, right precuneus, right primary somatosensory cortex), occipital (right striate and extrastriate visual cortices), and subcortical (left cerebellum crus II) areas (P's < 0.05). Moreover, a significant interaction effect between Feedback Condition and Group in the primary motor area (bilaterally) (P < 0.001), the cerebellum (left) (P < 0.001) and caudate (left) (P < 0.05), revealed that controls showed less overlap of activation patterns accompanying the two feedback conditions than patients with traumatic brain injury (i.e. decreased neural differentiation). In sum, our findings point towards poorer predictive control in traumatic brain injury patients in comparison to controls. Moreover, irrespective of the feedback condition, overactivations were observed in traumatically brain injured patients during movement execution, pointing to more controlled processing of motor task performance. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Spatio-temporal brain dynamics in a combined stimulus-stimulus and stimulus-response conflict task.

PubMed

Frühholz, Sascha; Godde, Ben; Finke, Mareike; Herrmann, Manfred

2011-01-01

It is yet not well known whether different types of conflicts share common or rely on distinct brain mechanisms of conflict processing. We used a combined Flanker (stimulus-stimulus; S-S) and Simon (stimulus-response; S-R) conflict paradigm both in an fMRI and an EEG study. S-S conflicts induced stronger behavioral interference effects compared to S-R conflicts and the latter decayed with increasing response latencies. Besides some similar medial frontal activity across all conflict trials, which was, however, not statically consistent across trials, we especially found distinct activations depending on the type of conflict. S-S conflicts activated the anterior cingulate cortex and modulated the N2 and early P3 component with underlying source activity in inferior frontal cortex. S-R conflicts produced distinct activations in the posterior cingulate cortex and modulated the late P3b component with underlying source activity in superior parietal cortex. Double conflict trials containing both S-S and S-R conflicts revealed, first, distinct anterior frontal activity representing a meta-processing unit and, second, a sequential modulation of the N2 and the P3b component. The N2 modulation during double conflict trials was accompanied by increased source activity in the medial frontal gyrus (MeFG). In summary, S-S and S-R conflict processing mostly rely on distinct mechanisms of conflict processing and these conflicts differentially modulate the temporal stages of stimulus processing. Copyright © 2010 Elsevier Inc. All rights reserved.

Segmentation of the Canine Corpus Callosum using Diffusion Tensor Imaging Tractography

PubMed Central

Pierce, T.T.; Calabrese, E.; White, L.E.; Chen, S.D.; Platt, S.R.; Provenzale, J.M.

2014-01-01

Background We set out to determine functional white matter (WM) connections passing through the canine corpus callosum useful for subsequent studies of canine brains that serve as models for human WM pathway disease. Based on prior studies, we anticipated that the anterior corpus callosum would send projections to the anterior cerebral cortex while progressively posterior segments would send projections to more posterior cortex. Methods A post mortem canine brain was imaged using a 7T MRI producing 100 micron isotropic resolution DTI analyzed by tractography. Using ROIs within cortical locations, which were confirmed by a Nissl stain that identified distinct cortical architecture, we successfully identified 6 important WM pathways. We also compared fractional anisotropy (FA), apparent diffusion coefficient (ADC), radial diffusivity (RD), and axial diffusivity (AD) in tracts passing through the genu and splenium. Results Callosal fibers were organized based upon cortical destination, i.e. fibers from the genu project to the frontal cortex. Histologic results identified the motor cortex based on cytoarchitectonic criteria that allowed placement of ROIs to discriminate between frontal and parietal lobes. We also identified cytoarchitecture typical of the orbital frontal, anterior frontal, and occipital regions and placed ROIs accordingly. FA, ADC, RD and AD values were all higher in posterior corpus callosum fiber tracts. Conclusions Using 6 cortical ROIs, we identified 6 major white matter tracts that reflect major functional divisions of the cerebral hemispheres and we derived quantitative values that can be used for study of canine models of human WM pathological states. PMID:24370161

Altered machinery of protein synthesis is region- and stage-dependent and is associated with α-synuclein oligomers in Parkinson's disease.

PubMed

Garcia-Esparcia, Paula; Hernández-Ortega, Karina; Koneti, Anusha; Gil, Laura; Delgado-Morales, Raul; Castaño, Ester; Carmona, Margarita; Ferrer, Isidre

2015-12-01

Parkinson's disease (PD) is characterized by the accumulation of abnormal α-synuclein in selected regions of the brain following a gradient of severity with disease progression. Whether this is accompanied by globally altered protein synthesis is poorly documented. The present study was carried out in PD stages 1-6 of Braak and middle-aged (MA) individuals without alterations in brain in the substantia nigra, frontal cortex area 8, angular gyrus, precuneus and putamen. Reduced mRNA expression of nucleolar proteins nucleolin (NCL), nucleophosmin (NPM1), nucleoplasmin 3 (NPM3) and upstream binding transcription factor (UBF), decreased NPM1 but not NPM3 nucleolar protein immunostaining in remaining neurons; diminished 18S rRNA, 28S rRNA; reduced expression of several mRNAs encoding ribosomal protein (RP) subunits; and altered protein levels of initiation factor eIF3 and elongation factor eEF2 of protein synthesis was found in the substantia nigra in PD along with disease progression. Although many of these changes can be related to neuron loss in the substantia nigra, selective alteration of certain factors indicates variable degree of vulnerability of mRNAs, rRNAs and proteins in degenerating sustantia nigra. NPM1 mRNA and 18S rRNA was increased in the frontal cortex area 8 at stage 5-6; modifications were less marked and region-dependent in the angular gyrus and precuneus. Several RPs were abnormally regulated in the frontal cortex area 8 and precuneus, but only one RP in the angular gyrus, in PD. Altered levels of eIF3 and eIF1, and decrease eEF1A and eEF2 protein levels were observed in the frontal cortex in PD. No modifications were found in the putamen at any time of the study except transient modifications in 28S rRNA and only one RP mRNA at stages 5-6. These observations further indicate marked region-dependent and stage-dependent alterations in the cerebral cortex in PD. Altered solubility and α-synuclein oligomer formation, assessed in total homogenate fractions blotted with anti-α-synuclein oligomer-specific antibody, was demonstrated in the substantia nigra and frontal cortex, but not in the putamen, in PD. Dramatic increase in α-synuclein oligomers was also seen in fluorescent-activated cell sorter (FACS)-isolated nuclei in the frontal cortex in PD. Altered machinery of protein synthesis is altered in the substantia nigra and cerebral cortex in PD being the frontal cortex area 8 more affected than the angular gyrus and precuneus; in contrast, pathways of protein synthesis are apparently preserved in the putamen. This is associated with the presence of α-synuclein oligomeric species in total homogenates; substantia nigra and frontal cortex are enriched, albeit with different band patterns, in α-synuclein oligomeric species, whereas α-synuclein oligomers are not detected in the putamen.

‘Inner voices’: the cerebral representation of emotional voice cues described in literary texts

PubMed Central

Kreifelts, Benjamin; Gößling-Arnold, Christina; Wertheimer, Jürgen; Wildgruber, Dirk

2014-01-01

While non-verbal affective voice cues are generally recognized as a crucial behavioral guide in any day-to-day conversation their role as a powerful source of information may extend well beyond close-up personal interactions and include other modes of communication such as written discourse or literature as well. Building on the assumption that similarities between the different ‘modes’ of voice cues may not only be limited to their functional role but may also include cerebral mechanisms engaged in the decoding process, the present functional magnetic resonance imaging study aimed at exploring brain responses associated with processing emotional voice signals described in literary texts. Emphasis was placed on evaluating ‘voice’ sensitive as well as task- and emotion-related modulations of brain activation frequently associated with the decoding of acoustic vocal cues. Obtained findings suggest that several similarities emerge with respect to the perception of acoustic voice signals: results identify the superior temporal, lateral and medial frontal cortex as well as the posterior cingulate cortex and cerebellum to contribute to the decoding process, with similarities to acoustic voice perception reflected in a ‘voice’-cue preference of temporal voice areas as well as an emotion-related modulation of the medial frontal cortex and a task-modulated response of the lateral frontal cortex. PMID:24396008

Activation of sensory cortex by imagined genital stimulation: an fMRI analysis

PubMed Central

Wise, Nan J.; Frangos, Eleni; Komisaruk, Barry R.

2016-01-01

Background During the course of a previous study, our laboratory made a serendipitous finding that just thinking about genital stimulation resulted in brain activations that overlapped with, and differed from, those generated by physical genital stimulation. Objective This study extends our previous findings by further characterizing how the brain differentially processes physical ‘touch’ stimulation and ‘imagined’ stimulation. Design Eleven healthy women (age range 29–74) participated in an fMRI study of the brain response to imagined or actual tactile stimulation of the nipple and clitoris. Two additional conditions – imagined dildo self-stimulation and imagined speculum stimulation – were included to characterize the effects of erotic versus non-erotic imagery. Results Imagined and tactile self-stimulation of the nipple and clitoris each activated the paracentral lobule (the genital region of the primary sensory cortex) and the secondary somatosensory cortex. Imagined self-stimulation of the clitoris and nipple resulted in greater activation of the frontal pole and orbital frontal cortex compared to tactile self-stimulation of these two bodily regions. Tactile self-stimulation of the clitoris and nipple activated the cerebellum, primary somatosensory cortex (hand region), and premotor cortex more than the imagined stimulation of these body regions. Imagining dildo stimulation generated extensive brain activation in the genital sensory cortex, secondary somatosensory cortex, hippocampus, amygdala, insula, nucleus accumbens, and medial prefrontal cortex, whereas imagining speculum stimulation generated only minimal activation. Conclusion The present findings provide evidence of the potency of imagined stimulation of the genitals and that the following brain regions may participate in erogenous experience: primary and secondary sensory cortices, sensory-motor integration areas, limbic structures, and components of the ‘reward system’. In addition, these results suggest a mechanism by which some individuals may be able to generate orgasm by imagery in the absence of physical stimulation. PMID:27791966

Reciprocal activation/inactivation of ERK in the amygdala and frontal cortex is correlated with the degree of novelty of an open-field environment.

PubMed

Sanguedo, Frederico Velasco; Dias, Caio Vitor Bueno; Dias, Flavia Regina Cruz; Samuels, Richard Ian; Carey, Robert J; Carrera, Marinete Pinheiro

2016-03-01

Phosphorylated extracellular signal-regulated kinase (ERK) has been used to identify brain areas activated by exogenous stimuli including psychostimulant drugs. Assess the role of the amygdala in emotional responses. Experimental manipulations were performed in which environmental familiarity was the variable. To provide the maximal degree of familiarity, ERK was measured after removal from the home cage and re-placement back into the same cage. To maximize exposure to an unfamiliar environment, ERK was measured following placement into a novel open field. To assess whether familiarity was the critical variable in the ERK response to the novel open field, ERK was also measured after either four or eight placements into the same environment. ERK quantification was carried out in the amygdala, frontal cortex, and the nucleus accumbens. After home cage re-placement, ERK activation was found in the frontal cortex and nucleus accumbens but was absent in the amygdala. Following placement in a novel environment, ERK activation was more prominent in the amygdala than the frontal cortex or nucleus accumbens. In contrast, with habituation to the novel environment, ERK phosphors declined markedly in the amygdala but increased in the frontal cortex and nucleus accumbens to the level observed following home cage re-placement. The differential responsiveness of the amygdala versus the frontal cortex and the nucleus accumbens to a novel versus a habituated environment is consistent with a reciprocal interaction between these neural systems and points to their important role in the mediation of behavioral activation to novelty and behavioral inactivation with habituation.

Inefficiency in Self-organized Attentional Switching in the Normal Aging Population is Associated with Decreased Activity in the Ventrolateral Prefrontal Cortex

PubMed Central

Hampshire, Adam; Gruszka, Aleksandra; Fallon, Sean J.; Owen, Adrian M.

2010-01-01

Studies of the aging brain have demonstrated that areas of the frontal cortex, along with their associated top–down executive control processes, are particularly prone to the neurodegenerative effects of age. Here, we investigate the effects of aging on brain and behavior using a novel task, which allows us to examine separate components of an individual's chosen strategy during routine problem solving. Our findings reveal that, contrary to previous suggestions of a specific decrease in cognitive flexibility, older participants show no increased level of perseveration to either the recently rewarded object or the recently relevant object category. In line with this lack of perseveration, lateral and medial regions of the orbito-frontal cortex, which are associated with inhibitory control and reward processing, appear to be functionally intact. Instead, a general loss of efficient problem-solving strategy is apparent with a concomitant decrease in neural activity in the ventrolateral prefrontal cortex and the posterior parietal cortex. The dorsolateral prefrontal cortex is also affected during problem solving, but age-related decline within this region appears to occur at a later stage. PMID:18345987

Emergency Interventions After Severe Traumatic Brain Injury in Rats: Effect on Neuropathology and Functional Outcome

DTIC Science & Technology

2000-01-01

placed in a stereotaxic frame and a left parietal craniotomy was performed. The dura and bone flap were left in place until immediately before CCI. A...microtransducer) was inserted through a burr hole in the frontal bone into the contralateral (right) frontal cortex at the time of craniotomy ...immediately after injury) or vehicle. A separate sham group (all surgery including craniotomy , but no TBI was also studied. Brain temperature maintained at

Dissociable Changes of Frontal and Parietal Cortices in Inherent Functional Flexibility across the Human Life Span.

PubMed

Yin, Dazhi; Liu, Wenjing; Zeljic, Kristina; Wang, Zhiwei; Lv, Qian; Fan, Mingxia; Cheng, Wenhong; Wang, Zheng

2016-09-28

Extensive evidence suggests that frontoparietal regions can dynamically update their pattern of functional connectivity, supporting cognitive control and adaptive implementation of task demands. However, it is largely unknown whether this flexibly functional reconfiguration is intrinsic and occurs even in the absence of overt tasks. Based on recent advances in dynamics of resting-state functional resonance imaging (fMRI), we propose a probabilistic framework in which dynamic reconfiguration of intrinsic functional connectivity between each brain region and others can be represented as a probability distribution. A complexity measurement (i.e., entropy) was used to quantify functional flexibility, which characterizes heterogeneous connectivity between a particular region and others over time. Following this framework, we identified both functionally flexible and specialized regions over the human life span (112 healthy subjects from 13 to 76 years old). Across brainwide regions, we found regions showing high flexibility mainly in the higher-order association cortex, such as the lateral prefrontal cortex (LPFC), lateral parietal cortex, and lateral temporal lobules. In contrast, visual, auditory, and sensory areas exhibited low flexibility. Furthermore, we observed that flexibility of the right LPFC improved during maturation and reduced due to normal aging, with the opposite occurring for the left lateral parietal cortex. Our findings reveal dissociable changes of frontal and parietal cortices over the life span in terms of inherent functional flexibility. This study not only provides a new framework to quantify the spatiotemporal behavior of spontaneous brain activity, but also sheds light on the organizational principle behind changes in brain function across the human life span. Recent neuroscientific research has demonstrated that the human capability of adaptive task control is primarily the result of the flexible operation of frontal brain networks. However, it remains unclear whether this flexibly functional reconfiguration is intrinsic and occurs in the absence of an overt task. In this study, we propose a probabilistic framework to quantify the functional flexibility of each brain region using resting-state fMRI. We identify regions showing high flexibility mainly in the higher-order association cortex. In contrast, primary and unimodal visual and sensory areas show low flexibility. On the other hand, our findings reveal dissociable changes of frontal and parietal cortices in terms of inherent functional flexibility over the life span. Copyright © 2016 the authors 0270-6474/16/3610060-15$15.00/0.

Systemic administration of WIN 55,212-2 increases norepinephrine release in the rat frontal cortex.

PubMed

Oropeza, V C; Page, M E; Van Bockstaele, E J

2005-06-07

Cannabinoid agonists modulate a variety of behavioral functions by activating cannabinoid receptors that are widely distributed throughout the central nervous system. In the present study, norepinephrine efflux was assessed in the frontal cortex of rats that received a systemic administration of the cannabinoid agonist, WIN 55,212-2. The synthetic cannabinoid agonist dose-dependently increased the release of norepinephrine in this brain region. Pretreatment with the cannabinoid receptor antagonist, SR 141716A, blocked the increase in norepinephrine release. To identify sites of cellular activation, immunocytochemical detection of c-Fos was combined with detection of the catecholamine synthesizing enzyme, tyrosine hydroxylase (TH), in the brainstem nucleus locus coeruleus (LC), a region that is the sole source of norepinephrine to the frontal cortex. Systemic administration of WIN 55,212-2 significantly increased the number of c-Fos immunoreactive cells within TH-containing neurons in the LC compared to vehicle-treated rats. Pretreatment with SR 141716A inhibited the WIN 55,212-2 induced c-Fos expression, while the antagonist alone did not affect c-Fos expression. Taken together, these data indicate that systemically administered cannabinoid agonists stimulate norepinephrine release in the frontal cortex by activating noradrenergic neurons in the coeruleo-frontal cortex pathway. These effects may partially underlie changes in attention, arousal and anxiety observed following exposure to cannabis-based drugs.

Necroptosis Resumes Apoptosis in Hippocampus but Not in Frontal Cortex.

PubMed

Nikseresht, Sara; Khodagholi, Fariba; Dargahi, Leila; Ahmadiani, Abolhassan

2017-12-01

Cell death subsequent to or concurrent with neuroinflammation results in some damages like neuron loss and spatial memory impairment. In this study, we demonstrated the temporal pattern of neuroinflammation, necroptotic, and apoptotic cell deaths in hippocampus and frontal cortex following intracerebroventricular administration of lipopolysaccharide (LPS). We evaluated receptor interacting protein kinase 1 (RIP1), RIP3, and two related metabolic enzymes including glutamate-ammonia ligase (GLUL) and glutamate dehydrogenase (GLUD) as necroptosis factors. Apoptosis pathway, antioxidant status and inflammatory cytokines were also assessed. Based on the probable role of these brain regions in working memory performance, spontaneous alternation was evaluated through the Y-maze apparatus. RIP1, RIP3, and then GLUL and GLUD, as well as apoptosis markers, inflammatory regulators, and antioxidant defense demonstrated different time-dependent patterns in hippocampus and frontal cortex. Interestingly, in hippocampus but not in frontal cortex, necroptosis resumed apoptosis. Our results in behavioral section revealed that neuroinflammation along with apoptosis and necroptosis pathways could lead to reversible short-term memory impairment after LPS injection. In conclusion, it can be suggested that there is a region-specific response of cell deaths regulators activation in hippocampus and frontal cortex. In addition, elucidating the time profile of events in response to neuroinflammation would be of great help in mechanistic studies and understanding of pathways interaction. J. Cell. Biochem. 118: 4628-4638, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Contributions of local speech encoding and functional connectivity to audio-visual speech perception

PubMed Central

Giordano, Bruno L; Ince, Robin A A; Gross, Joachim; Schyns, Philippe G; Panzeri, Stefano; Kayser, Christoph

2017-01-01

Seeing a speaker’s face enhances speech intelligibility in adverse environments. We investigated the underlying network mechanisms by quantifying local speech representations and directed connectivity in MEG data obtained while human participants listened to speech of varying acoustic SNR and visual context. During high acoustic SNR speech encoding by temporally entrained brain activity was strong in temporal and inferior frontal cortex, while during low SNR strong entrainment emerged in premotor and superior frontal cortex. These changes in local encoding were accompanied by changes in directed connectivity along the ventral stream and the auditory-premotor axis. Importantly, the behavioral benefit arising from seeing the speaker’s face was not predicted by changes in local encoding but rather by enhanced functional connectivity between temporal and inferior frontal cortex. Our results demonstrate a role of auditory-frontal interactions in visual speech representations and suggest that functional connectivity along the ventral pathway facilitates speech comprehension in multisensory environments. DOI: http://dx.doi.org/10.7554/eLife.24763.001 PMID:28590903

Effects of swim stress and fluoxetine on 5-HT1A receptor gene expression and monoamine metabolism in the rat brain regions.

PubMed

Shishkina, G T; Kalinina, T S; Dygalo, N N

2012-07-01

Changes in gene expression of the brain serotonin (5-HT) 1A receptors may be important for the development and ameliorating depression, however identification of specific stimuli that activate or reduce the receptor transcriptional activity is far from complete. In the present study, the forced swim test (FST) exposure, the first stress session of which is already sufficient to induce behavioral despair in rats, significantly increased 5-HT1A receptor mRNA levels in the brainstem, frontal cortex, and hippocampus at 24 h. In the brainstem and frontal cortex, the elevation in the receptor gene expression after the second forced swim session was not affected following chronic administration of fluoxetine, while in the cortex, both control and FST values were significantly reduced in fluoxetine-treated rats. In contrast to untreated rats, no increase in hippocampal 5-HT1A receptor mRNA was observed in response to FST in rats chronically treated with fluoxetine. Metabolism of 5-HT (5-HIAA/5-HT) in the brainstem was significantly decreased by fluoxetine and further reduced by swim stress, showing a certain degree of independence of these changes on 5-HT1A receptor gene expression that was increased in this brain region only after the FST, but not after fluoxetine. FST exposure also decreased the brainstem dopamine metabolism, which was unexpectedly positively correlated with 5-HT1A receptor mRNA levels in the frontal cortex. Together, these data suggest that the effects of the forced swim stress as well as fluoxetine involve brain region-dependent alterations in 5-HT1A receptor gene transcription, some of which may be interrelated with concomitant changes in catecholamine metabolism.

Brain Abnormalities in Congenital Fibrosis of the Extraocular Muscles Type 1: A Multimodal MRI Imaging Study.

PubMed

Miao, Wen; Man, Fengyuan; Wu, Shaoqin; Lv, Bin; Wang, Zhenchang; Xian, Junfang; Sabel, Bernhard A; He, Huiguang; Jiao, Yonghong

2015-01-01

To explore the possible brain structural and functional alterations in congenital fibrosis of extraocular muscles type 1 (CFEOM1) patients using multimodal MRI imaging. T1-weighted, diffusion tensor images and functional MRI data were obtained from 9 KIF21A positive patients and 19 age- and gender-matched healthy controls. Voxel based morphometry and tract based spatial statistics were applied to the T1-weighted and diffusion tensor images, respectively. Amplitude of low frequency fluctuations and regional homogeneity were used to process the functional MRI data. We then compared these multimodal characteristics between CFEOM1 patients and healthy controls. Compared with healthy controls, CFEOM1 patients demonstrated increased grey matter volume in bilateral frontal orbital cortex and in the right temporal pole. No diffusion indices changes were detected, indicating unaffected white matter microstructure. In addition, from resting state functional MRI data, trend of amplitude of low-frequency fluctuations increases were noted in the right inferior parietal lobe and in the right frontal cortex, and a trend of ReHo increase (p<0.001 uncorrected) in the left precentral gyrus, left orbital frontal cortex, temporal pole and cingulate gyrus. CFEOM1 patients had structural and functional changes in grey matter, but the white matter was unaffected. These alterations in the brain may be due to the abnormality of extraocular muscles and their innervating nerves. Future studies should consider the possible correlations between brain morphological/functional findings and clinical data, especially pertaining to eye movements, to obtain more precise answers about the role of brain area changes and their functional consequence in CFEOM1.

Working memory load modulation of parieto-frontal connections: evidence from dynamic causal modeling

PubMed Central

Ma, Liangsuo; Steinberg, Joel L.; Hasan, Khader M.; Narayana, Ponnada A.; Kramer, Larry A.; Moeller, F. Gerard

2011-01-01

Previous neuroimaging studies have shown that working memory load has marked effects on regional neural activation. However, the mechanism through which working memory load modulates brain connectivity is still unclear. In this study, this issue was addressed using dynamic causal modeling (DCM) based on functional magnetic resonance imaging (fMRI) data. Eighteen normal healthy subjects were scanned while they performed a working memory task with variable memory load, as parameterized by two levels of memory delay and three levels of digit load (number of digits presented in each visual stimulus). Eight regions of interest, i.e., bilateral middle frontal gyrus (MFG), anterior cingulate cortex (ACC), inferior frontal cortex (IFC), and posterior parietal cortex (PPC), were chosen for DCM analyses. Analysis of the behavioral data during the fMRI scan revealed that accuracy decreased as digit load increased. Bayesian inference on model structure indicated that a bilinear DCM in which memory delay was the driving input to bilateral PPC and in which digit load modulated several parieto-frontal connections was the optimal model. Analysis of model parameters showed that higher digit load enhanced connection from L PPC to L IFC, and lower digit load inhibited connection from R PPC to L ACC. These findings suggest that working memory load modulates brain connectivity in a parieto-frontal network, and may reflect altered neuronal processes, e.g., information processing or error monitoring, with the change in working memory load. PMID:21692148

Brain antibodies in the cortex and blood of people with schizophrenia and controls

PubMed Central

Glass, L J; Sinclair, D; Boerrigter, D; Naude, K; Fung, S J; Brown, D; Catts, V S; Tooney, P; O'Donnell, M; Lenroot, R; Galletly, C; Liu, D; Weickert, T W; Shannon Weickert, C

2017-01-01

The immune system is implicated in the pathogenesis of schizophrenia, with elevated proinflammatory cytokine mRNAs found in the brains of ~40% of individuals with the disorder. However, it is not clear if antibodies (specifically immunoglobulin-γ (IgG)) can be found in the brain of people with schizophrenia and if their abundance relates to brain inflammatory cytokine mRNA levels. Therefore, we investigated the localization and abundance of IgG in the frontal cortex of people with schizophrenia and controls, and the impact of proinflammatory cytokine status on IgG abundance in these groups. Brain IgGs were detected surrounding blood vessels in the human and non-human primate frontal cortex by immunohistochemistry. IgG levels did not differ significantly between schizophrenia cases and controls, or between schizophrenia cases in ‘high’ and ‘low’ proinflammatory cytokine subgroups. Consistent with the existence of IgG in the parenchyma of human brain, mRNA and protein of the IgG transporter (FcGRT) were present in the brain, and did not differ according to diagnosis or inflammatory status. Finally, brain-reactive antibody presence and abundance was investigated in the blood of living people. The plasma of living schizophrenia patients and healthy controls contained antibodies that displayed positive binding to Rhesus macaque cerebellar tissue, and the abundance of these antibodies was significantly lower in patients than controls. These findings suggest that antibodies in the brain and brain-reactive antibodies in the blood are present under normal circumstances. PMID:28786974

Brain antibodies in the cortex and blood of people with schizophrenia and controls.

PubMed

Glass, L J; Sinclair, D; Boerrigter, D; Naude, K; Fung, S J; Brown, D; Catts, V S; Tooney, P; O'Donnell, M; Lenroot, R; Galletly, C; Liu, D; Weickert, T W; Shannon Weickert, C

2017-08-08

The immune system is implicated in the pathogenesis of schizophrenia, with elevated proinflammatory cytokine mRNAs found in the brains of ~40% of individuals with the disorder. However, it is not clear if antibodies (specifically immunoglobulin-γ (IgG)) can be found in the brain of people with schizophrenia and if their abundance relates to brain inflammatory cytokine mRNA levels. Therefore, we investigated the localization and abundance of IgG in the frontal cortex of people with schizophrenia and controls, and the impact of proinflammatory cytokine status on IgG abundance in these groups. Brain IgGs were detected surrounding blood vessels in the human and non-human primate frontal cortex by immunohistochemistry. IgG levels did not differ significantly between schizophrenia cases and controls, or between schizophrenia cases in 'high' and 'low' proinflammatory cytokine subgroups. Consistent with the existence of IgG in the parenchyma of human brain, mRNA and protein of the IgG transporter (FcGRT) were present in the brain, and did not differ according to diagnosis or inflammatory status. Finally, brain-reactive antibody presence and abundance was investigated in the blood of living people. The plasma of living schizophrenia patients and healthy controls contained antibodies that displayed positive binding to Rhesus macaque cerebellar tissue, and the abundance of these antibodies was significantly lower in patients than controls. These findings suggest that antibodies in the brain and brain-reactive antibodies in the blood are present under normal circumstances.

MRI volumetry of prefrontal cortex

NASA Astrophysics Data System (ADS)

Sheline, Yvette I.; Black, Kevin J.; Lin, Daniel Y.; Pimmel, Joseph; Wang, Po; Haller, John W.; Csernansky, John G.; Gado, Mokhtar; Walkup, Ronald K.; Brunsden, Barry S.; Vannier, Michael W.

1995-05-01

Prefrontal cortex volumetry by brain magnetic resonance (MR) is required to estimate changes postulated to occur in certain psychiatric and neurologic disorders. A semiautomated method with quantitative characterization of its performance is sought to reliably distinguish small prefrontal cortex volume changes within individuals and between groups. Stereological methods were tested by a blinded comparison of measurements applied to 3D MR scans obtained using an MPRAGE protocol. Fixed grid stereologic methods were used to estimate prefrontal cortex volumes on a graphic workstation, after the images are scaled from 16 to 8 bits using a histogram method. In addition images were resliced into coronal sections perpendicular to the bicommissural plane. Prefrontal cortex volumes were defined as all sections of the frontal lobe anterior to the anterior commissure. Ventricular volumes were excluded. Stereological measurement yielded high repeatability and precision, and was time efficient for the raters. The coefficient of error was

Activation of the serotonergic system by pedaling exercise changes anterior cingulate cortex activity and improves negative emotion.

PubMed

Ohmatsu, Satoko; Nakano, Hideki; Tominaga, Takanori; Terakawa, Yuzo; Murata, Takaho; Morioka, Shu

2014-08-15

Pedaling exercise (PE) of moderate intensity has been shown to ease anxiety and discomfort; however, little is known of the changes that occur in brain activities and in the serotonergic (5-HT) system after PE. Therefore, this study was conducted for the following reasons: (1) to localize the changes in the brain activities induced by PE using a distributed source localization algorithm, (2) to examine the changes in frontal asymmetry, as used in the Davidson model, with electroencephalography (EEG) activity, and (3) to examine the effect of PE on the 5-HT system. A 32-channel EEG was used to record before and after PE. Profile of Mood States tests indicated that there was a significant decrease in tension-anxiety and a significant increase in vigor after PE. A standardized low-resolution brain electromagnetic tomography analysis showed a significant decrease in brain activities after PE in the alpha-2 band (10-12.5 Hz) in the anterior cingulate cortex (ACC). Moreover, a significant increase in frontal EEG asymmetry was observed after PE in the alpha-1 band (7.5-10 Hz). Urine 5-HT levels significantly increased after PE. Urine 5-HT levels positively correlated with the degree of frontal EEG asymmetry in the alpha-1 band and negatively correlated with brain activity in ACC. Our results suggested that PE activates the 5-HT system and consequently induces increases in frontal EEG asymmetry in the alpha-1 band and reductions of brain activity in the alpha-2 band in the ACC region. Copyright © 2014 Elsevier B.V. All rights reserved.

[The Effects of Chronic Alcoholization on the Expression of Brain-Derived Neurotrophic Factor and Its Receptors in the Brains of Mice Genetically Predisposed to Depressive-Like Behavior].

PubMed

Bazovkina, D V; Kondaurova, E M; Tsybko, A S; Kovetskaya, A I; Ilchibaeva, T V; Naumenko, V S

2017-01-01

Brain-derived neurotropic factor (BDNF) plays an important role in mechanisms of depression. Precursor protein of this factor (proBDNF) can initiate apoptosis in the brain, while the mature form of BDNF is involved in neurogenesis. It is known that chronic alcoholization leads to the activation of apoptotic processes, neurodegeneration, brain injury, and cognitive dysfunction. In this work, we have studied the influence of long-term ethanol exposure on the proBDNF and BDNF protein levels, as well as on the expression of genes that encode these proteins in the brain structures of ASC mice with genetic predisposition to depressive-like behavior and in mice from parental nondepressive CBA strain. It was shown that chronic alcoholization results in a reduction of the BDNF level in the hippocampus and an increase in the amount of TrkB and p75 receptors in the frontal cortex of nondepressive CBA mice. At the same time, the long-term alcoholization of depressive ASC mice results in an increase of the proBDNF level in the frontal cortex and a reduction in the p75 protein level in the hippocampus. It has also been shown that, in depressive ASC mice, proBDNF and BDNF levels are significantly lower in the hippocampus and the frontal cortex compared with nondepressive CBA strain. However, no significant differences in the expression of genes encoding the studied proteins were observed. Thus, changes in the expression patterns of proBDNF, BDNF, and their receptors under the influence of alcoholization in the depressive ASC strain and nondepressive CBA strain mice are different.

Generation of novel motor sequences: the neural correlates of musical improvisation.

PubMed

Berkowitz, Aaron L; Ansari, Daniel

2008-06-01

While some motor behavior is instinctive and stereotyped or learned and re-executed, much action is a spontaneous response to a novel set of environmental conditions. The neural correlates of both pre-learned and cued motor sequences have been previously studied, but novel motor behavior has thus far not been examined through brain imaging. In this paper, we report a study of musical improvisation in trained pianists with functional magnetic resonance imaging (fMRI), using improvisation as a case study of novel action generation. We demonstrate that both rhythmic (temporal) and melodic (ordinal) motor sequence creation modulate activity in a network of brain regions comprised of the dorsal premotor cortex, the rostral cingulate zone of the anterior cingulate cortex, and the inferior frontal gyrus. These findings are consistent with a role for the dorsal premotor cortex in movement coordination, the rostral cingulate zone in voluntary selection, and the inferior frontal gyrus in sequence generation. Thus, the invention of novel motor sequences in musical improvisation recruits a network of brain regions coordinated to generate possible sequences, select among them, and execute the decided-upon sequence.

The Neural Correlates of Desire

PubMed Central

Kawabata, Hideaki; Zeki, Semir

2008-01-01

In an event-related fMRI study, we scanned eighteen normal human subjects while they viewed three categories of pictures (events, objects and persons) which they classified according to desirability (desirable, indifferent or undesirable). Each category produced activity in a distinct part of the visual brain, thus reflecting its functional specialization. We used conjunction analysis to learn whether there is a brain area which is always active when a desirable picture is viewed, regardless of the category to which it belongs. The conjunction analysis of the contrast desirable > undesirable revealed activity in the superior orbito-frontal cortex. This activity bore a positive linear relationship to the declared level of desirability. The conjunction analysis of desirable > indifferent revealed activity in the mid-cingulate cortex and in the anterior cingulate cortex. In the former, activity was greater for desirable and undesirable stimuli than for stimuli classed as indifferent. Other conjunction analyses produced no significant effects. These results show that categorizing any stimulus according to its desirability activates three different brain areas: the superior orbito-frontal, the mid-cingulate, and the anterior cingulate cortices. PMID:18728753

Distinct brain networks for adaptive and stable task control in humans

PubMed Central

Dosenbach, Nico U. F.; Fair, Damien A.; Miezin, Francis M.; Cohen, Alexander L.; Wenger, Kristin K.; Dosenbach, Ronny A. T.; Fox, Michael D.; Snyder, Abraham Z.; Vincent, Justin L.; Raichle, Marcus E.; Schlaggar, Bradley L.; Petersen, Steven E.

2007-01-01

Control regions in the brain are thought to provide signals that configure the brain's moment-to-moment information processing. Previously, we identified regions that carried signals related to task-control initiation, maintenance, and adjustment. Here we characterize the interactions of these regions by applying graph theory to resting state functional connectivity MRI data. In contrast to previous, more unitary models of control, this approach suggests the presence of two distinct task-control networks. A frontoparietal network included the dorsolateral prefrontal cortex and intraparietal sulcus. This network emphasized start-cue and error-related activity and may initiate and adapt control on a trial-by-trial basis. The second network included dorsal anterior cingulate/medial superior frontal cortex, anterior insula/frontal operculum, and anterior prefrontal cortex. Among other signals, these regions showed activity sustained across the entire task epoch, suggesting that this network may control goal-directed behavior through the stable maintenance of task sets. These two independent networks appear to operate on different time scales and affect downstream processing via dissociable mechanisms. PMID:17576922

Increased Cortical Thickness in Male-to-Female Transsexualism.

PubMed

Luders, Eileen; Sánchez, Francisco J; Tosun, Duygu; Shattuck, David W; Gaser, Christian; Vilain, Eric; Toga, Arthur W

2012-08-01

The degree to which one identifies as male or female has a profound impact on one's life. Yet, there is a limited understanding of what contributes to this important characteristic termed gender identity . In order to reveal factors influencing gender identity, studies have focused on people who report strong feelings of being the opposite sex, such as male-to-female (MTF) transsexuals. To investigate potential neuroanatomical variations associated with transsexualism, we compared the regional thickness of the cerebral cortex between 24 MTF transsexuals who had not yet been treated with cross-sex hormones and 24 age-matched control males. Results revealed thicker cortices in MTF transsexuals, both within regions of the left hemisphere (i.e., frontal and orbito-frontal cortex, central sulcus, perisylvian regions, paracentral gyrus) and right hemisphere (i.e., pre-/post-central gyrus, parietal cortex, temporal cortex, precuneus, fusiform, lingual, and orbito-frontal gyrus). These findings provide further evidence that brain anatomy is associated with gender identity, where measures in MTF transsexuals appear to be shifted away from gender-congruent men.

Better without (lateral) frontal cortex? Insight problems solved by frontal patients.

PubMed

Reverberi, Carlo; Toraldo, Alessio; D'Agostini, Serena; Skrap, Miran

2005-12-01

A recently proposed theory on frontal lobe functions claims that the prefrontal cortex, particularly its dorso-lateral aspect, is crucial in defining a set of responses suitable for a particular task, and biasing these for selection. This activity is carried out for virtually any kind of non-routine tasks, without distinction of content. The aim of this study is to test the prediction of Frith's 'sculpting the response space' hypothesis by means of an 'insight' problem-solving task, namely the matchstick arithmetic task. Starting from Knoblich et al.'s interpretation for the failure of healthy controls to solve the matchstick problem, and Frith's theory on the role of dorsolateral frontal cortex, we derived the counterintuitive prediction that patients with focal damage to the lateral frontal cortex should perform better than a group of healthy participants on this rather difficult task. We administered the matchstick task to 35 patients (aged 26-65 years) with a single focal brain lesion as determined by a CT or an MRI scan, and to 23 healthy participants (aged 34-62 years). The findings seemed in line with theoretical predictions. While only 43% of healthy participants could solve the most difficult matchstick problems ('type C'), 82% of lateral frontal patients did so (Fisher's exact test, P < 0.05). In conclusion, the combination of Frith's and Knoblich et al.'s theories was corroborated.

Why Do Some Find it Hard to Disagree? An fMRI Study

PubMed Central

Domínguez D, Juan F.; Taing, Sreyneth A.; Molenberghs, Pascal

2016-01-01

People often find it hard to disagree with others, but how this disposition varies across individuals or how it is influenced by social factors like other people's level of expertise remains little understood. Using functional magnetic resonance imaging (fMRI), we found that activity across a network of brain areas [comprising posterior medial frontal cortex (pMFC), anterior insula (AI), inferior frontal gyrus (IFG), lateral orbitofrontal cortex, and angular gyrus] was modulated by individual differences in the frequency with which participants actively disagreed with statements made by others. Specifically, participants who disagreed less frequently exhibited greater brain activation in these areas when they actually disagreed. Given the role of this network in cognitive dissonance, our results suggest that some participants had more trouble disagreeing due to a heightened cognitive dissonance response. Contrary to expectation, the level of expertise (high or low) had no effect on behavior or brain activity. PMID:26858629

Exploratory Metabolomic Analyses Reveal Compounds Correlated with Lutein Concentration in Frontal Cortex, Hippocampus, and Occipital Cortex of Human Infant Brain

PubMed Central

Lieblein-Boff, Jacqueline C.; Johnson, Elizabeth J.; Kennedy, Adam D.; Lai, Chron-Si; Kuchan, Matthew J.

2015-01-01

Lutein is a dietary carotenoid well known for its role as an antioxidant in the macula, and recent reports implicate a role for lutein in cognitive function. Lutein is the dominant carotenoid in both pediatric and geriatric brain tissue. In addition, cognitive function in older adults correlated with macular and postmortem brain lutein concentrations. Furthermore, lutein was found to preferentially accumulate in the infant brain in comparison to other carotenoids that are predominant in diet. While lutein is consistently related to cognitive function, the mechanisms by which lutein may influence cognition are not clear. In an effort to identify potential mechanisms through which lutein might influence neurodevelopment, an exploratory study relating metabolite signatures and lutein was completed. Post-mortem metabolomic analyses were performed on human infant brain tissues in three regions important for learning and memory: the frontal cortex, hippocampus, and occipital cortex. Metabolomic profiles were compared to lutein concentration, and correlations were identified and reported here. A total of 1276 correlations were carried out across all brain regions. Of 427 metabolites analyzed, 257 were metabolites of known identity. Unidentified metabolite correlations (510) were excluded. In addition, moderate correlations with xenobiotic relationships (2) or those driven by single outliers (3) were excluded from further study. Lutein concentrations correlated with lipid pathway metabolites, energy pathway metabolites, brain osmolytes, amino acid neurotransmitters, and the antioxidant homocarnosine. These correlations were often brain region—specific. Revealing relationships between lutein and metabolic pathways may help identify potential candidates on which to complete further analyses and may shed light on important roles of lutein in the human brain during development. PMID:26317757

Functional grouping and cortical–subcortical interactions in emotion: A meta-analysis of neuroimaging studies

PubMed Central

Kober, Hedy; Barrett, Lisa Feldman; Joseph, Josh; Bliss-Moreau, Eliza; Lindquist, Kristen; Wager, Tor D.

2009-01-01

We performed an updated quantitative meta-analysis of 162 neuroimaging studies of emotion using a novel multi-level kernel-based approach, focusing on locating brain regions consistently activated in emotional tasks and their functional organization into distributed functional groups, independent of semantically defined emotion category labels (e.g., “anger,” “fear”). Such brain-based analyses are critical if our ways of labeling emotions are to be evaluated and revised based on consistency with brain data. Consistent activations were limited to specific cortical sub-regions, including multiple functional areas within medial, orbital, and inferior lateral frontal cortices. Consistent with a wealth of animal literature, multiple subcortical activations were identified, including amygdala, ventral striatum, thalamus, hypothalamus, and periaqueductal gray. We used multivariate parcellation and clustering techniques to identify groups of co-activated brain regions across studies. These analyses identified six distributed functional groups, including medial and lateral frontal groups, two posterior cortical groups, and paralimbic and core limbic/brainstem groups. These functional groups provide information on potential organization of brain regions into large-scale networks. Specific follow-up analyses focused on amygdala, periaqueductal gray (PAG), and hypothalamic (Hy) activations, and identified frontal cortical areas co-activated with these core limbic structures. While multiple areas of frontal cortex co-activated with amygdala sub-regions, a specific region of dorsomedial prefrontal cortex (dmPFC, Brodmann’s Area 9/32) was the only area co-activated with both PAG and Hy. Subsequent mediation analyses were consistent with a pathway from dmPFC through PAG to Hy. These results suggest that medial frontal areas are more closely associated with core limbic activation than their lateral counterparts, and that dmPFC may play a particularly important role in the cognitive generation of emotional states. PMID:18579414

Prenatal stress decreases glycogen synthase kinase-3 phosphorylation in the rat frontal cortex.

PubMed

Szymańska, Magdalena; Suska, Anna; Budziszewska, Bogusława; Jaworska-Feil, Lucylla; Basta-Kaim, Agnieszka; Leśkiewicz, Monika; Kubera, Marta; Gergont, Aleksandra; Kroczka, Sławomir; Kaciński, Marek; Lasoń, Władysław

2009-01-01

It has been postulated that hyperactive glycogen synthase kinase-3 (GSK-3) is an important factor in the pathogenesis of depression, and that this enzyme also contributes to the mechanism of antidepressant drug action. In the present study, we investigated the effect of prenatal stress (an animal model of depression) and long-term treatment with antidepressant drugs on the concentration of GSK-3beta and its main regulating protein kinase B (PKB, Akt). The concentration of GSK-3beta, its inactive form (phospho-Ser9-GSK-3beta), and the amounts of active (phospho-Akt) and total Akt were determined in the hippocampus and frontal cortex in rats. In order to verify our animal model of depression, immobility time in the forced swim test (Porsolt test) was also determined.We found that prenatally stressed rats display a high level of immobility in the Porsolt test and chronic treatment with imipramine, fluoxetine, mirtazapine and tianeptine normalize this change. Western blot analysis demonstrated that GSK-3beta levels were significantly elevated in the frontal cortex, but not in the hippocampus, of prenatally stressed rats. The concentration of its non-active form (phospho-Ser9-GSK-3beta) was decreased only in the former brain structure. No changes were found in the amounts of active (phospho-Akt) and total Akt in both studied brain structures. Chronic treatment with antidepressant drugs diminished stress-induced alterations in GSK-3beta and phospho-GSK-3beta the frontal cortex, but had no effect on the concentration of these enzymes in the hippocampus. Moreover, levels of Akt and phospho-Akt in all experimental groups remained unchanged. Since our animal model of depression is connected with hyperactivity of the HPA axis, our results suggest that GSK-3beta is an important intracellular target for maladaptive glucocorticoid action on frontal cortex neurons and in antidepressant drug effects. Furthermore, the influence of stress and antidepressant drugs on GSK-3beta does not appear to impact the kinase activity of Akt.

Effect of perinatal asphyxia and carbamazepine treatment on cortical dopamine and DOPAC levels.

PubMed

López-Pérez, Silvia J; Morales-Villagrán, Alberto; Medina-Ceja, Laura

2015-02-13

One of the most important manifestations of perinatal asphyxia is the occurrence of seizures, which are treated with antiepileptic drugs, such as carbamazepine. These early seizures, combined with pharmacological treatments, may influence the development of dopaminergic neurotransmission in the frontal cortex. This study aimed to determine the extracellular levels of dopamine and its main metabolite DOPAC in 30-day-old rats that had been asphyxiated for 45 min in a low (8%) oxygen chamber at a perinatal age and treated with daily doses of carbamazepine. Quantifications were performed using microdialysis coupled to a high-performance liquid chromatography (HPLC) system in basal conditions and following the use of the chemical stimulus. Significant decreases in basal and stimulated extracellular dopamine and DOPAC content were observed in the frontal cortex of the asphyxiated group, and these decreases were partially recovered in the animals administered daily doses of carbamazepine. Greater basal dopamine concentrations were also observed as an independent effect of carbamazepine. Perinatal asphyxia plus carbamazepine affects extracellular levels of dopamine and DOPAC in the frontal cortex and stimulated the release of dopamine, which provides evidence for the altered availability of dopamine in cortical brain areas during brain development.

Microglia recapitulate a hematopoietic master regulator network in the aging human frontal cortex

PubMed Central

Wehrspaun, Claudia C.; Haerty, Wilfried; Ponting, Chris P.

2015-01-01

Microglia form the immune system of the brain. Previous studies in cell cultures and animal models suggest altered activation states and cellular senescence in the aged brain. Instead, we analyzed 3 transcriptome data sets from the postmortem frontal cortex of 381 control individuals to show that microglia gene markers assemble into a transcriptional module in a gene coexpression network. These markers predominantly represented M1 and M1/M2b activation phenotypes. Expression of genes in this module generally declines over the adult life span. This decrease was more pronounced in microglia surface receptors for microglia and/or neuron crosstalk than in markers for activation state phenotypes. In addition to these receptors for exogenous signals, microglia are controlled by brain-expressed regulatory factors. We identified a subnetwork of transcription factors, including RUNX1, IRF8, PU.1, and TAL1, which are master regulators (MRs) for the age-dependent microglia module. The causal contributions of these MRs on the microglia module were verified using publicly available ChIP-Seq data. Interactions of these key MRs were preserved in a protein-protein interaction network. Importantly, these MRs appear to be essential for regulating microglia homeostasis in the adult human frontal cortex in addition to their crucial roles in hematopoiesis and myeloid cell-fate decisions during embryogenesis. PMID:26002684

Elevation of D4 dopamine receptor mRNA in postmortem schizophrenic brain.

PubMed

Stefanis, N C; Bresnick, J N; Kerwin, R W; Schofield, W N; McAllister, G

1998-01-01

The D4 dopamine (DA) receptor has been proposed to be a target for the development of a novel antipsychotic drug based on its pharmacological and distribution profile. There is much interest in whether D4 DA receptor levels are altered in schizophrenia, but the lack of an available receptor subtype-specific radioligand made this difficult to quantitate. In this study, we examined whether D4 mRNA levels are altered in different brain regions of schizophrenics compared to controls. Ribonuclease protection assays were carried out on total RNA samples isolated postmortem from frontal cortex and caudate brain regions of schizophrenics and matched controls. 32P-labelled RNA probes to the D4 DA receptor and to the housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase (G3PDH), were hybridised with the RNA samples, digested with ribonucleases to remove unhybridised probe, and separated on 6% sequencing gels. Densitometer analysis on the subsequent autoradiogams was used to calculate the relative optical density of D4 mRNA compared to G3PDH mRNA. Statistical analysis of the data revealed a 3-fold higher level (P<0.011) of D4 mRNA in the frontal cortex of schizophrenics compared to controls. No increase was seen in caudate. D4 receptors could play a role in mediating dopaminergic activity in frontal cortex, an activity which may be malfunctioning in schizophrenia.

Developing a Novel Eye Tracking Paradigm to Assess Mild Traumatic Brain Injury: A Feasibility Study of the Bethesda Eye and Attention Measure (BEAM)

DTIC Science & Technology

2012-10-01

system, which includes the retina, lateral geniculate nucleus, striate cortex, superior colliculus, parietal cortex, frontal eye fields... body penetrating the brain, forces generated from events such as a blast or explosion, or other forces yet to be defined. Consistent with the...and loss of productivity (47-57%; Tanielian & Jaycox, 2008). With advances in modern medicine and neuroimaging, more Service Members and civilians

Attention enhances multi-voxel representation of novel objects in frontal, parietal and visual cortices.

PubMed

Woolgar, Alexandra; Williams, Mark A; Rich, Anina N

2015-04-01

Selective attention is fundamental for human activity, but the details of its neural implementation remain elusive. One influential theory, the adaptive coding hypothesis (Duncan, 2001, An adaptive coding model of neural function in prefrontal cortex, Nature Reviews Neuroscience 2:820-829), proposes that single neurons in certain frontal and parietal regions dynamically adjust their responses to selectively encode relevant information. This selective representation may in turn support selective processing in more specialized brain regions such as the visual cortices. Here, we use multi-voxel decoding of functional magnetic resonance images to demonstrate selective representation of attended--and not distractor--objects in frontal, parietal, and visual cortices. In addition, we highlight a critical role for task demands in determining which brain regions exhibit selective coding. Strikingly, representation of attended objects in frontoparietal cortex was highest under conditions of high perceptual demand, when stimuli were hard to perceive and coding in early visual cortex was weak. Coding in early visual cortex varied as a function of attention and perceptual demand, while coding in higher visual areas was sensitive to the allocation of attention but robust to changes in perceptual difficulty. Consistent with high-profile reports, peripherally presented objects could also be decoded from activity at the occipital pole, a region which corresponds to the fovea. Our results emphasize the flexibility of frontoparietal and visual systems. They support the hypothesis that attention enhances the multi-voxel representation of information in the brain, and suggest that the engagement of this attentional mechanism depends critically on current task demands. Copyright © 2015 Elsevier Inc. All rights reserved.

Fatty acid composition of the postmortem prefrontal cortex of patients with schizophrenia, bipolar disorder, and major depressive disorder.

PubMed

Hamazaki, Kei; Maekawa, Motoko; Toyota, Tomoko; Dean, Brian; Hamazaki, Tomohito; Yoshikawa, Takeo

2015-06-30

Postmortem brain studies have shown abnormal levels of n-3 polyunsaturated fatty acids (PUFAs), especially docosahexaenoic acid, in the frontal cortex (particularly the orbitofrontal cortex) of patients with depression, schizophrenia, or bipolar disorder. However, the results from regions in the frontal cortex other than the orbitofrontal cortex are inconsistent. In this study we investigated whether patients with schizophrenia, bipolar disorder, or major depressive disorder have abnormalities in PUFA levels in the prefrontal cortex [Brodmann area (BA) 8]. In postmortem studies, fatty acids in the phospholipids of the prefrontal cortex (BA8) were evaluated by thin layer chromatography and gas chromatography. Specimens were evaluated for patients with schizophrenia (n=15), bipolar disorder (n=15), or major depressive disorder (n=15) and compared with unaffected controls (n=15). In contrast to previous studies, we found no significant differences in the levels of PUFAs or other fatty acids in the prefrontal cortex (BA8) between patients and controls. Subanalysis by sex also showed no significant differences. No significant differences were found in any individual fatty acids between suicide and non-suicide cases. These psychiatric disorders might be characterized by very specific fatty acid compositions in certain areas of the brain, and BA8 might not be involved in abnormalities of PUFA metabolism. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Toluene effects on oxidative stress in brain regions of young-adult, middle-age, and senescent Brown Norway rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kodavanti, Prasada Rao S., E-mail: kodavanti.prasada@epa.gov; Royland, Joyce E.; Richards, Judy E.

The influence of aging on susceptibility to environmental contaminants is not well understood. To extend knowledge in this area, we examined effects in rat brain of the volatile organic compound, toluene. The objective was to test whether oxidative stress (OS) plays a role in the adverse effects caused by toluene exposure, and if so, if effects are age-dependent. OS parameters were selected to measure the production of reactive oxygen species (NADPH Quinone oxidoreductase 1 (NQO1), NADH Ubiquinone reductase (UBIQ-RD)), antioxidant homeostasis (total antioxidant substances (TAS), superoxide dismutase (SOD), {gamma}-glutamylcysteine synthetase ({gamma}-GCS), glutathione transferase (GST), glutathione peroxidase (GPX), glutathione reductase (GRD)),more » and oxidative damage (total aconitase and protein carbonyls). In this study, Brown Norway rats (4, 12, and 24 months) were dosed orally with toluene (0, 0.65 or 1 g/kg) in corn oil. Four hours later, frontal cortex, cerebellum, striatum, and hippocampus were dissected, quick frozen on dry ice, and stored at - 80 Degree-Sign C until analysis. Some parameters of OS were found to increase with age in select brain regions. Toluene exposure also resulted in increased OS in select brain regions. For example, an increase in NQO1 activity was seen in frontal cortex and cerebellum of 4 and 12 month old rats following toluene exposure, but only in the hippocampus of 24 month old rats. Similarly, age and toluene effects on glutathione enzymes were varied and brain-region specific. Markers of oxidative damage reflected changes in oxidative stress. Total aconitase activity was increased by toluene in frontal cortex and cerebellum at 12 and 24 months, respectively. Protein carbonyls in both brain regions and in all age groups were increased by toluene, but step-down analyses indicated toluene effects were statistically significant only in 12 month old rats. These results indicate changes in OS parameters with age and toluene exposure resulted in oxidative damage in frontal cortex and cerebellum of 12 month old rats. Although increases in oxidative damage are associated with increases in horizontal motor activity in older rats, further research is warranted to determine if these changes in OS parameters are related to neurobehavioral and neurophysiological effects of toluene in animal models of aging.« less

Social isolation stress and chronic glutathione deficiency have a common effect on the glutamine-to-glutamate ratio and myo-inositol concentration in the mouse frontal cortex.

PubMed

Corcoba, Alberto; Gruetter, Rolf; Do, Kim Q; Duarte, João M N

2017-09-01

Environmental stress can interact with genetic predisposition to increase the risk of developing psychopathology. In this work, we tested the hypothesis that social isolation stress interacts with impaired glutathione synthesis and have cumulative effects on the neurochemical profile of the frontal cortex. A mouse model with chronic glutathione deficit induced by knockout (-/-) of the glutamate-cysteine ligase modulatory subunit (Gclm) was exposed to social isolation stress from weaning to post-natal day 65. Using magnetic resonance methods at high-field (14.1 T), we analysed the neurochemical profile in the frontal cortex, brain size and ventricular volume of adult animals. Glutathione deficit was accompanied by elevated concentrations of N-acetylaspartate, alanine, and glutamine, as well as the ratio of glutamine-to-glutamate (Gln/Glu), and by a reduction in levels of myo-inositol and choline-containing compounds in the frontal cortex of -/- animals with respect to wild-type littermates. Although there was no significant interaction between social isolation stress and glutathione deficiency, mice reared in isolation displayed lower myo-inositol concentration (-8.4%, p < 0.05) and larger Gln/Glu (+7.6%, p < 0.05), relative to those in group housing. Furthermore, glutathione deficiency caused a reduction in whole brain volume and enlargement of ventricles, but social isolation had no effect on these parameters. We conclude that social isolation caused neurochemical alterations that may add to those associated to impaired glutathione synthesis. © 2017 International Society for Neurochemistry.

Differential alterations of cortical glutamatergic binding sites in senile dementia of the Alzheimer type

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chalmers, D.T.; Dewar, D.; Graham, D.I.

1990-02-01

Involvement of cortical glutamatergic mechanisms in senile dementia of the Alzheimer type (SDAT) has been investigated with quantitative ligand-binding autoradiography. The distribution and density of Na(+)-dependent glutamate uptake sites and glutamate receptor subtypes--kainate, quisqualate, and N-methyl-D-aspartate--were measured in adjacent sections of frontal cortex obtained postmortem from six patients with SDAT and six age-matched controls. The number of senile plaques was determined in the same brain region. Binding of D-(3H)aspartate to Na(+)-dependent uptake sites was reduced by approximately 40% throughout SDAT frontal cortex relative to controls, indicating a general loss of glutamatergic presynaptic terminals. (3H)Kainate receptor binding was significantly increased bymore » approximately 70% in deep layers of SDAT frontal cortex compared with controls, whereas this binding was unaltered in superficial laminae. There was a positive correlation (r = 0.914) between kainate binding and senile plaque number in deep cortical layers. Quisqualate receptors, as assessed by 2-amino-3-hydroxy-5-(3H)methylisoxazole-4-propionic acid binding, were unaltered in SDAT frontal cortex compared with controls. There was a small reduction (25%) in N-methyl-D-aspartate-sensitive (3H)glutamate binding only in superficial cortical layers of SDAT brains relative to control subjects. (3H)Glutamate binding in SDAT subjects was unrelated to senile plaque number in superficial cortical layers (r = 0.104). These results indicate that in the presence of cortical glutamatergic terminal loss in SDAT plastic alterations occur in some glutamate receptor subtypes but not in others.« less

Segmentation of the canine corpus callosum using diffusion-tensor imaging tractography.

PubMed

Pierce, Theodore T; Calabrese, Evan; White, Leonard E; Chen, Steven D; Platt, Simon R; Provenzale, James M

2014-01-01

We set out to determine functional white matter (WM) connections passing through the canine corpus callosum; these WM connections would be useful for subsequent studies of canine brains that serve as models for human WM pathway disease. Based on prior studies, we anticipated that the anterior corpus callosum would send projections to the anterior cerebral cortex whereas progressively posterior segments would send projections to more posterior cortex. A postmortem canine brain was imaged using a 7-T MRI system producing 100-μm-isotropic-resolution diffusion-tensor imaging analyzed by tractography. Using regions of interest (ROIs) within cortical locations, which were confirmed by a Nissl stain that identified distinct cortical architecture, we successfully identified six important WM pathways. We also compared fractional anisotropy (FA), apparent diffusion coefficient (ADC), radial diffusivity, and axial diffusivity in tracts passing through the genu and splenium. Callosal fibers were organized on the basis of cortical destination (e.g., fibers from the genu project to the frontal cortex). Histologic results identified the motor cortex on the basis of cytoarchitectonic criteria that allowed placement of ROIs to discriminate between frontal and parietal lobes. We also identified cytoarchitecture typical of the orbital frontal, anterior frontal, and occipital regions and placed ROIs accordingly. FA, ADC, radial diffusivity, and axial diffusivity values were all higher in posterior corpus callosum fiber tracts. Using six cortical ROIs, we identified six major WM tracts that reflect major functional divisions of the cerebral hemispheres, and we derived quantitative values that can be used for study of canine models of human WM pathologic states.

Vertex- and atlas-based comparisons in measures of cortical thickness, gyrification and white matter volume between humans and chimpanzees.

PubMed

Hopkins, William D; Li, Xiang; Crow, Tim; Roberts, Neil

2017-01-01

What changes in cortical organisation characterise global and localised variation between humans and chimpanzees remains a topic of considerable interest in evolutionary neuroscience. Here, we examined regional variation in cortical thickness, gyrification and white matter in samples of human and chimpanzee brains. Both species were MRI scanned on the same platform using identical procedures. The images were processed and segmented by FSL and FreeSurfer and the relative changes in cortical thickness, gyrification and white matter across the entire cortex were compared between species. In general, relative to chimpanzees, humans had significantly greater gyrification and significantly thinner cortex, particularly in the frontal lobe. Human brains also had disproportionately higher white matter volumes in the frontal lobe, particularly in prefrontal regions. Collectively, the findings suggest that after the split from the common ancestor, white matter expansion and subsequently increasing gyrification occurred in the frontal lobe possibly due to increased selection for human cognitive and motor specialisations.

Neural Mechanism of Inferring Person's Inner Attitude towards Another Person through Observing the Facial Affect in an Emotional Context.

PubMed

Kim, Ji-Woong; Kim, Jae-Jin; Jeong, Bumseok; Kim, Sung-Eun; Ki, Seon Wan

2010-03-01

The goal of the present study was to identify the brain mechanism involved in the attribution of person's attitude toward another person, using facial affective pictures and pictures displaying an affectively-loaded situation. Twenty four right-handed healthy subjects volunteered for our study. We used functional magnetic resonance imaging (MRI) to examine brain activation during attitude attribution task as compared to gender matching tasks. We identified activation in the left inferior frontal cortex, left superior temporal sulcus, and left inferior parietal lobule during the attitude attribution task, compared to the gender matching task. This study suggests that mirror neuron system and ventrolateral inferior frontal cortex play a critical role in the attribution of a person's inner attitude towards another person in an emotional situation.

Cortical and Subcortical Brain Morphometry Differences Between Patients With Autism Spectrum Disorder and Healthy Individuals Across the Lifespan: Results From the ENIGMA ASD Working Group.

PubMed

van Rooij, Daan; Anagnostou, Evdokia; Arango, Celso; Auzias, Guillaume; Behrmann, Marlene; Busatto, Geraldo F; Calderoni, Sara; Daly, Eileen; Deruelle, Christine; Di Martino, Adriana; Dinstein, Ilan; Duran, Fabio Luis Souza; Durston, Sarah; Ecker, Christine; Fair, Damien; Fedor, Jennifer; Fitzgerald, Jackie; Freitag, Christine M; Gallagher, Louise; Gori, Ilaria; Haar, Shlomi; Hoekstra, Liesbeth; Jahanshad, Neda; Jalbrzikowski, Maria; Janssen, Joost; Lerch, Jason; Luna, Beatriz; Martinho, Mauricio Moller; McGrath, Jane; Muratori, Filippo; Murphy, Clodagh M; Murphy, Declan G M; O'Hearn, Kirsten; Oranje, Bob; Parellada, Mara; Retico, Alessandra; Rosa, Pedro; Rubia, Katya; Shook, Devon; Taylor, Margot; Thompson, Paul M; Tosetti, Michela; Wallace, Gregory L; Zhou, Fengfeng; Buitelaar, Jan K

2018-04-01

Neuroimaging studies show structural differences in both cortical and subcortical brain regions in children and adults with autism spectrum disorder (ASD) compared with healthy subjects. Findings are inconsistent, however, and it is unclear how differences develop across the lifespan. The authors investigated brain morphometry differences between individuals with ASD and healthy subjects, cross-sectionally across the lifespan, in a large multinational sample from the Enhancing Neuroimaging Genetics Through Meta-Analysis (ENIGMA) ASD working group. The sample comprised 1,571 patients with ASD and 1,651 healthy control subjects (age range, 2-64 years) from 49 participating sites. MRI scans were preprocessed at individual sites with a harmonized protocol based on a validated automated-segmentation software program. Mega-analyses were used to test for case-control differences in subcortical volumes, cortical thickness, and surface area. Development of brain morphometry over the lifespan was modeled using a fractional polynomial approach. The case-control mega-analysis demonstrated that ASD was associated with smaller subcortical volumes of the pallidum, putamen, amygdala, and nucleus accumbens (effect sizes [Cohen's d], 0.13 to -0.13), as well as increased cortical thickness in the frontal cortex and decreased thickness in the temporal cortex (effect sizes, -0.21 to 0.20). Analyses of age effects indicate that the development of cortical thickness is altered in ASD, with the largest differences occurring around adolescence. No age-by-ASD interactions were observed in the subcortical partitions. The ENIGMA ASD working group provides the largest study of brain morphometry differences in ASD to date, using a well-established, validated, publicly available analysis pipeline. ASD patients showed altered morphometry in the cognitive and affective parts of the striatum, frontal cortex, and temporal cortex. Complex developmental trajectories were observed for the different regions, with a developmental peak around adolescence. These findings suggest an interplay in the abnormal development of the striatal, frontal, and temporal regions in ASD across the lifespan.

Age-and Brain Region-Specific Differences in Mitochondrial Bioenergetics in Brown Norway Rats

EPA Science Inventory

Mitochondria are central regulators of energy homeostasis and play a pivotal role in mechanisms of cellular senescence. The objective of the present study was to evaluate mitochondrial bio­-energetic parameters in five brain regions [brainstem (BS), frontal cortex (FC), cerebellu...

Functional roles of the cingulo-frontal network in performance on working memory.

PubMed

Kondo, Hirohito; Morishita, Masanao; Osaka, Naoyuki; Osaka, Mariko; Fukuyama, Hidenao; Shibasaki, Hiroshi

2004-01-01

We examined the relationship between brain activities and task performance on working memory. A large-scale study was initially administered to identify good and poor performers using the operation span and reading span tasks. On the basis of those span scores, we divided 20 consenting participants into high- and low-span groups. In an fMRI study, the participants performed verification of arithmetic problems and retention of target words either concurrently or separately. The behavioral results showed that performance was better in the high-span group than in the low-span group under a dual-task condition, but not under two single-task conditions. The anterior cingulate cortex (ACC), left prefrontal cortex (PFC), left inferior frontal cortex, and bilateral parietal cortex were primarily activated for both span groups. We found that signal changes in the ACC were greater in the high-span group than in the low-span group under the dual-task condition, but not under the single-task conditions. Structural equation modeling indicated that an estimate of effective connectivity from the ACC to the left PFC was positive for the high-span group and negative for the-low span group, suggesting that closer cooperation between the two brain regions was strongly related to working memory performance. We conclude that central executive functioning for attention shifting is modulated by the cingulo-frontal network.

Ethylene glycol ethers induce apoptosis and disturb glucose metabolism in the rat brain.

PubMed

Pomierny, Bartosz; Krzyżanowska, Weronika; Niedzielska, Ewa; Broniowska, Żaneta; Budziszewska, Bogusława

2016-02-01

Ethylene glycol ethers (EGEs) are compounds widely used in industry and household products, but their potential, adverse effect on brain is poorly understood, so far. The aim of the present study was to determine whether 4-week administration of 2-buthoxyethanol (BE), 2-phenoxyethanol (PHE), and 2-ethoxyethanol (EE) induces apoptotic process in the rat hippocampus and frontal cortex, and whether their adverse effect on the brain cells can result from disturbances in the glucose metabolism. Experiments were conducted on 40 rats, exposed to BE, PHE, EE, saline or sunflower oil for 4 weeks. Markers of apoptosis and glucose metabolism were determined in frontal cortex and hippocampus by western blot, ELISA, and fluorescent-based assays. BE and PHE, but not EE, increased expression of the active form of caspase-3 in the examined brain regions. BE and PHE increased caspase-9 level in the cortex and PHE also in the hippocampus. BE and PHE increased the level of pro-apoptotic proteins (Bax, Bak) and/or reduced the concentration of anti-apoptotic proteins (Bcl-2, Bcl-xL); whereas, the effect of BE was observed mainly in the cortex and that of PHE in the hippocampus. It has also been found that PHE increased brain glucose level, and both BE and PHE elevated pyruvate and lactate concentration. It can be concluded that chronic treatment with BE and PHE induced mitochondrial pathway of apoptosis, and disturbed glucose metabolism in the rat brain. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

How acute total sleep loss affects the attending brain: a meta-analysis of neuroimaging studies.

PubMed

Ma, Ning; Dinges, David F; Basner, Mathias; Rao, Hengyi

2015-02-01

Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. © 2015 Associated Professional Sleep Societies, LLC.

Switch-Independent Task Representations in Frontal and Parietal Cortex.

PubMed

Loose, Lasse S; Wisniewski, David; Rusconi, Marco; Goschke, Thomas; Haynes, John-Dylan

2017-08-16

Alternating between two tasks is effortful and impairs performance. Previous fMRI studies have found increased activity in frontoparietal cortex when task switching is required. One possibility is that the additional control demands for switch trials are met by strengthening task representations in the human brain. Alternatively, on switch trials, the residual representation of the previous task might impede the buildup of a neural task representation. This would predict weaker task representations on switch trials, thus also explaining the performance costs. To test this, male and female participants were cued to perform one of two similar tasks, with the task being repeated or switched between successive trials. Multivoxel pattern analysis was used to test which regions encode the tasks and whether this encoding differs between switch and repeat trials. As expected, we found information about task representations in frontal and parietal cortex, but there was no difference in the decoding accuracy of task-related information between switch and repeat trials. Using cross-classification, we found that the frontoparietal cortex encodes tasks using a generalizable spatial pattern in switch and repeat trials. Therefore, task representations in frontal and parietal cortex are largely switch independent. We found no evidence that neural information about task representations in these regions can explain behavioral costs usually associated with task switching. SIGNIFICANCE STATEMENT Alternating between two tasks is effortful and slows down performance. One possible explanation is that the representations in the human brain need time to build up and are thus weaker on switch trials, explaining performance costs. Alternatively, task representations might even be enhanced to overcome the previous task. Here, we used a combination of fMRI and a brain classifier to test whether the additional control demands under switching conditions lead to an increased or decreased strength of task representations in frontoparietal brain regions. We found that task representations are not modulated significantly by switching processes and generalize across switching conditions. Therefore, task representations in the human brain cannot account for the performance costs associated with alternating between tasks. Copyright © 2017 the authors 0270-6474/17/378033-10$15.00/0.

Functional network centrality in obesity: A resting-state and task fMRI study.

PubMed

García-García, Isabel; Jurado, María Ángeles; Garolera, Maite; Marqués-Iturria, Idoia; Horstmann, Annette; Segura, Bàrbara; Pueyo, Roser; Sender-Palacios, María José; Vernet-Vernet, Maria; Villringer, Arno; Junqué, Carme; Margulies, Daniel S; Neumann, Jane

2015-09-30

Obesity is associated with structural and functional alterations in brain areas that are often functionally distinct and anatomically distant. This suggests that obesity is associated with differences in functional connectivity of regions distributed across the brain. However, studies addressing whole brain functional connectivity in obesity remain scarce. Here, we compared voxel-wise degree centrality and eigenvector centrality between participants with obesity (n=20) and normal-weight controls (n=21). We analyzed resting state and task-related fMRI data acquired from the same individuals. Relative to normal-weight controls, participants with obesity exhibited reduced degree centrality in the right middle frontal gyrus in the resting-state condition. During the task fMRI condition, obese participants exhibited less degree centrality in the left middle frontal gyrus and the lateral occipital cortex along with reduced eigenvector centrality in the lateral occipital cortex and occipital pole. Our results highlight the central role of the middle frontal gyrus in the pathophysiology of obesity, a structure involved in several brain circuits signaling attention, executive functions and motor functions. Additionally, our analysis suggests the existence of task-dependent reduced centrality in occipital areas; regions with a role in perceptual processes and that are profoundly modulated by attention. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Localized cortical chronic traumatic encephalopathy pathology after single, severe axonal injury in human brain.

PubMed

Shively, Sharon B; Edgerton, Sarah L; Iacono, Diego; Purohit, Dushyant P; Qu, Bao-Xi; Haroutunian, Vahram; Davis, Kenneth L; Diaz-Arrastia, Ramon; Perl, Daniel P

2017-03-01

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with repetitive mild impact traumatic brain injury from contact sports. Recently, a consensus panel defined the pathognomonic lesion for CTE as accumulations of abnormally hyperphosphorylated tau (p-tau) in neurons (neurofibrillary tangles), astrocytes and cell processes distributed around small blood vessels at sulcal depths in irregular patterns within the cortex. The pathophysiological mechanism for this lesion is unknown. Moreover, a subset of CTE cases harbors cortical β-amyloid plaques. In this study, we analyzed postmortem brain tissues from five institutionalized patients with schizophrenia and history of surgical leucotomy with subsequent survival of at least another 40 years. Because leucotomy involves severing axons bilaterally in prefrontal cortex, this surgical procedure represents a human model of single traumatic brain injury with severe axonal damage and no external impact. We examined cortical tissues at the leucotomy site and at both prefrontal cortex rostral and frontal cortex caudal to the leucotomy site. For comparison, we analyzed brain tissues at equivalent neuroanatomical sites from non-leucotomized patients with schizophrenia, matched in age and gender. All five leucotomy cases revealed severe white matter damage with dense astrogliosis at the axotomy site and also neurofibrillary tangles and p-tau immunoreactive neurites in the overlying gray matter. Four cases displayed p-tau immunoreactivity in neurons, astrocytes and cell processes encompassing blood vessels at cortical sulcal depths in irregular patterns, similar to CTE. The three cases with apolipoprotein E ε4 haplotype showed scattered β-amyloid plaques in the overlying gray matter, but not the two cases with apolipoprotein E ε3/3 genotype. Brain tissue samples from prefrontal cortex rostral and frontal cortex caudal to the leucotomy site, and all cortical samples from the non-leucotomized patients, showed minimal p-tau and β-amyloid pathology. These findings suggest that chronic axonal damage contributes to the unique pathology of CTE over time.

5-HT has contrasting effects in the frontal cortex, but not the hypothalamus, on changes in noradrenaline efflux induced by the monoamine releasing-agent, d-amphetamine, and the reuptake inhibitor, BTS 54 354.

PubMed

Géranton, Sandrine M; Heal, David J; Stanford, S Clare

2004-03-01

There is extensive evidence for functional interactions between central noradrenergic and serotonergic neurones. Here, dual-probe microdialysis was used in freely-moving rats to compare the effects of 5-HT on noradrenergic transmission in the rat frontal cortex and hypothalamus. We studied the effects of the 5-HT synthesis inhibitor, para-chlorophenylalanine (pCPA; which depleted 5-HT stores in both the frontal cortex and the hypothalamus), on spontaneous efflux of noradrenaline and on the noradrenergic responses to d-amphetamine, and the monoamine reuptake inhibitor, BTS 54 354. pCPA pretreatment alone did not affect spontaneous noradrenaline efflux in either brain region, whether or not alpha2-autoreceptors were inactivated by administration of the alpha2-antagonist, atipamezole (1 mg/kg i.p). However, in the frontal cortex, pCPA pretreatment augmented the amplitude of, and prolonged, the noradrenergic response to local infusion of d-amphetamine (10 microM). In contrast, pCPA abolished the increase in cortical noradrenaline efflux induced by local infusion of BTS 54 354 (50 microM). In the hypothalamus, pCPA did not affect the amplitude of the response to either of these agents but did prolong the effects of d-amphetamine on noradrenaline efflux. These findings suggest that serotonergic transmission has complex effects on the noradrenergic response to drugs that increase noradrenergic transmission in the frontal cortex, but has less influence in the hypothalamus.

Cortical NMDA receptor expression in human chronic alcoholism: influence of the TaqIA allele of ANKK1.

PubMed

Ridge, Justin P; Dodd, Peter R

2009-10-01

Real-time RT-PCR normalized to GAPDH was used to assay N-methyl-D-aspartate (NMDA) receptor NR1, NR2A and NR2B subunit mRNA in human autopsy cortex tissue from chronic alcoholics with and without comorbid cirrhosis of the liver and matched controls. Subunit expression was influenced by the subject's genotype. The TaqIA polymorphism selectively modulated NMDA receptor mean transcript expression in cirrhotic-alcoholic superior frontal cortex, in diametrically opposite ways in male and female subjects. Genetic make-up may differentially influence vulnerability to brain damage by altering the excitation: inhibition balance, particularly in alcoholics with comorbid cirrhosis of the liver. The TaqIA polymorphism occurs within the poorly characterised ankyrin-repeat containing kinase 1 (ANKK1) gene. Using PCR, ANKK1 mRNA transcript was detected in inferior temporal, occipital, superior frontal and primary motor cortex of control human brain. ANKK1 expression may mediate the influence of the TaqIA polymorphism on phenotype.

Brain Abnormalities in Congenital Fibrosis of the Extraocular Muscles Type 1: A Multimodal MRI Imaging Study

PubMed Central

Wu, Shaoqin; Lv, Bin; Wang, Zhenchang; Xian, Junfang; Sabel, Bernhard A.; He, Huiguang; Jiao, Yonghong

2015-01-01

Purpose To explore the possible brain structural and functional alterations in congenital fibrosis of extraocular muscles type 1 (CFEOM1) patients using multimodal MRI imaging. Methods T1-weighted, diffusion tensor images and functional MRI data were obtained from 9 KIF21A positive patients and 19 age- and gender- matched healthy controls. Voxel based morphometry and tract based spatial statistics were applied to the T1-weighted and diffusion tensor images, respectively. Amplitude of low frequency fluctuations and regional homogeneity were used to process the functional MRI data. We then compared these multimodal characteristics between CFEOM1 patients and healthy controls. Results Compared with healthy controls, CFEOM1 patients demonstrated increased grey matter volume in bilateral frontal orbital cortex and in the right temporal pole. No diffusion indices changes were detected, indicating unaffected white matter microstructure. In addition, from resting state functional MRI data, trend of amplitude of low-frequency fluctuations increases were noted in the right inferior parietal lobe and in the right frontal cortex, and a trend of ReHo increase (p<0.001 uncorrected) in the left precentral gyrus, left orbital frontal cortex, temporal pole and cingulate gyrus. Conclusions CFEOM1 patients had structural and functional changes in grey matter, but the white matter was unaffected. These alterations in the brain may be due to the abnormality of extraocular muscles and their innervating nerves. Future studies should consider the possible correlations between brain morphological/functional findings and clinical data, especially pertaining to eye movements, to obtain more precise answers about the role of brain area changes and their functional consequence in CFEOM1. PMID:26186732

High prevalence of brain pathology in violent prisoners: a qualitative CT and MRI scan study.

PubMed

Schiltz, Kolja; Witzel, Joachim G; Bausch-Hölterhoff, Josef; Bogerts, Bernhard

2013-10-01

The aim of this study was to determine the frequency and extent of brain anomalies in a large sample of incarcerated violent offenders not previously considered neuropsychiatrically ill, in comparison with non-violent offenders and non-offending controls. MRI and CT brain scans from 287 male prison inmates (162 violent and 125 non-violent) not diagnosed as mentally ill before that were obtained due to headache, vertigo or psychological complaints during imprisonment were assessed and compared to 52 non-criminal controls. Brain scans were rated qualitatively with respect to evidence of structural brain damage. Each case received a semiquantitative rating of "normal" (=0), "questionably abnormal" (=1) or "definitely abnormal" (=2) for the lateral ventricles, frontal/parietal cortex and medial temporal structures bilaterally as well as third ventricle. Overall, offenders displayed a significantly higher rate of morphological abnormality, with the violent offenders scoring significantly higher than non-violent offenders and controls. This difference was statistically detectable for frontal/parietal cortex, medial temporal structures, third ventricle and the left but not the right lateral ventricle. The remarkable prevalence of brain pathology in convicted violent prisoners detectable by neuroradiological routine assessment not only highlights the importance of frontal and temporal structures in the control of social, and specifically of violent behaviour, but also raises questions on the legal culpability of violent offenders with brain abnormalities. The high proportion of undetected presence of structural brain damage emphasizes the need that in violent criminals, the comprehensive routine neuropsychiatric assessment usually performed in routine forensic psychiatric expertises should be complemented with brain imaging.

Modulation of oxidative stress, inflammation, autophagy and expression of Nrf2 in hippocampus and frontal cortex of rats fed with açaí-enriched diets.

PubMed

Poulose, Shibu M; Bielinski, Donna F; Carey, Amanda; Schauss, Alexander G; Shukitt-Hale, Barbara

2017-06-01

Açaí (Euterpe spp.), an exotic palm fruit, has recently emerged as a promising source of natural antioxidants with wide pharmacological and nutritional value. In this study, two different species of açaí pulp extracts, naturally grown in two distinct regions of the Amazon, namely, Euterpe oleracea Mart. (habitat: Brazilian floodplains of the Amazon) and Euterpe precatoria Mart. (habitat: Bolivian Amazon), were studied for their effects on brain health and cognition. Neurochemical analyses were performed in critical brain regions associated with memory and cognition of 19-month-old açaí-fed rats, in whom the cognitive benefits of açaí had been established. Results indicated significant reductions (P< 0.05) in prooxidant NADPH-oxidoreductase-2 (NOX2) and proinflammatory transcription factor NF-κB in açaí-fed rats. Measurement of Nrf2 expression, a transcription factor for antioxidant enzymes, and a possible link between oxidative stress, neuroinflammation and autophagy mechanisms, indicated significant overexpression (P<0.005) in the hippocampus and frontal cortex of the açaí-fed rats. Furthermore, significant activation of endogenous antioxidant enzymes GST and SOD were also observed in the açaí-fed animals when compared to control. Analysis of autophagy markers such as p62, phospho-mTOR, beclin1 and MAP1B-LC3 revealed differential expression in frontal cortex and hippocampus, mostly indicating an upregulation in the açaí-fed rats. In general, results were more profound for EP than EO in hippocampus as well as frontal cortex. Therefore, an açaí-enriched diet could possibly modulate Nrf2, which is known to modulate the intracellular redox status, thereby regulating the ubiquitin-proteosomal pathway, ultimately affecting cognitive function in the aging brain.

Neurochemical differences in learning and memory paradigms among rats supplemented with anthocyanin-rich blueberry diets and exposed to acute doses of 56Fe particles.

PubMed

Poulose, Shibu M; Rabin, Bernard M; Bielinski, Donna F; Kelly, Megan E; Miller, Marshall G; Thanthaeng, Nopporn; Shukitt-Hale, Barbara

2017-02-01

The protective effects of anthocyanin-rich blueberries (BB) on brain health are well documented and are particularly important under conditions of high oxidative stress, which can lead to "accelerated aging." One such scenario is exposure to space radiation, consisting of high-energy and -charge particles (HZE), which are known to cause cognitive dysfunction and deleterious neurochemical alterations. We recently tested the behavioral and neurochemical effects of acute exposure to HZE particles such as 56 Fe, within 24-48h after exposure, and found that radiation primarily affects memory and not learning. Importantly, we observed that specific brain regions failed to upregulate antioxidant and anti-inflammatory mechanisms in response to this insult. To further examine these endogenous response mechanisms, we have supplemented young rats with diets rich in BB, which are known to contain high amounts of antioxidant-phytochemicals, prior to irradiation. Exposure to 56 Fe caused significant neurochemical changes in hippocampus and frontal cortex, the two critical regions of the brain involved in cognitive function. BB supplementation significantly attenuated protein carbonylation, which was significantly increased by exposure to 56 Fe in the hippocampus and frontal cortex. Moreover, BB supplementation significantly reduced radiation-induced elevations in NADPH-oxidoreductase-2 (NOX2) and cyclooxygenase-2 (COX-2), and upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) in the hippocampus and frontal cortex. Overall results indicate that 56 Fe particles may induce their toxic effects on hippocampus and frontal cortex by reactive oxygen species (ROS) overload, which can cause alterations in the neuronal environment, eventually leading to hippocampal neuronal death and subsequent impairment of cognitive function. Blueberry supplementation provides an effective preventative measure to reduce the ROS load on the CNS in an event of acute HZE exposure. Published by Elsevier Ltd.

Development of the Teenage Brain

ERIC Educational Resources Information Center

Choudhury, Suparna; Charman, Tony; Blakemore, Sarah-Jayne

2008-01-01

Adolescence is a time characterized by change--hormonally, physically, and mentally. We now know that some brain areas, particularly the frontal cortex, continue to develop well beyond childhood. There are two main changes with puberty. First, there is an increase in axonal myelination, which increases transmission speed. Second, there is a…

How Acute Total Sleep Loss Affects the Attending Brain: A Meta-Analysis of Neuroimaging Studies

PubMed Central

Ma, Ning; Dinges, David F.; Basner, Mathias; Rao, Hengyi

2015-01-01

Study Objectives: Attention is a cognitive domain that can be severely affected by sleep deprivation. Previous neuroimaging studies have used different attention paradigms and reported both increased and reduced brain activation after sleep deprivation. However, due to large variability in sleep deprivation protocols, task paradigms, experimental designs, characteristics of subject populations, and imaging techniques, there is no consensus regarding the effects of sleep loss on the attending brain. The aim of this meta-analysis was to identify brain activations that are commonly altered by acute total sleep deprivation across different attention tasks. Design: Coordinate-based meta-analysis of neuroimaging studies of performance on attention tasks during experimental sleep deprivation. Methods: The current version of the activation likelihood estimation (ALE) approach was used for meta-analysis. The authors searched published articles and identified 11 sleep deprivation neuroimaging studies using different attention tasks with a total of 185 participants, equaling 81 foci for ALE analysis. Results: The meta-analysis revealed significantly reduced brain activation in multiple regions following sleep deprivation compared to rested wakefulness, including bilateral intraparietal sulcus, bilateral insula, right prefrontal cortex, medial frontal cortex, and right parahippocampal gyrus. Increased activation was found only in bilateral thalamus after sleep deprivation compared to rested wakefulness. Conclusion: Acute total sleep deprivation decreases brain activation in the fronto-parietal attention network (prefrontal cortex and intraparietal sulcus) and in the salience network (insula and medial frontal cortex). Increased thalamic activation after sleep deprivation may reflect a complex interaction between the de-arousing effects of sleep loss and the arousing effects of task performance on thalamic activity. Citation: Ma N, Dinges DF, Basner M, Rao H. How acute total sleep loss affects the attending brain: a meta-analysis of neuroimaging studies. SLEEP 2015;38(2):233–240. PMID:25409102

Brain region-specific deficit in mitochondrial electron transport chain complexes in children with autism.

PubMed

Chauhan, Abha; Gu, Feng; Essa, Musthafa M; Wegiel, Jerzy; Kaur, Kulbir; Brown, William Ted; Chauhan, Ved

2011-04-01

Mitochondria play important roles in generation of free radicals, ATP formation, and in apoptosis. We studied the levels of mitochondrial electron transport chain (ETC) complexes, that is, complexes I, II, III, IV, and V, in brain tissue samples from the cerebellum and the frontal, parietal, occipital, and temporal cortices of subjects with autism and age-matched control subjects. The subjects were divided into two groups according to their ages: Group A (children, ages 4-10 years) and Group B (adults, ages 14-39 years). In Group A, we observed significantly lower levels of complexes III and V in the cerebellum (p<0.05), of complex I in the frontal cortex (p<0.05), and of complexes II (p<0.01), III (p<0.01), and V (p<0.05) in the temporal cortex of children with autism as compared to age-matched control subjects, while none of the five ETC complexes was affected in the parietal and occipital cortices in subjects with autism. In the cerebellum and temporal cortex, no overlap was observed in the levels of these ETC complexes between subjects with autism and control subjects. In the frontal cortex of Group A, a lower level of ETC complexes was observed in a subset of autism cases, that is, 60% (3/5) for complexes I, II, and V, and 40% (2/5) for complexes III and IV. A striking observation was that the levels of ETC complexes were similar in adult subjects with autism and control subjects (Group B). A significant increase in the levels of lipid hydroperoxides, an oxidative stress marker, was also observed in the cerebellum and temporal cortex in the children with autism. These results suggest that the expression of ETC complexes is decreased in the cerebellum and the frontal and temporal regions of the brain in children with autism, which may lead to abnormal energy metabolism and oxidative stress. The deficits observed in the levels of ETC complexes in children with autism may readjust to normal levels by adulthood. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

Brain region-specific deficit in mitochondrial electron transport chain complexes in children with autism

PubMed Central

Chauhan, Abha; Gu, Feng; Essa, Musthafa M.; Wegiel, Jerzy; Kaur, Kulbir; Brown, William Ted; Chauhan, Ved

2016-01-01

Mitochondria play important roles in generation of free radicals, ATP formation, and in apoptosis. We studied the levels of mitochondrial electron transport chain (ETC) complexes, that is, complexes I, II, III, IV, and V, in brain tissue samples from the cerebellum and the frontal, parietal, occipital, and temporal cortices of subjects with autism and age-matched control subjects. The subjects were divided into two groups according to their ages: Group A (children, ages 4–10 years) and Group B (adults, ages 14–39 years). In Group A, we observed significantly lower levels of complexes III and V in the cerebellum (p < 0.05), of complex I in the frontal cortex (p < 0.05), and of complexes II (p < 0.01), III (p<0.01), and V (p < 0.05) in the temporal cortex of children with autism as compared to age-matched control subjects, while none of the five ETC complexes was affected in the parietal and occipital cortices in subjects with autism. In the cerebellum and temporal cortex, no overlap was observed in the levels of these ETC complexes between subjects with autism and control subjects. In the frontal cortex of Group A, a lower level of ETC complexes was observed in a subset of autism cases, that is, 60% (3/5) for complexes I, II, and V, and 40% (2/5) for complexes III and IV. A striking observation was that the levels of ETC complexes were similar in adult subjects with autism and control subjects (Group B). A significant increase in the levels of lipid hydroperoxides, an oxidative stress marker, was also observed in the cerebellum and temporal cortex in the children with autism. These results suggest that the expression of ETC complexes is decreased in the cerebellum and the frontal and temporal regions of the brain in children with autism, which may lead to abnormal energy metabolism and oxidative stress. The deficits observed in the levels of ETC complexes in children with autism may readjust to normal levels by adulthood. PMID:21250997

Frontal and Parietal Cortical Interactions with Distributed Visual Representations during Selective Attention and Action Selection

PubMed Central

Stokes, Mark; Nobre, Anna C.; Rushworth, Matthew F. S.

2013-01-01

Using multivoxel pattern analysis (MVPA), we studied how distributed visual representations in human occipitotemporal cortex are modulated by attention and link their modulation to concurrent activity in frontal and parietal cortex. We detected similar occipitotemporal patterns during a simple visuoperceptual task and an attention-to-working-memory task in which one or two stimuli were cued before being presented among other pictures. Pattern strength varied from highest to lowest when the stimulus was the exclusive focus of attention, a conjoint focus, and when it was potentially distracting. Although qualitatively similar effects were seen inside regions relatively specialized for the stimulus category and outside, the former were quantitatively stronger. By regressing occipitotemporal pattern strength against activity elsewhere in the brain, we identified frontal and parietal areas exerting top-down control over, or reading information out from, distributed patterns in occipitotemporal cortex. Their interactions with patterns inside regions relatively specialized for that stimulus category were higher than those with patterns outside those regions and varied in strength as a function of the attentional condition. One area, the frontal operculum, was distinguished by selectively interacting with occipitotemporal patterns only when they were the focus of attention. There was no evidence that any frontal or parietal area actively inhibited occipitotemporal representations even when they should be ignored and were suppressed. Using MVPA to decode information within these frontal and parietal areas showed that they contained information about attentional context and/or readout information from occipitotemporal cortex to guide behavior but that frontal regions lacked information about category identity. PMID:24133250

Frontal and parietal cortical interactions with distributed visual representations during selective attention and action selection.

PubMed

Nelissen, Natalie; Stokes, Mark; Nobre, Anna C; Rushworth, Matthew F S

2013-10-16

Using multivoxel pattern analysis (MVPA), we studied how distributed visual representations in human occipitotemporal cortex are modulated by attention and link their modulation to concurrent activity in frontal and parietal cortex. We detected similar occipitotemporal patterns during a simple visuoperceptual task and an attention-to-working-memory task in which one or two stimuli were cued before being presented among other pictures. Pattern strength varied from highest to lowest when the stimulus was the exclusive focus of attention, a conjoint focus, and when it was potentially distracting. Although qualitatively similar effects were seen inside regions relatively specialized for the stimulus category and outside, the former were quantitatively stronger. By regressing occipitotemporal pattern strength against activity elsewhere in the brain, we identified frontal and parietal areas exerting top-down control over, or reading information out from, distributed patterns in occipitotemporal cortex. Their interactions with patterns inside regions relatively specialized for that stimulus category were higher than those with patterns outside those regions and varied in strength as a function of the attentional condition. One area, the frontal operculum, was distinguished by selectively interacting with occipitotemporal patterns only when they were the focus of attention. There was no evidence that any frontal or parietal area actively inhibited occipitotemporal representations even when they should be ignored and were suppressed. Using MVPA to decode information within these frontal and parietal areas showed that they contained information about attentional context and/or readout information from occipitotemporal cortex to guide behavior but that frontal regions lacked information about category identity.

Altered regional homogeneity in patients with late monocular blindness: a resting-state functional MRI study

PubMed Central

Huang, Xin; Ye, Cheng-Long; Zhong, Yu-Lin; Ye, Lei; Yang, Qi-Chen; Li, Hai-Jun; Jiang, Nan; Peng, De-Chang

2017-01-01

Many previous studies have demonstrated that the blindness patients have has functional and anatomical abnormalities in the visual and other vision-related cortex. However, changes in the brain function in late monocular blindness (MB) at rest are largely unknown. In this study, we investigated the underlying regional homogeneity (ReHo) of brain-activity abnormalities in patients with late MB and their relationship with clinical features. A total of 32 patients with MB (25 male and seven female) and 32 healthy controls (HCs) (25 male and seven female) closely matched in age, sex, and education underwent resting-state functional MRI scans. The ReHo method was used to assess local features of spontaneous brain activities. Patients with MB were distinguishable from HCs using the receiver operating characteristic curve. The relationship between the mean ReHo in brain regions and the behavioral performance was calculated using correlation analysis. Compared with HCs, patients with MB showed significantly decreased ReHo values in the right rectal gyrus, right cuneus, right anterior cingulate, and right lateral occipital cortex and increased ReHo values in the right inferior temporal gyrus, right frontal middle orbital, left posterior cingulate/precuneus, and left middle frontal gyrus. However, there was no significant relationship between the different mean ReHo values in the brain regions and the clinical features. Late MB involves abnormalities of the visual cortex and other vision-related brain regions, which may reflect brain dysfunction in these regions. PMID:28858036

Effects of weightlessness on neurotransmitter receptors in selected brain areas

NASA Technical Reports Server (NTRS)

Miller, J. D.; Murakami, D. M.; Mcmillen, B. A.; Mcconnaughey, M. M.; Williams, H. L.

1985-01-01

The central nervous system receptor dynamics of rats exposed to 7 days of microgravity are studied. The receptor affinity and receptor number at the hippocampus, lateral frontal cortex, prefrontal cortex, corpus striatum, cerebellum and pons-medulla, and the Na(+)/K(+)ATPase activity are examined. The data reveal that there is no significant change in the receptor affinity and receptor number for the lateral frontal cortex, prefrontal cortex, cerebellum and pons-medulla; however, there is an increase from 81 + or - 11 to 120 + or 5 fmole/mg protein in the receptor number for hippocampal binding, and a decrease in receptor number for the striatum from 172 + or - 14 to 143 + or - 10 fmoles/mg protein. A 9 percent decrease in Mg-dependent Na(+)/K(+)ATPase activity is observed. It is detected that the terminal mechanism may be affected by exposure to microgravity.

Left Inferior Frontal Cortex and Syntax: Function, Structure and Behaviour in Patients with Left Hemisphere Damage

ERIC Educational Resources Information Center

Tyler, Lorraine K.; Marslen-Wilson, William D.; Randall, Billi; Wright, Paul; Devereux, Barry J.; Zhuang, Jie; Papoutsi, Marina; Stamatakis, Emmanuel A.

2011-01-01

For the past 150 years, neurobiological models of language have debated the role of key brain regions in language function. One consistently debated set of issues concern the role of the left inferior frontal gyrus in syntactic processing. Here we combine measures of functional activity, grey matter integrity and performance in patients with left…

Preserved speech abilities and compensation following prefrontal damage.

PubMed

Buckner, R L; Corbetta, M; Schatz, J; Raichle, M E; Petersen, S E

1996-02-06

Lesions to left frontal cortex in humans produce speech production impairments (nonfluent aphasia). These impairments vary from subject to subject and performance on certain speech production tasks can be relatively preserved in some patients. A possible explanation for preservation of function under these circumstances is that areas outside left prefrontal cortex are used to compensate for the injured brain area. We report here a direct demonstration of preserved language function in a stroke patient (LF1) apparently due to the activation of a compensatory brain pathway. We used functional brain imaging with positron emission tomography (PET) as a basis for this study.

The auditory and non-auditory brain areas involved in tinnitus. An emergent property of multiple parallel overlapping subnetworks

PubMed Central

Vanneste, Sven; De Ridder, Dirk

2012-01-01

Tinnitus is the perception of a sound in the absence of an external sound source. It is characterized by sensory components such as the perceived loudness, the lateralization, the tinnitus type (pure tone, noise-like) and associated emotional components, such as distress and mood changes. Source localization of quantitative electroencephalography (qEEG) data demonstrate the involvement of auditory brain areas as well as several non-auditory brain areas such as the anterior cingulate cortex (dorsal and subgenual), auditory cortex (primary and secondary), dorsal lateral prefrontal cortex, insula, supplementary motor area, orbitofrontal cortex (including the inferior frontal gyrus), parahippocampus, posterior cingulate cortex and the precuneus, in different aspects of tinnitus. Explaining these non-auditory brain areas as constituents of separable subnetworks, each reflecting a specific aspect of the tinnitus percept increases the explanatory power of the non-auditory brain areas involvement in tinnitus. Thus, the unified percept of tinnitus can be considered an emergent property of multiple parallel dynamically changing and partially overlapping subnetworks, each with a specific spontaneous oscillatory pattern and functional connectivity signature. PMID:22586375

Is evaluation of humorous stimuli associated with frontal cortex morphology? A pilot study using facial micro-movement analysis and MRI.

PubMed

Juckel, Georg; Mergl, Roland; Brüne, Martin; Villeneuve, Isabelle; Frodl, Thomas; Schmitt, Gisela; Zetzsche, Thomas; Born, Christine; Hahn, Klaus; Reiser, Maximilian; Möller, Hans-Jürgen; Bär, Karl-Jürgen; Hegerl, Ulrich; Meisenzahl, Eva Maria

2011-05-01

Humour involves the ability to detect incongruous ideas violating social rules and norms. Accordingly, humour requires a complex array of cognitive skills for which intact frontal lobe functioning is critical. Here, we sought to examine the association of facial expression during an emotion inducing experiment with frontal cortex morphology in healthy subjects. Thirty-one healthy male subjects (mean age: 30.8±8.9 years; all right-handers) watching a humorous movie ("Mr. Bean") were investigated. Markers fixed at certain points of the face emitting high-frequency ultrasonic signals allowed direct measurement of facial movements with high spatial-temporal resolution. Magnetic resonance images of the frontal cortex were obtained with a 1.5-T Magnetom using a coronar T2- and protondensity-weighted Dual-Echo-Sequence and a 3D-magnetization-prepared rapid gradient echo (MPRAGE) sequence. Volumetric analysis was performed using BRAINS. Frontal cortex volume was partly associated with slower speed of "laughing" movements of the eyes ("genuine" or Duchenne smile). Specifically, grey matter volume was associated with longer emotional reaction time ipsilaterally, even when controlled for age and daily alcohol intake. These results lend support to the hypothesis that superior cognitive evaluation of humorous stimuli - mediated by larger prefrontal grey and white matter volume - leads to a measurable reduction of speed of emotional expressivity in normal adults. Copyright © 2010 Elsevier Srl. All rights reserved.

Altered local spontaneous activity in frontal lobe epilepsy: a resting-state functional magnetic resonance imaging study.

PubMed

Dong, Li; Li, Hechun; He, Zhongqiong; Jiang, Sisi; Klugah-Brown, Benjamin; Chen, Lin; Wang, Pu; Tan, Song; Luo, Cheng; Yao, Dezhong

2016-11-01

The purpose of this study was to investigate the local spatiotemporal consistency of spontaneous brain activity in patients with frontal lobe epilepsy (FLE). Eyes closed resting-state functional magnetic resonance imaging (fMRI) data were collected from 19 FLE patients and 19 age- and gender-matched healthy controls. A novel measure, named FOur-dimensional (spatiotemporal) Consistency of local neural Activities (FOCA) was used to assess the spatiotemporal consistency of local spontaneous activity (emphasizing both local temporal homogeneity and regional stability of brain activity states). Then, two-sample t test was performed to detect the FOCA differences between two groups. Partial correlations between the FOCA values and durations of epilepsy were further analyzed. Compared with controls, FLE patients demonstrated increased FOCA in distant brain regions including the frontal and parietal cortices, as well as the basal ganglia. The decreased FOCA was located in the temporal cortex, posterior default model regions, and cerebellum. In addition, the FOCA measure was linked to the duration of epilepsy in basal ganglia. Our study suggested that alterations of local spontaneous activity in frontoparietal cortex and basal ganglia was associated with the pathophysiology of FLE; and the abnormality in frontal and default model regions might account for the potential cognitive impairment in FLE. We also presumed that the FOCA measure had potential to provide important insights into understanding epilepsy such as FLE.

Social Context-Dependent Activity in Marmoset Frontal Cortex Populations during Natural Conversations

PubMed Central

de la Mothe, Lisa; Miller, Cory T.

2017-01-01

Communication is an inherently interactive process that weaves together the fabric of both human and nonhuman primate societies. To investigate the properties of the primate brain during active social signaling, we recorded the responses of frontal cortex neurons as freely moving marmosets engaged in conversational exchanges with a visually occluded virtual marmoset. We found that small changes in firing rate (∼1 Hz) occurred across a broadly distributed population of frontal cortex neurons when marmosets heard a conspecific vocalization, and that these changes corresponded to subjects' likelihood of producing or withholding a vocal reply. Although the contributions of individual neurons were relatively small, large populations of neurons were able to clearly distinguish between these social contexts. Most significantly, this social context-dependent change in firing rate was evident even before subjects heard the vocalization, indicating that the probability of a conversational exchange was determined by the state of the frontal cortex at the time a vocalization was heard, and not by a decision driven by acoustic characteristics of the vocalization. We found that changes in neural activity scaled with the length of the conversation, with greater changes in firing rate evident for longer conversations. These data reveal specific and important facets of this neural activity that constrain its possible roles in active social signaling, and we hypothesize that the close coupling between frontal cortex activity and this natural, active primate social-signaling behavior facilitates social-monitoring mechanisms critical to conversational exchanges. SIGNIFICANCE STATEMENT We provide evidence for a novel pattern of neural activity in the frontal cortex of freely moving, naturally behaving, marmoset monkeys that may facilitate natural primate conversations. We discovered small (∼1 Hz), but reliable, changes in neural activity that occurred before marmosets even heard a conspecific vocalization that, as a population, almost perfectly predicted whether subjects would produce a vocalization in response. The change in the state of the frontal cortex persisted throughout the conversation and its magnitude scaled linearly with the length of the interaction. We hypothesize that this social context-dependent change in frontal cortex activity is supported by several mechanisms, such as social arousal and attention, and facilitates social monitoring critical for vocal coordination characteristic of human and nonhuman primate conversations. PMID:28630255

A comparison of neurodegeneration linked with neuroinflammation in different brain areas of rats after intracerebroventricular colchicine injection.

PubMed

Sil, Susmita; Ghosh, Rupsa; Sanyal, Moumita; Guha, Debjani; Ghosh, Tusharkanti

2016-01-01

Colchicine induces neurodegeneration, but the extent of neurodegeneration in different areas of the brain in relation to neuroinflammation remains unclear. Such information may be useful to allow for the development of a model to compare colchicine-induced neurodegeneration with other neurodegenerative diseases such as Alzheimer's Disease (AD). The present study was designed to investigate the extent of neurodegeneration along with neuroinflammation in different areas of the brain, e.g. frontal cortex, parietal cortex, occipital cortex, corpus striatum, amygdala and hippocampus, in rats along with memory impairment 21 days after a single intracerebroventricular (icv) injection of colchicine. Memory parameters were measured before and after icv colchicine injection in all test groups of rats (control, sham-operated, colchicine-injected [ICIR] rats). On Day 21 post-injection, rats from all groups were anesthesized and tissues from the various brain areas were collected for assessment of biomarkers of neuroinflammation (i.e. levels of ROS, nitrite and proinflammatory cytokines TNFα and IL-1β) and neurodegeneration (assessed histologically). The single injection of colchicine resulted in impaired memory and neurodegeneration (significant presence of plaques, Nissl granule chromatolysis) in various brain areas (frontal cortex, amygdala, parietal cortex, corpus striatum), with maximum severity in the hippocampus. While IL-1β, TNFα, ROS and nitrite levels were altered in different brain areas in the ICIR rats, these parameters had their greatest change in the hippocampus. This study showed that icv injection of colchicine caused strong neurodegeneration and neuroinflammation in the hippocampus of rats and the increases in neurodegeneration were corroborated with those of neuroinflammation at the site. The present study also showed that the extent of neurodegeneration and neuroinflammation in different brain areas of the colchicine-injected rats were AD-like and supported the fact that such rats might have the ability to serve as a sporadic model of AD.

FMRI activity during associative encoding is correlated with cardiorespiratory fitness and source memory performance in older adults

PubMed Central

Hayes, Scott M.; Hayes, Jasmeet P.; Williams, Victoria J.; Liu, Huiting; Verfaellie, Mieke

2017-01-01

Older adults (OA), relative to young adults (YA), exhibit age-related alterations in functional Magnetic Resonance Imaging (fMRI) activity during associative encoding, which contributes to deficits in source memory. Yet, there are remarkable individual differences in brain health and memory performance among OA. Cardiorespiratory fitness (CRF) is one individual difference factor that may attenuate brain aging, and thereby contribute to enhanced source memory in OA. To examine this possibility, 26 OA and 31 YA completed a treadmill-based exercise test to evaluate CRF (peak VO2) and fMRI to examine brain activation during a face-name associative encoding task. Our results indicated that in OA, peak VO2 was positively associated with fMRI activity during associative encoding in multiple regions including bilateral prefrontal cortex, medial frontal cortex, bilateral thalamus and left hippocampus. Next, a conjunction analysis was conducted to assess whether CRF influenced age-related differences in fMRI activation. We classified OA as high or low CRF and compared their activation to YA. High fit OA (HFOA) showed fMRI activation more similar to YA than low fit OA (LFOA) (i.e., reduced age-related differences) in multiple regions including thalamus, posterior and prefrontal cortex. Conversely, in other regions, primarily in prefrontal cortex, HFOA, but not LFOA, demonstrated greater activation than YA (i.e., increased age-related differences). Further, fMRI activity in these brain regions was positively associated with source memory among OA, with a mediation model demonstrating that associative encoding activation in medial frontal cortex indirectly influenced the relationship between peak VO2 and subsequent source memory performance. These results indicate that CRF may contribute to neuroplasticity among OA, reducing age-related differences in some brain regions, consistent with the brain maintenance hypothesis, but accentuating age-differences in other regions, consistent with the brain compensation hypothesis. PMID:28161031

FMRI activity during associative encoding is correlated with cardiorespiratory fitness and source memory performance in older adults.

PubMed

Hayes, Scott M; Hayes, Jasmeet P; Williams, Victoria J; Liu, Huiting; Verfaellie, Mieke

2017-06-01

Older adults (OA), relative to young adults (YA), exhibit age-related alterations in functional Magnetic Resonance Imaging (fMRI) activity during associative encoding, which contributes to deficits in source memory. Yet, there are remarkable individual differences in brain health and memory performance among OA. Cardiorespiratory fitness (CRF) is one individual difference factor that may attenuate brain aging, and thereby contribute to enhanced source memory in OA. To examine this possibility, 26 OA and 31 YA completed a treadmill-based exercise test to evaluate CRF (peak VO 2 ) and fMRI to examine brain activation during a face-name associative encoding task. Our results indicated that in OA, peak VO 2 was positively associated with fMRI activity during associative encoding in multiple regions including bilateral prefrontal cortex, medial frontal cortex, bilateral thalamus and left hippocampus. Next, a conjunction analysis was conducted to assess whether CRF influenced age-related differences in fMRI activation. We classified OA as high or low CRF and compared their activation to YA. High fit OA (HFOA) showed fMRI activation more similar to YA than low fit OA (LFOA) (i.e., reduced age-related differences) in multiple regions including thalamus, posterior and prefrontal cortex. Conversely, in other regions, primarily in prefrontal cortex, HFOA, but not LFOA, demonstrated greater activation than YA (i.e., increased age-related differences). Further, fMRI activity in these brain regions was positively associated with source memory among OA, with a mediation model demonstrating that associative encoding activation in medial frontal cortex indirectly influenced the relationship between peak VO 2 and subsequent source memory performance. These results indicate that CRF may contribute to neuroplasticity among OA, reducing age-related differences in some brain regions, consistent with the brain maintenance hypothesis, but accentuating age-differences in other regions, consistent with the brain compensation hypothesis. Published by Elsevier Ltd.

[Amplitude Changes of Low Frequency Fluctuation in Brain Spontaneous Nervous Activities Induced by Needling at Hand Taiyin Lung Channel].

PubMed

Zhou, You-long; Su, Cheng-guo; Liu, Shou-fang; Jin, Xiang-yu; Duan, Yan-li; Chen, Xiao-yan; Zhao, Shu-hua; Wang, Quan-liang; Dang, Chang-lin

2016-05-01

To observe amplitude changes of low frequency fluctuation in brain spontaneous nervous activities induced by needling at Hand Taiyin Lung Channel, and to preliminarily explore the possible brain function network of Hand Taiyin Lung Channel. By using functional magnetic resonance imaging (fMRI), 16 healthy volunteers underwent resting-state scanning (R1) and scanning with retained acupuncture at Hand Taiyin Lung Channel (acupuncture, AP). Data of fMRI collected were statistically calculated using amplitude of low frequency fluctuations (ALFF). Under R1 significantly enhanced ALFF occurred in right precuneus, left inferior parietal lobule, bilateral superior temporal gyrus, bilateral middle frontal gyrus, left superior frontal gyrus, left inferior frontal gyrus, left medial frontal gyrus. Under AP significantly enhanced ALFF occurred in right precuneus, bilateral superior frontal gyrus, cerebellum, bilateral middle frontal gyrus, right medial frontal gyrus, and so on. Compared with R1, needing at Hand Taiyin Lung Channel could significantly enhance ALFF in right gyrus subcallosum and right inferior frontal gyrus. Significant decreased ALFF appeared in right postcentral gyrus, left precuneus, left superior temporal gyrus, left middle temporal gyrus, and so on. Needing at Hand Taiyin Lung Channel could significantly change fixed activities of cerebral cortex, especially in right subcallosal gyrus, right inferior frontal gyrus, and so on.

Adverse Effects of Cannabis on Adolescent Brain Development: A Longitudinal Study

PubMed Central

Camchong, Jazmin; Lim, Kelvin O; Kumra, Sanjiv

2017-01-01

Abstract Cannabis is widely perceived as a safe recreational drug and its use is increasing in youth. It is important to understand the implications of cannabis use during childhood and adolescence on brain development. This is the first longitudinal study that compared resting functional connectivity of frontally mediated networks between 43 healthy controls (HCs; 20 females; age M = 16.5 ± 2.7) and 22 treatment-seeking adolescents with cannabis use disorder (CUD; 8 females; age M = 17.6 ± 2.4). Increases in resting functional connectivity between caudal anterior cingulate cortex (ACC) and superior frontal gyrus across time were found in HC, but not in CUD. CUD showed a decrease in functional connectivity between caudal ACC and dorsolateral and orbitofrontal cortices across time. Lower functional connectivity between caudal ACC cortex and orbitofrontal cortex at baseline predicted higher amounts of cannabis use during the following 18 months. Finally, high amounts of cannabis use during the 18-month interval predicted lower intelligence quotient and slower cognitive function measured at follow-up. These data provide compelling longitudinal evidence suggesting that repeated exposure to cannabis during adolescence may have detrimental effects on brain resting functional connectivity, intelligence, and cognitive function. PMID:26912785

Biased and unbiased perceptual decision-making on vocal emotions.

PubMed

Dricu, Mihai; Ceravolo, Leonardo; Grandjean, Didier; Frühholz, Sascha

2017-11-24

Perceptual decision-making on emotions involves gathering sensory information about the affective state of another person and forming a decision on the likelihood of a particular state. These perceptual decisions can be of varying complexity as determined by different contexts. We used functional magnetic resonance imaging and a region of interest approach to investigate the brain activation and functional connectivity behind two forms of perceptual decision-making. More complex unbiased decisions on affective voices recruited an extended bilateral network consisting of the posterior inferior frontal cortex, the orbitofrontal cortex, the amygdala, and voice-sensitive areas in the auditory cortex. Less complex biased decisions on affective voices distinctly recruited the right mid inferior frontal cortex, pointing to a functional distinction in this region following decisional requirements. Furthermore, task-induced neural connectivity revealed stronger connections between these frontal, auditory, and limbic regions during unbiased relative to biased decision-making on affective voices. Together, the data shows that different types of perceptual decision-making on auditory emotions have distinct patterns of activations and functional coupling that follow the decisional strategies and cognitive mechanisms involved during these perceptual decisions.

Increased Cortical Thickness in Male-to-Female Transsexualism

PubMed Central

Luders, Eileen; Sánchez, Francisco J.; Tosun, Duygu; Shattuck, David W.; Gaser, Christian; Vilain, Eric; Toga, Arthur W.

2013-01-01

Background The degree to which one identifies as male or female has a profound impact on one’s life. Yet, there is a limited understanding of what contributes to this important characteristic termed gender identity. In order to reveal factors influencing gender identity, studies have focused on people who report strong feelings of being the opposite sex, such as male-to-female (MTF) transsexuals. Method To investigate potential neuroanatomical variations associated with transsexualism, we compared the regional thickness of the cerebral cortex between 24 MTF transsexuals who had not yet been treated with cross-sex hormones and 24 age-matched control males. Results Results revealed thicker cortices in MTF transsexuals, both within regions of the left hemisphere (i.e., frontal and orbito-frontal cortex, central sulcus, perisylvian regions, paracentral gyrus) and right hemisphere (i.e., pre-/post-central gyrus, parietal cortex, temporal cortex, precuneus, fusiform, lingual, and orbito-frontal gyrus). Conclusion These findings provide further evidence that brain anatomy is associated with gender identity, where measures in MTF transsexuals appear to be shifted away from gender-congruent men. PMID:23724358

Midline Frontal Cortex Low-Frequency Activity Drives Subthalamic Nucleus Oscillations during Conflict

PubMed Central

Zavala, Baltazar A.; Tan, Huiling; Little, Simon; Ashkan, Keyoumars; Hariz, Marwan; Foltynie, Thomas; Zrinzo, Ludvic; Zaghloul, Kareem A.

2014-01-01

Making the right decision from conflicting information takes time. Recent computational, electrophysiological, and clinical studies have implicated two brain areas as being crucial in assuring sufficient time is taken for decision-making under conditions of conflict: the medial prefrontal cortex and the subthalamic nucleus (STN). Both structures exhibit an elevation of activity at low frequencies (<10 Hz) during conflict that correlates with the amount of time taken to respond. This suggests that the two sites could become functionally coupled during conflict. To establish the nature of this interaction we recorded from deep-brain stimulation electrodes implanted bilaterally in the STN of 13 Parkinson's disease patients while they performed a sensory integration task involving randomly moving dots. By gradually increasing the number of dots moving coherently in one direction, we were able to determine changes in the STN associated with response execution. Furthermore, by occasionally having 10% of the dots move in the opposite direction as the majority, we were able to identify an independent increase in STN theta-delta activity triggered by conflict. Crucially, simultaneous midline frontal electroencephalographic recordings revealed an increase in the theta-delta band coherence between the two structures that was specific to high-conflict trials. Activity over the midline frontal cortex was Granger causal to that in STN. These results establish the cortico-subcortical circuit enabling successful choices to be made under conditions of conflict and provide support for the hypothesis that the brain uses frequency-specific channels of communication to convey behaviorally relevant information. PMID:24849364

Cortical grey matter volume reduction in people with schizophrenia is associated with neuro-inflammation

PubMed Central

Zhang, Y; Catts, V S; Sheedy, D; McCrossin, T; Kril, J J; Shannon Weickert, C

2016-01-01

Cortical grey matter volume deficits and neuro-inflammation exist in patients with schizophrenia, although it is not clear whether elevated cytokines contribute to the cortical volume reduction. We quantified cortical and regional brain volumes in fixed postmortem brains from people with schizophrenia and matched controls using stereology. Interleukin (IL)-6, IL-1β, IL-8 and SERPINA3 messenger RNAs (mRNAs) were quantified in the contralateral fresh frozen orbitofrontal cortex. We found a small, but significant reduction in cortical grey matter (1.3% F(1,85)=4.478, P=0.037) and superior frontal gyrus (6.5% F(1,80)=5.700, P=0.019) volumes in individuals with schizophrenia compared with controls. Significantly reduced cortical grey matter (9.2% F(1,24)=8.272, P=0.008) and superior frontal gyrus (13.9% F(1,20)=5.374, P=0.031) volumes were found in cases with schizophrenia and ‘high inflammation' status relative to schizophrenia cases with ‘low inflammation' status in the prefrontal cortex. The expression of inflammatory mRNAs in the orbitofrontal cortex was significantly correlated with those in dorsolateral prefrontal cortex (all r>0.417, all P<0.022), except for IL-8. Moreover, average daily and lifetime antipsychotic intake negatively correlated with cortical grey matter and superior frontal gyrus volumes (all r<−0.362, all P<0.05). The results suggest that the reduction in cortical grey matter volume in people with schizophrenia is exaggerated in those who have high expression of inflammatory cytokines. Further, antipsychotic medication intake does not appear to ameliorate the reduction in brain volume. PMID:27959331

Alkali metals levels in the human brain tissue: Anatomical region differences and age-related changes.

PubMed

Ramos, Patrícia; Santos, Agostinho; Pinto, Edgar; Pinto, Nair Rosas; Mendes, Ricardo; Magalhães, Teresa; Almeida, Agostinho

2016-12-01

The link between trace elements imbalances (both "toxic" and "essential") in the human brain and neurodegenerative disease has been subject of extensive research. More recently, some studies have highlighted the potential role of the homeostasis deregulation of alkali metals in specific brain regions as key factor in the pathogenesis of neurodegenerative diseases such as multiple sclerosis and Alzheimer's disease. Using flame atomic emission spectrometry and inductively coupled plasma-mass spectrometry after microwave-assisted acid digestion of the samples, alkali metals (Na, K, Li, Rb and Cs) were determined in 14 different areas of the human brain (frontal cortex, superior and middle temporal gyri, caudate nucleus, putamen, globus pallidus, cingulated gyrus, hippocampus, inferior parietal lobule, visual cortex of the occipital lobe, midbrain, pons, medulla and cerebellum) of adult individuals (n=42; 71±12, range: 50-101 years old) with no known history and evidence of neurodegenerative, neurological or psychiatric disorder. Potassium was found as the most abundant alkali metal, followed by Na, Rb, Cs and Li. Lithium, K and Cs distribution showed to be quite heterogeneous. On the contrary, Rb and Na appeared quite homogeneously distributed within the human brain tissue. The lowest levels of Na, K, Rb and Li were found in the brainstem (midbrain, medulla and pons) and cerebellum, while the lowest levels of Cs were found in the frontal cortex. The highest levels of K (mean±sd; range 15.5±2.5; 8.9-21.8mg/g) Rb (17.2±6.1; 3.9-32.4μg/g and Cs (83.4±48.6; 17.3-220.5ng/g) were found in putamen. The highest levels of Na and Li were found in the frontal cortex (11.6±2.4; 6.6-17.1mg/g) and caudate nucleus (7.6±4.6 2.2-21.3ng/g), respectively. Although K, Cs and Li levels appear to remain largely unchanged with age, some age-related changes were observed for Na and Rb levels in particular brain regions (namely in the hippocampus). Copyright © 2016 Elsevier GmbH. All rights reserved.

Valeriana wallichii root extract improves sleep quality and modulates brain monoamine level in rats.

PubMed

Sahu, Surajit; Ray, Koushik; Yogendra Kumar, M S; Gupta, Shilpa; Kauser, Hina; Kumar, Sanjeev; Mishra, Kshipra; Panjwani, Usha

2012-07-15

The present study was performed to investigate the effects of Valeriana wallichi (VW) aqueous root extract on sleep-wake profile and level of brain monoamines on Sprague-Dawley rats. Electrodes and transmitters were implanted to record EEG and EMG in freely moving condition and the changes were recorded telemetrically after oral administration of VW in the doses of 100, 200 and 300 mg/kg body weight. Sleep latency was decreased and duration of non-rapid eye movement (NREM) sleep was increased in a dose dependent manner. A significant decrease of sleep latency and duration of wakefulness were observed with VW at doses of 200 and 300 mg/kg. Duration of NREM sleep as well as duration of total sleep was increased significantly after treatment with VW at the doses of 200 and 300 mg/kg. VW also increased EEG slow wave activity during NREM sleep at the doses of 200 and 300 mg/kg. Level of norepinephrine (NE), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), serotonin (5-HT) and hydroxy indole acetic acid (HIAA) were measured in frontal cortex and brain stem after VW treatment at the dose of 200mg/kg. NE and 5HT level were decreased significantly in both frontal cortex and brain stem. DA and HIAA level significantly decreased only in cortex. DOPAC level was not changed in any brain region studied. In conclusion it can be said that VW water extract has a sleep quality improving effect which may be dependent upon levels of monoamines in cortex and brainstem. Copyright © 2012 Elsevier GmbH. All rights reserved.

Antidepressant-like effects of ferulic acid: involvement of serotonergic and norepinergic systems.

PubMed

Chen, Jianliang; Lin, Dan; Zhang, Chong; Li, Gaowen; Zhang, Nianping; Ruan, Lina; Yan, Qizhi; Li, Jianxin; Yu, Xuefeng; Xie, Xupei; Pang, Cong; Cao, Liang; Pan, Jianchun; Xu, Ying

2015-02-01

Ferulic acid is a polyphenol that has antioxidant, anti-inflammatory and anticancer properties. The present study analyzed the antidepressant-like potential of ferulic acid using two well-validated mouse models of despair test, tail suspension and forced swim tests. The results suggested that ferulic acid treatment at doses of 10, 20, 40 and 80 mg/kg (p.o.) significantly reduced the immobility time in both of these two tests. These doses that affected the depressive-like behaviors did now show any effect on locomotion counts. The further neurochemical assays suggested that ferulic acid increased monoamine neurotransmitter levels in the brain regions that are relative to mood disorders: the hippocampus and frontal cortex. The increased tend to serotonin and norepinephrine was also found in the hypothalamus after higher dose of ferulic acid treatment. The subsequent study suggested that monoamine oxidase A (MAO-A) activity was inhibited in the frontal cortex and hippocampus when treatment with 40 and 80 mg/kg ferulic acid; while MAO-B activity did not change significantly. The current study provides the first lines of evidence that serotonin and norepinephrine, but not dopamine levels were elevated in mouse hippocampus and frontal cortex after ferulic acid treatment. These changes may be attributable to the inhibition of MAO-A activities in the same brain regions.

N-Acetyl and Glutamatergic Neurometabolites in Perisylvian Brain Regions of Methamphetamine Users.

PubMed

Tang, Jinsong; O'Neill, Joseph; Alger, Jeffry R; Shen, Zhiwei; Johnson, Maritza C; London, Edythe D

2018-05-21

Methamphetamine induces neuronal N-acetyl-aspartate synthesis in preclinical studies. In a preliminary human proton magnetic resonance spectroscopic imaging investigation, we also observed that N-acetyl-aspartate+N-acetyl-aspartyl-glutamate in right inferior frontal cortex correlated with years of heavy methamphetamine abuse. In the same brain region, glutamate+glutamine is lower in methamphetamine users than in controls and is negatively correlated with depression. N-acetyl and glutamatergic neurochemistries therefore merit further investigation in methamphetamine abuse and the associated mood symptoms. Magnetic resonance spectroscopic imaging was used to measure N-acetyl-aspartate+N-acetyl-aspartyl-glutamate and glutamate+glutamine in bilateral inferior frontal cortex and insula, a neighboring perisylvian region affected by methamphetamine, of 45 abstinent methamphetamine-dependent and 45 healthy control participants. Regional neurometabolite levels were tested for group differences and associations with duration of heavy methamphetamine use, depressive symptoms, and state anxiety. In right inferior frontal cortex, N-acetyl-aspartate+N-acetyl-aspartyl-glutamate correlated with years of heavy methamphetamine use (r = +0.45); glutamate+glutamine was lower in methamphetamine users than in controls (9.3%) and correlated negatively with depressive symptoms (r = -0.44). In left insula, N-acetyl-aspartate+N-acetyl-aspartyl-glutamate was 9.1% higher in methamphetamine users than controls. In right insula, glutamate+glutamine was 12.3% lower in methamphetamine users than controls and correlated negatively with depressive symptoms (r = -0.51) and state anxiety (r = -0.47). The inferior frontal cortex and insula show methamphetamine-related abnormalities, consistent with prior observations of increased cortical N-acetyl-aspartate in methamphetamine-exposed animal models and associations between cortical glutamate and mood in human methamphetamine users.

Monoamine oxidase-A and B activities in the cerebellum and frontal cortex of children and young adults with autism.

PubMed

Gu, Feng; Chauhan, Ved; Chauhan, Abha

2017-10-01

Monoamine oxidases (MAOs) catalyze the metabolism of monoamine neurotransmitters, such as serotonin, dopamine, and norepinephrine, and are key regulators for brain function. In this study, we analyzed the activities of MAO-A and MAO-B in the cerebellum and frontal cortex from subjects with autism and age-matched control subjects. In the cerebellum, MAO-A activity in subjects with autism (aged 4-38 years) was significantly lower by 20.6% than in controls. When the subjects were divided into children (aged 4-12 years) and young adults (aged 13-38 years) subgroups, a significant decrease by 27.8% in the MAO-A activity was observed only in children with autism compared with controls. When the 95% confidence interval of the control group was taken as a reference range, reduced activity of MAO-A was observed in 70% of children with autism. In the frontal cortex, MAO-A activity in children with autism was also lower by 30% than in the control group, and impaired activity of MAO-A was observed in 55.6% of children with autism, although the difference between the autism and control groups was not significant when all subjects were considered. On the contrary, there was no significant difference in MAO-B activity in both the cerebellum and frontal cortex between children with autism and the control group as well as in adults. These results suggest impaired MAO-A activity in the brain of subjects with autism, especially in children with autism. Decreased activity of MAOs may lead to increased levels of monoaminergic neurotransmitters, such as serotonin, which have been suggested to have a critical role in autism. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Dynamic diaschisis: anatomically remote and context-sensitive human brain lesions.

PubMed

Price, C J; Warburton, E A; Moore, C J; Frackowiak, R S; Friston, K J

2001-05-15

Functional neuroimaging was used to investigate how lesions to the Broca's area impair neuronal responses in remote undamaged cortical regions. Four patients with speech output problems, but relatively preserved comprehension, were scanned while viewing words relative to consonant letter strings. In normal subjects, this results in left lateralized activation in the posterior inferior frontal, middle temporal, and posterior inferior temporal cortices. Each patient activated normally in the middle temporal region but abnormally in the damaged posterior inferior frontal cortex and the undamaged posterior inferior temporal cortex. In the damaged frontal region, activity was insensitive to the presence of words but in the undamaged posterior inferior temporal region, activity decreased in the presence of words rather than increasing as it did in the normal individuals. The reversal of responses in the left posterior inferior temporal region illustrate the context-sensitive nature of the abnormality and that failure to activate the left posterior temporal region could not simply be accounted for by insufficient demands on the underlying function. We propose that, in normal individuals, visual word presentation changes the effective connectivity among reading areas and, in patients, posterior temporal responses are abnormal when they depend upon inputs from the damaged inferior frontal cortex. Our results serve to introduce the concept of dynamic diaschisis; the anatomically remote and context-sensitive effects of focal brain lesions. Dynamic diaschisis reveals abnormalities of functional integration that may have profound implications for neuropsychological inference, functional anatomy and, vicariously, cognitive rehabilitation.

What’s special about task in dystonia? A voxel-based morphometry and diffusion weighted imaging study

PubMed Central

Ramdhani, Ritesh A.; Kumar, Veena; Velickovic, Miodrag; Frucht, Steven J.; Tagliati, Michele; Simonyan, Kristina

2014-01-01

Background Numerous brain imaging studies have demonstrated structural changes in the basal ganglia, thalamus, sensorimotor cortex and cerebellum across different forms of primary dystonia. However, our understanding of brain abnormalities contributing to the clinically well-described phenomenon of task-specificity in dystonia remained limited. Methods We used high-resolution MRI with voxel-based morphometry and diffusion tensor imaging with tract-based spatial statistics of fractional anisotropy to examine gray and white matter organization in two task-specific dystonia forms, writer’s cramp and laryngeal dystonia, and two non-task-specific dystonia forms, cervical dystonia and blepharospasm. Results A direct comparison between the both dystonia forms revealed that characteristic gray matter volumetric changes in task-specific dystonia involve the brain regions responsible for sensorimotor control during writing and speaking, such as primary somatosensory cortex, middle frontal gyrus, superior/inferior temporal gyrus, middle/posterior cingulate cortex, occipital cortex as well as the striatum and cerebellum (lobules VI-VIIa). These gray matter changes were accompanied by white matter abnormalities in the premotor cortex, middle/inferior frontal gyrus, genu of the corpus callosum, anterior limb/genu of the internal capsule, and putamen. Conversely, gray matter volumetric changes in non-task-specific group were limited to the left cerebellum (lobule VIIa) only, while white matter alterations were found to underlie the primary sensorimotor cortex, inferior parietal lobule and middle cingulate gyrus. Conclusion Distinct microstructural patterns in task-specific and non-task-specific dystonias may represent neuroimaging markers and provide evidence that these two dystonia subclasses likely follow divergent pathophysiological mechanisms precipitated by different triggers. PMID:24925463

Neural correlates of the severity of cocaine, heroin, alcohol, MDMA and cannabis use in polysubstance abusers: a resting-PET brain metabolism study.

PubMed

Moreno-López, Laura; Stamatakis, Emmanuel A; Fernández-Serrano, Maria José; Gómez-Río, Manuel; Rodríguez-Fernández, Antonio; Pérez-García, Miguel; Verdejo-García, Antonio

2012-01-01

Functional imaging studies of addiction following protracted abstinence have not been systematically conducted to look at the associations between severity of use of different drugs and brain dysfunction. Findings from such studies may be relevant to implement specific interventions for treatment. The aim of this study was to examine the association between resting-state regional brain metabolism (measured with 18F-fluorodeoxyglucose Positron Emission Tomography (FDG-PET) and the severity of use of cocaine, heroin, alcohol, MDMA and cannabis in a sample of polysubstance users with prolonged abstinence from all drugs used. Our sample consisted of 49 polysubstance users enrolled in residential treatment. We conducted correlation analyses between estimates of use of cocaine, heroin, alcohol, MDMA and cannabis and brain metabolism (BM) (using Statistical Parametric Mapping voxel-based (VB) whole-brain analyses). In all correlation analyses conducted for each of the drugs we controlled for the co-abuse of the other drugs used. The analysis showed significant negative correlations between severity of heroin, alcohol, MDMA and cannabis use and BM in the dorsolateral prefrontal cortex (DLPFC) and temporal cortex. Alcohol use was further associated with lower metabolism in frontal premotor cortex and putamen, and stimulants use with parietal cortex. Duration of use of different drugs negatively correlated with overlapping regions in the DLPFC, whereas severity of cocaine, heroin and alcohol use selectively impact parietal, temporal, and frontal-premotor/basal ganglia regions respectively. The knowledge of these associations could be useful in the clinical practice since different brain alterations have been associated with different patterns of execution that may affect the rehabilitation of these patients.

Developmental Differences in Error-Related ERPs in Middle- to Late-Adolescent Males

ERIC Educational Resources Information Center

Santesso, Diane L.; Segalowitz, Sidney J.

2008-01-01

Although there are some studies documenting structural brain changes during late adolescence, there are few showing functional brain changes over this period in humans. Of special interest would be functional changes in the medial frontal cortex that reflect response monitoring. In order to examine such age-related differences, the authors…

Comparison of Brain Activity during Drawing and Clay Sculpting: A Preliminary qEEG Study

ERIC Educational Resources Information Center

Kruk, Kerry A.; Aravich, Paul F.; Deaver, Sarah P.; deBeus, Roger

2014-01-01

A preliminary experimental study examined brain wave frequency patterns of female participants (N = 14) engaged in two different art making conditions: clay sculpting and drawing. After controlling for nonspecific effects of movement, quantitative electroencephalographic (qEEG) recordings were made of the bilateral medial frontal cortex and…

Recovery of brain abscess-induced stuttering after neurosurgical intervention.

PubMed

Sudo, Daisuke; Doutake, Youichi; Yokota, Hidenori; Watanabe, Eiju

2018-05-12

Stuttering occurs in approximately 5% of all children and 1% of adults. One type, neurogenic stuttering, is usually attributable to strokes or other structural damages to the brain areas that are responsible for language fluency. Here, we present the first case of neurogenic stuttering caused by a brain abscess. The patient was a 60-year-old man admitted for a seizure and administered an anticonvulsant, after which he began stuttering. MRI revealed a brain abscess in the left frontal lobe that extended to the dorsolateral prefrontal cortex (BA (Brodmann's area) 9 and 46), frontal eye field (BA 8) and premotor cortex and supplementary motor area (BA 6). After neurosurgical drainage and antibiotic treatment, the symptoms had resolved. This case is unique in that the therapeutic effects and localisation of the cause of stuttering were rapidly identified, allowing for a more accurate description of the neural circuitry related to stuttering. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Modulation of sibutramine-induced increases in extracellular noradrenaline concentration in rat frontal cortex and hypothalamus by α2-adrenoceptors

PubMed Central

Wortley, K E; Heal, D J; Stanford, S C

1999-01-01

The effects of sibutramine (0.25–10 mg kg−1 i.p.) on extracellular noradrenaline concentration in the frontal cortex and hypothalamus of freely-moving rats were investigated using microdialysis. The role of presynaptic α2-adrenoceptors in modulating the effects of sibutramine in these brain areas was also determined.Sibutramine induced an increase in extracellular noradrenaline concentration, the magnitude of which paralleled dose, in both brain areas. In the cortex, this increase was gradual and sustained, whereas in the hypothalamus it was more rapid and of shorter duration.In both the cortex and hypothalamus, pretreatment of rats with the α2-adrenoceptor antagonist RX821002 (3 mg kg−1 i.p.) potentiated increases in the accumulation of extracellular noradrenaline induced by sibutramine (10 mg kg−1 i.p.), by 7 and 10 fold respectively. RX821002 also reduced the latency of sibutramine to reach its maximum effect in the cortex, but not in the hypothalamus.Infusion of RX821002 (1 μM) via the probe increased the accumulation of extracellular noradrenaline induced by sibutramine (10 mg kg−1 i.p.) in both brain areas. In the hypothalamus, the effects of RX821002 on the accumulation of noradrenaline induced by sibutramine were 2 fold greater than those in the cortex.These findings support evidence that sibutramine inhibits the reuptake of noradrenaline in vivo, but that the accumulation of extracellular noradrenaline is limited by noradrenergic activation of presynaptic α2-adrenoceptors. Furthermore, the data suggest that terminal α2-adrenoceptors in the hypothalamus exert a greater inhibitory effect over the control of extracellular noradrenaline accumulation than do those in the cortex. PMID:10516646

Early growth hormone (GH) treatment promotes relevant motor functional improvement after severe frontal cortex lesion in adult rats.

PubMed

Heredia, Margarita; Fuente, A; Criado, J; Yajeya, J; Devesa, J; Riolobos, A S

2013-06-15

A number of studies, in animals and humans, describe the positive effects of the growth hormone (GH) treatment combined with rehabilitation on brain reparation after brain injury. We examined the effect of GH treatment and rehabilitation in adult rats with severe frontal motor cortex ablation. Thirty-five male rats were trained in the paw-reaching-for-food task and the preferred forelimb was recorded. Under anesthesia, the motor cortex contralateral to the preferred forelimb was aspirated or sham-operated. Animals were then treated with GH (0.15 mg/kg/day, s.c) or vehicle during 5 days, commencing immediately or 6 days post-lesion. Rehabilitation was applied at short- and long-term after GH treatment. Behavioral data were analized by ANOVA following Bonferroni post hoc test. After sacrifice, immunohistochemical detection of glial fibrillary acid protein (GFAP) and nestin were undertaken in the brain of all groups. Animal group treated with GH immediately after the lesion, but not any other group, showed a significant improvement of the motor impairment induced by the motor lesion, and their performances in the motor test were no different from sham-operated controls. GFAP immunolabeling and nestin immunoreactivity were observed in the perilesional area in all injured animals; nestin immunoreactivity was higher in GH-treated injured rats (mainly in animals GH-treated 6 days post-lesion). GFAP immunoreactivity was similar among injured rats. Interestingly, nestin re-expression was detected in the contralateral undamaged motor cortex only in GH-treated injured rats, being higher in animals GH-treated immediately after the lesion than in animals GH-treated 6 days post-lesion. Early GH treatment induces significant recovery of the motor impairment produced by frontal cortical ablation. GH effects include increased neurogenesis for reparation (perilesional area) and for increased brain plasticity (contralateral motor area). Copyright © 2013 Elsevier B.V. All rights reserved.

Brain activation during dual-task processing is associated with cardiorespiratory fitness and performance in older adults

PubMed Central

Wong, Chelsea N.; Chaddock-Heyman, Laura; Voss, Michelle W.; Burzynska, Agnieszka Z.; Basak, Chandramallika; Erickson, Kirk I.; Prakash, Ruchika S.; Szabo-Reed, Amanda N.; Phillips, Siobhan M.; Wojcicki, Thomas; Mailey, Emily L.; McAuley, Edward; Kramer, Arthur F.

2015-01-01

Higher cardiorespiratory fitness is associated with better cognitive performance and enhanced brain activation. Yet, the extent to which cardiorespiratory fitness-related brain activation is associated with better cognitive performance is not well understood. In this cross-sectional study, we examined whether the association between cardiorespiratory fitness and executive function was mediated by greater prefrontal cortex activation in healthy older adults. Brain activation was measured during dual-task performance with functional magnetic resonance imaging in a sample of 128 healthy older adults (59–80 years). Higher cardiorespiratory fitness was associated with greater activation during dual-task processing in several brain areas including the anterior cingulate and supplementary motor cortex (ACC/SMA), thalamus and basal ganglia, right motor/somatosensory cortex and middle frontal gyrus, and left somatosensory cortex, controlling for age, sex, education, and gray matter volume. Of these regions, greater ACC/SMA activation mediated the association between cardiorespiratory fitness and dual-task performance. We provide novel evidence that cardiorespiratory fitness may support cognitive performance by facilitating brain activation in a core region critical for executive function. PMID:26321949

Cognitive and psychopathology correlates of brain white/grey matter structure in severely psychotic schizophrenic inpatients.

PubMed

Banaj, Nerisa; Piras, Federica; Piras, Fabrizio; Ciullo, Valentina; Iorio, Mariangela; Battaglia, Claudia; Pantoli, Donatella; Ducci, Giuseppe; Spalletta, Gianfranco

2018-06-01

The brain structural correlates of cognitive and psychopathological symptoms within the active phase in severely psychotic schizophrenic inpatients have been rarely investigated. Twenty-eight inpatients with a DSM-5 diagnosis of Schizophrenia (SZ), admitted for acute psychotic decompensation, were assessed through a comprehensive neuropsychological and psychopathological battery. All patients underwent a high-resolution T1-weighted magnetic resonance imaging investigation. Increased psychotic severity was related to reduced grey matter volumes in the medial portion of the right superior frontal cortex, the superior orbitofrontal cortex bilaterally and to white matter volume reduction in the medial portion of the left superior frontal area. Immediate verbal memory performance was related to left insula and inferior parietal cortex volume, while long-term visuo-spatial memory was related to grey matter volume of the right middle temporal cortex, and the right (lobule VII, CRUS1) and left (lobule VI) cerebellum. Moreover, psychotic severity correlated with cognitive inflexibility and negative symptom severity was related to visuo-spatial processing and reasoning disturbances. These findings indicate that a disruption of the cortical-subcortical-cerebellar circuit, and distorted memory function contribute to the development and maintenance of psychotic exacerbation.

Reward, salience, and attentional networks are activated by religious experience in devout Mormons

PubMed Central

Ferguson, Michael A.; Nielsen, Jared A.; King, Jace B.; Dai, Li; Giangrasso, Danielle M.; Holman, Rachel; Korenberg, Julie R.; Anderson, Jeffrey S.

2017-01-01

High-level cognitive and emotional experience arises from brain activity, but the specific brain substrates for religious and spiritual euphoria remain unclear. We demonstrate using functional magnetic resonance imaging scans in 19 devout Mormons that a recognizable feeling central to their devotional practice was reproducibly associated with activation in nucleus accumbens, ventromedial prefrontal cortex, and frontal attentional regions. Nucleus accumbens activation preceded peak spiritual feelings by 1–3 s and was replicated in four separate tasks. Attentional activation in the anterior cingulate and frontal eye fields was greater in the right hemisphere. The association of abstract ideas and brain reward circuitry may interact with frontal attentional and emotive salience processing, suggesting a mechanism whereby doctrinal concepts may come to be intrinsically rewarding and motivate behavior in religious individuals. PMID:27834117

Synchronizing theta oscillations with direct-current stimulation strengthens adaptive control in the human brain.

PubMed

Reinhart, Robert M G; Zhu, Julia; Park, Sohee; Woodman, Geoffrey F

2015-07-28

Executive control and flexible adjustment of behavior following errors are essential to adaptive functioning. Loss of adaptive control may be a biomarker of a wide range of neuropsychiatric disorders, particularly in the schizophrenia spectrum. Here, we provide support for the view that oscillatory activity in the frontal cortex underlies adaptive adjustments in cognitive processing following errors. Compared with healthy subjects, patients with schizophrenia exhibited low frequency oscillations with abnormal temporal structure and an absence of synchrony over medial-frontal and lateral-prefrontal cortex following errors. To demonstrate that these abnormal oscillations were the origin of the impaired adaptive control in patients with schizophrenia, we applied noninvasive dc electrical stimulation over the medial-frontal cortex. This noninvasive stimulation descrambled the phase of the low-frequency neural oscillations that synchronize activity across cortical regions. Following stimulation, the behavioral index of adaptive control was improved such that patients were indistinguishable from healthy control subjects. These results provide unique causal evidence for theories of executive control and cortical dysconnectivity in schizophrenia.

Exposure to GSM 900 MHz electromagnetic fields affects cerebral cytochrome c oxidase activity.

PubMed

Ammari, Mohamed; Lecomte, Anthony; Sakly, Mohsen; Abdelmelek, Hafedh; de-Seze, René

2008-08-19

The world-wide and rapidly growing use of mobile phones has raised serious concerns about the biological and health-related effects of radio frequency (RF) radiation, particularly concerns about the effects of RFs upon the nervous system. The goal of this study was conducted to measure cytochrome oxidase (CO) levels using histochemical methods in order to evaluate regional brain metabolic activity in rat brain after exposure to a GSM 900 MHz signal for 45 min/day at a brain-averaged specific absorption rate (SAR) of 1.5 W/Kg or for 15 min/day at a SAR of 6 W/Kg over seven days. Compared to the sham and control cage groups, rats exposed to a GSM signal at 6 W/Kg showed decreased CO activity in some areas of the prefrontal and frontal cortex (infralimbic cortex, prelimbic cortex, primary motor cortex, secondary motor cortex, anterior cingulate cortex areas 1 and 2 (Cg1 and Cg2)), the septum (dorsal and ventral parts of the lateral septal nucleus), the hippocampus (dorsal field CA1, CA2 and CA3 of the hippocampus and dental gyrus) and the posterior cortex (retrosplenial agranular cortex, primary and secondary visual cortex, perirhinal cortex and lateral entorhinal cortex). However, the exposure to GSM at 1.5 W/Kg did not affect brain activity. Our results indicate that 6 W/Kg GSM 900 MHz microwaves may affect brain metabolism and neuronal activity in rats.

Inactivation of Primate Prefrontal Cortex Impairs Auditory and Audiovisual Working Memory.

PubMed

Plakke, Bethany; Hwang, Jaewon; Romanski, Lizabeth M

2015-07-01

The prefrontal cortex is associated with cognitive functions that include planning, reasoning, decision-making, working memory, and communication. Neurophysiology and neuropsychology studies have established that dorsolateral prefrontal cortex is essential in spatial working memory while the ventral frontal lobe processes language and communication signals. Single-unit recordings in nonhuman primates has shown that ventral prefrontal (VLPFC) neurons integrate face and vocal information and are active during audiovisual working memory. However, whether VLPFC is essential in remembering face and voice information is unknown. We therefore trained nonhuman primates in an audiovisual working memory paradigm using naturalistic face-vocalization movies as memoranda. We inactivated VLPFC, with reversible cortical cooling, and examined performance when faces, vocalizations or both faces and vocalization had to be remembered. We found that VLPFC inactivation impaired subjects' performance in audiovisual and auditory-alone versions of the task. In contrast, VLPFC inactivation did not disrupt visual working memory. Our studies demonstrate the importance of VLPFC in auditory and audiovisual working memory for social stimuli but suggest a different role for VLPFC in unimodal visual processing. The ventral frontal lobe, or inferior frontal gyrus, plays an important role in audiovisual communication in the human brain. Studies with nonhuman primates have found that neurons within ventral prefrontal cortex (VLPFC) encode both faces and vocalizations and that VLPFC is active when animals need to remember these social stimuli. In the present study, we temporarily inactivated VLPFC by cooling the cortex while nonhuman primates performed a working memory task. This impaired the ability of subjects to remember a face and vocalization pair or just the vocalization alone. Our work highlights the importance of the primate VLPFC in the processing of faces and vocalizations in a manner that is similar to the inferior frontal gyrus in the human brain. Copyright © 2015 the authors 0270-6474/15/359666-10$15.00/0.

NORADRENERGIC CONTROL OF CORTICO-STRIATO-THALAMIC AND MESOLIMBIC CROSS-STRUCTURAL SYNCHRONY

PubMed Central

Dzirasa, Kafui; Phillips, H. Westley; Sotnikova, Tatyana D.; Salahpour, Ali; Kumar, Sunil; Gainetdinov, Raul R.; Caron, Marc G.; Nicolelis, Miguel A. L.

2010-01-01

While normal dopaminergic tone has been shown to be essential for the induction of cortico-striatal and mesolimbic theta oscillatory activity, the influence of norepinephrine on these brain networks remains relatively unknown. To address this question, we simultaneously recorded local field potentials (LFPs) and single neuron activity across ten interconnected brain areas (ventral striatum, frontal association cortex hippocampus, primary motor cortex, orbital frontal cortex, prelimbic cortex, dorsal lateral striatum, medial dorsal nucleus of thalamus, substantia nigra pars reticularis, and ventral tegmental area) in a combined genetically and pharmacologically induced mouse model of hyponoradrenergia. Our results show that norepinephrine (NE) depletion induces a novel state in male mice characterized by a profound disruption of coherence across multiple cortico-striatal circuits, and an increase in mesolimbic cross-structural coherence. Moreover, this brain state is accompanied by a complex behavioral phenotype consisting of transient hyperactivity, stereotypic behaviors, and an acute twelve-fold increase in grooming. Notably, treatment with a norepinephrine precursors (L-DOPA 100mg/kg or L-DOPS 5mg/kg), or a selective serotonin reuptake inhibitor (fluoxetine 20mg/kg) attenuates the abnormal behaviors and selectively reverses the circuit changes observed in NE depleted mice. Together, our results demonstrate that norepinephrine modulates the dynamic tuning of coherence across cortico-striatal-thalamic circuits, and they suggest that changes in coherence across these circuits mediate the abnormal generation of hyperactivity and repetitive behaviors. PMID:20445065

Noradrenergic control of cortico-striato-thalamic and mesolimbic cross-structural synchrony.

PubMed

Dzirasa, Kafui; Phillips, H Westley; Sotnikova, Tatyana D; Salahpour, Ali; Kumar, Sunil; Gainetdinov, Raul R; Caron, Marc G; Nicolelis, Miguel A L

2010-05-05

Although normal dopaminergic tone has been shown to be essential for the induction of cortico-striatal and mesolimbic theta oscillatory activity, the influence of norepinephrine on these brain networks remains relatively unknown. To address this question, we simultaneously recorded local field potentials and single-neuron activity across 10 interconnected brain areas (ventral striatum, frontal association cortex, hippocampus, primary motor cortex, orbital frontal cortex, prelimbic cortex, dorsal lateral striatum, medial dorsal nucleus of thalamus, substantia nigra pars reticularis, and ventral tegmental area) in a combined genetically and pharmacologically induced mouse model of hyponoradrenergia. Our results show that norepinephrine (NE) depletion induces a novel state in male mice characterized by a profound disruption of coherence across multiple cortico-striatal circuits and an increase in mesolimbic cross-structural coherence. Moreover, this brain state is accompanied by a complex behavioral phenotype consisting of transient hyperactivity, stereotypic behaviors, and an acute 12-fold increase in grooming. Notably, treatment with a norepinephrine precursors (l-3,4-dihydroxyphenylalanine at 100 mg/kg or l-threo-dihydroxyphenylserine at 5 mg/kg) or a selective serotonin reuptake inhibitor (fluoxetine at 20 mg/kg) attenuates the abnormal behaviors and selectively reverses the circuit changes observed in NE-depleted mice. Together, our results demonstrate that norepinephrine modulates the dynamic tuning of coherence across cortico-striato-thalamic circuits, and they suggest that changes in coherence across these circuits mediate the abnormal generation of hyperactivity and repetitive behaviors.

Witnessing hateful people in pain modulates brain activity in regions associated with physical pain and reward

PubMed Central

Fox, Glenn R.; Sobhani, Mona; Aziz-Zadeh, Lisa

2013-01-01

How does witnessing a hateful person in pain compare to witnessing a likable person in pain? The current study compared the brain bases for how we perceive likable people in pain with those of viewing hateful people in pain. While social bonds are built through sharing the plight and pain of others in the name of empathy, viewing a hateful person in pain also has many potential ramifications. In this functional Magnetic Resonance Imaging (fMRI) study, Caucasian Jewish male participants viewed videos of (1) disliked, hateful, anti-Semitic individuals, and (2) liked, non-hateful, tolerant individuals in pain. The results showed that, compared with viewing liked people, viewing hateful people in pain elicited increased responses in regions associated with observation of physical pain (the insular cortex, the anterior cingulate cortex (ACC), and the somatosensory cortex), reward processing (the striatum), and frontal regions associated with emotion regulation. Functional connectivity analyses revealed connections between seed regions in the left ACC and right insular cortex with reward regions, the amygdala, and frontal regions associated with emotion regulation. These data indicate that regions of the brain active while viewing someone in pain may be more active in response to the danger or threat posed by witnessing the pain of a hateful individual more so than the desire to empathize with a likable person's pain. PMID:24167496

An Evo-Devo Approach to Thyroid Hormones in Cerebral and Cerebellar Cortical Development: Etiological Implications for Autism

PubMed Central

Berbel, Pere; Navarro, Daniela; Román, Gustavo C.

2014-01-01

The morphological alterations of cortical lamination observed in mouse models of developmental hypothyroidism prompted the recognition that these experimental changes resembled the brain lesions of children with autism; this led to recent studies showing that maternal thyroid hormone deficiency increases fourfold the risk of autism spectrum disorders (ASD), offering for the first time the possibility of prevention of some forms of ASD. For ethical reasons, the role of thyroid hormones on brain development is currently studied using animal models, usually mice and rats. Although mammals have in common many basic developmental principles regulating brain development, as well as fundamental basic mechanisms that are controlled by similar metabolic pathway activated genes, there are also important differences. For instance, the rodent cerebral cortex is basically a primary cortex, whereas the primary sensory areas in humans account for a very small surface in the cerebral cortex when compared to the associative and frontal areas that are more extensive. Associative and frontal areas in humans are involved in many neurological disorders, including ASD, attention deficit-hyperactive disorder, and dyslexia, among others. Therefore, an evo-devo approach to neocortical evolution among species is fundamental to understand not only the role of thyroid hormones and environmental thyroid disruptors on evolution, development, and organization of the cerebral cortex in mammals but also their role in neurological diseases associated to thyroid dysfunction. PMID:25250016

Reduced frontal cortex thickness and cortical volume associated with pathological narcissism.

PubMed

Mao, Yu; Sang, Na; Wang, Yongchao; Hou, Xin; Huang, Hui; Wei, Dongtao; Zhang, Jinfu; Qiu, Jiang

2016-07-22

Pathological narcissism is often characterized by arrogant behavior, a lack of empathy, and willingness to exploit other individuals. Generally, individuals with high levels of narcissism are more likely to suffer mental disorders. However, the brain structural basis of individual pathological narcissism trait among healthy people has not yet been investigated with surface-based morphometry. Thus, in this study, we investigated the relationship between cortical thickness (CT), cortical volume (CV), and individual pathological narcissism in a large healthy sample of 176 college students. Multiple regression was used to analyze the correlation between regional CT, CV, and the total Pathological Narcissism Inventory (PNI) score, adjusting for age, sex, and total intracranial volume. The results showed that the PNI score was significantly negatively associated with CT and CV in the right dorsolateral prefrontal cortex (DLPFC, key region of the central executive network, CEN), which might be associated with impaired emotion regulation processes. Furthermore, the PNI score showed significant negative associations with CV in the right postcentral gyrus, left medial prefrontal cortex (MPFC), and the CT in the right inferior frontal cortex (IFG, overlap with social brain network), which may be related to impairments in social cognition. Together, these findings suggest a unique structural basis for individual differences in pathological narcissism, distributed across different gray matter regions of the social brain network and CEN. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Multiple brain networks for visual self-recognition with different sensitivity for motion and body part.

PubMed

Sugiura, Motoaki; Sassa, Yuko; Jeong, Hyeonjeong; Miura, Naoki; Akitsuki, Yuko; Horie, Kaoru; Sato, Shigeru; Kawashima, Ryuta

2006-10-01

Multiple brain networks may support visual self-recognition. It has been hypothesized that the left ventral occipito-temporal cortex processes one's own face as a symbol, and the right parieto-frontal network processes self-image in association with motion-action contingency. Using functional magnetic resonance imaging, we first tested these hypotheses based on the prediction that these networks preferentially respond to a static self-face and to moving one's whole body, respectively. Brain activation specifically related to self-image during familiarity judgment was compared across four stimulus conditions comprising a two factorial design: factor Motion contrasted picture (Picture) and movie (Movie), and factor Body part a face (Face) and whole body (Body). Second, we attempted to segregate self-specific networks using a principal component analysis (PCA), assuming an independent pattern of inter-subject variability in activation over the four stimulus conditions in each network. The bilateral ventral occipito-temporal and the right parietal and frontal cortices exhibited self-specific activation. The left ventral occipito-temporal cortex exhibited greater self-specific activation for Face than for Body, in Picture, consistent with the prediction for this region. The activation profiles of the right parietal and frontal cortices did not show preference for Movie Body predicted by the assumed roles of these regions. The PCA extracted two cortical networks, one with its peaks in the right posterior, and another in frontal cortices; their possible roles in visuo-spatial and conceptual self-representations, respectively, were suggested by previous findings. The results thus supported and provided evidence of multiple brain networks for visual self-recognition.

An Herbal Nasal Drop Enhanced Frontal and Anterior Cingulate Cortex Activity

PubMed Central

Chan, Agnes S.; Cheung, Mei-chun; Sze, Sophia L.; Leung, Winnie W.; Shi, Dejian

2011-01-01

The present study examined the neuro-electrophysiological activity of the brain associated with the application of a herbal remedy developed by a Shaolin monk based upon the Chan healing principle of clearing the orifices (i.e., the nasal cavities). A repeated-measures design was used. Fourteen normal adults were administered herbal remedy and saline solution intranasally on separate sessions. Two intervals of eyes-closed resting EEG data were obtained individually before and after each administration. Results showed that only the herbal remedy but not the saline solution induced elevation in cordance, an index correlated with cerebral perfusion, in the anterior brain region. In addition, the activity of the anterior cingulate cortex (ACC), as examined by the LORETA analysis, was also increased after the application of the herbal remedy but not saline solution. The present study provided some preliminary evidence suggesting that the herbal nasal drop enhanced the activity of the frontal lobe and ACC. Implications for the potential clinical application of the herbal remedy to treat patients with frontal lobe disorders were discussed. PMID:19996154

Damage to Left Frontal Regulatory Circuits Produces Greater Positive Emotional Reactivity in Frontotemporal Dementia

PubMed Central

Sturm, Virginia E.; Yokoyama, Jennifer S.; Eckart, Janet A.; Zakrzewski, Jessica; Rosen, Howard J.; Miller, Bruce L.; Seeley, William W.; Levenson, Robert W.

2015-01-01

Positive emotions foster social relationships and motivate thought and action. Dysregulation of positive emotion may give rise to debilitating clinical symptomatology such as mania, risk-taking, and disinhibition. Neuroanatomically, there is extensive evidence that the left hemisphere of the brain, and the left frontal lobe in particular, plays an important role in positive emotion generation. Although prior studies have found that left frontal injury decreases positive emotion, it is not clear whether selective damage to left frontal emotion regulatory systems can actually increase positive emotion. We measured happiness reactivity in 96 patients with frontotemporal dementia, a neurodegenerative disease that targets emotion-relevant neural systems and causes alterations in positive emotion (i.e., euphoria and jocularity), and in 34 healthy controls. Participants watched a film clip designed to elicit happiness and a comparison film clip designed to elicit sadness while their facial behavior, physiological reactivity, and self-reported emotional experience were monitored. Whole-brain voxel-based morphometry analyses revealed that atrophy in predominantly left hemisphere fronto-striatal emotion regulation systems including left ventrolateral prefrontal cortex, orbitofrontal cortex, anterior insula, and striatum (pFWE < .05) was associated with greater happiness facial behavior during the film. Atrophy in left anterior insula and bilateral frontopolar cortex was also associated with higher cardiovascular reactivity (i.e., heart rate and blood pressure) but not self-reported positive emotional experience during the happy film (p< .005, uncorrected). No regions emerged as being associated with greater sadness reactivity, which suggests that left-lateralized fronto-striatal atrophy is selectively associated with happiness dysregulation. Whereas previous models have proposed that left frontal injury decreases positive emotional responding, we argue that selective disruption of left hemisphere emotion regulating systems can impair the ability to suppress positive emotions such as happiness. PMID:25461707

The perinatal effects of maternal caffeine intake on fetal and neonatal brain levels of testosterone, estradiol, and dihydrotestosterone in rats.

PubMed

Karaismailoglu, S; Tuncer, M; Bayrak, S; Erdogan, G; Ergun, E L; Erdem, A

2017-08-01

Testosterone, estradiol, and dihydrotestosterone are the main sex steroid hormones responsible for the organization and sexual differentiation of brain structures during early development. The hypothalamo-pituitary-adrenocortical axis, adrenal cells, and gonads play a key role in the production of sex steroids and express adenosine receptors. Caffeine is a non-selective adenosine antagonist; therefore, it can modulate metabolic pathways in these tissues. Besides, the proportion of pregnant women that consume caffeine is ∼60%. That is why the relationship between maternal caffeine consumption and fetal development is important. Therefore, we aimed to investigate this modulatory effect of maternal caffeine consumption on sex steroids in the fetal and neonatal brain tissues. Pregnant rats were treated with a low (0.3 g/L) or high (0.8 g/L) dose of caffeine in their drinking water during pregnancy and lactation. The testosterone, estradiol, and dihydrotestosterone levels in the frontal cortex and hypothalamus were measured using radioimmunoassay at embryonic day 19 (E19), birth (PN0), and postnatal day 4 (PN4). The administration of low-dose caffeine increased the body weight in PN4 male and female rats and anogenital index in PN4 males. The administration of high-dose caffeine decreased the adrenal weight in E19 male rats and increased testosterone levels in the frontal cortex of E19 female rats and the hypothalamus of PN0 male rats. Maternal caffeine intake during pregnancy affects sex steroid levels in the frontal cortex and hypothalamus of the offspring. This concentration changes of the sex steroids in the brain may influence behavioral and neuroendocrine functions at some point in adult life.

Out-of-synchrony speech entrainment in developmental dyslexia.

PubMed

Molinaro, Nicola; Lizarazu, Mikel; Lallier, Marie; Bourguignon, Mathieu; Carreiras, Manuel

2016-08-01

Developmental dyslexia is a reading disorder often characterized by reduced awareness of speech units. Whether the neural source of this phonological disorder in dyslexic readers results from the malfunctioning of the primary auditory system or damaged feedback communication between higher-order phonological regions (i.e., left inferior frontal regions) and the auditory cortex is still under dispute. Here we recorded magnetoencephalographic (MEG) signals from 20 dyslexic readers and 20 age-matched controls while they were listening to ∼10-s-long spoken sentences. Compared to controls, dyslexic readers had (1) an impaired neural entrainment to speech in the delta band (0.5-1 Hz); (2) a reduced delta synchronization in both the right auditory cortex and the left inferior frontal gyrus; and (3) an impaired feedforward functional coupling between neural oscillations in the right auditory cortex and the left inferior frontal regions. This shows that during speech listening, individuals with developmental dyslexia present reduced neural synchrony to low-frequency speech oscillations in primary auditory regions that hinders higher-order speech processing steps. The present findings, thus, strengthen proposals assuming that improper low-frequency acoustic entrainment affects speech sampling. This low speech-brain synchronization has the strong potential to cause severe consequences for both phonological and reading skills. Interestingly, the reduced speech-brain synchronization in dyslexic readers compared to normal readers (and its higher-order consequences across the speech processing network) appears preserved through the development from childhood to adulthood. Thus, the evaluation of speech-brain synchronization could possibly serve as a diagnostic tool for early detection of children at risk of dyslexia. Hum Brain Mapp 37:2767-2783, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Patterns of brain activity during a semantic task differentiate normal aging from early Alzheimer's disease.

PubMed

McGeown, William Jonathan; Shanks, Michael Fraser; Forbes-McKay, Katrina Elaine; Venneri, Annalena

2009-09-30

In a study of the effects of normal and pathological aging on semantic-related brain activity, 29 patients with Alzheimer's disease (AD) and 19 controls subjects (10 young and 9 older controls) performed a version of the Pyramids and Palm Trees Test that had been adapted for use during functional magnetic resonance imaging (fMRI). Young and older controls activated the left inferior and middle frontal gyri, precuneus and superior parietal lobule. Right frontal and left temporal cortices were activated only in the young. The AD group activated only the left prefrontal and cingulate cortex. Separate analyses of high- and low-performing AD subgroups showed a similar pattern of activation in the left frontal lobe, although activiation was more widespread in low performers. High performers significantly deactivated anterior midline frontal structures, however, while low performers did not. When the older adult and AD groups were combined, there was a significant positive correlation between left frontal and parietal activation and Mini-Mental State Examination (MMSE) score (covarying for age), suggesting a disease effect. A significant negative correlation between activation in the left temporal cortex and age (covarying for MMSE score) reflected a possible age effect. These differential effects suggest that semantic activation paradigms might aid diagnosis in those cases for whom conventional assessments lack the necessary sensitivity to detect subtle changes.

Heart type fatty acid binding protein (H-FABP) is decreased in brains of patients with Down syndrome and Alzheimer's disease.

PubMed

Cheon, M S; Kim, S H; Fountoulakis, M; Lubec, G

2003-01-01

Fatty acid binding proteins (FABPs) are thought to play a role in the binding, targeting and transport of long-chain fatty acids, and at least three types of FABPs are found in human brain; heart type (H)-FABP, brain type (B)-FABP and epidermal type (E)-FABP. Although all three FABPs could be involved in normal brain function in prenatal and postnatal life, a neurobiological role of FABPs in neurodegenerative diseases has not been reported yet. These made us evaluate the protein levels of FABPs in brains from patients with Down syndrome (DS) and Alzheimer's disease (AD) and fetal cerebral cortex with DS using two-dimensional (2-D) gel electrophoresis with subsequent matrix-assisted laser desorption ionization mass spectroscopy (MALDI-MS) identification and specific software for quantification of proteins. In adult brain, B-FABP was significantly increased in occipital cortex of DS, and H-FABP was significantly decreased in DS (frontal, occipital and parietal cortices) and AD (frontal, temporal, occipital and parietal cortices). In fetal brain, B-FABP and epidermal E-FABP levels were comparable in controls and DS. We conclude that aberrant expression of FABPs, especially H-FABP may alter membrane fluidity and signal transduction, and consequently could be involved in cellular dysfunction in neurodegenerative disorders.

Cortical thickness and folding deficits in conduct-disordered adolescents

PubMed Central

Hyatt, Christopher J.; Haney-Caron, Emily; Stevens, Michael C.

2012-01-01

Background Studies of pediatric conduct disorder (CD) have described frontal and temporal lobe structural abnormalities that parallel findings in antisocial adults. The purpose of this study was to examine previously unexplored cortical thickness and folding as markers for brain abnormalities in “pure CD”-diagnosed adolescents. Based on current fronto-temporal theories, we hypothesized that CD youth would have thinner cortex or less cortical folding in temporal and frontal lobes than control subjects. Methods We obtained T1-weighted brain structure images from n=24 control and n=19 CD participants aged 12–18 years, matched by overall gender and age. We measured group differences in cortical thickness and local gyrification index (regional cortical folding measure) using surface-based morphometry with clusterwise correction for multiple comparisons. Results CD participants, when compared with controls, showed both reduced cortical thickness and folding. Thinner cortex was located primarily in posterior brain regions, including left superior temporal and parietal lobes, temporoparietal junction and paracentral lobule, right superior temporal and parietal lobes, temporoparietal junction and precuneus. Folding deficits were located mainly in anterior brain regions and included left insula, ventro- and dorsomedial prefrontal, anterior cingulate and orbitofrontal cortices, temporal lobe, right superior frontal and parietal lobes and paracentral lobule. Conclusions Our findings generally agree with previous CD volumetric studies, but here show the unique contributions of cortical thickness and folding to gray matter reductions in pure CD in different brain regions. PMID:22209639

Regional homogeneity of spontaneous brain activity in adult patients with obsessive-compulsive disorder before and after cognitive behavioural therapy.

PubMed

Yang, Xiang-Yun; Sun, Jing; Luo, Jia; Zhong, Zhao-Xi; Li, Ping; Yao, Shu-Min; Xiong, Hong-Fang; Huang, Fang-Fang; Li, Zhan-Jiang

2015-12-01

Cognitive behavioural therapy (CBT) is an effective treatment for obsessive-compulsive disorder (OCD). Several neuroimaging studies have explored alterations of brain function in OCD patients as they performed tasks after CBT. However, the effects of CBT on the neural activityin OCD during rest remain unknown. Therefore, we investigated changes in regional homogeneity (ReHo) in OCD patients before and after CBT. Twenty-two OCD patients and 22 well-matched healthy controls participated in the resting-state functional magnetic resonance imaging scans. We compared differences in ReHo between the OCD and control groups before treatment and investigated the changes of ReHo in 17 OCD patients who responded to CBT. Compared to healthy controls, OCD patients exhibited higher ReHo in the right orbitofrontal cortex (OFC), bilateral middle frontal cortex, right precuneus, left cerebellum, and vermis, as well as lower ReHo in the bilateral caudate, right calcarine, right posterior cingulate cortex, and right middle temporal cortex. Along with the clinical improvement in OCD patients after CBT, we found decreased ReHo in the right OFC, bilateral middle frontal cortex, left cerebellum and vermis, and increased ReHo in the left caudate. Improvement of OCD symptoms was significantly correlated with the changed ReHo in the right OFC and left cerebellum. Although these findings are preliminary and need to be replicated in larger samples, they indicate the presence of abnormal spontaneous brain activity of the prefrontal-striatal-cerebellar circuit in OCD patients, and provide evidence that CBT can selectively modulate the spontaneous brain activity of this circuit in OCD patients. Copyright © 2015 Elsevier B.V. All rights reserved.

Alterations in regional homogeneity of resting-state brain activity in patients with major depressive disorder screening positive on the 32-item hypomania checklist (HCL-32).

PubMed

Yang, Haichen; Li, Linling; Peng, Hongjun; Liu, Tiebang; Young, Allan H; Angst, Jules; Ye, Rong; Rong, Han; Ji, Erni; Qiu, Yunhai; Li, Lingjiang

2016-10-01

Bipolar disorder (BD) is difficult to diagnose in the early stages of the illness, with the most frequent misdiagnosis being major depressive disorder (MDD). We aimed to use a regional homogeneity (ReHo) approach with resting-state functional magnetic resonance imaging (rs-fMRI) to investigate the features of spontaneous brain activity in MDD patients screening positive on the 32-item Hypomania Checklist (HCL-32). Nineteen MDD patients screening positive (HCL-32(+); 9 males; 24.9±5.7 years) and 18 patients screening negative (HCL-32(-); 9 males; 27.1±6.7 years), together with 24 healthy controls (HC; 11 males; 26.4±3.9 years) were studied. ReHo maps were compared and an receiver operating characteristic (ROC) analysis was conducted to confirm the utility of the identified ReHo differences in classifying the patients. The MDD versus HC showed different ReHo in many brain areas, especially in the frontal and parietal cortex. The HCL-32(+) versus HCL-32(-) showed significant increase of ReHo in the right medial superior frontal cortex, left inferior parietal cortex and middle/inferior temporal cortex, and decrease of ReHo in the left postcentral cortex and cerebellum. ROC analysis showed good sensitivity and specificity for distinguishing these two subgroups of MDD. Recruited patients were all on antidepressants and standard mania rating scales were not performed to assess their hypomanic symptoms. The rs-fMRI measurement of ReHo in distributed brain regions may be putative biomarkers which could differentiate subthreshold BD from MDD. Copyright © 2016 Elsevier B.V. All rights reserved.

Glutamine synthetase activity and glutamate uptake in hippocampus and frontal cortex in portal hypertensive rats

PubMed Central

Acosta, Gabriela Beatriz; Fernández, María Alejandra; Roselló, Diego Martín; Tomaro, María Luján; Balestrasse, Karina; Lemberg, Abraham

2009-01-01

AIM: To study glutamine synthetase (GS) activity and glutamate uptake in the hippocampus and frontal cortex (FC) from rats with prehepatic portal vein hypertension. METHODS: Male Wistar rats were divided into sham-operated group and a portal hypertension (PH) group with a regulated stricture of the portal vein. Animals were sacrificed by decapitation 14 d after portal vein stricture. GS activity was determined in the hippocampus and FC. Specific uptake of radiolabeled L-glutamate was studied using synaptosome-enriched fractions that were freshly prepared from both brain areas. RESULTS: We observed that the activity of GS increased in the hippocampus of PH rats, as compared to control animals, and decreased in the FC. A significant decrease in glutamate uptake was found in both brain areas, and was more marked in the hippocampus. The decrease in glutamate uptake might have been caused by a deficient transport function, significantly and persistent increase in this excitatory neurotransmitter activity. CONCLUSION: The presence of moderate ammonia blood levels may add to the toxicity of excitotoxic glutamate in the brain, which causes alterations in brain function. Portal vein stricture that causes portal hypertension modifies the normal function in some brain regions. PMID:19533812

Mismatch negativity results from bilateral asymmetric dipole sources in the frontal and temporal lobes.

PubMed

Jemel, Boutheina; Achenbach, Christiane; Müller, Bernhard W; Röpcke, Bernd; Oades, Robert D

2002-01-01

The event-related potential (ERP) reflecting auditory change detection (mismatch negativity, MMN) registers automatic selective processing of a deviant sound with respect to a working memory template resulting from a series of standard sounds. Controversy remains whether MMN can be generated in the frontal as well as the temporal cortex. Our aim was to see if frontal as well as temporal lobe dipoles could explain MMN recorded after pitch-deviants (Pd-MMN) and duration deviants (Dd-MMN). EEG recordings were taken from 32 sites in 14 healthy subjects during a passive 3-tone oddball presented during a simple visual discrimination and an active auditory discrimination condition. Both conditions were repeated after one month. The Pd-MMN was larger, peaked earlier and correlated better between sessions than the Dd-MMN. Two dipoles in the auditory cortex and two in the frontal lobe (left cingulate and right inferior frontal cortex) were found to be similarly placed for Pd- and Dd-MMN, and were well replicated on retest. This study confirms interactions between activity generated in the frontal and auditory temporal cortices in automatic attention-like processes that resemble initial brain imaging reports of unconscious visual change detection. The lack of interference between sessions shows that the situation is likely to be sensitive to treatment or illness effects on fronto-temporal interactions involving repeated measures.

Propofol attenuates low-frequency fluctuations of resting-state fMRI BOLD signal in the anterior frontal cortex upon loss of consciousness.

PubMed

Liu, Xiaolin; Lauer, Kathryn K; Douglas Ward, B; Roberts, Christopher; Liu, Suyan; Gollapudy, Suneeta; Rohloff, Robert; Gross, William; Chen, Guangyu; Xu, Zhan; Binder, Jeffrey R; Li, Shi-Jiang; Hudetz, Anthony G

2017-02-15

Recent studies indicate that spontaneous low-frequency fluctuations (LFFs) of resting-state functional magnetic resonance imaging (rs-fMRI) blood oxygen level-dependent (BOLD) signals are driven by the slow (<0.1Hz) modulation of ongoing neuronal activity synchronized locally and across remote brain regions. How regional LFFs of the BOLD fMRI signal are altered during anesthetic-induced alteration of consciousness is not well understood. Using rs-fMRI in 15 healthy participants, we show that during administration of propofol to achieve loss of behavioral responsiveness indexing unconsciousness, the fractional amplitude of LFF (fALFF index) was reduced in comparison to wakeful baseline in the anterior frontal regions, temporal pole, hippocampus, parahippocampal gyrus, and amygdala. Such changes were absent in large areas of the motor, parietal, and sensory cortices. During light sedation characterized by the preservation of overt responsiveness and therefore consciousness, fALFF was reduced in the subcortical areas, temporal pole, medial orbital frontal cortex, cingulate cortex, and cerebellum. Between light sedation and deep sedation, fALFF was reduced primarily in the medial and dorsolateral frontal areas. The preferential reduction of LFFs in the anterior frontal regions is consistent with frontal to sensory-motor cortical disconnection and may contribute to the suppression of consciousness during general anesthesia. Copyright © 2016 Elsevier Inc. All rights reserved.

Propofol attenuates low-frequency fluctuations of resting-state fMRI BOLD signal in the anterior frontal cortex upon loss of consciousness

PubMed Central

Liu, Xiaolin; Lauer, Kathryn K.; Ward, B. Douglas; Roberts, Christopher; Liu, Suyan; Gollapudy, Suneeta; Rohloff, Robert; Gross, William; Chen, Guangyu; Xu, Zhan; Binder, Jeffrey R.; Li, Shi-Jiang; Hudetz, Anthony G.

2017-01-01

Recent studies indicate that spontaneous low-frequency fluctuations (LFFs) of resting-state functional magnetic resonance imaging (rs-fMRI) blood oxygen level-dependent (BOLD) signals are driven by the slow (<0.1 Hz) modulation of ongoing neuronal activity synchronized locally and across remote brain regions. How regional LFFs of the BOLD fMRI signal are altered during anesthetic-induced alteration of consciousness is not well understood. Using rs-fMRI in 15 healthy participants, we show that during administration of propofol to achieve loss of behavioral responsiveness indexing unconsciousness, the fractional amplitude of LFF (fALFF index) was reduced in comparison to wakeful baseline in the anterior frontal regions, temporal pole, hippocampus, parahippocampal gyrus, and amygdala. Such changes were absent in large areas of the motor, parietal, and sensory cortices. During light sedation characterized by the preservation of overt responsiveness and therefore consciousness, fALFF was reduced in the subcortical areas, temporal pole, medial orbital frontal cortex, cingulate cortex, and cerebellum. Between light sedation and deep sedation, fALFF was reduced primarily in the medial and dorsolateral frontal areas. The preferential reduction of LFFs in the anterior frontal regions is consistent with frontal to sensory-motor cortical disconnection and may contribute to the suppression of consciousness during general anesthesia. PMID:27993673

Frontal and Parietal Cortices Show Different Spatiotemporal Dynamics across Problem-solving Stages.

PubMed

Tschentscher, Nadja; Hauk, Olaf

2016-08-01

Arithmetic problem-solving can be conceptualized as a multistage process ranging from task encoding over rule and strategy selection to step-wise task execution. Previous fMRI research suggested a frontal-parietal network involved in the execution of complex numerical and nonnumerical tasks, but evidence is lacking on the particular contributions of frontal and parietal cortices across time. In an arithmetic task paradigm, we evaluated individual participants' "retrieval" and "multistep procedural" strategies on a trial-by-trial basis and contrasted those in time-resolved analyses using combined EEG and MEG. Retrieval strategies relied on direct retrieval of arithmetic facts (e.g., 2 + 3 = 5). Procedural strategies required multiple solution steps (e.g., 12 + 23 = 12 + 20 + 3 or 23 + 10 + 2). Evoked source analyses revealed independent activation dynamics within the first second of problem-solving in brain areas previously described as one network, such as the frontal-parietal cognitive control network: The right frontal cortex showed earliest effects of strategy selection for multistep procedural strategies around 300 msec, before parietal cortex activated around 700 msec. In time-frequency source power analyses, memory retrieval and multistep procedural strategies were differentially reflected in theta, alpha, and beta frequencies: Stronger beta and alpha desynchronizations emerged for procedural strategies in right frontal, parietal, and temporal regions as function of executive demands. Arithmetic fact retrieval was reflected in right prefrontal increases in theta power. Our results demonstrate differential brain dynamics within frontal-parietal networks across the time course of a problem-solving process, and analyses of different frequency bands allowed us to disentangle cortical regions supporting the underlying memory and executive functions.

Frontal Gamma-Aminobutyric Acid Concentrations Are Associated With Cognitive Performance in Older Adults.

PubMed

Porges, Eric C; Woods, Adam J; Edden, Richard A E; Puts, Nicolaas A J; Harris, Ashley D; Chen, Huaihou; Garcia, Amanda M; Seider, Talia R; Lamb, Damon G; Williamson, John B; Cohen, Ronald A

2017-01-01

Gamma-aminobutyric acid (GABA), the brain's principal inhibitory neurotransmitter, has been associated with perceptual and attentional functioning. Recent application of magnetic resonance spectroscopy (MRS) provides in vivo evidence for decreasing GABA concentrations during adulthood. It is unclear, however, how age-related decrements in cerebral GABA concentrations contribute to cognitive decline, or whether previously reported declines in cerebral GABA concentrations persist during healthy aging. We hypothesized that participants with higher GABA concentrations in the frontal cortex would exhibit superior cognitive function and that previously reported age-related decreases in cortical GABA concentrations continue into old age. We measured GABA concentrations in frontal and posterior midline cerebral regions using a Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) 1 H-MRS approach in 94 older adults without history or clinical evidence of mild cognitive impairment or dementia (mean age, 73 years). We administered the Montreal Cognitive Assessment to assess cognitive functioning. Greater frontal GABA concentrations were associated with superior cognitive performance. This relation remained significant after controlling for age, years of education, and brain atrophy. GABA concentrations in both frontal and posterior regions decreased as a function of age. These novel findings from a large, healthy, older population indicate that cognitive function is sensitive to cerebral GABA concentrations in the frontal cortex, and GABA concentration in frontal and posterior regions continue to decline in later age. These effects suggest that proton MRS may provide a clinically useful method for the assessment of normal and abnormal age-related cognitive changes and the associated physiological contributors.

Dissociation and Convergence of the Dorsal and Ventral Visual Streams in the Human Prefrontal Cortex

PubMed Central

Takahashi, Emi; Ohki, Kenichi; Kim, Dae-Shik

2012-01-01

Visual information is largely processed through two pathways in the primate brain: an object pathway from the primary visual cortex to the temporal cortex (ventral stream) and a spatial pathway to the parietal cortex (dorsal stream). Whether and to what extent dissociation exists in the human prefrontal cortex (PFC) has long been debated. We examined anatomical connections from functionally defined areas in the temporal and parietal cortices to the PFC, using noninvasive functional and diffusion-weighted magnetic resonance imaging. The right inferior frontal gyrus (IFG) received converging input from both streams, while the right superior frontal gyrus received input only from the dorsal stream. Interstream functional connectivity to the IFG was dynamically recruited only when both object and spatial information were processed. These results suggest that the human PFC receives dissociated and converging visual pathways, and that the right IFG region serves as an integrator of the two types of information. PMID:23063444

Proton magnetic resonance spectroscopy (MRS) in on-line game addiction

PubMed Central

Han, Doug Hyun; Lee, Young Sik; Shi, Xianfeng; Renshaw, Perry F.

2015-01-01

Recent brain imaging studies suggested that both the frontal and temporal cortices are important candidate areas for mediating the symptoms of internet addiction. We hypothesized that deficits of prefrontal and temporal cortical function in patients with on-line game addiction (PGA) would be reflected in decreased levels of N-acetyl aspartate (NAA) and cytosolic, choline containing compound (Cho). Seventy three young PGA and 38 age and sex matched healthy control subjects were recruited in the study. Structural MR and 1H MRS data were acquired using a 3.0 T MRI scanner. Voxels were sequentially placed in right frontal cortex and right medial temporal cortices. In the right frontal cortex, the levels of NAA in PGA were lower than those in healthy controls. In the medial temporal cortex, the levels of Cho in PGA participants were lower than those observed in healthy controls. The Young Internet Addiction Scale (YIAS) scores and perseverative responses in PGA were negatively correlated with the level of NAA in right frontal cortex. The Beck Depressive Inventory (BDI) scores in the PGA cohort were negatively correlated with Cho levels in the right temporal lobe. To the best of our knowledge, this is the first MRS study of individuals with on-line game addiction. Although, the subjects with on-line game addiction in the current study were free from psychiatric co-morbidity, patients with on-line game addiction appear to share characteristics with ADHD and MDD in terms of neurochemical changes in frontal and temporal cortices. PMID:25088284

Altered Resting State Effective Connectivity of Anterior Insula in Depression.

PubMed

Kandilarova, Sevdalina; Stoyanov, Drozdstoy; Kostianev, Stefan; Specht, Karsten

2018-01-01

Depression has been associated with changes in both functional and effective connectivity of large scale brain networks, including the default mode network, executive network, and salience network. However, studies of effective connectivity by means of spectral dynamic causal modeling (spDCM) are still rare and the interaction between the different resting state networks has not been investigated in detail. Thus, we aimed at exploring differences in effective connectivity among eight right hemisphere brain areas-anterior insula, inferior frontal gyrus, middle frontal gyrus (MFG), frontal eye field, anterior cingulate cortex, superior parietal lobe, amygdala, and hippocampus, between a group of healthy controls ( N  = 20) and medicated depressed patients ( N  = 20). We found that patients not only had significantly reduced strength of the connection from the anterior insula to the MFG (i.e., dorsolateral prefrontal cortex) but also a significant connection between the amygdala and the anterior insula. Moreover, depression severity correlated with connectivity of the hippocampal node. In conclusion, the results from this resting state spDCM study support and enrich previous data on the role of the right anterior insula in the pathophysiology of depression. Furthermore, our findings add to the growing evidence of an association between depression severity and disturbances of the hippocampal function in terms of impaired connectivity with other brain regions.

Altered Resting State Effective Connectivity of Anterior Insula in Depression

PubMed Central

Kandilarova, Sevdalina; Stoyanov, Drozdstoy; Kostianev, Stefan; Specht, Karsten

2018-01-01

Depression has been associated with changes in both functional and effective connectivity of large scale brain networks, including the default mode network, executive network, and salience network. However, studies of effective connectivity by means of spectral dynamic causal modeling (spDCM) are still rare and the interaction between the different resting state networks has not been investigated in detail. Thus, we aimed at exploring differences in effective connectivity among eight right hemisphere brain areas—anterior insula, inferior frontal gyrus, middle frontal gyrus (MFG), frontal eye field, anterior cingulate cortex, superior parietal lobe, amygdala, and hippocampus, between a group of healthy controls (N = 20) and medicated depressed patients (N = 20). We found that patients not only had significantly reduced strength of the connection from the anterior insula to the MFG (i.e., dorsolateral prefrontal cortex) but also a significant connection between the amygdala and the anterior insula. Moreover, depression severity correlated with connectivity of the hippocampal node. In conclusion, the results from this resting state spDCM study support and enrich previous data on the role of the right anterior insula in the pathophysiology of depression. Furthermore, our findings add to the growing evidence of an association between depression severity and disturbances of the hippocampal function in terms of impaired connectivity with other brain regions. PMID:29599728

Small gray matter volume in orbitofrontal cortex in Prader-Willi syndrome: a voxel-based MRI study.

PubMed

Ogura, Kaeko; Fujii, Toshikatsu; Abe, Nobuhito; Hosokai, Yoshiyuki; Shinohara, Mayumi; Takahashi, Shoki; Mori, Etsuro

2011-07-01

Prader-Willi syndrome (PWS) is a genetically determined neurodevelopmental disorder presenting with behavioral symptoms including hyperphagia, disinhibition, and compulsive behavior. The behavioral problems in individuals with PWS are strikingly similar to those in patients with frontal pathologies, particularly those affecting the orbitofrontal cortex (OFC). However, neuroanatomical abnormalities in the frontal lobe have not been established in PWS. The aim of this study was to look, using volumetric analysis, for morphological changes in the frontal lobe, especially the OFC, of the brains of individuals with PWS. Twelve adults with PWS and 13 age- and gender-matched control subjects participated in structural magnetic resonance imaging (MRI) scans. The whole-brain images were segmented and normalized to a standard stereotactic space. Regional gray matter volumes were compared between the PWS group and the control group using voxel-based morphometry. The PWS subjects showed small gray-matter volume in several regions, including the OFC, caudate nucleus, inferior temporal gyrus, precentral gyrus, supplementary motor area, postcentral gyrus, and cerebellum. The small gray-matter volume in the OFC remained significant in a separate analysis that included total gray matter volume as a covariate. These preliminary findings suggest that the neurobehavioral symptoms in individuals with PWS are related to structural brain abnormalities in these areas. Copyright © 2010 Wiley-Liss, Inc.

The Neuroeconomics of Tobacco Demand: An Initial Investigation of the Neural Correlates of Cigarette Cost-Benefit Decision Making in Male Smokers

PubMed Central

Gray, Joshua C.; Amlung, Michael T.; Owens, Max; Acker, John; Brown, Courtney L.; Brody, Gene H.; Sweet, Lawrence H.; MacKillop, James

2017-01-01

How the brain processes cigarette cost-benefit decision making remains largely unknown. Using functional magnetic resonance imaging (fMRI), this study investigated the neural correlates of decisions for cigarettes (0–10 cigarettes) at varying levels of price during a Cigarette Purchase Task (CPT) in male regular smokers (N = 35). Differential neural activity was examined between choices classified as inelastic, elastic, and suppressed demand, operationalized as consumption unaffected by cost, partially suppressed by cost, and entirely suppressed by cost, respectively. Decisions reflecting elastic demand, putatively the most effortful decisions, elicited greater activation in regions associated with inhibition and planning (e.g., middle frontal gyrus and inferior frontal gyrus), craving and interoceptive processing (anterior insula), and conflict monitoring (e.g., anterior cingulate cortex). Exploratory examination in a harmonized dataset of both cigarette and alcohol demand (N = 59) suggested common neural activation patterns across commodities, particularly in the anterior insula, caudate, anterior cingulate, medial frontal gyrus, and dorsolateral prefrontal cortex. Collectively, these findings provide initial validation of a CPT fMRI paradigm; reveal the interplay of brain regions associated with executive functioning, incentive salience, and interoceptive processing in cigarette decision making; and add to the literature implicating the insula as a key brain region in addiction. PMID:28157228

The Neuroeconomics of Tobacco Demand: An Initial Investigation of the Neural Correlates of Cigarette Cost-Benefit Decision Making in Male Smokers.

PubMed

Gray, Joshua C; Amlung, Michael T; Owens, Max; Acker, John; Brown, Courtney L; Brody, Gene H; Sweet, Lawrence H; MacKillop, James

2017-02-03

How the brain processes cigarette cost-benefit decision making remains largely unknown. Using functional magnetic resonance imaging (fMRI), this study investigated the neural correlates of decisions for cigarettes (0-10 cigarettes) at varying levels of price during a Cigarette Purchase Task (CPT) in male regular smokers (N = 35). Differential neural activity was examined between choices classified as inelastic, elastic, and suppressed demand, operationalized as consumption unaffected by cost, partially suppressed by cost, and entirely suppressed by cost, respectively. Decisions reflecting elastic demand, putatively the most effortful decisions, elicited greater activation in regions associated with inhibition and planning (e.g., middle frontal gyrus and inferior frontal gyrus), craving and interoceptive processing (anterior insula), and conflict monitoring (e.g., anterior cingulate cortex). Exploratory examination in a harmonized dataset of both cigarette and alcohol demand (N = 59) suggested common neural activation patterns across commodities, particularly in the anterior insula, caudate, anterior cingulate, medial frontal gyrus, and dorsolateral prefrontal cortex. Collectively, these findings provide initial validation of a CPT fMRI paradigm; reveal the interplay of brain regions associated with executive functioning, incentive salience, and interoceptive processing in cigarette decision making; and add to the literature implicating the insula as a key brain region in addiction.

Accelerated aging-related transcriptome changes in the female prefrontal cortex

PubMed Central

Yuan, Yuan; Chen, Yi-Ping Phoebe; Boyd-Kirkup, Jerome; Khaitovich, Philipp; Somel, Mehmet

2012-01-01

Human female life expectancy is higher than that of males. Intriguingly, it has been reported that women display faster rates of age-related cognitive decline and a higher prevalence of Alzheimer’s disease (AD). To assess the molecular bases of these contradictory trends, we analyzed differences in expression changes with age between adult males and females, in four brain regions. In the superior frontal gyrus (SFG), a part of the prefrontal cortex, we observed manifest differences between the two sexes in the timing of age-related changes, that is, sexual heterochrony. Intriguingly, age-related expression changes predominantly occurred earlier, or at a faster pace, in females compared to men. These changes included decreased energy production and neural function and up-regulation of the immune response, all major features of brain aging. Furthermore, we found that accelerated expression changes in the female SFG correlated with expression changes observed in AD, as well as stress effects in the frontal cortex. Accelerated aging-related changes in the female SFG transcriptome may provide a link between a higher stress exposure or sensitivity in women and the higher prevalence of AD. PMID:22783978

Intrinsic resting-state activity predicts working memory brain activation and behavioral performance.

PubMed

Zou, Qihong; Ross, Thomas J; Gu, Hong; Geng, Xiujuan; Zuo, Xi-Nian; Hong, L Elliot; Gao, Jia-Hong; Stein, Elliot A; Zang, Yu-Feng; Yang, Yihong

2013-12-01

Although resting-state brain activity has been demonstrated to correspond with task-evoked brain activation, the relationship between intrinsic and evoked brain activity has not been fully characterized. For example, it is unclear whether intrinsic activity can also predict task-evoked deactivation and whether the rest-task relationship is dependent on task load. In this study, we addressed these issues on 40 healthy control subjects using resting-state and task-driven [N-back working memory (WM) task] functional magnetic resonance imaging data collected in the same session. Using amplitude of low-frequency fluctuation (ALFF) as an index of intrinsic resting-state activity, we found that ALFF in the middle frontal gyrus and inferior/superior parietal lobules was positively correlated with WM task-evoked activation, while ALFF in the medial prefrontal cortex, posterior cingulate cortex, superior frontal gyrus, superior temporal gyrus, and fusiform gyrus was negatively correlated with WM task-evoked deactivation. Further, the relationship between the intrinsic resting-state activity and task-evoked activation in lateral/superior frontal gyri, inferior/superior parietal lobules, superior temporal gyrus, and midline regions was stronger at higher WM task loads. In addition, both resting-state activity and the task-evoked activation in the superior parietal lobule/precuneus were significantly correlated with the WM task behavioral performance, explaining similar portions of intersubject performance variance. Together, these findings suggest that intrinsic resting-state activity facilitates or is permissive of specific brain circuit engagement to perform a cognitive task, and that resting activity can predict subsequent task-evoked brain responses and behavioral performance. Copyright © 2012 Wiley Periodicals, Inc.

Topographical distribution of decrements and recovery in muscarinic receptors from rat brains repeatedly exposed to sublethal doses of soman

DOE Office of Scientific and Technical Information (OSTI.GOV)

Churchill, L.; Pazdernik, T.L.; Jackson, J.L.

1984-08-01

(3H)Quinuclidinyl benzilate binding to rat brain muscarinic receptors decreased after repeated exposure to soman, a potent organophosphorus cholinesterase inhibitor. The topographical distribution of this decrement was analyzed by quantitative receptor autoradiography. After 4 weeks of soman, three times a week, quinuclidinyl benzilate binding decreased to 67 to 80% of control in frontal and parietal cortex, caudate-putamen, lateral septum, hippocampal body, dentate gyrus, superior colliculus, nucleus of the fifth nerve, and central grey. Minor or no decreases were observed in thalamic or hypothalamic nuclei, reticular formation, pontine nuclei, inferior colliculus, nucleus of the seventh nerve, and cerebellum. Scatchard analyses of saturationmore » curves using frontal cortex sections from soman-treated rats revealed a decrease in maximal quinuclidinyl benzilate binding from that in control rats and a return toward control levels by 24 days without any significant change in affinity. These brain areas showing significant decrements in muscarinic receptors recovered with a similar time course. An estimate of the time for 50% recovery for some of the brain areas was 14 days for superior colliculus, 16 days for cortex, and 19 days for hippocampal body. The application of quantitative receptor autoradiography to analyze receptor alterations has been valuable in localizing the telencephalon as a region more susceptible to change in receptor concentration.« less

Intracranial spectral amplitude dynamics of perceptual suppression in fronto-insular, occipito-temporal, and primary visual cortex

PubMed Central

Vidal, Juan R.; Perrone-Bertolotti, Marcela; Kahane, Philippe; Lachaux, Jean-Philippe

2015-01-01

If conscious perception requires global information integration across active distant brain networks, how does the loss of conscious perception affect neural processing in these distant networks? Pioneering studies on perceptual suppression (PS) described specific local neural network responses in primary visual cortex, thalamus and lateral prefrontal cortex of the macaque brain. Yet the neural effects of PS have rarely been studied with intracerebral recordings outside these cortices and simultaneously across distant brain areas. Here, we combined (1) a novel experimental paradigm in which we produced a similar perceptual disappearance and also re-appearance by using visual adaptation with transient contrast changes, with (2) electrophysiological observations from human intracranial electrodes sampling wide brain areas. We focused on broadband high-frequency (50–150 Hz, i.e., gamma) and low-frequency (8–24 Hz) neural activity amplitude modulations related to target visibility and invisibility. We report that low-frequency amplitude modulations reflected stimulus visibility in a larger ensemble of recording sites as compared to broadband gamma responses, across distinct brain regions including occipital, temporal and frontal cortices. Moreover, the dynamics of the broadband gamma response distinguished stimulus visibility from stimulus invisibility earlier in anterior insula and inferior frontal gyrus than in temporal regions, suggesting a possible role of fronto-insular cortices in top–down processing for conscious perception. Finally, we report that in primary visual cortex only low-frequency amplitude modulations correlated directly with perceptual status. Interestingly, in this sensory area broadband gamma was not modulated during PS but became positively modulated after 300 ms when stimuli were rendered visible again, suggesting that local networks could be ignited by top–down influences during conscious perception. PMID:25642199

Distinct frontal regions subserve evaluation of linguistic and emotional aspects of speech intonation.

PubMed

Wildgruber, D; Hertrich, I; Riecker, A; Erb, M; Anders, S; Grodd, W; Ackermann, H

2004-12-01

In addition to the propositional content of verbal utterances, significant linguistic and emotional information is conveyed by the tone of speech. To differentiate brain regions subserving processing of linguistic and affective aspects of intonation, discrimination of sentences differing in linguistic accentuation and emotional expressiveness was evaluated by functional magnetic resonance imaging. Both tasks yielded rightward lateralization of hemodynamic responses at the level of the dorsolateral frontal cortex as well as bilateral thalamic and temporal activation. Processing of linguistic and affective intonation, thus, seems to be supported by overlapping neural networks comprising partially right-sided brain regions. Comparison of hemodynamic activation during the two different tasks, however, revealed bilateral orbito-frontal responses restricted to the affective condition as opposed to activation of the left lateral inferior frontal gyrus confined to evaluation of linguistic intonation. These findings indicate that distinct frontal regions contribute to higher level processing of intonational information depending on its communicational function. In line with other components of language processing, discrimination of linguistic accentuation seems to be lateralized to the left inferior-lateral frontal region whereas bilateral orbito-frontal areas subserve evaluation of emotional expressiveness.

Midline frontal cortex low-frequency activity drives subthalamic nucleus oscillations during conflict.

PubMed

Zavala, Baltazar A; Tan, Huiling; Little, Simon; Ashkan, Keyoumars; Hariz, Marwan; Foltynie, Thomas; Zrinzo, Ludvic; Zaghloul, Kareem A; Brown, Peter

2014-05-21

Making the right decision from conflicting information takes time. Recent computational, electrophysiological, and clinical studies have implicated two brain areas as being crucial in assuring sufficient time is taken for decision-making under conditions of conflict: the medial prefrontal cortex and the subthalamic nucleus (STN). Both structures exhibit an elevation of activity at low frequencies (<10 Hz) during conflict that correlates with the amount of time taken to respond. This suggests that the two sites could become functionally coupled during conflict. To establish the nature of this interaction we recorded from deep-brain stimulation electrodes implanted bilaterally in the STN of 13 Parkinson's disease patients while they performed a sensory integration task involving randomly moving dots. By gradually increasing the number of dots moving coherently in one direction, we were able to determine changes in the STN associated with response execution. Furthermore, by occasionally having 10% of the dots move in the opposite direction as the majority, we were able to identify an independent increase in STN theta-delta activity triggered by conflict. Crucially, simultaneous midline frontal electroencephalographic recordings revealed an increase in the theta-delta band coherence between the two structures that was specific to high-conflict trials. Activity over the midline frontal cortex was Granger causal to that in STN. These results establish the cortico-subcortical circuit enabling successful choices to be made under conditions of conflict and provide support for the hypothesis that the brain uses frequency-specific channels of communication to convey behaviorally relevant information. Copyright © 2014 Zavala et al.

The "handwriting brain": a meta-analysis of neuroimaging studies of motor versus orthographic processes.

PubMed

Planton, Samuel; Jucla, Mélanie; Roux, Franck-Emmanuel; Démonet, Jean-François

2013-01-01

Handwriting is a modality of language production whose cerebral substrates remain poorly known although the existence of specific regions is postulated. The description of brain damaged patients with agraphia and, more recently, several neuroimaging studies suggest the involvement of different brain regions. However, results vary with the methodological choices made and may not always discriminate between "writing-specific" and motor or linguistic processes shared with other abilities. We used the "Activation Likelihood Estimate" (ALE) meta-analytical method to identify the cerebral network of areas commonly activated during handwriting in 18 neuroimaging studies published in the literature. Included contrasts were also classified according to the control tasks used, whether non-specific motor/output-control or linguistic/input-control. These data were included in two secondary meta-analyses in order to reveal the functional role of the different areas of this network. An extensive, mainly left-hemisphere network of 12 cortical and sub-cortical areas was obtained; three of which were considered as primarily writing-specific (left superior frontal sulcus/middle frontal gyrus area, left intraparietal sulcus/superior parietal area, right cerebellum) while others related rather to non-specific motor (primary motor and sensorimotor cortex, supplementary motor area, thalamus and putamen) or linguistic processes (ventral premotor cortex, posterior/inferior temporal cortex). This meta-analysis provides a description of the cerebral network of handwriting as revealed by various types of neuroimaging experiments and confirms the crucial involvement of the left frontal and superior parietal regions. These findings provide new insights into cognitive processes involved in handwriting and their cerebral substrates. Copyright © 2013 Elsevier Ltd. All rights reserved.

Expression of cellular prion protein in the frontal and occipital lobe in Alzheimer's disease, diffuse Lewy body disease, and in normal brain: an immunohistochemical study.

PubMed

Rezaie, Payam; Pontikis, Charlie C; Hudson, Lance; Cairns, Nigel J; Lantos, Peter L

2005-08-01

Cellular prion protein (PrP(c)) is a glycoprotein expressed at low to moderate levels within the nervous system. Recent studies suggest that PrP(c) may possess neuroprotective functions and that its expression is upregulated in certain neurodegenerative disorders. We investigated whether PrP(c) expression is altered in the frontal and occipital cortex in two well-characterized neurodegenerative disorders--Alzheimer's disease (AD) and diffuse Lewy body disease (DLBD)--compared with that in normal human brain using immunohistochemistry and computerized image analysis. The distribution of PrP(c) was further tested for correlation with glial reactivity. We found that PrP(c) was localized mainly in the gray matter (predominantly in neurons) and expressed at higher levels within the occipital cortex in the normal human brain. Image analysis revealed no significant variability in PrP(c) expression between DLBD and control cases. However, blood vessels within the white matter of DLBD cases showed immunoreactivity to PrP(c). By contrast, this protein was differentially expressed in the frontal and occipital cortex of AD cases; it was markedly overexpressed in the former and significantly reduced in the latter. Epitope specificity of antibodies appeared important when detecting PrP(c). The distribution of PrP(c) did not correlate with glial immunoreactivity. In conclusion, this study supports the proposal that regional changes in expression of PrP(c) may occur in certain neurodegenerative disorders such as AD, but not in other disorders such as DLBD.

Frontal lobe functioning during a simple response conflict task in first-episode psychosis and its relationship to treatment response.

PubMed

Shafritz, Keith M; Ikuta, Toshikazu; Greene, Allison; Robinson, Delbert G; Gallego, Juan; Lencz, Todd; DeRosse, Pamela; Kingsley, Peter B; Szeszko, Philip R

2018-05-09

Prior functional magnetic resonance imaging (fMRI) studies have investigated the neural mechanisms underlying cognitive control in patients with psychosis with findings of both hypo- and hyperfrontality. One factor that may contribute to inconsistent findings is the use of complex and polyfactorial tasks to investigate frontal lobe functioning. In the current study we employed a simple response conflict task during fMRI to examine differences in brain activation between patients experiencing their first-episode of psychosis (n = 33) and age- and sex-matched healthy volunteers (n = 33). We further investigated whether baseline brain activation among patients predicted changes in symptom severity and treatment response following 12 weeks of controlled antipsychotic treatment. During the task subjects were instructed to press a response button on the same side or opposite side of a circle that appeared on either side of a central fixation point. Imaging data revealed that for the contrast of opposite-side vs. same-side, patients showed significantly greater activation compared with healthy volunteers in the anterior cingulate cortex and intraparietal sulcus. Among patients, greater baseline anterior cingulate cortex, temporal-parietal junction, and superior temporal cortex activation predicted greater symptom reduction and therapeutic response following treatment. All findings remained significant after covarying for task performance. Intact performance on this relatively parsimonious task was associated with frontal hyperactivity suggesting the need for patients to utilize greater neural resources to achieve task performance comparable to healthy individuals. Moreover, frontal hyperactivity observed using a simple fMRI task may provide a biomarker for predicting treatment response in first-episode psychosis.

Pediatric respiratory and systemic effects of chronic air pollution exposure: nose, lung, heart, and brain pathology.

PubMed

Calderón-Garcidueñas, Lilian; Franco-Lira, Maricela; Torres-Jardón, Ricardo; Henriquez-Roldán, Carlos; Barragán-Mejía, Gerardo; Valencia-Salazar, Gildardo; González-Maciel, Angelica; Reynoso-Robles, Rafael; Villarreal-Calderón, Rafael; Reed, William

2007-01-01

Exposures to particulate matter and gaseous air pollutants have been associated with respiratory tract inflammation, disruption of the nasal respiratory and olfactory barriers, systemic inflammation, production of mediators of inflammation capable of reaching the brain and systemic circulation of particulate matter. Mexico City (MC) residents are exposed to significant amounts of ozone, particulate matter and associated lipopolysaccharides. MC dogs exhibit brain inflammation and an acceleration of Alzheimer's-like pathology, suggesting that the brain is adversely affected by air pollutants. MC children, adolescents and adults have a significant upregulation of cyclooxygenase-2 (COX2) and interleukin-1beta (IL-1beta) in olfactory bulb and frontal cortex, as well as neuronal and astrocytic accumulation of the 42 amino acid form of beta -amyloid peptide (Abeta 42), including diffuse amyloid plaques in frontal cortex. The pathogenesis of Alzheimer's disease (AD) is characterized by brain inflammation and the accumulation of Abeta 42, which precede the appearance of neuritic plaques and neurofibrillary tangles, the pathological hallmarks of AD. Our findings of nasal barrier disruption, systemic inflammation, and the upregulation of COX2 and IL-1beta expression and Abeta 42 accumulation in brain suggests that sustained exposures to significant concentrations of air pollutants such as particulate matter could be a risk factor for AD and other neurodegenerative diseases.

Brain connectivity and psychiatric comorbidity in adolescents with Internet gaming disorder.

PubMed

Han, Doug Hyun; Kim, Sun Mi; Bae, Sujin; Renshaw, Perry F; Anderson, Jeffrey S

2017-05-01

Prolonged Internet video game play may have multiple and complex effects on human cognition and brain development in both negative and positive ways. There is not currently a consensus on the principle effects of video game play neither on brain development nor on the relationship to psychiatric comorbidity. In this study, 78 adolescents with Internet gaming disorder (IGD) and 73 comparison subjects without IGD, including subgroups with no other psychiatric comorbid disease, with major depressive disorder and with attention deficit hyperactivity disorder (ADHD), were included in a 3 T resting state functional magnetic resonance imaging analysis. The severity of Internet gaming disorder, depression, anxiety and ADHD symptoms were assessed with the Young Internet Addiction Scale, the Beck Depression Inventory, the Beck Anxiety Inventory and the Korean ADHD rating scales, respectively. Patients with IGD showed an increased functional correlation between seven pairs of regions, all satisfying q < 0.05 False discovery rates in light of multiple statistical tests: left frontal eye field to dorsal anterior cingulate, left frontal eye field to right anterior insula, left dorsolateral prefrontal cortex (DLPFC) to left temporoparietal junction (TPJ), right DLPFC to right TPJ, right auditory cortex to right motor cortex, right auditory cortex to supplementary motor area and right auditory cortex to dorsal anterior cingulate. These findings may represent a training effect of extended game play and suggest a risk or predisposition in game players for over-connectivity of the default mode and executive control networks that may relate to psychiatric comorbidity. © 2015 Society for the Study of Addiction.

Adverse Effects of Cannabis on Adolescent Brain Development: A Longitudinal Study.

PubMed

Camchong, Jazmin; Lim, Kelvin O; Kumra, Sanjiv

2017-03-01

Cannabis is widely perceived as a safe recreational drug and its use is increasing in youth. It is important to understand the implications of cannabis use during childhood and adolescence on brain development. This is the first longitudinal study that compared resting functional connectivity of frontally mediated networks between 43 healthy controls (HCs; 20 females; age M = 16.5 ± 2.7) and 22 treatment-seeking adolescents with cannabis use disorder (CUD; 8 females; age M = 17.6 ± 2.4). Increases in resting functional connectivity between caudal anterior cingulate cortex (ACC) and superior frontal gyrus across time were found in HC, but not in CUD. CUD showed a decrease in functional connectivity between caudal ACC and dorsolateral and orbitofrontal cortices across time. Lower functional connectivity between caudal ACC cortex and orbitofrontal cortex at baseline predicted higher amounts of cannabis use during the following 18 months. Finally, high amounts of cannabis use during the 18-month interval predicted lower intelligence quotient and slower cognitive function measured at follow-up. These data provide compelling longitudinal evidence suggesting that repeated exposure to cannabis during adolescence may have detrimental effects on brain resting functional connectivity, intelligence, and cognitive function. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Common and Distinct Neural Mechanisms of Attentional Switching and Response Conflict

PubMed Central

Kim, Chobok; Johnson, Nathan F.; Gold, Brian T.

2012-01-01

The human capacities for overcoming prepotent actions and flexibly switching between tasks represent cornerstones of cognitive control. Functional neuroimaging has implicated a diverse set of brain regions contributing to each of these cognitive control processes. However, the extent to which attentional switching and response conflict draw on shared or distinct neural mechanisms remains unclear. The current study examined the neural correlates of response conflict and attentional switching using event-related functional magnetic resonance imaging (fMRI) and a fully randomized 2×2 design. We manipulated an arrow-word version of the Stroop task to measure conflict and switching in the context of a single task decision, in response to a common set of stimuli. Under these common conditions, both behavioral and imaging data showed significant main effects of conflict and switching but no interaction. However, conjunction analyses identified frontal regions involved in both switching and response conflict, including the dorsal anterior cingulate cortex (dACC) and left inferior frontal junction. In addition, connectivity analyses demonstrated task-dependent functional connectivity patterns between dACC and inferior temporal cortex for attentional switching and between dACC and posterior parietal cortex for response conflict. These results suggest that the brain makes use of shared frontal regions, but can dynamically modulate the connectivity patterns of some of those regions, to deal with attentional switching and response conflict. PMID:22750124

Common and distinct neural mechanisms of attentional switching and response conflict.

PubMed

Kim, Chobok; Johnson, Nathan F; Gold, Brian T

2012-08-21

The human capacities for overcoming prepotent actions and flexibly switching between tasks represent cornerstones of cognitive control. Functional neuroimaging has implicated a diverse set of brain regions contributing to each of these cognitive control processes. However, the extent to which attentional switching and response conflict draw on shared or distinct neural mechanisms remains unclear. The current study examined the neural correlates of response conflict and attentional switching using event-related functional magnetic resonance imaging (fMRI) and a fully randomized 2×2 design. We manipulated an arrow-word version of the Stroop task to measure conflict and switching in the context of a single task decision, in response to a common set of stimuli. Under these common conditions, both behavioral and imaging data showed significant main effects of conflict and switching but no interaction. However, conjunction analyses identified frontal regions involved in both switching and response conflict, including the dorsal anterior cingulate cortex (dACC) and left inferior frontal junction. In addition, connectivity analyses demonstrated task-dependent functional connectivity patterns between dACC and inferior temporal cortex for attentional switching and between dACC and posterior parietal cortex for response conflict. These results suggest that the brain makes use of shared frontal regions, but can dynamically modulate the connectivity patterns of some of those regions, to deal with attentional switching and response conflict. Copyright © 2012 Elsevier B.V. All rights reserved.

Antidepressant-like effect of oleanolic acid in mice exposed to the repeated forced swimming test.

PubMed

Yi, Li-Tao; Li, Jing; Liu, Qing; Geng, Di; Zhou, Ya-Fei; Ke, Xiao-Qing; Chen, Huan; Weng, Lian-Jin

2013-05-01

The study aimed to explore the antidepressant-like effect of oleanolic acid and its possible mechanism related to the monoaminergic system and neurotrophin in mice exposed to the repeated forced swimming test (FST). Both the duration and the latency of immobility affected by oleanolic acid (10, 20 and 40 mg/kg) were evaluated in the FST repeated at intervals on days 1, 7 and 14, followed by neurochemical and brain-derived neurotrophic factor (BDNF) analyses in the mouse brain regions of frontal cortex and whole hippocampus. A repeated analysis of variance (ANOVA) indicated that over retesting the immobility time increased, whereas latency to immobility tended to decrease. Minute-by-minute analysis showed that immobility time also increased during the 4-min course of the test. In addition, post-hoc Dunnett's test demonstrated that sub-chronic and chronic, but not acute, oleanolic acid treatment reduced the immobility time (sub-chronic: 20 mg/kg, 43.5%; chronic: 10 mg/kg, 19.3%; 20 mg/kg, 31.8%) and increased the latency to immobility (sub-chronic: 10 mg/kg, 60.6%; 20 mg/kg, 80.1%; chronic: 10 mg/kg, 121.8%; 20 mg/kg, 140.8%; 40 mg/kg, 80.0%). Furthermore, chronic administration of oleanolic acid significantly increased serotonin (5-HT) levels (frontal cortex: 44.5%, 41.9%, 27.5% for 10, 20, 40 mg/kg; hippocampus: 57.2%, 80.9% for 10, 20 mg/kg), decreased 5-hydroxyindoleacetic acid (5-HIAA)/5-HT ratio (frontal cortex: 31.6%, 30.1%, 23.5%; hippocampus: 40.6%, 47.7%, 29.2% for 10, 20, 40 mg/kg) and elevated norepinephrine (NE) levels (hippocampus: 20 mg/kg, 45.4%) but did not alter dopamine (DA) levels. Moreover, BDNF levels in the two brain regions were also elevated by chronic oleanolic acid treatment (frontal cortex: 20 mg/kg, 67.2%; hippocampus: 10 mg/kg, 36.4%; 20 mg/kg, 55.1%). Taken together, these findings imply that functions of 5-HT, NE and BDNF may be involved in the antidepressant-like effect of oleanolic acid.

Uncaria rhynchophylla upregulates the expression of MIF and cyclophilin A in kainic acid-induced epilepsy rats: A proteomic analysis.

PubMed

Lo, Wan-Yu; Tsai, Fuu-Jen; Liu, Chung-Hsiang; Tang, Nou-Ying; Su, Shan-Yu; Lin, Shinn-Zong; Chen, Chun-Chung; Shyu, Woei-Cherng; Hsieh, Ching-Liang

2010-01-01

Uncaria rhynchophylla (Miq) Jack (UR) is a traditional Chinese herb and is used for the treatment of convulsive disorders, including epilepsy. Our previous study has shown that UR, as well as its major component rhynchophylline (RH), has an anticonvulsive effect and this effect is closely related to its scavenging activities of oxygen free radicals. The purpose of the present study was to investigate the effect of (UR) on the expression of proteins using a proteomics analysis in Sprague-Dawley (SD) rats with kainic acid (KA)-induced epileptic seizures. We profiled the differentially expressed proteins on two-dimensional electrophoresis (2-DE) maps derived from the frontal cortex and hippocampus of rat brain tissue 24 hours after KA-induced epileptic seizures. The results indicated that macrophage migration inhibitory factor (MIF) and cyclophilin A were under expressed in frontal cortex by an average of 0.19- and 0.23-fold, respectively. In the frontal cortex, MIF and cyclophilin A were significantly decreased in the KA group and these decreases were confirmed by the Western blots. However, in the hippocampus, only cyclophilin A was significantly decreased in the KA group. In addition, in real-time quantitative PCR (Q-PCR), MIF and cyclophilin A gene expressions were also significantly under expressed in the frontal cortex, and only the cyclophilin A gene was also significantly under expressed in the hippocampus in the KA group. These under expressions of MIF and cyclophilin A could be overcome by the treatment of UR and RH. In conclusion, the under expressions of MIF and cyclophilin A in the frontal cortex and hippocampus in KA-treated rats, which were overcome by both UR and UH treatment, suggesting that both MIF and cyclophilin A at least partly participate in the anticonvulsive effect of UR.

Parallel pathways from whisker and visual sensory cortices to distinct frontal regions of mouse neocortex

PubMed Central

Sreenivasan, Varun; Kyriakatos, Alexandros; Mateo, Celine; Jaeger, Dieter; Petersen, Carl C.H.

2016-01-01

Abstract. The spatial organization of mouse frontal cortex is poorly understood. Here, we used voltage-sensitive dye to image electrical activity in the dorsal cortex of awake head-restrained mice. Whisker-deflection evoked the earliest sensory response in a localized region of primary somatosensory cortex and visual stimulation evoked the earliest responses in a localized region of primary visual cortex. Over the next milliseconds, the initial sensory response spread within the respective primary sensory cortex and into the surrounding higher order sensory cortices. In addition, secondary hotspots in the frontal cortex were evoked by whisker and visual stimulation, with the frontal hotspot for whisker deflection being more anterior and lateral compared to the frontal hotspot evoked by visual stimulation. Investigating axonal projections, we found that the somatosensory whisker cortex and the visual cortex directly innervated frontal cortex, with visual cortex axons innervating a region medial and posterior to the innervation from somatosensory cortex, consistent with the location of sensory responses in frontal cortex. In turn, the axonal outputs of these two frontal cortical areas innervate distinct regions of striatum, superior colliculus, and brainstem. Sensory input, therefore, appears to map onto modality-specific regions of frontal cortex, perhaps participating in distinct sensorimotor transformations, and directing distinct motor outputs. PMID:27921067

Changes in functional brain networks following sports-related concussion in adolescents.

PubMed

Virji-Babul, Naznin; Hilderman, Courtney G E; Makan, Nadia; Liu, Aiping; Smith-Forrester, Jenna; Franks, Chris; Wang, Z J

2014-12-01

Sports-related concussion is a major public health issue; however, little is known about the underlying changes in functional brain networks in adolescents following injury. Our aim was to use the tools from graph theory to evaluate the changes in brain network properties following concussion in adolescent athletes. We recorded resting state electroencephalography (EEG) in 33 healthy adolescent athletes and 9 adolescent athletes with a clinical diagnosis of subacute concussion. Graph theory analysis was applied to these data to evaluate changes in brain networks. Global and local metrics of the structural properties of the graph were calculated for each group and correlated with Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores. Brain networks of both groups showed small-world topology with no statistically significant differences in the global metrics; however, significant differences were found in the local metrics. Specifically, in the concussed group, we noted: 1) increased values of betweenness and degree in frontal electrode sites corresponding to the (R) dorsolateral prefrontal cortex and the (R) inferior frontal gyrus and 2) decreased values of degree in the region corresponding to the (R) frontopolar prefrontal cortex. In addition, there was significant negative correlation between degree and hub value, with total symptom score at the electrode site corresponding to the (R) prefrontal cortex. This preliminary report in adolescent athletes shows for the first time that resting-state EEG combined with graph theoretical analysis may provide an objective method of evaluating changes in brain networks following concussion. This approach may be useful in identifying individuals at risk for future injury.

The amusic brain: in tune, out of key, and unaware.

PubMed

Peretz, Isabelle; Brattico, Elvira; Järvenpää, Miika; Tervaniemi, Mari

2009-05-01

Like language, music engagement is universal, complex and present early in life. However, approximately 4% of the general population experiences a lifelong deficit in music perception that cannot be explained by hearing loss, brain damage, intellectual deficiencies or lack of exposure. This musical disorder, commonly known as tone-deafness and now termed congenital amusia, affects mostly the melodic pitch dimension. Congenital amusia is hereditary and is associated with abnormal grey and white matter in the auditory cortex and the inferior frontal cortex. In order to relate these anatomical anomalies to the behavioural expression of the disorder, we measured the electrical brain activity of amusic subjects and matched controls while they monitored melodies for the presence of pitch anomalies. Contrary to current reports, we show that the amusic brain can track quarter-tone pitch differences, exhibiting an early right-lateralized negative brain response. This suggests near-normal neural processing of musical pitch incongruities in congenital amusia. It is important because it reveals that the amusic brain is equipped with the essential neural circuitry to perceive fine-grained pitch differences. What distinguishes the amusic from the normal brain is the limited awareness of this ability and the lack of responsiveness to the semitone changes that violate musical keys. These findings suggest that, in the amusic brain, the neural pitch representation cannot make contact with musical pitch knowledge along the auditory-frontal neural pathway.

Abnormal Intrinsic Functional Hubs in Severe Male Obstructive Sleep Apnea: Evidence from a Voxel-Wise Degree Centrality Analysis.

PubMed

Li, Haijun; Li, Lan; Shao, Yi; Gong, Honghan; Zhang, Wei; Zeng, Xianjun; Ye, Chenglong; Nie, Si; Chen, Liting; Peng, Dechang

2016-01-01

Obstructive sleep apnea (OSA) has been associated with changes in brain structure and regional function in certain brain areas. However, the functional features of network organization in the whole brain remain largely uncertain. The purpose of this study was to identify the OSA-related spatial centrality distribution of the whole brain functional network and to investigate the potential altered intrinsic functional hubs. Forty male patients with newly confirmed severe OSA on polysomnography, and well-matched good sleepers, participated in this study. All participants underwent a resting-state functional MRI scan and clinical and cognitive evaluation. Voxel-wise degree centrality (DC) was measured across the whole brain, and group difference in DC was compared. The relationship between the abnormal DC value and clinical variables was assessed using a linear correlation analysis. Remarkably similar spatial distributions of the functional hubs (high DC) were found in both groups. However, OSA patients exhibited a pattern of significantly reduced regional DC in the left middle occipital gyrus, posterior cingulate cortex, left superior frontal gyrus, and bilateral inferior parietal lobule, and DC was increased in the right orbital frontal cortex, bilateral cerebellum posterior lobes, and bilateral lentiform nucleus, including the putamen, extending to the hippocampus, and the inferior temporal gyrus, which overlapped with the functional hubs. Furthermore, a linear correlation analysis revealed that the DC value in the posterior cingulate cortex and left superior frontal gyrus were positively correlated with Montreal cognitive assessment scores, The DC value in the left middle occipital gyrus and bilateral inferior parietal lobule were negatively correlated with apnea-hypopnea index and arousal index in OSA patients. Our findings suggest that OSA patients exhibited specific abnormal intrinsic functional hubs including relatively reduced and increased DC. This expands our understanding of the functional characteristics of OSA, which may provide new insights into understanding the dysfunction and pathophysiology of OSA patients.

Dissociating frontal regions that co-lateralize with different ventral occipitotemporal regions during word processing.

PubMed

Seghier, Mohamed L; Price, Cathy J

2013-08-01

The ventral occipitotemporal sulcus (vOT) sustains strong interactions with the inferior frontal cortex during word processing. Consequently, activation in both regions co-lateralize towards the same hemisphere in healthy subjects. Because the determinants of lateralisation differ across posterior, middle and anterior vOT subregions, we investigated whether lateralisation in different inferior frontal regions would co-vary with lateralisation in the three different vOT subregions. A whole brain analysis found that, during semantic decisions on written words, laterality covaried in (1) posterior vOT and the precentral gyrus; (2) middle vOT and the pars opercularis, pars triangularis, and supramarginal gyrus; and (3) anterior vOT and the pars orbitalis, middle frontal gyrus and thalamus. These findings increase the spatial resolution of our understanding of how vOT interacts with other brain areas during semantic categorisation on words. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Dissociating frontal regions that co-lateralize with different ventral occipitotemporal regions during word processing☆

PubMed Central

Seghier, Mohamed L.; Price, Cathy J.

2013-01-01

The ventral occipitotemporal sulcus (vOT) sustains strong interactions with the inferior frontal cortex during word processing. Consequently, activation in both regions co-lateralize towards the same hemisphere in healthy subjects. Because the determinants of lateralisation differ across posterior, middle and anterior vOT subregions, we investigated whether lateralisation in different inferior frontal regions would co-vary with lateralisation in the three different vOT subregions. A whole brain analysis found that, during semantic decisions on written words, laterality covaried in (1) posterior vOT and the precentral gyrus; (2) middle vOT and the pars opercularis, pars triangularis, and supramarginal gyrus; and (3) anterior vOT and the pars orbitalis, middle frontal gyrus and thalamus. These findings increase the spatial resolution of our understanding of how vOT interacts with other brain areas during semantic categorisation on words. PMID:23728081

5-HT2A Receptor Binding in the Frontal Cortex of Parkinson's Disease Patients and Alpha-Synuclein Overexpressing Mice: A Postmortem Study

PubMed Central

Rasmussen, Nadja Bredo; Olesen, Mikkel Vestergaard; Plenge, Per; Klein, Anders Bue; Westin, Jenny E.; Fog, Karina

2016-01-01

The 5-HT2A receptor is highly involved in aspects of cognition and executive function and seen to be affected in neurodegenerative diseases like Alzheimer's disease and related to the disease pathology. Even though Parkinson's disease (PD) is primarily a motor disorder, reports of impaired executive function are also steadily being associated with this disease. Not much is known about the pathophysiology behind this. The aim of this study was thereby twofold: (1) to investigate 5-HT2A receptor binding levels in Parkinson's brains and (2) to investigate whether PD associated pathology, alpha-synuclein (AS) overexpression, could be associated with 5-HT2A alterations. Binding density for the 5-HT2A-specific radioligand [3H]-MDL 100.907 was measured in membrane suspensions of frontal cortex tissue from PD patients. Protein levels of AS were further measured using western blotting. Results showed higher AS levels accompanied by increased 5-HT2A receptor binding in PD brains. In a separate study, we looked for changes in 5-HT2A receptors in the prefrontal cortex in 52-week-old transgenic mice overexpressing human AS. We performed region-specific 5-HT2A receptor binding measurements followed by gene expression analysis. The transgenic mice showed lower 5-HT2A binding in the frontal association cortex that was not accompanied by changes in gene expression levels. This study is one of the first to look at differences in serotonin receptor levels in PD and in relation to AS overexpression. PMID:27579212

The neural bases of cognitive conflict and control in moral judgment.

PubMed

Greene, Joshua D; Nystrom, Leigh E; Engell, Andrew D; Darley, John M; Cohen, Jonathan D

2004-10-14

Traditional theories of moral psychology emphasize reasoning and "higher cognition," while more recent work emphasizes the role of emotion. The present fMRI data support a theory of moral judgment according to which both "cognitive" and emotional processes play crucial and sometimes mutually competitive roles. The present results indicate that brain regions associated with abstract reasoning and cognitive control (including dorsolateral prefrontal cortex and anterior cingulate cortex) are recruited to resolve difficult personal moral dilemmas in which utilitarian values require "personal" moral violations, violations that have previously been associated with increased activity in emotion-related brain regions. Several regions of frontal and parietal cortex predict intertrial differences in moral judgment behavior, exhibiting greater activity for utilitarian judgments. We speculate that the controversy surrounding utilitarian moral philosophy reflects an underlying tension between competing subsystems in the brain.

Abnormalities of Intrinsic Functional Connectivity in Autism Spectrum Disorders

PubMed Central

Monk, Christopher S.; Peltier, Scott J.; Wiggins, Jillian Lee; Weng, Shih-Jen; Carrasco, Melisa; Risi, Susan; Lord, Catherine

2009-01-01

Autism spectrum disorders (ASD) impact social functioning and communication, and individuals with these disorders often have restrictive and repetitive behaviors. Accumulating data indicate that ASD is associated with alterations of neural circuitry. Functional MRI (FMRI) studies have focused on connectivity in the context of psychological tasks. However, even in the absence of a task, the brain exhibits a high degree of functional connectivity, known as intrinsic or resting connectivity. Notably, the default network, which includes the posterior cingulate cortex, retro-splenial, lateral parietal cortex/angular gyrus, medial prefrontal cortex, superior frontal gyrus, temporal lobe, and parahippocampal gyrus, is strongly active when there is no task. Altered intrinsic connectivity within the default network may underlie offline processing that may actuate ASD impairments. Using FMRI, we sought to evaluate intrinsic connectivity within the default network in ASD. Relative to controls, the ASD group showed weaker connectivity between the posterior cingulate cortex and superior frontal gyrus and stronger connectivity between the posterior cingulate cortex and both the right temporal lobe and right parahippocampal gyrus. Moreover, poorer social functioning in the ASD group was correlated with weaker connectivity between the posterior cingulate cortex and the superior frontal gyrus. In addition, more severe restricted and repetitive behaviors in ASD were correlated with stronger connectivity between the posterior cingulate cortex and right parahippocampal gyrus. These findings indicate that ASD subjects show altered intrinsic connectivity within the default network, and connectivity between these structures is associated with specific ASD symptoms. PMID:19409498

Intentionality and "free-will" from a neurodevelopmental perspective.

PubMed

Leisman, Gerry; Machado, Calixto; Melillo, Robert; Mualem, Raed

2012-01-01

The nature of free-will as a subset of intentionality and probabilistic and deterministic function is explored with the indications being that human behavior is highly predictable which in turn, should compromise the notion of free-will. Data supports the notion that age relates to the ability to progressively effectively establish goals performed by fixed action patterns and that these FAPs produce outcomes that in turn modify choices (free-will) for which FAPs need to be employed. Early goals require behaviors that require greater automation in terms of FAPs that lead to goals being achieved or not; if not, then one can change behavior and that in turn is free-will. Goals change with age based on experience which is similar to the way in which movement functions. We hypothesize that human prefrontal cortex development was a natural expansion of the evolutionarily earlier developed areas of the frontal lobe and that goal-directed movements and behavior, including choice and free-will, provided for an expansion of those areas. The same regions of the human central nervous system that were already employed for better control, coordination, and timing of movements, expanded in parallel with the frontal cortex. The initial focus of the frontal lobes was the control of motor activity, but as the movements became more goal-directed, greater cognitive control over movement was necessitated leading to voluntary control of FAPs or free-will. The paper reviews the neurobiology, neurohistology, and electrophysiology of brain connectivities developmentally, along with the development of those brain functions linked to decision-making from a developmental viewpoint. The paper reviews the neurological development of the frontal lobes and inter-regional brain connectivities in the context of optimization of communication systems within the brain and nervous system and its relation to free-will.

Increased Neuronal DNA/RNA Oxidation in the Frontal Cortex of Mice Subjected to Unpredictable Chronic Mild Stress.

PubMed

Maluach, Alfred M; Misquitta, Keith A; Prevot, Thomas D; Fee, Corey; Sibille, Etienne; Banasr, Mounira; Andreazza, Ana C

2017-01-01

Chronic stress is implicated in the development of various psychiatric illnesses including major depressive disorder. Previous reports suggest that patients with major depressive disorder have increased levels of oxidative stress, including higher levels of DNA/RNA oxidation found in postmortem studies, especially within brain regions responsible for the cognitive and emotional processes disrupted in the disorder. Here, we aimed to investigate whether unpredictable chronic mild stress in mice induces neuronal DNA/RNA oxidation in the prelimbic, infralimbic, and cingulate cortices of the frontal cortex and the basolateral amygdala and to explore potential associations with depressive-like behaviors. We expected that animals subjected to unpredictable chronic mild stress will present higher levels of DNA/RNA oxidation, which will be associated with anxiety-/depressive-like behaviors. C57BL/6J mice were assigned to unpredictable chronic mild stress or nonstress conditions (n = 10/group, 50% females). Following five weeks of unpredictable chronic mild stress exposure, mice were tested in a series of behavioral tests measuring anxiety- and depressive-like behaviors. Frontal cortex and amygdala sections were then immunolabeled for neuronal nuclei, a marker of post-mitotic neurons and anti-8-hydroxy-2-deoxyguanosine/8-oxo-7,8-dihydroguanosine, which reflects both DNA and RNA oxidation. Levels of neuronal DNA/RNA oxidation were increased in the frontal cortex of mice subjected to unpredictable chronic mild stress ( p = 0.0207). Levels of neuronal DNA/RNA oxidation in the frontal cortex were positively correlated with z-emotionality scores for latency to feed in the novelty-suppressed feeding test ( p = 0.0031). Statistically significant differences were not detected in basolateral amygdala levels of neuronal DNA/RNA oxidation between nonstress- and unpredictable chronic mild stress-exposed mice, nor were correlations found with behavioral performances for this region. Our results demonstrate that unpredictable chronic mild stress induces a significant increase in neuronal DNA/RNA oxidation in the frontal cortex that correlate with behavioral readouts of the stress response. A lack of DNA/RNA oxidation alterations in the basolateral amygdala suggests greater vulnerability of frontal cortex neurons to DNA/RNA oxidation in response to unpredictable chronic mild stress. These findings add support to the hypothesis that chronic stress-induced damage to DNA/RNA may be an additional molecular mechanism underlying cellular dysfunctions associated with chronic stress and present in stress-related disorders.

Brain systems underlying encounter expectancy bias in spider phobia.

PubMed

Aue, Tatjana; Hoeppli, Marie-Eve; Piguet, Camille; Hofstetter, Christoph; Rieger, Sebastian W; Vuilleumier, Patrik

2015-06-01

Spider-phobic individuals are characterized by exaggerated expectancies to be faced with spiders (so-called encounter expectancy bias). Whereas phobic responses have been linked to brain systems mediating fear, little is known about how the recruitment of these systems relates to exaggerated expectancies of threat. We used fMRI to examine spider-phobic and control participants while they imagined visiting different locations in a forest after having received background information about the likelihood of encountering different animals (spiders, snakes, and birds) at these locations. Critically, imagined encounter expectancies modulated brain responses differently in phobics as compared with controls. Phobics displayed stronger negative modulation of activity in the lateral prefrontal cortex, precuneus, and visual cortex by encounter expectancies for spiders, relative to snakes or birds (within-participants analysis); these effects were not seen in controls. Between-participants correlation analyses within the phobic group further corroborated the hypothesis that these phobia-specific modulations may underlie irrationality in encounter expectancies (deviations of encounter expectancies from objective background information) in spider phobia; the greater the negative modulation a phobic participant displayed in the lateral prefrontal cortex, precuneus, and visual cortex, the stronger was her bias in encounter expectancies for spiders. Interestingly, irrationality in expectancies reflected in frontal areas relied on right rather than left hemispheric deactivations. Our data accord with the idea that expectancy biases in spider phobia may reflect deficiencies in cognitive control and contextual integration that are mediated by right frontal and parietal areas.

Cascade of neural processing orchestrates cognitive control in human frontal cortex

PubMed Central

Tang, Hanlin; Yu, Hsiang-Yu; Chou, Chien-Chen; Crone, Nathan E; Madsen, Joseph R; Anderson, William S; Kreiman, Gabriel

2016-01-01

Rapid and flexible interpretation of conflicting sensory inputs in the context of current goals is a critical component of cognitive control that is orchestrated by frontal cortex. The relative roles of distinct subregions within frontal cortex are poorly understood. To examine the dynamics underlying cognitive control across frontal regions, we took advantage of the spatiotemporal resolution of intracranial recordings in epilepsy patients while subjects resolved color-word conflict. We observed differential activity preceding the behavioral responses to conflict trials throughout frontal cortex; this activity was correlated with behavioral reaction times. These signals emerged first in anterior cingulate cortex (ACC) before dorsolateral prefrontal cortex (dlPFC), followed by medial frontal cortex (mFC) and then by orbitofrontal cortex (OFC). These results disassociate the frontal subregions based on their dynamics, and suggest a temporal hierarchy for cognitive control in human cortex. DOI: http://dx.doi.org/10.7554/eLife.12352.001 PMID:26888070

The hemodynamic changes in the human prefrontal cortex during the Flanker and Simon tasks: a fNIRS study

NASA Astrophysics Data System (ADS)

Yuan, Zhen; Lin, Xiaohong

2016-03-01

Functional near-infrared spectroscopy (fNIRS) is a low-cost, portable and noninvasive functional neuroimaging technique by measuring the change in the concentrations of oxyhemoglobin (HbO) and deoxyhemoglobin (HbR). The aim of present study is to reveal the different brain activity pattern of adult subjects during the completion of flanker and Simon tasks underlying the congruent and incongruent test conditions so as to identify the basic neural mechanism of inhibitory control in executive function. In the study, we utilized fNIRS to explore the hemodynamic changes in the prefrontal cortex and our imaging results suggested that there were notable differences for the hemodynamic responses between the flank and Simon task. A striking difference is that for the flank task, the increase in the HbO concentration during incongruent trials was larger than that during congruent trials for the channels across middle frontal cortex while for the Simon task, the hemodynamic response was stronger for the congruent condition compared to that from the incongruent one. Interestingly, the hemodynamic response exhibited similar task-related activation in the superior frontal cortex for both the congruent and incongruent conditions. Further, independent component analysis showed that different brain activation patterns were identified to accomplish different inhibitory control tasks underlying the congruent and incongruent conditions.

Self-identification and empathy modulate error-related brain activity during the observation of penalty shots between friend and foe

PubMed Central

Ganesh, Shanti; van Schie, Hein T.; De Bruijn, Ellen R. A.; Bekkering, Harold

2009-01-01

The ability to detect and process errors made by others plays an important role is many social contexts. The capacity to process errors is typically found to rely on sites in the medial frontal cortex. However, it remains to be determined whether responses at these sites are driven primarily by action errors themselves or by the affective consequences normally associated with their commission. Using an experimental paradigm that disentangles action errors and the valence of their affective consequences, we demonstrate that sites in the medial frontal cortex (MFC), including the ventral anterior cingulate cortex (vACC) and pre-supplementary motor area (pre-SMA), respond to action errors independent of the valence of their consequences. The strength of this response was negatively correlated with the empathic concern subscale of the Interpersonal Reactivity Index. We also demonstrate a main effect of self-identification by showing that errors committed by friends and foes elicited significantly different BOLD responses in a separate region of the middle anterior cingulate cortex (mACC). These results suggest that the way we look at others plays a critical role in determining patterns of brain activation during error observation. These findings may have important implications for general theories of error processing. PMID:19015079

Unmasking Language Lateralization in Human Brain Intrinsic Activity

PubMed Central

McAvoy, Mark; Mitra, Anish; Coalson, Rebecca S.; d'Avossa, Giovanni; Keidel, James L.; Petersen, Steven E.; Raichle, Marcus E.

2016-01-01

Lateralization of function is a fundamental feature of the human brain as exemplified by the left hemisphere dominance of language. Despite the prominence of lateralization in the lesion, split-brain and task-based fMRI literature, surprisingly little asymmetry has been revealed in the increasingly popular functional imaging studies of spontaneous fluctuations in the fMRI BOLD signal (so-called resting-state fMRI). Here, we show the global signal, an often discarded component of the BOLD signal in resting-state studies, reveals a leftward asymmetry that maps onto regions preferential for semantic processing in left frontal and temporal cortex and the right cerebellum and a rightward asymmetry that maps onto putative attention-related regions in right frontal, temporoparietal, and parietal cortex. Hemispheric asymmetries in the global signal resulted from amplitude modulation of the spontaneous fluctuations. To confirm these findings obtained from normal, healthy, right-handed subjects in the resting-state, we had them perform 2 semantic processing tasks: synonym and numerical magnitude judgment and sentence comprehension. In addition to establishing a new technique for studying lateralization through functional imaging of the resting-state, our findings shed new light on the physiology of the global brain signal. PMID:25636911

Anti-correlated cortical networks of intrinsic connectivity in the rat brain.

PubMed

Schwarz, Adam J; Gass, Natalia; Sartorius, Alexander; Risterucci, Celine; Spedding, Michael; Schenker, Esther; Meyer-Lindenberg, Andreas; Weber-Fahr, Wolfgang

2013-01-01

In humans, resting-state blood oxygen level-dependent (BOLD) signals in the default mode network (DMN) are temporally anti-correlated with those from a lateral cortical network involving the frontal eye fields, secondary somatosensory and posterior insular cortices. Here, we demonstrate the existence of an analogous lateral cortical network in the rat brain, extending laterally from anterior secondary sensorimotor regions to the insular cortex and exhibiting low-frequency BOLD fluctuations that are temporally anti-correlated with a midline "DMN-like" network comprising posterior/anterior cingulate and prefrontal cortices. The primary nexus for this anti-correlation relationship was the anterior secondary motor cortex, close to regions that have been identified with frontal eye fields in the rat brain. The anti-correlation relationship was corroborated after global signal removal, underscoring this finding as a robust property of the functional connectivity signature in the rat brain. These anti-correlated networks demonstrate strong anatomical homology to networks identified in human and monkey connectivity studies, extend the known preserved functional connectivity relationships between rodent and primates, and support the use of resting-state functional magnetic resonance imaging as a translational imaging method between rat models and humans.

Anti-Correlated Cortical Networks of Intrinsic Connectivity in the Rat Brain

PubMed Central

Gass, Natalia; Sartorius, Alexander; Risterucci, Celine; Spedding, Michael; Schenker, Esther; Meyer-Lindenberg, Andreas; Weber-Fahr, Wolfgang

2013-01-01

Abstract In humans, resting-state blood oxygen level-dependent (BOLD) signals in the default mode network (DMN) are temporally anti-correlated with those from a lateral cortical network involving the frontal eye fields, secondary somatosensory and posterior insular cortices. Here, we demonstrate the existence of an analogous lateral cortical network in the rat brain, extending laterally from anterior secondary sensorimotor regions to the insular cortex and exhibiting low-frequency BOLD fluctuations that are temporally anti-correlated with a midline “DMN-like” network comprising posterior/anterior cingulate and prefrontal cortices. The primary nexus for this anti-correlation relationship was the anterior secondary motor cortex, close to regions that have been identified with frontal eye fields in the rat brain. The anti-correlation relationship was corroborated after global signal removal, underscoring this finding as a robust property of the functional connectivity signature in the rat brain. These anti-correlated networks demonstrate strong anatomical homology to networks identified in human and monkey connectivity studies, extend the known preserved functional connectivity relationships between rodent and primates, and support the use of resting-state functional magnetic resonance imaging as a translational imaging method between rat models and humans. PMID:23919836

Brain-derived neurotrophic factor (BDNF) and its precursor (proBDNF) in genetically defined fear-induced aggression.

PubMed

Ilchibaeva, Tatiana V; Kondaurova, Elena M; Tsybko, Anton S; Kozhemyakina, Rimma V; Popova, Nina K; Naumenko, Vladimir S

2015-09-01

The brain-derived neurotrophic factor (BDNF), its precursor (proBDNF) and BDNF mRNA levels were studied in the brain of wild rats selectively bred for more than 70 generations for either high level or for the lack of affective aggressiveness towards man. Significant increase of BDNF mRNA level in the frontal cortex and increase of BDNF level in the hippocampus of aggressive rats was revealed. In the midbrain and hippocampus of aggressive rats proBDNF level was increased, whereas BDNF/proBDNF ratio was reduced suggesting the prevalence and increased influence of proBDNF in highly aggressive rats. In the frontal cortex, proBDNF level in aggressive rats was decreased. Thus, considerable structure-specific differences in BDNF and proBDNF levels as well as in BDNF gene expression between highly aggressive and nonaggressive rats were shown. The data suggested the implication of BDNF and its precursor proBDNF in the mechanism of aggressiveness and in the creation of either aggressive or nonaggressive phenotype. Copyright © 2015 Elsevier B.V. All rights reserved.

Regional Brain Activity in Abstinent Methamphetamine Dependent Males Following Cue Exposure.

PubMed

Malcolm, Robert; Myrick, Hugh; Li, Xingbao; Henderson, Scott; Brady, Kathleen T; George, Mark S; See, Ronald E

Neuroimaging of drug-associated cue presentations has aided in understanding the neurobiological substrates of craving and relapse for cocaine, alcohol, and nicotine. However, imaging of cue-reactivity in methamphetamine addiction has been much less studied. Nine caucasian male methamphetamine-dependent subjects and nine healthy controls were scanned in a Phillips 3.0T MRI scan when they viewed a randomized presentation of visual cues of methamphetamine, neutral objects, and rest conditions. Functional Imaging data were analyzed with Statistical Parametric Mapping software 5 (SPM 5). Methamphetamine subjects had significant brain activation in the ventral striatum and medial frontal cortex in comparison to meth pictures and neutral pictures in healthy controls (p<0.005, threshold 15 voxels). Interestingly the ventral striatum activation significantly correlated with the days since the last use of meth (r=-0.76, p=0.017). No significant activity was found in healthy control group. The preliminary data suggest that methamphetamine dependent subjects, when exposed to methamphetamine-associated visual cues, have increased brain activity in ventral striatum, caudate nucleus and medial frontal cortex which subserve craving, drug-seeking, and drug use.

Peony glycosides reverse the effects of corticosterone on behavior and brain BDNF expression in rats.

PubMed

Mao, Qing-Qiu; Huang, Zhen; Ip, Siu-Po; Xian, Yan-Fang; Che, Chun-Tao

2012-02-01

Repeated injections of corticosterone (CORT) induce the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, resulting in depressive-like behavior. This study aimed to examine the antidepressant-like effect and the possible mechanisms of total glycosides of peony (TGP) in the CORT-induced depression model in rats. The results showed that the 3-week CORT injections induced the significant increase in serum CORT levels in rats. Repeated CORT injections also caused depression-like behavior in rats, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test. Moreover, it was found that brain-derived neurotrophic factor (BDNF) protein levels in the hippocampus and frontal cortex were significantly decreased in CORT-treated rats. Treatment of the rats with TGP significantly suppressed the depression-like behavior and increased brain BDNF levels in CORT-treated rats. The results suggest that TGP produces an antidepressant-like effect in CORT-treated rats, which is possibly mediated by increasing BDNF expression in the hippocampus and frontal cortex. Copyright © 2011 Elsevier B.V. All rights reserved.

Double Dissociation in the Anatomy of Socioemotional Disinhibition and Executive Functioning in Dementia

PubMed Central

Krueger, Casey E.; Laluz, Victor; Rosen, Howard J.; Neuhaus, John M.; Miller, Bruce L.; Kramer, Joel H.

2010-01-01

Objective To determine if socioemotional disinhibition and executive dysfunction are related to dissociable patterns of brain atrophy in neurodegenerative disease. Previous studies have indicated that behavioral and cognitive dysfunction in neurodegenerative disease are linked to atrophy in different parts of the frontal lobe, but these prior studies did not establish that these relationships were specific, which would best be demonstrated by a double dissociation. Method Subjects included 157 patients with neurodegenerative disease. A semi-automated parcellation program (Freesurfer) was used to generate regional cortical volumes from structural MRI scans. Regions of interest (ROIs) included anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), middle frontal gyrus (MFG) and inferior frontal gyrus (IFG). Socioemotional disinhibition was measured using the Neuropsychiatric Inventory. Principal component analysis including three tasks of executive function (EF; verbal fluency, Stroop Interference, modified Trails) was used to generate a single factor score to represent EF. Results Partial correlations between ROIs, disinhibition, and EF were computed after controlling for total intracranial volume, MMSE, diagnosis, age, and education. Brain regions significantly correlated with disinhibition (ACC, OFC, IFG, and temporal lobes) and EF (MFG) were entered into separate hierarchical regressions to determine which brain regions predicted disinhibition and EF. OFC was the only brain region to significantly predict disinhibition and MFG significantly predicted executive functioning performance. A multivariate general linear model demonstrated a significant interaction between ROIs and cognitive-behavioral functions. Conclusions These results support a specific association between orbitofrontal areas and behavioral management as compared to dorsolateral areas and EF. PMID:21381829

Balance Deficit and Brain Connectivity in Children with Attention-Deficit/Hyperactivity Disorder.

PubMed

Kim, Sun Mi; Hyun, Gi Jung; Jung, Tae-Woon; Son, Young Don; Cho, In-Hee; Kee, Baik Seok; Han, Doug Hyun

2017-07-01

We aimed to assess disturbances in postural and gait balance and functional connectivity within the brain regions controlling balance in children with attention-deficit/hyperactivity disorder (ADHD). Thirteen children with ADHD and 13 age- and sex-matched controls were recruited. Gait balance was assessed by the difference in the center of pressure (COP) between the left and right foot, as well as the difference in plantar pressure between the left and right foot during gait. Neuroimaging data were acquired using a 3.0 Tesla MRI scanner. Functional connectivity between the vermis of the cerebellum and all other brain regionswas assessed. The difference in plantar pressure between the left foot and right foot in the ADHD group was greater than that observed in the control group. The average COP jerk score of the right foot in the ADHD group was higher than that observed in the control group. A higher functional connectivity between the cerebellum and the right middle frontal gyrus (premotor cortex) and medial frontal gyrus (cingulate gyrus) was observed in the control group relative to the ADHD group. In the ADHD group, the difference in plantar pressure between the left and right foot was also negatively correlated with the beta-value within the middle frontal gyrus. Children with ADHD had disturbance of balance as assessed by plantar pressure. Decreased brain connectivity from the cerebellum to the premotor cortex and anterior cingulate was associated with disturbances of posture and balance in children with ADHD.

Action video gaming and the brain: fMRI effects without behavioral effects in visual and verbal cognitive tasks.

PubMed

Richlan, Fabio; Schubert, Juliane; Mayer, Rebecca; Hutzler, Florian; Kronbichler, Martin

2018-01-01

In this functional magnetic resonance imaging (fMRI) study, we compared task performance together with brain activation in a visuospatial task (VST) and a letter detection task (LDT) between longtime action video gamers ( N  =   14) and nongamers ( N  =   14) in order to investigate possible effects of gaming on cognitive and brain abilities. Based on previous research, we expected advantages in performance for experienced action video gamers accompanied by less activation (due to higher efficiency) as measured by fMRI in the frontoparietal attention network. Contrary to these expectations, we did not find differences in overall task performance, nor in brain activation during the VST. We identified, however, a significantly different increase in the BOLD signal from a baseline task to the LDT in action video gamers compared with nongamers. This increased activation was evident in a number of frontoparietal regions including the left middle paracingulate cortex, the left superior frontal sulcus, the opercular part of the left inferior frontal gyrus, and the left and right posterior parietal cortex. Furthermore, we found increased activation in the triangular part of the left inferior frontal gyrus in gamers relative to nongamers when activation during the LDT was compared with activation during the VST. In sum, the expected positive relation between action video game experience and cognitive performance could not be confirmed. Despite their comparable task performance, however, gamers and nongamers exhibited clear-cut differences in brain activation patterns presumably reflecting differences in neural engagement, especially during verbal cognitive tasks.

Neuroanatomical substrates of action perception and understanding: an anatomic likelihood estimation meta-analysis of lesion-symptom mapping studies in brain injured patients

PubMed Central

Urgesi, Cosimo; Candidi, Matteo; Avenanti, Alessio

2014-01-01

Several neurophysiologic and neuroimaging studies suggested that motor and perceptual systems are tightly linked along a continuum rather than providing segregated mechanisms supporting different functions. Using correlational approaches, these studies demonstrated that action observation activates not only visual but also motor brain regions. On the other hand, brain stimulation and brain lesion evidence allows tackling the critical question of whether our action representations are necessary to perceive and understand others’ actions. In particular, recent neuropsychological studies have shown that patients with temporal, parietal, and frontal lesions exhibit a number of possible deficits in the visual perception and the understanding of others’ actions. The specific anatomical substrates of such neuropsychological deficits however, are still a matter of debate. Here we review the existing literature on this issue and perform an anatomic likelihood estimation meta-analysis of studies using lesion-symptom mapping methods on the causal relation between brain lesions and non-linguistic action perception and understanding deficits. The meta-analysis encompassed data from 361 patients tested in 11 studies and identified regions in the inferior frontal cortex, the inferior parietal cortex and the middle/superior temporal cortex, whose damage is consistently associated with poor performance in action perception and understanding tasks across studies. Interestingly, these areas correspond to the three nodes of the action observation network that are strongly activated in response to visual action perception in neuroimaging research and that have been targeted in previous brain stimulation studies. Thus, brain lesion mapping research provides converging causal evidence that premotor, parietal and temporal regions play a crucial role in action recognition and understanding. PMID:24910603

Cerebral Apolipoprotein-D Is Hypoglycosylated Compared to Peripheral Tissues and Is Variably Expressed in Mouse and Human Brain Regions.

PubMed

Li, Hongyun; Ruberu, Kalani; Karl, Tim; Garner, Brett

2016-01-01

Recent studies have shown that cerebral apoD levels increase with age and in Alzheimer's disease (AD). In addition, loss of cerebral apoD in the mouse increases sensitivity to lipid peroxidation and accelerates AD pathology. Very little data are available, however, regarding the expression of apoD protein levels in different brain regions. This is important as both brain lipid peroxidation and neurodegeneration occur in a region-specific manner. Here we addressed this using western blotting of seven different regions (olfactory bulb, hippocampus, frontal cortex, striatum, cerebellum, thalamus and brain stem) of the mouse brain. Our data indicate that compared to most brain regions, the hippocampus is deficient in apoD. In comparison to other major organs and tissues (liver, spleen, kidney, adrenal gland, heart and skeletal muscle), brain apoD was approximately 10-fold higher (corrected for total protein levels). Our analysis also revealed that brain apoD was present at a lower apparent molecular weight than tissue and plasma apoD. Utilising peptide N-glycosidase-F and neuraminidase to remove N-glycans and sialic acids, respectively, we found that N-glycan composition (but not sialylation alone) were responsible for this reduction in molecular weight. We extended the studies to an analysis of human brain regions (hippocampus, frontal cortex, temporal cortex and cerebellum) where we found that the hippocampus had the lowest levels of apoD. We also confirmed that human brain apoD was present at a lower molecular weight than in plasma. In conclusion, we demonstrate apoD protein levels are variable across different brain regions, that apoD levels are much higher in the brain compared to other tissues and organs, and that cerebral apoD has a lower molecular weight than peripheral apoD; a phenomenon that is due to the N-glycan content of the protein.

Proton magnetic resonance spectroscopy (MRS) in on-line game addiction.

PubMed

Han, Doug Hyun; Lee, Young Sik; Shi, Xianfeng; Renshaw, Perry F

2014-11-01

Recent brain imaging studies suggested that both the frontal and temporal cortices are important candidate areas for mediating the symptoms of internet addiction. We hypothesized that deficits of prefrontal and temporal cortical function in patients with on-line game addiction (PGA) would be reflected in decreased levels of N-acetyl aspartate (NAA) and cytosolic, choline containing compound (Cho). Seventy three young PGA and 38 age and sex matched healthy control subjects were recruited in the study. Structural MR and (1)H MRS data were acquired using a 3.0 T MRI scanner. Voxels were sequentially placed in right frontal cortex and right medial temporal cortices. In the right frontal cortex, the levels of NAA in PGA were lower than those in healthy controls. In the medial temporal cortex, the levels of Cho in PGA participants were lower than those observed in healthy controls. The Young Internet Addiction Scale (YIAS) scores and perseverative responses in PGA were negatively correlated with the level of NAA in right frontal cortex. The Beck Depressive Inventory (BDI) scores in the PGA cohort were negatively correlated with Cho levels in the right temporal lobe. To the best of our knowledge, this is the first MRS study of individuals with on-line game addiction. Although, the subjects with on-line game addiction in the current study were free from psychiatric co-morbidity, patients with on-line game addiction appear to share characteristics with ADHD and MDD in terms of neurochemical changes in frontal and temporal cortices. Copyright © 2014 Elsevier Ltd. All rights reserved.

fMRI evidence for strategic decision-making during resolution of pronoun reference

PubMed Central

McMillan, Corey T.; Clark, Robin; Gunawardena, Delani; Ryant, Neville; Grossman, Murray

2012-01-01

Pronouns are extraordinarily common in daily language yet little is known about the neural mechanisms that support decisions about pronoun reference. We propose a large-scale neural network for resolving pronoun reference that consists of two components. First, a core language network in peri-Sylvian cortex supports syntactic and semantic resources for interpreting pronoun meaning in sentences. Second, a frontal-parietal network that supports strategic decision-making is recruited to support probabilistic and risk-related components of resolving a pronoun’s referent. In an fMRI study of healthy young adults, we observed activation of left inferior frontal and superior temporal cortex, consistent with a language network. We also observed activation of brain regions not associated with traditional language areas. By manipulating the context of the pronoun, we were able to demonstrate recruitment of dorsolateral prefrontal cortex during probabilistic evaluation of a pronoun’s reference, and orbital frontal activation when a pronoun must adopt a risky referent. Together, these findings are consistent with a two-component model for resolving a pronoun’s reference that includes neuroanatomic regions supporting core linguistic and decision-making mechanisms. PMID:22245014

Brain, Craniofacial, and Dental Lesions of a Free-ranging Gray Wolf (Canis lupus) Implicated in a Human Attack in Minnesota, USA.

PubMed

Schwabenlander, Marc; Stepaniuk, Kevin; Carstensen, Michelle; Armién, Aníbal G

2016-01-01

We describe significant brain, craniofacial, and dental lesions in a free-ranging wolf (Canis lupus) involved in a human attack. On postmortem examination, the wolf presented asymmetric atrophy and bone remodeling affecting the mandible, incisive, maxilla, lacrimal, palatine, frontal, and ethmoid bones. There was an asymmetrical skeletal malocclusion and dental abnormalities including rotated, malpositioned, partially erupted teeth, and an odontogenic cyst associated with an unerupted canine tooth. Brain changes were bilateral loss and atrophy of extensive cortex regions including olfactory bulb, peduncles, and tract, and the frontal lobe. We highlight the relevance of a thorough postmortem examination of wildlife to elucidate disease-based abnormal behavior as the reason for human-animal conflict.

A computational model of prefrontal control in free recall: strategic memory use in the California Verbal Learning Task.

PubMed

Becker, Suzanna; Lim, Jean

2003-08-15

Several decades of research into the function of the frontal lobes in brain-damaged patients, and more recently in intact individuals using function brain imaging, has delineated the complex executive functions of the frontal cortex. And yet, the mechanisms by which the brain achieves these functions remain poorly understood. Here, we present a computational model of the role of the prefrontal cortex (PFC) in controlled memory use that may help to shed light on the mechanisms underlying one aspect of frontal control: the development and deployment of recall strategies. The model accounts for interactions between the PFC and medial temporal lobe in strategic memory use. The PFC self-organizes its own mnemonic codes using internally derived performance measures. These mnemonic codes serve as retrieval cues by biasing retrieval in the medial temporal lobe memory system. We present data from three simulation experiments that demonstrate strategic encoding and retrieval in the free recall of categorized lists of words. Experiment 1 compares the performance of the model with two control networks to evaluate the contribution of various components of the model. Experiment 2 compares the performance of normal and frontally lesioned models to data from several studies using frontally intact and frontally lesioned individuals, as well as normal, healthy individuals under conditions of divided attention. Experiment 3 compares the model's performance on the recall of blocked and unblocked categorized lists of words to data from Stuss et al. (1994) for individuals with control and frontal lobe lesions. Overall, our model captures a number of aspects of human performance on free recall tasks: an increase in total words recalled and in semantic clustering scores across trials, superiority on blocked lists of related items compared to unblocked lists of related items, and similar patterns of performance across trials in the normal and frontally lesioned models, with poorer overall performance of the lesioned models on all measures. The model also has a number of shortcomings, in light of which we suggest extensions to the model that would enable more sophisticated forms of strategic control.

Region-specific changes in gene expression in rat brain after chronic treatment with levetiracetam or phenytoin

PubMed Central

Hassel, Bjørnar; Taubøll, Erik; Shaw, Renee; Gjerstad, Leif; Dingledine, Ray

2014-01-01

Summary Purpose It is commonly assumed that antiepileptic drugs (AEDs) act similarly in the various parts of the brain as long as their molecular targets are present. A few experimental studies on metabolic effects of vigabatrin, levetiracetam, valproate, and lamotrigine have shown that these drugs may act differently in different brain regions. We examined effects of chronic treatment with levetiracetam or phenytoin on mRNA levels to detect regional drug effects in a broad, nonbiased manner. Methods mRNA levels were monitored in three brain regions with oligonucleotide-based microarrays. Results Levetiracetam (150 mg/kg for 90 days) changed the expression of 65 genes in pons/medulla oblongata, two in hippocampus, and one in frontal cortex. Phenytoin (75 mg/kg), in contrast, changed the expression of only three genes in pons/medulla oblongata, but 64 genes in hippocampus, and 327 genes in frontal cortex. Very little overlap between regions or drug treatments was observed with respect to effects on gene expression. Discussion We conclude that chronic treatment with levetiracetam or phenytoin causes region-specific and highly differential effects on gene expression in the brain. Regional effects on gene expression could reflect regional differences in molecular targets of AEDs, and they could influence the clinical profiles of AEDs. PMID:20345932

Underlying neural mechanisms of mirror therapy: Implications for motor rehabilitation in stroke.

PubMed

Arya, Kamal Narayan

2016-01-01

Mirror therapy (MT) is a valuable method for enhancing motor recovery in poststroke hemiparesis. The technique utilizes the mirror-illusion created by the movement of sound limb that is perceived as the paretic limb. MT is a simple and economical technique than can stimulate the brain noninvasively. The intervention unquestionably has neural foundation. But the underlying neural mechanisms inducing motor recovery are still unclear. In this review, the neural-modulation due to MT has been explored. Multiple areas of the brain such as the occipital lobe, dorsal frontal area and corpus callosum are involved during the simple MT regime. Bilateral premotor cortex, primary motor cortex, primary somatosensory cortex, and cerebellum also get reorganized to enhance the function of the damaged brain. The motor areas of the lesioned hemisphere receive visuo-motor processing information through the parieto-occipital lobe. The damaged motor cortex responds variably to the MT and may augment true motor recovery. Mirror neurons may also play a possible role in the cortico-stimulatory mechanisms occurring due to the MT.

Synchronous Changes of Cortical Thickness and Corresponding White Matter Microstructure During Brain Development Accessed by Diffusion MRI Tractography from Parcellated Cortex

PubMed Central

Jeon, Tina; Mishra, Virendra; Ouyang, Minhui; Chen, Min; Huang, Hao

2015-01-01

Cortical thickness (CT) changes during normal brain development is associated with complicated cellular and molecular processes including synaptic pruning and apoptosis. In parallel, the microstructural enhancement of developmental white matter (WM) axons with their neuronal bodies in the cerebral cortex has been widely reported with measurements of metrics derived from diffusion tensor imaging (DTI), especially fractional anisotropy (FA). We hypothesized that the changes of CT and microstructural enhancement of corresponding axons are highly interacted during development. DTI and T1-weighted images of 50 healthy children and adolescents between the ages of 7 and 25 years were acquired. With the parcellated cortical gyri transformed from T1-weighted images to DTI space as the tractography seeds, probabilistic tracking was performed to delineate the WM fibers traced from specific parcellated cortical regions. CT was measured at certain cortical regions and FA was measured from the WM fibers traced from same cortical regions. The CT of all frontal cortical gyri, including Brodmann areas 4, 6, 8, 9, 10, 11, 44, 45, 46, and 47, decreased significantly and heterogeneously; concurrently, significant, and heterogeneous increases of FA of WM traced from corresponding regions were found. We further revealed significant correlation between the slopes of the CT decrease and the slopes of corresponding WM FA increase in all frontal cortical gyri, suggesting coherent cortical pruning and corresponding WM microstructural enhancement. Such correlation was not found in cortical regions other than frontal cortex. The molecular and cellular mechanisms of these synchronous changes may be associated with overlapping signaling pathways of axonal guidance, synaptic pruning, neuronal apoptosis, and more prevalent interstitial neurons in the prefrontal cortex. Revealing the coherence of cortical and WM structural changes during development may open a new window for understanding the underlying mechanisms of developing brain circuits and structural abnormality associated with mental disorders. PMID:26696839

Longitudinal in-vivo diffusion tensor imaging for assessing brain developmental changes in BALB/cJ mice, a model of reduced sociability relevant to autism.

PubMed

Kumar, Manoj; Kim, Sungheon; Pickup, Stephen; Chen, Rong; Fairless, Andrew H; Ittyerah, Ranjit; Abel, Ted; Brodkin, Edward S; Poptani, Harish

2012-05-21

Diffusion tensor imaging (DTI) is highly sensitive in detecting brain structure and connectivity phenotypes in autism spectrum disorders (ASD). Since one of the core symptoms of ASD is reduced sociability (reduced tendency to seek social interaction), we hypothesized that DTI will be sensitive in detecting neural phenotypes that correlate with decreased sociability in mouse models. Relative to C57BL/6J (B6) mice, juvenile BALB/cJ mice show reduced sociability. We performed social approach test in a three-chambered apparatus and in-vivo longitudinal DTI at post-natal days 30, 50 and 70 days-of-age in BALB/cJ (n=32) and B6 (n=15) mice to assess the correlation between DTI and sociability and to evaluate differences in DTI parameters between these two strains. Fractional anisotropy (FA) and mean diffusivity (MD) values from in-vivo DTI data were analyzed from white matter (corpus callosum, internal and external capsule) and gray matter (cerebral cortex, frontal motor cortex, hippocampus, thalamus and amygdaloid) regions based on their relevance to ASD. A moderate but significant (p<0.05) negative correlation between sociability and FA in hippocampus and frontal motor cortex was noted for BALB/cJ mice at 30 days-of-age. Significant differences in FA and MD values between BALB/cJ and B6 mice were observed in most white and gray matter areas at all three time points. Significant differences in developmental trajectories of FA and MD values from thalamus and frontal motor cortex were also observed between BALB/cJ and B6, indicating relative under-connectivity in BALB/cJ mice. These results indicate that DTI may be used as an in-vivo, non-invasive imaging method to assess developmental trajectories of brain connectivity in mouse models of neurodevelopmental and behavioral disorders. Copyright © 2012 Elsevier B.V. All rights reserved.

Longitudinal in-vivo diffusion tensor imaging for assessing brain developmental changes in BALB/cJ mice, a model of reduced sociability relevant to autism

PubMed Central

Kumar, Manoj; Kim, Sungheon; Pickup, Stephen; Chen, Rong; Fairless, Andrew H.; Ittyerah, Ranjit; Abel, Ted; Brodkin, Edward S.; Poptani, Harish

2012-01-01

Diffusion tensor imaging (DTI) is highly sensitive in detecting brain structure and connectivity phenotypes in autism spectrum disorders (ASD). Since one of the core symptoms of ASD is reduced sociability (reduced tendency to seek social interaction), we hypothesized that DTI will be sensitive in detecting neural phenotypes that correlate with decreased sociability in mouse models. Relative to C57BL/6J (B6) mice, juvenile BALB/cJ mice show reduced sociability. We performed social approach test in a three-chambered apparatus and in-vivo longitudinal DTI at post-natal days 30, 50 and 70 days-of-age in BALB/cJ (n=32) and B6 (n=15) mice to assess the correlation between DTI and sociability and to evaluate differences in DTI parameters between these two strains. Fractional anisotropy (FA) and mean diffusivity (MD) values from in-vivo DTI data were analyzed from white matter (corpus callosum, internal and external capsule) and gray matter (cerebral cortex, frontal motor cortex, hippocampus, thalamus and amygdaloid) regions based on their relevance to ASD. A moderate but significant (p<0.05) negative correlation between sociability and FA in hippocampus and frontal motor cortex was noted for BALB/cJ mice at 30 days-of-age. Significant differences in FA and MD values between BALB/cJ and B6 mice were observed in most white and gray matter areas at all three time points. Significant differences in developmental trajectories of FA and MD values from thalamus and frontal motor cortex were also observed between BALB/cJ and B6, indicating relative under-connectivity in BALB/cJ mice. These results indicate that DTI may be used as an in-vivo, non-invasive imaging method to assess developmental trajectories of brain connectivity in mouse models of neurodevelopmental and behavioral disorders. PMID:22513103

Chronic Social Stress and Ethanol Increase Expression of KLF11, a Cell Death Mediator, in Rat Brain.

PubMed

Duncan, Jeremy; Wang, Niping; Zhang, Xiao; Johnson, Shakevia; Harris, Sharonda; Zheng, Baoying; Zhang, Qinli; Rajkowska, Grazyna; Miguel-Hidalgo, Jose Javier; Sittman, Donald; Ou, Xiao-Ming; Stockmeier, Craig A; Wang, Jun Ming

2015-07-01

Major depressive disorder and alcoholism are significant health burdens that can affect executive functioning, cognitive ability, job responsibilities, and personal relationships. Studies in animal models related to depression or alcoholism reveal that the expression of Krüppel-like factor 11 (KLF11, also called TIEG2) is elevated in frontal cortex, which suggests that KLF11 may play a role in stress- or ethanol-induced psychiatric conditions. KLF11 is a transcriptional activator of monoamine oxidase A and B, but also serves other functions in cell cycle regulation and apoptotic cell death. In the present study, immunohistochemistry was used to quantify intensity of nuclear KLF11, combined with an unbiased stereological approach to assess nuclei in fronto-limbic, limbic, and other brain regions of rats exposed chronically to social defeat or ethanol. KLF11 immunoreactivity was increased significantly in the medial prefrontal cortex, frontal cortex, and hippocampus of both stressed rats and rats fed ethanol. However, expression of KLF11 protein was not significantly affected in the thalamus, hypothalamus, or amygdala in either treatment group compared to respective control rats. Triple-label immunofluorescence revealed that KLF11 protein was localized in nuclei of neurons and astrocytes. KLF11 was also co-localized with the immunoreactivity of cleaved caspase-3. In addition, Western blot analysis revealed a significant reduction in anti-apoptotic protein, Bcl-xL, but an increase of caspase-3 expression in the frontal cortex of ethanol-treated rats compared to ethanol-preferring controls. Thus, KLF11 protein is up-regulated following chronic exposure to stress or ethanol in a region-specific manner and may contribute to pro-apoptotic signaling in ethanol-treated rats. Further investigation into the KLF11 signaling cascade as a mechanism for neurotoxicity and cell death in depression and alcoholism may provide novel pharmacological targets to lessen brain damage and maximize neuroprotection in these disorders.

Re-Establishing Broca's Initial Findings

ERIC Educational Resources Information Center

Richardson, Jessica D.; Fillmore, Paul; Rorden, Chris; LaPointe, Leonard L.; Fridriksson, Julius

2012-01-01

The importance of the left inferior pre-frontal cortex (LIPC) for speech production was first popularized by Paul Broca, providing a cornerstone of behavioral neurology and laying the foundation for future research examining brain-behavior relationships. Although Broca's findings were rigorously challenged, comprehensive contradictory evidence was…

Brain structural covariance network centrality in maltreated youth with PTSD and in maltreated youth resilient to PTSD.

PubMed

Sun, Delin; Haswell, Courtney C; Morey, Rajendra A; De Bellis, Michael D

2018-04-10

Child maltreatment is a major cause of pediatric posttraumatic stress disorder (PTSD). Previous studies have not investigated potential differences in network architecture in maltreated youth with PTSD and those resilient to PTSD. High-resolution magnetic resonance imaging brain scans at 3 T were completed in maltreated youth with PTSD (n = 31), without PTSD (n = 32), and nonmaltreated controls (n = 57). Structural covariance network architecture was derived from between-subject intraregional correlations in measures of cortical thickness in 148 cortical regions (nodes). Interregional positive partial correlations controlling for demographic variables were assessed, and those correlations that exceeded specified thresholds constituted connections in cortical brain networks. Four measures of network centrality characterized topology, and the importance of cortical regions (nodes) within the network architecture were calculated for each group. Permutation testing and principle component analysis method were employed to calculate between-group differences. Principle component analysis is a methodological improvement to methods used in previous brain structural covariance network studies. Differences in centrality were observed between groups. Larger centrality was found in maltreated youth with PTSD in the right posterior cingulate cortex; smaller centrality was detected in the right inferior frontal cortex compared to youth resilient to PTSD and controls, demonstrating network characteristics unique to pediatric maltreatment-related PTSD. Larger centrality was detected in right frontal pole in maltreated youth resilient to PTSD compared to youth with PTSD and controls, demonstrating structural covariance network differences in youth resilience to PTSD following maltreatment. Smaller centrality was found in the left posterior cingulate cortex and in the right inferior frontal cortex in maltreated youth compared to controls, demonstrating attributes of structural covariance network topology that is unique to experiencing maltreatment. This work is the first to identify cortical thickness-based structural covariance network differences between maltreated youth with and without PTSD. We demonstrated network differences in both networks unique to maltreated youth with PTSD and those resilient to PTSD. The networks identified are important for the successful attainment of age-appropriate social cognition, attention, emotional processing, and inhibitory control. Our findings in maltreated youth with PTSD versus those without PTSD suggest vulnerability mechanisms for developing PTSD.

SU-E-I-34: Intermittent Low- and High-Dose Ethanol Exposure Alters Neurochemical Responses in Adult Rat Brain: An Ex Vivo 1H NMR Spectroscopy at 11.7 T

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Do-Wan; Kim, Sang-Young; Song, Kyu-Ho

Purpose: The first goal of this study was to determine the influence of the dose-dependent effects of intermittent ethanol intoxication on cerebral neurochemical responses among sham controls and low- and high-dose-ethanol-exposed rats with ex vivo high-resolution spectra. The second goal of this study was to determine the correlations between the metabolite-metabolite levels (pairs-of-metabolite levels) from all of the individual data from the frontal cortex of the intermittent ethanol-intoxicated rats. Methods: Eight-week-old male Wistar rats were divided into 3 groups. Twenty rats in the LDE (n = 10) and the HDE (n = 10) groups received ethanol doses of 1.5 g/kgmore » and 2.5 g/kg, respectively, through oral gavage every 8-h for 4 days. At the end of the 4-day intermittent ethanol exposure, one-dimensional ex vivo 500-MHz proton nuclear magnetic resonance spectra were acquired from 30 samples of the frontal cortex region (from the 3 groups). Results: Normalized total-N-acetylaspartate (tNAA: NAA + NAAG [N-acetylaspartyl-glutamate]), gamma-aminobutyric acid (GABA), and glutathione (GSH) levels were significantly lower in the frontal cortex of the HDE-exposed rats than that of the LDE-exposed rats. Moreover, compared to the CNTL group, the LDE rats exhibited significantly higher normalized GABA levels. The 6 pairs of normalized metabolite levels were positively (+) or negatively (−) correlated in the rat frontal cortex as follows: tNAA and GABA (+), tNAA and Aspartate (Asp) (−), myo-Inositol (mIns) and Asp (−), mIns and Alanine (+), mIns and Taurine (+), and mIns and tNAA (−). Conclusion: Our results suggested that repeated intermittent ethanol intoxication might result in neuronal degeneration and dysfunction, changes in the rate of GABA synthesis, and oxidative stress in the rat frontal cortex. Our ex vivo 1H high-resolution-magic angle spinning nuclear magnetic resonance spectroscopy results suggested some novel metabolic markers for the dose-dependent influence of repeated intermittent ethanol intoxication in the frontal cortex.« less

Identifying minimal hepatic encephalopathy in cirrhotic patients by measuring spontaneous brain activity.

PubMed

Chen, Hua-Jun; Zhang, Ling; Jiang, Long-Feng; Chen, Qiu-Feng; Li, Jun; Shi, Hai-Bin

2016-08-01

It has been demonstrated that minimal hepatic encephalopathy (MHE) is associated with aberrant regional intrinsic brain activity in cirrhotic patients. However, few studies have investigated whether altered intrinsic brain activity can be used as a biomarker of MHE among cirrhotic patients. In this study, 36 cirrhotic patients (with MHE, n = 16; without MHE [NHE], n = 20) underwent resting-state functional magnetic resonance imaging (fMRI). Spontaneous brain activity was measured by examining the amplitude of low-frequency fluctuations (ALFF) in the fMRI signal. MHE was diagnosed based on the Psychometric Hepatic Encephalopathy Score (PHES). A two-sample t-test was used to determine the regions of interest (ROIs) in which ALFF differed significantly between the two groups; then, ALFF values within ROIs were selected as classification features. A linear discriminative analysis was used to differentiate MHE patients from NHE patients. The leave-one-out cross-validation method was used to estimate the performance of the classifier. The classification analysis was 80.6 % accurate (81.3 % sensitivity and 80.0 % specificity) in terms of distinguishing between the two groups. Six ROIs were identified as the most discriminative features, including the bilateral medial frontal cortex/anterior cingulate cortex, posterior cingulate cortex/precuneus, left precentral and postcentral gyrus, right lingual gyrus, middle frontal gyrus, and inferior/superior parietal lobule. The ALFF values within ROIs were correlated with PHES in cirrhotic patients. Our findings suggest that altered regional brain spontaneous activity is a useful biomarker for MHE detection among cirrhotic patients.

Neuroprotective effect of ebselen against intracerebroventricular streptozotocin-induced neuronal apoptosis and oxidative stress in rats.

PubMed

Unsal, Cuneyt; Oran, Mustafa; Albayrak, Yakup; Aktas, Cevat; Erboga, Mustafa; Topcu, Birol; Uygur, Ramazan; Tulubas, Feti; Yanartas, Omer; Ates, Ozkan; Ozen, Oguz Aslan

2016-04-01

The goal of this study was to examine the neuroprotective effect of ebselen against intracerebroventricular streptozotocin (ICV-STZ)-induced oxidative stress and neuronal apoptosis in rat brain. A total of 30 adult male Sprague-Dawley rats were randomly divided into 3 groups of 10 animals each: control, ICV-STZ, and ICV-STZ treated with ebselen. The ICV-STZ group rats were injected bilaterally with ICV-STZ (3 mg/kg) on days 1 and 3, and ebselen (10 mg/kg/day) was administered for 14 days starting from 1st day of ICV-STZ injection to day 14. Rats were killed at the end of the study and brain tissues were removed for biochemical and histopathological investigation. Our results demonstrated, for the first time, the neuroprotective effect of ebselen on Alzheimer's disease (AD) model in rats. Our present study, in ICV-STZ group, showed significant increase in tissue malondialdehyde levels and significant decrease in enzymatic antioxidants superoxide dismutase and glutathione peroxidase in the frontal cortex tissue. The histopathological studies in the brain of rats also supported that ebselen markedly reduced the ICV-STZ-induced histopathological changes and well preserved the normal histological architecture of the frontal cortex tissue. The number of apoptotic neurons was increased in frontal cortex tissue after ICV-STZ administration. Treatment of ebselen markedly reduced the number of degenerating apoptotic neurons. The study demonstrates the effectiveness of ebselen, as a powerful antioxidant, in preventing the oxidative damage and morphological changes caused by ICV-STZ in rats. Thus, ebselen may have a therapeutic value for the treatment of AD. © The Author(s) 2013.

The Brain Functional Networks Associated to Human and Animal Suffering Differ among Omnivores, Vegetarians and Vegans

PubMed Central

Filippi, Massimo; Riccitelli, Gianna; Falini, Andrea; Di Salle, Francesco; Vuilleumier, Patrik; Comi, Giancarlo; Rocca, Maria A.

2010-01-01

Empathy and affective appraisals for conspecifics are among the hallmarks of social interaction. Using functional MRI, we hypothesized that vegetarians and vegans, who made their feeding choice for ethical reasons, might show brain responses to conditions of suffering involving humans or animals different from omnivores. We recruited 20 omnivore subjects, 19 vegetarians, and 21 vegans. The groups were matched for sex and age. Brain activation was investigated using fMRI and an event-related design during observation of negative affective pictures of human beings and animals (showing mutilations, murdered people, human/animal threat, tortures, wounds, etc.). Participants saw negative-valence scenes related to humans and animals, alternating with natural landscapes. During human negative valence scenes, compared with omnivores, vegetarians and vegans had an increased recruitment of the anterior cingulate cortex (ACC) and inferior frontal gyrus (IFG). More critically, during animal negative valence scenes, they had decreased amygdala activation and increased activation of the lingual gyri, the left cuneus, the posterior cingulate cortex and several areas mainly located in the frontal lobes, including the ACC, the IFG and the middle frontal gyrus. Nonetheless, also substantial differences between vegetarians and vegans have been found responding to negative scenes. Vegetarians showed a selective recruitment of the right inferior parietal lobule during human negative scenes, and a prevailing activation of the ACC during animal negative scenes. Conversely, during animal negative scenes an increased activation of the inferior prefrontal cortex was observed in vegans. These results suggest that empathy toward non conspecifics has different neural representation among individuals with different feeding habits, perhaps reflecting different motivational factors and beliefs. PMID:20520767

Grammatical distinctions in the left frontal cortex.

PubMed

Shapiro, K A; Pascual-Leone, A; Mottaghy, F M; Gangitano, M; Caramazza, A

2001-08-15

Selective deficits in producing verbs relative to nouns in speech are well documented in neuropsychology and have been associated with left hemisphere frontal cortical lesions resulting from stroke and other neurological disorders. The basis for these impairments is unresolved: Do they arise because of differences in the way grammatical categories of words are organized in the brain, or because of differences in the neural representation of actions and objects? We used repetitive transcranial magnetic stimulation (rTMS) to suppress the excitability of a portion of left prefrontal cortex and to assess its role in producing nouns and verbs. In one experiment subjects generated real words; in a second, they produced pseudowords as nouns or verbs. In both experiments, response latencies increased for verbs but were unaffected for nouns following rTMS. These results demonstrate that grammatical categories have a neuroanatomical basis and that the left prefrontal cortex is selectively engaged in processing verbs as grammatical objects.

Convergence of EEG and fMRI measures of reward anticipation.

PubMed

Gorka, Stephanie M; Phan, K Luan; Shankman, Stewart A

2015-12-01

Deficits in reward anticipation are putative mechanisms for multiple psychopathologies. Research indicates that these deficits are characterized by reduced left (relative to right) frontal electroencephalogram (EEG) activity and blood oxygenation level-dependent (BOLD) signal abnormalities in mesolimbic and prefrontal neural regions during reward anticipation. Although it is often assumed that these two measures capture similar mechanisms, no study to our knowledge has directly examined the convergence between frontal EEG alpha asymmetry and functional magnetic resonance imaging (fMRI) during reward anticipation in the same sample. Therefore, the aim of the current study was to investigate if and where in the brain frontal EEG alpha asymmetry and fMRI measures were correlated in a sample of 40 adults. All participants completed two analogous reward anticipation tasks--once during EEG data collection and the other during fMRI data collection. Results indicated that the two measures do converge and that during reward anticipation, increased relative left frontal activity is associated with increased left anterior cingulate cortex (ACC)/medial prefrontal cortex (mPFC) and left orbitofrontal cortex (OFC) activation. This suggests that the two measures may similarly capture PFC functioning, which is noteworthy given the role of these regions in reward processing and the pathophysiology of disorders such as depression and schizophrenia. Copyright © 2015 Elsevier B.V. All rights reserved.

The Neural Correlates of Chronic Symptoms of Vertigo Proneness in Humans

PubMed Central

Alsalman, Ola; Ost, Jan; Vanspauwen, Robby; Blaivie, Catherine; De Ridder, Dirk; Vanneste, Sven

2016-01-01

Vestibular signals are of significant importance for variable functions including gaze stabilization, spatial perception, navigation, cognition, and bodily self-consciousness. The vestibular network governs functions that might be impaired in patients affected with vestibular dysfunction. It is currently unclear how different brain regions/networks process vestibular information and integrate the information into a unified spatial percept related to somatosensory awareness and whether people with recurrent balance complaints have a neural signature as a trait affecting their development of chronic symptoms of vertigo. Pivotal evidence points to a vestibular-related brain network in humans that is widely distributed in nature. By using resting state source localized electroencephalography in non-vertiginous state, electrophysiological changes in activity and functional connectivity of 23 patients with balance complaints where chronic symptoms of vertigo and dizziness are among the most common reported complaints are analyzed and compared to healthy subjects. The analyses showed increased alpha2 activity within the posterior cingulate cortex and the precuneues/cuneus and reduced beta3 and gamma activity within the pregenual and subgenual anterior cingulate cortex for the subjects with balance complaints. These electrophysiological variations were correlated with reported chronic symptoms of vertigo intensity. A region of interest analysis found reduced functional connectivity for gamma activity within the vestibular cortex, precuneus, frontal eye field, intra-parietal sulcus, orbitofrontal cortex, and the dorsal anterior cingulate cortex. In addition, there was a positive correlation between chronic symptoms of vertigo intensity and increased alpha-gamma nesting in the left frontal eye field. When compared to healthy subjects, there is evidence of electrophysiological changes in the brain of patients with balance complaints even outside chronic symptoms of vertigo episodes. This suggests that these patients have a neural signature or trait that makes them prone to developing chronic balance problems. PMID:27089185

[A case of MM1+2 Creutzfeldt-Jakob disease with a longitudinal study of EEG and MRI].

PubMed

Katsube, Mizuho; Shiota, Yuri; Harada, Takayuki; Shibata, Hiroshi; Nagai, Atsushi

2013-11-01

We report a case of definite MM1 + 2 sporadic Creutzfeldt-Jakob disease (sCJD). A 66-year-old woman was admitted to our hospital with memory disturbance and disorientation for three months. On admission she presented a progressive cognitive insufficiency. Electroencephalography (EEG) revealed a frontal intermittent rhythmical delta activity (FIRDA) and the brain magnetic resonance imaging (MRI) showed high signal intensities in cerebral cortex on diffusion weighted images (DWI). After four months from the onset, she reached the akinetic mutism state followed by myoclonus. Follow up examination revealed that periodic synchronous discharge (PSD) was found in EEG, and DWI revealed enlargement of high signal intensity lesions in cerebral cortex. At seven months from the onset, PSD and high signal intensities of cortex became unclear with disappearance of myoclonus, and brain white matter lesions were evident on MRI. Serial studies of EEG and MRI revealed that PSD generalized from frontal lobe dominant pattern, while high signal intensity lesions of cortex diffusely increased on DWI. At ten months from the onset patient died. Pathological examination in brain showed moderate and diffuse neuronal cell loss and gliosis in cerebral cortex corresponding with DWI changes. The genotype at codon 129 of the prion protein (PrP) was homozygous methionine (MM) and the type of protease-resistant PrP (PrPres) was the mixed type of 1 and 2 in Western blot analysis. It has been rare to analyze the changes of EEG and MRI in the entire stage and to investigate pathological finding in the case of sCJD-MM1 + 2. A longitudinal examination of EEG and MRI is useful for early diagnosis of CJD. Also we could correlate these findings with clinical and histopathological phenotype.

The Neural Correlates of Chronic Symptoms of Vertigo Proneness in Humans.

PubMed

Alsalman, Ola; Ost, Jan; Vanspauwen, Robby; Blaivie, Catherine; De Ridder, Dirk; Vanneste, Sven

2016-01-01

Vestibular signals are of significant importance for variable functions including gaze stabilization, spatial perception, navigation, cognition, and bodily self-consciousness. The vestibular network governs functions that might be impaired in patients affected with vestibular dysfunction. It is currently unclear how different brain regions/networks process vestibular information and integrate the information into a unified spatial percept related to somatosensory awareness and whether people with recurrent balance complaints have a neural signature as a trait affecting their development of chronic symptoms of vertigo. Pivotal evidence points to a vestibular-related brain network in humans that is widely distributed in nature. By using resting state source localized electroencephalography in non-vertiginous state, electrophysiological changes in activity and functional connectivity of 23 patients with balance complaints where chronic symptoms of vertigo and dizziness are among the most common reported complaints are analyzed and compared to healthy subjects. The analyses showed increased alpha2 activity within the posterior cingulate cortex and the precuneues/cuneus and reduced beta3 and gamma activity within the pregenual and subgenual anterior cingulate cortex for the subjects with balance complaints. These electrophysiological variations were correlated with reported chronic symptoms of vertigo intensity. A region of interest analysis found reduced functional connectivity for gamma activity within the vestibular cortex, precuneus, frontal eye field, intra-parietal sulcus, orbitofrontal cortex, and the dorsal anterior cingulate cortex. In addition, there was a positive correlation between chronic symptoms of vertigo intensity and increased alpha-gamma nesting in the left frontal eye field. When compared to healthy subjects, there is evidence of electrophysiological changes in the brain of patients with balance complaints even outside chronic symptoms of vertigo episodes. This suggests that these patients have a neural signature or trait that makes them prone to developing chronic balance problems.

Restless 'rest': intrinsic sensory hyperactivity and disinhibition in post-traumatic stress disorder.

PubMed

Clancy, Kevin; Ding, Mingzhou; Bernat, Edward; Schmidt, Norman B; Li, Wen

2017-07-01

Post-traumatic stress disorder is characterized by exaggerated threat response, and theoretical accounts to date have focused on impaired threat processing and dysregulated prefrontal-cortex-amygdala circuitry. Nevertheless, evidence is accruing for broad, threat-neutral sensory hyperactivity in post-traumatic stress disorder. As low-level, sensory processing impacts higher-order operations, such sensory anomalies can contribute to widespread dysfunctions, presenting an additional aetiological mechanism for post-traumatic stress disorder. To elucidate a sensory pathology of post-traumatic stress disorder, we examined intrinsic visual cortical activity (based on posterior alpha oscillations) and bottom-up sensory-driven causal connectivity (Granger causality in the alpha band) during a resting state (eyes open) and a passive, serial picture viewing state. Compared to patients with generalized anxiety disorder (n = 24) and healthy control subjects (n = 20), patients with post-traumatic stress disorder (n = 25) demonstrated intrinsic sensory hyperactivity (suppressed posterior alpha power, source-localized to the visual cortex-cuneus and precuneus) and bottom-up inhibition deficits (reduced posterior→frontal Granger causality). As sensory input increased from resting to passive picture viewing, patients with post-traumatic stress disorder failed to demonstrate alpha adaptation, highlighting a rigid, set mode of sensory hyperactivity. Interestingly, patients with post-traumatic stress disorder also showed heightened frontal processing (augmented frontal gamma power, source-localized to the superior frontal gyrus and dorsal cingulate cortex), accompanied by attenuated top-down inhibition (reduced frontal→posterior causality). Importantly, not only did suppressed alpha power and bottom-up causality correlate with heightened frontal gamma power, they also correlated with increased severity of sensory and executive dysfunctions (i.e. hypervigilance and impulse control deficits, respectively). Therefore, sensory aberrations help construct a vicious cycle in post-traumatic stress disorder that is in action even at rest, implicating dysregulated triangular sensory-prefrontal-cortex-amygdala circuitry: intrinsic sensory hyperactivity and disinhibition give rise to frontal overload and disrupt executive control, fuelling and perpetuating post-traumatic stress disorder symptoms. Absent in generalized anxiety disorder, these aberrations highlight a unique sensory pathology of post-traumatic stress disorder (ruling out effects merely reflecting anxious hyperarousal), motivating new interventions targeting sensory processing and the sensory brain in these patients. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Preliminary evidence of white matter abnormality in the uncinate fasciculus in generalized social anxiety disorder.

PubMed

Phan, K Luan; Orlichenko, Anton; Boyd, Erin; Angstadt, Mike; Coccaro, Emil F; Liberzon, Israel; Arfanakis, Konstantinos

2009-10-01

Individuals with generalized social anxiety disorder (GSAD) exhibit exaggerated amygdala reactivity to aversive social stimuli. These findings could be explained by microstructural abnormalities in white matter (WM) tracts that connect the amygdala and prefrontal cortex, which is known to modulate the amygdala's response to threat. The goal of this study was to investigate brain frontal WM abnormalities using diffusion tensor imaging (DTI) in patients with social anxiety disorder. A Turboprop DTI sequence was used to acquire diffusion tensor images in 30 patients with GSAD and 30 matched healthy control subjects. Fractional anisotropy, an index of axonal organization, within WM was quantified in individual subjects, and an automated voxel-based, whole-brain method was used to analyze group differences. Compared with healthy control subjects, patients had significantly lower fractional anisotropy localized to the right uncinate fasciculus WM near the orbitofrontal cortex. There were no areas of higher fractional anisotropy in patients than controls. These findings point to an abnormality in the uncinate fasciculus, the major WM tract connecting the frontal cortex to the amygdala and other limbic temporal regions, in GSAD, which could underlie the aberrant amygdala-prefrontal interactions resulting in dysfunctional social threat processing in this illness.

Changes in Neural Connectivity and Memory Following a Yoga Intervention for Older Adults: A Pilot Study.

PubMed

Eyre, Harris A; Acevedo, Bianca; Yang, Hongyu; Siddarth, Prabha; Van Dyk, Kathleen; Ercoli, Linda; Leaver, Amber M; Cyr, Natalie St; Narr, Katherine; Baune, Bernhard T; Khalsa, Dharma S; Lavretsky, Helen

2016-01-01

No study has explored the effect of yoga on cognitive decline and resting-state functional connectivity. This study explored the relationship between performance on memory tests and resting-state functional connectivity before and after a yoga intervention versus active control for subjects with mild cognitive impairment (MCI). Participants ( ≥ 55 y) with MCI were randomized to receive a yoga intervention or active "gold-standard" control (i.e., memory enhancement training (MET)) for 12 weeks. Resting-state functional magnetic resonance imaging was used to map correlations between brain networks and memory performance changes over time. Default mode networks (DMN), language and superior parietal networks were chosen as networks of interest to analyze the association with changes in verbal and visuospatial memory performance. Fourteen yoga and 11 MET participants completed the study. The yoga group demonstrated a statistically significant improvement in depression and visuospatial memory. We observed improved verbal memory performance correlated with increased connectivity between the DMN and frontal medial cortex, pregenual anterior cingulate cortex, right middle frontal cortex, posterior cingulate cortex, and left lateral occipital cortex. Improved verbal memory performance positively correlated with increased connectivity between the language processing network and the left inferior frontal gyrus. Improved visuospatial memory performance correlated inversely with connectivity between the superior parietal network and the medial parietal cortex. Yoga may be as effective as MET in improving functional connectivity in relation to verbal memory performance. These findings should be confirmed in larger prospective studies.

Working Memory Performance Is Correlated with Local Brain Morphology in the Medial Frontal and Anterior Cingulate Cortex in Fibromyalgia Patients: Structural Correlates of Pain-Cognition Interaction

ERIC Educational Resources Information Center

Luerding, R.; Weigand, T.; Bogdahn, U.; Schmidt-Wilcke, T.

2008-01-01

Fibromyalgia (FM) is a disorder of unknown aetiology, characterized by chronic widespread pain, stiffness and sleep disturbances. In addition, patients frequently complain of memory and attention deficits. Accumulating evidence suggests that FM is associated with CNS dysfunction and with an altered brain morphology. However, few studies have…

Semantic strategy training increases memory performance and brain activity in patients with prefrontal cortex lesions.

PubMed

Miotto, Eliane C; Savage, Cary R; Evans, Jonathan J; Wilson, Barbara A; Martin, Maria G M; Balardin, Joana B; Barros, Fabio G; Garrido, Griselda; Teixeira, Manoel J; Amaro Junior, Edson

2013-03-01

Memory deficit is a frequent cognitive disorder following acquired prefrontal cortex lesions. In the present study, we investigated the brain correlates of a short semantic strategy training and memory performance of patients with distinct prefrontal cortex lesions using fMRI and cognitive tests. Twenty-one adult patients with post-acute prefrontal cortex (PFC) lesions, twelve with left dorsolateral PFC (LPFC) and nine with bilateral orbitofrontal cortex (BOFC) were assessed before and after a short cognitive semantic training using a verbal memory encoding paradigm during scanning and neuropsychological tests outside the scanner. After the semantic strategy training both groups of patients showed significant behavioral improvement in verbal memory recall and use of semantic strategies. In the LPFC group, greater activity in left inferior and medial frontal gyrus, precentral gyrus and insula was found after training. For the BOFC group, a greater activation was found in the left parietal cortex, right cingulated and precuneus after training. The activation of these specific areas in the memory and executive networks following cognitive training was associated to compensatory brain mechanisms and application of the semantic strategy. Copyright © 2012 Elsevier B.V. All rights reserved.

Functional MRI of the vocalization-processing network in the macaque brain

PubMed Central

Ortiz-Rios, Michael; Kuśmierek, Paweł; DeWitt, Iain; Archakov, Denis; Azevedo, Frederico A. C.; Sams, Mikko; Jääskeläinen, Iiro P.; Keliris, Georgios A.; Rauschecker, Josef P.

2015-01-01

Using functional magnetic resonance imaging in awake behaving monkeys we investigated how species-specific vocalizations are represented in auditory and auditory-related regions of the macaque brain. We found clusters of active voxels along the ascending auditory pathway that responded to various types of complex sounds: inferior colliculus (IC), medial geniculate nucleus (MGN), auditory core, belt, and parabelt cortex, and other parts of the superior temporal gyrus (STG) and sulcus (STS). Regions sensitive to monkey calls were most prevalent in the anterior STG, but some clusters were also found in frontal and parietal cortex on the basis of comparisons between responses to calls and environmental sounds. Surprisingly, we found that spectrotemporal control sounds derived from the monkey calls (“scrambled calls”) also activated the parietal and frontal regions. Taken together, our results demonstrate that species-specific vocalizations in rhesus monkeys activate preferentially the auditory ventral stream, and in particular areas of the antero-lateral belt and parabelt. PMID:25883546

Influence of posterior dental arch length on brain activity during chewing in patients with mandibular distal extension removable partial dentures.

PubMed

Shoi, K; Fueki, K; Usui, N; Taira, M; Wakabayashi, N

2014-07-01

It is well known that shortened dental arch decreases masticatory function. However, its potential to change brain activity during mastication is unknown. The present study investigates the effect of a shortened posterior dental arch with mandibular removable partial dentures (RPDs) on brain activity during gum chewing. Eleven subjects with missing mandibular molars (mean age, 66.1 years) on both sides received experimental RPDs with interchangeable artificial molars in a crossover trial design. Brain activity during gum chewing with RPDs containing (full dental arch) and lacking artificial molars (shortened dental arch) was measured using functional magnetic resonance imaging. Additionally, masticatory function was evaluated for each dental arch type. Food comminuting and mixing ability and the perceived chewing ability were significantly lower in subjects with a shortened dental arch than those with a full dental arch (P < 0.05). Brain activation during gum chewing with the full dental arch occurred in the middle frontal gyrus, primary sensorimotor cortex extending to the pre-central gyrus, supplementary motor area, putamen, insula and cerebellum. However, middle frontal gyrus activation was not observed during gum chewing with the shortened dental arch. These results suggest that shortened dental arch affects human brain activity in the middle frontal gyrus during gum chewing, and the decreased middle frontal gyrus activation may be associated with decreased masticatory function. © 2014 John Wiley & Sons Ltd.

Dysfunction in Fatty Acid Amide Hydrolase Is Associated with Depressive-Like Behavior in Wistar Kyoto Rats

PubMed Central

Vinod, K. Yaragudri; Xie, Shan; Psychoyos, Delphine; Hungund, Basalingappa L.; Cooper, Thomas B.; Tejani-Butt, Shanaz M.

2012-01-01

Background While the etiology of depression is not clearly understood at the present time, this mental disorder is thought be a complex and multifactorial trait with important genetic and environmental contributing factors. Methodology/Principal Findings The role of the endocannabinoid (eCB) system in depressive behavior was examined in Wistar Kyoto (WKY) rat strain, a genetic model of depression. Our findings revealed selective abnormalities in the eCB system in the brains of WKY rats compared to Wistar (WIS) rats. Immunoblot analysis indicated significantly higher levels of fatty acid amide hydrolase (FAAH) in frontal cortex and hippocampus of WKY rats with no alteration in the level of N-arachidonyl phosphatidyl ethanolamine specific phospholipase-D (NAPE-PLD). Significantly higher levels of CB1 receptor-mediated G-protein coupling and lower levels of anandamide (AEA) were found in frontal cortex and hippocampus of WKY rats. While the levels of brain derived neurotropic factor (BDNF) were significantly lower in frontal cortex and hippocampus of WKY rats compared to WIS rats, pharmacological inhibition of FAAH elevated BDNF levels in WKY rats. Inhibition of FAAH enzyme also significantly increased sucrose consumption and decreased immobility in the forced swim test in WKY rats. Conclusions/Significance These findings suggest a critical role for the eCB system and BDNF in the genetic predisposition to depressive-like behavior in WKY rats and point to the potential therapeutic utility of eCB enhancing agents in depressive disorder. PMID:22606285

Dysfunction in fatty acid amide hydrolase is associated with depressive-like behavior in Wistar Kyoto rats.

PubMed

Vinod, K Yaragudri; Xie, Shan; Psychoyos, Delphine; Hungund, Basalingappa L; Cooper, Thomas B; Tejani-Butt, Shanaz M

2012-01-01

While the etiology of depression is not clearly understood at the present time, this mental disorder is thought be a complex and multifactorial trait with important genetic and environmental contributing factors. The role of the endocannabinoid (eCB) system in depressive behavior was examined in Wistar Kyoto (WKY) rat strain, a genetic model of depression. Our findings revealed selective abnormalities in the eCB system in the brains of WKY rats compared to Wistar (WIS) rats. Immunoblot analysis indicated significantly higher levels of fatty acid amide hydrolase (FAAH) in frontal cortex and hippocampus of WKY rats with no alteration in the level of N-arachidonyl phosphatidyl ethanolamine specific phospholipase-D (NAPE-PLD). Significantly higher levels of CB1 receptor-mediated G-protein coupling and lower levels of anandamide (AEA) were found in frontal cortex and hippocampus of WKY rats. While the levels of brain derived neurotropic factor (BDNF) were significantly lower in frontal cortex and hippocampus of WKY rats compared to WIS rats, pharmacological inhibition of FAAH elevated BDNF levels in WKY rats. Inhibition of FAAH enzyme also significantly increased sucrose consumption and decreased immobility in the forced swim test in WKY rats. These findings suggest a critical role for the eCB system and BDNF in the genetic predisposition to depressive-like behavior in WKY rats and point to the potential therapeutic utility of eCB enhancing agents in depressive disorder.

Interfering with the neural activity of mirror-related frontal areas impairs mentalistic inferences.

PubMed

Herbet, Guillaume; Lafargue, Gilles; Moritz-Gasser, Sylvie; Bonnetblanc, François; Duffau, Hugues

2015-07-01

According to recently proposed interactive dual-process theories, mentalizing abilities emerge from the coherent interaction between two physically distinct neural systems: (1) the mirror network, coding for the low-level embodied representations involved in pre-reflective sociocognitive processes and (2) the mentalizing network per se, which codes for higher level representations subtending the reflective attribution of psychological states. However, although the latest studies have shown that the core areas forming these two neurocognitive systems do indeed maintain effective connectivity during mentalizing, it is unclear whether an intact mirror system (and, more specifically, its anterior node, namely the posterior inferior frontal cortex) is a prerequisite for accurate mentalistic inferences. Intraoperative brain mapping via direct electrical stimulation offers a unique opportunity to address this issue. Electrical stimulation of the brain creates a "virtual" lesion, which provides functional information on well-defined parts of the cerebral cortex. In the present study, five patients were mapped in real time while they performed a mentalizing task. We found six responsive sites: four in the lateral part of the right pars opercularis and two in the dorsal part of the right pars triangularis. On the subcortical level, two additional sites were located within the white matter connectivity of the pars opercularis. Taken as a whole, our results suggest that the right inferior frontal cortex and its underlying axonal connectivity have a key role in mentalizing. Specifically, our findings support the hypothesis whereby transient, functional disruption of the mirror network influences higher order mentalistic inferences.

[Visuoperceptual processing in Parkinson's disease: from the retina to the frontal cortex].

PubMed

Ruiz-Sánchez de León, J M; Fernández-Guinea, S

The growing interest in the cognitive impairment shown by patients with Parkinson's disease has led to a wealth of research in this line over recent years. In this paper we review the visuospatial alterations in these patients, which are usually linked to other disorders such as those affecting planning, sequencing, attention or mnemonic processes. We report the most relevant findings, which suggest that the existence of these visuospatial disorders shown by patients with Parkinson's disease are not always secondary to other frontal-type cognitive impairments, as has been claimed in recent years. Instead, they may be due to disorders in other anterior points of the perceptive process (as a result of dopaminergic deficits in basal-thalamic-cortical circuits). Thus, visuoperceptual disorders are classified according to their location in the brain: from the retina to the lateral geniculate nucleus, the visual cortex and the extrastriate cortex and, finally, the frontal and prefrontal cortex. We propose this classification of the disorders according to their location to aid in achieving an objective selection of the sample and of the neuropsychological tests used in studies. In this regard, we consider that there should be a higher degree of agreement among researchers when it comes to designing research projects that deal with visuospatial disorders in patients with Parkinson's disease.

Attribution of emotions to body postures: an independent component analysis study of functional connectivity in autism.

PubMed

Libero, Lauren E; Stevens, Carl E; Kana, Rajesh K

2014-10-01

The ability to interpret others' body language is a vital skill that helps us infer their thoughts and emotions. However, individuals with autism spectrum disorder (ASD) have been found to have difficulty in understanding the meaning of people's body language, perhaps leading to an overarching deficit in processing emotions. The current fMRI study investigates the functional connectivity underlying emotion and action judgment in the context of processing body language in high-functioning adolescents and young adults with autism, using an independent components analysis (ICA) of the fMRI time series. While there were no reliable group differences in brain activity, the ICA revealed significant involvement of occipital and parietal regions in processing body actions; and inferior frontal gyrus, superior medial prefrontal cortex, and occipital cortex in body expressions of emotions. In a between-group analysis, participants with autism, relative to typical controls, demonstrated significantly reduced temporal coherence in left ventral premotor cortex and right superior parietal lobule while processing emotions. Participants with ASD, on the other hand, showed increased temporal coherence in left fusiform gyrus while inferring emotions from body postures. Finally, a positive predictive relationship was found between empathizing ability and the brain areas underlying emotion processing in ASD participants. These results underscore the differential role of frontal and parietal brain regions in processing emotional body language in autism. Copyright © 2014 Wiley Periodicals, Inc.

In vivo binding of /sup 125/I-LSD to serotonin 5-HT/sub 2/ receptors in mouse brain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartig, P.R.; Scheffel, U., Frost, J.J.; Wagner, H.N. Jr.

The binding of /sup 125/I-LSD (2-(/sup 125/I)-lysergic acid diethylamide) was studied in various mouse brain regions following intravenous injection of the radioligand. The high specific activity of /sup 125/I-LSD enabled the injection of low mass doses (14ng/kg), which are well below the threshold for induction of any known physiological effect of the probe. The highest levels of /sup 125/I-LSD binding were found in the frontal cortex, olfactory tubercles, extra-frontal cortex and striatum while the lowest level was found in the cerebellum. Binding was saturable in the frontal cortex but increased linearly in the cerebellum with increasing doses of /sup 125/I-LSD.more » Serotonergic compounds potently inhibited /sup 125/I-LSD binding in cortical regions, olfactory tubercles, and hypothalamus but had no effect in the cerebellum. Dopaminergic compounds caused partial inhibition of binding in the striatum while adrenergic compounds were inactive. From these studies the authors conclude that /sup 125/I-LSD labels serotonin 5-HT/sub 2/ receptor sites in cortical regions with no indication that other receptor sites are labeled. In the olfactory tubercles and hypothalamus, /sup 125/I-LSD labeling occurs predominantly or entirely at serotonic 5-HT/sub 2/ sites. In the striatum, /sup 125/I-LSD labels approximately equal proportions of serotonergic and dopaminergic sites. These data indicate that /sup 125/I-LSD labels serotonin receptors in vivo and suggests that appropriate derivatives of 2I-LSD may prove useful for tomographic imaging of serotonin 5-HT/sub 2/ receptors in the mammalian cortex.« less

Discriminating Schizophrenia and Bipolar Disorder by Fusing FMRI and DTI in A Multimodal CCA+ Joint ICA Model

PubMed Central

Sui, Jing; Pearlson, Godfrey; Adali, Tülay; Kiehl, Kent A.; Caprihan, Arvind; Liu, Jingyu; Yamamoto, Jeremy; Calhoun, Vince D.

2011-01-01

Diverse structural and functional brain alterations have been identified in both schizophrenia and bipolar disorder, but with variable replicability, significant overlap and often in limited number of subjects. In this paper, we aimed to clarify differences between bipolar disorder and schizophrenia by combining fMRI (collected during an auditory oddball task) and diffusion tensor imaging (DTI) data. We proposed a fusion method, “multimodal CCA+ joint ICA’, which increases flexibility in statistical assumptions beyond existing approaches and can achieve higher estimation accuracy. The data collected from 164 participants (62 healthy controls, 54 schizophrenia and 48 bipolar) were extracted into “features” (contrast maps for fMRI and fractional anisotropy (FA) for DTI) and analyzed in multiple facets to investigate the group differences for each pair-wised groups and each modality. Specifically, both patient groups shared significant dysfunction in dorsolateral prefrontal cortex and thalamus, as well as reduced white matter (WM) integrity in anterior thalamic radiation and uncinate fasciculus. Schizophrenia and bipolar subjects were separated by functional differences in medial frontal and visual cortex, as well as WM tracts associated with occipital and frontal lobes. Both patients and controls showed similar spatial distributions in motor and parietal regions, but exhibited significant variations in temporal lobe. Furthermore, there were different group trends for age effects on loading parameters in motor cortex and multiple WM regions, suggesting brain dysfunction and WM disruptions occurred in identified regions for both disorders. Most importantly, we can visualize an underlying function-structure network by evaluating the joint components with strong links between DTI and fMRI. Our findings suggest that although the two patient groups showed several distinct brain patterns from each other and healthy controls, they also shared common abnormalities in prefrontal thalamic WM integrity and in frontal brain mechanisms. PMID:21640835

The Effects of Histone Deacetylase Inhibition on the Levels of Cerebral Cytokines in an Animal Model of Mania Induced by Dextroamphetamine.

PubMed

Valvassori, Samira S; Resende, Wilson R; Varela, Roger B; Arent, Camila O; Gava, Fernanda F; Peterle, Bruna R; Dal-Pont, Gustavo C; Carvalho, André F; Andersen, Monica L; Quevedo, João

2018-02-01

Studies have suggested the involvement of inflammatory processes in the physiopathology of bipolar disorder. Preclinical evidences have shown that histone deacetylase inhibitors may act as mood-stabilizing agents and protect the brain in models of mania and depression. The aim of the present study was to evaluate the effects of sodium butyrate (SB) and valproate (VPA) on behavioral changes, histone deacetylase activity, and the levels of cytokines in an animal model of mania induced by dextroamphetamine (d-AMPH). Wistar rats were first given d-AMPH or saline (Sal) for a period of 14 days, and then, between the 8th and 14th days, the rats were treated with SB, VPA, or Sal. The activity of histone deacetylase and the levels of cytokines (interleukin (IL) IL-4, IL-6, and IL-10 and tumor necrosis factor-alpha (TNF-α)) were evaluated in the frontal cortex and striatum of the rats. The administration of d-AMPH increased the activity of histone deacetylase in the frontal cortex. Administration of SB or VPA decreased the levels of histone deacetylase activity in the frontal cortex and striatum of rats. SB per se increased the levels of cytokines in both of the brain structures evaluated. AMPH increased the levels of cytokines in both of the brain structures evaluated, and VPA reversed this alteration. The effects of SB on d-AMPH-induced cytokine alterations were dependent on the brain structure and the cytokine evaluated. Despite VPA and SB having a similar mechanism of action, both being histone deacetylase inhibitors, they showed different effects on the levels of cytokines. The present study reinforces the need for more research into histone deacetylase inhibitors being used as a possible target for new medications in the treatment of bipolar disorder.

Paternal alcohol exposure in mice alters brain NGF and BDNF and increases ethanol-elicited preference in male offspring.

PubMed

Ceccanti, Mauro; Coccurello, Roberto; Carito, Valentina; Ciafrè, Stefania; Ferraguti, Giampiero; Giacovazzo, Giacomo; Mancinelli, Rosanna; Tirassa, Paola; Chaldakov, George N; Pascale, Esterina; Ceccanti, Marco; Codazzo, Claudia; Fiore, Marco

2016-07-01

Ethanol (EtOH) exposure during pregnancy induces cognitive and physiological deficits in the offspring. However, the role of paternal alcohol exposure (PAE) on offspring EtOH sensitivity and neurotrophins has not received much attention. The present study examined whether PAE may disrupt nerve growth factor (NGF) and/or brain-derived neurotrophic factor (BDNF) and affect EtOH preference/rewarding properties in the male offspring. CD1 sire mice were chronically addicted for EtOH or administered with sucrose. Their male offsprings when adult were assessed for EtOH preference by a conditioned place preference paradigm. NGF and BDNF, their receptors (p75(NTR) , TrkA and TrkB), dopamine active transporter (DAT), dopamine receptors D1 and D2, pro-NGF and pro-BDNF were also evaluated in brain areas. PAE affected NGF levels in frontal cortex, striatum, olfactory lobes, hippocampus and hypothalamus. BDNF alterations in frontal cortex, striatum and olfactory lobes were found. PAE induced a higher susceptibility to the EtOH rewarding effects mostly evident at the lower concentration (0.5 g/kg) that was ineffective in non-PAE offsprings. Moreover, higher ethanol concentrations (1.5 g/kg) produced an aversive response in PAE animals and a significant preference in non-PAE offspring. PAE affected also TrkA in the hippocampus and p75(NTR) in the frontal cortex. DAT was affected in the olfactory lobes in PAE animals treated with 0.5 g/kg of ethanol while no differences were found on D1/D2 receptors and for pro-NGF or pro-BDNF. In conclusion, this study shows that: PAE affects NGF and BDNF expression in the mouse brain; PAE may induce ethanol intake preference in the male offspring. © 2015 Society for the Study of Addiction.

Differences in the neural correlates of frontal lobe tests.

PubMed

Matsuoka, Teruyuki; Kato, Yuka; Imai, Ayu; Fujimoto, Hiroshi; Shibata, Keisuke; Nakamura, Kaeko; Yamada, Kei; Narumoto, Jin

2018-01-01

The Executive Interview (EXIT25), the executive clock-drawing task (CLOX1), and the Frontal Assessment Battery (FAB) are used to assess executive function at the bedside. These tests assess distinct psychometric properties. The aim of this study was to examine differences in the neural correlates of the EXIT25, CLOX1, and FAB based on magnetic resonance imaging. Fifty-eight subjects (30 with Alzheimer's disease, 10 with mild cognitive impairment, and 18 healthy controls) participated in this study. Multiple regression analyses were performed to examine the brain regions correlated with the EXIT25, CLOX1, and FAB scores. Age, gender, and years of education were included as covariates. Statistical thresholds were set to uncorrected P-values of 0.001 at the voxel level and 0.05 at the cluster level. The EXIT25 score correlated inversely with the regional grey matter volume in the left lateral frontal lobe (Brodmann areas 6, 9, 44, and 45). The CLOX1 score correlated positively with the regional grey matter volume in the right orbitofrontal cortex (Brodmann area 11) and the left supramarginal gyrus (Brodmann area 40). The FAB score correlated positively with the regional grey matter volume in the right precentral gyrus (Brodmann area 6). The left lateral frontal lobe (Brodmann area 9) and the right lateral frontal lobe (Brodmann area 46) were identified as common brain regions that showed association with EXIT25, CLOX1, and FAB based only a voxel-level threshold. The results of this study suggest that the EXIT25, CLOX1, and FAB may be associated with the distinct neural correlates of the frontal cortex. © 2018 Japanese Psychogeriatric Society.

Magnetic Field Homogenization of the Human Prefrontal Cortex with a Set of Localized Electrical Coils

PubMed Central

Juchem, Christoph; Nixon, Terence W.; McIntyre, Scott; Rothman, Douglas L.; de Graaf, Robin A.

2011-01-01

The prefrontal cortex is a common target brain structure in psychiatry and neuroscience due to its role in working memory and cognitive control. Large differences in magnetic susceptibility between the air-filled sinuses and the tissue/bone in the frontal part of the human head cause a strong and highly localized magnetic field focus in the prefrontal cortex. As a result, image distortion and signal dropout are observed in MR imaging. A set of external, electrical coils is presented that provides localized and high amplitude shim fields in the prefrontal cortex with minimum impact on the rest of the brain when combined with regular zero-to-second order spherical harmonics shimming. The experimental realization of the new shim method strongly minimized or even eliminated signal dropout in gradient-echo images acquired at settings typically used in functional magnetic resonance at 4 Tesla. PMID:19918909

Interpreting sulci on hominin endocasts: old hypotheses and new findings

PubMed Central

Falk, Dean

2014-01-01

Paleoneurologists analyze internal casts (endocasts) of fossilized braincases, which provide information about the size, shape and, to a limited degree, sulcal patterns reproduced from impressions left by the surface of the brain. When interpreted in light of comparative data from the brains of living apes and humans, sulcal patterns reproduced on hominin endocasts provide important information for studying the evolution of the cerebral cortex and cognition in human ancestors. Here, new evidence is discussed for the evolution of sulcal patterns associated with cortical reorganization in three parts of the hominin brain: (1) the parietotemporo-occipital association cortex, (2) Broca's speech area, and (3) dorsolateral prefrontal association cortex. Of the three regions, the evidence regarding the last is the clearest. Compared to great apes, Australopithecus endocasts reproduce a clear middle frontal sulcus in the dorsolateral prefrontal cortex that is derived toward the human condition. This finding is consistent with data from comparative cytoarchitectural studies of ape and human brains as well as shape analyses of australopithecine endocasts. The comparative and direct evidence for all three regions suggests that hominin brain reorganization was underway by at least the time of Australopithecus africanus (~2.5 to 3.0 mya), despite the ape-sized brains of these hominins, and that it entailed expansion of both rostral and caudal association cortices. PMID:24822043

Comparisons of Korsakoff and Non-Korsakoff Alcoholics on Neuropsychological Tests of Prefrontal Brain Functioning

PubMed Central

Oscar-Berman, Marlene; Kirkley, Shalene M.; Gansler, David A.; Couture, Ashley

2014-01-01

Background Evidence suggests that alcoholics exhibit particular deficits in brain systems involving the prefrontal cortex, but few studies have directly compared patients with and without Korsakoff’s syndrome on measures of prefrontal integrity. Methods Neuropsychological tasks sensitive to dysfunction of frontal brain systems were administered, along with standard tests of memory, intelligence, and visuospatial abilities, to 50 healthy, abstinent, nonamnesic alcoholics, 6 patients with alcohol-induced persisting amnestic disorder (Korsakoff’s syndrome), 6 brain-damaged controls with right hemisphere lesions, and 82 healthy nonalcoholic controls. Results Korsakoff patients were impaired on tests of memory, fluency, cognitive flexibility, and perseveration. Non-Korsakoff alcoholics showed some frontal system deficits as well, but these were mild. Cognitive deficits in non-Korsakoff alcoholics were related to age, duration of abstinence (less than 5 years), duration of abuse (more than 20 years), and amount of alcohol intake. Conclusions Abnormalities of frontal system functioning are most apparent in alcoholics with Korsakoff’s syndrome. In non-Korsakoff alcoholics, factors contributing to cognitive performance are age, duration of abstinence, duration of alcoholism, and amount of alcohol consumed. PMID:15100620

Jealousy increased by induced relative left frontal cortical activity.

PubMed

Kelley, Nicholas J; Eastwick, Paul W; Harmon-Jones, Eddie; Schmeichel, Brandon J

2015-10-01

Asymmetric frontal cortical activity may be one key to the process linking social exclusion to jealous feelings. The current research examined the causal role of asymmetric frontal brain activity in modulating jealousy in response to social exclusion. Transcranial direct-current stimulation (tDCS) over the frontal cortex to manipulate asymmetric frontal cortical activity was combined with a modified version of the Cyberball paradigm designed to induce jealousy. After receiving 15 min of tDCS, participants were excluded by a desired partner and reported how jealous they felt. Among individuals who were excluded, tDCS to increase relative left frontal cortical activity caused greater levels of self-reported jealousy compared to tDCS to increase relative right frontal cortical activity or sham stimulation. Limitations concerning the specificity of this effect and implications for the role of the asymmetric prefrontal cortical activity in motivated behaviors are discussed. (c) 2015 APA, all rights reserved).

Type 1 Diabetes and Impaired Awareness of Hypoglycemia Are Associated with Reduced Brain Gray Matter Volumes.

PubMed

Bednarik, Petr; Moheet, Amir A; Grohn, Heidi; Kumar, Anjali F; Eberly, Lynn E; Seaquist, Elizabeth R; Mangia, Silvia

2017-01-01

In this study, we retrospectively analyzed the anatomical MRI data acquired from 52 subjects with type 1 diabetes (26M/26F, 36 ± 11 years old, A1C = 7.2 ± 0.9%) and 50 age, sex and BMI frequency-matched non-diabetic controls (25M/25F, 36 ± 14 years old). The T1D group was further sub-divided based on whether subjects had normal, impaired, or indeterminate awareness of hypoglycemia ( n = 31, 20, and 1, respectively). Our goals were to test whether the gray matter (GM) volumes of selected brain regions were associated with diabetes status as well as with the status of hypoglycemia awareness. T1D subjects were found to have slightly smaller volume of the whole cortex as compared to controls (-2.7%, p = 0.016), with the most affected brain region being the frontal lobe (-3.6%, p = 0.024). Similar differences of even larger magnitude were observed among the T1D subjects based on their hypoglycemia awareness status. Indeed, compared to the patients with normal awareness of hypoglycemia, patients with impaired awareness had smaller volume of the whole cortex (-7.9%, p = 0.0009), and in particular of the frontal lobe (-9.1%, p = 0.006), parietal lobe (-8.0%, p = 0.015) and temporal lobe (-8.2%, p = 0.009). Such differences were very similar to those observed between patients with impaired awareness and controls (-7.6%, p = 0.0002 in whole cortex, -9.1%, p = 0.0003 in frontal lobe, -7.8%, p = 0.002 in parietal lobe, and -6.4%, p = 0.019 in temporal lobe). On the other hand, patients with normal awareness did not present significant volume differences compared to controls. No group-differences were observed in the occipital lobe or in the anterior cingulate, posterior cingulate, hippocampus, and thalamus. We conclude that diabetes status is associated with a small but statistically significant reduction of the whole cortex volume, mainly in the frontal lobe. The most prominent structural effects occurred in patients with impaired awareness of hypoglycemia (IAH) as compared to those with normal awareness, perhaps due to the long-term exposure to recurrent episodes of hypoglycemia. Future studies aimed at quantifying relationships of structural outcomes with functional outcomes, with cognitive performance, as well as with parameters describing glucose variability and severity of hypoglycemia episodes, will be necessary to further understand the impact of T1D on the brain.

Abnormalities of functional brain networks in pathological gambling: a graph-theoretical approach

PubMed Central

Tschernegg, Melanie; Crone, Julia S.; Eigenberger, Tina; Schwartenbeck, Philipp; Fauth-Bühler, Mira; Lemènager, Tagrid; Mann, Karl; Thon, Natasha; Wurst, Friedrich M.; Kronbichler, Martin

2013-01-01

Functional neuroimaging studies of pathological gambling (PG) demonstrate alterations in frontal and subcortical regions of the mesolimbic reward system. However, most investigations were performed using tasks involving reward processing or executive functions. Little is known about brain network abnormalities during task-free resting state in PG. In the present study, graph-theoretical methods were used to investigate network properties of resting state functional magnetic resonance imaging data in PG. We compared 19 patients with PG to 19 healthy controls (HCs) using the Graph Analysis Toolbox (GAT). None of the examined global metrics differed between groups. At the nodal level, pathological gambler showed a reduced clustering coefficient in the left paracingulate cortex and the left juxtapositional lobe (supplementary motor area, SMA), reduced local efficiency in the left SMA, as well as an increased node betweenness for the left and right paracingulate cortex and the left SMA. At an uncorrected threshold level, the node betweenness in the left inferior frontal gyrus was decreased and increased in the caudate. Additionally, increased functional connectivity between fronto-striatal regions and within frontal regions has also been found for the gambling patients. These findings suggest that regions associated with the reward system demonstrate reduced segregation but enhanced integration while regions associated with executive functions demonstrate reduced integration. The present study makes evident that PG is also associated with abnormalities in the topological network structure of the brain during rest. Since alterations in PG cannot be explained by direct effects of abused substances on the brain, these findings will be of relevance for understanding functional connectivity in other addictive disorders. PMID:24098282

Reduced cortical thickness and increased surface area in antisocial personality disorder.

PubMed

Jiang, Weixiong; Li, Gang; Liu, Huasheng; Shi, Feng; Wang, Tao; Shen, Celina; Shen, Hui; Lee, Seong-Whan; Hu, Dewen; Wang, Wei; Shen, Dinggang

2016-11-19

Antisocial personality disorder (ASPD), one of whose characteristics is high impulsivity, is of great interest in the field of brain structure and function. However, little is known about possible impairments in the cortical anatomy in ASPD, in terms of cortical thickness (CTh) and surface area (SA), as well as their possible relationship with impulsivity. In this neuroimaging study, we first investigated the changes of CTh and SA in ASPD patients, in comparison to those of healthy controls, and then performed correlation analyses between these measures and the ability of impulse control. We found that ASPD patients showed thinner cortex while larger SA in several specific brain regions, i.e., bilateral superior frontal gyrus (SFG), orbitofrontal and triangularis, insula cortex, precuneus, middle frontal gyrus (MFG), middle temporal gyrus (MTG), and left bank of superior temporal sulcus (STS). In addition, we also found that the ability of impulse control was positively correlated with CTh in the SFG, MFG, orbitofrontal cortex (OFC), pars triangularis, superior temporal gyrus (STG), and insula cortex. To our knowledge, this study is the first to reveal simultaneous changes in CTh and SA in ASPD, as well as their relationship with impulsivity. These cortical structural changes may introduce uncontrolled and callous behavioral characteristic in ASPD patients, and these potential biomarkers may be very helpful in understanding the pathomechanism of ASPD. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

The role of left inferior frontal cortex during audiovisual speech perception in infants.

PubMed

Altvater-Mackensen, Nicole; Grossmann, Tobias

2016-06-01

In the first year of life, infants' speech perception attunes to their native language. While the behavioral changes associated with native language attunement are fairly well mapped, the underlying mechanisms and neural processes are still only poorly understood. Using fNIRS and eye tracking, the current study investigated 6-month-old infants' processing of audiovisual speech that contained matching or mismatching auditory and visual speech cues. Our results revealed that infants' speech-sensitive brain responses in inferior frontal brain regions were lateralized to the left hemisphere. Critically, our results further revealed that speech-sensitive left inferior frontal regions showed enhanced responses to matching when compared to mismatching audiovisual speech, and that infants with a preference to look at the speaker's mouth showed an enhanced left inferior frontal response to speech compared to infants with a preference to look at the speaker's eyes. These results suggest that left inferior frontal regions play a crucial role in associating information from different modalities during native language attunement, fostering the formation of multimodal phonological categories. Copyright © 2016 Elsevier Inc. All rights reserved.

Cannabis Abusers Show Hypofrontality and Blunted Brain Responses to a Stimulant Challenge in Females but not in Males

PubMed Central

Wiers, Corinde E; Shokri-Kojori, Ehsan; Wong, Christopher T; Abi-Dargham, Anissa; Demiral, Şükrü B; Tomasi, Dardo; Wang, Gene-Jack; Volkow, Nora D

2016-01-01

The extent to which cannabis is deleterious to the human brain is not well understood. Here, we test whether cannabis abusers (CA) have impaired frontal function and reactivity to dopaminergic signaling, which are fundamental to relapse in addiction. We measured brain glucose metabolism using PET and [18F]FDG both at baseline (placebo) and after challenge with methylphenidate (MP), a dopamine-enhancing drug, in 24 active CA (50% female) and 24 controls (HC; 50% female). Results show that (i) CA had lower baseline glucose metabolism than HC in frontal cortex including anterior cingulate, which was associated with negative emotionality. (ii) MP increased whole-brain glucose metabolism in HC but not in CA; and group by challenge effects were most profound in putamen, caudate, midbrain, thalamus, and cerebellum. In CA, MP-induced metabolic increases in putamen correlated negatively with addiction severity. (iii) There were significant gender effects, such that both the group differences at baseline in frontal metabolism and the attenuated regional brain metabolic responses to MP were observed in female CA but not in male CA. As for other drug addictions, reduced baseline frontal metabolism is likely to contribute to relapse in CA. The attenuated responses to MP in midbrain and striatum are consistent with decreased brain reactivity to dopamine stimulation and might contribute to addictive behaviors in CA. The gender differences suggest that females are more sensitive than males to the adverse effects of cannabis in brain. PMID:27156854

Therapy-induced brain reorganization patterns in aphasia.

PubMed

Abel, Stefanie; Weiller, Cornelius; Huber, Walter; Willmes, Klaus; Specht, Karsten

2015-04-01

Both hemispheres are engaged in recovery from word production deficits in aphasia. Lexical therapy has been shown to induce brain reorganization even in patients with chronic aphasia. However, the interplay of factors influencing reorganization patterns still remains unresolved. We were especially interested in the relation between lesion site, therapy-induced recovery, and beneficial reorganization patterns. Thus, we applied intensive lexical therapy, which was evaluated with functional magnetic resonance imaging, to 14 chronic patients with aphasic word retrieval deficits. In a group study, we aimed to illuminate brain reorganization of the naming network in comparison with healthy controls. Moreover, we intended to analyse the data with joint independent component analysis to relate lesion sites to therapy-induced brain reorganization, and to correlate resulting components with therapy gain. As a result, we found peri-lesional and contralateral activations basically overlapping with premorbid naming networks observed in healthy subjects. Reduced activation patterns for patients compared to controls before training comprised damaged left hemisphere language areas, right precentral and superior temporal gyrus, as well as left caudate and anterior cingulate cortex. There were decreasing activations of bilateral visuo-cognitive, articulatory, attention, and language areas due to therapy, with stronger decreases for patients in right middle temporal gyrus/superior temporal sulcus, bilateral precuneus as well as left anterior cingulate cortex and caudate. The joint independent component analysis revealed three components indexing lesion subtypes that were associated with patient-specific recovery patterns. Activation decreases (i) of an extended frontal lesion disconnecting language pathways occurred in left inferior frontal gyrus; (ii) of a small frontal lesion were found in bilateral inferior frontal gyrus; and (iii) of a large temporo-parietal lesion occurred in bilateral inferior frontal gyrus and contralateral superior temporal gyrus. All components revealed increases in prefrontal areas. One component was negatively correlated with therapy gain. Therapy was associated exclusively with activation decreases, which could mainly be attributed to higher processing efficiency within the naming network. In our joint independent component analysis, all three lesion patterns disclosed involved deactivation of left inferior frontal gyrus. Moreover, we found evidence for increased demands on control processes. As expected, we saw partly differential reorganization profiles depending on lesion patterns. There was no compensatory deactivation for the large left inferior frontal lesion, with its less advantageous outcome probably being related to its disconnection from crucial language processing pathways. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Episodic Memory in Detoxified Alcoholics: Contribution of Grey Matter Microstructure Alteration

PubMed Central

Chanraud, Sandra; Leroy, Claire; Martelli, Catherine; Kostogianni, Nikoleta; Delain, Françoise; Aubin, Henri-Jean; Reynaud, Michel; Martinot, Jean-Luc

2009-01-01

Even though uncomplicated alcoholics may likely have episodic memory deficits, discrepancies exist regarding to the integrity of brain regions that underlie this function in healthy subjects. Possible relationships between episodic memory and 1) brain microstructure assessed by magnetic resonance diffusion tensor imaging (DTI), 2) brain volumes assessed by voxel-based morphometry (VBM) were investigated in uncomplicated, detoxified alcoholics. Diffusion and morphometric analyses were performed in 24 alcohol dependent men without neurological or somatic complications and in 24 healthy men. The mean apparent coefficient of diffusion (ADC) and grey matter volumes were measured in the whole brain. Episodic memory performance was assessed using a French version of the Free and Cued Selective Reminding Test (FCSRT). Correlation analyses between verbal episodic memory, brain microstructure, and brain volumes were carried out using SPM2 software. In those with alcohol dependence, higher ADC was detected mainly in frontal, temporal and parahippocampal regions, and in the cerebellum. In alcoholics, regions with higher ADC typically also had lower grey matter volume. Low verbal episodic memory performance in alcoholism was associated with higher mean ADC in parahippocampal areas, in frontal cortex and in the left temporal cortex; no correlation was found between regional volumes and episodic memory scores. Regression analyses for the control group were not significant. These findings support the hypothesis that regional microstructural but no macrostructural alteration of the brain might be responsible, at least in part, for episodic memory deficits in alcohol dependence. PMID:19707568

Distinct roles of three frontal cortical areas in reward-guided behavior

PubMed Central

Noonan, M.P.; Mars, R.B.; Rushworth, M.F.S

2011-01-01

Functional magnetic resonance imaging (fMRI) was used to measure activity in three frontal cortical areas, lateral orbitofrontal cortex (lOFC), medial orbitofrontal cortex/ventromedial frontal cortex (mOFC/vmPFC), and anterior cingulate cortex (ACC) when expectations about type of reward, and not just reward presence or absence, could be learned. Two groups of human subjects learned twelve stimulus-response pairings. In one group (Consistent), correct performances of a given pairing were always reinforced with a specific reward outcome whereas in the other group (Inconsistent), correct performances were reinforced with randomly selected rewards. MOFC/vmPFC and lOFC were not distinguished by simple differences in relative preference for positive and negative outcomes. Instead lOFC activity reflected updating of reward-related associations specific to reward type; lOFC was active whenever informative outcomes allowed updating of reward-related associations regardless of whether the outcomes were positive or negative and the effects were greater when consistent stimulus-outcome and response-outcome mappings were present. A psycho-physiological interaction (PPI) analysis demonstrated changed coupling between lOFC and brain areas for visual object representation, such as perirhinal cortex, and reward-guided learning, such as amygdala, ventral striatum, and habenula /mediodorsal thalamus. By contrast mOFC/vmPFC activity reflected expected values of outcomes and occurrence of positive outcomes, irrespective of consistency of outcome mappings. The third frontal cortical region, ACC, reflected the use of reward type information to guide response selection. ACC activity reflected the probability of selecting the correct response, was greater when consistent outcome mappings were present, and was related to individual differences in propensity to select the correct response. PMID:21976525

Changes of oscillatory activity in pitch processing network and related tinnitus relief induced by acoustic CR neuromodulation

PubMed Central

Adamchic, Ilya; Hauptmann, Christian; Tass, Peter A.

2012-01-01

Chronic subjective tinnitus is characterized by abnormal neuronal synchronization in the central auditory system. As shown in a controlled clinical trial, acoustic coordinated reset (CR) neuromodulation causes a significant relief of tinnitus symptoms along with a significant decrease of pathological oscillatory activity in a network comprising auditory and non-auditory brain areas, which is often accompanied with a significant tinnitus pitch change. Here we studied if the tinnitus pitch change correlates with a reduction of tinnitus loudness and/or annoyance as assessed by visual analog scale (VAS) scores. Furthermore, we studied if the changes of the pattern of brain synchrony in tinnitus patients induced by 12 weeks of CR therapy depend on whether or not the patients undergo a pronounced tinnitus pitch change. Therefore, we applied standardized low-resolution brain electromagnetic tomography (sLORETA) to EEG recordings from two groups of patients with a sustained CR-induced relief of tinnitus symptoms with and without tinnitus pitch change. We found that absolute changes of VAS loudness and VAS annoyance scores significantly correlate with the modulus, i.e., the absolute value, of the tinnitus pitch change. Moreover, as opposed to patients with small or no pitch change we found a significantly stronger decrease in gamma power in patients with pronounced tinnitus pitch change in right parietal cortex (Brodmann area, BA 40), right frontal cortex (BA 9, 46), left temporal cortex (BA 22, 42), and left frontal cortex (BA 4, 6), combined with a significantly stronger increase of alpha (10–12 Hz) activity in the right and left anterior cingulate cortex (ACC; BA 32, 24). In addition, we revealed a significantly lower functional connectivity in the gamma band between the right dorsolateral prefrontal cortex (BA 46) and the right ACC (BA 32) after 12 weeks of CR therapy in patients with pronounced pitch change. Our results indicate a substantial, CR-induced reduction of tinnitus-related auditory binding in a pitch processing network. PMID:22493570

Cortical Reorganization after Hand Immobilization: The beta qEEG Spectral Coherence Evidences

PubMed Central

Fortuna, Marina; Teixeira, Silmar; Machado, Sérgio; Velasques, Bruna; Bittencourt, Juliana; Peressutti, Caroline; Budde, Henning; Cagy, Mauricio; Nardi, Antonio E.; Piedade, Roberto; Ribeiro, Pedro; Arias-Carrión, Oscar

2013-01-01

There is increasing evidence that hand immobilization is associated with various changes in the brain. Indeed, beta band coherence is strongly related to motor act and sensitive stimuli. In this study we investigate the electrophysiological and cortical changes that occur when subjects are submitted to hand immobilization. We hypothesized that beta coherence oscillations act as a mechanism underlying inter- and intra-hemispheric changes. As a methodology for our study fifteen healthy individuals between the ages of 20 and 30 years were subjected to a right index finger task before and after hand immobilization while their brain activity pattern was recorded using quantitative electroencephalography. This analysis revealed that hand immobilization caused changes in frontal, central and parietal areas of the brain. The main findings showed a lower beta-2 band in frontal regions and greater cortical activity in central and parietal areas. In summary, the coherence increased in the frontal, central and parietal cortex, due to hand immobilization and it adjusted the brains functioning, which had been disrupted by the procedure. Moreover, the brain adaptation upon hand immobilization of the subjects involved inter- and intra-hemispheric changes. PMID:24278213

Perceiving emotional expressions in others: Activation likelihood estimation meta-analyses of explicit evaluation, passive perception and incidental perception of emotions.

PubMed

Dricu, Mihai; Frühholz, Sascha

2016-12-01

We conducted a series of activation likelihood estimation (ALE) meta-analyses to determine the commonalities and distinctions between separate levels of emotion perception, namely incidental perception, passive perception, and explicit evaluation of emotional expressions. Pooling together more than 180 neuroimaging experiments using facial, vocal or body expressions, our results are threefold. First, explicitly evaluating the emotions of others recruits brain regions associated with the sensory processing of expressions, such as the inferior occipital gyrus, middle fusiform gyrus and the superior temporal gyrus, and brain regions involved in low-level and high-level mindreading, namely the posterior superior temporal sulcus, the inferior frontal cortex and dorsomedial frontal cortex. Second, we show that only the sensory regions were also consistently active during the passive perception of emotional expressions. Third, we show that the brain regions involved in mindreading were active during the explicit evaluation of both facial and vocal expressions. We discuss these results in light of the existing literature and conclude by proposing a cognitive model for perceiving and evaluating the emotions of others. Copyright © 2016 Elsevier Ltd. All rights reserved.

Rana computatrix to human language: towards a computational neuroethology of language evolution.

PubMed

Arbib, Michael A

2003-10-15

Walter's Machina speculatrix inspired the name Rana computatrix for a family of models of visuomotor coordination in the frog, which contributed to the development of computational neuroethology. We offer here an 'evolutionary' perspective on models in the same tradition for rat, monkey and human. For rat, we show how the frog-like taxon affordance model provides a basis for the spatial navigation mechanisms that involve the hippocampus and other brain regions. For monkey, we recall two models of neural mechanisms for visuomotor coordination. The first, for saccades, shows how interactions between the parietal and frontal cortex augment superior colliculus seen as the homologue of frog tectum. The second, for grasping, continues the theme of parieto-frontal interactions, linking parietal affordances to motor schemas in premotor cortex. It further emphasizes the mirror system for grasping, in which neurons are active both when the monkey executes a specific grasp and when it observes a similar grasp executed by others. The model of human-brain mechanisms is based on the mirror-system hypothesis of the evolution of the language-ready brain, which sees the human Broca's area as an evolved extension of the mirror system for grasping.

Examining frontotemporal connectivity and rTMS in healthy controls: implications for auditory hallucinations in schizophrenia.

PubMed

Gromann, Paula M; Tracy, Derek K; Giampietro, Vincent; Brammer, Michael J; Krabbendam, Lydia; Shergill, Sukhwinder S

2012-01-01

Repetitive transcranial magnetic stimulation (rTMS) has been shown to have clinically beneficial effects in altering the perception of auditory hallucinations (AH) in patients with schizophrenia. However, the mode of action is not clear. Recent neuroimaging findings indicate that rTMS has the potential to induce not only local effects but also changes in remote, functionally connected brain regions. Frontotemporal dysconnectivity has been proposed as a mechanism leading to psychotic symptoms in schizophrenia. The current study examines functional connectivity between temporal and frontal brain regions after rTMS and the implications for AH in schizophrenia. A connectivity analysis was conducted on the fMRI data of 11 healthy controls receiving rTMS, compared with 11 matched subjects receiving sham TMS, to the temporoparietal junction, before engaging in a task associated with robust frontotemporal activation. Compared to the control group, the rTMS group showed an altered frontotemporal connectivity with stronger connectivity between the right temporoparietal cortex and the dorsolateral prefrontal cortex and the angular gyrus. This finding provides preliminary evidence for the hypothesis that normalizing the functional connectivity between the temporoparietal and frontal brain regions may underlie the therapeutic effect of rTMS on AH in schizophrenia.

Aging is associated with altered inflammatory, arachidonic acid cascade and synaptic markers, influenced by epigenetic modifications, in the human frontal cortex

PubMed Central

Keleshian, Vasken L.; Modi, Hiren R.; Rapoport, Stanley I.; Rao, Jagadeesh S.

2013-01-01

Aging is a risk factor for Alzheimer’s disease (AD) and is associated with cognitive decline. However, underlying molecular mechanisms of brain aging are not clear. Recent studies suggest epigenetic influences on gene expression in AD, since DNA methylation levels influence protein and mRNA expression in postmortem AD brain. We hypothesized that some of these changes occur with normal aging. To test this hypothesis, we measured markers of the arachidonic acid (AA) cascade, neuroinflammation, pro- and anti-apoptosis factors, and gene specific epigenetic modifications in postmortem frontal cortex from nine middle-aged (41 ± 1 (SEM) years) and ten aged subjects (70 ± 3 years). The aged compared with middle-aged brain showed elevated levels of neuroinflammatory and AA cascade markers, altered pro and anti-apoptosis factors and loss of synaptophysin. Some of these changes correlated with promoter hypermethylation of BDNF, CREB, and synaptophysin and hypomethylation of BAX. These molecular alterations in aging are different from or more subtle than changes associated with AD pathology. The degree to which they are related to changes in cognition or behavior during normal aging remains to be evaluated. PMID:23336521

Structural and functional changes of the cingulate gyrus following traumatic brain injury: relation to attention and executive skills.

PubMed

Merkley, Tricia L; Larson, Michael J; Bigler, Erin D; Good, Daniel A; Perlstein, William M

2013-09-01

Impairments of attention and executive functions are common sequelae of traumatic brain injury (TBI). The anterior cingulate is implicated in conflict-related task performance, such as the Stroop, and is susceptible to TBI-related injury due to its frontal location and proximity to the rough surface of the falx cerebri. We investigated the relationship between cingulate cortex volume and performance on tasks of selective attention and cognitive flexibility (single-trial Stroop and Auditory Consonant Trigrams [ACT]). Participants consisted of 12 adults with severe TBI and 18 controls. T1-weighted volumetric MRI data were analyzed using automated cortical reconstruction, segmentation, parcellation, and volume measurement. Cortical volume reductions were prominent bilaterally in frontal, temporal, and inferior parietal regions.Specific regional reduction of the cingulate cortex was observed only for cortical volume of right caudal anterior cingulate(cACC). The TBI group performed significantly worse than control participants on the Stroop and ACT tasks. Findings suggest that atrophy of the right cACC may contribute to reduced performance on executive function tasks, such as the Stroop and ACT, although this is likely but one node of an extensive brain network involved in these cognitive processes.

Altered resting-state functional connectivity of the frontal-striatal reward system in social anxiety disorder.

PubMed

Manning, Joshua; Reynolds, Gretchen; Saygin, Zeynep M; Hofmann, Stefan G; Pollack, Mark; Gabrieli, John D E; Whitfield-Gabrieli, Susan

2015-01-01

We investigated differences in the intrinsic functional brain organization (functional connectivity) of the human reward system between healthy control participants and patients with social anxiety disorder. Functional connectivity was measured in the resting-state via functional magnetic resonance imaging (fMRI). 53 patients with social anxiety disorder and 33 healthy control participants underwent a 6-minute resting-state fMRI scan. Functional connectivity of the reward system was analyzed by calculating whole-brain temporal correlations with a bilateral nucleus accumbens seed and a ventromedial prefrontal cortex seed. Patients with social anxiety disorder, relative to the control group, had (1) decreased functional connectivity between the nucleus accumbens seed and other regions associated with reward, including ventromedial prefrontal cortex; (2) decreased functional connectivity between the ventromedial prefrontal cortex seed and lateral prefrontal regions, including the anterior and dorsolateral prefrontal cortices; and (3) increased functional connectivity between both the nucleus accumbens seed and the ventromedial prefrontal cortex seed with more posterior brain regions, including anterior cingulate cortex. Social anxiety disorder appears to be associated with widespread differences in the functional connectivity of the reward system, including markedly decreased functional connectivity between reward regions and between reward regions and lateral prefrontal cortices, and markedly increased functional connectivity between reward regions and posterior brain regions.

Mitochondrial dysfunction and lipid peroxidation in rat frontal cortex by chronic NMDA administration can be partially prevented by lithium treatment.

PubMed

Kim, Helena K; Isaacs-Trepanier, Cameron; Elmi, Nika; Rapoport, Stanley I; Andreazza, Ana C

2016-05-01

Chronic N-methyl-d-aspartate (NMDA) administration to rats may be a model to investigate excitotoxicity mediated by glutamatergic hyperactivity, and lithium has been reported to be neuroprotective. We hypothesized that glutamatergic hyperactivity in chronic NMDA injected rats would cause mitochondrial dysfunction and lipid peroxidation in the brain, and that chronic lithium treatment would ameliorate some of these NMDA-induced alterations. Rats treated with lithium for 6 weeks were injected i.p. 25 mg/kg NMDA on a daily basis for the last 21 days of lithium treatment. Brain was removed and frontal cortex was analyzed. Chronic NMDA decreased brain levels of mitochondrial complex I and III, and increased levels of the lipid oxidation products, 8-isoprostane and 4-hydroxynonenal, compared with non-NMDA injected rats. Lithium treatment prevented the NMDA-induced increments in 8-isoprostane and 4-hydroxynonenal. Our findings suggest that increased chronic activation of NMDA receptors can induce alterations in electron transport chain complexes I and III and in lipid peroxidation in brain. The NMDA-induced changes may contribute to glutamate-mediated excitotoxicity, which plays a role in brain diseases such as bipolar disorder. Lithium treatment prevented changes in 8-isoprostane and 4-hydroxynonenal, which may contribute to lithium's reported neuroprotective effect and efficacy in bipolar disorder. Copyright © 2016 Elsevier Ltd. All rights reserved.

Spontaneous alterations of regional brain activity in patients with adult generalized anxiety disorder

PubMed Central

Xia, Likun; Li, Shumei; Wang, Tianyue; Guo, Yaping; Meng, Lihong; Feng, Yunping; Cui, Yu; Wang, Fan; Ma, Jian; Jiang, Guihua

2017-01-01

Objective We aimed to examine how spontaneous brain activity might be related to the pathophysiology of generalized anxiety disorder (GAD). Patients and methods Using resting-state functional MRI, we examined spontaneous regional brain activity in 31 GAD patients (mean age, 36.87±9.16 years) and 36 healthy control participants (mean age, 39.53±8.83 years) matched for age, education, and sex from December 2014 to October 2015. We performed a two-sample t-test on the voxel-based analysis of the regional homogeneity (ReHo) maps. We used Pearson correlation analysis to compare scores from the Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale, State–Trait Anxiety Scale-Trait Scale, and mean ReHo values. Results We found abnormal spontaneous activity in multiple regions of brain in GAD patients, especially in the sensorimotor cortex and emotional regions. GAD patients showed decreased ReHo values in the right orbital middle frontal gyrus, left anterior cingulate cortex, right middle frontal gyrus, and bilateral supplementary motor areas, with increased ReHo values in the left middle temporal gyrus, left superior temporal gyrus, and right superior occipital gyrus. The ReHo value of the left middle temporal gyrus correlated positively with the Hamilton Anxiety Rating Scale scores. Conclusion These results suggest that altered local synchronization of spontaneous brain activity may be related to the pathophysiology of GAD. PMID:28790831

Gene expression changes in the course of normal brain aging are sexually dimorphic

PubMed Central

Berchtold, Nicole C.; Cribbs, David H.; Coleman, Paul D.; Rogers, Joseph; Head, Elizabeth; Kim, Ronald; Beach, Tom; Miller, Carol; Troncoso, Juan; Trojanowski, John Q.; Zielke, H. Ronald; Cotman, Carl W.

2008-01-01

Gene expression profiles were assessed in the hippocampus, entorhinal cortex, superior-frontal gyrus, and postcentral gyrus across the lifespan of 55 cognitively intact individuals aged 20–99 years. Perspectives on global gene changes that are associated with brain aging emerged, revealing two overarching concepts. First, different regions of the forebrain exhibited substantially different gene profile changes with age. For example, comparing equally powered groups, 5,029 probe sets were significantly altered with age in the superior-frontal gyrus, compared with 1,110 in the entorhinal cortex. Prominent change occurred in the sixth to seventh decades across cortical regions, suggesting that this period is a critical transition point in brain aging, particularly in males. Second, clear gender differences in brain aging were evident, suggesting that the brain undergoes sexually dimorphic changes in gene expression not only in development but also in later life. Globally across all brain regions, males showed more gene change than females. Further, Gene Ontology analysis revealed that different categories of genes were predominantly affected in males vs. females. Notably, the male brain was characterized by global decreased catabolic and anabolic capacity with aging, with down-regulated genes heavily enriched in energy production and protein synthesis/transport categories. Increased immune activation was a prominent feature of aging in both sexes, with proportionally greater activation in the female brain. These data open opportunities to explore age-dependent changes in gene expression that set the balance between neurodegeneration and compensatory mechanisms in the brain and suggest that this balance is set differently in males and females, an intriguing idea. PMID:18832152

fMRI evidence for strategic decision-making during resolution of pronoun reference.

PubMed

McMillan, Corey T; Clark, Robin; Gunawardena, Delani; Ryant, Neville; Grossman, Murray

2012-04-01

Pronouns are extraordinarily common in daily language yet little is known about the neural mechanisms that support decisions about pronoun reference. We propose a large-scale neural network for resolving pronoun reference that consists of two components. First, a core language network in peri-Sylvian cortex supports syntactic and semantic resources for interpreting pronoun meaning in sentences. Second, a frontal-parietal network that supports strategic decision-making is recruited to support probabilistic and risk-related components of resolving a pronoun's referent. In an fMRI study of healthy young adults, we observed activation of left inferior frontal and superior temporal cortex, consistent with a language network. We also observed activation of brain regions not associated with traditional language areas. By manipulating the context of the pronoun, we were able to demonstrate recruitment of dorsolateral prefrontal cortex during probabilistic evaluation of a pronoun's reference, and orbital frontal activation when a pronoun must adopt a risky referent. Together, these findings are consistent with a two-component model for resolving a pronoun's reference that includes neuroanatomic regions supporting core linguistic and decision-making mechanisms. Copyright © 2012 Elsevier Ltd. All rights reserved.

The scarcity heuristic impacts reward processing within the medial-frontal cortex.

PubMed

Williams, Chad C; Saffer, Boaz Y; McCulloch, Robert B; Krigolson, Olave E

2016-05-04

Objects that are rare are often perceived to be inherently more valuable than objects that are abundant - a bias brought about in part by the scarcity heuristic. In the present study, we sought to test whether perception of rarity impacted reward evaluation within the human medial-frontal cortex. Here, participants played a gambling game in which they flipped rare and abundant 'cards' on a computer screen to win financial rewards while electroencephalographic data were recorded. Unbeknownst to participants, reward outcome and frequency was random and equivalent for both rare and abundant cards; thus, only a perception of scarcity was true. Analysis of the electroencephalographic data indicated that the P300 component of the event-related brain potential differed in amplitude for wins and losses following the selection of rare cards, but not following the selection of abundant cards. Importantly, then, we found that the perception of card rarity impacted reward processing even though reward feedback was independent of and subsequent to card selection. Our data indicate a top-down influence of the scarcity heuristic on reward evaluation, and specifically the processing of reward magnitude, within the human medial-frontal cortex.

Translational Rodent Models of Korsakoff Syndrome Reveal the Critical Neuroanatomical Substrates of Memory Dysfunction and Recovery

PubMed Central

Hall, Joseph M.; Resende, Leticia S.

2016-01-01

Investigation of the amnesic disorder Korsakoff Syndrome (KS) has been vital in elucidating the critical brain regions involved in learning and memory. Although the thalamus and mammillary bodies are the primary sites of neuropathology in KS, functional deactivation of the hippocampus and certain cortical regions also contributes to the chronic cognitive dysfunction reported in KS. The rodent pyrithiamine-induced thiamine deficiency (PTD) model has been used to study the extent of hippocampal and cortical neuroadaptations in KS. In the PTD model, the hippocampus, frontal and retrosplenial cortical regions display loss of cholinergic innervation, decreases in behaviorally stimulated acetylcholine release and reductions in neurotrophins. While PTD treatment results in significant impairment in measures of spatial learning and memory, other cognitive processes are left intact and may be recruited to improve cognitive outcome. In addition, behavioral recovery can be stimulated in the PTD model by increasing acetylcholine levels in the medial septum, hippocampus and frontal cortex, but not in the retrosplenial cortex. These data indicate that although the hippocampus and frontal cortex are involved in the pathogenesis of KS, these regions retain neuroplasticity and may be critical targets for improving cognitive outcome in KS. PMID:22528861

Translational rodent models of Korsakoff syndrome reveal the critical neuroanatomical substrates of memory dysfunction and recovery.

PubMed

Savage, Lisa M; Hall, Joseph M; Resende, Leticia S

2012-06-01

Investigation of the amnesic disorder Korsakoff Syndrome (KS) has been vital in elucidating the critical brain regions involved in learning and memory. Although the thalamus and mammillary bodies are the primary sites of neuropathology in KS, functional deactivation of the hippocampus and certain cortical regions also contributes to the chronic cognitive dysfunction reported in KS. The rodent pyrithiamine-induced thiamine deficiency (PTD) model has been used to study the extent of hippocampal and cortical neuroadaptations in KS. In the PTD model, the hippocampus, frontal and retrosplenial cortical regions display loss of cholinergic innervation, decreases in behaviorally stimulated acetylcholine release and reductions in neurotrophins. While PTD treatment results in significant impairment in measures of spatial learning and memory, other cognitive processes are left intact and may be recruited to improve cognitive outcome. In addition, behavioral recovery can be stimulated in the PTD model by increasing acetylcholine levels in the medial septum, hippocampus and frontal cortex, but not in the retrosplenial cortex. These data indicate that although the hippocampus and frontal cortex are involved in the pathogenesis of KS, these regions retain neuroplasticity and may be critical targets for improving cognitive outcome in KS.

Common limbic and frontal-striatal disturbances in patients with obsessive compulsive disorder, panic disorder and hypochondriasis.

PubMed

van den Heuvel, O A; Mataix-Cols, D; Zwitser, G; Cath, D C; van der Werf, Y D; Groenewegen, H J; van Balkom, A J L M; Veltman, D J

2011-11-01

Direct comparisons of brain function between obsessive compulsive disorder (OCD) and other anxiety or OCD spectrum disorders are rare. This study aimed to investigate the specificity of altered frontal-striatal and limbic activations during planning in OCD, a prototypical anxiety disorder (panic disorder) and a putative OCD spectrum disorder (hypochondriasis). The Tower of London task, a 'frontal-striatal' task, was used during functional magnetic resonance imaging measurements in 50 unmedicated patients, diagnosed with OCD (n=22), panic disorder (n=14) or hypochondriasis (n=14), and in 22 healthy subjects. Blood oxygen level-dependent (BOLD) signal changes were calculated for contrasts of interest (planning versus baseline and task load effects). Moreover, correlations between BOLD responses and both task performance and state anxiety were analysed. Overall, patients showed a decreased recruitment of the precuneus, caudate nucleus, globus pallidus and thalamus, compared with healthy controls. There were no statistically significant differences in brain activation between the three patient groups. State anxiety was negatively correlated with dorsal frontal-striatal activation. Task performance was positively correlated with dorsal frontal-striatal recruitment and negatively correlated with limbic and ventral frontal-striatal recruitment. Multiple regression models showed that adequate task performance was best explained by independent contributions from dorsolateral prefrontal cortex (positive correlation) and amygdala (negative correlation), even after controlling for state anxiety. Patients with OCD, panic disorder and hypochondriasis share similar alterations in frontal-striatal brain regions during a planning task, presumably partly related to increased limbic activation.

Multispectral Brain Morphometry in Tourette Syndrome Persisting into Adulthood

ERIC Educational Resources Information Center

Draganski, Bogdan; Martino, Davide; Cavanna, Andrea E.; Hutton, Chloe; Orth, Michael; Robertson, Mary M.; Critchley, Hugo D.; Frackowiak, Richard S.

2010-01-01

Tourette syndrome is a childhood-onset neuropsychiatric disorder with a high prevalence of attention deficit hyperactivity and obsessive-compulsive disorder co-morbidities. Structural changes have been found in frontal cortex and striatum in children and adolescents. A limited number of morphometric studies in Tourette syndrome persisting into…

Remission Status and Cortical Thickness in Childhood-Onset Schizophrenia

ERIC Educational Resources Information Center

Greenstein, Deanna K.; Wolfe, Sarah; Gochman, Peter; Rapoport, Judith L.; Gogtay, Nitin

2008-01-01

Magnetic resonance imaging was used to study the relation between cortical brain thickness during admission and remission 3 months later in 56 individuals with childhood-onset schizophrenia. Findings revealed that at the time of discharge patients had thicker regional cortex in frontal, temporal and parietal regions thereby indicating that these…

Manipulation of Frontal Brain Asymmetry by Cognitive Tasks

ERIC Educational Resources Information Center

Papousek, Ilona; Schulter, Gunter

2004-01-01

The purpose of the present study was to evaluate whether verbal fluency tasks may specifically induce relatively greater left than right hemispheric activation in the dorsolateral prefrontal cortex. The effectiveness of the manipulation was evaluated by EEG, which was recorded during performance of the verbal fluency task and during two control…

Progesterone in the Field-Forward Treatment of Traumatic Brain Injury

DTIC Science & Technology

2009-11-01

After 10 min, 37 mL of acetone was added and the solution was warmed to ambient temperature. Water (25 mL) was added, and the solvent volume was...created. Concentra- tions were determined by photometric analysis. Cerebral Edema Assay. Surgery. Contusions of the medio - frontal cortex (MFC) were

Antioxidant activity of Bacopa monniera in rat frontal cortex, striatum and hippocampus.

PubMed

Bhattacharya, S K; Bhattacharya, A; Kumar, A; Ghosal, S

2000-05-01

The effect of a standardized extract of Bacopa monniera Linn. was assessed on rat brain frontal cortical, striatal and hippocampal superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities, following administration for 7, 14 or 21 days. The effects induced by this extract (bacoside A content 82% +/- 0.5%), administered in doses of 5 and 10 mg/kg, orally, were compared with the effects induced by (-) deprenyl (2 mg/kg, p. o.) administered for the same time periods. Bacopa monniera (BM) induced a dose-related increase in SOD, CAT and GPX activities, in all the brain regions investigated, after 14 and 21 days of drug administration. On the contrary, deprenyl induced an increase in SOD, CAT and GPX activities in the frontal cortex and striatum, but not in the hippocampus, after treatment for 14 or 21 days. The results suggest that BM, like deprenyl, exhibits a significant antioxidant effect after subchronic administration which, unlike the latter, extends to the hippocampus as well. The results suggest that the increase in oxidative free radical scavenging activity by BM may explain, at least in part, the cognition- facilitating action of BM, recorded in Ayurvedic texts, and demonstrated experimentally and clinically. Copyright 2000 John Wiley & Sons, Ltd.

Separating neural and vascular effects of caffeine using simultaneous EEG–FMRI: Differential effects of caffeine on cognitive and sensorimotor brain responses

PubMed Central

Diukova, Ana; Ware, Jennifer; Smith, Jessica E.; Evans, C. John; Murphy, Kevin; Rogers, Peter J.; Wise, Richard G.

2012-01-01

The effects of caffeine are mediated through its non-selective antagonistic effects on adenosine A1 and A2A adenosine receptors resulting in increased neuronal activity but also vasoconstriction in the brain. Caffeine, therefore, can modify BOLD FMRI signal responses through both its neural and its vascular effects depending on receptor distributions in different brain regions. In this study we aim to distinguish neural and vascular influences of a single dose of caffeine in measurements of task-related brain activity using simultaneous EEG–FMRI. We chose to compare low-level visual and motor (paced finger tapping) tasks with a cognitive (auditory oddball) task, with the expectation that caffeine would differentially affect brain responses in relation to these tasks. To avoid the influence of chronic caffeine intake, we examined the effect of 250 mg of oral caffeine on 14 non and infrequent caffeine consumers in a double-blind placebo-controlled cross-over study. Our results show that the task-related BOLD signal change in visual and primary motor cortex was significantly reduced by caffeine, while the amplitude and latency of visual evoked potentials over occipital cortex remained unaltered. However, during the auditory oddball task (target versus non-target stimuli) caffeine significantly increased the BOLD signal in frontal cortex. Correspondingly, there was also a significant effect of caffeine in reducing the target evoked response potential (P300) latency in the oddball task and this was associated with a positive potential over frontal cortex. Behavioural data showed that caffeine also improved performance in the oddball task with a significantly reduced number of missed responses. Our results are consistent with earlier studies demonstrating altered flow-metabolism coupling after caffeine administration in the context of our observation of a generalised caffeine-induced reduction in cerebral blood flow demonstrated by arterial spin labelling (19% reduction over grey matter). We were able to identify vascular effects and hence altered neurovascular coupling through the alteration of low-level task FMRI responses in the face of a preserved visual evoked potential. However, our data also suggest a cognitive effect of caffeine through its positive effect on the frontal BOLD signal consistent with the shortening of oddball EEG response latency. The combined use of EEG–FMRI is a promising methodology for investigating alterations in brain function in drug and disease studies where neurovascular coupling may be altered on a regional basis. PMID:22561357

Neural Correlates of Antidepressant Treatment Response in Adolescents with Major Depressive Disorder

PubMed Central

Klimes-Dougan, Bonnie; Vu, Dung Pham; Westlund Schreiner, Melinda; Mueller, Bryon A.; Eberly, Lynn E.; Camchong, Jazmin; Westervelt, Ana; Lim, Kelvin O.

2016-01-01

Abstract Objective: The neural changes underlying response to antidepressant treatment in adolescents are unknown. Identification of neural change correlates of treatment response could (1) aid in understanding mechanisms of depression and its treatment and (2) serve as target biomarkers for future research. Method: Using functional magnetic resonance imaging, we examined changes in brain activation and functional connectivity in 13 unmedicated adolescents with major depressive disorder (MDD) before and after receiving treatment with a selective serotonin reuptake inhibitor medication for 8 weeks. Specifically, we examined brain activation during a negative emotion task and resting-state functional connectivity (RSFC), focusing on the amygdala to capture networks relevant to negative emotion. We conducted whole-brain analyses to identify how symptom improvement was related to change in brain activation during a negative emotion task or amygdala RSFC. Results: After treatment, clinical improvement was associated with decreased task activation in rostral and subgenual anterior cingulate cortex and increased activation in bilateral insula, bilateral middle frontal cortices, right parahippocampus, and left cerebellum. Analysis of change in amygdala RSFC showed that treatment response was associated with increased amygdala RSFC with right frontal cortex, but decreased amygdala RSFC with right precuneus and right posterior cingulate cortex. Conclusion: The findings represent a foothold for advancing understanding of pathophysiology of MDD in adolescents by revealing the critical neural circuitry changes that underlie a positive response to a standard treatment. Although preliminary, the present study provides a research platform for future work needed to confirm these biomarkers at a larger scale before using them in future target engagement studies of novel treatments. PMID:27159204

Changes in Neural Connectivity and Memory Following a Yoga Intervention for Older Adults: A Pilot Study

PubMed Central

Eyre, Harris A.; Acevedo, Bianca; Yang, Hongyu; Siddarth, Prabha; Van Dyk, Kathleen; Ercoli, Linda; Leaver, Amber M.; Cyr, Natalie St.; Narr, Katherine; Baune, Bernhard T.; Khalsa, Dharma S.; Lavretsky, Helen

2016-01-01

Background: No study has explored the effect of yoga on cognitive decline and resting-state functional connectivity. Objectives: This study explored the relationship between performance on memory tests and resting-state functional connectivity before and after a yoga intervention versus active control for subjects with mild cognitive impairment (MCI). Methods: Participants ( ≥ 55 y) with MCI were randomized to receive a yoga intervention or active “gold-standard” control (i.e., memory enhancement training (MET)) for 12 weeks. Resting-state functional magnetic resonance imaging was used to map correlations between brain networks and memory performance changes over time. Default mode networks (DMN), language and superior parietal networks were chosen as networks of interest to analyze the association with changes in verbal and visuospatial memory performance. Results: Fourteen yoga and 11 MET participants completed the study. The yoga group demonstrated a statistically significant improvement in depression and visuospatial memory. We observed improved verbal memory performance correlated with increased connectivity between the DMN and frontal medial cortex, pregenual anterior cingulate cortex, right middle frontal cortex, posterior cingulate cortex, and left lateral occipital cortex. Improved verbal memory performance positively correlated with increased connectivity between the language processing network and the left inferior frontal gyrus. Improved visuospatial memory performance correlated inversely with connectivity between the superior parietal network and the medial parietal cortex. Conclusion:Yoga may be as effective as MET in improving functional connectivity in relation to verbal memory performance. These findings should be confirmed in larger prospective studies. PMID:27060939

Separation of trait and state in stuttering.

PubMed

Connally, Emily L; Ward, David; Pliatsikas, Christos; Finnegan, Sarah; Jenkinson, Mark; Boyles, Rowan; Watkins, Kate E

2018-04-06

Stuttering is a disorder in which the smooth flow of speech is interrupted. People who stutter show structural and functional abnormalities in the speech and motor system. It is unclear whether functional differences reflect general traits of the disorder or are specifically related to the dysfluent speech state. We used a hierarchical approach to separate state and trait effects within stuttering. We collected sparse-sampled functional MRI during two overt speech tasks (sentence reading and picture description) in 17 people who stutter and 16 fluent controls. Separate analyses identified indicators of: (1) general traits of people who stutter; (2) frequency of dysfluent speech states in subgroups of people who stutter; and (3) the differences between fluent and dysfluent states in people who stutter. We found that reduced activation of left auditory cortex, inferior frontal cortex bilaterally, and medial cerebellum were general traits that distinguished fluent speech in people who stutter from that of controls. The stuttering subgroup with higher frequency of dysfluent states during scanning (n = 9) had reduced activation in the right subcortical grey matter, left temporo-occipital cortex, the cingulate cortex, and medial parieto-occipital cortex relative to the subgroup who were more fluent (n = 8). Finally, during dysfluent states relative to fluent ones, there was greater activation of inferior frontal and premotor cortex extending into the frontal operculum, bilaterally. The above differences were seen across both tasks. Subcortical state effects differed according to the task. Overall, our data emphasise the independence of trait and state effects in stuttering. © 2018 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

The regional cerebral blood flow changes in major depressive disorder with and without psychotic features.

PubMed

Gonul, Ali Saffet; Kula, Mustafa; Bilgin, Arzu Guler; Tutus, Ahmet; Oguz, Aslan

2004-09-01

Depressive patients with psychotic features demonstrate distinct biological abnormalities in the hypothalamic-pituitary-adrenal axis (HPA), dopaminergic activity, electroencephalogram sleep profiles and measures of serotonergic function when compared to nonpsychotic depressive patients. However, very few functional neuroimaging studies were specifically designed for studying the effects of psychotic features on neuroimaging findings in depressed patients. The objective of the present study was to compare brain Single Photon Emission Tomography (SPECT) images in a group of unmedicated depressive patients with and without psychotic features. Twenty-eight patients who fully met DSM-IV criteria for major depressive disorder (MDD, 12 had psychotic features) were included in the study. They were compared with 16 control subjects matched for age, gender and education. Both psychotic and nonpsychotic depressed patients showed significantly lower regional cerebral blood flow (rCBF) values in the left and right superior frontal cortex, and left anterior cingulate cortex compared to those of controls. In comparison with depressive patients without psychotic features (DwoPF), depressive patients with psychotic features (DwPF) showed significantly lower rCBF perfusion ratios in left parietal cortex, left cerebellum but had higher rCBF perfusion ratio in the left inferior frontal cortex and caudate nucleus. The present study showed that DwPF have a different rCBF pattern compared to patients without psychotic features. Abnormalities involving inferior frontal cortex, striatum and cerebellum may play an important role in the generation of psychotic symptoms in depression.

Lateral prefrontal cortex: architectonic and functional organization

PubMed Central

Petrides, Michael

2005-01-01

A comparison of the architecture of the human prefrontal cortex with that of the macaque monkey showed a very similar architectonic organization in these two primate species. There is no doubt that the prefrontal cortical areas of the human brain have undergone considerable development, but it is equally clear that the basic architectonic organization is the same in the two species. Thus, a comparative approach to the study of the functional organization of the primate prefrontal cortex is more likely to reveal the essential aspects of the various complex control processes that are the domain of frontal function. The lateral frontal cortex appears to be functionally organized along both a rostral–caudal axis and a dorsal–ventral axis. The most caudal frontal region, the motor region on the precentral gyrus, is involved in fine motor control and direct sensorimotor mappings, whereas the caudal lateral prefrontal region is involved in higher order control processes that regulate the selection among multiple competing responses and stimuli based on conditional operations. Further rostrally, the mid-lateral prefrontal region plays an even more abstract role in cognitive control. The mid-lateral prefrontal region is itself organized along a dorsal–ventral axis of organization, with the mid-dorsolateral prefrontal cortex being involved in the monitoring of information in working memory and the mid-ventrolateral prefrontal region being involved in active judgments on information held in posterior cortical association regions that are necessary for active retrieval and encoding of information. PMID:15937012

Motor Deficits Are Produced By Removing Some Cortical Transplants Grafted Into Injured Sensorimotor Cortex of Neonatal Rats

PubMed Central

Sandor, Rick; Gonzalez, Manuel F.; Moseley, Michael; Sharp, Frank R.

1991-01-01

Fetal frontal cortex was transplanted into cavities formed in the right, motor cortex of neonatal rats. As adults, the animals were trained to press two levers in rapid succession with their left forelimb to receive food rewards. Once they had reached an optimal level of performance, the effect of removing their transplants was assessed. Surgical removal of transplants significantly impaired the performance of 2 of 4 subjects. Placing a crossstrain skin graft to induce the immunological rejection of the transplants produced a behavioral deficit in 1 of 2 subjects with complete transplant removal. Skin grafts produced no behavioral effects in four subjects that had surviving transplants. Since the motor deficit produced by transplant removal resembled those observed following the removal of normal motor cortex, we propose that these three transplants functioned within the host brain. Histology Showed that the procedures used to remove cortical grafts did not injure any host brains. Therefore, host brain damage is unlikely to account for the behavioral deterioration that followed transplant removals. PMID:1782254

Creativity and the default network: A functional connectivity analysis of the creative brain at rest☆

PubMed Central

Beaty, Roger E.; Benedek, Mathias; Wilkins, Robin W.; Jauk, Emanuel; Fink, Andreas; Silvia, Paul J.; Hodges, Donald A.; Koschutnig, Karl; Neubauer, Aljoscha C.

2014-01-01

The present research used resting-state functional magnetic resonance imaging (fMRI) to examine whether the ability to generate creative ideas corresponds to differences in the intrinsic organization of functional networks in the brain. We examined the functional connectivity between regions commonly implicated in neuroimaging studies of divergent thinking, including the inferior prefrontal cortex and the core hubs of the default network. Participants were prescreened on a battery of divergent thinking tests and assigned to high- and low-creative groups based on task performance. Seed-based functional connectivity analysis revealed greater connectivity between the left inferior frontal gyrus (IFG) and the entire default mode network in the high-creative group. The right IFG also showed greater functional connectivity with bilateral inferior parietal cortex and the left dorsolateral prefrontal cortex in the high-creative group. The results suggest that the ability to generate creative ideas is characterized by increased functional connectivity between the inferior prefrontal cortex and the default network, pointing to a greater cooperation between brain regions associated with cognitive control and low-level imaginative processes. PMID:25245940

Gene expression analysis indicates CB1 receptor upregulation in the hippocampus and neurotoxic effects in the frontal cortex 3 weeks after single-dose MDMA administration in Dark Agouti rats

PubMed Central

2013-01-01

Background 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is a widely used recreational drug known to impair cognitive functions on the long-run. Both hippocampal and frontal cortical regions have well established roles in behavior, memory formation and other cognitive tasks and damage of these regions is associated with altered behavior and cognitive functions, impairments frequently described in heavy MDMA users. The aim of this study was to examine the hippocampus, frontal cortex and dorsal raphe of Dark Agouti rats with gene expression arrays (Illumina RatRef bead arrays) looking for possible mechanisms and new candidates contributing to the effects of a single dose of MDMA (15 mg/kg) 3 weeks earlier. Results The number of differentially expressed genes in the hippocampus, frontal cortex and the dorsal raphe were 481, 155, and 15, respectively. Gene set enrichment analysis of the microarray data revealed reduced expression of 'memory’ and 'cognition’, 'dendrite development’ and 'regulation of synaptic plasticity’ gene sets in the hippocampus, parallel to the upregulation of the CB1 cannabinoid- and Epha4, Epha5, Epha6 ephrin receptors. Downregulated gene sets in the frontal cortex were related to protein synthesis, chromatin organization, transmembrane transport processes, while 'dendrite development’, 'regulation of synaptic plasticity’ and 'positive regulation of synapse assembly’ gene sets were upregulated. Changes in the dorsal raphe region were mild and in most cases not significant. Conclusion The present data raise the possibility of new synapse formation/synaptic reorganization in the frontal cortex three weeks after a single neurotoxic dose of MDMA. In contrast, a prolonged depression of new neurite formation in the hippocampus is suggested by the data, which underlines the particular vulnerability of this brain region after the drug treatment. Finally, our results also suggest the substantial contribution of CB1 receptor and endocannabinoid mediated pathways in the hippocampal impairments. Taken together the present study provides evidence for the participation of new molecular candidates in the long-term effects of MDMA. PMID:24378229

Differences in cerebral perfusion deficits in mild traumatic brain injury and depression using single-photon emission computed tomography.

PubMed

Romero, Kristoffer; Black, Sandra E; Feinstein, Anthony

2014-01-01

Numerous studies have shown decreased perfusion in the prefrontal cortex following mild traumatic brain injury (mTBI). However, similar hypoperfusion can also be observed in depression. Given the high prevalence of depressive symptoms following mTBI, it is unclear to what extent depression influences hypoperfusion in TBI. Mild TBI patients without depressive symptoms (mTBI-noD, n = 39), TBI patients with depressive symptoms (mTBI-D, n = 13), and 15 patients with major depressive disorder (MDD), but no TBI were given 99m T-ECD single-photon emission computed tomography (SPECT) scans within 2 weeks of injury. All subjects completed tests of information processing speed, complex attention, and executive functioning, and a self-report questionnaire measuring symptoms of psychological distress. Between-group comparisons of quantified SPECT perfusion were undertaken using univariate and multivariate (partial least squares) analyses. mTBI-D and mTBI-noD groups did not differ in terms of cerebral perfusion. However, patients with MDD showed hypoperfusion compared to both TBI groups in several frontal (orbitofrontal, middle frontal, and superior frontal cortex), superior temporal, and posterior cingulate regions. The mTBI-D group showed poorer performance on a measure of complex attention and working memory compared to both the mTBI-noD and MDD groups. These results suggest that depressive symptoms do not affect SPECT perfusion in the sub-acute phase following a mild TBI. Conversely, MDD is associated with hypoperfusion primarily in frontal regions.

Neuroimaging abnormalities in adults with sickle cell anemia

PubMed Central

Insel, Philip; Truran, Diana; Vichinsky, Elliot P.; Neumayr, Lynne D.; Armstrong, F.D.; Gold, Jeffrey I.; Kesler, Karen; Brewer, Joseph; Weiner, Michael W.

2014-01-01

Objective: This study was conducted to determine the relationship of frontal lobe cortical thickness and basal ganglia volumes to measures of cognition in adults with sickle cell anemia (SCA). Methods: Participants included 120 adults with SCA with no history of neurologic dysfunction and 33 healthy controls (HCs). Participants were enrolled at 12 medical center sites, and raters were blinded to diagnostic group. We hypothesized that individuals with SCA would exhibit reductions in frontal lobe cortex thickness and reduced basal ganglia and thalamus volumes compared with HCs and that these structural brain abnormalities would be associated with measures of cognitive functioning (Wechsler Adult Intelligence Scale, 3rd edition). Results: After adjusting for age, sex, education level, and intracranial volume, participants with SCA exhibited thinner frontal lobe cortex (t = −2.99, p = 0.003) and reduced basal ganglia and thalamus volumes compared with HCs (t = −3.95, p < 0.001). Reduced volume of the basal ganglia and thalamus was significantly associated with lower Performance IQ (model estimate = 3.75, p = 0.004) as well as lower Perceptual Organization (model estimate = 1.44, p = 0.007) and Working Memory scores (model estimate = 1.37, p = 0.015). Frontal lobe cortex thickness was not significantly associated with any cognitive measures. Conclusions: Our findings suggest that basal ganglia and thalamus abnormalities may represent a particularly salient contributor to cognitive dysfunction in adults with SCA. PMID:24523480

The Evolution of Human Handedness

PubMed Central

Smaers, Jeroen B; Steele, James; Case, Charleen R; Amunts, Katrin

2013-01-01

There is extensive evidence for an early vertebrate origin of lateralized motor behavior and of related asymmetries in underlying brain systems. We investigate human lateralized motor functioning in a broad comparative context of evolutionary neural reorganization. We quantify evolutionary trends in the fronto-cerebellar system (involved in motor learning) across 46 million years of divergent primate evolution by comparing rates of evolution of prefrontal cortex, frontal motor cortex, and posterior cerebellar hemispheres along individual branches of the primate tree of life. We provide a detailed evolutionary model of the neuroanatomical changes leading to modern human lateralized motor functioning, demonstrating an increased role for the fronto-cerebellar system in the apes dating to their evolutionary divergence from the monkeys (∼30 million years ago (Mya)), and a subsequent shift toward an increased role for prefrontal cortex over frontal motor cortex in the fronto-cerebellar system in the Homo-Pan ancestral lineage (∼10 Mya) and in the human ancestral lineage (∼6 Mya). We discuss these results in the context of cortico-cerebellar functions and their likely role in the evolution of human tool use and speech. PMID:23647442

Non-invasive Prefrontal/Frontal Brain Stimulation Is Not Effective in Modulating Food Reappraisal Abilities or Calorie Consumption in Obese Females

PubMed Central

Grundeis, Felicitas; Brand, Cristin; Kumar, Saurabh; Rullmann, Michael; Mehnert, Jan; Pleger, Burkhard

2017-01-01

Background/Objectives: Previous studies suggest that non-invasive transcranial direct current stimulation (tDCS) applied to the prefrontal cortex modulates food choices and calorie intake in obese humans. Participants/Methods: In the present fully randomized, placebo-controlled, within-subject and double-blinded study, we applied single sessions of anodal, cathodal, and sham tDCS to the left dorsolateral prefrontal cortex (DLPFC) and contralateral frontal operculum in 25 hungry obese women and investigated possible influences on food reappraisal abilities as well as calorie intake. We hypothesized that tDCS, (i) improves the ability to regulate the desire for visually presented foods and, (ii) reduces their consumption. Results: We could not confirm an effect of anodal or cathodal tDCS, neither on the ability to modulate the desire for visually presented foods, nor on calorie consumption. Conclusions: The present findings do not support the notion of prefrontal/frontal tDCS as a promising treatment option for obesity. PMID:28676735

Neuroprotective effects of yoga practice: age-, experience-, and frequency-dependent plasticity

PubMed Central

Villemure, Chantal; Čeko, Marta; Cotton, Valerie A.; Bushnell, M. Catherine

2015-01-01

Yoga combines postures, breathing, and meditation. Despite reported health benefits, yoga’s effects on the brain have received little study. We used magnetic resonance imaging to compare age-related gray matter (GM) decline in yogis and controls. We also examined the effect of increasing yoga experience and weekly practice on GM volume and assessed which aspects of weekly practice contributed most to brain size. Controls displayed the well documented age-related global brain GM decline while yogis did not, suggesting that yoga contributes to protect the brain against age-related decline. Years of yoga experience correlated mostly with GM volume differences in the left hemisphere (insula, frontal operculum, and orbitofrontal cortex) suggesting that yoga tunes the brain toward a parasympatically driven mode and positive states. The number of hours of weekly practice correlated with GM volume in the primary somatosensory cortex/superior parietal lobule (S1/SPL), precuneus/posterior cingulate cortex (PCC), hippocampus, and primary visual cortex (V1). Commonality analyses indicated that the combination of postures and meditation contributed the most to the size of the hippocampus, precuneus/PCC, and S1/SPL while the combination of meditation and breathing exercises contributed the most to V1 volume. Yoga’s potential neuroprotective effects may provide a neural basis for some of its beneficial effects. PMID:26029093

Voxel-based comparison of brain glucose metabolism between patients with Cushing's disease and healthy subjects.

PubMed

Liu, Shuai; Wang, Yinyan; Xu, Kaibin; Ping, Fan; Li, Fang; Wang, Renzhi; Cheng, Xin

2018-01-01

Cognitive impairment and psychiatric symptoms are common in patients with Cushing's disease (CD) owing to elevated levels of glucocorticoids. Molecular neuroimaging methods may help to detect changes in the brain of patients with CD. The aim of this study was to investigate the characteristics of brain metabolism and its association with serum cortisol level in CD. We compared brain metabolism, as measured using [ 18 F]-fluorodeoxyglucose positron emission tomography (FDG PET), between 92 patients with CD and 118 normal subjects on a voxel-wise basis. Pearson correlation was performed to evaluate the association between cerebral FDG uptake and serum cortisol level in patients with CD. We demonstrated that certain brain regions in patients with CD showed significantly increased FDG uptake, including the basal ganglia, anteromedial temporal lobe, thalamus, precentral cortex, and cerebellum. The clusters that demonstrated significantly decreased uptake were mainly located in the medial and lateral frontal cortex, superior and inferior parietal lobule, medial occipital cortex, and insular cortex. The metabolic rate of the majority of these regions was found to be significantly correlated with the serum cortisol level. Our findings may help to explain the underlying mechanisms of cognitive impairment and psychiatric symptoms in patients exposed to excessive glucocorticoids and evaluate the efficacy of treatments during follow-up.

Neonatal handling alters brain organization but does not influence recovery from perinatal cortical injury.

PubMed

Gibb, Robbin; Kolb, Bryan

2005-10-01

Handling rat pups by removing them from the nest during the preweaning period has been shown to influence brain and behavioral development. The authors hypothesized that handling rats with perinatal (Day 4) medial frontal cortex removals might attenuate behavioral deficits and reverse dendritic atrophy associated with such an injury. On the day after surgery, pups were removed from the nest for 15 min, 3 times per day until weaning. Animals were tested as adults in the Morris water task and on skilled reaching. Handled animals showed no improvement in behavioral performance. The handling procedure led to a decrease in dendritic length in parietal cortex, but spine density was unchanged. No therapeutic advantage was observed following the preweaning handling of brain-injured rats.

Cysteamine treatment ameliorates alterations in GAD67 expression and spatial memory in heterozygous reeler mice

PubMed Central

Kutiyanawalla, Ammar; Promsote, Wanwisa; Terry, Alvin; Pillai, Anilkumar

2011-01-01

Brain derived neurotrophic factor (BDNF) signaling through its receptor, TrkB is known to regulate GABAergic function and glutamic acid decarboxylase (GAD) 67 expression in neurons. Alterations in BDNF signaling have been implicated in the pathophysiology of schizophrenia and as a result, they are a potential therapeutic target. Interestingly, heterozygous reeler mice (HRM) have decreased GAD67 expression in the frontal cortex and hippocampus and they exhibit many behavioral and neurochemical abnormalities similar to schizophrenia. In the present study, we evaluated the potential of cysteamine, a neuroprotective compound to improve the deficits in GAD67 expression and cognitive function in HRM. We found that cysteamine administration (150 mg/kg/day, through drinking water) for 30 days significantly ameliorated the decreases in GAD67, mature BDNF and full-length TrkB protein levels found in frontal cortex and hippocampus of HRM. A significant attenuation of the increased levels of truncated BDNF in frontal cortex and hippocampus, as well as truncated TrkB in frontal cortex of HRM was also observed following cysteamine treatment. In behavioral studies, HRM were impaired in a Y-maze spatial recognition memory task, but not in a spontaneous alternation task or a sensorimotor, prepulse inhibition (PPI) procedure. Cysteamine improved Y-maze spatial recognition in HRM to the level of wide-type controls and it improved PPI in both wild-type and HRM. Finally, mice deficient in TrkB, showed a reduced response to cysteamine in GAD67 expression suggesting that TrkB signaling plays an important role in GAD67 regulation by cysteamine. PMID:21777509

Impairment of Novel Object Recognition Memory and Brain Insulin Signaling in Fructose- but Not Glucose-Drinking Female Rats.

PubMed

Sangüesa, Gemma; Cascales, Mar; Griñán, Christian; Sánchez, Rosa María; Roglans, Núria; Pallàs, Mercè; Laguna, Juan Carlos; Alegret, Marta

2018-01-26

Excessive sugar intake has been related to cognitive alterations, but it remains unclear whether these effects are related exclusively to increased energy intake, and the molecular mechanisms involved are not fully understood. We supplemented Sprague-Dawley female rats with 10% w/v fructose in drinking water or with isocaloric glucose solution for 7 months. Cognitive function was assessed through the Morris water maze (MWM) and the novel object recognition (NOR) tests. Plasma parameters and protein/mRNA expression in the frontal cortex and hippocampus were determined. Results showed that only fructose-supplemented rats displayed postprandial and fasting hypertriglyceridemia (1.4 and 1.9-fold, p < 0.05) and a significant reduction in the discrimination index in the NOR test, whereas the results of the MWM test showed no differences between groups. Fructose-drinking rats displayed an abnormal glucose tolerance test and impaired insulin signaling in the frontal cortex, as revealed by significant reductions in insulin receptor substrate-2 protein levels (0.77-fold, p < 0.05) and Akt phosphorylation (0.72-fold, p < 0.05), and increased insulin-degrading enzyme levels (1.86-fold, p < 0.001). Fructose supplementation reduced the expression of antioxidant enzymes and altered the amount of proteins involved in mitochondrial fusion/fission in the frontal cortex. In conclusion, cognitive deficits induced by chronic liquid fructose consumption are not exclusively related to increased caloric intake and are correlated with hypertriglyceridemia, impaired insulin signaling, increased oxidative stress and altered mitochondrial dynamics, especially in the frontal cortex.

HIV, Vascular and Aging Injuries in the Brain of Clinically Stable HIV-Infected Adults: A 1H MRS Study

PubMed Central

Cysique, Lucette A.; Moffat, Kirsten; Moore, Danielle M.; Lane, Tammy A.; Davies, Nicholas W. S.; Carr, Andrew; Brew, Bruce J.; Rae, Caroline

2013-01-01

Background Cardiovascular disease (CVD) and premature aging have been hypothesized as new risk factors for HIV associated neurocognitive disorders (HAND) in adults with virally-suppressed HIV infection. Moreover, their significance and relation to more classical HAND biomarkers remain unclear. Methods 92 HIV− infected (HIV+) adults stable on combined antiretroviral therapy (cART) and 30 age-comparable HIV-negative (HIV−) subjects underwent 1H Magnetic Resonance Spectroscopy (MRS) of the frontal white matter (targeting HIV, normal aging or CVD-related neurochemical injury), caudate nucleus (targeting HIV neurochemical injury), and posterior cingulate cortex (targeting normal/pathological aging, CVD-related neurochemical changes). All also underwent standard neuropsychological (NP) testing. CVD risk scores were calculated. HIV disease biomarkers were collected and cerebrospinal fluid (CSF) neuroinflammation biomarkers were obtained in 38 HIV+ individuals. Results Relative to HIV− individuals, HIV+ individuals presented mild MRS alterations: in the frontal white matter: lower N-Acetyl-Aspartate (NAA) (p<.04) and higher myo-inositol (mIo) (p<.04); in the caudate: lower NAA (p = .01); and in the posterior cingulate cortex: higher mIo (p<.008– also significant when Holm-Sidak corrected) and higher Choline/NAA (p<.04). Regression models showed that an HIV*age interaction was associated with lower frontal white matter NAA. CVD risk factors were associated with lower posterior cingulate cortex and caudate NAA in both groups. Past acute CVD events in the HIV+ group were associated with increased mIo in the posterior cingulate cortex. HIV duration was associated with lower caudate NAA; greater CNS cART penetration was associated with lower mIo in the posterior cingulate cortex and the degree of immune recovery on cART was associated with higher NAA in the frontal white matter. CSF neopterin was associated with higher mIo in the posterior cingulate cortex and frontal white matter. Conclusions In chronically HIV+ adults with long-term viral suppression, current CVD risk, past CVD and age are independent factors for neuronal injury and inflammation. This suggests a tripartite model of HIV, CVD and age likely driven by chronic inflammation. PMID:23620788

Brain region-selective mechanisms contribute to the progression of cerebral alterations in acute liver failure in rats.

PubMed

Cauli, Omar; López-Larrubia, Pilar; Rodrigo, Regina; Agusti, Ana; Boix, Jordi; Nieto-Charques, Laura; Cerdán, Sebastián; Felipo, Vicente

2011-02-01

Patients with acute liver failure (ALF) often die of intracranial pressure (IP) and cerebral herniation. Main contributors to increased IP are ammonia, glutamine, edema, and blood flow. The sequence of events and underlying mechanisms, as well as the temporal pattern, regional distribution, and contribution of each parameter to the progression of neurologic deterioration and IP, are unclear. We studied rats with ALF to follow the progression of changes in ammonia, glutamine, grade and type (vasogenic or cytotoxic) of edema, blood-brain barrier permeability, cerebral blood flow, and IP. We assessed whether the changes in these parameters were similar between frontal cortex and cerebellum and evaluated the presence, type, and progression of edema in 12 brain areas. ALF was induced by injection of galactosamine. The grade and type of edema was assessed by measuring the apparent diffusion coefficient by magnetic resonance imaging. Cerebral blood flow was measured by magnetic resonance and blood-brain barrier permeability by Evans blue-albumin extravasation. Increased IP arises from an early increase of blood-brain barrier permeability in certain areas (including cerebellum but not frontal cortex) followed by vasogenic edema. Ammonia and glutamine then increase progressively, leading to cytotoxic edema in many areas. Alterations in lactate and cerebral blood flow are later events that further increase IP. Different mechanisms in specific regions of the brain contribute, with different temporal patterns, to the progression of cerebral alterations and IP in ALF. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

A key role of the prefrontal cortex in the maintenance of chronic tinnitus: An fMRI study using a Stroop task.

PubMed

Araneda, Rodrigo; Renier, Laurent; Dricot, Laurence; Decat, Monique; Ebner-Karestinos, Daniela; Deggouj, Naïma; De Volder, Anne G

2018-01-01

Since we recently showed in behavioural tasks that the top-down cognitive control was specifically altered in tinnitus sufferers, here we wanted to establish the link between this impaired executive function and brain alterations in the frontal cortex in tinnitus patients. Using functional magnetic resonance imaging (fMRI), we monitored the brain activity changes in sixteen tinnitus patients (TP) and their control subjects (CS) while they were performing a spatial Stroop task, both in audition and vision. We observed that TP differed from CS in their functional recruitment of the dorsolateral prefrontal cortex (dlPFC, BA46), the cingulate gyrus and the ventromedial prefrontal cortex (vmPFC, BA10). This recruitment was higher during interference conditions in tinnitus participants than in controls, whatever the sensory modality. Furthermore, the brain activity level in the right dlPFC and vmPFC correlated with the performance in the Stroop task in TP. Due to the direct link between poor executive functions and prefrontal cortex alterations in TP, we postulate that a lack of inhibitory modulation following an impaired top-down cognitive control may maintain tinnitus by hampering habituation mechanisms. This deficit in executive functions caused by prefrontal cortex alterations would be a key-factor in the generation and persistence of tinnitus.

Reduction of Interhemispheric Functional Brain Connectivity in Early Blindness: A Resting-State fMRI Study

PubMed Central

2017-01-01

Objective The purpose of this study was to investigate the resting-state interhemispheric functional connectivity in early blindness by using voxel-mirrored homotopic connectivity (VMHC). Materials and Methods Sixteen early blind patients (EB group) and sixteen age- and gender-matched sighted control volunteers (SC group) were recruited in this study. We used VMHC to identify brain areas with significant differences in functional connectivity between different groups and used voxel-based morphometry (VBM) to calculate the individual gray matter volume (GMV). Results VMHC analysis showed a significantly lower connectivity in primary visual cortex, visual association cortex, and somatosensory association cortex in EB group compared to sighted controls. Additionally, VBM analysis revealed that GMV was reduced in the left lateral calcarine cortices in EB group compared to sighted controls, while it was increased in the left lateral middle occipital gyri. Statistical analysis showed the duration of blindness negatively correlated with VMHC in the bilateral middle frontal gyri, middle temporal gyri, and inferior temporal gyri. Conclusions Our findings help elucidate the pathophysiological mechanisms of EB. The interhemispheric functional connectivity was impaired in EB patients. Additionally, the middle frontal gyri, middle temporal gyri, and inferior temporal gyri may be potential target regions for rehabilitation. PMID:28656145

Preliminary Evidence of White Matter Abnormality in the Uncinate Fasciculus in Generalized Social Anxiety Disorder

PubMed Central

Phan, K. Luan; Orlichenko, Anton; Boyd, Erin; Angstadt, Mike; Coccaro, Emil F.; Liberzon, Israel; Arfanakis, Konstantinos

2009-01-01

Background Individuals with generalized social anxiety disorder (GSAD) exhibit exaggerated amygdala reactivity to aversive social stimuli. These findings could be explained by microstructural abnormalities in white matter (WM) tracts that connect the amygdala and prefrontal cortex, which is known to modulate the amygdala’s response to threat. The goal of this study was to investigate brain frontal WM abnormalities by using diffusion tensor imaging (DTI) in patients with social anxiety disorder. Method A Turboprop DTI sequence was used to acquire diffusion tensor images in thirty patients with GSAD and thirty matched healthy controls. Fractional anisotropy, an index of axonal organization, within WM was quantified in individual subjects and an automated voxel-based, whole-brain method was used to analyze group differences. Results Compared to healthy controls, patients had significantly lower fractional anisotropy localized to the right uncinate fasciculus WM near the orbitofrontal cortex. There were no areas of higher fractional anisotropy in patients than controls. Conclusions These findings point to an abnormality in the uncinate fasciculus, the major WM tract connecting the frontal cortex to the amygdala and other limbic temporal regions, in GSAD which could underlie the aberrant amygdala-prefrontal interactions resulting in dysfunctional social threat processing in this illness. PMID:19362707

Widespread heterogeneous neuronal loss across the cerebral cortex in Huntington's disease.

PubMed

Nana, Alissa L; Kim, Eric H; Thu, Doris C V; Oorschot, Dorothy E; Tippett, Lynette J; Hogg, Virginia M; Synek, Beth J; Roxburgh, Richard; Waldvogel, Henry J; Faull, Richard L M

2014-01-01

Huntington's disease is an autosomal dominant neurodegenerative disease characterized by neuronal degeneration in the basal ganglia and cerebral cortex, and a variable symptom profile. Although progressive striatal degeneration is known to occur and is related to symptom profile, little is known about the cellular basis of symptom heterogeneity across the entire cerebral cortex. To investigate this, we have undertaken a double blind study using unbiased stereological cell counting techniques to determine the pattern of cell loss in six representative cortical regions from the frontal, parietal, temporal, and occipital lobes in the brains of 14 Huntington's disease cases and 15 controls. The results clearly demonstrate a widespread loss of total neurons and pyramidal cells across all cortical regions studied, except for the primary visual cortex. Importantly, the results show that cell loss is remarkably variable both within and between Huntington's disease cases. The results also show that neuronal loss in the primary sensory and secondary visual cortices relate to Huntington's disease motor symptom profiles, and neuronal loss across the associational cortices in the frontal, parietal and temporal lobes is related to both Huntington's disease motor and to mood symptom profiles. This finding considerably extends a previous study (Thu et al., Brain, 2010; 133:1094-1110) which showed that neuronal loss in the primary motor cortex was related specifically to the motor symptom profiles while neuronal loss in the anterior cingulate cortex was related specifically to mood symptom profiles. The extent of cortical cell loss in the current study was generally related to the striatal neuropathological grade, but not to CAG repeat length on the HTT gene. Overall our findings show that Huntington's disease is characterized by a heterogeneous pattern of neuronal cell loss across the entire cerebrum which varies with symptom profile.

Neural correlates of the individual emotional Stroop in borderline personality disorder.

PubMed

Wingenfeld, Katja; Rullkoetter, Nina; Mensebach, Christoph; Beblo, Thomas; Mertens, Markus; Kreisel, Stefan; Toepper, Max; Driessen, Martin; Woermann, Friedrich G

2009-05-01

Emotional dysregulation is a key feature of borderline personality disorder (BPD) with altered inhibitory functions having suggested as being crucial. The anterior cingulate cortex and further prefrontal brain regions are crucial for response inhibition. The regulation of emotions is ensured via inhibitory control over the amygdala. The present study aimed to investigate neural correlates of response inhibition in BPD by using an emotional Stroop paradigm extending the task to word stimuli which were related to stressful life events. Twenty BPD patients and 20 healthy controls underwent functional magnetic resonance imaging (fMRI) while performing the individual emotional Stroop task. A block design was used with the following word type conditions: neutral words, general negative words, and individual negative words. The individual negative words were recruited from a prior interview conducted with each participant. While BPD patients had overall slower reaction times in the Stroop task compared to healthy controls, there was no increased slowing with emotional interference. Controls exhibited significant fMRI blood oxygenation level-dependent signal increases in the anterior cingulate cortex as well as in frontal cortex contrasting generally negative vs. neutral and individual negative vs. neutral conditions, respectively. BPD patients did not show equivalent signal changes. These results provide further evidence for a dysfunctional network of brain areas in BPD, including the ACC and frontal brain regions. These areas are crucial for the regulation of stress and emotions, the core problems of BPD patients.

Alterations in regional homogeneity of resting-state brain activity in fatigue of Parkinson's disease.

PubMed

Li, Junyi; Yuan, Yongsheng; Wang, Min; Zhang, Jiejin; Zhang, Li; Jiang, Siming; Ding, Jian; Zhang, Kezhong

2017-10-01

Fatigue is a common complaint in patients with Parkinson's disease (PD). However, the neural bases of fatigue in PD remain uncertain. In this cross-sectional study, our aim was to study the change of the local brain function in PD patients with fatigue. Among 49 patients with PD, 17 of them had fatigue and the remaining 32 patients without fatigue, and 25 age- and gender-matched healthy controls were enrolled. All subjects were evaluated with Fatigue Severity Scale (FSS) and had a resting-state functional magnetic resonance imaging (rs-fMRI) scan. The fMRI images were analyzed using regional homogeneity (ReHo) to study the change of the local brain function. ReHo analysis controlling for gray matter volume, age, gender, and education showed decreased ReHo in the left anterior cingulate cortex (ACC) and the right superior frontal gyrus (dorsolateral part), and increased ReHo in the left postcentral gyrus and the right inferior frontal gyrus (orbital and triangular part), compared PD-F with PD-NF; In PD patients, the regional activity in the left ACC and the right superior frontal gyrus (dorsolateral part) was negatively correlated with the FSS scores, while that in the left postcentral gyrus, the right inferior frontal gyrus (orbital and triangular part) was positively correlated with the FSS scores. This study demonstrates that brain areas including frontal, postcentral and ACC regions indicative of sensory, motor, and cognitive systems are involved in fatigue in PD patients.

Binge ethanol effects on prefrontal cortex neurons, spatial working memory and task-induced neuronal activation in male and female rats.

PubMed

West, Rebecca K; Maynard, Mark E; Leasure, J Leigh

2018-05-01

Excessive alcohol intake is associated with a multitude of health risks, especially for women. Recent studies in animal models indicate that the female brain is more negatively affected by alcohol, compared to the male brain. Among other regions, excessive alcohol consumption damages the frontal cortex, an area important for many functions and decision making of daily life. The objective of the present study was to determine whether the medial prefrontal cortex (mPFC) in female rats is selectively vulnerable to alcohol-induced damage. In humans, loss of prefrontal grey matter resulting from heavy alcohol consumption has been documented, however this volume loss is not necessarily due to a decrease in the number of neurons. We therefore quantified both number and nuclear volume of mPFC neurons following binge alcohol, as well as performance and neuronal activation during a prefrontal-dependent behavioral task. Adult male and female Long-Evans rats were assigned to binge or control groups and exposed to ethanol using a well-established 4-day model of alcohol-induced neurodegeneration. Both males and females had significantly smaller average neuronal nuclei volumes than their respective control groups immediately following alcohol binge, but neither sex showed a decrease in neuron number. Binged rats of both sexes initially showed spatial working memory deficits. Although they eventually achieved control performance, binged rats of both sexes showed increased c-Fos labeling in the mPFC during rewarded alternation, suggesting decreased neural efficiency. Overall, our results substantiate prior evidence indicating that the frontal cortex is vulnerable to alcohol, but also indicate that sex-specific vulnerability to alcohol may be brain region-dependent. Copyright © 2018 Elsevier Inc. All rights reserved.

Cognitive Reserve in Healthy Aging and Alzheimer's Disease: A Meta-Analysis of fMRI Studies.

PubMed

Colangeli, Stefano; Boccia, Maddalena; Verde, Paola; Guariglia, Paola; Bianchini, Filippo; Piccardi, Laura

2016-08-01

Cognitive reserve (CR) has been defined as the ability to optimize or maximize performance through differential recruitment of brain networks. In the present study, we aimed at providing evidence for a consistent brain network underpinning CR in healthy and pathological aging. To pursue this aim, we performed a coordinate-based meta-analysis of 17 functional magnetic resonance imaging studies on CR proxies in healthy aging, Alzheimer's disease (AD), and mild cognitive impairment (MCI). We found that different brain areas were associated with CR proxies in healthy and pathological aging. A wide network of areas, including medial and lateral frontal areas, that is, anterior cingulate cortex and dorsolateral prefrontal cortex, as well as precuneus, was associated with proxies of CR in healthy elderly patients. The CR proxies in patients with AD and amnesic-MCI were associated with activation in the anterior cingulate cortex. These results were discussed hypothesizing the existence of possible compensatory mechanisms in healthy and pathological aging. © The Author(s) 2016.

Theta dynamics reveal domain-specific control over stimulus and response conflict.

PubMed

Nigbur, Roland; Cohen, Michael X; Ridderinkhof, K Richard; Stürmer, Birgit

2012-05-01

Cognitive control allows us to adjust to environmental changes. The medial frontal cortex (MFC) is thought to detect conflicts and recruit additional resources from other brain areas including the lateral prefrontal cortices. Here we investigated how the MFC acts in concert with visual, motor, and lateral prefrontal cortices to support adaptations of goal-directed behavior. Physiologically, these interactions may occur through local and long-range synchronized oscillation dynamics, particularly in the theta range (4-8 Hz). A speeded flanker task allowed us to investigate conflict-type-specific control networks for perceptual and response conflicts. Theta power over MFC was sensitive to both perceptual and response conflict. Interareal theta phase synchrony, however, indicated a selective enhancement specific for response conflicts between MFC and left frontal cortex as well as between MFC and the presumed motor cortex contralateral to the response hand. These findings suggest that MFC theta-band activity is both generally involved in conflict processing and specifically involved in linking a neural network controlling response conflict.

Addiction Related Alteration in Resting-state Brain Connectivity

PubMed Central

Ma, Ning; Liu, Ying; Li, Nan; Wang, Chang-Xin; Zhang, Hao; Jiang, Xiao-Feng; Xu, Hu-Sheng; Fu, Xian-Ming; Hu, Xiaoping; Zhang, Da-Ren

2009-01-01

It is widely accepted that addictive drug use is related to abnormal functional organization in the user’s brain. The present study aimed to identify this type of abnormality within the brain networks implicated in addiction by resting-state functional connectivity measured with functional magnetic resonance imaging (fMRI). With fMRI data acquired during resting state from 14 chronic heroin users (12 of whom were being treated with methadone) and 13 non-addicted controls, we investigated the addiction related alteration in functional connectivity between the regions in the circuits implicated in addiction with seed-based correlation analysis. Compared with controls, chronic heroin users showed increased functional connectivity between nucleus accumbens and ventral/rostral anterior cingulate cortex (ACC), and orbital frontal cortex (OFC), between amygdala and OFC; and reduced functional connectivity between prefrontal cortex and OFC, and ACC. These observations of altered resting-state functional connectivity suggested abnormal functional organization in the addicted brain and may provide additional evidence supporting the theory of addiction that emphasizes enhanced salience value of a drug and its related cues but weakened cognitive control in the addictive state. PMID:19703568

Multiple "buy buttons" in the brain: Forecasting chocolate sales at point-of-sale based on functional brain activation using fMRI.

PubMed

Kühn, Simone; Strelow, Enrique; Gallinat, Jürgen

2016-08-01

We set out to forecast consumer behaviour in a supermarket based on functional magnetic resonance imaging (fMRI). Data was collected while participants viewed six chocolate bar communications and product pictures before and after each communication. Then self-reports liking judgement were collected. fMRI data was extracted from a priori selected brain regions: nucleus accumbens, medial orbitofrontal cortex, amygdala, hippocampus, inferior frontal gyrus, dorsomedial prefrontal cortex assumed to contribute positively and dorsolateral prefrontal cortex and insula were hypothesized to contribute negatively to sales. The resulting values were rank ordered. After our fMRI-based forecast an instore test was conducted in a supermarket on n=63.617 shoppers. Changes in sales were best forecasted by fMRI signal during communication viewing, second best by a comparison of brain signal during product viewing before and after communication and least by explicit liking judgements. The results demonstrate the feasibility of applying neuroimaging methods in a relatively small sample to correctly forecast sales changes at point-of-sale. Copyright © 2016. Published by Elsevier Inc.

A Putative Multiple-Demand System in the Macaque Brain.

PubMed

Mitchell, Daniel J; Bell, Andrew H; Buckley, Mark J; Mitchell, Anna S; Sallet, Jerome; Duncan, John

2016-08-17

In humans, cognitively demanding tasks of many types recruit common frontoparietal brain areas. Pervasive activation of this "multiple-demand" (MD) network suggests a core function in supporting goal-oriented behavior. A similar network might therefore be predicted in nonhuman primates that readily perform similar tasks after training. However, an MD network in nonhuman primates has not been described. Single-cell recordings from macaque frontal and parietal cortex show some similar properties to human MD fMRI responses (e.g., adaptive coding of task-relevant information). Invasive recordings, however, come from limited prespecified locations, so they do not delineate a macaque homolog of the MD system and their positioning could benefit from knowledge of where MD foci lie. Challenges of scanning behaving animals mean that few macaque fMRI studies specifically contrast levels of cognitive demand, so we sought to identify a macaque counterpart to the human MD system using fMRI connectivity in 35 rhesus macaques. Putative macaque MD regions, mapped from frontoparietal MD regions defined in humans, were found to be functionally connected under anesthesia. To further refine these regions, an iterative process was used to maximize their connectivity cross-validated across animals. Finally, whole-brain connectivity analyses identified voxels that were robustly connected to MD regions, revealing seven clusters across frontoparietal and insular cortex comparable to human MD regions and one unexpected cluster in the lateral fissure. The proposed macaque MD regions can be used to guide future electrophysiological investigation of MD neural coding and in task-based fMRI to test predictions of similar functional properties to human MD cortex. In humans, a frontoparietal "multiple-demand" (MD) brain network is recruited during a wide range of cognitively demanding tasks. Because this suggests a fundamental function, one might expect a similar network to exist in nonhuman primates, but this remains controversial. Here, we sought to identify a macaque counterpart to the human MD system using fMRI connectivity. Putative macaque MD regions were functionally connected under anesthesia and were further refined by iterative optimization. The result is a network including lateral frontal, dorsomedial frontal, and insular and inferior parietal regions closely similar to the human counterpart. The proposed macaque MD regions can be useful in guiding electrophysiological recordings or in task-based fMRI to test predictions of similar functional properties to human MD cortex. Copyright © 2016 Mitchell et al.

[Forensic neuropsychology at the challenge of the relationship between cognition and emotion in psychopathy].

PubMed

Alcázar-Córcoles, M A; Verdejo-García, A; Bouso-Saiz, J C

The relationship between frontal lobe damage and criminality is especially complex. The neural substrates of psychopathic behavior seem to involve structural and functional abnormalities in the frontal lobes and the limbic system. AIM. To analyze the repercussions that brain structural and functional abnormalities in psychopathic individuals may have for forensic neuropsychology. Consistent evidence indicate that response inhibition problems in psychopathic subjects are linked to structural or functional damage in the frontal cortex. Furthermore, the prefrontal cortex, along with the amygdala and the hippocampus forms the limbic system, which is an important neural substrate of emotion processing; therefore the psychopath's capacity of affective processing could also be impaired. The theoretical frameworks of the somatic marker and mirror neuron hypotheses, along with the empirical study of executive functions may contribute to explain the inability of the psychopathic subjects to feel empathy, which is one of the main inhibitors of violence and antisocial behavior. The relationship between frontal lobe dysfunction and antisocial behavior arises an important legal issue. In order to consider some type of minor liability in the case of psychopaths it is suggested to gather further research data about the relationship between frontal lobe dysfunction and the ability to inhibit antisocial behavior by making an adequate use of empathy and emotional ties.

Fluid Intelligence Allows Flexible Recruitment of the Parieto-Frontal Network in Analogical Reasoning

PubMed Central

Preusse, Franziska; Elke, van der Meer; Deshpande, Gopikrishna; Krueger, Frank; Wartenburger, Isabell

2011-01-01

Fluid intelligence is the ability to think flexibly and to understand abstract relations. People with high fluid intelligence (hi-fluIQ) perform better in analogical reasoning tasks than people with average fluid intelligence (ave-fluIQ). Although previous neuroimaging studies reported involvement of parietal and frontal brain regions in geometric analogical reasoning (which is a prototypical task for fluid intelligence), however, neuroimaging findings on geometric analogical reasoning in hi-fluIQ are sparse. Furthermore, evidence on the relation between brain activation and intelligence while solving cognitive tasks is contradictory. The present study was designed to elucidate the cerebral correlates of geometric analogical reasoning in a sample of hi-fluIQ and ave-fluIQ high school students. We employed a geometric analogical reasoning task with graded levels of task difficulty and confirmed the involvement of the parieto-frontal network in solving this task. In addition to characterizing the brain regions involved in geometric analogical reasoning in hi-fluIQ and ave-fluIQ, we found that blood oxygenation level dependency (BOLD) signal changes were greater for hi-fluIQ than for ave-fluIQ in parietal brain regions. However, ave-fluIQ showed greater BOLD signal changes in the anterior cingulate cortex and medial frontal gyrus than hi-fluIQ. Thus, we showed that a similar network of brain regions is involved in geometric analogical reasoning in both groups. Interestingly, the relation between brain activation and intelligence is not mono-directional, but rather, it is specific for each brain region. The negative brain activation–intelligence relationship in frontal brain regions in hi-fluIQ goes along with a better behavioral performance and reflects a lower demand for executive monitoring compared to ave-fluIQ individuals. In conclusion, our data indicate that flexibly modulating the extent of regional cerebral activity is characteristic for fluid intelligence. PMID:21415916

An uncommon case of random fire-setting behavior associated with Todd paralysis: a case report.

PubMed

Kanehisa, Masayuki; Morinaga, Katsuhiko; Kohno, Hisae; Maruyama, Yoshihiro; Ninomiya, Taiga; Ishitobi, Yoshinobu; Tanaka, Yoshihiro; Tsuru, Jusen; Hanada, Hiroaki; Yoshikawa, Tomoya; Akiyoshi, Jotaro

2012-08-31

The association between fire-setting behavior and psychiatric or medical disorders remains poorly understood. Although a link between fire-setting behavior and various organic brain disorders has been established, associations between fire setting and focal brain lesions have not yet been reported. Here, we describe the case of a 24-year-old first time arsonist who suffered Todd's paralysis prior to the onset of a bizarre and random fire-setting behavior. A case of a 24-year-old man with a sudden onset of a bizarre and random fire-setting behavior is reported. The man, who had been arrested on felony arson charges, complained of difficulties concentrating and of recent memory disturbances with leg weakness. A video-EEG recording demonstrated a close relationship between the focal motor impairment and a clear-cut epileptic ictal discharge involving the bilateral motor cortical areas. The SPECT result was statistically analyzed by comparing with standard SPECT images obtained from our institute (easy Z-score imaging system; eZIS). eZIS revealed hypoperfusion in cingulate cortex, basal ganglia and hyperperfusion in frontal cortex,. A neuropsychological test battery revealed lower than normal scores for executive function, attention, and memory, consistent with frontal lobe dysfunction. The fire-setting behavior and Todd's paralysis, together with an unremarkable performance on tests measuring executive function fifteen months prior, suggested a causal relationship between this organic brain lesion and the fire-setting behavior. The case describes a rare and as yet unreported association between random, impulse-driven fire-setting behavior and damage to the brain and suggests a disconnection of frontal lobe structures as a possible pathogenic mechanism.

Lifetime methamphetamine dependence is associated with cerebral microgliosis in HIV-1-infected adults.

PubMed

Soontornniyomkij, Virawudh; Umlauf, Anya; Soontornniyomkij, Benchawanna; Batki, Isabella B; Moore, David J; Masliah, Eliezer; Achim, Cristian L

2016-10-01

Methamphetamine (Meth) use is common among HIV-infected persons. It remains unclear whether Meth dependence is associated with long-lasting degenerative changes in the brain parenchyma and microvasculature of HIV-infected individuals. We examined the postmortem brains of 78 HIV-infected adults, twenty of whom were diagnosed with lifetime Meth dependence (18 past and two current at the final follow-up visit). Using logistic regression models, we analyzed associations of Meth with cerebral gliosis (immunohistochemistry for ionized calcium-binding adapter molecule-1 (Iba1) and glial fibrillary acidic protein (GFAP) in frontal, temporo-parietal, and putamen-internal capsule regions), synaptodendritic loss (confocal microscopy for synaptophysin (SYP) and microtubule-associated protein-2 (MAP2) in frontal cortex), β-amyloid plaque deposition (immunohistochemistry in frontal and temporo-parietal cortex and putamen), and arteriolosclerosis (histopathology in forebrain white matter). We found that Meth was associated with marked Iba1 gliosis in the temporo-parietal region (odds ratio, 4.42 (95 % confidence interval, 1.36, 14.39), p = 0.014, n = 62), which remained statistically significant after adjusting for HIV encephalitis, white matter lesions, and opportunistic diseases (n = 61); hepatitis C virus seropositivity (n = 54); and lifetime dependence on alcohol, opiates, and cannabis (n = 62). There was no significant association of Meth with GFAP gliosis, SYP or MAP2 loss, β-amyloid plaque deposition, or arteriolosclerosis. In conclusion, we found lifetime Meth dependence to be associated with focal cerebral microgliosis among HIV-infected adults, but not with other brain degenerative changes examined. Some of the changes in select brain regions might be reversible following extended Meth abstinence or, alternatively, might have not been induced by Meth initially.

12-h abstinence-induced functional connectivity density changes and craving in young smokers: a resting-state study.

PubMed

Zhao, Shuzhi; Li, Yangding; Li, Min; Wang, Ruonan; Bi, Yanzhi; Zhang, Yajuan; Lu, Xiaoqi; Yu, Dahua; Yang, Likun; Yuan, Kai

2018-06-20

Studying the neural correlates of craving to smoke is of great importance to improve treatment outcomes in smoking addiction. According to previous studies, the critical roles of striatum and frontal brain regions had been revealed in addiction. However, few studies focused on the hub of brain regions in the 12 h abstinence induced craving in young smokers. Thirty-one young male smokers were enrolled in the present study. A within-subject experiment design was carried out to compare functional connectivity density between 12-h smoking abstinence and smoking satiety conditions during resting state in young adult smokers by using functional connectivity density mapping (FCDM). Then, the functional connectivity density changes during smoking abstinence versus satiety were further used to examine correlations with abstinence-induced changes in subjective craving. We found young adult smokers in abstinence state (vs satiety) had higher local functional connectivity density (lFCD) and global functional connectivity density (gFCD) in brain regions including striatal subregions (i.e., bilateral caudate and putamen), frontal regions (i.e., anterior cingulate cortex (ACC) and orbital frontal cortex (OFC)) and bilateral insula. We also found higher lFCD during smoking abstinence (vs satiety) in bilateral thalamus. Additionally, the lFCD changes of the left ACC, bilateral caudate and right OFC were positively correlated with the changes in craving induced by abstinence (i.e., abstinence minus satiety) in young adult smokers. The present findings improve the understanding of the effects of acute smoking abstinence on the hubs of brain gray matter in the abstinence-induces craving and may contribute new insights into the neural mechanism of abstinence-induced craving in young smokers in smoking addiction.

Reduced Prefrontal Hemodynamic Response in Pediatric Obsessive-Compulsive Disorder as Measured by Near-Infrared Spectroscopy

ERIC Educational Resources Information Center

Ota, Toyosaku; Iida, Junzo; Sawada, Masayuki; Suehiro, Yuko; Yamamuro, Kazuhiko; Matsuura, Hiroki; Tanaka, Shohei; Kishimoto, Naoko; Negoro, Hideki; Kishimoto, Toshifumi

2013-01-01

Recent developments in near-infrared spectroscopy (NIRS) have enabled non-invasive clarification of brain functions in psychiatric disorders. Functional neuroimaging studies of patients with obsessive-compulsive disorder (OCD) have suggested that the frontal cortex and subcortical structures may play a role in the pathophysiology of the disorder.…

Dynamics of Electrocorticographic (ECoG) Activity in Human Temporal and Frontal Cortical Areas During Music Listening

DTIC Science & Technology

2012-04-14

flow or electrical activity in the primary auditory cortex and sound intensity level. Other studies (Brechmann et al., 2002; Hart et al., 2003; Tanji et...duration. Decoding of per- ceived loudness from brain signals may have important applications for the calibration of stimulation levels of cochlear implants

Early Alzheimer's disease-type pathology in the frontal cortex of wild mountain gorillas (Gorilla beringei beringei).

PubMed

Perez, Sylvia E; Sherwood, Chet C; Cranfield, Michael R; Erwin, Joseph M; Mudakikwa, Antoine; Hof, Patrick R; Mufson, Elliott J

2016-03-01

Amyloid beta (Aβ) and tau pathology have been described in the brains of captive aged great apes, but the natural progression of these age-related pathologies from wild great apes, including the gorilla, is unknown. In our previous study of Western lowland gorillas (Gorilla gorilla gorilla) who were housed in American Zoos and Aquariums-accredited facilities, we found an age-related increase in Aβ-positive plaques and vasculature, tau-positive astrocytes, oligodendrocyte coiled bodies, and neuritic clusters in the neocortex as well as hippocampus in older animals. Here, we demonstrate that aged wild mountain gorillas (Gorilla beringei beringei), who spent their entire lives in their natural habitat, also display an age-related increase in amyloid precursor protein (APP) and/or Aβ-immunoreactive blood vessels and plaques, but very limited tau pathology, in the frontal cortex. These results indicate that Aβ and tau lesions are age-related events that occur in the brain of gorillas living in captivity and in the wild. Copyright © 2016 Elsevier Inc. All rights reserved.

Selective visual attention to emotional words: Early parallel frontal and visual activations followed by interactive effects in visual cortex.

PubMed

Schindler, Sebastian; Kissler, Johanna

2016-10-01

Human brains spontaneously differentiate between various emotional and neutral stimuli, including written words whose emotional quality is symbolic. In the electroencephalogram (EEG), emotional-neutral processing differences are typically reflected in the early posterior negativity (EPN, 200-300 ms) and the late positive potential (LPP, 400-700 ms). These components are also enlarged by task-driven visual attention, supporting the assumption that emotional content naturally drives attention. Still, the spatio-temporal dynamics of interactions between emotional stimulus content and task-driven attention remain to be specified. Here, we examine this issue in visual word processing. Participants attended to negative, neutral, or positive nouns while high-density EEG was recorded. Emotional content and top-down attention both amplified the EPN component in parallel. On the LPP, by contrast, emotion and attention interacted: Explicit attention to emotional words led to a substantially larger amplitude increase than did explicit attention to neutral words. Source analysis revealed early parallel effects of emotion and attention in bilateral visual cortex and a later interaction of both in right visual cortex. Distinct effects of attention were found in inferior, middle and superior frontal, paracentral, and parietal areas, as well as in the anterior cingulate cortex (ACC). Results specify separate and shared mechanisms of emotion and attention at distinct processing stages. Hum Brain Mapp 37:3575-3587, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Enhanced peripheral visual processing in congenitally deaf humans is supported by multiple brain regions, including primary auditory cortex.

PubMed

Scott, Gregory D; Karns, Christina M; Dow, Mark W; Stevens, Courtney; Neville, Helen J

2014-01-01

Brain reorganization associated with altered sensory experience clarifies the critical role of neuroplasticity in development. An example is enhanced peripheral visual processing associated with congenital deafness, but the neural systems supporting this have not been fully characterized. A gap in our understanding of deafness-enhanced peripheral vision is the contribution of primary auditory cortex. Previous studies of auditory cortex that use anatomical normalization across participants were limited by inter-subject variability of Heschl's gyrus. In addition to reorganized auditory cortex (cross-modal plasticity), a second gap in our understanding is the contribution of altered modality-specific cortices (visual intramodal plasticity in this case), as well as supramodal and multisensory cortices, especially when target detection is required across contrasts. Here we address these gaps by comparing fMRI signal change for peripheral vs. perifoveal visual stimulation (11-15° vs. 2-7°) in congenitally deaf and hearing participants in a blocked experimental design with two analytical approaches: a Heschl's gyrus region of interest analysis and a whole brain analysis. Our results using individually-defined primary auditory cortex (Heschl's gyrus) indicate that fMRI signal change for more peripheral stimuli was greater than perifoveal in deaf but not in hearing participants. Whole-brain analyses revealed differences between deaf and hearing participants for peripheral vs. perifoveal visual processing in extrastriate visual cortex including primary auditory cortex, MT+/V5, superior-temporal auditory, and multisensory and/or supramodal regions, such as posterior parietal cortex (PPC), frontal eye fields, anterior cingulate, and supplementary eye fields. Overall, these data demonstrate the contribution of neuroplasticity in multiple systems including primary auditory cortex, supramodal, and multisensory regions, to altered visual processing in congenitally deaf adults.

Neural correlates of proactive and reactive aggression in adolescent twins.

PubMed

Yang, Yaling; Joshi, Shantanu H; Jahanshad, Neda; Thompson, Paul M; Baker, Laura A

2017-05-01

Verbal and physical aggression begin early in life and steadily decline thereafter in normal development. As a result, elevated aggressive behavior in adolescence may signal atypical development and greater vulnerability for negative mental and health outcomes. Converging evidence suggests that brain disturbances in regions involved in impulse control, emotional regulation, and sensation seeking may contribute to heightened aggression. However, little is known regarding the neural mechanisms underlying subtypes of aggression (i.e., proactive and reactive aggression) and whether they differ between males and females. Using a sample of 106 14-year-old adolescent twins, this study found that striatal enlargement was associated with both proactive and reactive aggression. We also found that volumetric alterations in several frontal regions including smaller middle frontal and larger orbitofrontal cortex were correlated with higher levels of aggression in adolescent twins. In addition, cortical thickness analysis showed that thickness alterations in many overlapping regions including middle frontal, superior frontal, and anterior cingulate cortex and temporal regions were associated with aggression in adolescent twins. Results support the involvement of fronto-limbic-striatal circuit in the etiology of aggression during adolescence. Aggr. Behav. 43:230-240, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The Exercising Brain: Changes in Functional Connectivity Induced by an Integrated Multimodal Cognitive and Whole-Body Coordination Training

PubMed Central

Demirakca, Traute; Cardinale, Vita; Dehn, Sven; Ruf, Matthias; Ende, Gabriele

2016-01-01

This study investigated the impact of “life kinetik” training on brain plasticity in terms of an increased functional connectivity during resting-state functional magnetic resonance imaging (rs-fMRI). The training is an integrated multimodal training that combines motor and cognitive aspects and challenges the brain by introducing new and unfamiliar coordinative tasks. Twenty-one subjects completed at least 11 one-hour-per-week “life kinetik” training sessions in 13 weeks as well as before and after rs-fMRI scans. Additionally, 11 control subjects with 2 rs-fMRI scans were included. The CONN toolbox was used to conduct several seed-to-voxel analyses. We searched for functional connectivity increases between brain regions expected to be involved in the exercises. Connections to brain regions representing parts of the default mode network, such as medial frontal cortex and posterior cingulate cortex, did not change. Significant connectivity alterations occurred between the visual cortex and parts of the superior parietal area (BA7). Premotor area and cingulate gyrus were also affected. We can conclude that the constant challenge of unfamiliar combinations of coordination tasks, combined with visual perception and working memory demands, seems to induce brain plasticity expressed in enhanced connectivity strength of brain regions due to coactivation. PMID:26819776

Oxytocin enhances brain function in children with autism.

PubMed

Gordon, Ilanit; Vander Wyk, Brent C; Bennett, Randi H; Cordeaux, Cara; Lucas, Molly V; Eilbott, Jeffrey A; Zagoory-Sharon, Orna; Leckman, James F; Feldman, Ruth; Pelphrey, Kevin A

2013-12-24

Following intranasal administration of oxytocin (OT), we measured, via functional MRI, changes in brain activity during judgments of socially (Eyes) and nonsocially (Vehicles) meaningful pictures in 17 children with high-functioning autism spectrum disorder (ASD). OT increased activity in the striatum, the middle frontal gyrus, the medial prefrontal cortex, the right orbitofrontal cortex, and the left superior temporal sulcus. In the striatum, nucleus accumbens, left posterior superior temporal sulcus, and left premotor cortex, OT increased activity during social judgments and decreased activity during nonsocial judgments. Changes in salivary OT concentrations from baseline to 30 min postadministration were positively associated with increased activity in the right amygdala and orbitofrontal cortex during social vs. nonsocial judgments. OT may thus selectively have an impact on salience and hedonic evaluations of socially meaningful stimuli in children with ASD, and thereby facilitate social attunement. These findings further the development of a neurophysiological systems-level understanding of mechanisms by which OT may enhance social functioning in children with ASD.

Plasma soluble CD163 is associated with postmortem brain pathology in human immunodeficiency virus infection.

PubMed

Bryant, Alex K; Moore, David J; Burdo, Tricia H; Lakritz, Jessica R; Gouaux, Ben; Soontornniyomkij, Virawudh; Achim, Cristian L; Masliah, Eliezer; Grant, Igor; Levine, Andrew J; Ellis, Ronald J

2017-04-24

Higher plasma soluble cluster of differentiation (CD)163 (sCD163), shed by monocytes and macrophages, correlates with neurocognitive impairment in HIV infection. We hypothesized that higher antemortem plasma or cerebrospinal fluid (CSF) sCD163 would be associated with greater postmortem neurodegeneration and/or microgliosis. Retrospective, postmortem observational study. We measured sCD163 levels in antemortem plasma (n = 54) and CSF (n = 32) samples from 74 HIV-seropositive participants (median 5 months before death) who donated their brains to research at autopsy. Postmortem, we quantified markers of synaptodendritic damage (microtubule-associated protein 2, synaptophysin), microgliosis [human leukocyte antigen DR (HLA-DR), ionized calcium-binding adaptor molecule 1], astrocytosis (glial fibrillary acidic protein), and impaired protein clearance (β-amyloid) in frontal cortex, hippocampus, putamen, and internal capsule. Multivariable least-squares regression was used to evaluate the association between plasma or CSF sCD163 and histological measures, correcting for multiple comparisons. Higher plasma sCD163 was associated with lower microtubule-associated protein 2 in frontal cortex [B = -0.23, 95% confidence interval (CI) -0.41 to -0.06, P = 0.04], putamen (B = 0.32, 95% CI -0.52 to -0.12, P = 0.02), and hippocampus (B = -0.23, 95% CI -0.35 to -0.10, P = 0.01), and with lower synaptophysin in hippocampus (B = -0.25, 95% CI -0.42 to -0.03, P = 0.02) but not putamen or frontal cortex (P > 0.05). Higher plasma sCD163 was associated with higher HLA-DR in putamen (B = 0.17, 95% CI 0.08 to 0.26, P = 0.008). CSF sCD163 was not associated with any histological measure (P > 0.05). Higher plasma sCD163 in life is associated with greater synaptodendritic damage and microglial activation in cortical and subcortical brain regions.

Language-associated cortical regions are proportionally larger in the female brain.

PubMed

Harasty, J; Double, K L; Halliday, G M; Kril, J J; McRitchie, D A

1997-02-01

Many studies have demonstrated significant sexual dimorphism in verbal ability. However, few studies have examined anatomical differences between the sexes that may underlie such dimorphism. To examine sex differences in the absolute and proportional volumes of the main language-associated regions of the cerebral cortex. Control neuropathological case series of consecutive autopsies from a teaching hospital. No significant age-related volume changes were identified in the sample. Two language-associated cortical regions, the superior temporal gyrus (part of the Wernicke area) and its subdivisions (planum temporale, Heschl gyrus, and anterior superior temporal gyrus) and the inferior frontal gyrus (Broca area in the dominant hemisphere), and a non-language-associated region, the frontal pole, were measured using stereological techniques in brains fixed with formaldehyde solution serially sectioned at 3-mm intervals. Volume comparisons between the sexes and between brain hemispheres were performed using 2-way analysis of variance. Studies were conducted at the University of Sydney and the Prince of Wales Medical Research Institute, Sydney, Australia. Ten males and 11 females free from neurologic or neuropathological abnormalities. The volume of the superior temporal cortex, expressed as a proportion of total cerebral volume, was significantly larger in females compared with males (17.8% increase; P = .04). This was accounted for by 1 section of the superior temporal cortex, the planum temporale, which was 29.8% larger in females (P = .04). In addition, the cortical volume fraction of the Broca area in females was 20.4% larger than in males (P = .05). In contrast, no significant differences were found in the proportional volume of the frontal pole or in regional volumes between the left and right hemispheres in either sex group. Our results suggest that females have proportionally larger Wernicke and Broca language-associated regions compared with males. These anatomical differences may correlate with superior language skills previously demonstrated in females.

Brain regions involved in the retrieval of spatial and episodic details associated with a familiar environment: an fMRI study.

PubMed

Hirshhorn, Marnie; Grady, Cheryl; Rosenbaum, R Shayna; Winocur, Gordon; Moscovitch, Morris

2012-11-01

Functional magnetic resonance imaging (fMRI) was used to compare brain activity during the retrieval of coarse- and fine-grained spatial details and episodic details associated with a familiar environment. Long-time Toronto residents compared pairs of landmarks based on their absolute geographic locations (requiring either coarse or fine discriminations) or based on previous visits to those landmarks (requiring episodic details). An ROI analysis of the hippocampus showed that all three conditions activated the hippocampus bilaterally. Fine-grained spatial judgments recruited an additional region of the right posterior hippocampus, while episodic judgments recruited an additional region of the right anterior hippocampus, and a more extensive region along the length of the left hippocampus. To examine whole-brain patterns of activity, Partial Least Squares (PLS) analysis was used to identify sets of brain regions whose activity covaried with the three conditions. All three comparison judgments recruited the default mode network including the posterior cingulate/retrosplenial cortex, middle frontal gyrus, hippocampus, and precuneus. Fine-grained spatial judgments also recruited additional regions of the precuneus, parahippocampal cortex and the supramarginal gyrus. Episodic judgments recruited the posterior cingulate and medial frontal lobes as well as the angular gyrus. These results are discussed in terms of their implications for theories of hippocampal function and spatial and episodic memory. Copyright © 2012 Elsevier Ltd. All rights reserved.

Brain intrinsic network connectivity in individuals with frequent tanning behavior.

PubMed

Ketcherside, Ariel; Filbey, Francesca M; Aubert, Pamela M; Seibyl, John P; Price, Julianne L; Adinoff, Bryon

2018-05-01

Emergent studies suggest a bidirectional relationship between brain functioning and the skin. This neurocutaneous connection may be responsible for the reward response to tanning and, thus, may contribute to excessive tanning behavior. To date, however, this association has not yet been examined. To explore whether intrinsic brain functional connectivity within the default mode network (DMN) is related to indoor tanning behavior. Resting state functional connectivity (rsFC) was obtained in twenty adults (16 females) with a history of indoor tanning. Using a seed-based [(posterior cingulate cortex (PCC)] approach, the relationship between tanning severity and FC strength was assessed. Tanning severity was measured with symptom count from the Structured Clinical Interview for Tanning Abuse and Dependence (SITAD) and tanning intensity (lifetime indoor tanning episodes/years tanning). rsFC strength between the PCC and other DMN regions (left globus pallidus, left medial frontal gyrus, left superior frontal gyrus) is positively correlated with tanning symptom count. rsFC strength between the PCC and salience network regions (right anterior cingulate cortex, left inferior parietal lobe, left inferior temporal gyrus) is correlated with tanning intensity. Greater connectivity between tanning severity and DMN and salience network connectivity suggests that heightened self-awareness of salient stimuli may be a mechanism that underlies frequent tanning behavior. These findings add to the growing evidence of brain-skin connection and reflect dysregulation in the reward processing networks in those with frequent tanning.

Effect of memantine on the levels of glial cells, neuropeptides, and peptide-degrading enzymes in rat brain regions of ibotenic acid-treated alzheimer's disease model.

PubMed

Ahmed, M M; Hoshino, H; Chikuma, T; Yamada, M; Kato, T

2004-01-01

It has been implicated that glia activation plays a critical role in the progression of Alzheimer's disease (AD). However, the precise mechanism of glia activation is not clearly understood yet. In our present studies, we confirmed our previous results where change the levels of neuropeptides and peptidases in ibotenic acid (IBO) infusion into the rat nucleus basalis magnocellularis, an animal model of AD. Furthermore, we extended our study to investigate a possible protection effect of co-administration on the changes of neuropeptides, and neuronal and glial cells in IBO-infused rat brain by memantine treatment. The levels of substance P and somatostatin were decreased in the striatum and frontal cortex 1 week after IBO infusion, and recovered to the control level by memantine treatment, indicating the involvement of neuropeptides in AD pathology. Furthermore, the immunohistochemical and enzymatic studies of GFAP and CD 11b, and peptidylarginine deiminase, markers of glia, in the striatum and frontal cortex showed the increase in IBO-treated rat brain as compared with controls, while co-administration of memantine and IBO no increase of astrocytes and microglia activation was observed. The present biochemical and immunohistochemical results suggest that glia activation might play an important role to the pathology of AD, and correlate with the changes of neuropeptide levels in AD brain that is recovered by memantine treatment.

Female adolescents with severe substance and conduct problems have substantially less brain gray matter volume.

PubMed

Dalwani, Manish S; McMahon, Mary Agnes; Mikulich-Gilbertson, Susan K; Young, Susan E; Regner, Michael F; Raymond, Kristen M; McWilliams, Shannon K; Banich, Marie T; Tanabe, Jody L; Crowley, Thomas J; Sakai, Joseph T

2015-01-01

Structural neuroimaging studies have demonstrated lower regional gray matter volume in adolescents with severe substance and conduct problems. These research studies, including ours, have generally focused on male-only or mixed-sex samples of adolescents with conduct and/or substance problems. Here we compare gray matter volume between female adolescents with severe substance and conduct problems and female healthy controls of similar ages. Female adolescents with severe substance and conduct problems will show significantly less gray matter volume in frontal regions critical to inhibition (i.e. dorsolateral prefrontal cortex and ventrolateral prefrontal cortex), conflict processing (i.e., anterior cingulate), valuation of expected outcomes (i.e., medial orbitofrontal cortex) and the dopamine reward system (i.e. striatum). We conducted whole-brain voxel-based morphometric comparison of structural MR images of 22 patients (14-18 years) with severe substance and conduct problems and 21 controls of similar age using statistical parametric mapping (SPM) and voxel-based morphometric (VBM8) toolbox. We tested group differences in regional gray matter volume with analyses of covariance, adjusting for age and IQ at p<0.05, corrected for multiple comparisons at whole-brain cluster-level threshold. Female adolescents with severe substance and conduct problems compared to controls showed significantly less gray matter volume in right dorsolateral prefrontal cortex, left ventrolateral prefrontal cortex, medial orbitofrontal cortex, anterior cingulate, bilateral somatosensory cortex, left supramarginal gyrus, and bilateral angular gyrus. Considering the entire brain, patients had 9.5% less overall gray matter volume compared to controls. Female adolescents with severe substance and conduct problems in comparison to similarly aged female healthy controls showed substantially lower gray matter volume in brain regions involved in inhibition, conflict processing, valuation of outcomes, decision-making, reward, risk-taking, and rule-breaking antisocial behavior.

Arteriolosclerosis that affects multiple brain regions is linked to hippocampal sclerosis of ageing.

PubMed

Neltner, Janna H; Abner, Erin L; Baker, Steven; Schmitt, Frederick A; Kryscio, Richard J; Jicha, Gregory A; Smith, Charles D; Hammack, Eleanor; Kukull, Walter A; Brenowitz, Willa D; Van Eldik, Linda J; Nelson, Peter T

2014-01-01

Hippocampal sclerosis of ageing is a prevalent brain disease that afflicts older persons and has been linked with cerebrovascular pathology. Arteriolosclerosis is a subtype of cerebrovascular pathology characterized by concentrically thickened arterioles. Here we report data from multiple large autopsy series (University of Kentucky Alzheimer's Disease Centre, Nun Study, and National Alzheimer's Coordinating Centre) showing a specific association between hippocampal sclerosis of ageing pathology and arteriolosclerosis. The present analyses incorporate 226 cases of autopsy-proven hippocampal sclerosis of ageing and 1792 controls. Case-control comparisons were performed including digital pathological assessments for detailed analyses of blood vessel morphology. We found no evidence of associations between hippocampal sclerosis of ageing pathology and lacunar infarcts, large infarcts, Circle of Willis atherosclerosis, or cerebral amyloid angiopathy. Individuals with hippocampal sclerosis of ageing pathology did not show increased rates of clinically documented hypertension, diabetes, or other cardiac risk factors. The correlation between arteriolosclerosis and hippocampal sclerosis of ageing pathology was strong in multiple brain regions outside of the hippocampus. For example, the presence of arteriolosclerosis in the frontal cortex (Brodmann area 9) was strongly associated with hippocampal sclerosis of ageing pathology (P < 0.001). This enables informative evaluation of anatomical regions outside of the hippocampus. To assess the morphology of brain microvasculature far more rigorously than what is possible using semi-quantitative pathological scoring, we applied digital pathological (Aperio ScanScope) methods on a subsample of frontal cortex sections from hippocampal sclerosis of ageing (n = 15) and control (n = 42) cases. Following technical studies to optimize immunostaining methods for small blood vessel visualization, our analyses focused on sections immunostained for smooth muscle actin (a marker of arterioles) and CD34 (an endothelial marker), with separate analyses on grey and white matter. A total of 43 834 smooth muscle actin-positive vascular profiles and 603 798 CD34-positive vascular profiles were evaluated. In frontal cortex of cases with hippocampal sclerosis of ageing, smooth muscle actin-immunoreactive arterioles had thicker walls (P < 0.05), larger perimeters (P < 0.03), and larger vessel areas (P < 0.03) than controls. Unlike the arterioles, CD34-immunoreactive capillaries had dimensions that were unchanged in cases with hippocampal sclerosis of ageing versus controls. Arteriolosclerosis appears specific to hippocampal sclerosis of ageing brains, because brains with Alzheimer's disease pathology did not show the same morphological alterations. We conclude that there may be a pathogenetic change in aged human brain arterioles that impacts multiple brain areas and contributes to hippocampal sclerosis of ageing.

Arteriolosclerosis that affects multiple brain regions is linked to hippocampal sclerosis of ageing

PubMed Central

Neltner, Janna H.; Abner, Erin L.; Baker, Steven; Schmitt, Frederick A.; Kryscio, Richard J.; Jicha, Gregory A.; Smith, Charles D.; Hammack, Eleanor; Kukull, Walter A.; Brenowitz, Willa D.; Van Eldik, Linda J.

2014-01-01

Hippocampal sclerosis of ageing is a prevalent brain disease that afflicts older persons and has been linked with cerebrovascular pathology. Arteriolosclerosis is a subtype of cerebrovascular pathology characterized by concentrically thickened arterioles. Here we report data from multiple large autopsy series (University of Kentucky Alzheimer’s Disease Centre, Nun Study, and National Alzheimer’s Coordinating Centre) showing a specific association between hippocampal sclerosis of ageing pathology and arteriolosclerosis. The present analyses incorporate 226 cases of autopsy-proven hippocampal sclerosis of ageing and 1792 controls. Case–control comparisons were performed including digital pathological assessments for detailed analyses of blood vessel morphology. We found no evidence of associations between hippocampal sclerosis of ageing pathology and lacunar infarcts, large infarcts, Circle of Willis atherosclerosis, or cerebral amyloid angiopathy. Individuals with hippocampal sclerosis of ageing pathology did not show increased rates of clinically documented hypertension, diabetes, or other cardiac risk factors. The correlation between arteriolosclerosis and hippocampal sclerosis of ageing pathology was strong in multiple brain regions outside of the hippocampus. For example, the presence of arteriolosclerosis in the frontal cortex (Brodmann area 9) was strongly associated with hippocampal sclerosis of ageing pathology (P < 0.001). This enables informative evaluation of anatomical regions outside of the hippocampus. To assess the morphology of brain microvasculature far more rigorously than what is possible using semi-quantitative pathological scoring, we applied digital pathological (Aperio ScanScope) methods on a subsample of frontal cortex sections from hippocampal sclerosis of ageing (n = 15) and control (n = 42) cases. Following technical studies to optimize immunostaining methods for small blood vessel visualization, our analyses focused on sections immunostained for smooth muscle actin (a marker of arterioles) and CD34 (an endothelial marker), with separate analyses on grey and white matter. A total of 43 834 smooth muscle actin-positive vascular profiles and 603 798 CD34-positive vascular profiles were evaluated. In frontal cortex of cases with hippocampal sclerosis of ageing, smooth muscle actin-immunoreactive arterioles had thicker walls (P < 0.05), larger perimeters (P < 0.03), and larger vessel areas (P < 0.03) than controls. Unlike the arterioles, CD34-immunoreactive capillaries had dimensions that were unchanged in cases with hippocampal sclerosis of ageing versus controls. Arteriolosclerosis appears specific to hippocampal sclerosis of ageing brains, because brains with Alzheimer’s disease pathology did not show the same morphological alterations. We conclude that there may be a pathogenetic change in aged human brain arterioles that impacts multiple brain areas and contributes to hippocampal sclerosis of ageing. PMID:24271328

Brain Cortical Thickness Differences in Adolescent Females with Substance Use Disorders.

PubMed

Boulos, Peter K; Dalwani, Manish S; Tanabe, Jody; Mikulich-Gilbertson, Susan K; Banich, Marie T; Crowley, Thomas J; Sakai, Joseph T

2016-01-01

We recruited right-handed female patients, 14-19 years of age, from a university-based treatment program for youths with substance use disorders and community controls similar for age, race and zip code of residence. We obtained 43 T1-weighted structural brain images (22 patients and 21 controls) to examine group differences in cortical thickness across the entire brain as well as six a priori regions-of-interest: 1) medial orbitofrontal cortex; 2) rostral anterior cingulate cortex; and 3) middle frontal cortex, in each hemisphere. Age and IQ were entered as nuisance factors for all analyses. A priori region-of-interest analyses yielded no significant differences. However, whole-brain group comparisons revealed that the left pregenual rostral anterior cingulate cortex extending into the left medial orbitofrontal region (355.84 mm2 in size), a subset of two of our a priori regions-of-interest, was significantly thinner in patients compared to controls (vertex-level threshold p = 0.005 and cluster-level family wise error corrected threshold p = 0.05). The whole-brain group differences did not survive after adjusting for depression or externalizing scores. Whole-brain within-patient analyses demonstrated a positive association between cortical thickness in the left precuneus and behavioral disinhibition scores (458.23 mm2 in size). Adolescent females with substance use disorders have significant differences in brain cortical thickness in regions engaged by the default mode network and that have been associated with problems of emotional dysregulation, inhibition, and behavioral control in past studies.

The neural correlates of visuo-spatial working memory in children with autism spectrum disorder: effects of cognitive load

PubMed Central

2014-01-01

Background Research on the neural bases of cognitive deficits in autism spectrum disorder (ASD) has shown that working memory (WM) difficulties are associated with abnormalities in the prefrontal cortex. However, cognitive load impacts these findings, and no studies have examined the relation between WM load and neural underpinnings in children with ASD. Thus, the current study determined the effects of cognitive load on WM, using a visuo-spatial WM capacity task in children with and without ASD with functional magnetic resonance imaging (fMRI). Methods We used fMRI and a 1-back colour matching task (CMT) task with four levels of difficulty to compare the cortical activation patterns associated with WM in children (7–13 years old) with high functioning autism (N = 19) and matched controls (N = 17) across cognitive load. Results Performance on CMT was comparable between groups, with the exception of one difficulty level. Using linear trend analyses, the control group showed increasing activation as a function of difficulty level in frontal and parietal lobes, particularly between the highest difficulty levels, and decreasing activation as a function of difficulty level in the posterior cingulate and medial frontal gyri. In contrast, children with ASD showed increasing activation only in posterior brain regions and decreasing activation in the posterior cingulate and medial frontal gyri, as a function of difficulty level. Significant differences were found in the precuneus, dorsolateral prefrontal cortex and medial premotor cortex, where control children showed greater positive linear relations between cortical activity and task difficulty level, particularly at the highest difficulty levels, but children with ASD did not show these trends. Conclusions Children with ASD showed differences in activation in the frontal and parietal lobes—both critical substrates for visuo-spatial WM. Our data suggest that children with ASD rely mainly on posterior brain regions associated with visual and lower level processing, whereas controls showed activity in frontal lobes related to the classic WM network. Findings will help guide future work by localizing areas of vulnerability to developmental disturbances. PMID:25057329

The Impact of Serotonin Transporter (5-HTTLPR) Genotype on the Development of Resting-State Functional Connectivity in Children and Adolescents: A Preliminary Report

PubMed Central

Wiggins, Jillian Lee; Bedoyan, Jirair K.; Peltier, Scott J.; Ashinoff, Samantha; Carrasco, Melisa; Weng, Shih-Jen; Welsh, Robert C.; Martin, Donna M.; Monk, Christopher S.

2011-01-01

A fundamental component of brain development is the formation of large-scale networks across the cortex. One such network, the default network, undergoes a protracted development, displaying weak connectivity in childhood that strengthens in adolescence and becomes most robust in adulthood. Little is known about the genetic contributions to default network connectivity in adulthood or during development. Alterations in connectivity between posterior and frontal portions of the default network have been associated with several psychological disorders, including anxiety, autism spectrum disorders, schizophrenia, depression, and attention-deficit/hyperactivity disorder. These disorders have also been linked to variants of the serotonin transporter linked polymorphic region (5-HTTLPR). The LA allele of 5-HTTLPR results in higher serotonin transporter expression than the S allele or the rarer LG allele. 5-HTTLPR may influence default network connectivity, as the superior medial frontal region has been shown to be sensitive to changes in serotonin. Also, serotonin as a growth factor early in development may alter large-scale networks such as the default network. The present study examined the influence of 5-HTTLPR variants on connectivity between the posterior and frontal structures and its development in a cross-sectional study of 39 healthy children and adolescents. We found that children and adolescents homozygous for the S allele (S/S, n = 10) showed weaker connectivity in the superior medial frontal cortex compared to those homozygous for the LA allele (LA/LA, n = 13) or heterozygotes (S/LA, S/LG, n = 16). Moreover, there was an age-by-genotype interaction, such that those with LA/LA genotype had the steepest age-related increase in connectivity between the posterior hub and superior medial frontal cortex, followed by heterozygotes. In contrast, individuals with the S/S genotype had the least age-related increase in connectivity strength. This preliminary report expands our understanding of the genetic influences on the development of large-scale brain connectivity and lays down the foundation for future research and replication of the results with a larger sample. PMID:22032950

The neural correlates of visuo-spatial working memory in children with autism spectrum disorder: effects of cognitive load.

PubMed

Vogan, Vanessa M; Morgan, Benjamin R; Lee, Wayne; Powell, Tamara L; Smith, Mary Lou; Taylor, Margot J

2014-01-01

Research on the neural bases of cognitive deficits in autism spectrum disorder (ASD) has shown that working memory (WM) difficulties are associated with abnormalities in the prefrontal cortex. However, cognitive load impacts these findings, and no studies have examined the relation between WM load and neural underpinnings in children with ASD. Thus, the current study determined the effects of cognitive load on WM, using a visuo-spatial WM capacity task in children with and without ASD with functional magnetic resonance imaging (fMRI). We used fMRI and a 1-back colour matching task (CMT) task with four levels of difficulty to compare the cortical activation patterns associated with WM in children (7-13 years old) with high functioning autism (N = 19) and matched controls (N = 17) across cognitive load. Performance on CMT was comparable between groups, with the exception of one difficulty level. Using linear trend analyses, the control group showed increasing activation as a function of difficulty level in frontal and parietal lobes, particularly between the highest difficulty levels, and decreasing activation as a function of difficulty level in the posterior cingulate and medial frontal gyri. In contrast, children with ASD showed increasing activation only in posterior brain regions and decreasing activation in the posterior cingulate and medial frontal gyri, as a function of difficulty level. Significant differences were found in the precuneus, dorsolateral prefrontal cortex and medial premotor cortex, where control children showed greater positive linear relations between cortical activity and task difficulty level, particularly at the highest difficulty levels, but children with ASD did not show these trends. Children with ASD showed differences in activation in the frontal and parietal lobes-both critical substrates for visuo-spatial WM. Our data suggest that children with ASD rely mainly on posterior brain regions associated with visual and lower level processing, whereas controls showed activity in frontal lobes related to the classic WM network. Findings will help guide future work by localizing areas of vulnerability to developmental disturbances.

LORETA analysis of three-dimensional distribution of δ band activity in schizophrenia: relation to negative symptoms.

PubMed

Itoh, Toru; Sumiyoshi, Tomiki; Higuchi, Yuko; Suzuki, Michio; Kawasaki, Yasuhiro

2011-08-01

We sought to determine if altered electroencephalography (EEG) activities, such as delta band activity, in specific brain regions are associated with psychotic symptoms. Data were obtained from 17 neuroleptic-naive patients with schizophrenia and age- and sex-matched 17 healthy control subjects. Low Resolution Brain Electromagnetic Tomography (LORETA) was used to generate current source density images of delta, theta, alpha, and beta activities. Localization of the difference in EEG activity between the two groups was assessed by voxel-by-voxel non-paired t-test of the LORETA images. Spearman's correlation coefficient was obtained to relate LORETA values of EEG current density in brain regions showing a significant between-group difference and psychopathology scores. Delta band activity, represented by LORETA current density, was greater for patients in the following areas; the left inferior temporal gyrus, right middle frontal gyrus, right superior frontal gyrus, right inferior frontal gyrus, and right parahippocampal gyrus. LORETA values for delta band activity in the above five brain regions were negatively correlated with negative, but not positive symptoms. The results of this study suggest the role for electrophysiological changes in some of the brain regions, e.g. prefrontal cortex, in the manifestation of negative symptoms. Copyright © 2011 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Modulation of electric brain responses evoked by pitch deviants through transcranial direct current stimulation.

PubMed

Royal, Isabelle; Zendel, Benjamin Rich; Desjardins, Marie-Ève; Robitaille, Nicolas; Peretz, Isabelle

2018-01-31

Congenital amusia is a neurodevelopmental disorder, characterized by a difficulty detecting pitch deviation that is related to abnormal electrical brain responses. Abnormalities found along the right fronto-temporal pathway between the inferior frontal gyrus (IFG) and the auditory cortex (AC) are the likely neural mechanism responsible for amusia. To investigate the causal role of these regions during the detection of pitch deviants, we applied cathodal (inhibitory) transcranial direct current stimulation (tDCS) over right frontal and right temporal regions during separate testing sessions. We recorded participants' electrical brain activity (EEG) before and after tDCS stimulation while they performed a pitch change detection task. Relative to a sham condition, there was a decrease in P3 amplitude after cathodal stimulation over both frontal and temporal regions compared to pre-stimulation baseline. This decrease was associated with small pitch deviations (6.25 cents), but not large pitch deviations (200 cents). Overall, this demonstrates that using tDCS to disrupt regions around the IFG and AC can induce temporary changes in evoked brain activity when processing pitch deviants. These electrophysiological changes are similar to those observed in amusia and provide causal support for the connection between P3 and fronto-temporal brain regions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Localization of Asymmetric Brain Function in Emotion and Depression

PubMed Central

Herrington, John D.; Heller, Wendy; Mohanty, Aprajita; Engels, Anna S.; Banich, Marie T.; Webb, Andrew G.; Miller, Gregory A.

2011-01-01

Although numerous EEG studies have shown that depression is associated with abnormal functional asymmetries in frontal cortex, fMRI and PET studies have largely failed to identify specific brain areas showing this effect. The present study tested the hypothesis that emotion processes are related to asymmetric patterns of fMRI activity, particularly within dorsolateral prefrontal cortex (DLPFC). Eleven depressed and 18 control participants identified the color in which pleasant, neutral, and unpleasant words were printed. Both groups showed a leftward lateralization for pleasant words in DLPFC. In a neighboring DLPFC area, the depression group showed more right-lateralized activation than controls, replicating EEG findings. These data confirm that emotional stimulus processing and trait depression are associated with asymmetric brain functions in distinct subregions of the DLPFC that may go undetected unless appropriate analytic procedures are used. PMID:20070577

Localization of asymmetric brain function in emotion and depression.

PubMed

Herrington, John D; Heller, Wendy; Mohanty, Aprajita; Engels, Anna S; Banich, Marie T; Webb, Andrew G; Miller, Gregory A

2010-05-01

Although numerous EEG studies have shown that depression is associated with abnormal functional asymmetries in frontal cortex, fMRI and PET studies have largely failed to identify specific brain areas showing this effect. The present study tested the hypothesis that emotion processes are related to asymmetric patterns of fMRI activity, particularly within dorsolateral prefrontal cortex (DLPFC). Eleven depressed and 18 control participants identified the color in which pleasant, neutral, and unpleasant words were printed. Both groups showed a leftward lateralization for pleasant words in DLPFC. In a neighboring DLPFC area, the depression group showed more right-lateralized activation than controls, replicating EEG findings. These data confirm that emotional stimulus processing and trait depression are associated with asymmetric brain functions in distinct subregions of the DLPFC that may go undetected unless appropriate analytic procedures are used.

Yawning and Stretching Predict Brain Temperature Changes in Rats: Support for the Thermoregulatory Hypothesis

PubMed Central

Shoup-Knox, Melanie L.; Gallup, Andrew C.; Gallup, Gordon G.; McNay, Ewan C.

2010-01-01

Recent research suggests that yawning is an adaptive behavior that functions to promote brain thermoregulation among homeotherms. To explore the relationship between brain temperature and yawning we implanted thermocoupled probes in the frontal cortex of rats to measure brain temperature before, during and after yawning. Temperature recordings indicate that yawns and stretches occurred during increases in brain temperature, with brain temperatures being restored to baseline following the execution of each of these behaviors. The circulatory changes that accompany yawning and stretching may explain some of the thermal similarities surrounding these events. These results suggest that yawning and stretching may serve to maintain brain thermal homeostasis. PMID:21031034

Influence of dorsolateral prefrontal cortex and ventral striatum on risk avoidance in addiction: a mediation analysis.

PubMed

Yamamoto, Dorothy J; Woo, Choong-Wan; Wager, Tor D; Regner, Michael F; Tanabe, Jody

2015-04-01

Alterations in frontal and striatal function are hypothesized to underlie risky decision making in drug users, but how these regions interact to affect behavior is incompletely understood. We used mediation analysis to investigate how prefrontal cortex and ventral striatum together influence risk avoidance in abstinent drug users. Thirty-seven abstinent substance-dependent individuals (SDI) and 43 controls underwent fMRI while performing a decision-making task involving risk and reward. Analyses of a priori regions-of-interest tested whether activity in dorsolateral prefrontal cortex (DLPFC) and ventral striatum (VST) explained group differences in risk avoidance. Whole-brain analysis was conducted to identify brain regions influencing the negative VST-risk avoidance relationship. Right DLPFC (RDLPFC) positively mediated the group-risk avoidance relationship (p < 0.05); RDLPFC activity was higher in SDI and predicted higher risk avoidance across groups, controlling for SDI vs. Conversely, VST activity negatively influenced risk avoidance (p < 0.05); it was higher in SDI, and predicted lower risk avoidance. Whole-brain analysis revealed that, across group, RDLPFC and left temporal-parietal junction positively (p ≤ 0.001) while right thalamus and left middle frontal gyrus negatively (p < 0.005) mediated the VST activity-risk avoidance relationship. RDLPFC activity mediated less risky decision making while VST mediated more risky decision making across drug users and controls. These results suggest a dual pathway underlying decision making, which, if imbalanced, may adversely influence choices involving risk. Modeling contributions of multiple brain systems to behavior through mediation analysis could lead to a better understanding of mechanisms of behavior and suggest neuromodulatory treatments for addiction. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Differences in Aβ brain networks in Alzheimer's disease and healthy controls.

PubMed

Duan, Huoqiang; Jiang, Jiehui; Xu, Jun; Zhou, Hucheng; Huang, Zhemin; Yu, Zhihua; Yan, Zhuangzhi

2017-01-15

The prevailing β-amyloid (Aβ)-cascade hypothesis is the most classical Alzheimer's disease (AD) pathogenesis. In this hypothesis, excessive Aβ plaque deposition in human brain is considered to be the cause of AD. Carbon 11-labeled Pittsburgh compound B Positron emission tomography (11C-PiB PET) is the latest technology to detect Aβ plaques in vivo. Thus, it is possible to investigate the difference of Aβ brain networks between AD patients and Health Controls (HC) by analyzing 11C-PiB PET images. In this study, a graph-theoretical method was employed to investigate the topological properties of Aβ networks in 18 Chinese AD patients and 16 HC subjects from Huashan Hospital, Shanghai. The results showed that both groups demonstrated small-world property, and this property was more obvious in AD group. Additionally, the clustering coefficients and path lengths were significantly lower in AD group. The global efficiency was larger in AD than in HC. A direct comparison between with and without regression found that sex, age and weight had no significant effect on the Aβ network. Moreover, three altered regions in AD group were identified, including left cuneus (CUN.L), right caudate nucleus (CAU.R) and left superior frontal gyrus (SFGdor. L). A voxel-wise correlation analysis showed that in AD patients, the regions of strengthened connection with CUN.L were mainly located in frontal cortex and parietal cortex, the regions of strengthen connection with CAU.R were mainly located in temporal cortex. Finally, a machine learning based analysis demonstrated that the three regions could be better biomarkers than the whole brain for AD classification. Copyright © 2016 Elsevier B.V. All rights reserved.

Altered Brain Network in Amyotrophic Lateral Sclerosis: A Resting Graph Theory-Based Network Study at Voxel-Wise Level.

PubMed

Zhou, Chaoyang; Hu, Xiaofei; Hu, Jun; Liang, Minglong; Yin, Xuntao; Chen, Lin; Zhang, Jiuquan; Wang, Jian

2016-01-01

Amyotrophic lateral sclerosis (ALS) is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex-matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC), a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe, and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC's z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS.

Influence of dorsolateral prefrontal cortex and ventral striatum on risk avoidance in addiction: a mediation analysis*

PubMed Central

Yamamoto, Dorothy J.; Woo, Choong-Wan; Wager, Tor D.; Regner, Michael F.; Tanabe, Jody

2015-01-01

Background Alterations in frontal and striatal function are hypothesized to underlie risky decision-making in drug users, but how these regions interact to affect behavior is incompletely understood. We used mediation analysis to investigate how prefrontal cortex and ventral striatum together influence risk avoidance in abstinent drug users. Method Thirty-seven abstinent substance-dependent individuals (SDI) and 43 controls underwent fMRI while performing a decision-making task involving risk and reward. Analyses of a priori regions-of-interest tested whether activity in dorsolateral prefrontal cortex (DLPFC) and ventral striatum (VST) explained group differences in risk avoidance. Whole-brain analysis was conducted to identify brain regions influencing the negative VST-risk avoidance relationship. Results Right DLPFC (RDLPFC) positively mediated the group-risk avoidance relationship (p < 0.05); RDLPFC activity was higher in SDI and predicted higher risk avoidance across groups, controlling for SDI vs. controls. Conversely, VST activity negatively influenced risk avoidance (p < 0.05); it was higher in SDI, and predicted lower risk avoidance. Whole-brain analysis revealed that, across group, RDLPFC and left temporal-parietal junction positively (p ≤ 0.001) while right thalamus and left middle frontal gyrus negatively (p < 0.005) mediated the VST activity-risk avoidance relationship. Conclusion RDLPFC activity mediated less risky decision-making while VST mediated more risky decision-making across drug users and controls. These results suggest a dual pathway underlying decision-making, which, if imbalanced, may adversely influence choices involving risk. Modeling contributions of multiple brain systems to behavior through mediation analysis could lead to a better understanding of mechanisms of behavior and suggest neuromodulatory treatments for addiction. PMID:25736619

Strategic Resource Allocation in the Human Brain Supports Cognitive Coordination of Object and Spatial Working Memory

PubMed Central

Jackson, Margaret C; Morgan, Helen M; Shapiro, Kimron L; Mohr, Harald; Linden, David EJ

2011-01-01

The ability to integrate different types of information (e.g., object identity and spatial orientation) and maintain or manipulate them concurrently in working memory (WM) facilitates the flow of ongoing tasks and is essential for normal human cognition. Research shows that object and spatial information is maintained and manipulated in WM via separate pathways in the brain (object/ventral versus spatial/dorsal). How does the human brain coordinate the activity of different specialized systems to conjoin different types of information? Here we used functional magnetic resonance imaging to investigate conjunction- versus single-task manipulation of object (compute average color blend) and spatial (compute intermediate angle) information in WM. Object WM was associated with ventral (inferior frontal gyrus, occipital cortex), and spatial WM with dorsal (parietal cortex, superior frontal, and temporal sulci) regions. Conjoined object/spatial WM resulted in intermediate activity in these specialized areas, but greater activity in different prefrontal and parietal areas. Unique to our study, we found lower temporo-occipital activity and greater deactivation in temporal and medial prefrontal cortices for conjunction- versus single-tasks. Using structural equation modeling, we derived a conjunction-task connectivity model that comprises a frontoparietal network with a bidirectional DLPFC-VLPFC connection, and a direct parietal-extrastriate pathway. We suggest that these activation/deactivation patterns reflect efficient resource allocation throughout the brain and propose a new extended version of the biased competition model of WM. Hum Brain Mapp, 2011. © 2010 Wiley-Liss, Inc. PMID:20715083

Neuroprotective effect of ginger in the brain of streptozotocin-induced diabetic rats.

PubMed

El-Akabawy, Gehan; El-Kholy, Wael

2014-05-01

Diabetes mellitus results in neuronal damage caused by increased intracellular glucose leading to oxidative stress. Recent evidence revealed the potential of ginger for reducing diabetes-induced oxidative stress markers. The aim of this study is to investigate, for the first time, whether the antioxidant properties of ginger has beneficial effects on the structural brain damage associated with diabetes. We investigated the observable neurodegenerative changes in the frontal cortex, dentate gyrus, and cerebellum after 4, 6, and 8 weeks of streptozotocin (STZ)-induced diabetes in rats and the effect(s) of ginger (500 mg/kg/day). Sections of frontal cortex, dentate gyrus, and cerebellum were stained with hematoxylin and eosin and examined using light microscopy. In addition, quantitative immunohistochemical assessments of the expression of inducible NO synthase (iNOS), tumor necrosis factor (TNF)-α, caspase-3, glial fibrillary acidic protein (GFAP), acetylcholinesterase (AChE), and Ki67 were performed. Our results revealed a protective role of ginger on the diabetic brain via reducing oxidative stress, apoptosis, and inflammation. In addition, this study revealed that the beneficial effect of ginger was also mediated by modulating the astroglial response to the injury, reducing AChE expression, and improving neurogenesis. These results represent a new insight into the beneficial effects of ginger on the structural alterations of diabetic brain and suggest that ginger might be a potential therapeutic strategy for the treatment of diabetic-induced damage in brain. Copyright © 2014 Elsevier GmbH. All rights reserved.

The neurobiological role of the dorsolateral prefrontal cortex in recovery from trauma. Longitudinal brain imaging study among survivors of the South Korean subway disaster.

PubMed

Lyoo, In Kyoon; Kim, Jieun E; Yoon, Sujung J; Hwang, Jaeuk; Bae, Sujin; Kim, Dajung J

2011-07-01

A multiwave longitudinal neuroimaging study in a cohort of direct survivors of a South Korean subway disaster, most of whom recovered from posttraumatic stress disorder 5 years after trauma, provided a unique opportunity to investigate the brain correlates of recovery from a severe psychological trauma. To investigate region-specific brain mobilization during successful recovery from posttraumatic stress disorder by assessing cortical thickness multiple times from early after trauma to recovery, and to examine whether a brain-derived neurotrophic factor gene polymorphism was associated with this brain mobilization. Five-year follow-up case-control study conducted from 2003-2007. Seoul National University and Hospital. Thirty psychologically traumatized disaster survivors and 36 age- and sex-matched control group members recruited from the disaster registry and local community, respectively, who contributed 156 high-resolution brain magnetic resonance images during 3 waves of assessments. Cerebral cortical thickness measured in high-resolution anatomic magnetic resonance images using a validated cortical thickness analysis tool and its prospective changes from early after trauma to recovery in trauma-exposed individuals and controls. Trauma-exposed individuals had greater dorsolateral prefrontal cortical (DLPFC) thickness 1.42 years after trauma (right DLPFC, 5.4%; left superior frontal cortex, 5.8%; and left inferior frontal cortex, 5.3% [all clusters, P ≤ .01]) relative to controls. Thicknesses gradually normalized over time during recovery. We found a positive linear trend, with trauma-exposed individuals with a valine/valine genotype having the greatest DLPFC cortical thickness, followed by those with a methionine genotype and controls (P < .001 for trend). Greater DLPFC thickness was associated with greater posttraumatic stress disorder symptom reductions and better recovery. The DLPFC region might play an important role in psychological recovery from a severely traumatic event in humans.

Amyloid tracers detect multiple binding sites in Alzheimer's disease brain tissue.

PubMed

Ni, Ruiqing; Gillberg, Per-Göran; Bergfors, Assar; Marutle, Amelia; Nordberg, Agneta

2013-07-01

Imaging fibrillar amyloid-β deposition in the human brain in vivo by positron emission tomography has improved our understanding of the time course of amyloid-β pathology in Alzheimer's disease. The most widely used amyloid-β imaging tracer so far is (11)C-Pittsburgh compound B, a thioflavin derivative but other (11)C- and (18)F-labelled amyloid-β tracers have been studied in patients with Alzheimer's disease and cognitively normal control subjects. However, it has not yet been established whether different amyloid tracers bind to identical sites on amyloid-β fibrils, offering the same ability to detect the regional amyloid-β burden in the brains. In this study, we characterized (3)H-Pittsburgh compound B binding in autopsied brain regions from 23 patients with Alzheimer's disease and 20 control subjects (aged 50 to 88 years). The binding properties of the amyloid tracers FDDNP, AV-45, AV-1 and BF-227 were also compared with those of (3)H-Pittsburgh compound B in the frontal cortices of patients with Alzheimer's disease. Saturation binding studies revealed the presence of high- and low-affinity (3)H-Pittsburgh compound B binding sites in the frontal cortex (K(d1): 3.5 ± 1.6 nM; K(d2): 133 ± 30 nM) and hippocampus (K(d1):5.6 ± 2.2 nM; K(d2): 181 ± 132 nM) of Alzheimer's disease brains. The relative proportion of high-affinity to low-affinity sites was 6:1 in the frontal cortex and 3:1 in the hippocampus. One control showed both high- and low-affinity (3)H-Pittsburgh compound B binding sites (K(d1): 1.6 nM; K(d2): 330 nM) in the cortex while the others only had a low-affinity site (K(d2): 191 ± 70 nM). (3)H-Pittsburgh compound B binding in Alzheimer's disease brains was higher in the frontal and parietal cortices than in the caudate nucleus and hippocampus, and negligible in the cerebellum. Competitive binding studies with (3)H-Pittsburgh compound B in the frontal cortices of Alzheimer's disease brains revealed high- and low-affinity binding sites for BTA-1 (Ki: 0.2 nM, 70 nM), florbetapir (1.8 nM, 53 nM) and florbetaben (1.0 nM, 65 nM). BF-227 displaced 83% of (3)H-Pittsburgh compound B binding, mainly at a low-affinity site (311 nM), whereas FDDNP only partly displaced (40%). We propose a multiple binding site model for the amyloid tracers (binding sites 1, 2 and 3), where AV-45 (florbetapir), AV-1 (florbetaben), and Pittsburgh compound B, all show nanomolar affinity for the high-affinity site (binding site 1), as visualized by positron emission tomography. BF-227 shows mainly binding to site 3 and FDDNP shows only some binding to site 2. Different amyloid tracers may provide new insight into the pathophysiological mechanisms in the progression of Alzheimer's disease.

Cognitive Functions and Neurodevelopmental Disorders Involving the Prefrontal Cortex and Mediodorsal Thalamus

PubMed Central

Ouhaz, Zakaria; Fleming, Hugo; Mitchell, Anna S.

2018-01-01

The mediodorsal nucleus of the thalamus (MD) has been implicated in executive functions (such as planning, cognitive control, working memory, and decision-making) because of its significant interconnectivity with the prefrontal cortex (PFC). Yet, whilst the roles of the PFC have been extensively studied, how the MD contributes to these cognitive functions remains relatively unclear. Recently, causal evidence in monkeys has demonstrated that in everyday tasks involving rapid updating (e.g., while learning something new, making decisions, or planning the next move), the MD and frontal cortex are working in close partnership. Furthermore, researchers studying the MD in rodents have been able to probe the underlying mechanisms of this relationship to give greater insights into how the frontal cortex and MD might interact during the performance of these essential tasks. This review summarizes the circuitry and known neuromodulators of the MD, and considers the most recent behavioral, cognitive, and neurophysiological studies conducted in monkeys and rodents; in total, this evidence demonstrates that MD makes a critical contribution to cognitive functions. We propose that communication occurs between the MD and the frontal cortex in an ongoing, fluid manner during rapid cognitive operations, via the means of efference copies of messages passed through transthalamic routes; the conductance of these messages may be modulated by other brain structures interconnected to the MD. This is similar to the way in which other thalamic structures have been suggested to carry out forward modeling associated with rapid motor responding and visual processing. Given this, and the marked thalamic pathophysiology now identified in many neuropsychiatric disorders, we suggest that changes in the different subdivisions of the MD and their interconnections with the cortex could plausibly give rise to a number of the otherwise disparate symptoms (including changes to olfaction and cognitive functioning) that are associated with many different neuropsychiatric disorders. In particular, we will focus here on the cognitive symptoms of schizophrenia and suggest testable hypotheses about how changes to MD-frontal cortex interactions may affect cognitive processes in this disorder. PMID:29467603

Longitudinal changes in cortical thickness in autism and typical development.

PubMed

Zielinski, Brandon A; Prigge, Molly B D; Nielsen, Jared A; Froehlich, Alyson L; Abildskov, Tracy J; Anderson, Jeffrey S; Fletcher, P Thomas; Zygmunt, Kristen M; Travers, Brittany G; Lange, Nicholas; Alexander, Andrew L; Bigler, Erin D; Lainhart, Janet E

2014-06-01

The natural history of brain growth in autism spectrum disorders remains unclear. Cross-sectional studies have identified regional abnormalities in brain volume and cortical thickness in autism, although substantial discrepancies have been reported. Preliminary longitudinal studies using two time points and small samples have identified specific regional differences in cortical thickness in the disorder. To clarify age-related trajectories of cortical development, we examined longitudinal changes in cortical thickness within a large mixed cross-sectional and longitudinal sample of autistic subjects and age- and gender-matched typically developing controls. Three hundred and forty-five magnetic resonance imaging scans were examined from 97 males with autism (mean age = 16.8 years; range 3-36 years) and 60 males with typical development (mean age = 18 years; range 4-39 years), with an average interscan interval of 2.6 years. FreeSurfer image analysis software was used to parcellate the cortex into 34 regions of interest per hemisphere and to calculate mean cortical thickness for each region. Longitudinal linear mixed effects models were used to further characterize these findings and identify regions with between-group differences in longitudinal age-related trajectories. Using mean age at time of first scan as a reference (15 years), differences were observed in bilateral inferior frontal gyrus, pars opercularis and pars triangularis, right caudal middle frontal and left rostral middle frontal regions, and left frontal pole. However, group differences in cortical thickness varied by developmental stage, and were influenced by IQ. Differences in age-related trajectories emerged in bilateral parietal and occipital regions (postcentral gyrus, cuneus, lingual gyrus, pericalcarine cortex), left frontal regions (pars opercularis, rostral middle frontal and frontal pole), left supramarginal gyrus, and right transverse temporal gyrus, superior parietal lobule, and paracentral, lateral orbitofrontal, and lateral occipital regions. We suggest that abnormal cortical development in autism spectrum disorders undergoes three distinct phases: accelerated expansion in early childhood, accelerated thinning in later childhood and adolescence, and decelerated thinning in early adulthood. Moreover, cortical thickness abnormalities in autism spectrum disorders are region-specific, vary with age, and may remain dynamic well into adulthood. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Brain glucose metabolism in an animal model of depression.

PubMed

Detka, J; Kurek, A; Kucharczyk, M; Głombik, K; Basta-Kaim, A; Kubera, M; Lasoń, W; Budziszewska, B

2015-06-04

An increasing number of data support the involvement of disturbances in glucose metabolism in the pathogenesis of depression. We previously reported that glucose and glycogen concentrations in brain structures important for depression are higher in a prenatal stress model of depression when compared with control animals. A marked rise in the concentrations of these carbohydrates and glucose transporters were evident in prenatally stressed animals subjected to acute stress and glucose loading in adulthood. To determine whether elevated levels of brain glucose are associated with a change in its metabolism in this model, we assessed key glycolytic enzymes (hexokinase, phosphofructokinase and pyruvate kinase), products of glycolysis, i.e., pyruvate and lactate, and two selected enzymes of the tricarboxylic acid cycle (pyruvate dehydrogenase and α-ketoglutarate dehydrogenase) in the hippocampus and frontal cortex. Additionally, we assessed glucose-6-phosphate dehydrogenase activity, a key enzyme in the pentose phosphate pathway (PPP). Prenatal stress increased the levels of phosphofructokinase, an important glycolytic enzyme, in the hippocampus and frontal cortex. However, prenatal stress had no effect on hexokinase or pyruvate kinase levels. The lactate concentration was elevated in prenatally stressed rats in the frontal cortex, and pyruvate levels remained unchanged. Among the tricarboxylic acid cycle enzymes, prenatal stress decreased the level of pyruvate dehydrogenase in the hippocampus, but it had no effect on α-ketoglutarate dehydrogenase. Like in the case of glucose and its transporters, also in the present study, differences in markers of glucose metabolism between control animals and those subjected to prenatal stress were not observed under basal conditions but in rats subjected to acute stress and glucose load in adulthood. Glucose-6-phosphate dehydrogenase activity was not reduced by prenatal stress but was found to be even higher in animals exposed to all experimental conditions, i.e., prenatal stress, acute stress, and glucose administration. Our data indicate that glycolysis is increased and the Krebs cycle is decreased in the brain of a prenatal stress animal model of depression. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Neural source dynamics of brain responses to continuous stimuli: Speech processing from acoustics to comprehension.

PubMed

Brodbeck, Christian; Presacco, Alessandro; Simon, Jonathan Z

2018-05-15

Human experience often involves continuous sensory information that unfolds over time. This is true in particular for speech comprehension, where continuous acoustic signals are processed over seconds or even minutes. We show that brain responses to such continuous stimuli can be investigated in detail, for magnetoencephalography (MEG) data, by combining linear kernel estimation with minimum norm source localization. Previous research has shown that the requirement to average data over many trials can be overcome by modeling the brain response as a linear convolution of the stimulus and a kernel, or response function, and estimating a kernel that predicts the response from the stimulus. However, such analysis has been typically restricted to sensor space. Here we demonstrate that this analysis can also be performed in neural source space. We first computed distributed minimum norm current source estimates for continuous MEG recordings, and then computed response functions for the current estimate at each source element, using the boosting algorithm with cross-validation. Permutation tests can then assess the significance of individual predictor variables, as well as features of the corresponding spatio-temporal response functions. We demonstrate the viability of this technique by computing spatio-temporal response functions for speech stimuli, using predictor variables reflecting acoustic, lexical and semantic processing. Results indicate that processes related to comprehension of continuous speech can be differentiated anatomically as well as temporally: acoustic information engaged auditory cortex at short latencies, followed by responses over the central sulcus and inferior frontal gyrus, possibly related to somatosensory/motor cortex involvement in speech perception; lexical frequency was associated with a left-lateralized response in auditory cortex and subsequent bilateral frontal activity; and semantic composition was associated with bilateral temporal and frontal brain activity. We conclude that this technique can be used to study the neural processing of continuous stimuli in time and anatomical space with the millisecond temporal resolution of MEG. This suggests new avenues for analyzing neural processing of naturalistic stimuli, without the necessity of averaging over artificially short or truncated stimuli. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of dopaminergic genes, prenatal adversities, and their interaction on attention-deficit/hyperactivity disorder and neural correlates of response inhibition.

PubMed

van der Meer, Dennis; Hartman, Catharina A; van Rooij, Daan; Franke, Barbara; Heslenfeld, Dirk J; Oosterlaan, Jaap; Faraone, Stephen V; Buitelaar, Jan K; Hoekstra, Pieter J

2017-03-01

Attention-deficit/hyperactivity disorder (ADHD) is often accompanied by impaired response inhibition; both have been associated with aberrant dopamine signalling. Given that prenatal exposure to alcohol or smoking is known to affect dopamine-rich brain regions, we hypothesized that individuals carrying the ADHD risk alleles of the dopamine receptor D4 ( DRD4 ) and dopamine transporter ( DAT1 ) genes may be especially sensitive to their effects. Functional MRI data, information on prenatal adversities and genetic data were available for 239 adolescents and young adults participating in the multicentre ADHD cohort study NeuroIMAGE (average age 17.3 yr). We analyzed the effects of DRD4 and DAT1 , prenatal exposure to alcohol and smoking and their interactions on ADHD severity, response inhibition and neural activity. We found no significant gene × environment interaction effects. We did find that the DRD4 7-repeat allele was associated with less superior frontal and parietal brain activity and with greater activity in the frontal pole and occipital cortex. Prenatal exposure to smoking was also associated with lower superior frontal activity, but with greater activity in the parietal lobe. Further, those exposed to alcohol had more activity in the lateral orbitofrontal cortex, and the DAT1 risk variant was associated with lower cerebellar activity. Retrospective reports of maternal substance use and the cross-sectional study design restrict causal inference. While we found no evidence of gene × environment interactions, the risk factors under investigation influenced activity of brain regions associated with response inhibition, suggesting they may add to problems with inhibiting behaviour.

Abnormal functional connectivity density in children with anisometropic amblyopia at resting-state.

PubMed

Wang, Tianyue; Li, Qian; Guo, Mingxia; Peng, Yanmin; Li, Qingji; Qin, Wen; Yu, Chunshui

2014-05-14

Amblyopia is a developmental disorder resulting from anomalous binocular visual input in early life. Task-based neuroimaging studies have widely investigated cortical functional impairments in amblyopia, but changes in spontaneous neuronal functional activities in amblyopia remain largely unknown. In the present study, functional connectivity density (FCD) mapping, an ultrafast data-driven method based on fMRI, was applied for the first time to investigate changes in cortical functional connectivities in amblyopia during the resting-state. We quantified and compared both short- and long-range FCD in both the brains of children with anisometropic amblyopia (AAC) and normal sighted children (NSC). In contrast to the NSC, the AAC showed significantly decreased short-range FCD in the inferior temporal/fusiform gyri, parieto-occipital and rostrolateral prefrontal cortices, as well as decreased long-range FCD in the premotor cortex, dorsal inferior parietal lobule, frontal-insular and dorsal prefrontal cortices. Furthermore, most regions with reduced long-range FCD in the AAC showed decreased functional connectivity with occipital and posterior parietal cortices in the AAC. The results suggest that chronically poor visual input in amblyopia not only impairs the brain's short-range functional connections in visual pathways and in the frontal cortex, which is important for cognitive control, but also affects long-range functional connections among the visual areas, posterior parietal and frontal cortices that subserve visuomotor and visual-guided actions, visuospatial attention modulation and the integration of salient information. This study provides evidence for abnormal spontaneous brain activities in amblyopia. Copyright © 2014 Elsevier B.V. All rights reserved.

Personality traits modulate subcortical and cortical vestibular and anxiety responses to sound-evoked otolithic receptor stimulation.

PubMed

Indovina, Iole; Riccelli, Roberta; Staab, Jeffrey P; Lacquaniti, Francesco; Passamonti, Luca

2014-11-01

Strong links between anxiety, space-motion perception, and vestibular symptoms have been recognized for decades. These connections may extend to anxiety-related personality traits. Psychophysical studies showed that high trait anxiety affected postural control and visual scanning strategies under stress. Neuroticism and introversion were identified as risk factors for chronic subjective dizziness (CSD), a common psychosomatic syndrome. This study examined possible relationships between personality traits and activity in brain vestibular networks for the first time using functional magnetic resonance imaging (fMRI). Twenty-six right-handed healthy individuals underwent fMRI during sound-evoked vestibular stimulation. Regional brain activity and functional connectivity measures were correlated with personality traits of the Five Factor Model (neuroticism, extraversion-introversion, openness, agreeableness, consciousness). Neuroticism correlated positively with activity in the pons, vestibulo-cerebellum, and para-striate cortex, and negatively with activity in the supra-marginal gyrus. Neuroticism also correlated positively with connectivity between pons and amygdala, vestibulo-cerebellum and amygdala, inferior frontal gyrus and supra-marginal gyrus, and inferior frontal gyrus and para-striate cortex. Introversion correlated positively with amygdala activity and negatively with connectivity between amygdala and inferior frontal gyrus. Neuroticism and introversion correlated with activity and connectivity in cortical and subcortical vestibular, visual, and anxiety systems during vestibular stimulation. These personality-related changes in brain activity may represent neural correlates of threat sensitivity in posture and gaze control mechanisms in normal individuals. They also may reflect risk factors for anxiety-related morbidity in patients with vestibular disorders, including previously observed associations of neuroticism and introversion with CSD. Copyright © 2014 Elsevier Inc. All rights reserved.

Income change alters default mode network connectivity for adolescents in poverty.

PubMed

Weissman, David G; Conger, Rand D; Robins, Richard W; Hastings, Paul D; Guyer, Amanda E

2018-04-01

Experiencing poverty during childhood and adolescence may affect brain function. However, income is dynamic, and studies have not addressed whether income change relates to brain function. In the present study, we investigated whether intrinsic functional connectivity of default mode network (DMN) regions was influenced by mean family income and family income change. Parents of 68 Mexican-origin adolescents (35 females) reported family income annually when adolescents were 10-16 years old. Intercept and slope of income at each of these ages were calculated for each participant. At age 16 years, adolescents completed a resting state functional neuroimaging scan. Adolescents from high and low income families did not differ in their functional connectivity, but for adolescents in families with lower incomes, their connectivity patterns depended on their income slope. Low-income adolescents whose income increased demonstrated greater connectivity between the posterior cingulate cortex (PCC) and the medial prefrontal cortex (mPFC), both DMN regions, and between the PCC and the right inferior frontal gyrus. Increases in income were associated with greater connectivity of the mPFC with the right inferior frontal gyrus and the left superior parietal lobule regardless of mean income. Increases in income, especially among adolescents in poverty, may alleviate stressors, influencing the development of brain networks. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Imitating expressions: emotion-specific neural substrates in facial mimicry.

PubMed

Lee, Tien-Wen; Josephs, Oliver; Dolan, Raymond J; Critchley, Hugo D

2006-09-01

Intentionally adopting a discrete emotional facial expression can modulate the subjective feelings corresponding to that emotion; however, the underlying neural mechanism is poorly understood. We therefore used functional brain imaging (functional magnetic resonance imaging) to examine brain activity during intentional mimicry of emotional and non-emotional facial expressions and relate regional responses to the magnitude of expression-induced facial movement. Eighteen healthy subjects were scanned while imitating video clips depicting three emotional (sad, angry, happy), and two 'ingestive' (chewing and licking) facial expressions. Simultaneously, facial movement was monitored from displacement of fiducial markers (highly reflective dots) on each subject's face. Imitating emotional expressions enhanced activity within right inferior prefrontal cortex. This pattern was absent during passive viewing conditions. Moreover, the magnitude of facial movement during emotion-imitation predicted responses within right insula and motor/premotor cortices. Enhanced activity in ventromedial prefrontal cortex and frontal pole was observed during imitation of anger, in ventromedial prefrontal and rostral anterior cingulate during imitation of sadness and in striatal, amygdala and occipitotemporal during imitation of happiness. Our findings suggest a central role for right inferior frontal gyrus in the intentional imitation of emotional expressions. Further, by entering metrics for facial muscular change into analysis of brain imaging data, we highlight shared and discrete neural substrates supporting affective, action and social consequences of somatomotor emotional expression.

The effect of enriched environment across ages: A study of anhedonia and BDNF gene induction.

PubMed

Dong, B E; Xue, Y; Sakata, K

2018-05-02

Enriched environment treatment (EET) is a potential intervention for depression by inducing brain-derived neurotrophic factor (BDNF). However, its age dependency remains unclear. We recently found that EET during early-life development (ED) was effective in increasing exploratory activity and anti-despair behavior, particularly in promoter IV-driven BDNF deficient mice (KIV), with the largest BDNF protein induction in the hippocampus and frontal cortex. Here, we further determined age dependency of EET effects on anhedonia and promoter-specific BDNF transcription, by using the sucrose preference test and qRT-PCR. Wild-type (WT) and KIV mice received 2 months of EET during ED, young-adulthood and old-adulthood (0-2, 2-4 and 12-14 months, respectively). All KIV groups showed reduced sucrose preference, which EET equally reversed regardless of age. EET increased hippocampal BDNF mRNA levels for all ages and genotypes, but increased frontal cortex BDNF mRNA levels only in ED KIV and old WT mice. Transcription by promoters I and IV was age-dependent in the hippocampus of WT mice: more effective induction of exon IV or I during ED or old-adulthood, respectively. Transcription by almost all 9 promoters was age-specific in the frontal cortex, mostly observed in ED KIV mice. After discontinuance of EET, the EET effects on anti-anhedonia and BDNF transcription in both regions persisted only in ED KIV mice. These results suggested that EET was equally effective in reversing anhedonia and inducing hippocampal BDNF transcription, but was more effective during ED in inducing frontal cortex BDNF transcription and for lasting anti-anhedonic and BDNF effects particularly in promoter IV-BDNF deficiency. © 2018 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Neuroprotective efficacy of curcumin in arsenic induced cholinergic dysfunctions in rats.

PubMed

Yadav, Rajesh S; Chandravanshi, Lalit P; Shukla, Rajendra K; Sankhwar, Madhu L; Ansari, Reyaz W; Shukla, Pradeep K; Pant, Aditya B; Khanna, Vinay K

2011-12-01

Our recent studies have shown that curcumin protects arsenic induced neurotoxicity by modulating oxidative stress, neurotransmitter levels and dopaminergic system in rats. As chronic exposure to arsenic has been associated with cognitive deficits in humans, the present study has been carried out to implore the neuroprotective potential of curcumin in arsenic induced cholinergic dysfunctions in rats. Rats treated with arsenic (sodium arsenite, 20mg/kg body weight, p.o., 28 days) exhibited a significant decrease in the learning activity, assessed by passive avoidance response associated with decreased binding of (3)H-QNB, known to label muscarinic-cholinergic receptors in hippocampus (54%) and frontal cortex (27%) as compared to controls. Decrease in the activity of acetylcholinesterase in hippocampus (46%) and frontal cortex (33%), staining of Nissl body, immunoreactivity of choline acetyltransferase (ChAT) and expression of ChAT protein in hippocampal region was also observed in arsenic treated rats as compared to controls. Simultaneous treatment with arsenic and curcumin (100mg/kg body weight, p.o., 28 days) increased learning and memory performance associated with increased binding of (3)H-QNB in hippocampus (54%), frontal cortex (25%) and activity of acetylcholinesterase in hippocampus (41%) and frontal cortex (29%) as compared to arsenic treated rats. Increase in the expression of ChAT protein, immunoreactivity of ChAT and staining of Nissl body in hippocampal region was also observed in rats simultaneously treated with arsenic and curcumin as compared to those treated with arsenic alone. The results of the present study suggest that curcumin significantly modulates arsenic induced cholinergic dysfunctions in brain and also exhibits neuroprotective efficacy of curcumin. Copyright © 2011 Elsevier Inc. All rights reserved.

Alterations in amino acid levels in mouse brain regions after adjunctive treatment of brexpiprazole with fluoxetine: comparison with (R)-ketamine.

PubMed

Ma, Min; Ren, Qian; Fujita, Yuko; Yang, Chun; Dong, Chao; Ohgi, Yuta; Futamura, Takashi; Hashimoto, Kenji

2017-11-01

Brexpiprazole, a serotonin-dopamine activity modulator, is approved in the USA as an adjunctive therapy to antidepressants for treating major depressive disorders. Similar to the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine, the combination of brexpiprazole and fluoxetine has demonstrated antidepressant-like effects in animal models of depression. The present study was conducted to examine whether the combination of brexpiprazole and fluoxetine could affect the tissue levels of amino acids [glutamate, glutamine, γ-aminobutyric acid (GABA), D-serine, L-serine, and glycine] that are associated with NMDAR neurotransmission. The tissue levels of amino acids in the frontal cortex, striatum, hippocampus, and cerebellum were measured after a single [or repeated (14 days)] oral administration of vehicle, fluoxetine (10 mg/kg), brexpiprazole (0.1 mg/kg), or a combination of the two drugs. Furthermore, we measured the tissue levels of amino acids after a single administration of the NMDAR antagonist (R)-ketamine. A single injection of the combination of fluoxetine and brexpiprazole significantly increased GABA levels in the striatum, the D-serine/L-serine ratio in the frontal cortex, and the glycine/L-serine ratio in the hippocampus. A repeated administration of the combination significantly altered the tissue levels of amino acids in all regions. Interestingly, a repeated administration of the combination significantly decreased the D-serine/L-serine ratio in the frontal cortex, striatum, and hippocampus. In contrast, a single administration of (R)-ketamine significantly increased the D-serine/L-serine ratio in the frontal cortex. These results suggested that alterations in the tissue levels of these amino acids may be involved in the antidepressant-like effects of the combination of brexpiprazole and fluoxetine.

Neural correlates of continuous causal word generation.

PubMed

Wende, Kim C; Straube, Benjamin; Stratmann, Mirjam; Sommer, Jens; Kircher, Tilo; Nagels, Arne

2012-09-01

Causality provides a natural structure for organizing our experience and language. Causal reasoning during speech production is a distinct aspect of verbal communication, whose related brain processes are yet unknown. The aim of the current study was to investigate the neural mechanisms underlying the continuous generation of cause-and-effect coherences during overt word production. During fMRI data acquisition participants performed three verbal fluency tasks on identical cue words: A novel causal verbal fluency task (CVF), requiring the production of multiple reasons to a given cue word (e.g. reasons for heat are fire, sun etc.), a semantic (free association, FA, e.g. associations with heat are sweat, shower etc.) and a phonological control task (phonological verbal fluency, PVF, e.g. rhymes with heat are meat, wheat etc.). We found that, in contrast to PVF, both CVF and FA activated a left lateralized network encompassing inferior frontal, inferior parietal and angular regions, with further bilateral activation in middle and inferior as well as superior temporal gyri and the cerebellum. For CVF contrasted against FA, we found greater bold responses only in the left middle frontal cortex. Large overlaps in the neural activations during free association and causal verbal fluency indicate that the access to causal relationships between verbal concepts is at least partly based on the semantic neural network. The selective activation in the left middle frontal cortex for causal verbal fluency suggests that distinct neural processes related to cause-and-effect-relations are associated with the recruitment of middle frontal brain areas. Copyright © 2012 Elsevier Inc. All rights reserved.

Differences in Cerebral Perfusion Deficits in Mild Traumatic Brain Injury and Depression Using Single-Photon Emission Computed Tomography

PubMed Central

Romero, Kristoffer; Black, Sandra E.; Feinstein, Anthony

2014-01-01

Background: Numerous studies have shown decreased perfusion in the prefrontal cortex following mild traumatic brain injury (mTBI). However, similar hypoperfusion can also be observed in depression. Given the high prevalence of depressive symptoms following mTBI, it is unclear to what extent depression influences hypoperfusion in TBI. Methods: Mild TBI patients without depressive symptoms (mTBI-noD, n = 39), TBI patients with depressive symptoms (mTBI-D, n = 13), and 15 patients with major depressive disorder (MDD), but no TBI were given 99m T-ECD single-photon emission computed tomography (SPECT) scans within 2 weeks of injury. All subjects completed tests of information processing speed, complex attention, and executive functioning, and a self-report questionnaire measuring symptoms of psychological distress. Between-group comparisons of quantified SPECT perfusion were undertaken using univariate and multivariate (partial least squares) analyses. Results: mTBI-D and mTBI-noD groups did not differ in terms of cerebral perfusion. However, patients with MDD showed hypoperfusion compared to both TBI groups in several frontal (orbitofrontal, middle frontal, and superior frontal cortex), superior temporal, and posterior cingulate regions. The mTBI-D group showed poorer performance on a measure of complex attention and working memory compared to both the mTBI-noD and MDD groups. Conclusion: These results suggest that depressive symptoms do not affect SPECT perfusion in the sub-acute phase following a mild TBI. Conversely, MDD is associated with hypoperfusion primarily in frontal regions. PMID:25191305

A Comparative Magnetic Resonance Imaging Study of the Anatomy, Variability, and Asymmetry of Broca's Area in the Human and Chimpanzee Brain

PubMed Central

Keller, Simon S.; Roberts, Neil; Hopkins, William

2009-01-01

The frontal operculum—classically considered to be Broca's area—has special significance and interest in clinical, cognitive, and comparative neuroscience given its role in spoken language and the long-held assumption that structural asymmetry of this region of cortex may be related to functional lateralization of human language. We performed a detailed morphological and morphometric analysis of this area of the brain in humans and chimpanzees using identical image acquisition parameters, image analysis techniques, and consistent anatomical boundaries in both species. We report great inter-individual variability of the sulcal contours defining the operculum in both species, particularly discontinuity of the inferior frontal sulcus in humans and bifurcation of the inferior precentral sulcus in chimpanzees. There was no evidence of population-based asymmetry of the frontal opercular gray matter in humans or chimpanzees. The diagonal sulcus was only identified in humans, and its presence was significantly (F = 12.782, p < 0.001) associated with total volume of the ipsilateral operculum. The findings presented here suggest that there is no population-based interhemispheric macroscopic asymmetry of Broca's area in humans or Broca's area homolog in chimpanzees. However, given that previous studies have reported asymmetry in the cytoarchitectonic fields considered to represent Broca's area—which is important given that cytoarchitectonic boundaries are more closely related to the regional functional properties of cortex relative to sulcal landmarks—it may be that the gross morphology of the frontal operculum is not a reliable indicator of Broca's area per se. PMID:19923293

Effects of acupuncture on tissue oxygenation of the rat brain.

PubMed

Chen, G S; Erdmann, W

1978-04-01

Acupuncture has been claimed to be effective in restoring consciousness in some comatose patients. Possible mechanisms to explain alleged acupuncture-induced arousal may include vasodilatory effects caused by smypathetic stimulation which leads to an augmentation of cerebral microcirculation and thereby improves oxygen supply to the brain tissue. Experiments were performed in ten albino rats (Wistar) employing PO2 microelectrodes which were inserted into the cortex through small burholes. Brain tissue PO2 was continuously recorded before, during, and after acupuncture. Stimulation of certain acupuncture points (Go-26) resulted in immediate increase of PO2 in the frontal cortex of the rat brain. This effect was reproducible and was comparable to that obtained with increase of inspiratory CO2 known to induce arterial vasodilatation and thus capillary perfusion pressure. The effect was more significant as compared to tissue PO2 increases obtained after increase in inspiratory oxygen concentration from 21% to 100%. It appears that acupuncture causes increased brain tissue perfusion which may be, at least in part, responsible for arousal of unconscious patients.

Left dorsolateral prefrontal cortex atrophy is associated with frontal lobe function in Alzheimer's disease and contributes to caregiver burden.

PubMed

Matsuoka, Kiwamu; Yasuno, Fumihiko; Hashimoto, Akiko; Miyasaka, Toshiteru; Takahashi, Masato; Kiuchi, Kuniaki; Iida, Junzo; Kichikawa, Kimihiko; Kishimoto, Toshifumi

2018-05-01

Caregivers of patients with dementia experience physical and mental deterioration. We have previously reported a correlation between caregiver burden and the Frontal Assessment Battery (FAB) total scores of patients with Alzheimer's disease (AD), especially regarding the dependency factor from the Zarit Burden Interview. The present study aimed to identify an objective biomarker for predicting caregiver burden. The participants were 26 pairs of caregivers and patients with AD and mild-to-moderate dementia. Correlations between regional gray matter volumes in the patients with AD and the FAB total scores were explored by using whole-brain voxel-based morphometric analysis. Path analysis was used to estimate the relationships between regional gray matter volumes, FAB total scores, and caregiver burden based on the Zarit Burden Interview. The voxel-based morphometric revealed a significant positive correlation between the FAB total scores and the volume of the left dorsolateral prefrontal cortex. This positive correlation persisted after controlling for the effect of general cognitive dysfunction, which was assessed by using the Mini-Mental State Examination. Path analysis revealed that decreases in FAB scores, caused by reduced frontal lobe volumes, negatively affected caregiver burden. The present study revealed that frontal lobe function, based on FAB scores, was affected by the volume of the left dorsolateral prefrontal cortex. Decreased scores were associated with greater caregiver burden, especially for the dependency factor. These findings may facilitate the development of an objective biomarker for predicting caregiver burden. Copyright © 2017 John Wiley & Sons, Ltd.

Brain imaging studies of the cocaine addict: Implications for reinforcement and addiction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Volkow, N.D.; Fowler, J.S.

1995-07-01

These studies document dopaminergic abnormalities in cocaine abusers. They also suggest a regulatory role of Dopamine (DA) in frontal metabolism. The correlation of striatal D{sub 2} receptor availability with metabolism was strongest for orbital frontal cortex (OFC) cingulate and prefrontal cortices. In cocaine abusers tested during early withdrawal (<1 week) the OFC was found to be hypermetabolic and metabolism in OFC and prefrontal cortices were found to be significantly associated with cocaine craving . Thus, we postulate that repeated and intermittent DA stimulation, as seen during a cocaine binge, activates the prefrontal and OFC cortices increasing the drive to compulsivelymore » self-administer cocaine. During cocaine discontinuation and protracted withdrawal and with decreased DA stimulation, these frontal cortical regions become hyponietabolic. Dopaminergic stimulation by a DA-enhancing drug and/or environmental conditioning will reactivate these frontal regions resetting the compulsion to self-administer cocaine and the inability to terminate this behavior. The pharmacokionetic studies with [11C]cocaine are consistent with behavioral and pharmacological studies in animals as well as in vitro studies which have revealed that while the mechanisms for cocaine`s reinforcing properties are complex, they partly involve the brain`s dopamine system and also highlight the importance of cocaine`s pharmacokinetic on its unique reinforcing properties.« less

Whole-brain MRI phenotyping in dysplasia-related frontal lobe epilepsy.

PubMed

Hong, Seok-Jun; Bernhardt, Boris C; Schrader, Dewi S; Bernasconi, Neda; Bernasconi, Andrea

2016-02-16

To perform whole-brain morphometry in patients with frontal lobe epilepsy and evaluate the utility of group-level patterns for individualized diagnosis and prognosis. We compared MRI-based cortical thickness and folding complexity between 2 frontal lobe epilepsy cohorts with histologically verified focal cortical dysplasia (FCD) (13 type I; 28 type II) and 41 closely matched controls. Pattern learning algorithms evaluated the utility of group-level findings to predict histologic FCD subtype, the side of the seizure focus, and postsurgical seizure outcome in single individuals. Relative to controls, FCD type I displayed multilobar cortical thinning that was most marked in ipsilateral frontal cortices. Conversely, type II showed thickening in temporal and postcentral cortices. Cortical folding also diverged, with increased complexity in prefrontal cortices in type I and decreases in type II. Group-level findings successfully guided automated FCD subtype classification (type I: 100%; type II: 96%), seizure focus lateralization (type I: 92%; type II: 86%), and outcome prediction (type I: 92%; type II: 82%). FCD subtypes relate to diverse whole-brain structural phenotypes. While cortical thickening in type II may indicate delayed pruning, a thin cortex in type I likely results from combined effects of seizure excitotoxicity and the primary malformation. Group-level patterns have a high translational value in guiding individualized diagnostics. © 2016 American Academy of Neurology.

An Increase in Postural Load Facilitates an Anterior Shift of Processing Resources to Frontal Executive Function in a Postural-Suprapostural Task

PubMed Central

Huang, Cheng-Ya; Chang, Gwo-Ching; Tsai, Yi-Ying; Hwang, Ing-Shiou

2016-01-01

Increase in postural-demand resources does not necessarily degrade a concurrent motor task, according to the adaptive resource-sharing hypothesis of postural-suprapostural dual-tasking. This study investigated how brain networks are organized to optimize a suprapostural motor task when the postural load increases and shifts postural control into a less automatic process. Fourteen volunteers executed a designated force-matching task from a level surface (a relative automatic process in posture) and from a stabilometer board while maintaining balance at a target angle (a relatively controlled process in posture). Task performance of the postural and suprapostural tasks, synchronization likelihood (SL) of scalp EEG, and graph-theoretical metrics were assessed. Behavioral results showed that the accuracy and reaction time of force-matching from a stabilometer board were not affected, despite a significant increase in postural sway. However, force-matching in the stabilometer condition showed greater local and global efficiencies of the brain networks than force-matching in the level-surface condition. Force-matching from a stabilometer board was also associated with greater frontal cluster coefficients, greater mean SL of the frontal and sensorimotor areas, and smaller mean SL of the parietal-occipital cortex than force-matching from a level surface. The contrast of supra-threshold links in the upper alpha and beta bands between the two stance conditions validated load-induced facilitation of inter-regional connections between the frontal and sensorimotor areas, but that contrast also indicated connection suppression between the right frontal-temporal and the parietal-occipital areas for the stabilometer stance condition. In conclusion, an increase in stance difficulty alters the neurocognitive processes in executing a postural-suprapostural task. Suprapostural performance is not degraded by increase in postural load, due to (1) increased effectiveness of information transfer, (2) an anterior shift of processing resources toward frontal executive function, and (3) cortical dissociation of control hubs in the parietal-occipital cortex for neural economy. PMID:27594830

Visual food stimulus changes resting oscillatory brain activities related to appetitive motive.

PubMed

Yoshikawa, Takahiro; Tanaka, Masaaki; Ishii, Akira; Yamano, Yoko; Watanabe, Yasuyoshi

2016-09-26

Changes of resting brain activities after visual food stimulation might affect the feeling of pleasure in eating food in daily life and spontaneous appetitive motives. We used magnetoencephalography (MEG) to identify brain areas related to the activity changes. Fifteen healthy, right-handed males [age, 25.4 ± 5.5 years; body mass index, 22.5 ± 2.7 kg/m 2 (mean ± SD)] were enrolled. They were asked to watch food or mosaic pictures for 5 min and to close their eyes for 3 min before and after the picture presentation without thinking of anything. Resting brain activities were recorded during two eye-closed sessions. The feeling of pleasure in eating food in daily life and appetitive motives in the study setting were assessed by visual analogue scale (VAS) scores. The γ-band power of resting oscillatory brain activities was decreased after the food picture presentation in the right insula [Brodmann's area (BA) 13], the left orbitofrontal cortex (OFC) (BA11), and the left frontal pole (BA10). Significant reductions of the α-band power were observed in the dorsolateral prefrontal cortex (DLPFC) (BA46). Particularly, the feeling of pleasure in eating food was positively correlated with the power decrease in the insula and negatively with that in the DLPFC. The changes in appetitive motives were associated with the power decrease in the frontal pole. These findings suggest automatic brain mechanics whereby changes of the resting brain activity might be associated with positive feeling in dietary life and have an impact on the irresistible appetitive motives through emotional and cognitive brain functions.

New insights in the homotopic and heterotopic connectivity of the frontal portion of the human corpus callosum revealed by microdissection and diffusion tractography.

PubMed

De Benedictis, Alessandro; Petit, Laurent; Descoteaux, Maxime; Marras, Carlo Efisio; Barbareschi, Mattia; Corsini, Francesco; Dallabona, Monica; Chioffi, Franco; Sarubbo, Silvio

2016-12-01

Extensive studies revealed that the human corpus callosum (CC) plays a crucial role in providing large-scale bi-hemispheric integration of sensory, motor and cognitive processing, especially within the frontal lobe. However, the literature lacks of conclusive data regarding the structural macroscopic connectivity of the frontal CC. In this study, a novel microdissection approach was adopted, to expose the frontal fibers of CC from the dorsum to the lateral cortex in eight hemispheres and in one entire brain. Post-mortem results were then combined with data from advanced constrained spherical deconvolution in 130 healthy subjects. We demonstrated as the frontal CC provides dense inter-hemispheric connections. In particular, we found three types of fronto-callosal fibers, having a dorso-ventral organization. First, the dorso-medial CC fibers subserve homotopic connections between the homologous medial cortices of the superior frontal gyrus. Second, the ventro-lateral CC fibers subserve homotopic connections between lateral frontal cortices, including both the middle frontal gyrus and the inferior frontal gyrus, as well as heterotopic connections between the medial and lateral frontal cortices. Third, the ventro-striatal CC fibers connect the medial and lateral frontal cortices with the contralateral putamen and caudate nucleus. We also highlighted an intricate crossing of CC fibers with the main association pathways terminating in the lateral regions of the frontal lobes. This combined approach of ex vivo microdissection and in vivo diffusion tractography allowed demonstrating a previously unappreciated three-dimensional architecture of the anterior frontal CC, thus clarifying the functional role of the CC in mediating the inter-hemispheric connectivity. Hum Brain Mapp 37:4718-4735, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effects of rolipram, a phosphodiesterase 4 inhibitor, in combination with imipramine on depressive behavior, CRE-binding activity and BDNF level in learned helplessness rats.

PubMed

Itoh, Tetsuji; Tokumura, Miwa; Abe, Kohji

2004-09-13

The brain cAMP regulating system and its downstream elements play a pivotal role in the therapeutic effects of antidepressants. We previously reported the increase in activities of phosphodiesterase 4, a major phosphodiesterase isozyme hydrolyzing cAMP, in the frontal cortex and hippocampus of learned helplessness rats, an animal model for depression. The present study was undertaken to examine the combination of effects of rolipram, a phosphodiesterase 4 inhibitor, with imipramine, a typical tricyclic antidepressant, on depressive behavior in learned helplessness rats. Concurrently, cAMP-response element (CRE)-binding activity and brain-derived neurotrophic factor (BDNF) levels related to the therapeutic effects of antidepressants were determined. Repeated administration of imipramine (1.25-10 mg/kg, i.p.) or rolipram (1.25 mg/kg, i.p.) reduced the number of escape failures in learned helplessness rats. Imipramine could not completely ameliorate the escape behavior to a level similar to that of non-stressed rats even at 10 mg/kg. However, repeated coadministration of rolipram with imipramine (1.25 and 2.5 mg/kg, respectively) almost completely eliminated the escape failures in learned helplessness rats. The reduction of CRE-binding activities and BDNF levels in the frontal cortex or hippocampus in learned helplessness rats were ameliorated by treatment with imipramine or rolipram alone. CRE-binding activities and/or BDNF levels of the frontal cortex and hippocampus were significantly increased by treatment with a combination of rolipram and imipramine compared to those in imipramine-treated rats. These results indicated that coadministration of phosphodiesterase type 4 inhibitors with antidepressants may be more effective for depression therapy and suggest that elevation of the cAMP signal transduction pathway is involved in the antidepressive effects.

Neuropsychology of humor: an introduction. Part II. Humor and the brain.

PubMed

Derouesné, Christian

2016-09-01

Impairment of the perception or comprehension of humor is observed in patients with focal brain lesions in both hemispheres, but mainly in the right frontal lobe. Studies by functional magnetic resonance imaging in healthy subjects show that humor is associated with activation of two main neural systems in both hemispheres. The detection and resolution of incongruity, cognitive groundings of humor, are associated with activation of the medial prefrontal and temporoparietal cortex, and the humor appreciation with activation of the orbito-frontal and insular cortex, amygdala and the brain reward system. However, activation of these areas is not humor-specific and can be observed in various cognitive or emotional processes. Event-related potential studies confirm the involvement of both hemispheres in humor processing, and suggest that left prefrontal area is associated with joke comprehension and right prefrontal area with the resolution stage. Humor thus appears to be a complex and dynamic functional process involving, on one hand, two specialized but not specific neural systems linked to humor apprehension and appreciation, and, on the other hand, multiple interconnected functional brain networks including neural patterns underlying the moral framework and belief system, acquired by conditioning or imitation during the cognitive development and social interactions of the individual, and more distributed systems associated with the analysis of the current context of humor occurrence. Disturbances of the sense of humor could then result from focal brain alterations localized in one or two of the specialized areas underlying the comprehension or appreciation of humor, or from perturbations of the network interconnectivity in non-focal brain disorders such as Alzheimer's disease or schizophrenia.

Changes in Regional Brain Homogeneity Induced by Electro-Acupuncture Stimulation at the Baihui Acupoint in Healthy Subjects: A Functional Magnetic Resonance Imaging Study.

PubMed

Deng, Demao; Duan, Gaoxiong; Liao, Hai; Liu, Yanfei; Wang, Geliang; Liu, Huimei; Tang, Lijun; Pang, Yong; Tao, Jien; He, Xin; Yuan, Wenzhao; Liu, Peng

2016-10-01

According to the Traditional Chinese Medicine theory of acupuncture, Baihui (GV20) is applied to treat neurological and psychiatric disorders. However, the relationships between neural responses and GV20 remain unknown. Thus, the main aim of this study was to examine the brain responses induced by electro-acupuncture stimulation (EAS) at GV20. Functional magnetic resonance imaging (fMRI) was performed in 33 healthy subjects. Based on the non-repeated event-related (NRER) paradigm, group differences were examined between GV20 and a sham acupoint using the regional homogeneity (ReHo) method. Compared with the sham acupoint, EAS at GV20 induced increased ReHo in regions including the orbital frontal cortex (OFC), middle cingulate cortex (MCC), precentral cortex, and precuneus (preCUN). Decreased ReHo was found in the anterior cingulate cortex (ACC), supplementary motor area (SMA), thalamus, putamen, and cerebellum. The current findings provide preliminary neuroimaging evidence to indicate that EAS at GV20 could induce a specific pattern of neural responses by analysis of ReHo of brain activity. These findings might improve the understanding of mechanisms of acupuncture stimulation at GV20.

Creativity and the default network: A functional connectivity analysis of the creative brain at rest.

PubMed

Beaty, Roger E; Benedek, Mathias; Wilkins, Robin W; Jauk, Emanuel; Fink, Andreas; Silvia, Paul J; Hodges, Donald A; Koschutnig, Karl; Neubauer, Aljoscha C

2014-11-01

The present research used resting-state functional magnetic resonance imaging (fMRI) to examine whether the ability to generate creative ideas corresponds to differences in the intrinsic organization of functional networks in the brain. We examined the functional connectivity between regions commonly implicated in neuroimaging studies of divergent thinking, including the inferior prefrontal cortex and the core hubs of the default network. Participants were prescreened on a battery of divergent thinking tests and assigned to high- and low-creative groups based on task performance. Seed-based functional connectivity analysis revealed greater connectivity between the left inferior frontal gyrus (IFG) and the entire default mode network in the high-creative group. The right IFG also showed greater functional connectivity with bilateral inferior parietal cortex and the left dorsolateral prefrontal cortex in the high-creative group. The results suggest that the ability to generate creative ideas is characterized by increased functional connectivity between the inferior prefrontal cortex and the default network, pointing to a greater cooperation between brain regions associated with cognitive control and low-level imaginative processes. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Neural Bases of Language Switching in High and Early Proficient Bilinguals

ERIC Educational Resources Information Center

Garbin, G.; Costa, A.; Sanjuan, A.; Forn, C.; Rodriguez-Pujadas, A.; Ventura, N.; Belloch, V.; Hernandez, M.; Avila, C.

2011-01-01

The left inferior frontal cortex, the caudate and the anterior cingulate have been proposed as the neural origin of language switching, but most of the studies were conducted in low proficient bilinguals. In the present study, we investigated brain areas involved in language switching in a sample of 19 early, high-proficient Spanish-Catalan…

Brief Report: S6 Ribosomal Protein Phosphorylation in Autistic Frontal Cortex and Cerebellum: A Tissue Array Analysis

ERIC Educational Resources Information Center

Eberhart, Charles G.; Copeland, Joshua; Abel, Ty W.

2006-01-01

Few autistic brain samples are available for study, limiting investigations into molecular and histopathological abnormalities associated with this common disease. To facilitate distribution of samples, we have constructed a tissue array containing cerebral and cerebellar cores from 5 autistic children, 1 girl with Rett syndrome, and 5 age-matched…

Laterality and the evolution of the prefronto-cerebellar system in anthropoids.

PubMed

Smaers, Jeroen B; Steele, James; Case, Charleen R; Amunts, Katrin

2013-06-01

There is extensive evidence for an early vertebrate origin of lateralized motor behavior and of related asymmetries in underlying brain systems. We investigate human lateralized motor functioning in a broad comparative context of evolutionary neural reorganization. We quantify evolutionary trends in the fronto-cerebellar system (involved in motor learning) across 46 million years of divergent primate evolution by comparing rates of evolution of prefrontal cortex, frontal motor cortex, and posterior cerebellar hemispheres along individual branches of the primate tree of life. We provide a detailed evolutionary model of the neuroanatomical changes leading to modern human lateralized motor functioning, demonstrating an increased role for the fronto-cerebellar system in the apes dating to their evolutionary divergence from the monkeys (∼30 million years ago (Mya)), and a subsequent shift toward an increased role for prefrontal cortex over frontal motor cortex in the fronto-cerebellar system in the Homo-Pan ancestral lineage (∼10 Mya) and in the human ancestral lineage (∼6 Mya). We discuss these results in the context of cortico-cerebellar functions and their likely role in the evolution of human tool use and speech. © 2013 New York Academy of Sciences.

Decreased Regional Cortical Thickness and Thinning Rate Are Associated with Inattention Symptoms in Healthy Children

PubMed Central

Ducharme, Simon; Hudziak, James J.; Botteron, Kelly N.; Albaugh, Matthew D.; Nguyen, Tuong-Vi; Karama, Sherif; Evans, Alan C.

2011-01-01

Objective Children with attention-deficit/hyperactivity disorder (ADHD) have delayed cortical maturation, evidenced by regionally specific slower cortical thinning. However, the relationship between cortical maturation and attention capacities in typically developing children is unknown. This study examines cortical thickness correlates of inattention symptoms in a large sample of healthy children. Method Data from 357 healthy subjects (6.0–18.4 years of age) were obtained from the NIH MRI Study of Normal Brain Development. In cross-sectional analysis (first visit, n = 257), Child Behavior Checklist Attention Problems (AP) scores were linearly regressed against cortical thickness, controlling for age, gender, total brain volume, and site. For longitudinal data (up to three visits, n = 357/672 scans), similar analyses were performed using mixed-effects linear regressions. Interactions of AP with age and gender were tested. Results A cross-sectional “AP by age” interaction was found in bilateral orbito-frontal cortex, right inferior frontal cortex, bilateral ventromedial prefrontal cortex, bilateral dorsolateral prefrontal cortex, and several additional attention network regions. The interaction was due to negative associations between AP and thickness in younger subjects (6–10 years of age) that gradually disappeared over time secondary to slower cortical thinning. Similar trends were present in longitudinal analyses. Conclusions Higher AP scores were associated with thinner cortex at baseline and slower cortical thinning with aging in multiple areas involved in attention processes. Similar patterns have been identified in ADHD, suggesting a dimensional component to the link between attention and cortical maturation. The identified association between cortical maturation and attention in healthy development will help to inform studies of neuroimaging biomarkers of ADHD. PMID:22176936

Dopamine and μ-opioid receptor dysregulation in the brains of binge-eating female rats - possible relevance in the psychopathology and treatment of binge-eating disorder.

PubMed

Heal, David J; Hallam, Michelle; Prow, Michael; Gosden, Jane; Cheetham, Sharon; Choi, Yong K; Tarazi, Frank; Hutson, Peter

2017-06-01

Adult, female rats given irregular, limited access to chocolate develop binge-eating behaviour with normal bodyweight and compulsive/perseverative and impulsive behaviours similar to those in binge-eating disorder. We investigated whether (a) dysregulated central nervous system dopaminergic and opioidergic systems are part of the psychopathology of binge-eating and (b) these neurotransmitter systems may mediate the actions of drugs ameliorating binge-eating disorder psychopathology. Binge-eating produced a 39% reduction of striatal D 1 receptors with 22% and 23% reductions in medial and lateral caudate putamen and a 22% increase of striatal μ-opioid receptors. There was no change in D 1 receptor density in nucleus accumbens, medial prefrontal cortex or dorsolateral frontal cortex, striatal D 2 receptors and dopamine reuptake transporter sites, or μ-opioid receptors in frontal cortex. There were no changes in ligand affinities. The concentrations of monoamines, metabolites and estimates of dopamine (dopamine/dihydroxyphenylacetic acid ratio) and serotonin/5-hydroxyindolacetic acid ratio turnover rates were unchanged in striatum and frontal cortex. However, turnover of dopamine and serotonin in the hypothalamus was increased ~20% and ~15%, respectively. Striatal transmission via D 1 receptors is decreased in binge-eating rats while μ-opioid receptor signalling may be increased. These changes are consistent with the attenuation of binge-eating by lisdexamfetamine, which increases catecholaminergic neurotransmission, and nalmefene, a μ-opioid antagonist.

Intrinsic Brain Connectivity in Chronic Pain: A Resting-State fMRI Study in Patients with Rheumatoid Arthritis

PubMed Central

Flodin, Pär; Martinsen, Sofia; Altawil, Reem; Waldheim, Eva; Lampa, Jon; Kosek, Eva; Fransson, Peter

2016-01-01

Background: Rheumatoid arthritis (RA) is commonly accompanied by pain that is discordant with the degree of peripheral pathology. Very little is known about the cerebral processes involved in pain processing in RA. Here we investigated resting-state brain connectivity associated with prolonged pain in RA. Methods: 24 RA subjects and 19 matched controls were compared with regard to both behavioral measures of pain perception and resting-resting state fMRI data acquired subsequently to fMRI sessions involving pain stimuli. The resting-state fMRI brain connectivity was investigated using 159 seed regions located in cardinal pain processing brain regions. Additional principal component based multivariate pattern analysis of the whole brain connectivity pattern was carried out in a data driven analysis to localize group differences in functional connectivity. Results: When RA patients were compared to controls, we observed significantly lower pain resilience for pressure on the affected finger joints (i.e., P50-joint) and an overall heightened level of perceived global pain in RA patients. Relative to controls, RA patients displayed increased brain connectivity predominately for the supplementary motor areas, mid-cingulate cortex, and the primary sensorimotor cortex. Additionally, we observed an increase in brain connectivity between the insula and prefrontal cortex as well as between anterior cingulate cortex and occipital areas for RA patients. None of the group differences in brain connectivity were significantly correlated with behavioral parameters. Conclusion: Our study provides experimental evidence of increased connectivity between frontal midline regions that are implicated in affective pain processing and bilateral sensorimotor regions in RA patients. PMID:27014038

[Prosopagnosia and facial expression recognition].

PubMed

Koyama, Shinichi

2014-04-01

This paper reviews clinical neuropsychological studies that have indicated that the recognition of a person's identity and the recognition of facial expressions are processed by different cortical and subcortical areas of the brain. The fusiform gyrus, especially the right fusiform gyrus, plays an important role in the recognition of identity. The superior temporal sulcus, amygdala, and medial frontal cortex play important roles in facial-expression recognition. Both facial recognition and facial-expression recognition are highly intellectual processes that involve several regions of the brain.

Behavioural and brain responses related to Internet search and memory.

PubMed

Dong, Guangheng; Potenza, Marc N

2015-10-01

The ready availability of data via searches on the Internet has changed how many people seek and perhaps store and recall information, although the brain mechanisms underlying these processes are not well understood. This study investigated brain mechanisms underlying Internet-based vs. non-Internet-based searching. The results showed that Internet searching was associated with lower accuracy in recalling information as compared with traditional book searching. During functional magnetic resonance imaging, Internet searching was associated with less regional brain activation in the left ventral stream, the association area of the temporal-parietal-occipital cortices, and the middle frontal cortex. When comparing novel items with remembered trials, Internet-based searching was associated with higher brain activation in the right orbitofrontal cortex and lower brain activation in the right middle temporal gyrus when facing those novel trials. Brain activations in the middle temporal gyrus were inversely correlated with response times, and brain activations in the orbitofrontal cortex were positively correlated with self-reported search impulses. Taken together, the results suggest that, although Internet-based searching may have facilitated the information-acquisition process, this process may have been performed more hastily and be more prone to difficulties in recollection. In addition, people appear less confident in recalling information learned through Internet searching and that recent Internet searching may promote motivation to use the Internet. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

A longitudinal fMRI investigation in acute post-traumatic stress disorder (PTSD).

PubMed

Ke, Jun; Zhang, Li; Qi, Rongfeng; Li, Weihui; Hou, Cailan; Zhong, Yuan; He, Zhong; Li, Lingjiang; Lu, Guangming

2016-11-01

Background Neuroimaging studies have implicated limbic, paralimbic, and prefrontal cortex in the pathophysiology of chronic post-traumatic stress disorder (PTSD). However, little is known about the neural substrates of acute PTSD and how they change with symptom improvement. Purpose To examine the neural circuitry underlying acute PTSD and brain function changes during clinical recovery from this disorder. Material and Methods Nineteen acute PTSD patients and nine non-PTSD subjects who all experienced a devastating mining accident underwent clinical assessment as well as functional magnetic resonance imaging (fMRI) scanning while viewing trauma-related and neutral pictures. Two years after the accident, a subgroup of 17 patients completed a second clinical evaluation, of which 13 were given an identical follow-up scan. Results Acute PTSD patients demonstrated greater activation in the vermis and right posterior cingulate, and greater deactivation in the bilateral medial prefrontal cortex and inferior parietal lobules than controls in the traumatic versus neutral condition. At follow-up, PTSD patients showed symptom reduction and decreased activation in the right middle frontal gyrus, bilateral posterior cingulate/precuneus, and cerebellum. Correlation results confirmed these findings and indicated that brain activation in the posterior cingulate/precuneus and vermis was predictive of PTSD symptom improvement. Conclusion The findings support the involvement of the medial prefrontal cortex, inferior parietal lobule, posterior cingulate, and vermis in the pathogenesis of acute PTSD. Brain activation in the vermis and posterior cingulate/precuneus appears to be a biological marker of recovery potential from PTSD. Furthermore, decreased activation of the middle frontal gyrus, posterior cingulate/precuneus, and cerebellum may reflect symptom improvement.

Differential Brain Activation in Anorexia Nervosa to Fat and Thin Words During a Stroop Task

PubMed Central

Redgrave, Graham W.; Bakker, Arnold; Bello, Nicholas T.; Caffo, Brian S.; Coughlin, Janelle W.; Guarda, Angela S.; McEntee, Julie E.; Pekar, James J.; Reinblatt, Shauna P.; Verduzco, Guillermo; Moran, Timothy H.

2010-01-01

We measured brain activation in six anorexia nervosa patients and six healthy controls performing a novel emotional Stroop task using Fat, Thin, and Neutral words, and words made of XXXXs. Reaction times increased in the patient group in Thin and Fat conditions. In the Thin-XXXX contrast, patients showed greater activation than controls at the junction of left insula, frontal and temporal lobes and in left middle and medial frontal gyri. In the Fat-XXXX contrast, controls showed greater activation in left dorsolateral prefrontal cortex and right parietal areas. Mechanisms underlying attentional bias in anorexia nervosa likely differ under conditions of positive and negative valence. This paradigm is a promising tool to examine neural mediation of emotional response in anorexia nervosa. PMID:18628661

Brain activation during fast driving in a driving simulator: the role of the lateral prefrontal cortex.

PubMed

Jäncke, Lutz; Brunner, Béatrice; Esslen, Michaela

2008-07-16

Little is currently known about the neural underpinnings of the cognitive control of driving behavior in realistic situations and of the driver's speeding behavior in particular. In this study, participants drove in realistic scenarios presented in a high-end driving simulator. Scalp-recorded EEG oscillations in the alpha-band (8-13 Hz) with a 30-electrode montage were recorded while the participants drove under different conditions: (i) excessively fast (Fast), (ii) in a controlled manner at a safe speed (Correct), and (iii) impatiently in the context of testing traffic conditions (Impatient). Intracerebral sources of alpha-band activation were estimated using low resolution electrical tomography. Given that previous studies have shown a strong negative correlation between the Bold response in the frontal cortex and the alpha-band power, we used alpha-band-related activity as an estimation of frontal activation. Statistical analysis revealed more alpha-band-related activity (i.e. less neuronal activation) in the right lateral prefrontal cortex, including the dorsolateral prefrontal cortex, during fast driving. Those participants who speeded most and exhibited greater risk-taking behavior demonstrated stronger alpha-related activity (i.e. less neuronal activation) in the left anterior lateral prefrontal cortex. These findings are discussed in the context of current theories about the role of the lateral prefrontal cortex in controlling risk-taking behavior, task switching, and multitasking.

Effects of maternal separation, early handling, and gonadal sex on regional metabolic capacity of the preweanling rat brain

PubMed Central

Spivey, Jaclyn M.; Padilla, Eimeira; Shumake, Jason D.; Gonzalez-Lima, F.

2010-01-01

This is the first study to assess the effects of mother-infant separation on regional metabolic capacity in the preweanling rat brain. Mother-infant separation is generally known to be stressful for rat pups. Holtzman adolescent rats show a depressive-like behavioral phenotype after maternal separation during the preweanling period. However, information is lacking on the effects of maternal separation on the brains of rat pups. We addressed this issue by mapping the brains of preweanling Holtzman rat pups using cytochrome oxidase histochemistry, which reflects long-term changes in brain metabolic capacity, following two weeks of repeated, prolonged maternal separation, and compared this to both early handled and non-handled pups. Quantitative image analysis revealed that maternal separation reduced cytochrome oxidase activity in the medial prefrontal cortex and nucleus accumbens shell. Maternal separation reduced prefrontal cytochrome oxidase to a greater degree in female pups than in males. Early handling reduced cytochrome oxidase activity in the posterior parietal cortex, ventral tegmental area, and subiculum, but increased cytochrome oxidase activity in the lateral frontal cortex. The sex-dependent effects of early handling on cytochrome oxidase activity were limited to the medial prefrontal cortex. Regardless of separation group, females had greater cytochrome oxidase activity in the habenula and ventral tegmental area compared to males. These findings suggest that early life mother-infant separation results in dysfunction of prefrontal and mesolimbic regions in the preweanling rat brain that may contribute to behavioral changes later in life. PMID:20969837

Frontal Lobe Contusion in Mice Chronically Impairs Prefrontal-Dependent Behavior

PubMed Central

Rosi, Susanna

2016-01-01

Traumatic brain injury (TBI) is a major cause of chronic disability in the world. Moderate to severe TBI often results in damage to the frontal lobe region and leads to cognitive, emotional, and social behavioral sequelae that negatively affect quality of life. More specifically, TBI patients often develop persistent deficits in social behavior, anxiety, and executive functions such as attention, mental flexibility, and task switching. These deficits are intrinsically associated with prefrontal cortex (PFC) functionality. Currently, there is a lack of analogous, behaviorally characterized TBI models for investigating frontal lobe injuries despite the prevalence of focal contusions to the frontal lobe in TBI patients. We used the controlled cortical impact (CCI) model in mice to generate a frontal lobe contusion and studied behavioral changes associated with PFC function. We found that unilateral frontal lobe contusion in mice produced long-term impairments to social recognition and reversal learning while having only a minor effect on anxiety and completely sparing rule shifting and hippocampal-dependent behavior. PMID:26964036

Network modulation during complex syntactic processing

PubMed Central

den Ouden, Dirk-Bart; Saur, Dorothee; Mader, Wolfgang; Schelter, Björn; Lukic, Sladjana; Wali, Eisha; Timmer, Jens; Thompson, Cynthia K.

2011-01-01

Complex sentence processing is supported by a left-lateralized neural network including inferior frontal cortex and posterior superior temporal cortex. This study investigates the pattern of connectivity and information flow within this network. We used fMRI BOLD data derived from 12 healthy participants reported in an earlier study (Thompson, C. K., Den Ouden, D. B., Bonakdarpour, B., Garibaldi, K., & Parrish, T. B. (2010b). Neural plasticity and treatment-induced recovery of sentence processing in agrammatism. Neuropsychologia, 48(11), 3211-3227) to identify activation peaks associated with object-cleft over syntactically less complex subject-cleft processing. Directed Partial Correlation Analysis was conducted on time series extracted from participant-specific activation peaks and showed evidence of functional connectivity between four regions, linearly between premotor cortex, inferior frontal gyrus, posterior superior temporal sulcus and anterior middle temporal gyrus. This pattern served as the basis for Dynamic Causal Modeling of networks with a driving input to posterior superior temporal cortex, which likely supports thematic role assignment, and networks with a driving input to inferior frontal cortex, a core region associated with syntactic computation. The optimal model was determined through both frequentist and Bayesian model selection and turned out to reflect a network with a primary drive from inferior frontal cortex and modulation of the connection between inferior frontal and posterior superior temporal cortex by complex sentence processing. The winning model also showed a substantive role for a feedback mechanism from posterior superior temporal cortex back to inferior frontal cortex. We suggest that complex syntactic processing is driven by word-order analysis, supported by inferior frontal cortex, in an interactive relation with posterior superior temporal cortex, which supports verb argument structure processing. PMID:21820518

Causality within the Epileptic Network: An EEG-fMRI Study Validated by Intracranial EEG.

PubMed

Vaudano, Anna Elisabetta; Avanzini, Pietro; Tassi, Laura; Ruggieri, Andrea; Cantalupo, Gaetano; Benuzzi, Francesca; Nichelli, Paolo; Lemieux, Louis; Meletti, Stefano

2013-01-01

Accurate localization of the Seizure Onset Zone (SOZ) is crucial in patients with drug-resistance focal epilepsy. EEG with fMRI recording (EEG-fMRI) has been proposed as a complementary non-invasive tool, which can give useful additional information in the pre-surgical work-up. However, fMRI maps related to interictal epileptiform activities (IED) often show multiple regions of signal change, or "networks," rather than highly focal ones. Effective connectivity approaches like Dynamic Causal Modeling (DCM) applied to fMRI data potentially offers a framework to address which brain regions drives the generation of seizures and IED within an epileptic network. Here, we present a first attempt to validate DCM on EEG-fMRI data in one patient affected by frontal lobe epilepsy. Pre-surgical EEG-fMRI demonstrated two distinct clusters of blood oxygenation level dependent (BOLD) signal increases linked to IED, one located in the left frontal pole and the other in the ipsilateral dorso-lateral frontal cortex. DCM of the IED-related BOLD signal favored a model corresponding to the left dorso-lateral frontal cortex as driver of changes in the fronto-polar region. The validity of DCM was supported by: (a) the results of two different non-invasive analysis obtained on the same dataset: EEG source imaging (ESI), and "psycho-physiological interaction" analysis; (b) the failure of a first surgical intervention limited to the fronto-polar region; (c) the results of the intracranial EEG monitoring performed after the first surgical intervention confirming a SOZ located over the dorso-lateral frontal cortex. These results add evidence that EEG-fMRI together with advanced methods of BOLD signal analysis is a promising tool that can give relevant information within the epilepsy surgery diagnostic work-up.

Autoradiographic distribution of 5-HT7 receptors in the human brain using [3H]mesulergine: comparison to other mammalian species

PubMed Central

Martín-Cora, Francisco J; Pazos, Angel

2003-01-01

The main aim of this investigation was to delineate the distribution of the 5-HT7 receptor in human brain. Autoradiographic studies in guinea-pig and rat brain were also carried out in order to revisit and compare the anatomical distribution of 5-HT7 receptors in different mammalian species.Binding studies were performed in rat frontal cortex membranes using 10 nM [3H]mesulergine in the presence of raclopride (10 μM) and DOI (0.8 μM). Under these conditions, a binding site with pharmacological characteristics consistent with those of the 5-HT7 receptors was identified (rank order of binding affinity values: 5-CT>5-HT>5-MeOT>mesulergine ≈methiothepin>8-OH-DPAT=spiperone ≈(+)-butaclamol≫imipramine ≈(±)-pindolol≫ondansetron ≈clonidine ≈prazosin).The autoradiographic studies revealed that the anatomical distribution of 5-HT7 receptors throughout the human brain was heterogenous. High densities were found over the caudate and putamen nuclei, the pyramidal layer of the CA2 field of the hippocampus, the centromedial thalamic nucleus, and the dorsal raphe nucleus. The inner layer of the frontal cortex, the dentate gyrus of the hippocampus, the subthalamic nucleus and superior colliculus, among others, presented intermediate concentrations of 5-HT7 receptors. A similar brain anatomical distribution of 5-HT7 receptors was observed in all three mammalian species studied.By using [3H]mesulergine, we have mapped for the first time the anatomical distribution of 5-HT7 receptors in the human brain, overcoming the limitations previously found in radiometric studies with other radioligands, and also revisiting the distribution in guinea-pig and rat brain. PMID:14656806

Cognitive control of drug craving inhibits brain reward regions in cocaine abusers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Volkow, N.D.; Fowler, J.; Wang, G.J.

Loss of control over drug taking is considered a hallmark of addiction and is critical in relapse. Dysfunction of frontal brain regions involved with inhibitory control may underlie this behavior. We evaluated whether addicted subjects when instructed to purposefully control their craving responses to drug-conditioned stimuli can inhibit limbic brain regions implicated in drug craving. We used PET and 2-deoxy-2[18F]fluoro-D-glucose to measure brain glucose metabolism (marker of brain function) in 24 cocaine abusers who watched a cocaine-cue video and compared brain activation with and without instructions to cognitively inhibit craving. A third scan was obtained at baseline (without video). Statisticalmore » parametric mapping was used for analysis and corroborated with regions of interest. The cocaine-cue video increased craving during the no-inhibition condition (pre 3 {+-} 3, post 6 {+-} 3; p < 0.001) but not when subjects were instructed to inhibit craving (pre 3 {+-} 2, post 3 {+-} 3). Comparisons with baseline showed visual activation for both cocaine-cue conditions and limbic inhibition (accumbens, orbitofrontal, insula, cingulate) when subjects purposefully inhibited craving (p < 0.001). Comparison between cocaine-cue conditions showed lower metabolism with cognitive inhibition in right orbitofrontal cortex and right accumbens (p < 0.005), which was associated with right inferior frontal activation (r = -0.62, p < 0.005). Decreases in metabolism in brain regions that process the predictive (nucleus accumbens) and motivational value (orbitofrontal cortex) of drug-conditioned stimuli were elicited by instruction to inhibit cue-induced craving. This suggests that cocaine abusers may retain some ability to inhibit craving and that strengthening fronto-accumbal regulation may be therapeutically beneficial in addiction.« less

[Changes of brain pain center and default mode network an electro acupuncture in Weizhong and Dachangshu acupoints: a task-fMRI study].

PubMed

Zhou, S; Cao, H X; Yu, L C; Jin, Y J; Jia, R H; Wen, Y R; Chen, X F

2016-02-23

To investigate the functional brain pain center and default mode network response to electro acupuncture stimulate in weizhong acupoints(BL40) and dachangshu acupoints(BL25). During January to February 2015, volunteers were enrolled in this study from the staff and student interns of Gansu Province Traditional Chinese Medicine Hospital. A total of 20 healthy, right-handed subjects, male 9, female 11, age (23±3) years, participated in this study. Block design task functional magnetic resonance imaging(fMRI) 3.0 T was performed in all subjects by electro acupuncture stimulating at BL40 and BL25 from the same experienced acupuncturist.The needle connected electric acupuncture apparatus through tow long coaxial-cable. A block design with five 120 s blocks of rest time (OFF block, electric acupuncture turn off ) interspersed between five 60 s blocks of stimulation (ON block, electric acupuncture turn on) fMRI scan. Magnetic resonance data of brain function was collected and FSL(fMRI Software Library) software was used to analyze the data. All subjects' data were analyzed except 2 cases whose head movement were more than 2 mm. Activated brain function regions by electro acupuncture stimulate included temporal lobe lateral sulcus, lobus insularis, thalamus, supramarginal gyrus, prefrontal medial frontal gyrus. Negative activated brain regions included middle frontal gyrus, parahippocampal gyrus, cingulate cortex abdominal segment, parietal cortex.The functional pain central and default mode network were changed when electro acupuncture stimulate in(BL40) and(BL25). There are several brain activation regions and negative activated brain regions when administering electro acupuncture stimulation at BL40 and BL25.

Brain reward system's alterations in response to food and monetary stimuli in overweight and obese individuals.

PubMed

Verdejo-Román, Juan; Vilar-López, Raquel; Navas, Juan F; Soriano-Mas, Carles; Verdejo-García, Antonio

2017-02-01

The brain's reward system is crucial to understand obesity in modern society, as increased neural responsivity to reward can fuel the unhealthy food choices that are driving the growing obesity epidemic. Brain's reward system responsivity to food and monetary rewards in individuals with excessive weight (overweight and obese) versus normal weight controls, along with the relationship between this responsivity and body mass index (BMI) were tested. The sample comprised 21 adults with obesity (BMI > 30), 21 with overweight (BMI between 25 and 30), and 39 with normal weight (BMI < 25). Participants underwent a functional magnetic resonance imaging (fMRI) session while performing two tasks that involve the processing of food (Willing to Pay) and monetary rewards (Monetary Incentive Delay). Neural activations within the brain reward system were compared across the three groups. Curve fit analyses were conducted to establish the association between BMI and brain reward system's response. Individuals with obesity had greater food-evoked responsivity in the dorsal and ventral striatum compared with overweight and normal weight groups. There was an inverted U-shape association between BMI and monetary-evoked responsivity in the ventral striatum, medial frontal cortex, and amygdala; that is, individuals with BMIs between 27 and 32 had greater responsivity to monetary stimuli. Obesity is associated with greater food-evoked responsivity in the ventral and dorsal striatum, and overweight is associated with greater monetary-evoked responsivity in the ventral striatum, the amygdala, and the medial frontal cortex. Findings suggest differential reactivity of the brain's reward system to food versus monetary rewards in obesity and overweight. Hum Brain Mapp 38:666-677, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Aged rats are more vulnerable than adolescents to "ecstasy"-induced toxicity.

PubMed

Feio-Azevedo, R; Costa, V M; Barbosa, D J; Teixeira-Gomes, A; Pita, I; Gomes, S; Pereira, F C; Duarte-Araújo, M; Duarte, J A; Marques, F; Fernandes, E; Bastos, M L; Carvalho, F; Capela, J P

2018-06-04

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") is a widespread drug of abuse with known neurotoxic properties. The present study aimed to evaluate the differential toxic effects of MDMA in adolescent and aged Wistar rats, using doses pharmacologically comparable to humans. Adolescent (post-natal day 40) (3 × 5 mg/kg, 2 h apart) and aged (mean 20 months old) (2 × 5 mg/kg, 2 h apart) rats received MDMA intraperitoneally. Animals were killed 7 days later, and the frontal cortex, hippocampus, striatum and cerebellum brain areas were dissected, and heart, liver and kidneys were collected. MDMA caused hyperthermia in both treated groups, but aged rats had a more dramatic temperature elevation. MDMA promoted serotonergic neurotoxicity only in the hippocampus of aged, but not in the adolescents' brain, and did not change the levels of dopamine or serotonin metabolite in the striatum of both groups. Differential responses according to age were also seen regarding brain p-Tau levels, a hallmark of a degenerative brain, since only aged animals had significant increases. MDMA evoked brain oxidative stress in the hippocampus and striatum of aged, and in the hippocampus, frontal cortex, and striatum brain areas of adolescents according to protein carbonylation, but only decreased GSH levels in the hippocampus of aged animals. The brain maturational stage seems crucial for MDMA-evoked serotonergic neurotoxicity. Aged animals were more susceptible to MDMA-induced tissue damage in the heart and kidneys, and both ages had an increase in liver fibrotic tissue content. In conclusion, age is a determinant factor for the toxic events promoted by "ecstasy". This work demonstrated special susceptibility of aged hippocampus to MDMA neurotoxicity, as well as impressive damage to the heart and kidney tissue following "ecstasy".

Influence of 4-week multi-strain probiotic administration on resting-state functional connectivity in healthy volunteers.

PubMed

Bagga, Deepika; Aigner, Christoph Stefan; Reichert, Johanna Louise; Cecchetto, Cinzia; Fischmeister, Florian Ph S; Holzer, Peter; Moissl-Eichinger, Christine; Schöpf, Veronika

2018-05-30

Experimental investigations in rodents have contributed significantly to our current understanding of the potential importance of the gut microbiome and brain interactions for neurotransmitter expression, neurodevelopment, and behaviour. However, clinical evidence to support such interactions is still scarce. The present study used a double-blind, randomized, pre- and post-intervention assessment design to investigate the effects of a 4-week multi-strain probiotic administration on whole-brain functional and structural connectivity in healthy volunteers. Forty-five healthy volunteers were recruited for this study and were divided equally into three groups (PRP: probiotic, PLP: placebo, and CON: control). All the participants underwent resting-state functional MRI and diffusion MRI brain scans twice during the course of study, at the beginning (time point 1) and after 4 weeks (time point 2). MRI data were acquired using a 3T whole-body MR system (Magnetom Skyra, Siemens, Germany). Functional connectivity (FC) changes were observed in the default mode network (DMN), salience network (SN), and middle and superior frontal gyrus network (MFGN) in the PRP group as compared to the PLP and CON groups. PRP group showed a significant decrease in FC in MFGN (in frontal pole and frontal medial cortex) and in DMN (in frontal lobe) as compared to CON and PLP groups, respectively. Further, significant increase in FC in SN (in cingulate gyrus and precuneus cortex) was also observed in PRP group as compared to CON group. The significance threshold was set to p < 0.05 FWE corrected. No significant structural differences were observed between the three groups. This work provides new insights into the role of a multi-strain probiotic administration in modulating the behaviour, which is reflected as changes in the FC in healthy volunteers. This study motivates future investigations into the role of probiotics in context of major depression and stress disorders.

Frontal Gamma-Aminobutyric Acid Concentrations Are Associated With Cognitive Performance in Older Adults

PubMed Central

Porges, Eric C.; Woods, Adam J.; Edden, Richard A.E.; Puts, Nicolaas A.J.; Harris, Ashley D.; Chen, Huaihou; Garcia, Amanda M.; Seider, Talia R.; Lamb, Damon G.; Williamson, John B.; Cohen, Ronald A.

2017-01-01

BACKGROUND Gamma-aminobutyric acid (GABA), the brain’s principal inhibitory neurotransmitter, has been associated with perceptual and attentional functioning. Recent application of magnetic resonance spectroscopy (MRS) provides in vivo evidence for decreasing GABA concentrations during adulthood. It is unclear, however, how age-related decrements in cerebral GABA concentrations contribute to cognitive decline, or whether previously reported declines in cerebral GABA concentrations persist during healthy aging. We hypothesized that participants with higher GABA concentrations in the frontal cortex would exhibit superior cognitive function and that previously reported age-related decreases in cortical GABA concentrations continue into old age. METHODS We measured GABA concentrations in frontal and posterior midline cerebral regions using a Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) 1H-MRS approach in 94 older adults without history or clinical evidence of mild cognitive impairment or dementia (mean age, 73 years). We administered the Montreal Cognitive Assessment to assess cognitive functioning. RESULTS Greater frontal GABA concentrations were associated with superior cognitive performance. This relation remained significant after controlling for age, years of education, and brain atrophy. GABA concentrations in both frontal and posterior regions decreased as a function of age. CONCLUSIONS These novel findings from a large, healthy, older population indicate that cognitive function is sensitive to cerebral GABA concentrations in the frontal cortex, and GABA concentration in frontal and posterior regions continue to decline in later age. These effects suggest that proton MRS may provide a clinically useful method for the assessment of normal and abnormal age-related cognitive changes and the associated physiological contributors. PMID:28217759

SPATIAL NEGLECT AND ATTENTION NETWORKS

PubMed Central

Corbetta, Maurizio; Shulman, Gordon L.

2013-01-01

Unilateral spatial neglect is a common neurological syndrome following predominantly right hemisphere injuries to ventral fronto-parietal cortex. We propose that neglect reflects deficits in the coding of saliency, control of spatial attention, and representation within an egocentric frame of reference, in conjunction with non-spatial deficits of reorienting, target detection, and arousal/vigilance. In contrast to theories that link spatial neglect to structural damage of specific brain regions, we argue that neglect is better explained by the physiological dysfunction of distributed cortical networks. The ventral lesions in right parietal, temporal, and frontal cortex that cause neglect directly impair non-spatial functions and hypoactivate the right hemisphere, inducing abnormalities in task-evoked activity and functional connectivity of a dorsal frontal-parietal network that controls spatial attention. The anatomy and right hemisphere dominance of neglect follows from the anatomy and laterality of the ventral regions that interact with the dorsal attention network. PMID:21692662

Dorso-Lateral Prefrontal Cortex MRI Measurements and Cognitive Performance in Autism

PubMed Central

Griebling, Jessica; Minshew, Nancy J.; Bodner, Kimberly; Libove, Robin; Bansal, Rahul; Konasale, Prasad; Keshavan, Matcheri S.; Hardan, Antonio

2012-01-01

This study examined the relationships between volumetric measurements of frontal lobe structures and performance on executive function tasks in individuals with autism. MRI scans were obtained from 38 individuals with autism and 40 matched controls between the ages of 8 and 45 years. Executive function was assessed using neuropsychological measures including the Wisconsin Card Sorting Test and Tower of Hanoi. Differences in performance on the neuropsychological tests were found between the two groups. However, no differences in dorsolateral prefrontal cortex volumes were observed between groups. No correlations between volumetric measurements and performance on the neuropsychological tests were found. Findings from this study suggest that executive function deficits observed in autism are related to functional but not anatomical abnormalities of the frontal lobe. The absence of correlations suggests that executive dysfunction is not the result of focal brain alterations but, rather, is the result of a distributed neural network dysfunction. PMID:20097663

The Roles of Orbital Frontal Cortex in the Modulation of Antisocial Behavior

ERIC Educational Resources Information Center

Blair, R. J. R.

2004-01-01

This article considers potential roles of orbital frontal cortex in the modulation of antisocial behavior. Two forms of aggression are distinguished: reactive aggression elicited in response to frustration/threat and goal directed, instrumental aggression. It is suggested that orbital frontal cortex is directly involved in the modulation of…

The effects of physical activity on functional MRI activation associated with cognitive control in children: a randomized controlled intervention

PubMed Central

Chaddock-Heyman, Laura; Erickson, Kirk I.; Voss, Michelle W.; Knecht, Anya M.; Pontifex, Matthew B.; Castelli, Darla M.; Hillman, Charles H.; Kramer, Arthur F.

2013-01-01

This study used functional magnetic resonance imaging (fMRI) to examine the influence of a 9-month physical activity program on task-evoked brain activation during childhood. The results demonstrated that 8- to 9-year-old children who participated in 60+ min of physical activity, 5 days per week, for 9 months, showed decreases in fMRI brain activation in the right anterior prefrontal cortex coupled with within-group improvements in performance on a task of attentional and interference control. Children assigned to a wait-list control group did not show changes in brain function. Furthermore, at post-test, children in the physical activity group showed similar anterior frontal brain patterns and incongruent accuracy rates to a group of college-aged young adults. Children in the wait-list control group still differed from the young adults in terms of anterior prefrontal activation and performance at post-test. There were no significant changes in fMRI activation in the anterior cingulate cortex (ACC) for either group. These results suggest that physical activity during childhood may enhance specific elements of prefrontal cortex function involved in cognitive control. PMID:23487583

Clinical symptoms and alpha band resting-state functional connectivity imaging in patients with schizophrenia: implications for novel approaches to treatment

PubMed Central

Hinkley, Leighton B.N.; Vinogradov, Sophia; Guggisberg, Adrian G.; Fisher, Melissa; Findlay, Anne M.; Nagarajan, Srikantan S.

2011-01-01

Background Schizophrenia is associated with functional decoupling between cortical regions, but we do not know whether and where this occurs in low-frequency electromagnetic oscillations. The goal of this study was to use magnetoencephalography (MEG) to identify brain regions that exhibit abnormal resting-state connectivity in the alpha frequency range in patients with schizophrenia and investigate associations between functional connectivity and clinical symptoms in stable outpatient participants. Method Thirty patients with schizophrenia and fifteen healthy comparison participants were scanned in resting-state MEG (eyes closed). Functional connectivity MEGI (fcMEGI) data were reconstructed globally in the alpha range, quantified by the mean imaginary coherence between a voxel and the rest of the brain. Results In patients, decreased connectivity was observed in left pre-frontal cortex (PFC) and right superior temporal cortex while increased connectivity was observed in left extrastriate cortex and the right inferior PFC. Functional connectivity of left inferior parietal cortex was negatively related to positive symptoms. Low left PFC connectivity was associated with negative symptoms. Functional connectivity of midline PFC was negatively correlated with depressed symptoms. Functional connectivity of right PFC was associated with other (cognitive) symptoms. Conclusions This study demonstrates direct functional disconnection in schizophrenia between specific cortical fields within low-frequency resting-state oscillations. Impaired alpha coupling in frontal, parietal, and temporal regions is associated with clinical symptoms in these stable outpatients. Our findings indicate that this level of functional disconnection between cortical regions is an important treatment target in schizophrenia. PMID:21861988

Effect of visual experience on structural organization of the human brain: a voxel based morphometric study using DARTEL.

PubMed

Modi, Shilpi; Bhattacharya, Manisha; Singh, Namita; Tripathi, Rajendra Prasad; Khushu, Subash

2012-10-01

To investigate structural reorganization in the brain with differential visual experience using Voxel-Based Morphometry with Diffeomorphic Anatomic Registration Through Exponentiated Lie algebra algorithm (DARTEL) approach. High resolution structural MR images were taken in fifteen normal sighted healthy controls, thirteen totally blind subjects and six partial blind subjects. The analysis was carried out using SPM8 software on MATLAB 7.6.0 platform. VBM study revealed gray matter volume atrophy in the cerebellum and left inferior parietal cortex in total blind subjects and in left inferior parietal cortex, right caudate nucleus, and left primary visual cortex in partial blind subjects as compared to controls. White matter volume loss was found in calcarine gyrus in total blind subjects and Thlamus-somatosensory region in partially blind subjects as compared to controls. Besides, an increase in Gray Matter volume was also found in left middle occipital and middle frontal gyrus and right entorhinal cortex, and an increase in White Matter volume was found in superior frontal gyrus, left middle temporal gyrus and right Heschl's gyrus in totally blind subjects as compared to controls. Comparison between total and partial blind subjects revealed a greater Gray Matter volume in left cerebellum of partial blinds and left Brodmann area 18 of total blind subjects. Results suggest that, loss of vision at an early age can induce significant structural reorganization on account of the loss of visual input. These plastic changes are different in early onset of total blindness as compared to partial blindness. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A Combined Metabonomic and Proteomic Approach Identifies Frontal Cortex Changes in a Chronic Phencyclidine Rat Model in Relation to Human Schizophrenia Brain Pathology

PubMed Central

Wesseling, Hendrik; Chan, Man K; Tsang, T M; Ernst, Agnes; Peters, Fabian; Guest, Paul C; Holmes, Elaine; Bahn, Sabine

2013-01-01

Current schizophrenia (SCZ) treatments fail to treat the broad range of manifestations associated with this devastating disorder. Thus, new translational models that reproduce the core pathological features are urgently needed to facilitate novel drug discovery efforts. Here, we report findings from the first comprehensive label-free liquid-mass spectrometry proteomic- and proton nuclear magnetic resonance-based metabonomic profiling of the rat frontal cortex after chronic phencyclidine (PCP) intervention, which induces SCZ-like symptoms. The findings were compared with results from a proteomic profiling of post-mortem prefrontal cortex from SCZ patients and with relevant findings in the literature. Through this approach, we identified proteomic alterations in glutamate-mediated Ca2+ signaling (Ca2+/calmodulin-dependent protein kinase II, PPP3CA, and VISL1), mitochondrial function (GOT2 and PKLR), and cytoskeletal remodeling (ARP3). Metabonomic profiling revealed changes in the levels of glutamate, glutamine, glycine, pyruvate, and the Ca2+ regulator taurine. Effects on similar pathways were also identified in the prefrontal cortex tissue from human SCZ subjects. The discovery of similar but not identical proteomic and metabonomic alterations in the chronic PCP rat model and human brain indicates that this model recapitulates only some of the molecular alterations of the disease. This knowledge may be helpful in understanding mechanisms underlying psychosis, which, in turn, can facilitate improved therapy and drug discovery for SCZ and other psychiatric diseases. Most importantly, these molecular findings suggest that the combined use of multiple models may be required for more effective translation to studies of human SCZ. PMID:23942359