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Sample records for auditory brain regions

  1. Brain Region-Specific Activity Patterns after Recent or Remote Memory Retrieval of Auditory Conditioned Fear

    ERIC Educational Resources Information Center

    Kwon, Jeong-Tae; Jhang, Jinho; Kim, Hyung-Su; Lee, Sujin; Han, Jin-Hee

    2012-01-01

    Memory is thought to be sparsely encoded throughout multiple brain regions forming unique memory trace. Although evidence has established that the amygdala is a key brain site for memory storage and retrieval of auditory conditioned fear memory, it remains elusive whether the auditory brain regions may be involved in fear memory storage or…

  2. Quantitative map of multiple auditory cortical regions with a stereotaxic fine-scale atlas of the mouse brain

    PubMed Central

    Tsukano, Hiroaki; Horie, Masao; Hishida, Ryuichi; Takahashi, Kuniyuki; Takebayashi, Hirohide; Shibuki, Katsuei

    2016-01-01

    Optical imaging studies have recently revealed the presence of multiple auditory cortical regions in the mouse brain. We have previously demonstrated, using flavoprotein fluorescence imaging, at least six regions in the mouse auditory cortex, including the anterior auditory field (AAF), primary auditory cortex (AI), the secondary auditory field (AII), dorsoanterior field (DA), dorsomedial field (DM), and dorsoposterior field (DP). While multiple regions in the visual cortex and somatosensory cortex have been annotated and consolidated in recent brain atlases, the multiple auditory cortical regions have not yet been presented from a coronal view. In the current study, we obtained regional coordinates of the six auditory cortical regions of the C57BL/6 mouse brain and illustrated these regions on template coronal brain slices. These results should reinforce the existing mouse brain atlases and support future studies in the auditory cortex. PMID:26924462

  3. Brain region-specific activity patterns after recent or remote memory retrieval of auditory conditioned fear.

    PubMed

    Kwon, Jeong-Tae; Jhang, Jinho; Kim, Hyung-Su; Lee, Sujin; Han, Jin-Hee

    2012-01-01

    Memory is thought to be sparsely encoded throughout multiple brain regions forming unique memory trace. Although evidence has established that the amygdala is a key brain site for memory storage and retrieval of auditory conditioned fear memory, it remains elusive whether the auditory brain regions may be involved in fear memory storage or retrieval. To investigate this possibility, we systematically imaged the brain activity patterns in the lateral amygdala, MGm/PIN, and AuV/TeA using activity-dependent induction of immediate early gene zif268 after recent and remote memory retrieval of auditory conditioned fear. Consistent with the critical role of the amygdala in fear memory, the zif268 activity in the lateral amygdala was significantly increased after both recent and remote memory retrieval. Interesting, however, the density of zif268 (+) neurons in both MGm/PIN and AuV/TeA, particularly in layers IV and VI, was increased only after remote but not recent fear memory retrieval compared to control groups. Further analysis of zif268 signals in AuV/TeA revealed that conditioned tone induced stronger zif268 induction compared to familiar tone in each individual zif268 (+) neuron after recent memory retrieval. Taken together, our results support that the lateral amygdala is a key brain site for permanent fear memory storage and suggest that MGm/PIN and AuV/TeA might play a role for remote memory storage or retrieval of auditory conditioned fear, or, alternatively, that these auditory brain regions might have a different way of processing for familiar or conditioned tone information at recent and remote time phases. PMID:22993170

  4. Auditory motion in the sighted and blind: Early visual deprivation triggers a large-scale imbalance between auditory and "visual" brain regions.

    PubMed

    Dormal, Giulia; Rezk, Mohamed; Yakobov, Esther; Lepore, Franco; Collignon, Olivier

    2016-07-01

    How early blindness reorganizes the brain circuitry that supports auditory motion processing remains controversial. We used fMRI to characterize brain responses to in-depth, laterally moving, and static sounds in early blind and sighted individuals. Whole-brain univariate analyses revealed that the right posterior middle temporal gyrus and superior occipital gyrus selectively responded to both in-depth and laterally moving sounds only in the blind. These regions overlapped with regions selective for visual motion (hMT+/V5 and V3A) that were independently localized in the sighted. In the early blind, the right planum temporale showed enhanced functional connectivity with right occipito-temporal regions during auditory motion processing and a concomitant reduced functional connectivity with parietal and frontal regions. Whole-brain searchlight multivariate analyses demonstrated higher auditory motion decoding in the right posterior middle temporal gyrus in the blind compared to the sighted, while decoding accuracy was enhanced in the auditory cortex bilaterally in the sighted compared to the blind. Analyses targeting individually defined visual area hMT+/V5 however indicated that auditory motion information could be reliably decoded within this area even in the sighted group. Taken together, the present findings demonstrate that early visual deprivation triggers a large-scale imbalance between auditory and "visual" brain regions that typically support the processing of motion information. PMID:27107468

  5. Auditory evoked responses in musicians during passive vowel listening are modulated by functional connectivity between bilateral auditory-related brain regions.

    PubMed

    Kühnis, Jürg; Elmer, Stefan; Jäncke, Lutz

    2014-12-01

    Currently, there is striking evidence showing that professional musical training can substantially alter the response properties of auditory-related cortical fields. Such plastic changes have previously been shown not only to abet the processing of musical sounds, but likewise spectral and temporal aspects of speech. Therefore, here we used the EEG technique and measured a sample of musicians and nonmusicians while the participants were passively exposed to artificial vowels in the context of an oddball paradigm. Thereby, we evaluated whether increased intracerebral functional connectivity between bilateral auditory-related brain regions may promote sensory specialization in musicians, as reflected by altered cortical N1 and P2 responses. This assumption builds on the reasoning that sensory specialization is dependent, at least in part, on the amount of synchronization between the two auditory-related cortices. Results clearly revealed that auditory-evoked N1 responses were shaped by musical expertise. In addition, in line with our reasoning musicians showed an overall increased intracerebral functional connectivity (as indexed by lagged phase synchronization) in theta, alpha, and beta bands. Finally, within-group correlative analyses indicated a relationship between intracerebral beta band connectivity and cortical N1 responses, however only within the musicians' group. Taken together, we provide first electrophysiological evidence for a relationship between musical expertise, auditory-evoked brain responses, and intracerebral functional connectivity among auditory-related brain regions. PMID:24893742

  6. Research of brain activation regions of "yes" and "no" responses by auditory stimulations in human EEG

    NASA Astrophysics Data System (ADS)

    Hu, Min; Liu, GuoZhong

    2011-11-01

    People with neuromuscular disorders are difficult to communicate with the outside world. It is very important to the clinician and the patient's family that how to distinguish vegetative state (VS) and minimally conscious state (MCS) for a disorders of consciousness (DOC) patient. If a patient is diagnosed with VS, this means that the hope of recovery is greatly reduced, thus leading to the family to abandon the treatment. Brain-computer interface (BCI) is aiming to help those people by analyzing patients' electroencephalogram (EEG). This paper focus on analyzing the corresponding activated regions of the brain when a subject responses "yes" or "no" to an auditory stimuli question. When the brain concentrates, the phase of the related area will become orderly from desultorily. So in this paper we analyzed EEG from the angle of phase. Seven healthy subjects volunteered to participate in the experiment. A total of 84 groups of repeatability stimulation test were done. Firstly, the frequency is fragmented by using wavelet method. Secondly, the phase of EEG is extracted by Hilbert. At last, we obtained approximate entropy and information entropy of each frequency band of EEG. The results show that brain areas are activated of the central area when people say "yes", and the areas are activated of the central area and temporal when people say "no". This conclusion is corresponding to magnetic resonance imaging technology. This study provides the theory basis and the algorithm design basis for designing BCI equipment for people with neuromuscular disorders.

  7. Enhanced peripheral visual processing in congenitally deaf humans is supported by multiple brain regions, including primary auditory cortex

    PubMed Central

    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

  8. Noise trauma induced plastic changes in brain regions outside the classical auditory pathway.

    PubMed

    Chen, G-D; Sheppard, A; Salvi, R

    2016-02-19

    The effects of intense noise exposure on the classical auditory pathway have been extensively investigated; however, little is known about the effects of noise-induced hearing loss on non-classical auditory areas in the brain such as the lateral amygdala (LA) and striatum (Str). To address this issue, we compared the noise-induced changes in spontaneous and tone-evoked responses from multiunit clusters (MUC) in the LA and Str with those seen in auditory cortex (AC) in rats. High-frequency octave band noise (10-20 kHz) and narrow band noise (16-20 kHz) induced permanent threshold shifts at high-frequencies within and above the noise band but not at low frequencies. While the noise trauma significantly elevated spontaneous discharge rate (SR) in the AC, SRs in the LA and Str were only slightly increased across all frequencies. The high-frequency noise trauma affected tone-evoked firing rates in frequency and time-dependent manner and the changes appeared to be related to the severity of noise trauma. In the LA, tone-evoked firing rates were reduced at the high-frequencies (trauma area) whereas firing rates were enhanced at the low-frequencies or at the edge-frequency dependent on severity of hearing loss at the high frequencies. The firing rate temporal profile changed from a broad plateau to one sharp, delayed peak. In the AC, tone-evoked firing rates were depressed at high frequencies and enhanced at the low frequencies while the firing rate temporal profiles became substantially broader. In contrast, firing rates in the Str were generally decreased and firing rate temporal profiles become more phasic and less prolonged. The altered firing rate and pattern at low frequencies induced by high-frequency hearing loss could have perceptual consequences. The tone-evoked hyperactivity in low-frequency MUC could manifest as hyperacusis whereas the discharge pattern changes could affect temporal resolution and integration. PMID:26701290

  9. Neural mechanisms of auditory categorization: from across brain areas to within local microcircuits

    PubMed Central

    Tsunada, Joji; Cohen, Yale E.

    2014-01-01

    Categorization enables listeners to efficiently encode and respond to auditory stimuli. Behavioral evidence for auditory categorization has been well documented across a broad range of human and non-human animal species. Moreover, neural correlates of auditory categorization have been documented in a variety of different brain regions in the ventral auditory pathway, which is thought to underlie auditory-object processing and auditory perception. Here, we review and discuss how neural representations of auditory categories are transformed across different scales of neural organization in the ventral auditory pathway: from across different brain areas to within local microcircuits. We propose different neural transformations across different scales of neural organization in auditory categorization. Along the ascending auditory system in the ventral pathway, there is a progression in the encoding of categories from simple acoustic categories to categories for abstract information. On the other hand, in local microcircuits, different classes of neurons differentially compute categorical information. PMID:24987324

  10. A Brain System for Auditory Working Memory

    PubMed Central

    Joseph, Sabine; Gander, Phillip E.; Barascud, Nicolas; Halpern, Andrea R.; Griffiths, Timothy D.

    2016-01-01

    The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. The data support a system for auditory working memory based on the maintenance of sound-specific representations in auditory cortex by projections from higher-order areas, including the hippocampus and frontal cortex. SIGNIFICANCE STATEMENT In this work, we demonstrate a system for maintaining sound in working memory based on activity in auditory cortex, hippocampus, and frontal cortex, and functional connectivity among them. Specifically, our work makes three advances from the previous work. First, we robustly demonstrate hippocampal involvement in all phases of auditory working memory (encoding, maintenance, and retrieval): the role of hippocampus in working memory is controversial. Second, using a pattern classification technique, we show that activity in the auditory cortex and inferior frontal gyrus is specific to the maintained tones in working memory. Third, we show long-range connectivity of auditory cortex to hippocampus and frontal cortex, which may be responsible for keeping such representations active during working memory maintenance. PMID:27098693

  11. Amplitude-modulated stimuli reveal auditory-visual interactions in brain activity and brain connectivity

    PubMed Central

    Laing, Mark; Rees, Adrian; Vuong, Quoc C.

    2015-01-01

    The temporal congruence between auditory and visual signals coming from the same source can be a powerful means by which the brain integrates information from different senses. To investigate how the brain uses temporal information to integrate auditory and visual information from continuous yet unfamiliar stimuli, we used amplitude-modulated tones and size-modulated shapes with which we could manipulate the temporal congruence between the sensory signals. These signals were independently modulated at a slow or a fast rate. Participants were presented with auditory-only, visual-only, or auditory-visual (AV) trials in the fMRI scanner. On AV trials, the auditory and visual signal could have the same (AV congruent) or different modulation rates (AV incongruent). Using psychophysiological interaction analyses, we found that auditory regions showed increased functional connectivity predominantly with frontal regions for AV incongruent relative to AV congruent stimuli. We further found that superior temporal regions, shown previously to integrate auditory and visual signals, showed increased connectivity with frontal and parietal regions for the same contrast. Our findings provide evidence that both activity in a network of brain regions and their connectivity are important for AV integration, and help to bridge the gap between transient and familiar AV stimuli used in previous studies. PMID:26483710

  12. Auditory pattern perception in 'split brain' patients.

    PubMed

    Musiek, F E; Pinheiro, M L; Wilson, D H

    1980-10-01

    Three "split brain" subjects with normal peripheral hearing were tested on identifying monaurally presented auditory intensity and frequency patterns. One subject was tested before commissurotomy, ten days later, and one year after surgery. Results indicated that sectioning the corpus callosum dramatically affects the ability to verbally report both intensity and frequency patterns. However, the ability of the subjects to correctly "hum" frequency patterns was not impaired. Thus, it appears for a correct verbal report of an auditory pattern, interhemispheric transfer of acoustic information is required, while "humming" the pattern does not. Further application of this finding implicates auditory pattern tasks as as a potentially valuable test for detecting problems of higher auditory processing, particularly those affecting interhemispheric interaction. PMID:7417089

  13. [Auditory hallucinations in lesions of the brain stem].

    PubMed

    Cambier, J; Decroix, J P; Masson, C

    1987-01-01

    Since the publication by Jean Lhermitte in 1922 of his paper on hallucinosis, the peduncular type has been described as a purely visual phenomenon. However, limited brain stem lesions can give rise to analogous manifestations in the auditory field. Five cases of auditory hallucinosis are reviewed, the first four resulting from a lesion of tegmentum of pons responsible for contralateral hemi-anesthesia and homolateral facial palsy with paralysis of laterality. Central type hypoacusis and a severe disorder of localization of sounds revealed a lesion of trapezoid body. The fifth case resulted from a peduncular lesion in region supplied by superior cerebellar artery, the auditory deficit being related to a lesion of inferior corpus quadrigeminum. In one patient, the auditory hallucinosis was followed by a period of visual hallucinations and oneiric delusions. Both auditory and visual hallucinosis can be related to hypnagogic hallucinations. Dream mechanisms (the geniculo-occipital spikes system) escape from normal inhibitory control exerted by the raphe nuclei. Auditory deafferentation could predispose to auditory hallucinosis. PMID:3629075

  14. Brain Metabolism during Hallucination-Like Auditory Stimulation in Schizophrenia

    PubMed Central

    Horga, Guillermo; Fernández-Egea, Emilio; Mané, Anna; Font, Mireia; Schatz, Kelly C.; Falcon, Carles; Lomeña, Francisco; Bernardo, Miguel; Parellada, Eduard

    2014-01-01

    Auditory verbal hallucinations (AVH) in schizophrenia are typically characterized by rich emotional content. Despite the prominent role of emotion in regulating normal perception, the neural interface between emotion-processing regions such as the amygdala and auditory regions involved in perception remains relatively unexplored in AVH. Here, we studied brain metabolism using FDG-PET in 9 remitted patients with schizophrenia that previously reported severe AVH during an acute psychotic episode and 8 matched healthy controls. Participants were scanned twice: (1) at rest and (2) during the perception of aversive auditory stimuli mimicking the content of AVH. Compared to controls, remitted patients showed an exaggerated response to the AVH-like stimuli in limbic and paralimbic regions, including the left amygdala. Furthermore, patients displayed abnormally strong connections between the amygdala and auditory regions of the cortex and thalamus, along with abnormally weak connections between the amygdala and medial prefrontal cortex. These results suggest that abnormal modulation of the auditory cortex by limbic-thalamic structures might be involved in the pathophysiology of AVH and may potentially account for the emotional features that characterize hallucinatory percepts in schizophrenia. PMID:24416328

  15. Functional development in the infant brain for auditory pitch processing.

    PubMed

    Homae, Fumitaka; Watanabe, Hama; Nakano, Tamami; Taga, Gentaro

    2012-03-01

    Understanding how the developing brain processes auditory information is a critical step toward the clarification of infants' perception of speech and music. We have reported that the infant brain perceives pitch information in speech sounds. Here, we used multichannel near-infrared spectroscopy to examine whether the infant brain is sensitive to information of pitch changes in auditory sequences. Three types of auditory sequences with distinct temporal structures of pitch changes were presented to 3- and 6-month-old infants: a long condition of 12 successive tones constructing a chromatic scale (600 ms), a short condition of four successive tones constructing a chromatic scale (200 ms), and a random condition of random tone sequences (50 ms per tone). The difference among the conditions was only in the sequential order of the tones, which causes pitch changes between the successive tones. We found that the bilateral temporal regions of both ages of infants showed significant activation under the three conditions. The stimulus-dependent activation was observed in the right temporoparietal region of the both infant groups; the 3- and 6-month-old infants showed the most prominent activation under the random and short conditions, respectively. Our findings indicate that the infant brain, which shows functional differentiation and lateralization in auditory-related areas, is capable of responding to more than single tones of pitch information. These results suggest that the right temporoparietal region of the infants increases sensitivity to auditory sequences, which have temporal structures similar to those of syllables in speech sounds, in the course of development. PMID:21488136

  16. Infant Auditory Processing and Event-related Brain Oscillations

    PubMed Central

    Musacchia, Gabriella; Ortiz-Mantilla, Silvia; Realpe-Bonilla, Teresa; Roesler, Cynthia P.; Benasich, April A.

    2015-01-01

    Rapid auditory processing and acoustic change detection abilities play a critical role in allowing human infants to efficiently process the fine spectral and temporal changes that are characteristic of human language. These abilities lay the foundation for effective language acquisition; allowing infants to hone in on the sounds of their native language. Invasive procedures in animals and scalp-recorded potentials from human adults suggest that simultaneous, rhythmic activity (oscillations) between and within brain regions are fundamental to sensory development; determining the resolution with which incoming stimuli are parsed. At this time, little is known about oscillatory dynamics in human infant development. However, animal neurophysiology and adult EEG data provide the basis for a strong hypothesis that rapid auditory processing in infants is mediated by oscillatory synchrony in discrete frequency bands. In order to investigate this, 128-channel, high-density EEG responses of 4-month old infants to frequency change in tone pairs, presented in two rate conditions (Rapid: 70 msec ISI and Control: 300 msec ISI) were examined. To determine the frequency band and magnitude of activity, auditory evoked response averages were first co-registered with age-appropriate brain templates. Next, the principal components of the response were identified and localized using a two-dipole model of brain activity. Single-trial analysis of oscillatory power showed a robust index of frequency change processing in bursts of Theta band (3 - 8 Hz) activity in both right and left auditory cortices, with left activation more prominent in the Rapid condition. These methods have produced data that are not only some of the first reported evoked oscillations analyses in infants, but are also, importantly, the product of a well-established method of recording and analyzing clean, meticulously collected, infant EEG and ERPs. In this article, we describe our method for infant EEG net

  17. Bilinguals at the "cocktail party": dissociable neural activity in auditory-linguistic brain regions reveals neurobiological basis for nonnative listeners' speech-in-noise recognition deficits.

    PubMed

    Bidelman, Gavin M; Dexter, Lauren

    2015-04-01

    We examined a consistent deficit observed in bilinguals: poorer speech-in-noise (SIN) comprehension for their nonnative language. We recorded neuroelectric mismatch potentials in mono- and bi-lingual listeners in response to contrastive speech sounds in noise. Behaviorally, late bilinguals required ∼10dB more favorable signal-to-noise ratios to match monolinguals' SIN abilities. Source analysis of cortical activity demonstrated monotonic increase in response latency with noise in superior temporal gyrus (STG) for both groups, suggesting parallel degradation of speech representations in auditory cortex. Contrastively, we found differential speech encoding between groups within inferior frontal gyrus (IFG)-adjacent to Broca's area-where noise delays observed in nonnative listeners were offset in monolinguals. Notably, brain-behavior correspondences double dissociated between language groups: STG activation predicted bilinguals' SIN, whereas IFG activation predicted monolinguals' performance. We infer higher-order brain areas act compensatorily to enhance impoverished sensory representations but only when degraded speech recruits linguistic brain mechanisms downstream from initial auditory-sensory inputs. PMID:25747886

  18. Specific activation of operculum 3 (OP3) brain region during provoked tinnitus-related phantom auditory perceptions in humans.

    PubMed

    Job, Agnès; Jacob, Roland; Pons, Yoann; Raynal, Marc; Kossowski, Michel; Gauthier, Jérôme; Lombard, Bertrand; Delon-Martin, Chantal

    2016-03-01

    The phantom sound perception mechanism by which a sound perception occurs without any external sound source is still enigmatic. According to our previous fMRI study, a small region in the parietal operculum 3 was hyperactivated as a function of tinnitus periodicity in subjects with acoustic trauma tinnitus sequelae. This region was localized in the vicinity of neural correlates of middle-ear tympano-ossicular chain movements due to pressure variations. Disturbed proprioceptors are known to trigger illusory perceptions; therefore, we hypothesized that a disturbance of middle-ear proprioceptors may originate phantom sound perceptions. We designed an fMRI study that aimed to stimulate middle-ear proprioceptors by repetitive vibrations using various rates of click trains. In this study, we report that exposure to specific rates of stimuli for a few minutes at comfortable intensity level in healthy subjects distinctly triggered transient tinnitus-like aftereffects. The fMRI neural correlates of the aftereffects were unequivocally localized in the same parietal region as in acoustic trauma tinnitus sufferers. Our results strongly suggest that a middle-ear kinesthetic/proprioceptive illusion exists at the origin of acoustic trauma tinnitus via a somatosensory pathway encompassing the trigeminal system. PMID:25503643

  19. Brain network interactions in auditory, visual and linguistic processing.

    PubMed

    Horwitz, Barry; Braun, Allen R

    2004-05-01

    In the paper, we discuss the importance of network interactions between brain regions in mediating performance of sensorimotor and cognitive tasks, including those associated with language processing. Functional neuroimaging, especially PET and fMRI, provide data that are obtained essentially simultaneously from much of the brain, and thus are ideal for enabling one to assess interregional functional interactions. Two ways to use these types of data to assess network interactions are presented. First, using PET, we demonstrate that anterior and posterior perisylvian language areas have stronger functional connectivity during spontaneous narrative production than during other less linguistically demanding production tasks. Second, we show how one can use large-scale neural network modeling to relate neural activity to the hemodynamically-based data generated by fMRI and PET. We review two versions of a model of object processing - one for visual and one for auditory objects. The regions comprising the models include primary and secondary sensory cortex, association cortex in the temporal lobe, and prefrontal cortex. Each model incorporates specific assumptions about how neurons in each of these areas function, and how neurons in the different areas are interconnected with each other. Each model is able to perform a delayed match-to-sample task for simple objects (simple shapes for the visual model; tonal contours for the auditory model). We find that the simulated electrical activities in each region are similar to those observed in nonhuman primates performing analogous tasks, and the absolute values of the simulated integrated synaptic activity in each brain region match human fMRI/PET data. Thus, this type of modeling provides a way to understand the neural bases for the sensorimotor and cognitive tasks of interest. PMID:15068921

  20. Are Auditory Hallucinations Related to the Brain's Resting State Activity? A 'Neurophenomenal Resting State Hypothesis'

    PubMed Central

    2014-01-01

    While several hypotheses about the neural mechanisms underlying auditory verbal hallucinations (AVH) have been suggested, the exact role of the recently highlighted intrinsic resting state activity of the brain remains unclear. Based on recent findings, we therefore developed what we call the 'resting state hypotheses' of AVH. Our hypothesis suggest that AVH may be traced back to abnormally elevated resting state activity in auditory cortex itself, abnormal modulation of the auditory cortex by anterior cortical midline regions as part of the default-mode network, and neural confusion between auditory cortical resting state changes and stimulus-induced activity. We discuss evidence in favour of our 'resting state hypothesis' and show its correspondence with phenomenal, i.e., subjective-experiential features as explored in phenomenological accounts. Therefore I speak of a 'neurophenomenal resting state hypothesis' of auditory hallucinations in schizophrenia. PMID:25598821

  1. Diffusion tensor imaging of dolphin brains reveals direct auditory pathway to temporal lobe

    PubMed Central

    Berns, Gregory S.; Cook, Peter F.; Foxley, Sean; Jbabdi, Saad; Miller, Karla L.; Marino, Lori

    2015-01-01

    The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes' auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of ‘associative′ regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here, we used a novel diffusion tensor imaging (DTI) sequence in archival post-mortem brains of a common dolphin (Delphinus delphis) and a pantropical dolphin (Stenella attenuata) to map their sensory and motor systems. Using thalamic parcellation based on traditionally defined regions for the primary visual (V1) and auditory cortex (A1), we found distinct regions of the thalamus connected to V1 and A1. But in addition to suprasylvian-A1, we report here, for the first time, the auditory cortex also exists in the temporal lobe, in a region near cetacean-A2 and possibly analogous to the primary auditory cortex in related terrestrial mammals (Artiodactyla). Using probabilistic tract tracing, we found a direct pathway from the inferior colliculus to the medial geniculate nucleus to the temporal lobe near the sylvian fissure. Our results demonstrate the feasibility of post-mortem DTI in archival specimens to answer basic questions in comparative neurobiology in a way that has not previously been possible and shows a link between the cetacean auditory system and those of terrestrial mammals. Given that fresh cetacean specimens are relatively rare, the ability to measure connectivity in archival specimens opens up a plethora of possibilities for investigating neuroanatomy in cetaceans and other species

  2. Diffusion tensor imaging of dolphin brains reveals direct auditory pathway to temporal lobe.

    PubMed

    Berns, Gregory S; Cook, Peter F; Foxley, Sean; Jbabdi, Saad; Miller, Karla L; Marino, Lori

    2015-07-22

    The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes' auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of 'associative' regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here, we used a novel diffusion tensor imaging (DTI) sequence in archival post-mortem brains of a common dolphin (Delphinus delphis) and a pantropical dolphin (Stenella attenuata) to map their sensory and motor systems. Using thalamic parcellation based on traditionally defined regions for the primary visual (V1) and auditory cortex (A1), we found distinct regions of the thalamus connected to V1 and A1. But in addition to suprasylvian-A1, we report here, for the first time, the auditory cortex also exists in the temporal lobe, in a region near cetacean-A2 and possibly analogous to the primary auditory cortex in related terrestrial mammals (Artiodactyla). Using probabilistic tract tracing, we found a direct pathway from the inferior colliculus to the medial geniculate nucleus to the temporal lobe near the sylvian fissure. Our results demonstrate the feasibility of post-mortem DTI in archival specimens to answer basic questions in comparative neurobiology in a way that has not previously been possible and shows a link between the cetacean auditory system and those of terrestrial mammals. Given that fresh cetacean specimens are relatively rare, the ability to measure connectivity in archival specimens opens up a plethora of possibilities for investigating neuroanatomy in cetaceans and other species

  3. [Analysis of auditory information in the brain of the cetacean].

    PubMed

    Popov, V V; Supin, A Ia

    2006-01-01

    The cetacean brain specifics involve an exceptional development of the auditory neural centres. The place of projection sensory areas including the auditory that in the cetacean brain cortex is essentially different from that in other mammals. The EP characteristics indicated presence of several functional divisions in the auditory cortex. Physiological studies of the cetacean auditory centres were mainly performed using the EP technique. Of several types of the EPs, the short-latency auditory EP was most thoroughly studied. In cetacean, it is characterised by exceptionally high temporal resolution with the integration time about 0.3 ms which corresponds to the cut-off frequency 1700 Hz. This much exceeds the temporal resolution of the hearing in terranstrial mammals. The frequency selectivity of hearing in cetacean was measured using a number of variants of the masking technique. The hearing frequency selectivity acuity in cetacean exceeds that of most terraneous mammals (excepting the bats). This acute frequency selectivity provides the differentiation among the finest spectral patterns of auditory signals. PMID:16613059

  4. The Human Brain Maintains Contradictory and Redundant Auditory Sensory Predictions

    PubMed Central

    Pieszek, Marika; Widmann, Andreas; Gruber, Thomas; Schröger, Erich

    2013-01-01

    Computational and experimental research has revealed that auditory sensory predictions are derived from regularities of the current environment by using internal generative models. However, so far, what has not been addressed is how the auditory system handles situations giving rise to redundant or even contradictory predictions derived from different sources of information. To this end, we measured error signals in the event-related brain potentials (ERPs) in response to violations of auditory predictions. Sounds could be predicted on the basis of overall probability, i.e., one sound was presented frequently and another sound rarely. Furthermore, each sound was predicted by an informative visual cue. Participants’ task was to use the cue and to discriminate the two sounds as fast as possible. Violations of the probability based prediction (i.e., a rare sound) as well as violations of the visual-auditory prediction (i.e., an incongruent sound) elicited error signals in the ERPs (Mismatch Negativity [MMN] and Incongruency Response [IR]). Particular error signals were observed even in case the overall probability and the visual symbol predicted different sounds. That is, the auditory system concurrently maintains and tests contradictory predictions. Moreover, if the same sound was predicted, we observed an additive error signal (scalp potential and primary current density) equaling the sum of the specific error signals. Thus, the auditory system maintains and tolerates functionally independently represented redundant and contradictory predictions. We argue that the auditory system exploits all currently active regularities in order to optimally prepare for future events. PMID:23308266

  5. Shaping the aging brain: role of auditory input patterns in the emergence of auditory cortical impairments

    PubMed Central

    Kamal, Brishna; Holman, Constance; de Villers-Sidani, Etienne

    2013-01-01

    Age-related impairments in the primary auditory cortex (A1) include poor tuning selectivity, neural desynchronization, and degraded responses to low-probability sounds. These changes have been largely attributed to reduced inhibition in the aged brain, and are thought to contribute to substantial hearing impairment in both humans and animals. Since many of these changes can be partially reversed with auditory training, it has been speculated that they might not be purely degenerative, but might rather represent negative plastic adjustments to noisy or distorted auditory signals reaching the brain. To test this hypothesis, we examined the impact of exposing young adult rats to 8 weeks of low-grade broadband noise on several aspects of A1 function and structure. We then characterized the same A1 elements in aging rats for comparison. We found that the impact of noise exposure on A1 tuning selectivity, temporal processing of auditory signal and responses to oddball tones was almost indistinguishable from the effect of natural aging. Moreover, noise exposure resulted in a reduction in the population of parvalbumin inhibitory interneurons and cortical myelin as previously documented in the aged group. Most of these changes reversed after returning the rats to a quiet environment. These results support the hypothesis that age-related changes in A1 have a strong activity-dependent component and indicate that the presence or absence of clear auditory input patterns might be a key factor in sustaining adult A1 function. PMID:24062649

  6. Analysis of auditory information in the brains of cetaceans.

    PubMed

    Popov, V V; Supin, A Ya

    2007-03-01

    A characteristic feature of the brains of toothed cetaceans is the exclusive development of the auditory neural centers. The location of the projection sensory zones, including the auditory zones, in the cetacean cortex is significantly different from that in other mammals. The characteristics of evoked potentials demonstrate the existence of several functional subdivisions in the auditory cortex. Physiological studies of the auditory neural centers of cetaceans have been performed predominantly using the evoked potentials method. Of the several types of evoked potentials available for non-invasive recording, the most detailed studies have been performed using short-latency auditory evoked potentials (SLAEP). SLAEP in cetaceans are characterized by exclusively high time resolution, with integration times of about 0.3 msec, which on the frequency scale corresponds to a cut-off frequency of 1700 Hz. This is more than an order of magnitude greater than the time resolution of hearing in terrestrial mammals. The frequency selectivity of hearing in cetaceans has been measured using several versions of the masking method. The acuity of frequency selectivity in cetaceans is several times greater than that in most terrestrial mammals (except bats). The acute frequency selectivity allows the discrimination of very fine spectral patterns of sound signals. PMID:17294105

  7. The relationship between phonological and auditory processing and brain organization in beginning readers

    PubMed Central

    PUGH, Kenneth R.; LANDI, Nicole; PRESTON, Jonathan L.; MENCL, W. Einar; AUSTIN, Alison C.; SIBLEY, Daragh; FULBRIGHT, Robert K.; SEIDENBERG, Mark S.; GRIGORENKO, Elena L.; CONSTABLE, R. Todd; MOLFESE, Peter; FROST, Stephen J.

    2012-01-01

    We employed brain-behavior analyses to explore the relationship between performance on tasks measuring phonological awareness, pseudoword decoding, and rapid auditory processing (all predictors of reading (dis)ability) and brain organization for print and speech in beginning readers. For print-related activation, we observed a shared set of skill-correlated regions, including left hemisphere temporoparietal and occipitotemporal sites, as well as inferior frontal, visual, visual attention, and subcortical components. For speech-related activation, shared variance among reading skill measures was most prominently correlated with activation in left hemisphere inferior frontal gyrus and precuneus. Implications for brain-based models of literacy acquisition are discussed. PMID:22572517

  8. Concurrent brain responses to separate auditory and visual targets

    PubMed Central

    Mitchell, Daniel J.; Hauk, Olaf; Beste, Christian; Pizzella, Vittorio; Duncan, John

    2015-01-01

    In the attentional blink, a target event (T1) strongly interferes with perception of a second target (T2) presented within a few hundred milliseconds. Concurrently, the brain's electromagnetic response to the second target is suppressed, especially a late negative-positive EEG complex including the traditional P3 wave. An influential theory proposes that conscious perception requires access to a distributed, frontoparietal global workspace, explaining the attentional blink by strong mutual inhibition between concurrent workspace representations. Often, however, the attentional blink is reduced or eliminated for targets in different sensory modalities, suggesting a limit to such global inhibition. Using functional magnetic resonance imaging, we confirm that visual and auditory targets produce similar, distributed patterns of frontoparietal activity. In an attentional blink EEG/MEG design, however, an auditory T1 and visual T2 are identified without mutual interference, with largely preserved electromagnetic responses to T2. The results suggest parallel brain responses to target events in different sensory modalities. PMID:26084914

  9. Concurrent brain responses to separate auditory and visual targets.

    PubMed

    Finoia, Paola; Mitchell, Daniel J; Hauk, Olaf; Beste, Christian; Pizzella, Vittorio; Duncan, John

    2015-08-01

    In the attentional blink, a target event (T1) strongly interferes with perception of a second target (T2) presented within a few hundred milliseconds. Concurrently, the brain's electromagnetic response to the second target is suppressed, especially a late negative-positive EEG complex including the traditional P3 wave. An influential theory proposes that conscious perception requires access to a distributed, frontoparietal global workspace, explaining the attentional blink by strong mutual inhibition between concurrent workspace representations. Often, however, the attentional blink is reduced or eliminated for targets in different sensory modalities, suggesting a limit to such global inhibition. Using functional magnetic resonance imaging, we confirm that visual and auditory targets produce similar, distributed patterns of frontoparietal activity. In an attentional blink EEG/MEG design, however, an auditory T1 and visual T2 are identified without mutual interference, with largely preserved electromagnetic responses to T2. The results suggest parallel brain responses to target events in different sensory modalities. PMID:26084914

  10. An auditory brain-computer interface using virtual sound field.

    PubMed

    Gao, Haiyang; Ouyang, Minhui; Zhang, Dan; Hong, Bo

    2011-01-01

    Brain-computer interfaces (BCIs) exploring the auditory communication channel might be preferable for amyotrophic lateral sclerosis (ALS) patients with poor sight or with the visual system being occupied for other uses. Spatial attention was proven to be able to modulate the event-related potentials (ERPs); yet up to now, there is no auditory BCI based on virtual sound field. In this study, auditory spatial attention was introduced by using stimuli in a virtual sound field. Subjects attended selectively to the virtual location of the target sound and discriminated its relevant properties. The concurrently recorded ERP components and the users' performance were compared with those of the paradigm where all sounds were presented in the frontal direction. The early ERP components (100-250 ms) and the simulated online accuracies indicated that spatial attention indeed added effective discriminative information for BCI classification. The proposed auditory paradigm using virtual sound field may lead to a high-performance and portable BCI system. PMID:22255354

  11. Brain activity during auditory and visual phonological, spatial and simple discrimination tasks.

    PubMed

    Salo, Emma; Rinne, Teemu; Salonen, Oili; Alho, Kimmo

    2013-02-16

    We used functional magnetic resonance imaging to measure human brain activity during tasks demanding selective attention to auditory or visual stimuli delivered in concurrent streams. Auditory stimuli were syllables spoken by different voices and occurring in central or peripheral space. Visual stimuli were centrally or more peripherally presented letters in darker or lighter fonts. The participants performed a phonological, spatial or "simple" (speaker-gender or font-shade) discrimination task in either modality. Within each modality, we expected a clear distinction between brain activations related to nonspatial and spatial processing, as reported in previous studies. However, within each modality, different tasks activated largely overlapping areas in modality-specific (auditory and visual) cortices, as well as in the parietal and frontal brain regions. These overlaps may be due to effects of attention common for all three tasks within each modality or interaction of processing task-relevant features and varying task-irrelevant features in the attended-modality stimuli. Nevertheless, brain activations caused by auditory and visual phonological tasks overlapped in the left mid-lateral prefrontal cortex, while those caused by the auditory and visual spatial tasks overlapped in the inferior parietal cortex. These overlapping activations reveal areas of multimodal phonological and spatial processing. There was also some evidence for intermodal attention-related interaction. Most importantly, activity in the superior temporal sulcus elicited by unattended speech sounds was attenuated during the visual phonological task in comparison with the other visual tasks. This effect might be related to suppression of processing irrelevant speech presumably distracting the phonological task involving the letters. PMID:23261663

  12. Development of auditory-specific brain rhythm in infants.

    PubMed

    Fujioka, Takako; Mourad, Nasser; Trainor, Laurel J

    2011-02-01

    Human infants rapidly develop their auditory perceptual abilities and acquire culture-specific knowledge in speech and music in the second 6 months of life. In the adult brain, neural rhythm around 10 Hz in the temporal lobes is thought to reflect sound analysis and subsequent cognitive processes such as memory and attention. To study when and how such rhythm emerges in infancy, we examined electroencephalogram (EEG) recordings in infants 4 and 12 months of age during sound stimulation and silence. In the 4-month-olds, the amplitudes of narrowly tuned 4-Hz brain rhythm, recorded from bilateral temporal electrodes, were modulated by sound stimuli. In the 12-month-olds, the sound-induced modulation occurred at faster 6-Hz rhythm at temporofrontal locations. The brain rhythms in the older infants consisted of more complex components, as even evident in individual data. These findings suggest that auditory-specific rhythmic neural activity, which is already established before 6 months of age, involves more speed-efficient long-range neural networks by the age of 12 months when long-term memory for native phoneme representation and for musical rhythmic features is formed. We suggest that maturation of distinct rhythmic components occurs in parallel, and that sensory-specific functions bound to particular thalamo-cortical networks are transferred to newly developed higher-order networks step by step until adult hierarchical neural oscillatory mechanisms are achieved across the whole brain. PMID:21226773

  13. Brain Mapping of Language and Auditory Perception in High-Functioning Autistic Adults: A PET Study.

    ERIC Educational Resources Information Center

    Muller, R-A.; Behen, M. E.; Rothermel, R. D.; Chugani, D. C.; Muzik, O.; Mangner, T. J.; Chugani, H. T.

    1999-01-01

    A study used positron emission tomography (PET) to study patterns of brain activation during auditory processing in five high-functioning adults with autism. Results found that participants showed reversed hemispheric dominance during the verbal auditory stimulation and reduced activation of the auditory cortex and cerebellum. (CR)

  14. Localized Brain Activation Related to the Strength of Auditory Learning in a Parrot

    PubMed Central

    Matsushita, Masanori; Matsuda, Yasushi; Takeuchi, Hiro-Aki; Satoh, Ryohei; Watanabe, Aiko; Zandbergen, Matthijs A.; Manabe, Kazuchika; Kawashima, Takashi; Bolhuis, Johan J.

    2012-01-01

    Parrots and songbirds learn their vocalizations from a conspecific tutor, much like human infants acquire spoken language. Parrots can learn human words and it has been suggested that they can use them to communicate with humans. The caudomedial pallium in the parrot brain is homologous with that of songbirds, and analogous to the human auditory association cortex, involved in speech processing. Here we investigated neuronal activation, measured as expression of the protein product of the immediate early gene ZENK, in relation to auditory learning in the budgerigar (Melopsittacus undulatus), a parrot. Budgerigar males successfully learned to discriminate two Japanese words spoken by another male conspecific. Re-exposure to the two discriminanda led to increased neuronal activation in the caudomedial pallium, but not in the hippocampus, compared to untrained birds that were exposed to the same words, or were not exposed to words. Neuronal activation in the caudomedial pallium of the experimental birds was correlated significantly and positively with the percentage of correct responses in the discrimination task. These results suggest that in a parrot, the caudomedial pallium is involved in auditory learning. Thus, in parrots, songbirds and humans, analogous brain regions may contain the neural substrate for auditory learning and memory. PMID:22701714

  15. Tactual and auditory vigilance in split-brain man.

    PubMed Central

    Dimond, S J

    1979-01-01

    Two studies are reported of tactual and auditory vigilance performance in patients with a split-brain or partial commissurotomy to examine the attentional behaviour of the right and left hemisphere, and to identify defects in attention which may be related to the division of the cerebral commissures. The performance of the right hemisphere on all tasks of sustained attention so far studied was substantially better than that of the left. Considerable depletion of concentration was observed for the total split-brain group but not in patients with partial commissurotomy. One of the more unusual phenomena of the split-brain condition is that gaps of attention, often lasting many seconds, occur predominantly on the left hemisphere. The switch to a different type of signal on the same hemisphere does not stop them but the switching of signals from one hemisphere to another does. The defect is interpreted as a failure of attention peculiar to the individual hemisphere under test. PMID:762586

  16. Responses to Vocalizations and Auditory Controls in the Human Newborn Brain

    PubMed Central

    Cristia, Alejandrina; Minagawa, Yasuyo; Dupoux, Emmanuel

    2014-01-01

    In the adult brain, speech can recruit a brain network that is overlapping with, but not identical to, that involved in perceiving non-linguistic vocalizations. Using the same stimuli that had been presented to human 4-month-olds and adults, as well as adult macaques, we sought to shed light on the cortical networks engaged when human newborns process diverse vocalization types. Near infrared spectroscopy was used to register the response of 40 newborns' perisylvian regions when stimulated with speech, human and macaque emotional vocalizations, as well as auditory controls where the formant structure was destroyed but the long-term spectrum was retained. Left fronto-temporal and parietal regions were significantly activated in the comparison of stimulation versus rest, with unclear selectivity in cortical activation. These results for the newborn brain are qualitatively and quantitatively compared with previous work on newborns, older human infants, adult humans, and adult macaques reported in previous work. PMID:25517997

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

    PubMed

    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

  18. Behavioral and electrophysiological auditory processing measures in traumatic brain injury after acoustically controlled auditory training: a long-term study

    PubMed Central

    Figueiredo, Carolina Calsolari; de Andrade, Adriana Neves; Marangoni-Castan, Andréa Tortosa; Gil, Daniela; Suriano, Italo Capraro

    2015-01-01

    ABSTRACT Objective To investigate the long-term efficacy of acoustically controlled auditory training in adults after tarumatic brain injury. Methods A total of six audioogically normal individuals aged between 20 and 37 years were studied. They suffered severe traumatic brain injury with diffuse axional lesion and underwent an acoustically controlled auditory training program approximately one year before. The results obtained in the behavioral and electrophysiological evaluation of auditory processing immediately after acoustically controlled auditory training were compared to reassessment findings, one year later. Results Quantitative analysis of auditory brainsteim response showed increased absolute latency of all waves and interpeak intervals, bilaterraly, when comparing both evaluations. Moreover, increased amplitude of all waves, and the wave V amplitude was statistically significant for the right ear, and wave III for the left ear. As to P3, decreased latency and increased amplitude were found for both ears in reassessment. The previous and current behavioral assessment showed similar results, except for the staggered spondaic words in the left ear and the amount of errors on the dichotic consonant-vowel test. Conclusion The acoustically controlled auditory training was effective in the long run, since better latency and amplitude results were observed in the electrophysiological evaluation, in addition to stability of behavioral measures after one-year training. PMID:26676270

  19. Brain Network Interactions in Auditory, Visual and Linguistic Processing

    ERIC Educational Resources Information Center

    Horwitz, Barry; Braun, Allen R.

    2004-01-01

    In the paper, we discuss the importance of network interactions between brain regions in mediating performance of sensorimotor and cognitive tasks, including those associated with language processing. Functional neuroimaging, especially PET and fMRI, provide data that are obtained essentially simultaneously from much of the brain, and thus are…

  20. Bigger Brains or Bigger Nuclei? Regulating the Size of Auditory Structures in Birds

    PubMed Central

    Kubke, M. Fabiana; Massoglia, Dino P.; Carr, Catherine E.

    2012-01-01

    Increases in the size of the neuronal structures that mediate specific behaviors are believed to be related to enhanced computational performance. It is not clear, however, what developmental and evolutionary mechanisms mediate these changes, nor whether an increase in the size of a given neuronal population is a general mechanism to achieve enhanced computational ability. We addressed the issue of size by analyzing the variation in the relative number of cells of auditory structures in auditory specialists and generalists. We show that bird species with different auditory specializations exhibit variation in the relative size of their hindbrain auditory nuclei. In the barn owl, an auditory specialist, the hind-brain auditory nuclei involved in the computation of sound location show hyperplasia. This hyperplasia was also found in songbirds, but not in non-auditory specialists. The hyperplasia of auditory nuclei was also not seen in birds with large body weight suggesting that the total number of cells is selected for in auditory specialists. In barn owls, differences observed in the relative size of the auditory nuclei might be attributed to modifications in neurogenesis and cell death. Thus, hyperplasia of circuits used for auditory computation accompanies auditory specialization in different orders of birds. PMID:14726625

  1. Connectivity in the human brain dissociates entropy and complexity of auditory inputs.

    PubMed

    Nastase, Samuel A; Iacovella, Vittorio; Davis, Ben; Hasson, Uri

    2015-03-01

    Complex systems are described according to two central dimensions: (a) the randomness of their output, quantified via entropy; and (b) their complexity, which reflects the organization of a system's generators. Whereas some approaches hold that complexity can be reduced to uncertainty or entropy, an axiom of complexity science is that signals with very high or very low entropy are generated by relatively non-complex systems, while complex systems typically generate outputs with entropy peaking between these two extremes. In understanding their environment, individuals would benefit from coding for both input entropy and complexity; entropy indexes uncertainty and can inform probabilistic coding strategies, whereas complexity reflects a concise and abstract representation of the underlying environmental configuration, which can serve independent purposes, e.g., as a template for generalization and rapid comparisons between environments. Using functional neuroimaging, we demonstrate that, in response to passively processed auditory inputs, functional integration patterns in the human brain track both the entropy and complexity of the auditory signal. Connectivity between several brain regions scaled monotonically with input entropy, suggesting sensitivity to uncertainty, whereas connectivity between other regions tracked entropy in a convex manner consistent with sensitivity to input complexity. These findings suggest that the human brain simultaneously tracks the uncertainty of sensory data and effectively models their environmental generators. PMID:25536493

  2. Connectivity in the human brain dissociates entropy and complexity of auditory inputs☆

    PubMed Central

    Nastase, Samuel A.; Iacovella, Vittorio; Davis, Ben; Hasson, Uri

    2015-01-01

    Complex systems are described according to two central dimensions: (a) the randomness of their output, quantified via entropy; and (b) their complexity, which reflects the organization of a system's generators. Whereas some approaches hold that complexity can be reduced to uncertainty or entropy, an axiom of complexity science is that signals with very high or very low entropy are generated by relatively non-complex systems, while complex systems typically generate outputs with entropy peaking between these two extremes. In understanding their environment, individuals would benefit from coding for both input entropy and complexity; entropy indexes uncertainty and can inform probabilistic coding strategies, whereas complexity reflects a concise and abstract representation of the underlying environmental configuration, which can serve independent purposes, e.g., as a template for generalization and rapid comparisons between environments. Using functional neuroimaging, we demonstrate that, in response to passively processed auditory inputs, functional integration patterns in the human brain track both the entropy and complexity of the auditory signal. Connectivity between several brain regions scaled monotonically with input entropy, suggesting sensitivity to uncertainty, whereas connectivity between other regions tracked entropy in a convex manner consistent with sensitivity to input complexity. These findings suggest that the human brain simultaneously tracks the uncertainty of sensory data and effectively models their environmental generators. PMID:25536493

  3. Proteome rearrangements after auditory learning: high-resolution profiling of synapse-enriched protein fractions from mouse brain.

    PubMed

    Kähne, Thilo; Richter, Sandra; Kolodziej, Angela; Smalla, Karl-Heinz; Pielot, Rainer; Engler, Alexander; Ohl, Frank W; Dieterich, Daniela C; Seidenbecher, Constanze; Tischmeyer, Wolfgang; Naumann, Michael; Gundelfinger, Eckart D

    2016-07-01

    Learning and memory processes are accompanied by rearrangements of synaptic protein networks. While various studies have demonstrated the regulation of individual synaptic proteins during these processes, much less is known about the complex regulation of synaptic proteomes. Recently, we reported that auditory discrimination learning in mice is associated with a relative down-regulation of proteins involved in the structural organization of synapses in various brain regions. Aiming at the identification of biological processes and signaling pathways involved in auditory memory formation, here, a label-free quantification approach was utilized to identify regulated synaptic junctional proteins and phosphoproteins in the auditory cortex, frontal cortex, hippocampus, and striatum of mice 24 h after the learning experiment. Twenty proteins, including postsynaptic scaffolds, actin-remodeling proteins, and RNA-binding proteins, were regulated in at least three brain regions pointing to common, cross-regional mechanisms. Most of the detected synaptic proteome changes were, however, restricted to individual brain regions. For example, several members of the Septin family of cytoskeletal proteins were up-regulated only in the hippocampus, while Septin-9 was down-regulated in the hippocampus, the frontal cortex, and the striatum. Meta analyses utilizing several databases were employed to identify underlying cellular functions and biological pathways. Data are available via ProteomeExchange with identifier PXD003089. How does the protein composition of synapses change in different brain areas upon auditory learning? We unravel discrete proteome changes in mouse auditory cortex, frontal cortex, hippocampus, and striatum functionally implicated in the learning process. We identify not only common but also area-specific biological pathways and cellular processes modulated 24 h after training, indicating individual contributions of the regions to memory processing. PMID

  4. The importance of individual frequencies of endogenous brain oscillations for auditory cognition - A short review.

    PubMed

    Baltus, Alina; Herrmann, Christoph Siegfried

    2016-06-01

    Oscillatory EEG activity in the human brain with frequencies in the gamma range (approx. 30-80Hz) is known to be relevant for a large number of cognitive processes. Interestingly, each subject reveals an individual frequency of the auditory gamma-band response (GBR) that coincides with the peak in the auditory steady state response (ASSR). A common resonance frequency of auditory cortex seems to underlie both the individual frequency of the GBR and the peak of the ASSR. This review sheds light on the functional role of oscillatory gamma activity for auditory processing. For successful processing, the auditory system has to track changes in auditory input over time and store information about past events in memory which allows the construction of auditory objects. Recent findings support the idea of gamma oscillations being involved in the partitioning of auditory input into discrete samples to facilitate higher order processing. We review experiments that seem to suggest that inter-individual differences in the resonance frequency are behaviorally relevant for gap detection and speech processing. A possible application of these resonance frequencies for brain computer interfaces is illustrated with regard to optimized individual presentation rates for auditory input to correspond with endogenous oscillatory activity. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26453287

  5. Auditory sequence processing reveals evolutionarily conserved regions of frontal cortex in macaques and humans.

    PubMed

    Wilson, Benjamin; Kikuchi, Yukiko; Sun, Li; Hunter, David; Dick, Frederic; Smith, Kenny; Thiele, Alexander; Griffiths, Timothy D; Marslen-Wilson, William D; Petkov, Christopher I

    2015-01-01

    An evolutionary account of human language as a neurobiological system must distinguish between human-unique neurocognitive processes supporting language and evolutionarily conserved, domain-general processes that can be traced back to our primate ancestors. Neuroimaging studies across species may determine whether candidate neural processes are supported by homologous, functionally conserved brain areas or by different neurobiological substrates. Here we use functional magnetic resonance imaging in Rhesus macaques and humans to examine the brain regions involved in processing the ordering relationships between auditory nonsense words in rule-based sequences. We find that key regions in the human ventral frontal and opercular cortex have functional counterparts in the monkey brain. These regions are also known to be associated with initial stages of human syntactic processing. This study raises the possibility that certain ventral frontal neural systems, which play a significant role in language function in modern humans, originally evolved to support domain-general abilities involved in sequence processing. PMID:26573340

  6. Auditory sequence processing reveals evolutionarily conserved regions of frontal cortex in macaques and humans

    PubMed Central

    Wilson, Benjamin; Kikuchi, Yukiko; Sun, Li; Hunter, David; Dick, Frederic; Smith, Kenny; Thiele, Alexander; Griffiths, Timothy D.; Marslen-Wilson, William D.; Petkov, Christopher I.

    2015-01-01

    An evolutionary account of human language as a neurobiological system must distinguish between human-unique neurocognitive processes supporting language and evolutionarily conserved, domain-general processes that can be traced back to our primate ancestors. Neuroimaging studies across species may determine whether candidate neural processes are supported by homologous, functionally conserved brain areas or by different neurobiological substrates. Here we use functional magnetic resonance imaging in Rhesus macaques and humans to examine the brain regions involved in processing the ordering relationships between auditory nonsense words in rule-based sequences. We find that key regions in the human ventral frontal and opercular cortex have functional counterparts in the monkey brain. These regions are also known to be associated with initial stages of human syntactic processing. This study raises the possibility that certain ventral frontal neural systems, which play a significant role in language function in modern humans, originally evolved to support domain-general abilities involved in sequence processing. PMID:26573340

  7. Spect-studies of the brain with stimulation of the auditory cortex.

    PubMed

    Schadel, A

    1988-01-01

    The radiopharmaceutical N-isopropyl-p-J-Amphetamin (IMP) permits a new approach in the study of cerebral perfusion and function. We advanced the hypothesis for an increased IMP-uptake on auditory cortex during stimulation by white noise. Auditory stimulation activates the auditory cortex. This is marked by an increased IMP-uptake. IMP-uptake by the auditory region on the left side during stimulation on the right ear is another evidence of the crossing of central auditory pathways to the contralateral side. PMID:3265798

  8. [Verbal auditory agnosia: SPECT study of the brain].

    PubMed

    Carmona, C; Casado, I; Fernández-Rojas, J; Garín, J; Rayo, J I

    1995-01-01

    Verbal auditory agnosia are rare in clinical practice. Clinically, it characterized by impairment of comprehension and repetition of speech but reading, writing, and spontaneous speech are preserved. So it is distinguished from generalized auditory agnosia by the preserved ability to recognize non verbal sounds. We present the clinical picture of a forty-years-old, right handed woman who developed verbal auditory agnosic after an bilateral temporal ischemic infarcts due to atrial fibrillation by dilated cardiomyopathie. Neurophysiological studies by pure tone threshold audiometry: brainstem auditory evoked potentials and cortical auditory evoked potentials showed sparing of peripheral hearing and intact auditory pathway in brainstem but impaired cortical responses. Cranial CT-SCAN revealed two large hypodenses area involving both cortico-subcortical temporal lobes. Cerebral SPECT using 99mTc-HMPAO as radiotracer showed hypoperfusion just posterior in both frontal lobes nect to Roland's fissure and at level of bitemporal lobes just anterior to Sylvian's fissure. PMID:8556589

  9. An auditory brain-computer interface evoked by natural speech

    NASA Astrophysics Data System (ADS)

    Lopez-Gordo, M. A.; Fernandez, E.; Romero, S.; Pelayo, F.; Prieto, Alberto

    2012-06-01

    Brain-computer interfaces (BCIs) are mainly intended for people unable to perform any muscular movement, such as patients in a complete locked-in state. The majority of BCIs interact visually with the user, either in the form of stimulation or biofeedback. However, visual BCIs challenge their ultimate use because they require the subjects to gaze, explore and shift eye-gaze using their muscles, thus excluding patients in a complete locked-in state or under the condition of the unresponsive wakefulness syndrome. In this study, we present a novel fully auditory EEG-BCI based on a dichotic listening paradigm using human voice for stimulation. This interface has been evaluated with healthy volunteers, achieving an average information transmission rate of 1.5 bits min-1 in full-length trials and 2.7 bits min-1 using the optimal length of trials, recorded with only one channel and without formal training. This novel technique opens the door to a more natural communication with users unable to use visual BCIs, with promising results in terms of performance, usability, training and cognitive effort.

  10. Brain hyper-reactivity to auditory novel targets in children with high-functioning autism.

    PubMed

    Gomot, Marie; Belmonte, Matthew K; Bullmore, Edward T; Bernard, Frédéric A; Baron-Cohen, Simon

    2008-09-01

    Although communication and social difficulties in autism have received a great deal of research attention, the other key diagnostic feature, extreme repetitive behaviour and unusual narrow interests, has been addressed less often. Also known as 'resistance to change' this may be related to atypical processing of infrequent, novel stimuli. This can be tested at sensory and neural levels. Our aims were to (i) examine auditory novelty detection and its neural basis in children with autism spectrum conditions (ASC) and (ii) test for brain activation patterns that correlate quantitatively with number of autistic traits as a test of the dimensional nature of ASC. The present study employed event-related fMRI during a novel auditory detection paradigm. Participants were twelve 10- to 15-year-old children with ASC and a group of 12 age-, IQ- and sex-matched typical controls. The ASC group responded faster to novel target stimuli. Group differences in brain activity mainly involved the right prefrontal-premotor and the left inferior parietal regions, which were more activated in the ASC group than in controls. In both groups, activation of prefrontal regions during target detection was positively correlated with Autism Spectrum Quotient scores measuring the number of autistic traits. These findings suggest that target detection in autism is associated not only with superior behavioural performance (shorter reaction time) but also with activation of a more widespread network of brain regions. This pattern also shows quantitative variation with number of autistic traits, in a continuum that extends to the normal population. This finding may shed light on the neurophysiological process underlying narrow interests and what clinically is called 'need for sameness'. PMID:18669482

  11. Effectiveness of direct and non-direct auditory stimulation on coma arousal after traumatic brain injury.

    PubMed

    Park, Soohyun; Davis, Alice E

    2016-08-01

    The aim of this study was to evaluate the effect of direct and non-direct auditory stimulation on arousal in coma patients with severe traumatic brain injury and to compare the effects of direct vs. non-direct auditory stimulation. A crossover intervention study design was used. Nine participants who were comatose after a severe traumatic brain injury underwent direct and non-direct auditory stimulation. Direct auditory stimulation requires a higher level of interpersonal interaction between the patient and stimuli such as voices of family members, orientation by a nurse or family member and familiar music. In contrast, non-direct auditory stimuli were characterized as more general, less familiar, less interactive, indirect and not lively such as general music and TV sounds. Participants received both direct and non-direct auditory stimulation in randomized order for 15 minutes. Recovery of consciousness was measured with the Glasgow Coma Scale (GCS) and Sensory Stimulation Assessment Measure (SSAM). The Friedman test with post hoc analysis by Wilcoxon's signed-rank test comparisons was used for data analysis. Patients who received both direct and non-direct auditory stimulation exhibited significantly increased GCS (p = 0.008) and SSAM scores (p = 0.008) over baseline. The improvement in SSAM scores after direct auditory stimulation was significantly greater than that after non-direct auditory stimulation (p = 0.021), but there was no statistically significant difference in GCS scores (p = 0.139). Auditory stimulation, in particular direct auditory stimulation, might be useful for improving the recovery of consciousness and increasing the arousal of comatose patients. The SSAM is more useful for detecting subtle changes from stimulation intervention than the GCS. PMID:27241789

  12. High-Resolution Mapping of Myeloarchitecture In Vivo: Localization of Auditory Areas in the Human Brain.

    PubMed

    De Martino, Federico; Moerel, Michelle; Xu, Junqian; van de Moortele, Pierre-Francois; Ugurbil, Kamil; Goebel, Rainer; Yacoub, Essa; Formisano, Elia

    2015-10-01

    The precise delineation of auditory areas in vivo remains problematic. Histological analysis of postmortem tissue indicates that the relation of areal borders to macroanatomical landmarks is variable across subjects. Furthermore, functional parcellation schemes based on measures of, for example, frequency preference (tonotopy) remain controversial. Here, we propose a 7 Tesla magnetic resonance imaging method that enables the anatomical delineation of auditory cortical areas in vivo and in individual brains, through the high-resolution visualization (0.6 × 0.6 × 0.6 mm(3)) of intracortical anatomical contrast related to myelin. The approach combines the acquisition and analysis of images with multiple MR contrasts (T1, T2*, and proton density). Compared with previous methods, the proposed solution is feasible at high fields and time efficient, which allows collecting myelin-related and functional images within the same measurement session. Our results show that a data-driven analysis of cortical depth-dependent profiles of anatomical contrast allows identifying a most densely myelinated cortical region on the medial Heschl's gyrus. Analyses of functional responses show that this region includes neuronal populations with typical primary functional properties (single tonotopic gradient and narrow frequency tuning), thus indicating that it may correspond to the human homolog of monkey A1. PMID:24994817

  13. Auditory Hallucinations and the Brain's Resting-State Networks: Findings and Methodological Observations.

    PubMed

    Alderson-Day, Ben; Diederen, Kelly; Fernyhough, Charles; Ford, Judith M; Horga, Guillermo; Margulies, Daniel S; McCarthy-Jones, Simon; Northoff, Georg; Shine, James M; Turner, Jessica; van de Ven, Vincent; van Lutterveld, Remko; Waters, Flavie; Jardri, Renaud

    2016-09-01

    In recent years, there has been increasing interest in the potential for alterations to the brain's resting-state networks (RSNs) to explain various kinds of psychopathology. RSNs provide an intriguing new explanatory framework for hallucinations, which can occur in different modalities and population groups, but which remain poorly understood. This collaboration from the International Consortium on Hallucination Research (ICHR) reports on the evidence linking resting-state alterations to auditory hallucinations (AH) and provides a critical appraisal of the methodological approaches used in this area. In the report, we describe findings from resting connectivity fMRI in AH (in schizophrenia and nonclinical individuals) and compare them with findings from neurophysiological research, structural MRI, and research on visual hallucinations (VH). In AH, various studies show resting connectivity differences in left-hemisphere auditory and language regions, as well as atypical interaction of the default mode network and RSNs linked to cognitive control and salience. As the latter are also evident in studies of VH, this points to a domain-general mechanism for hallucinations alongside modality-specific changes to RSNs in different sensory regions. However, we also observed high methodological heterogeneity in the current literature, affecting the ability to make clear comparisons between studies. To address this, we provide some methodological recommendations and options for future research on the resting state and hallucinations. PMID:27280452

  14. The Relationship between Phonological and Auditory Processing and Brain Organization in Beginning Readers

    ERIC Educational Resources Information Center

    Pugh, Kenneth R.; Landi, Nicole; Preston, Jonathan L.; Mencl, W. Einar; Austin, Alison C.; Sibley, Daragh; Fulbright, Robert K.; Seidenberg, Mark S.; Grigorenko, Elena L.; Constable, R. Todd; Molfese, Peter; Frost, Stephen J.

    2013-01-01

    We employed brain-behavior analyses to explore the relationship between performance on tasks measuring phonological awareness, pseudoword decoding, and rapid auditory processing (all predictors of reading (dis)ability) and brain organization for print and speech in beginning readers. For print-related activation, we observed a shared set of…

  15. Ensembling brain regions for brain decoding.

    PubMed

    Alkan, Sarper; Yarman-Vural, Fatos T

    2015-08-01

    In this study, we propose a new method which ensembles the brain regions for brain decoding. The ensemble is generated by clustering the fMRI images recorded during an experimental set-up which measures the cognitive states associated to semantic categories. Initially, voxel clusters are formed by using hierarchical agglomerative clustering with correlation as the similarity metric. Then, for each voxel cluster, a support vector machine (SVM) classifier is trained to estimate the class-posteriori probabilities. Lastly, the class-posteriori probabilities are ensembled by concatenating them under the same feature space, which are then used to train a meta-layer SVM for the final classification of the cognitive states. By using the voxel clusters, we aim to utilize the distributed, but complementing nature of the semantic representations in the brain and improve the classification accuracy. Thus, we make an existential claim that the brain regions provide a natural basis for ensemble learning which should be superior to the random clusters formed over a selected set of voxels. Our approach yields to better classification accuracies in Mitchell dataset on most of the subjects, when compared to state-of-the-art which emphasizes voxel selection and ensemble learning with random subspaces. PMID:26736910

  16. Brain activity during divided and selective attention to auditory and visual sentence comprehension tasks

    PubMed Central

    Moisala, Mona; Salmela, Viljami; Salo, Emma; Carlson, Synnöve; Vuontela, Virve; Salonen, Oili; Alho, Kimmo

    2015-01-01

    Using functional magnetic resonance imaging (fMRI), we measured brain activity of human participants while they performed a sentence congruence judgment task in either the visual or auditory modality separately, or in both modalities simultaneously. Significant performance decrements were observed when attention was divided between the two modalities compared with when one modality was selectively attended. Compared with selective attention (i.e., single tasking), divided attention (i.e., dual-tasking) did not recruit additional cortical regions, but resulted in increased activity in medial and lateral frontal regions which were also activated by the component tasks when performed separately. Areas involved in semantic language processing were revealed predominantly in the left lateral prefrontal cortex by contrasting incongruent with congruent sentences. These areas also showed significant activity increases during divided attention in relation to selective attention. In the sensory cortices, no crossmodal inhibition was observed during divided attention when compared with selective attention to one modality. Our results suggest that the observed performance decrements during dual-tasking are due to interference of the two tasks because they utilize the same part of the cortex. Moreover, semantic dual-tasking did not appear to recruit additional brain areas in comparison with single tasking, and no crossmodal inhibition was observed during intermodal divided attention. PMID:25745395

  17. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    PubMed Central

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders; Fedder, Jens; Laurberg, Peter; Østergaard, John R.; Hertz, Jens Michael; Pedersen, Anders Degn; Gravholt, Claus Højbjerg

    2016-01-01

    Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49) responded to whether the words “GREEN” or “RED” were displayed in green or red (incongruent versus congruent colors). One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying “GREEN” or “RED” had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system. PMID:26958463

  18. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation.

    PubMed

    Wallentin, Mikkel; Skakkebæk, Anne; Bojesen, Anders; Fedder, Jens; Laurberg, Peter; Østergaard, John R; Hertz, Jens Michael; Pedersen, Anders Degn; Gravholt, Claus Højbjerg

    2016-01-01

    Klinefelter syndrome (47, XXY) (KS) is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49) responded to whether the words "GREEN" or "RED" were displayed in green or red (incongruent versus congruent colors). One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying "GREEN" or "RED" had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop) or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system. PMID:26958463

  19. Are you listening? Brain activation associated with sustained nonspatial auditory attention in the presence and absence of stimulation.

    PubMed

    Seydell-Greenwald, Anna; Greenberg, Adam S; Rauschecker, Josef P

    2014-05-01

    Neuroimaging studies investigating the voluntary (top-down) control of attention largely agree that this process recruits several frontal and parietal brain regions. Since most studies used attention tasks requiring several higher-order cognitive functions (e.g. working memory, semantic processing, temporal integration, spatial orienting) as well as different attentional mechanisms (attention shifting, distractor filtering), it is unclear what exactly the observed frontoparietal activations reflect. The present functional magnetic resonance imaging study investigated, within the same participants, signal changes in (1) a "Simple Attention" task in which participants attended to a single melody, (2) a "Selective Attention" task in which they simultaneously ignored another melody, and (3) a "Beep Monitoring" task in which participants listened in silence for a faint beep. Compared to resting conditions with identical stimulation, all tasks produced robust activation increases in auditory cortex, cross-modal inhibition in visual and somatosensory cortex, and decreases in the default mode network, indicating that participants were indeed focusing their attention on the auditory domain. However, signal increases in frontal and parietal brain areas were only observed for tasks 1 and 2, but completely absent for task 3. These results lead to the following conclusions: under most conditions, frontoparietal activations are crucial for attention since they subserve higher-order cognitive functions inherently related to attention. However, under circumstances that minimize other demands, nonspatial auditory attention in the absence of stimulation can be maintained without concurrent frontal or parietal activations. PMID:23913818

  20. [New method for the clinical study of the auditory pathway in the brainstem and cerebral primary and secondary auditory cortex using averaged auditory brain mapping for 15 seconds after sound stimulation].

    PubMed

    Ried Undurraga, E; Ried Goycoolea, E; Cristian Martínez, T

    1999-01-01

    A practical new method for the clinical examination of the auditory pathway from the ear to the brain is presented. Averaging of 4000 stimuli produces a graphic image of evoked potentials in the brainstem and both cerebral hemispheres. We report the results of examination with this new method in 60 normal ears of 30 healthy young people to determine the normal pattern of cerebral processing of evoked auditory signals 5 to 15 milliseconds after stimulating the ear. It is concluded that the examination is useful for studying auditory signal processing in the brain. It also demonstrated that the primary and secondary auditory cortexes are not the destination of the auditory pathway, but relay stations. PMID:10491469

  1. Turning down the noise: the benefit of musical training on the aging auditory brain.

    PubMed

    Alain, Claude; Zendel, Benjamin Rich; Hutka, Stefanie; Bidelman, Gavin M

    2014-02-01

    Age-related decline in hearing abilities is a ubiquitous part of aging, and commonly impacts speech understanding, especially when there are competing sound sources. While such age effects are partially due to changes within the cochlea, difficulties typically exist beyond measurable hearing loss, suggesting that central brain processes, as opposed to simple peripheral mechanisms (e.g., hearing sensitivity), play a critical role in governing hearing abilities late into life. Current training regimens aimed to improve central auditory processing abilities have experienced limited success in promoting listening benefits. Interestingly, recent studies suggest that in young adults, musical training positively modifies neural mechanisms, providing robust, long-lasting improvements to hearing abilities as well as to non-auditory tasks that engage cognitive control. These results offer the encouraging possibility that musical training might be used to counteract age-related changes in auditory cognition commonly observed in older adults. Here, we reviewed studies that have examined the effects of age and musical experience on auditory cognition with an emphasis on auditory scene analysis. We infer that musical training may offer potential benefits to complex listening and might be utilized as a means to delay or even attenuate declines in auditory perception and cognition that often emerge later in life. PMID:23831039

  2. Auditory-musical processing in autism spectrum disorders: a review of behavioral and brain imaging studies.

    PubMed

    Ouimet, Tia; Foster, Nicholas E V; Tryfon, Ana; Hyde, Krista L

    2012-04-01

    Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by atypical social and communication skills, repetitive behaviors, and atypical visual and auditory perception. Studies in vision have reported enhanced detailed ("local") processing but diminished holistic ("global") processing of visual features in ASD. Individuals with ASD also show enhanced processing of simple visual stimuli but diminished processing of complex visual stimuli. Relative to the visual domain, auditory global-local distinctions, and the effects of stimulus complexity on auditory processing in ASD, are less clear. However, one remarkable finding is that many individuals with ASD have enhanced musical abilities, such as superior pitch processing. This review provides a critical evaluation of behavioral and brain imaging studies of auditory processing with respect to current theories in ASD. We have focused on auditory-musical processing in terms of global versus local processing and simple versus complex sound processing. This review contributes to a better understanding of auditory processing differences in ASD. A deeper comprehension of sensory perception in ASD is key to better defining ASD phenotypes and, in turn, may lead to better interventions. PMID:22524375

  3. A blueprint for vocal learning: auditory predispositions from brains to genomes.

    PubMed

    Wheatcroft, David; Qvarnström, Anna

    2015-08-01

    Memorizing and producing complex strings of sound are requirements for spoken human language. We share these behaviours with likely more than 4000 species of songbirds, making birds our primary model for studying the cognitive basis of vocal learning and, more generally, an important model for how memories are encoded in the brain. In songbirds, as in humans, the sounds that a juvenile learns later in life depend on auditory memories formed early in development. Experiments on a wide variety of songbird species suggest that the formation and lability of these auditory memories, in turn, depend on auditory predispositions that stimulate learning when a juvenile hears relevant, species-typical sounds. We review evidence that variation in key features of these auditory predispositions are determined by variation in genes underlying the development of the auditory system. We argue that increased investigation of the neuronal basis of auditory predispositions expressed early in life in combination with modern comparative genomic approaches may provide insights into the evolution of vocal learning. PMID:26246333

  4. A blueprint for vocal learning: auditory predispositions from brains to genomes

    PubMed Central

    Wheatcroft, David; Qvarnström, Anna

    2015-01-01

    Memorizing and producing complex strings of sound are requirements for spoken human language. We share these behaviours with likely more than 4000 species of songbirds, making birds our primary model for studying the cognitive basis of vocal learning and, more generally, an important model for how memories are encoded in the brain. In songbirds, as in humans, the sounds that a juvenile learns later in life depend on auditory memories formed early in development. Experiments on a wide variety of songbird species suggest that the formation and lability of these auditory memories, in turn, depend on auditory predispositions that stimulate learning when a juvenile hears relevant, species-typical sounds. We review evidence that variation in key features of these auditory predispositions are determined by variation in genes underlying the development of the auditory system. We argue that increased investigation of the neuronal basis of auditory predispositions expressed early in life in combination with modern comparative genomic approaches may provide insights into the evolution of vocal learning. PMID:26246333

  5. Auditory information processing during human sleep as revealed by event-related brain potentials.

    PubMed

    Atienza, M; Cantero, J L; Escera, C

    2001-11-01

    The main goal of this review is to elucidate up to what extent pre-attentive auditory information processing is affected during human sleep. Evidence from event-related brain potential (ERP) studies indicates that auditory information processing is selectively affected, even at early phases, across the different stages of sleep-wakefulness continuum. According to these studies, 3 main conclusions are drawn: (1) the sleeping brain is able to automatically detect stimulus occurrence and trigger an orienting response towards that stimulus if its degree of novelty is large; (2) auditory stimuli are represented in the auditory system and maintained for a period of time in sensory memory, making the automatic-change detection during sleep possible; and (3) there are specific brain mechanisms (sleep-specific ERP components associated with the presence of vertex waves and K-complexes) by which information processing can be improved during non-rapid eye movement sleep. However, the remarkably affected amplitude and latency of the waking-ERPs during the different stages of sleep suggests deficits in the building and maintenance of a neural representation of the stimulus as well as in the process by which neural events lead to an orienting response toward such a stimulus. The deactivation of areas in the dorsolateral pre-frontal cortex during sleep contributing to the generation of these ERP components is hypothesized to be one of the main causes for the attenuated amplitude of these ERPs during human sleep. PMID:11682341

  6. Atypical Bilateral Brain Synchronization in the Early Stage of Human Voice Auditory Processing in Young Children with Autism.

    PubMed

    Kurita, Toshiharu; Kikuchi, Mitsuru; Yoshimura, Yuko; Hiraishi, Hirotoshi; Hasegawa, Chiaki; Takahashi, Tetsuya; Hirosawa, Tetsu; Furutani, Naoki; Higashida, Haruhiro; Ikeda, Takashi; Mutou, Kouhei; Asada, Minoru; Minabe, Yoshio

    2016-01-01

    Autism spectrum disorder (ASD) has been postulated to involve impaired neuronal cooperation in large-scale neural networks, including cortico-cortical interhemispheric circuitry. In the context of ASD, alterations in both peripheral and central auditory processes have also attracted a great deal of interest because these changes appear to represent pathophysiological processes; therefore, many prior studies have focused on atypical auditory responses in ASD. The auditory evoked field (AEF), recorded by magnetoencephalography, and the synchronization of these processes between right and left hemispheres was recently suggested to reflect various cognitive abilities in children. However, to date, no previous study has focused on AEF synchronization in ASD subjects. To assess global coordination across spatially distributed brain regions, the analysis of Omega complexity from multichannel neurophysiological data was proposed. Using Omega complexity analysis, we investigated the global coordination of AEFs in 3-8-year-old typically developing (TD) children (n = 50) and children with ASD (n = 50) in 50-ms time-windows. Children with ASD displayed significantly higher Omega complexities compared with TD children in the time-window of 0-50 ms, suggesting lower whole brain synchronization in the early stage of the P1m component. When we analyzed the left and right hemispheres separately, no significant differences in any time-windows were observed. These results suggest lower right-left hemispheric synchronization in children with ASD compared with TD children. Our study provides new evidence of aberrant neural synchronization in young children with ASD by investigating auditory evoked neural responses to the human voice. PMID:27074011

  7. Atypical Bilateral Brain Synchronization in the Early Stage of Human Voice Auditory Processing in Young Children with Autism

    PubMed Central

    Kurita, Toshiharu; Kikuchi, Mitsuru; Yoshimura, Yuko; Hiraishi, Hirotoshi; Hasegawa, Chiaki; Takahashi, Tetsuya; Hirosawa, Tetsu; Furutani, Naoki; Higashida, Haruhiro; Ikeda, Takashi; Mutou, Kouhei; Asada, Minoru; Minabe, Yoshio

    2016-01-01

    Autism spectrum disorder (ASD) has been postulated to involve impaired neuronal cooperation in large-scale neural networks, including cortico-cortical interhemispheric circuitry. In the context of ASD, alterations in both peripheral and central auditory processes have also attracted a great deal of interest because these changes appear to represent pathophysiological processes; therefore, many prior studies have focused on atypical auditory responses in ASD. The auditory evoked field (AEF), recorded by magnetoencephalography, and the synchronization of these processes between right and left hemispheres was recently suggested to reflect various cognitive abilities in children. However, to date, no previous study has focused on AEF synchronization in ASD subjects. To assess global coordination across spatially distributed brain regions, the analysis of Omega complexity from multichannel neurophysiological data was proposed. Using Omega complexity analysis, we investigated the global coordination of AEFs in 3–8-year-old typically developing (TD) children (n = 50) and children with ASD (n = 50) in 50-ms time-windows. Children with ASD displayed significantly higher Omega complexities compared with TD children in the time-window of 0–50 ms, suggesting lower whole brain synchronization in the early stage of the P1m component. When we analyzed the left and right hemispheres separately, no significant differences in any time-windows were observed. These results suggest lower right-left hemispheric synchronization in children with ASD compared with TD children. Our study provides new evidence of aberrant neural synchronization in young children with ASD by investigating auditory evoked neural responses to the human voice. PMID:27074011

  8. Coding space-time stimulus dynamics in auditory brain maps

    PubMed Central

    Wang, Yunyan; Gutfreund, Yoram; Peña, José L.

    2014-01-01

    Sensory maps are often distorted representations of the environment, where ethologically-important ranges are magnified. The implication of a biased representation extends beyond increased acuity for having more neurons dedicated to a certain range. Because neurons are functionally interconnected, non-uniform representations influence the processing of high-order features that rely on comparison across areas of the map. Among these features are time-dependent changes of the auditory scene generated by moving objects. How sensory representation affects high order processing can be approached in the map of auditory space of the owl's midbrain, where locations in the front are over-represented. In this map, neurons are selective not only to location but also to location over time. The tuning to space over time leads to direction selectivity, which is also topographically organized. Across the population, neurons tuned to peripheral space are more selective to sounds moving into the front. The distribution of direction selectivity can be explained by spatial and temporal integration on the non-uniform map of space. Thus, the representation of space can induce biased computation of a second-order stimulus feature. This phenomenon is likely observed in other sensory maps and may be relevant for behavior. PMID:24782781

  9. Estimation of Temporary Change of Brain Activities in Auditory Oddball Paradigm

    NASA Astrophysics Data System (ADS)

    Fukami, Tadanori; Koyanagi, Yusuke; Tanno, Yukinori; Shimada, Takamasa; Akatsuka, Takao; Saito, Yoichi

    In this research, we estimated temporary change of brain activities in auditory oddball paradigm by moving an analysis time window. An advantage of this method is that it can acquire rough changes of activated areas even with data having low time resolution. Eight normal subjects participated in the study, which consisted of a random series of 30 target and 70 nontarget stimuli. We investigated the activated area in three kinds of analysis time sections, from stimulus onset to 5 seconds after the stimulus (time section A), from 2 to 7 seconds after (B) and from 4 to 9 seconds after (C). In time section A, representative activated areas were regions including superior temporal gyrus centered around inferior frontal gyrus, left precentral gyrus corresponding to Broadmann area 6 (BA 6), right fusiform gyrus corresponding to BA 20, bilaterally medial frontal gyrus and right inferior temporal gyrus were activated. In B, we could see the activations in bilatelally cerebellum, inferior frontal gyrus, and region including left motor area. In C, bilatelally postcentral gyrus, left cingulate gyrus , right cerebellum and right insula were activated. Most activations were consistent with previous studies.

  10. Neurogenesis in the brain auditory pathway of a marsupial, the northern native cat (Dasyurus hallucatus)

    SciTech Connect

    Aitkin, L.; Nelson, J.; Farrington, M.; Swann, S. )

    1991-07-08

    Neurogenesis in the auditory pathway of the marsupial Dasyurus hallucatus was studied. Intraperitoneal injections of tritiated thymidine (20-40 microCi) were made into pouch-young varying from 1 to 56 days pouch-life. Animals were killed as adults and brain sections were prepared for autoradiography and counterstained with a Nissl stain. Neurons in the ventral cochlear nucleus were generated prior to 3 days pouch-life, in the superior olive at 5-7 days, and in the dorsal cochlear nucleus over a prolonged period. Inferior collicular neurogenesis lagged behind that in the medial geniculate, the latter taking place between days 3 and 9 and the former between days 7 and 22. Neurogenesis began in the auditory cortex on day 9 and was completed by about day 42. Thus neurogenesis was complete in the medullary auditory nuclei before that in the midbrain commenced, and in the medial geniculate before that in the auditory cortex commenced. The time course of neurogenesis in the auditory pathway of the native cat was very similar to that in another marsupial, the brushtail possum. For both, neurogenesis occurred earlier than in eutherian mammals of a similar size but was more protracted.

  11. You can't stop the music: reduced auditory alpha power and coupling between auditory and memory regions facilitate the illusory perception of music during noise.

    PubMed

    Müller, Nadia; Keil, Julian; Obleser, Jonas; Schulz, Hannah; Grunwald, Thomas; Bernays, René-Ludwig; Huppertz, Hans-Jürgen; Weisz, Nathan

    2013-10-01

    Our brain has the capacity of providing an experience of hearing even in the absence of auditory stimulation. This can be seen as illusory conscious perception. While increasing evidence postulates that conscious perception requires specific brain states that systematically relate to specific patterns of oscillatory activity, the relationship between auditory illusions and oscillatory activity remains mostly unexplained. To investigate this we recorded brain activity with magnetoencephalography and collected intracranial data from epilepsy patients while participants listened to familiar as well as unknown music that was partly replaced by sections of pink noise. We hypothesized that participants have a stronger experience of hearing music throughout noise when the noise sections are embedded in familiar compared to unfamiliar music. This was supported by the behavioral results showing that participants rated the perception of music during noise as stronger when noise was presented in a familiar context. Time-frequency data show that the illusory perception of music is associated with a decrease in auditory alpha power pointing to increased auditory cortex excitability. Furthermore, the right auditory cortex is concurrently synchronized with the medial temporal lobe, putatively mediating memory aspects associated with the music illusion. We thus assume that neuronal activity in the highly excitable auditory cortex is shaped through extensive communication between the auditory cortex and the medial temporal lobe, thereby generating the illusion of hearing music during noise. PMID:23664946

  12. Development and modulation of intrinsic membrane properties control the temporal precision of auditory brain stem neurons.

    PubMed

    Franzen, Delwen L; Gleiss, Sarah A; Berger, Christina; Kümpfbeck, Franziska S; Ammer, Julian J; Felmy, Felix

    2015-01-15

    Passive and active membrane properties determine the voltage responses of neurons. Within the auditory brain stem, refinements in these intrinsic properties during late postnatal development usually generate short integration times and precise action-potential generation. This developmentally acquired temporal precision is crucial for auditory signal processing. How the interactions of these intrinsic properties develop in concert to enable auditory neurons to transfer information with high temporal precision has not yet been elucidated in detail. Here, we show how the developmental interaction of intrinsic membrane parameters generates high firing precision. We performed in vitro recordings from neurons of postnatal days 9-28 in the ventral nucleus of the lateral lemniscus of Mongolian gerbils, an auditory brain stem structure that converts excitatory to inhibitory information with high temporal precision. During this developmental period, the input resistance and capacitance decrease, and action potentials acquire faster kinetics and enhanced precision. Depending on the stimulation time course, the input resistance and capacitance contribute differentially to action-potential thresholds. The decrease in input resistance, however, is sufficient to explain the enhanced action-potential precision. Alterations in passive membrane properties also interact with a developmental change in potassium currents to generate the emergence of the mature firing pattern, characteristic of coincidence-detector neurons. Cholinergic receptor-mediated depolarizations further modulate this intrinsic excitability profile by eliciting changes in the threshold and firing pattern, irrespective of the developmental stage. Thus our findings reveal how intrinsic membrane properties interact developmentally to promote temporally precise information processing. PMID:25355963

  13. Processing of species-specific auditory patterns in the cricket brain by ascending, local, and descending neurons during standing and walking

    PubMed Central

    Zorović, M.

    2011-01-01

    The recognition of the male calling song is essential for phonotaxis in female crickets. We investigated the responses toward different models of song patterns by ascending, local, and descending neurons in the brain of standing and walking crickets. We describe results for two ascending, three local, and two descending interneurons. Characteristic dendritic and axonal arborizations of the local and descending neurons indicate a flow of auditory information from the ascending interneurons toward the lateral accessory lobes and point toward the relevance of this brain region for cricket phonotaxis. Two aspects of auditory processing were studied: the tuning of interneuron activity to pulse repetition rate and the precision of pattern copying. Whereas ascending neurons exhibited weak, low-pass properties, local neurons showed both low- and band-pass properties, and descending neurons represented clear band-pass filters. Accurate copying of single pulses was found at all three levels of the auditory pathway. Animals were walking on a trackball, which allowed an assessment of the effect that walking has on auditory processing. During walking, all neurons were additionally activated, and in most neurons, the spike rate was correlated to walking velocity. The number of spikes elicited by a chirp increased with walking only in ascending neurons, whereas the peak instantaneous spike rate of the auditory responses increased on all levels of the processing pathway. Extra spiking activity resulted in a somewhat degraded copying of the pulse pattern in most neurons. PMID:21346206

  14. Processing of species-specific auditory patterns in the cricket brain by ascending, local, and descending neurons during standing and walking.

    PubMed

    Zorović, M; Hedwig, B

    2011-05-01

    The recognition of the male calling song is essential for phonotaxis in female crickets. We investigated the responses toward different models of song patterns by ascending, local, and descending neurons in the brain of standing and walking crickets. We describe results for two ascending, three local, and two descending interneurons. Characteristic dendritic and axonal arborizations of the local and descending neurons indicate a flow of auditory information from the ascending interneurons toward the lateral accessory lobes and point toward the relevance of this brain region for cricket phonotaxis. Two aspects of auditory processing were studied: the tuning of interneuron activity to pulse repetition rate and the precision of pattern copying. Whereas ascending neurons exhibited weak, low-pass properties, local neurons showed both low- and band-pass properties, and descending neurons represented clear band-pass filters. Accurate copying of single pulses was found at all three levels of the auditory pathway. Animals were walking on a trackball, which allowed an assessment of the effect that walking has on auditory processing. During walking, all neurons were additionally activated, and in most neurons, the spike rate was correlated to walking velocity. The number of spikes elicited by a chirp increased with walking only in ascending neurons, whereas the peak instantaneous spike rate of the auditory responses increased on all levels of the processing pathway. Extra spiking activity resulted in a somewhat degraded copying of the pulse pattern in most neurons. PMID:21346206

  15. Brain stem auditory evoked responses in human infants and adults

    NASA Technical Reports Server (NTRS)

    Hecox, K.; Galambos, R.

    1974-01-01

    Brain stem evoked potentials were recorded by conventional scalp electrodes in infants (3 weeks to 3 years of age) and adults. The latency of one of the major response components (wave V) is shown to be a function both of click intensity and the age of the subject; this latency at a given signal strength shortens postnatally to reach the adult value (about 6 msec) by 12 to 18 months of age. The demonstrated reliability and limited variability of these brain stem electrophysiological responses provide the basis for an optimistic estimate of their usefulness as an objective method for assessing hearing in infants and adults.

  16. Inconsistencies in the correlation between loss of brain stem auditory evoked response waves and postoperative deafness.

    PubMed

    Mustain, W D; al-Mefty, O; Anand, V K

    1992-07-01

    This case underscores the difficulty of predicting postoperative hearing status from brain stem auditory evoked response (BAER) monitoring when wave I is preserved and all later waves are lost. During an operation involving the base of the skull, sudden and irreversible loss of all BAER waves beyond wave I occurred unilaterally. Wave I was preserved, with reduced amplitude and minimal latency shift. There was no permanent postoperative hearing sensitivity loss or speech discrimination loss. PMID:1494930

  17. Reduced resting-state brain activity in the default mode network in children with (central) auditory processing disorders

    PubMed Central

    2014-01-01

    Background In recent years, there has been a growing interest in Central Auditory Processing Disorder (C)APD. However, the neural correlates of (C)APD are poorly understood. Previous neuroimaging experiments have shown changes in the intrinsic activity of the brain in various cognitive deficits and brain disorders. The present study investigated the spontaneous brain activity in (C)APD subjects with resting-state fMRI (rs-fMRI). Methods Thirteen children diagnosed with (C)APD and fifteen age and gender-matched controls participated in a rs-fMRI study during which they were asked to relax keeping their eyes open. Two different techniques of the rs-fMRI data analysis were used: Regional Homogeneity (ReHo) and Independent Component Analysis (ICA), which approach is rare. Results Both methods of data analysis showed comparable results in the pattern of DMN activity within groups. Additionally, ReHo analysis revealed increased co-activation of the superior frontal gyrus, the posterior cingulate cortex/the precuneus in controls, compared to the (C)APD group. ICA yielded inconsistent results across groups. Conclusions Our ReHo results suggest that (C)APD children seem to present reduced regional homogeneity in brain regions considered a part of the default mode network (DMN). These findings might contribute to a better understanding of neural mechanisms of (C)APD. PMID:25261349

  18. “Where Do Auditory Hallucinations Come From?”—A Brain Morphometry Study of Schizophrenia Patients With Inner or Outer Space Hallucinations

    PubMed Central

    Plaze, Marion; Paillère-Martinot, Marie-Laure; Penttilä, Jani; Januel, Dominique; de Beaurepaire, Renaud; Bellivier, Franck; Andoh, Jamila; Galinowski, André; Gallarda, Thierry; Artiges, Eric; Olié, Jean-Pierre; Mangin, Jean-François; Martinot, Jean-Luc

    2011-01-01

    Auditory verbal hallucinations are a cardinal symptom of schizophrenia. Bleuler and Kraepelin distinguished 2 main classes of hallucinations: hallucinations heard outside the head (outer space, or external, hallucinations) and hallucinations heard inside the head (inner space, or internal, hallucinations). This distinction has been confirmed by recent phenomenological studies that identified 3 independent dimensions in auditory hallucinations: language complexity, self-other misattribution, and spatial location. Brain imaging studies in schizophrenia patients with auditory hallucinations have already investigated language complexity and self-other misattribution, but the neural substrate of hallucination spatial location remains unknown. Magnetic resonance images of 45 right-handed patients with schizophrenia and persistent auditory hallucinations and 20 healthy right-handed subjects were acquired. Two homogeneous subgroups of patients were defined based on the hallucination spatial location: patients with only outer space hallucinations (N = 12) and patients with only inner space hallucinations (N = 15). Between-group differences were then assessed using 2 complementary brain morphometry approaches: voxel-based morphometry and sulcus-based morphometry. Convergent anatomical differences were detected between the patient subgroups in the right temporoparietal junction (rTPJ). In comparison to healthy subjects, opposite deviations in white matter volumes and sulcus displacements were found in patients with inner space hallucination and patients with outer space hallucination. The current results indicate that spatial location of auditory hallucinations is associated with the rTPJ anatomy, a key region of the “where” auditory pathway. The detected tilt in the sulcal junction suggests deviations during early brain maturation, when the superior temporal sulcus and its anterior terminal branch appear and merge. PMID:19666833

  19. Endogenous Delta/Theta Sound-Brain Phase Entrainment Accelerates the Buildup of Auditory Streaming.

    PubMed

    Riecke, Lars; Sack, Alexander T; Schroeder, Charles E

    2015-12-21

    In many natural listening situations, meaningful sounds (e.g., speech) fluctuate in slow rhythms among other sounds. When a slow rhythmic auditory stream is selectively attended, endogenous delta (1‒4 Hz) oscillations in auditory cortex may shift their timing so that higher-excitability neuronal phases become aligned with salient events in that stream [1, 2]. As a consequence of this stream-brain phase entrainment [3], these events are processed and perceived more readily than temporally non-overlapping events [4-11], essentially enhancing the neural segregation between the attended stream and temporally noncoherent streams [12]. Stream-brain phase entrainment is robust to acoustic interference [13-20] provided that target stream-evoked rhythmic activity can be segregated from noncoherent activity evoked by other sounds [21], a process that usually builds up over time [22-27]. However, it has remained unclear whether stream-brain phase entrainment functionally contributes to this buildup of rhythmic streams or whether it is merely an epiphenomenon of it. Here, we addressed this issue directly by experimentally manipulating endogenous stream-brain phase entrainment in human auditory cortex with non-invasive transcranial alternating current stimulation (TACS) [28-30]. We assessed the consequences of these manipulations on the perceptual buildup of the target stream (the time required to recognize its presence in a noisy background), using behavioral measures in 20 healthy listeners performing a naturalistic listening task. Experimentally induced cyclic 4-Hz variations in stream-brain phase entrainment reliably caused a cyclic 4-Hz pattern in perceptual buildup time. Our findings demonstrate that strong endogenous delta/theta stream-brain phase entrainment accelerates the perceptual emergence of task-relevant rhythmic streams in noisy environments. PMID:26628008

  20. Can an auditory illusion trick the brain into turning down tinnitus?

    PubMed

    Fletcher, M D; Wiggins, I M

    2014-07-01

    Tinnitus, the phantom perception of sound with no external source, affects an estimated 10-15% of the adult population. Current treatments for this oftentimes distressing condition are of limited effectiveness. The "central gain" model proposes that tinnitus arises from an increase in the responsiveness, or gain, of neurons in central auditory pathways, triggered by damage to the auditory periphery. It has been suggested that tinnitus might be treated by compensating for the peripheral damage, thereby restoring normal levels of input to the central pathways, and hence reducing central gain. Unfortunately, when tinnitus originates with permanent damage to the auditory periphery, it may be impossible to compensate for this damage directly. However, we hypothesize that tinnitus may be treated by tricking the brain into believing that it temporarily receives normal levels of input at frequencies where peripheral damage has occurred. We identify an auditory illusion that seems capable, in principle, of achieving this objective. If effective, this approach would offer a safe, accessible, and non-invasive treatment for tinnitus. PMID:24767808

  1. Can You Hear Me Now? Musical Training Shapes Functional Brain Networks for Selective Auditory Attention and Hearing Speech in Noise

    PubMed Central

    Strait, Dana L.; Kraus, Nina

    2011-01-01

    Even in the quietest of rooms, our senses are perpetually inundated by a barrage of sounds, requiring the auditory system to adapt to a variety of listening conditions in order to extract signals of interest (e.g., one speaker's voice amidst others). Brain networks that promote selective attention are thought to sharpen the neural encoding of a target signal, suppressing competing sounds and enhancing perceptual performance. Here, we ask: does musical training benefit cortical mechanisms that underlie selective attention to speech? To answer this question, we assessed the impact of selective auditory attention on cortical auditory-evoked response variability in musicians and non-musicians. Outcomes indicate strengthened brain networks for selective auditory attention in musicians in that musicians but not non-musicians demonstrate decreased prefrontal response variability with auditory attention. Results are interpreted in the context of previous work documenting perceptual and subcortical advantages in musicians for the hearing and neural encoding of speech in background noise. Musicians’ neural proficiency for selectively engaging and sustaining auditory attention to language indicates a potential benefit of music for auditory training. Given the importance of auditory attention for the development and maintenance of language-related skills, musical training may aid in the prevention, habilitation, and remediation of individuals with a wide range of attention-based language, listening and learning impairments. PMID:21716636

  2. Brain systems for encoding and retrieval of auditory-verbal memory. An in vivo study in humans.

    PubMed

    Fletcher, P C; Frith, C D; Grasby, P M; Shallice, T; Frackowiak, R S; Dolan, R J

    1995-04-01

    Long-term auditory-verbal memory comprises, at a neuropsychological level, a number of distinct cognitive processes. In the present study we determined the brain systems engaged during encoding (experiment 1) and retrieval (experiment 2) of episodic auditory-verbal material. In the separate experiments, PET measurements of regional cerebral blood flow (rCBF), an index of neural activity, were performed in normal volunteers during either the encoding or the retrieval of paired word associates. In experiment 1, a dual task interference paradigm was used to isolate areas involved in episodic encoding from those which would be concurrently activated by other cognitive processes associated with the presentation of paired associates, notably priming. In experiment 2, we used the cued retrieval of paired associates from episodic or from semantic memory in order to isolate the neural correlates of episodic memories. Encoding of episodic memory was associated with activation of the left prefrontal cortex and the retrosplenial area of the cingulate cortex, while retrieval from episodic memory was associated with activation of the precuneus bilaterally and of the right prefrontal cortex. These results are compatible with the patterns of activation reported in a previous PET memory experiment in which encoding and retrieval were studied concurrently. They also indicate that separate brain systems are engaged during the encoding and retrieval phases of episodic auditory-verbal memory. Retrieval from episodic memory engages a different, but overlapping, system to that engaged by retrieval from semantic memory, a finding that lends functional anatomical support to this neuropsychological distinction. PMID:7735882

  3. Comparison of cerebral regional glucose metabolic relationships in resting and auditory stimulated states

    SciTech Connect

    Metter, E.J.; Riege, W.H.; Mazziotta, J.C.; Phelps, M.E.; Kuhl, D.E.

    1984-01-01

    FDG positron computed tomography has demonstrated strong correlations between high frontal and occipital glucose metabolism in normal resting subjects, which varied by age and were lost in Huntington's and Parkinson's Diseases. The studies raised the question whether the findings may be explained by anatomic and not metabolic factors. An approach to the issue was to examine subjects scanned under two states, where functional and not anatomic features would account for relationship differences. Seventeen subjects were identified who had scans under resting and auditory stimulated states. Measurements were taken from 12 brain regions and were expressed as percentage of mean metabolism. A principal components analysis of the resting state demonstrated 3 components (73% of variance), while the stimulated states showed 4 (79% of variance). The first resting factor related frontal, right posterior inferior frontal and superior temporal regions, while in the stimulated, the frontal associated with the occipital. The second resting factor related both angular gyri and posterior temporal, while the third related left posterior inferior frontal, superior temporal and right occipital. With stimulation both factors were replaced by three others. The change in the first factor and its presence in other subject groups points to a functional relationship between the regions. Comparison to previous studies suggest the frontal-occipital association may involve aspects of attention. The variability in other factors was similar to loose correlations noted in normal studies and may reflect the differential response to several tasks.

  4. The WIN-speller: a new intuitive auditory brain-computer interface spelling application

    PubMed Central

    Kleih, Sonja C.; Herweg, Andreas; Kaufmann, Tobias; Staiger-Sälzer, Pit; Gerstner, Natascha; Kübler, Andrea

    2015-01-01

    The objective of this study was to test the usability of a new auditory Brain-Computer Interface (BCI) application for communication. We introduce a word based, intuitive auditory spelling paradigm the WIN-speller. In the WIN-speller letters are grouped by words, such as the word KLANG representing the letters A, G, K, L, and N. Thereby, the decoding step between perceiving a code and translating it to the stimuli it represents becomes superfluous. We tested 11 healthy volunteers and four end-users with motor impairment in the copy spelling mode. Spelling was successful with an average accuracy of 84% in the healthy sample. Three of the end-users communicated with average accuracies of 80% or higher while one user was not able to communicate reliably. Even though further evaluation is required, the WIN-speller represents a potential alternative for BCI based communication in end-users. PMID:26500476

  5. The Wellcome Prize Lecture. A map of auditory space in the mammalian brain: neural computation and development.

    PubMed

    King, A J

    1993-09-01

    The experiments described in this review have demonstrated that the SC contains a two-dimensional map of auditory space, which is synthesized within the brain using a combination of monaural and binaural localization cues. There is also an adaptive fusion of auditory and visual space in this midbrain nucleus, providing for a common access to the motor pathways that control orientation behaviour. This necessitates a highly plastic relationship between the visual and auditory systems, both during postnatal development and in adult life. Because of the independent mobility of difference sense organs, gating mechanisms are incorporated into the auditory representation to provide up-to-date information about the spatial orientation of the eyes and ears. The SC therefore provides a valuable model system for studying a number of important issues in brain function, including the neural coding of sound location, the co-ordination of spatial information between different sensory systems, and the integration of sensory signals with motor outputs. PMID:8240794

  6. Psychophysical and neural correlates of noised-induced tinnitus in animals: Intra- and inter-auditory and non-auditory brain structure studies.

    PubMed

    Zhang, Jinsheng; Luo, Hao; Pace, Edward; Li, Liang; Liu, Bin

    2016-04-01

    Tinnitus, a ringing in the ear or head without an external sound source, is a prevalent health problem. It is often associated with a number of limbic-associated disorders such as anxiety, sleep disturbance, and emotional distress. Thus, to investigate tinnitus, it is important to consider both auditory and non-auditory brain structures. This paper summarizes the psychophysical, immunocytochemical and electrophysiological evidence found in rats or hamsters with behavioral evidence of tinnitus. Behaviorally, we tested for tinnitus using a conditioned suppression/avoidance paradigm, gap detection acoustic reflex behavioral paradigm, and our newly developed conditioned licking suppression paradigm. Our new tinnitus behavioral paradigm requires relatively short baseline training, examines frequency specification of tinnitus perception, and achieves sensitive tinnitus testing at an individual level. To test for tinnitus-related anxiety and cognitive impairment, we used the elevated plus maze and Morris water maze. Our results showed that not all animals with tinnitus demonstrate anxiety and cognitive impairment. Immunocytochemically, we found that animals with tinnitus manifested increased Fos-like immunoreactivity (FLI) in both auditory and non-auditory structures. The manner in which FLI appeared suggests that lower brainstem structures may be involved in acute tinnitus whereas the midbrain and cortex are involved in more chronic tinnitus. Meanwhile, animals with tinnitus also manifested increased FLI in non-auditory brain structures that are involved in autonomic reactions, stress, arousal and attention. Electrophysiologically, we found that rats with tinnitus developed increased spontaneous firing in the auditory cortex (AC) and amygdala (AMG), as well as intra- and inter-AC and AMG neurosynchrony, which demonstrate that tinnitus may be actively produced and maintained by the interactions between the AC and AMG. PMID:26299842

  7. Synchrony of auditory brain responses predicts behavioral ability to keep still in children with autism spectrum disorder: Auditory-evoked response in children with autism spectrum disorder.

    PubMed

    Yoshimura, Yuko; Kikuchi, Mitsuru; Hiraishi, Hirotoshi; Hasegawa, Chiaki; Takahashi, Tetsuya; Remijn, Gerard B; Oi, Manabu; Munesue, Toshio; Higashida, Haruhiro; Minabe, Yoshio

    2016-01-01

    The auditory-evoked P1m, recorded by magnetoencephalography, reflects a central auditory processing ability in human children. One recent study revealed that asynchrony of P1m between the right and left hemispheres reflected a central auditory processing disorder (i.e., attention deficit hyperactivity disorder, ADHD) in children. However, to date, the relationship between auditory P1m right-left hemispheric synchronization and the comorbidity of hyperactivity in children with autism spectrum disorder (ASD) is unknown. In this study, based on a previous report of an asynchrony of P1m in children with ADHD, to clarify whether the P1m right-left hemispheric synchronization is related to the symptom of hyperactivity in children with ASD, we investigated the relationship between voice-evoked P1m right-left hemispheric synchronization and hyperactivity in children with ASD. In addition to synchronization, we investigated the right-left hemispheric lateralization. Our findings failed to demonstrate significant differences in these values between ASD children with and without the symptom of hyperactivity, which was evaluated using the Autism Diagnostic Observational Schedule, Generic (ADOS-G) subscale. However, there was a significant correlation between the degrees of hemispheric synchronization and the ability to keep still during 12-minute MEG recording periods. Our results also suggested that asynchrony in the bilateral brain auditory processing system is associated with ADHD-like symptoms in children with ASD. PMID:27551667

  8. Effects of Visual and Auditory Background on Reading Achievement Test Performance of Brain-Injured and Non Brain-Injured Children.

    ERIC Educational Resources Information Center

    Carter, John L.

    Forty-two brain injured boys and 42 non brain injured boys (aged 11-6 to 12-6) were tested to determine the effects of increasing amounts of visual and auditory distraction on reading performance. The Stanford Achievement Reading Comprehension Test was administered with three degrees of distraction. The visual distraction consisted of either very…

  9. An Auditory-Tactile Visual Saccade-Independent P300 Brain-Computer Interface.

    PubMed

    Yin, Erwei; Zeyl, Timothy; Saab, Rami; Hu, Dewen; Zhou, Zongtan; Chau, Tom

    2016-02-01

    Most P300 event-related potential (ERP)-based brain-computer interface (BCI) studies focus on gaze shift-dependent BCIs, which cannot be used by people who have lost voluntary eye movement. However, the performance of visual saccade-independent P300 BCIs is generally poor. To improve saccade-independent BCI performance, we propose a bimodal P300 BCI approach that simultaneously employs auditory and tactile stimuli. The proposed P300 BCI is a vision-independent system because no visual interaction is required of the user. Specifically, we designed a direction-congruent bimodal paradigm by randomly and simultaneously presenting auditory and tactile stimuli from the same direction. Furthermore, the channels and number of trials were tailored to each user to improve online performance. With 12 participants, the average online information transfer rate (ITR) of the bimodal approach improved by 45.43% and 51.05% over that attained, respectively, with the auditory and tactile approaches individually. Importantly, the average online ITR of the bimodal approach, including the break time between selections, reached 10.77 bits/min. These findings suggest that the proposed bimodal system holds promise as a practical visual saccade-independent P300 BCI. PMID:26678249

  10. Specialization of the auditory processing in harbor porpoise, characterized by brain-stem potentials

    NASA Astrophysics Data System (ADS)

    Bibikov, Nikolay G.

    2002-05-01

    Brain-stem auditory evoked potentials (BAEPs) were recorded from the head surface of the three awaked harbor porpoises (Phocoena phocoena). Silver disk placed on the skin surface above the vertex bone was used as an active electrode. The experiments were performed at the Karadag biological station (the Crimea peninsula). Clicks and tone bursts were used as stimuli. The temporal and frequency selectivity of the auditory system was estimated using the methods of simultaneous and forward masking. An evident minimum of the BAEPs thresholds was observed in the range of 125-135 kHz, where the main spectral component of species-specific echolocation signal is located. In this frequency range the tonal forward masking demonstrated a strong frequency selectivity. Off-response to such tone bursts was a typical observation. An evident BAEP could be recorded up to the frequencies 190-200 kHz, however, outside the acoustical fovea the frequency selectivity was rather poor. Temporal resolution was estimated by measuring BAER recovery functions for double clicks, double tone bursts, and double noise bursts. The half-time of BAERs recovery was in the range of 0.1-0.2 ms. The data indicate that the porpoise auditory system is strongly adapted to detect ultrasonic closely spaced sounds like species-specific locating signals and echoes.

  11. Auditory brain development in premature infants: the importance of early experience.

    PubMed

    McMahon, Erin; Wintermark, Pia; Lahav, Amir

    2012-04-01

    Preterm infants in the neonatal intensive care unit (NICU) often close their eyes in response to bright lights, but they cannot close their ears in response to loud sounds. The sudden transition from the womb to the overly noisy world of the NICU increases the vulnerability of these high-risk newborns. There is a growing concern that the excess noise typically experienced by NICU infants disrupts their growth and development, putting them at risk for hearing, language, and cognitive disabilities. Preterm neonates are especially sensitive to noise because their auditory system is at a critical period of neurodevelopment, and they are no longer shielded by maternal tissue. This paper discusses the developmental milestones of the auditory system and suggests ways to enhance the quality control and type of sounds delivered to NICU infants. We argue that positive auditory experience is essential for early brain maturation and may be a contributing factor for healthy neurodevelopment. Further research is needed to optimize the hospital environment for preterm newborns and to increase their potential to develop into healthy children. PMID:22524335

  12. Simultaneous EEG-fMRI brain signatures of auditory cue utilization

    PubMed Central

    Scharinger, Mathias; Herrmann, Björn; Nierhaus, Till; Obleser, Jonas

    2014-01-01

    Optimal utilization of acoustic cues during auditory categorization is a vital skill, particularly when informative cues become occluded or degraded. Consequently, the acoustic environment requires flexible choosing and switching amongst available cues. The present study targets the brain functions underlying such changes in cue utilization. Participants performed a categorization task with immediate feedback on acoustic stimuli from two categories that varied in duration and spectral properties, while we simultaneously recorded Blood Oxygenation Level Dependent (BOLD) responses in fMRI and electroencephalograms (EEGs). In the first half of the experiment, categories could be best discriminated by spectral properties. Halfway through the experiment, spectral degradation rendered the stimulus duration the more informative cue. Behaviorally, degradation decreased the likelihood of utilizing spectral cues. Spectrally degrading the acoustic signal led to increased alpha power compared to nondegraded stimuli. The EEG-informed fMRI analyses revealed that alpha power correlated with BOLD changes in inferior parietal cortex and right posterior superior temporal gyrus (including planum temporale). In both areas, spectral degradation led to a weaker coupling of BOLD response to behavioral utilization of the spectral cue. These data provide converging evidence from behavioral modeling, electrophysiology, and hemodynamics that (a) increased alpha power mediates the inhibition of uninformative (here spectral) stimulus features, and that (b) the parietal attention network supports optimal cue utilization in auditory categorization. The results highlight the complex cortical processing of auditory categorization under realistic listening challenges. PMID:24926232

  13. Brain responses to altered auditory feedback during musical keyboard production: an fMRI study.

    PubMed

    Pfordresher, Peter Q; Mantell, James T; Brown, Steven; Zivadinov, Robert; Cox, Jennifer L

    2014-03-27

    Alterations of auditory feedback during piano performance can be profoundly disruptive. Furthermore, different alterations can yield different types of disruptive effects. Whereas alterations of feedback synchrony disrupt performed timing, alterations of feedback pitch contents can disrupt accuracy. The current research tested whether these behavioral dissociations correlate with differences in brain activity. Twenty pianists performed simple piano keyboard melodies while being scanned in a 3-T magnetic resonance imaging (MRI) scanner. In different conditions they experienced normal auditory feedback, altered auditory feedback (asynchronous delays or altered pitches), or control conditions that excluded movement or sound. Behavioral results replicated past findings. Neuroimaging data suggested that asynchronous delays led to increased activity in Broca's area and its right homologue, whereas disruptive alterations of pitch elevated activations in the cerebellum, area Spt, inferior parietal lobule, and the anterior cingulate cortex. Both disruptive conditions increased activations in the supplementary motor area. These results provide the first evidence of neural responses associated with perception/action mismatch during keyboard production. PMID:24513403

  14. Functional connectivity of dorsal and ventral frontoparietal seed regions during auditory orienting

    PubMed Central

    Rossi, Stephanie; Huang, Samantha; Furtak, Sharon C.; Belliveau, John W.; Ahveninen, Jyrki

    2014-01-01

    Our ability to refocus auditory attention is vital for even the most routine day-to-day activities. Shifts in auditory attention can be initiated "voluntarily", or triggered "involuntarily" by unexpected novel sound events. Here, we employed psychophysiological interaction (PPI) analyses of auditory functional MRI data, to compare functional connectivity patterns of distinct frontoparietal cortex regions during cued voluntary versus novelty-driven involuntary auditory attention shifting. Overall, our frontoparietal seed regions exhibited significant PPI increases with auditory cortex (AC) areas during both cued and novelty-driven orienting. However, significant positive PPI patterns associated with voluntary auditory attention (cue > novel task regressor), but mostly absent in analyses emphasizing involuntary orienting (novel > cue task regressor), were observed with seeds within the frontal eye fields (FEF), superior parietal lobule (SPL), and right supramarginal gyri (SMG). In contrast, significant positive PPIs associated selectively with involuntary orienting were observed between ACs and seeds within the bilateral anterior interior frontal gyri (IFG), and left posterior IFG, SMG, and posterior cingulate cortices (PCC). We also found indices of lateralization of different attention networks: PPI increases selective to voluntary attention occurred primarily with right-hemispheric regions, whereas those related to involuntary orienting were more frequent with left-hemisphere seeds. In conclusion, despite certain similarities in PPI patterns across conditions, the more dorsal aspects of right frontoparietal cortex demonstrated wider connectivity during cued/voluntary attention shifting, whereas certain left ventral frontoparietal seeds were more widely connected during novelty-triggered/involuntary orienting. Our findings provide partial support for distinct attention networks for voluntary and involuntary auditory attention. PMID:25128464

  15. A Trade-Off between Somatosensory and Auditory Related Brain Activity during Object Naming But Not Reading

    PubMed Central

    Hope, Thomas M.H.; Prejawa, Susan; Parker Jones, ‘Ōiwi; Vitkovitch, Melanie; Price, Cathy J.

    2015-01-01

    The parietal operculum, particularly the cytoarchitectonic area OP1 of the secondary somatosensory area (SII), is involved in somatosensory feedback. Using fMRI with 58 human subjects, we investigated task-dependent differences in SII/OP1 activity during three familiar speech production tasks: object naming, reading and repeatedly saying “1-2-3.” Bilateral SII/OP1 was significantly suppressed (relative to rest) during object naming, to a lesser extent when repeatedly saying “1-2-3” and not at all during reading. These results cannot be explained by task difficulty but the contrasting difference between naming and reading illustrates how the demands on somatosensory activity change with task, even when motor output (i.e., production of object names) is matched. To investigate what determined SII/OP1 deactivation during object naming, we searched the whole brain for areas where activity increased as that in SII/OP1 decreased. This across subject covariance analysis revealed a region in the right superior temporal sulcus (STS) that lies within the auditory cortex, and is activated by auditory feedback during speech production. The tradeoff between activity in SII/OP1 and STS was not observed during reading, which showed significantly more activation than naming in both SII/OP1 and STS bilaterally. These findings suggest that, although object naming is more error prone than reading, subjects can afford to rely more or less on somatosensory or auditory feedback during naming. In contrast, fast and efficient error-free reading places more consistent demands on both types of feedback, perhaps because of the potential for increased competition between lexical and sublexical codes at the articulatory level. PMID:25788691

  16. Evaluating auditory stream segregation of SAM tone sequences by subjective and objective psychoacoustical tasks, and brain activity

    PubMed Central

    Dolležal, Lena-Vanessa; Brechmann, André; Klump, Georg M.; Deike, Susann

    2014-01-01

    Auditory stream segregation refers to a segregated percept of signal streams with different acoustic features. Different approaches have been pursued in studies of stream segregation. In psychoacoustics, stream segregation has mostly been investigated with a subjective task asking the subjects to report their percept. Few studies have applied an objective task in which stream segregation is evaluated indirectly by determining thresholds for a percept that depends on whether auditory streams are segregated or not. Furthermore, both perceptual measures and physiological measures of brain activity have been employed but only little is known about their relation. How the results from different tasks and measures are related is evaluated in the present study using examples relying on the ABA- stimulation paradigm that apply the same stimuli. We presented A and B signals that were sinusoidally amplitude modulated (SAM) tones providing purely temporal, spectral or both types of cues to evaluate perceptual stream segregation and its physiological correlate. Which types of cues are most prominent was determined by the choice of carrier and modulation frequencies (fmod) of the signals. In the subjective task subjects reported their percept and in the objective task we measured their sensitivity for detecting time-shifts of B signals in an ABA- sequence. As a further measure of processes underlying stream segregation we employed functional magnetic resonance imaging (fMRI). SAM tone parameters were chosen to evoke an integrated (1-stream), a segregated (2-stream), or an ambiguous percept by adjusting the fmod difference between A and B tones (Δfmod). The results of both psychoacoustical tasks are significantly correlated. BOLD responses in fMRI depend on Δfmod between A and B SAM tones. The effect of Δfmod, however, differs between auditory cortex and frontal regions suggesting differences in representation related to the degree of perceptual ambiguity of the sequences

  17. Auditory pathways: are 'what' and 'where' appropriate?

    PubMed

    Hall, Deborah A

    2003-05-13

    New evidence confirms that the auditory system encompasses temporal, parietal and frontal brain regions, some of which partly overlap with the visual system. But common assumptions about the functional homologies between sensory systems may be misleading. PMID:12747854

  18. Auditory vocabulary of the right hemisphere following brain bisection or hemidecortication.

    PubMed

    Zaidel, E

    1976-09-01

    Unilateral scores of two commissurotomy and three (one left and two right) hemispherectomy patients were obtained on standardized auditory language comprehension tests which use pointing responses to a pictorial array. Unilateral performance by the commissurotomy patients was achieved by restricting the pictorial array to one visual half field, using a novel contact lens system which permits ocular scanning of the lateralized stimulus and self-monitoring of task performance. Using the Peabody and Ammons Picture Vocabulary Tests, the auditory vocabulary in the disconnected or isolated right hemispheres was found to be equivalent to that of normal subjects of ages 8:1 to 16:3 with a mean of 11:7 (eleven years and 7 months old). At the same time, standardized aphasia tests showed that the picture vocabulary in the right hemispheres is similar to that of a heterogeneous population of aphasics, even though the right hemispheres did not behave quite like any classical aphasic diagnostic group. No significant differences were found between right hemisphere comprehension of object vs. action names. Results indicated that vocabulary as a function of word frequency followed the same pattern in the right and left hemisphere although the right hemisphere was consistently lower. This parallel between the two hemispheres was conjectured to reflect some similar or even shared lexical structures in the two hemispheres. Together with other data on the performance of the right hemisphere on the Token Test (Zaidel, 1976), the results suggest a complex model of the development of language laterality in the brain, in which some, but not all, auditory language functions continue to develop in the right hemisphere past what is generally regarded as the critical period for language acquistion. In general, auditory language comprehension is better characterized as that of an "average aphasic" than that of a child of a specific age. PMID:1000988

  19. Age-related Changes in Auditory Nerve – Inner Hair Cell Connections, Hair Cell Numbers, Auditory Brain Stem Response and Gap Detection in UM-HET4 Mice

    PubMed Central

    Altschuler, RA; Dolan, DF; Halsey, K; Kanicki, A; Deng, N; Martin, C; Eberle, J; Kohrman, DC; Miller, RA; Schacht, J

    2015-01-01

    This study compared the timing of appearance of three components of age-related hearing loss that determine the pattern and severity of presbycusis: the functional and structural pathologies of sensory cells and neurons and changes in Gap Detection, the latter as an indicator of auditory temporal processing. Using UM-HET4 mice, genetically heterogeneous mice derived from four inbred strains, we studied the integrity of inner and outer hair cells by position along the cochlear spiral, inner hair cell-auditory nerve connections, spiral ganglion neurons, and determined auditory thresholds, as well as pre-pulse and gap inhibition of the acoustic startle reflex (ASR). Comparisons were made between mice of 5-7, 22-24 and 27-29 months of age. There was individual variability among mice in the onset and extent of age-related auditory pathology. At 22-24 months of age a moderate to large loss of outer hair cells was restricted to the apical third of the cochlea and threshold shifts in auditory brain stem response were minimal. There was also a large and significant loss of inner hair cell – auditory nerve connections and a significant reduction in Gap Detection. The expression of Ntf3 in the cochlea was significantly reduced. At 27-29 months of age there was no further change in the mean number of synaptic connections per inner hair cell or in gap detection, but a moderate to large loss of outer hair cells was found across all cochlear turns as well as significantly increased ABR threshold shifts at 4, 12, 24 and 48 kHz. A statistical analysis of correlations on an individual animal basis revealed that neither the hair cell loss nor the ABR threshold shifts correlated with loss of gap detection or with the loss of connections, consistent with independent pathological mechanisms. PMID:25665752

  20. Age-related changes in auditory nerve-inner hair cell connections, hair cell numbers, auditory brain stem response and gap detection in UM-HET4 mice.

    PubMed

    Altschuler, R A; Dolan, D F; Halsey, K; Kanicki, A; Deng, N; Martin, C; Eberle, J; Kohrman, D C; Miller, R A; Schacht, J

    2015-04-30

    This study compared the timing of appearance of three components of age-related hearing loss that determine the pattern and severity of presbycusis: the functional and structural pathologies of sensory cells and neurons and changes in gap detection (GD), the latter as an indicator of auditory temporal processing. Using UM-HET4 mice, genetically heterogeneous mice derived from four inbred strains, we studied the integrity of inner and outer hair cells by position along the cochlear spiral, inner hair cell-auditory nerve connections, spiral ganglion neurons (SGN), and determined auditory thresholds, as well as pre-pulse and gap inhibition of the acoustic startle reflex (ASR). Comparisons were made between mice of 5-7, 22-24 and 27-29 months of age. There was individual variability among mice in the onset and extent of age-related auditory pathology. At 22-24 months of age a moderate to large loss of outer hair cells was restricted to the apical third of the cochlea and threshold shifts in the auditory brain stem response were minimal. There was also a large and significant loss of inner hair cell-auditory nerve connections and a significant reduction in GD. The expression of Ntf3 in the cochlea was significantly reduced. At 27-29 months of age there was no further change in the mean number of synaptic connections per inner hair cell or in GD, but a moderate to large loss of outer hair cells was found across all cochlear turns as well as significantly increased ABR threshold shifts at 4, 12, 24 and 48 kHz. A statistical analysis of correlations on an individual animal basis revealed that neither the hair cell loss nor the ABR threshold shifts correlated with loss of GD or with the loss of connections, consistent with independent pathological mechanisms. PMID:25665752

  1. Case study: auditory brain responses in a minimally verbal child with autism and cerebral palsy

    PubMed Central

    Yau, Shu H.; McArthur, Genevieve; Badcock, Nicholas A.; Brock, Jon

    2015-01-01

    An estimated 30% of individuals with autism spectrum disorders (ASD) remain minimally verbal into late childhood, but research on cognition and brain function in ASD focuses almost exclusively on those with good or only moderately impaired language. Here we present a case study investigating auditory processing of GM, a nonverbal child with ASD and cerebral palsy. At the age of 8 years, GM was tested using magnetoencephalography (MEG) whilst passively listening to speech sounds and complex tones. Where typically developing children and verbal autistic children all demonstrated similar brain responses to speech and nonspeech sounds, GM produced much stronger responses to nonspeech than speech, particularly in the 65–165 ms (M50/M100) time window post-stimulus onset. GM was retested aged 10 years using electroencephalography (EEG) whilst passively listening to pure tone stimuli. Consistent with her MEG response to complex tones, GM showed an unusually early and strong response to pure tones in her EEG responses. The consistency of the MEG and EEG data in this single case study demonstrate both the potential and the feasibility of these methods in the study of minimally verbal children with ASD. Further research is required to determine whether GM's atypical auditory responses are characteristic of other minimally verbal children with ASD or of other individuals with cerebral palsy. PMID:26150768

  2. Cross-modal activation of auditory regions during visuo-spatial working memory in early deafness.

    PubMed

    Ding, Hao; Qin, Wen; Liang, Meng; Ming, Dong; Wan, Baikun; Li, Qiang; Yu, Chunshui

    2015-09-01

    Early deafness can reshape deprived auditory regions to enable the processing of signals from the remaining intact sensory modalities. Cross-modal activation has been observed in auditory regions during non-auditory tasks in early deaf subjects. In hearing subjects, visual working memory can evoke activation of the visual cortex, which further contributes to behavioural performance. In early deaf subjects, however, whether and how auditory regions participate in visual working memory remains unclear. We hypothesized that auditory regions may be involved in visual working memory processing and activation of auditory regions may contribute to the superior behavioural performance of early deaf subjects. In this study, 41 early deaf subjects (22 females and 19 males, age range: 20-26 years, age of onset of deafness < 2 years) and 40 age- and gender-matched hearing controls underwent functional magnetic resonance imaging during a visuo-spatial delayed recognition task that consisted of encoding, maintenance and recognition stages. The early deaf subjects exhibited faster reaction times on the spatial working memory task than did the hearing controls. Compared with hearing controls, deaf subjects exhibited increased activation in the superior temporal gyrus bilaterally during the recognition stage. This increased activation amplitude predicted faster and more accurate working memory performance in deaf subjects. Deaf subjects also had increased activation in the superior temporal gyrus bilaterally during the maintenance stage and in the right superior temporal gyrus during the encoding stage. These increased activation amplitude also predicted faster reaction times on the spatial working memory task in deaf subjects. These findings suggest that cross-modal plasticity occurs in auditory association areas in early deaf subjects. These areas are involved in visuo-spatial working memory. Furthermore, amplitudes of cross-modal activation during the maintenance stage were

  3. Electrical Brain Responses to an Auditory Illusion and the Impact of Musical Expertise

    PubMed Central

    Ioannou, Christos I.; Pereda, Ernesto; Lindsen, Job P.; Bhattacharya, Joydeep

    2015-01-01

    The presentation of two sinusoidal tones, one to each ear, with a slight frequency mismatch yields an auditory illusion of a beating frequency equal to the frequency difference between the two tones; this is known as binaural beat (BB). The effect of brief BB stimulation on scalp EEG is not conclusively demonstrated. Further, no studies have examined the impact of musical training associated with BB stimulation, yet musicians' brains are often associated with enhanced auditory processing. In this study, we analysed EEG brain responses from two groups, musicians and non-musicians, when stimulated by short presentation (1 min) of binaural beats with beat frequency varying from 1 Hz to 48 Hz. We focused our analysis on alpha and gamma band EEG signals, and they were analysed in terms of spectral power, and functional connectivity as measured by two phase synchrony based measures, phase locking value and phase lag index. Finally, these measures were used to characterize the degree of centrality, segregation and integration of the functional brain network. We found that beat frequencies belonging to alpha band produced the most significant steady-state responses across groups. Further, processing of low frequency (delta, theta, alpha) binaural beats had significant impact on cortical network patterns in the alpha band oscillations. Altogether these results provide a neurophysiological account of cortical responses to BB stimulation at varying frequencies, and demonstrate a modulation of cortico-cortical connectivity in musicians' brains, and further suggest a kind of neuronal entrainment of a linear and nonlinear relationship to the beating frequencies. PMID:26065708

  4. Auditory agnosia.

    PubMed

    Slevc, L Robert; Shell, Alison R

    2015-01-01

    Auditory agnosia refers to impairments in sound perception and identification despite intact hearing, cognitive functioning, and language abilities (reading, writing, and speaking). Auditory agnosia can be general, affecting all types of sound perception, or can be (relatively) specific to a particular domain. Verbal auditory agnosia (also known as (pure) word deafness) refers to deficits specific to speech processing, environmental sound agnosia refers to difficulties confined to non-speech environmental sounds, and amusia refers to deficits confined to music. These deficits can be apperceptive, affecting basic perceptual processes, or associative, affecting the relation of a perceived auditory object to its meaning. This chapter discusses what is known about the behavioral symptoms and lesion correlates of these different types of auditory agnosia (focusing especially on verbal auditory agnosia), evidence for the role of a rapid temporal processing deficit in some aspects of auditory agnosia, and the few attempts to treat the perceptual deficits associated with auditory agnosia. A clear picture of auditory agnosia has been slow to emerge, hampered by the considerable heterogeneity in behavioral deficits, associated brain damage, and variable assessments across cases. Despite this lack of clarity, these striking deficits in complex sound processing continue to inform our understanding of auditory perception and cognition. PMID:25726291

  5. Brain Region Mapping using Global Metabolomics

    PubMed Central

    Ivanisevic, Julijana; Epstein, Adrian; Kurczy, Michael E.; Benton, H. Paul; Uritboonthai, Winnie; Fox, Howard S.; Boska, Michael D.; Gendelman, Howard E.; Siuzdak, Gary

    2014-01-01

    SUMMARY Historically, studies of brain metabolism have been based on targeted analyses of a limited number of metabolites. Here we present a novel untargeted mass spectrometry-based metabolomics approach that has successfully uncovered differences in broad array of metabolites across anatomical regions of the mouse brain. The NSG immunodeficient mouse model was chosen because of its ability to undergo humanization leading to numerous applications in oncology and infectious disease research. Metabolic phenotyping by hydrophilic interaction liquid chromatography and nanostructure imaging mass spectrometry revealed unique water-soluble and lipid metabolite patterns between brain regions. Neurochemical differences in metabolic phenotypes were mainly defined by various phospholipids and several intriguing metabolites including carnosine, cholesterol sulfate, lipoamino acids, uric and sialic acid whose physiological roles in brain metabolism are poorly understood. This study lays important groundwork by defining regional homeostasis for the normal mouse brain to give context to the reaction to pathological events. PMID:25457182

  6. Alterations in regional homogeneity of resting-state brain activity in internet gaming addicts

    PubMed Central

    2012-01-01

    Backgrounds Internet gaming addiction (IGA), as a subtype of internet addiction disorder, is rapidly becoming a prevalent mental health concern around the world. The neurobiological underpinnings of IGA should be studied to unravel the potential heterogeneity of IGA. This study investigated the brain functions in IGA patients with resting-state fMRI. Methods Fifteen IGA subjects and fourteen healthy controls participated in this study. Regional homogeneity (ReHo) measures were used to detect the abnormal functional integrations. Results Comparing to the healthy controls, IGA subjects show enhanced ReHo in brainstem, inferior parietal lobule, left posterior cerebellum, and left middle frontal gyrus. All of these regions are thought related with sensory-motor coordination. In addition, IGA subjects show decreased ReHo in temporal, occipital and parietal brain regions. These regions are thought responsible for visual and auditory functions. Conclusions Our results suggest that long-time online game playing enhanced the brain synchronization in sensory-motor coordination related brain regions and decreased the excitability in visual and auditory related brain regions. PMID:22901705

  7. Brain-Generated Estradiol Drives Long-Term Optimization of Auditory Coding to Enhance the Discrimination of Communication Signals

    PubMed Central

    Tremere, Liisa A.; Pinaud, Raphael

    2011-01-01

    Auditory processing and hearing-related pathologies are heavily influenced by steroid hormones in a variety of vertebrate species including humans. The hormone estradiol has been recently shown to directly modulate the gain of central auditory neurons, in real-time, by controlling the strength of inhibitory transmission via a non-genomic mechanism. The functional relevance of this modulation, however, remains unknown. Here we show that estradiol generated in the songbird homologue of the mammalian auditory association cortex, rapidly enhances the effectiveness of the neural coding of complex, learned acoustic signals in awake zebra finches. Specifically, estradiol increases mutual information rates, coding efficiency and the neural discrimination of songs. These effects are mediated by estradiol’s modulation of both rate and temporal coding of auditory signals. Interference with the local action or production of estradiol in the auditory forebrain of freely-behaving animals disrupts behavioral responses to songs, but not to other behaviorally-relevant communication signals. Our findings directly show that estradiol is a key regulator of auditory function in the adult vertebrate brain. PMID:21368039

  8. A brain-computer interface controlled auditory event-related potential (p300) spelling system for locked-in patients.

    PubMed

    Kübler, Andrea; Furdea, Adrian; Halder, Sebastian; Hammer, Eva Maria; Nijboer, Femke; Kotchoubey, Boris

    2009-03-01

    Using brain-computer interfaces (BCI) humans can select letters or other targets on a computer screen without any muscular involvement. An intensively investigated kind of BCI is based on the recording of visual event-related brain potentials (ERP). However, some severely paralyzed patients who need a BCI for communication have impaired vision or lack control of gaze movement, thus making a BCI depending on visual input no longer feasible. In an effort to render the ERP-BCI usable for this group of patients, the ERP-BCI was adapted to auditory stimulation. Letters of the alphabet were assigned to cells in a 5 x 5 matrix. Rows of the matrix were coded with numbers 1 to 5, and columns with numbers 6 to 10, and the numbers were presented auditorily. To select a letter, users had to first select the row and then the column containing the desired letter. Four severely paralyzed patients in the end-stage of a neurodegenerative disease were examined. All patients performed above chance level. Spelling accuracy was significantly lower with the auditory system as compared with a similar visual system. Patients reported difficulties in concentrating on the task when presented with the auditory system. In future studies, the auditory ERP-BCI should be adjusted by taking into consideration specific features of severely paralyzed patients, such as reduced attention span. This adjustment in combination with more intensive training will show whether an auditory ERP-BCI can become an option for visually impaired patients. PMID:19351359

  9. Persistent frontal P300 brain potential suggests abnormal processing of auditory information in distractible children.

    PubMed

    Kilpeläinen, R; Luoma, L; Herrgård, E; Yppärilä, H; Partanen, J; Karhu, J

    1999-11-01

    The P300 event-related potential (ERP) was studied at the beginning, in the middle, and at the end of an auditory stimulus discrimination task in 70 normal 9-year-old children. Easily distractible children showed frontally a short-latency P300 response to target stimuli throughout the task, whereas in the non-distractible children the corresponding response was distinctly smaller and also showed a tendency to decrease in size towards the end of the task. The short-latency frontal P300 response reflects activation of the brain's orienting networks, and it normally decreases in size when stimuli lose their 'novelty value' with stimulus repetition. Persistent frontal P300 suggest that distractible children continued to show enhanced orienting to stimuli that should have already been well encoded and/or categorized. PMID:10599853

  10. Mature brain tissue in the sacrococcygeal region.

    PubMed

    Shrestha, Binod Bade; Ghimire, Pradeep; Ghartimagar, Dilasma; Jwarchan, Bishnu; Lalchan, Subita; Karmacharya, Mikesh

    2016-01-01

    Complete mature brain tissue in sacrococcygeal region is a rare congenital anomaly in a newborn, which usually is misdiagnosed for sacrococcygeal teratoma. Glial tumor-like ependymoma is also common in sacrococcygeal area but mostly appears later in life. We present a case of complete heterotopic brain tissue in the sacrococcygeal region. The patient underwent total excision of mass with coccygectomy. To our knowledge it is the second case being reported. PMID:27194682

  11. Mature brain tissue in the sacrococcygeal region

    PubMed Central

    Shrestha, Binod Bade; Ghimire, Pradeep; Ghartimagar, Dilasma; Jwarchan, Bishnu; Lalchan, Subita; Karmacharya, Mikesh

    2016-01-01

    Complete mature brain tissue in sacrococcygeal region is a rare congenital anomaly in a newborn, which usually is misdiagnosed for sacrococcygeal teratoma. Glial tumor-like ependymoma is also common in sacrococcygeal area but mostly appears later in life. We present a case of complete heterotopic brain tissue in the sacrococcygeal region. The patient underwent total excision of mass with coccygectomy. To our knowledge it is the second case being reported. PMID:27194682

  12. Frequency tuning of the dolphin's hearing as revealed by auditory brain-stem response with notch-noise masking.

    PubMed

    Popov, V V; Supin, A Y; Klishin, V O

    1997-12-01

    Notch-noise masking was used to measure frequency tuning in a dolphin (Tursiops truncatus) in a simultaneous-masking paradigm in conjunction with auditory brain-stem evoked potential recording. Measurements were made at probe frequencies of 64, 76, 90, and 108 kHz. The data were analyzed by fitting the rounded-exponent model of the auditory filters to the experimental data. The fitting parameter values corresponded to the filter tuning as follows: QER (center frequency divided by equivalent rectangular bandwidths) of 35 to 36.5 and Q10 dB of 18 to 19 at all tested frequencies. PMID:9407671

  13. [Topography of the Event-Related Brain Responses during Discrimination of Auditory Motion in Humans].

    PubMed

    Shestopalova, L B; Petropavlovskaia, E A; Vaitulevich, S Ph; Nikitin, N I

    2015-01-01

    The present study investigates the hemispheric asymmetry of auditory event-related potentials (ERPs) and mismatch negativity (MMN) during passive discrimination of the moving sound stimuli presented according to the oddball paradigm. The sound movement to the left/right from the head midline was produced by linear changes of the interaural time delay (ITD). It was found that the right-hemispheric N1 and P2 responses were more prominent than the left-hemispheric ones, especially in the fronto-lateral region. On the contrary, N250 and MMN responses demonstrated contralateral dominance in the fronto-lateral and fronto-medial regions. Direction of sound motion had no significant effect on the ERP or MMN topography. The right-hemispheric asymmetry of N1 increased with sound velocity. Maximal asymmetry of P2 was obtained with short stimulus trajectories. The contralateral bias of N250 and MMN increased with the spatial difference between standard and deviant stimuli. The results showed different type of hemispheric asymmetry for the early and late ERP components which could reflect the activity of distinct neural populations involved in the sensory and cognitive processing of the auditory input. PMID:26860001

  14. Evaluation of Auditory Brain Stems Evoked Response in Newborns With Pathologic Hyperbilirubinemia in Mashhad, Iran

    PubMed Central

    Okhravi, Tooba; Tarvij Eslami, Saeedeh; Hushyar Ahmadi, Ali; Nassirian, Hossain; Najibpour, Reza

    2015-01-01

    Background: Neonatal jaundice is a common cause of sensorneural hearing loss in children. Objectives: We aimed to detect the neurotoxic effects of pathologic hyperbilirubinemia on brain stem and auditory tract by auditory brain stem evoked response (ABR) which could predict early effects of hyperbilirubinemia. Patients and Methods: This case-control study was performed on newborns with pathologic hyperbilirubinemia. The inclusion criteria were healthy term and near term (35 - 37 weeks) newborns with pathologic hyperbilirubinemia with serum bilirubin values of ≥ 7 mg/dL, ≥ 10 mg/dL and ≥14 mg/dL at the first, second and third-day of life, respectively, and with bilirubin concentration ≥ 18 mg/dL at over 72 hours of life. The exclusion criteria included family history and diseases causing sensorineural hearing loss, use of auto-toxic medications within the preceding five days, convulsion, congenital craniofacial anomalies, birth trauma, preterm newborns < 35 weeks old, birth weight < 1500 g, asphyxia, and mechanical ventilations for five days or more. A total of 48 newborns with hyperbilirubinemia met the enrolment criteria as the case group and 49 healthy newborns as the control group, who were hospitalized in a university educational hospital (22 Bahaman), in a north-eastern city of Iran, Mashhad. ABR was performed on both groups. The evaluated variable factors were latency time, inter peak intervals time, and loss of waves. Results: The mean latencies of waves I, III and V of ABR were significantly higher in the pathologic hyperbilirubinemia group compared with the controls (P < 0.001). In addition, the mean interpeak intervals (IPI) of waves I-III, I-V and III-V of ABR were significantly higher in the pathologic hyperbilirubinemia group compared with the controls (P < 0.001). For example, the mean latencies time of wave I was significantly higher in right ear of the case group than in controls (2.16 ± 0.26 vs. 1.77 ± 0.15 milliseconds, respectively) (P

  15. Noninvasive brain stimulation for the treatment of auditory verbal hallucinations in schizophrenia: methods, effects and challenges

    PubMed Central

    Kubera, Katharina M.; Barth, Anja; Hirjak, Dusan; Thomann, Philipp A.; Wolf, Robert C.

    2015-01-01

    This mini-review focuses on noninvasive brain stimulation techniques as an augmentation method for the treatment of persistent auditory verbal hallucinations (AVH) in patients with schizophrenia. Paradigmatically, we place emphasis on transcranial magnetic stimulation (TMS). We specifically discuss rationales of stimulation and consider methodological questions together with issues of phenotypic diversity in individuals with drug-refractory and persistent AVH. Eventually, we provide a brief outlook for future investigations and treatment directions. Taken together, current evidence suggests TMS as a promising method in the treatment of AVH. Low-frequency stimulation of the superior temporal cortex (STC) may reduce symptom severity and frequency. Yet clinical effects are of relatively short duration and effect sizes appear to decrease over time along with publication of larger trials. Apart from considering other innovative stimulation techniques, such as transcranial Direct Current Stimulation (tDCS), and optimizing stimulation protocols, treatment of AVH using noninvasive brain stimulation will essentially rely on accurate identification of potential responders and non-responders for these treatment modalities. In this regard, future studies will need to consider distinct phenotypic presentations of AVH in patients with schizophrenia, together with the putative functional neurocircuitry underlying these phenotypes. PMID:26528145

  16. Hemispheric asymmetry of primary auditory cortex and Heschl’s gyrus in schizophrenia and nonpsychiatric brains

    PubMed Central

    Smiley, John F.; Hackett, Troy A.; Preuss, Todd M.; Bleiwas, Cynthia; Figarsky, Khadija; Mann, J. John; Rosoklija, Gorazd; Javitt, Daniel C.; Dwork, Andrew J.

    2013-01-01

    Heschl’s gyrus (HG) is reported to have a normal left>right hemispheric volume asymmetry, and reduced asymmetry in schizophrenia. Primary auditory cortex (A1) occupies the caudal-medial surface of HG, but it is unclear if A1 has normal asymmetry, or whether its asymmetry is altered in schizophrenia. To address these issues, we compared bilateral gray matter volumes of HG and A1, and neuron density and number in A1, in autopsy brains from male subjects with or without schizophrenia. Comparison of diagnostic groups did not reveal altered gray matter volumes, neuron density, neuron number or hemispheric asymmetries in schizophrenia. With respect to hemispheric differences, HG displayed a clear left>right asymmetry of gray matter volume. Area A1 occupied nearly half of HG, but had less consistent volume asymmetry, that was clearly present only in a subgroup of archival brains from elderly subjects. Neuron counts, in layers IIIb-c and V-VI, showed that the A1 volume asymmetry reflected differences in neuron number, and was not caused simply by changes in neuron density. Our findings confirm previous reports of striking hemispheric asymmetry of HG, and additionally show evidence that A1 has a corresponding asymmetry, although less consistent than that of HG. PMID:24148910

  17. Physiological modulators of Kv3.1 channels adjust firing patterns of auditory brain stem neurons.

    PubMed

    Brown, Maile R; El-Hassar, Lynda; Zhang, Yalan; Alvaro, Giuseppe; Large, Charles H; Kaczmarek, Leonard K

    2016-07-01

    Many rapidly firing neurons, including those in the medial nucleus of the trapezoid body (MNTB) in the auditory brain stem, express "high threshold" voltage-gated Kv3.1 potassium channels that activate only at positive potentials and are required for stimuli to generate rapid trains of actions potentials. We now describe the actions of two imidazolidinedione derivatives, AUT1 and AUT2, which modulate Kv3.1 channels. Using Chinese hamster ovary cells stably expressing rat Kv3.1 channels, we found that lower concentrations of these compounds shift the voltage of activation of Kv3.1 currents toward negative potentials, increasing currents evoked by depolarization from typical neuronal resting potentials. Single-channel recordings also showed that AUT1 shifted the open probability of Kv3.1 to more negative potentials. Higher concentrations of AUT2 also shifted inactivation to negative potentials. The effects of lower and higher concentrations could be mimicked in numerical simulations by increasing rates of activation and inactivation respectively, with no change in intrinsic voltage dependence. In brain slice recordings of mouse MNTB neurons, both AUT1 and AUT2 modulated firing rate at high rates of stimulation, a result predicted by numerical simulations. Our results suggest that pharmaceutical modulation of Kv3.1 currents represents a novel avenue for manipulation of neuronal excitability and has the potential for therapeutic benefit in the treatment of hearing disorders. PMID:27052580

  18. An online brain-computer interface based on shifting attention to concurrent streams of auditory stimuli

    NASA Astrophysics Data System (ADS)

    Hill, N. J.; Schölkopf, B.

    2012-04-01

    We report on the development and online testing of an electroencephalogram-based brain-computer interface (BCI) that aims to be usable by completely paralysed users—for whom visual or motor-system-based BCIs may not be suitable, and among whom reports of successful BCI use have so far been very rare. The current approach exploits covert shifts of attention to auditory stimuli in a dichotic-listening stimulus design. To compare the efficacy of event-related potentials (ERPs) and steady-state auditory evoked potentials (SSAEPs), the stimuli were designed such that they elicited both ERPs and SSAEPs simultaneously. Trial-by-trial feedback was provided online, based on subjects' modulation of N1 and P3 ERP components measured during single 5 s stimulation intervals. All 13 healthy subjects were able to use the BCI, with performance in a binary left/right choice task ranging from 75% to 96% correct across subjects (mean 85%). BCI classification was based on the contrast between stimuli in the attended stream and stimuli in the unattended stream, making use of every stimulus, rather than contrasting frequent standard and rare ‘oddball’ stimuli. SSAEPs were assessed offline: for all subjects, spectral components at the two exactly known modulation frequencies allowed discrimination of pre-stimulus from stimulus intervals, and of left-only stimuli from right-only stimuli when one side of the dichotic stimulus pair was muted. However, attention modulation of SSAEPs was not sufficient for single-trial BCI communication, even when the subject's attention was clearly focused well enough to allow classification of the same trials via ERPs. ERPs clearly provided a superior basis for BCI. The ERP results are a promising step towards the development of a simple-to-use, reliable yes/no communication system for users in the most severely paralysed states, as well as potential attention-monitoring and -training applications outside the context of assistive technology.

  19. Brain-derived neurotrophic factor modulates auditory function in the hearing cochlea.

    PubMed

    Sly, David J; Hampson, Amy J; Minter, Ricki L; Heffer, Leon F; Li, Jack; Millard, Rodney E; Winata, Leon; Niasari, Allen; O'Leary, Stephen J

    2012-02-01

    Neurotrophins prevent spiral ganglion neuron (SGN) degeneration in animal models of ototoxin-induced deafness and may be used in the future to improve the hearing of cochlear implant patients. It is increasingly common for patients with residual hearing to undergo cochlear implantation. However, the effect of neurotrophin treatment on acoustic hearing is not known. In this study, brain-derived neurotrophic factor (BDNF) was applied to the round window membrane of adult guinea pigs for 4 weeks using a cannula attached to a mini-osmotic pump. SGN survival was first assessed in ototoxically deafened guinea pigs to establish that the delivery method was effective. Increased survival of SGNs was observed in the basal and middle cochlear turns of deafened guinea pigs treated with BDNF, confirming that delivery to the cochlea was successful. The effects of BDNF treatment in animals with normal hearing were then assessed using distortion product otoacoustic emissions (DPOAEs), pure tone, and click-evoked auditory brainstem responses (ABRs). DPOAE assessment indicated a mild deficit of 5 dB SPL in treated and control groups at 1 and 4 weeks after cannula placement. In contrast, ABR evaluation showed that BDNF lowered thresholds at specific frequencies (8 and 16 kHz) after 1 and 4 weeks posttreatment when compared to the control cohort receiving Ringer's solution. Longer treatment for 4 weeks not only widened the range of frequencies ameliorated from 2 to 32 kHz but also lowered the threshold by at least 28 dB SPL at frequencies ≥16 kHz. BDNF treatment for 4 weeks also increased the amplitude of the ABR response when compared to either the control cohort or prior to treatment. We show that BDNF applied to the round window reduces auditory thresholds and could potentially be used clinically to protect residual hearing following cochlear implantation. PMID:22086147

  20. Delta, theta, beta, and gamma brain oscillations index levels of auditory sentence processing.

    PubMed

    Mai, Guangting; Minett, James W; Wang, William S-Y

    2016-06-01

    A growing number of studies indicate that multiple ranges of brain oscillations, especially the delta (δ, <4Hz), theta (θ, 4-8Hz), beta (β, 13-30Hz), and gamma (γ, 30-50Hz) bands, are engaged in speech and language processing. It is not clear, however, how these oscillations relate to functional processing at different linguistic hierarchical levels. Using scalp electroencephalography (EEG), the current study tested the hypothesis that phonological and the higher-level linguistic (semantic/syntactic) organizations during auditory sentence processing are indexed by distinct EEG signatures derived from the δ, θ, β, and γ oscillations. We analyzed specific EEG signatures while subjects listened to Mandarin speech stimuli in three different conditions in order to dissociate phonological and semantic/syntactic processing: (1) sentences comprising valid disyllabic words assembled in a valid syntactic structure (real-word condition); (2) utterances with morphologically valid syllables, but not constituting valid disyllabic words (pseudo-word condition); and (3) backward versions of the real-word and pseudo-word conditions. We tested four signatures: band power, EEG-acoustic entrainment (EAE), cross-frequency coupling (CFC), and inter-electrode renormalized partial directed coherence (rPDC). The results show significant effects of band power and EAE of δ and θ oscillations for phonological, rather than semantic/syntactic processing, indicating the importance of tracking δ- and θ-rate phonetic patterns during phonological analysis. We also found significant β-related effects, suggesting tracking of EEG to the acoustic stimulus (high-β EAE), memory processing (θ-low-β CFC), and auditory-motor interactions (20-Hz rPDC) during phonological analysis. For semantic/syntactic processing, we obtained a significant effect of γ power, suggesting lexical memory retrieval or processing grammatical word categories. Based on these findings, we confirm that scalp EEG

  1. Maps of the Auditory Cortex.

    PubMed

    Brewer, Alyssa A; Barton, Brian

    2016-07-01

    One of the fundamental properties of the mammalian brain is that sensory regions of cortex are formed of multiple, functionally specialized cortical field maps (CFMs). Each CFM comprises two orthogonal topographical representations, reflecting two essential aspects of sensory space. In auditory cortex, auditory field maps (AFMs) are defined by the combination of tonotopic gradients, representing the spectral aspects of sound (i.e., tones), with orthogonal periodotopic gradients, representing the temporal aspects of sound (i.e., period or temporal envelope). Converging evidence from cytoarchitectural and neuroimaging measurements underlies the definition of 11 AFMs across core and belt regions of human auditory cortex, with likely homology to those of macaque. On a macrostructural level, AFMs are grouped into cloverleaf clusters, an organizational structure also seen in visual cortex. Future research can now use these AFMs to investigate specific stages of auditory processing, key for understanding behaviors such as speech perception and multimodal sensory integration. PMID:27145914

  2. Touch activates human auditory cortex.

    PubMed

    Schürmann, Martin; Caetano, Gina; Hlushchuk, Yevhen; Jousmäki, Veikko; Hari, Riitta

    2006-05-01

    Vibrotactile stimuli can facilitate hearing, both in hearing-impaired and in normally hearing people. Accordingly, the sounds of hands exploring a surface contribute to the explorer's haptic percepts. As a possible brain basis of such phenomena, functional brain imaging has identified activations specific to audiotactile interaction in secondary somatosensory cortex, auditory belt area, and posterior parietal cortex, depending on the quality and relative salience of the stimuli. We studied 13 subjects with non-invasive functional magnetic resonance imaging (fMRI) to search for auditory brain areas that would be activated by touch. Vibration bursts of 200 Hz were delivered to the subjects' fingers and palm and tactile pressure pulses to their fingertips. Noise bursts served to identify auditory cortex. Vibrotactile-auditory co-activation, addressed with minimal smoothing to obtain a conservative estimate, was found in an 85-mm3 region in the posterior auditory belt area. This co-activation could be related to facilitated hearing at the behavioral level, reflecting the analysis of sound-like temporal patterns in vibration. However, even tactile pulses (without any vibration) activated parts of the posterior auditory belt area, which therefore might subserve processing of audiotactile events that arise during dynamic contact between hands and environment. PMID:16488157

  3. Auditory spatial processing in Alzheimer's disease.

    PubMed

    Golden, Hannah L; Nicholas, Jennifer M; Yong, Keir X X; Downey, Laura E; Schott, Jonathan M; Mummery, Catherine J; Crutch, Sebastian J; Warren, Jason D

    2015-01-01

    The location and motion of sounds in space are important cues for encoding the auditory world. Spatial processing is a core component of auditory scene analysis, a cognitively demanding function that is vulnerable in Alzheimer's disease. Here we designed a novel neuropsychological battery based on a virtual space paradigm to assess auditory spatial processing in patient cohorts with clinically typical Alzheimer's disease (n = 20) and its major variant syndrome, posterior cortical atrophy (n = 12) in relation to healthy older controls (n = 26). We assessed three dimensions of auditory spatial function: externalized versus non-externalized sound discrimination, moving versus stationary sound discrimination and stationary auditory spatial position discrimination, together with non-spatial auditory and visual spatial control tasks. Neuroanatomical correlates of auditory spatial processing were assessed using voxel-based morphometry. Relative to healthy older controls, both patient groups exhibited impairments in detection of auditory motion, and stationary sound position discrimination. The posterior cortical atrophy group showed greater impairment for auditory motion processing and the processing of a non-spatial control complex auditory property (timbre) than the typical Alzheimer's disease group. Voxel-based morphometry in the patient cohort revealed grey matter correlates of auditory motion detection and spatial position discrimination in right inferior parietal cortex and precuneus, respectively. These findings delineate auditory spatial processing deficits in typical and posterior Alzheimer's disease phenotypes that are related to posterior cortical regions involved in both syndromic variants and modulated by the syndromic profile of brain degeneration. Auditory spatial deficits contribute to impaired spatial awareness in Alzheimer's disease and may constitute a novel perceptual model for probing brain network disintegration across the Alzheimer's disease

  4. Auditory evoked potentials to spectro-temporal modulation of complex tones in normal subjects and patients with severe brain injury.

    PubMed

    Jones, S J; Vaz Pato, M; Sprague, L; Stokes, M; Munday, R; Haque, N

    2000-05-01

    In order to assess higher auditory processing capabilities, long-latency auditory evoked potentials (AEPs) were recorded to synthesized musical instrument tones in 22 post-comatose patients with severe brain injury causing variably attenuated behavioural responsiveness. On the basis of normative studies, three different types of spectro-temporal modulation were employed. When a continuous 'clarinet' tone changes pitch once every few seconds, N1/P2 potentials are evoked at latencies of approximately 90 and 180 ms, respectively. Their distribution in the fronto-central region is consistent with generators in the supratemporal cortex of both hemispheres. When the pitch is modulated at a much faster rate ( approximately 16 changes/s), responses to each change are virtually abolished but potentials with similar distribution are still elicited by changing the timbre (e.g. 'clarinet' to 'oboe') every few seconds. These responses appear to represent the cortical processes concerned with spectral pattern analysis and the grouping of frequency components to form sound 'objects'. Following a period of 16/s oscillation between two pitches, a more anteriorly distributed negativity is evoked on resumption of a steady pitch. Various lines of evidence suggest that this is probably equivalent to the 'mismatch negativity' (MMN), reflecting a pre-perceptual, memory-based process for detection of change in spectro-temporal sound patterns. This method requires no off-line subtraction of AEPs evoked by the onset of a tone, and the MMN is produced rapidly and robustly with considerably larger amplitude (usually >5 microV) than that to discontinuous pure tones. In the brain-injured patients, the presence of AEPs to two or more complex tone stimuli (in the combined assessment of two authors who were 'blind' to the clinical and behavioural data) was significantly associated with the demonstrable possession of discriminative hearing (the ability to respond differentially to verbal commands

  5. Causal contribution of primate auditory cortex to auditory perceptual decision-making

    PubMed Central

    Tsunada, Joji; Liu, Andrew S.K.; Gold, Joshua I.; Cohen, Yale E.

    2015-01-01

    Auditory perceptual decisions are thought to be mediated by the ventral auditory pathway. However, the specific and causal contributions of different brain regions in this pathway, including the middle-lateral (ML) and anterolateral (AL) belt regions of the auditory cortex, to auditory decisions have not been fully identified. To identify these contributions, we recorded from and microstimulated ML and AL sites while monkeys decided whether an auditory stimulus contained more low-frequency or high-frequency tone bursts. Both ML and AL neural activity was modulated by the frequency content of the stimulus. However, only the responses of the most stimulus-sensitive AL neurons were systematically modulated by the monkeys’ choices. Consistent with this observation, microstimulation of AL—but not ML—systematically biased the monkeys’ behavior toward the choice associated with the preferred frequency of the stimulated site. Together, these findings suggest that AL directly and causally contributes sensory evidence used to form this auditory decision. PMID:26656644

  6. Diagnostic System Based on the Human AUDITORY-BRAIN Model for Measuring Environmental NOISE—AN Application to Railway Noise

    NASA Astrophysics Data System (ADS)

    SAKAI, H.; HOTEHAMA, T.; ANDO, Y.; PRODI, N.; POMPOLI, R.

    2002-02-01

    Measurements of railway noise were conducted by use of a diagnostic system of regional environmental noise. The system is based on the model of the human auditory-brain system. The model consists of the interplay of autocorrelators and an interaural crosscorrelator acting on the pressure signals arriving at the ear entrances, and takes into account the specialization of left and right human cerebral hemispheres. Different kinds of railway noise were measured through binaural microphones of a dummy head. To characterize the railway noise, physical factors, extracted from the autocorrelation functions (ACF) and interaural crosscorrelation function (IACF) of binaural signals, were used. The factors extracted from ACF were (1) energy represented at the origin of the delay, Φ (0), (2) effective duration of the envelope of the normalized ACF, τe, (3) the delay time of the first peak, τ1, and (4) its amplitude,ø1 . The factors extracted from IACF were (5) IACC, (6) interaural delay time at which the IACC is defined, τIACC, and (7) width of the IACF at the τIACC,WIACC . The factor Φ (0) can be represented as a geometrical mean of energies at both ears as listening level, LL.

  7. Simultaneous recording of fluorescence and electrical signals by photometric patch electrode in deep brain regions in vivo.

    PubMed

    Hirai, Yasuharu; Nishino, Eri; Ohmori, Harunori

    2015-06-01

    Despite its widespread use, high-resolution imaging with multiphoton microscopy to record neuronal signals in vivo is limited to the surface of brain tissue because of limited light penetration. Moreover, most imaging studies do not simultaneously record electrical neural activity, which is, however, crucial to understanding brain function. Accordingly, we developed a photometric patch electrode (PME) to overcome the depth limitation of optical measurements and also enable the simultaneous recording of neural electrical responses in deep brain regions. The PME recoding system uses a patch electrode to excite a fluorescent dye and to measure the fluorescence signal as a light guide, to record electrical signal, and to apply chemicals to the recorded cells locally. The optical signal was analyzed by either a spectrometer of high light sensitivity or a photomultiplier tube depending on the kinetics of the responses. We used the PME in Oregon Green BAPTA-1 AM-loaded avian auditory nuclei in vivo to monitor calcium signals and electrical responses. We demonstrated distinct response patterns in three different nuclei of the ascending auditory pathway. On acoustic stimulation, a robust calcium fluorescence response occurred in auditory cortex (field L) neurons that outlasted the electrical response. In the auditory midbrain (inferior colliculus), both responses were transient. In the brain-stem cochlear nucleus magnocellularis, calcium response seemed to be effectively suppressed by the activity of metabotropic glutamate receptors. In conclusion, the PME provides a powerful tool to study brain function in vivo at a tissue depth inaccessible to conventional imaging devices. PMID:25761950

  8. Simultaneous recording of fluorescence and electrical signals by photometric patch electrode in deep brain regions in vivo

    PubMed Central

    Hirai, Yasuharu; Nishino, Eri

    2015-01-01

    Despite its widespread use, high-resolution imaging with multiphoton microscopy to record neuronal signals in vivo is limited to the surface of brain tissue because of limited light penetration. Moreover, most imaging studies do not simultaneously record electrical neural activity, which is, however, crucial to understanding brain function. Accordingly, we developed a photometric patch electrode (PME) to overcome the depth limitation of optical measurements and also enable the simultaneous recording of neural electrical responses in deep brain regions. The PME recoding system uses a patch electrode to excite a fluorescent dye and to measure the fluorescence signal as a light guide, to record electrical signal, and to apply chemicals to the recorded cells locally. The optical signal was analyzed by either a spectrometer of high light sensitivity or a photomultiplier tube depending on the kinetics of the responses. We used the PME in Oregon Green BAPTA-1 AM-loaded avian auditory nuclei in vivo to monitor calcium signals and electrical responses. We demonstrated distinct response patterns in three different nuclei of the ascending auditory pathway. On acoustic stimulation, a robust calcium fluorescence response occurred in auditory cortex (field L) neurons that outlasted the electrical response. In the auditory midbrain (inferior colliculus), both responses were transient. In the brain-stem cochlear nucleus magnocellularis, calcium response seemed to be effectively suppressed by the activity of metabotropic glutamate receptors. In conclusion, the PME provides a powerful tool to study brain function in vivo at a tissue depth inaccessible to conventional imaging devices. PMID:25761950

  9. Hyperpolarization-independent maturation and refinement of GABA/glycinergic connections in the auditory brain stem.

    PubMed

    Lee, Hanmi; Bach, Eva; Noh, Jihyun; Delpire, Eric; Kandler, Karl

    2016-03-01

    During development GABA and glycine synapses are initially excitatory before they gradually become inhibitory. This transition is due to a developmental increase in the activity of neuronal potassium-chloride cotransporter 2 (KCC2), which shifts the chloride equilibrium potential (ECl) to values more negative than the resting membrane potential. While the role of early GABA and glycine depolarizations in neuronal development has become increasingly clear, the role of the transition to hyperpolarization in synapse maturation and circuit refinement has remained an open question. Here we investigated this question by examining the maturation and developmental refinement of GABA/glycinergic and glutamatergic synapses in the lateral superior olive (LSO), a binaural auditory brain stem nucleus, in KCC2-knockdown mice, in which GABA and glycine remain depolarizing. We found that many key events in the development of synaptic inputs to the LSO, such as changes in neurotransmitter phenotype, strengthening and elimination of GABA/glycinergic connection, and maturation of glutamatergic synapses, occur undisturbed in KCC2-knockdown mice compared with wild-type mice. These results indicate that maturation of inhibitory and excitatory synapses in the LSO is independent of the GABA and glycine depolarization-to-hyperpolarization transition. PMID:26655825

  10. Non-invasive Brain Stimulation and Auditory Verbal Hallucinations: New Techniques and Future Directions

    PubMed Central

    Moseley, Peter; Alderson-Day, Ben; Ellison, Amanda; Jardri, Renaud; Fernyhough, Charles

    2016-01-01

    Auditory verbal hallucinations (AVHs) are the experience of hearing a voice in the absence of any speaker. Results from recent attempts to treat AVHs with neurostimulation (rTMS or tDCS) to the left temporoparietal junction have not been conclusive, but suggest that it may be a promising treatment option for some individuals. Some evidence suggests that the therapeutic effect of neurostimulation on AVHs may result from modulation of cortical areas involved in the ability to monitor the source of self-generated information. Here, we provide a brief overview of cognitive models and neurostimulation paradigms associated with treatment of AVHs, and discuss techniques that could be explored in the future to improve the efficacy of treatment, including alternating current and random noise stimulation. Technical issues surrounding the use of neurostimulation as a treatment option are discussed (including methods to localize the targeted cortical area, and the state-dependent effects of brain stimulation), as are issues surrounding the acceptability of neurostimulation for adolescent populations and individuals who experience qualitatively different types of AVH. PMID:26834541

  11. Brain electrical activity evoked by mental formation of auditory expectations and images.

    PubMed

    Janata, P

    2001-01-01

    Evidence for the brain's derivation of explicit expectancies in an ongoing sensory context has been well established by studies of the P300 and processing negativity (PN) components of the event-related potential (ERP). "Emitted potentials" generated in the absence of sensory input by unexpected stimulus omissions also exhibit a P300 component and provide another perspective on patterns of brain activity related to the processing of expectancies. The studies described herein extend earlier emitted potential findings in several aspects. First, high-density (128-channel) EEG recordings are used for topographical mapping of emitted potentials. Second, the primary focus is on emitted potential components preceding the P300, i.e. those components that are more likely to resemble ERP components associated with sensory processing. Third, the dependence of emitted potentials on attention is assessed. Fourth, subjects' knowledge of the structure of an auditory stimulus sequence is modulated so that emitted potentials can be compared between conditions that are identical in physical aspects but differ in terms of subjects' expectations regarding the sequence structure. Finally, a novel task is used to elicit emitted potentials, in which subjects explicitly imagine the continuations of simple melodies. In this task, subjects mentally complete melodic fragments in the appropriate tempo, even though they know with absolute certainty that no sensory stimulus will occur. Emitted potentials were elicited only when subjects actively formed expectations or images. The topographies of the initial portion of the emitted potentials were significantly correlated with the N100 topography elicited by corresponding acoustic stimuli, but uncorrelated with the topographies of corresponding silence control periods. PMID:11302397

  12. fMRI reveals lateralized pattern of brain activity modulated by the metrics of stimuli during auditory rhyme processing.

    PubMed

    Hurschler, Martina A; Liem, Franziskus; Oechslin, Mathias; Stämpfli, Philipp; Meyer, Martin

    2015-08-01

    Our fMRI study investigates auditory rhyme processing in spoken language to further elucidate the topic of functional lateralization of language processing. During scanning, 14 subjects listened to four different types of versed word strings and subsequently performed either a rhyme or a meter detection task. Our results show lateralization to auditory-related temporal regions in the right hemisphere irrespective of task. As for the left hemisphere we report responses in the supramarginal gyrus as well as in the opercular part of the inferior frontal gyrus modulated by the presence of regular meter and rhyme. The interaction of rhyme and meter was associated with increased involvement of the superior temporal sulcus and the putamen of the right hemisphere. Overall, these findings support the notion of right-hemispheric specialization for suprasegmental analyses during processing of spoken sentences and provide neuroimaging evidence for the influence of metrics on auditory rhyme processing. PMID:26025759

  13. Mother’s voice and heartbeat sounds elicit auditory plasticity in the human brain before full gestation

    PubMed Central

    Webb, Alexandra R.; Heller, Howard T.; Benson, Carol B.; Lahav, Amir

    2015-01-01

    Brain development is largely shaped by early sensory experience. However, it is currently unknown whether, how early, and to what extent the newborn’s brain is shaped by exposure to maternal sounds when the brain is most sensitive to early life programming. The present study examined this question in 40 infants born extremely prematurely (between 25- and 32-wk gestation) in the first month of life. Newborns were randomized to receive auditory enrichment in the form of audio recordings of maternal sounds (including their mother’s voice and heartbeat) or routine exposure to hospital environmental noise. The groups were otherwise medically and demographically comparable. Cranial ultrasonography measurements were obtained at 30 ± 3 d of life. Results show that newborns exposed to maternal sounds had a significantly larger auditory cortex (AC) bilaterally compared with control newborns receiving standard care. The magnitude of the right and left AC thickness was significantly correlated with gestational age but not with the duration of sound exposure. Measurements of head circumference and the widths of the frontal horn (FH) and the corpus callosum (CC) were not significantly different between the two groups. This study provides evidence for experience-dependent plasticity in the primary AC before the brain has reached full-term maturation. Our results demonstrate that despite the immaturity of the auditory pathways, the AC is more adaptive to maternal sounds than environmental noise. Further studies are needed to better understand the neural processes underlying this early brain plasticity and its functional implications for future hearing and language development. PMID:25713382

  14. Brain-computer interfaces using capacitive measurement of visual or auditory steady-state responses

    NASA Astrophysics Data System (ADS)

    Baek, Hyun Jae; Kim, Hyun Seok; Heo, Jeong; Lim, Yong Gyu; Park, Kwang Suk

    2013-04-01

    Objective. Brain-computer interface (BCI) technologies have been intensely studied to provide alternative communication tools entirely independent of neuromuscular activities. Current BCI technologies use electroencephalogram (EEG) acquisition methods that require unpleasant gel injections, impractical preparations and clean-up procedures. The next generation of BCI technologies requires practical, user-friendly, nonintrusive EEG platforms in order to facilitate the application of laboratory work in real-world settings. Approach. A capacitive electrode that does not require an electrolytic gel or direct electrode-scalp contact is a potential alternative to the conventional wet electrode in future BCI systems. We have proposed a new capacitive EEG electrode that contains a conductive polymer-sensing surface, which enhances electrode performance. This paper presents results from five subjects who exhibited visual or auditory steady-state responses according to BCI using these new capacitive electrodes. The steady-state visual evoked potential (SSVEP) spelling system and the auditory steady-state response (ASSR) binary decision system were employed. Main results. Offline tests demonstrated BCI performance high enough to be used in a BCI system (accuracy: 95.2%, ITR: 19.91 bpm for SSVEP BCI (6 s), accuracy: 82.6%, ITR: 1.48 bpm for ASSR BCI (14 s)) with the analysis time being slightly longer than that when wet electrodes were employed with the same BCI system (accuracy: 91.2%, ITR: 25.79 bpm for SSVEP BCI (4 s), accuracy: 81.3%, ITR: 1.57 bpm for ASSR BCI (12 s)). Subjects performed online BCI under the SSVEP paradigm in copy spelling mode and under the ASSR paradigm in selective attention mode with a mean information transfer rate (ITR) of 17.78 ± 2.08 and 0.7 ± 0.24 bpm, respectively. Significance. The results of these experiments demonstrate the feasibility of using our capacitive EEG electrode in BCI systems. This capacitive electrode may become a flexible and

  15. Repetition suppression and repetition enhancement underlie auditory memory-trace formation in the human brain: an MEG study.

    PubMed

    Recasens, Marc; Leung, Sumie; Grimm, Sabine; Nowak, Rafal; Escera, Carles

    2015-03-01

    The formation of echoic memory traces has traditionally been inferred from the enhanced responses to its deviations. The mismatch negativity (MMN), an auditory event-related potential (ERP) elicited between 100 and 250ms after sound deviation is an indirect index of regularity encoding that reflects a memory-based comparison process. Recently, repetition positivity (RP) has been described as a candidate ERP correlate of direct memory trace formation. RP consists of repetition suppression and enhancement effects occurring in different auditory components between 50 and 250ms after sound onset. However, the neuronal generators engaged in the encoding of repeated stimulus features have received little interest. This study intends to investigate the neuronal sources underlying the formation and strengthening of new memory traces by employing a roving-standard paradigm, where trains of different frequencies and different lengths are presented randomly. Source generators of repetition enhanced (RE) and suppressed (RS) activity were modeled using magnetoencephalography (MEG) in healthy subjects. Our results show that, in line with RP findings, N1m (~95-150ms) activity is suppressed with stimulus repetition. In addition, we observed the emergence of a sustained field (~230-270ms) that showed RE. Source analysis revealed neuronal generators of RS and RE located in both auditory and non-auditory areas, like the medial parietal cortex and frontal areas. The different timing and location of neural generators involved in RS and RE points to the existence of functionally separated mechanisms devoted to acoustic memory-trace formation in different auditory processing stages of the human brain. PMID:25528656

  16. Brain functional connectivity during the experience of thought blocks in schizophrenic patients with persistent auditory verbal hallucinations: an EEG study.

    PubMed

    Angelopoulos, Elias; Koutsoukos, Elias; Maillis, Antonis; Papadimitriou, George N; Stefanis, Costas

    2014-03-01

    Thought blocks (TBs) are characterized by regular interruptions in the stream of thought. Outward signs are abrupt and repeated interruptions in the flow of conversation or actions while subjective experience is that of a total and uncontrollable emptying of the mind. In the very limited bibliography regarding TB, the phenomenon is thought to be conceptualized as a disturbance of consciousness that can be attributed to stoppages of continuous information processing due to an increase in the volume of information to be processed. In an attempt to investigate potential expression of the phenomenon on the functional properties of electroencephalographic (EEG) activity, an EEG study was contacted in schizophrenic patients with persisting auditory verbal hallucinations (AVHs) who additionally exhibited TBs. In this case, we hypothesized that the persistent and dense AVHs could serve the role of an increased information flow that the brain is unable to process, a condition that is perceived by the person as TB. Phase synchronization analyses performed on EEG segments during the experience of TBs showed that synchrony values exhibited a long-range common mode of coupling (grouped behavior) among the left temporal area and the remaining central and frontal brain areas. These common synchrony-fluctuation schemes were observed for 0.5 to 2s and were detected in a 4-s window following the estimated initiation of the phenomenon. The observation was frequency specific and detected in the broad alpha band region (6-12Hz). The introduction of synchrony entropy (SE) analysis applied on the cumulative synchrony distribution showed that TB states were characterized by an explicit preference of the system to be functioned at low values of synchrony, while the synchrony values are broadly distributed during the recovery state. Our results indicate that during TB states, the phase locking of several brain areas were converged uniformly in a narrow band of low synchrony values and in a

  17. Recognition of regions in brain sections.

    PubMed

    Waks, A; Tretiak, O J

    1990-01-01

    This paper addresses the problem of region identification in sequential brain sections and presents a recognition system that finds and tracks region boundaries in those sections. The characteristics of the areas of interest are unique in one sense because they are not stationary. Some regions are hardly discernible. In others, parts of the boundary are missing or so completely blurred that parts of the background may be considered as an extension of the region itself. Moreover, outliers are likely to exist in many cases. Due to the unique properties of brain regions, the emphasis is on robustification and efficiency. The region segmentation problem was expressed as a multi-hypothesis test seeking boundaries that maximize a performance criterion which is general in terms of blur and noise. Boundary candidates are restricted to an adaptive search area around a reference boundary which is usually the outcome of the algorithm from the previous section. The search for the maximum criterion uses a fast first order dynamic programing (DP) procedure, reducing the processing time. Outlier rejection techniques are integrated with the multi-hypothesis test to compensate for both outliers and noise. The result is the reference for the next section. Experimental results on boundary detection are presented. The algorithm is successful in tracing boundaries when the contrast is smaller than the noise power, and when parts of the outlines are missing. PMID:2224832

  18. On the temporal window of auditory-brain system in connection with subjective responses

    NASA Astrophysics Data System (ADS)

    Mouri, Kiminori

    2003-08-01

    The human auditory-brain system processes information extracted from autocorrelation function (ACF) of the source signal and interaural cross correlation function (IACF) of binaural sound signals which are associated with the left and right cerebral hemispheres, respectively. The purpose of this dissertation is to determine the desirable temporal window (2T: integration interval) for ACF and IACF mechanisms. For the ACF mechanism, the visual change of Φ(0), i.e., the power of ACF, was associated with the change of loudness, and it is shown that the recommended temporal window is given as about 30(τe)min [s]. The value of (τe)min is the minimum value of effective duration of the running ACF of the source signal. It is worth noticing from the experiment of EEG that the most preferred delay time of the first reflection sound is determined by the piece indicating (τe)min in the source signal. For the IACF mechanism, the temporal window is determined as below: The measured range of τIACC corresponding to subjective angle for the moving image sound depends on the temporal window. Here, the moving image was simulated by the use of two loudspeakers located at +/-20° in the horizontal plane, reproducing amplitude modulated band-limited noise alternatively. It is found that the temporal window has a wide range of values from 0.03 to 1 [s] for the modulation frequency below 0.2 Hz. Thesis advisor: Yoichi Ando Copies of this thesis written in English can be obtained from Kiminori Mouri, 5-3-3-1110 Harayama-dai, Sakai city, Osaka 590-0132, Japan. E-mail address: km529756@aol.com

  19. Regional brain responses in nulliparous women to emotional infant stimuli.

    PubMed

    Montoya, Jessica L; Landi, Nicole; Kober, Hedy; Worhunsky, Patrick D; Rutherford, Helena J V; Mencl, W Einar; Mayes, Linda C; Potenza, Marc N

    2012-01-01

    Infant cries and facial expressions influence social interactions and elicit caretaking behaviors from adults. Recent neuroimaging studies suggest that neural responses to infant stimuli involve brain regions that process rewards. However, these studies have yet to investigate individual differences in tendencies to engage or withdraw from motivationally relevant stimuli. To investigate this, we used event-related fMRI to scan 17 nulliparous women. Participants were presented with novel infant cries of two distress levels (low and high) and unknown infant faces of varying affect (happy, sad, and neutral) in a randomized, counter-balanced order. Brain activation was subsequently correlated with scores on the Behavioral Inhibition System/Behavioral Activation System scale. Infant cries activated bilateral superior and middle temporal gyri (STG and MTG) and precentral and postcentral gyri. Activation was greater in bilateral temporal cortices for low- relative to high-distress cries. Happy relative to neutral faces activated the ventral striatum, caudate, ventromedial prefrontal, and orbitofrontal cortices. Sad versus neutral faces activated the precuneus, cuneus, and posterior cingulate cortex, and behavioral activation drive correlated with occipital cortical activations in this contrast. Behavioral inhibition correlated with activation in the right STG for high- and low-distress cries relative to pink noise. Behavioral drive correlated inversely with putamen, caudate, and thalamic activations for the comparison of high-distress cries to pink noise. Reward-responsiveness correlated with activation in the left precentral gyrus during the perception of low-distress cries relative to pink noise. Our findings indicate that infant cry stimuli elicit activations in areas implicated in auditory processing and social cognition. Happy infant faces may be encoded as rewarding, whereas sad faces activate regions associated with empathic processing. Differences in motivational

  20. Effects of Aging and Adult-Onset Hearing Loss on Cortical Auditory Regions

    PubMed Central

    Cardin, Velia

    2016-01-01

    Hearing loss is a common feature in human aging. It has been argued that dysfunctions in central processing are important contributing factors to hearing loss during older age. Aging also has well documented consequences for neural structure and function, but it is not clear how these effects interact with those that arise as a consequence of hearing loss. This paper reviews the effects of aging and adult-onset hearing loss in the structure and function of cortical auditory regions. The evidence reviewed suggests that aging and hearing loss result in atrophy of cortical auditory regions and stronger engagement of networks involved in the detection of salient events, adaptive control and re-allocation of attention. These cortical mechanisms are engaged during listening in effortful conditions in normal hearing individuals. Therefore, as a consequence of aging and hearing loss, all listening becomes effortful and cognitive load is constantly high, reducing the amount of available cognitive resources. This constant effortful listening and reduced cognitive spare capacity could be what accelerates cognitive decline in older adults with hearing loss. PMID:27242405

  1. Task-dependent modulation of regions in the left temporal cortex during auditory sentence comprehension.

    PubMed

    Zhang, Linjun; Yue, Qiuhai; Zhang, Yang; Shu, Hua; Li, Ping

    2015-01-01

    Numerous studies have revealed the essential role of the left lateral temporal cortex in auditory sentence comprehension along with evidence of the functional specialization of the anterior and posterior temporal sub-areas. However, it is unclear whether task demands (e.g., active vs. passive listening) modulate the functional specificity of these sub-areas. In the present functional magnetic resonance imaging (fMRI) study, we addressed this issue by applying both independent component analysis (ICA) and general linear model (GLM) methods. Consistent with previous studies, intelligible sentences elicited greater activity in the left lateral temporal cortex relative to unintelligible sentences. Moreover, responses to intelligibility in the sub-regions were differentially modulated by task demands. While the overall activation patterns of the anterior and posterior superior temporal sulcus and middle temporal gyrus (STS/MTG) were equivalent during both passive and active tasks, a middle portion of the STS/MTG was found to be selectively activated only during the active task under a refined analysis of sub-regional contributions. Our results not only confirm the critical role of the left lateral temporal cortex in auditory sentence comprehension but further demonstrate that task demands modulate functional specialization of the anterior-middle-posterior temporal sub-areas. PMID:25450147

  2. Plasticity in the neural coding of auditory space in the mammalian brain

    NASA Astrophysics Data System (ADS)

    King, Andrew J.; Parsons, Carl H.; Moore, David R.

    2000-10-01

    Sound localization relies on the neural processing of monaural and binaural spatial cues that arise from the way sounds interact with the head and external ears. Neurophysiological studies of animals raised with abnormal sensory inputs show that the map of auditory space in the superior colliculus is shaped during development by both auditory and visual experience. An example of this plasticity is provided by monaural occlusion during infancy, which leads to compensatory changes in auditory spatial tuning that tend to preserve the alignment between the neural representations of visual and auditory space. Adaptive changes also take place in sound localization behavior, as demonstrated by the fact that ferrets raised and tested with one ear plugged learn to localize as accurately as control animals. In both cases, these adjustments may involve greater use of monaural spectral cues provided by the other ear. Although plasticity in the auditory space map seems to be restricted to development, adult ferrets show some recovery of sound localization behavior after long-term monaural occlusion. The capacity for behavioral adaptation is, however, task dependent, because auditory spatial acuity and binaural unmasking (a measure of the spatial contribution to the "cocktail party effect") are permanently impaired by chronically plugging one ear, both in infancy but especially in adulthood. Experience-induced plasticity allows the neural circuitry underlying sound localization to be customized to individual characteristics, such as the size and shape of the head and ears, and to compensate for natural conductive hearing losses, including those associated with middle ear disease in infancy.

  3. Asymmetries of the human social brain in the visual, auditory and chemical modalities

    PubMed Central

    Brancucci, Alfredo; Lucci, Giuliana; Mazzatenta, Andrea; Tommasi, Luca

    2008-01-01

    Structural and functional asymmetries are present in many regions of the human brain responsible for motor control, sensory and cognitive functions and communication. Here, we focus on hemispheric asymmetries underlying the domain of social perception, broadly conceived as the analysis of information about other individuals based on acoustic, visual and chemical signals. By means of these cues the brain establishes the border between ‘self’ and ‘other’, and interprets the surrounding social world in terms of the physical and behavioural characteristics of conspecifics essential for impression formation and for creating bonds and relationships. We show that, considered from the standpoint of single- and multi-modal sensory analysis, the neural substrates of the perception of voices, faces, gestures, smells and pheromones, as evidenced by modern neuroimaging techniques, are characterized by a general pattern of right-hemispheric functional asymmetry that might benefit from other aspects of hemispheric lateralization rather than constituting a true specialization for social information. PMID:19064350

  4. Management of auditory hallucinations as a sequela of traumatic brain injury: a case report and a relevant literature review.

    PubMed

    Dobry, Yuriy; Novakovic, Vladan; Barkin, Robert L; Sundaram, Vikram K

    2014-01-01

    A patient with progressively worsening auditory hallucinations and 30-year history of traumatic brain injury (TBI) was reported. To formulate a comprehensive diagnostic and treatment approach to patients with auditory sensory disturbances and other neuropsychiatric sequela of a TBI, an electronic search of the major behavioral science databases (PubMed, PsycINFO, Medline) and a textbook review were conducted to retrieve studies detailing the clinical characteristics, biological mechanisms, and therapeutic approaches to post-TBI psychosis. Additional references were incorporated from the bibliographies of the retrieved articles. Although infrequent, auditory hallucinations is a debilitating complication of TBI that can manifest itself 4-5 years after the occurrence of TBI. Because the age range of TBI survivors is 15-24 years, and the chance of developing post-TBI psychosis is reported to be up to 20%, this chronic neuropsychiatric complication and the available treatment options warrant close scrutiny from the clinical and the biomedical research community. Our case report and literature review demonstrates a clear need for a large, well-designed randomized trials to compare properties and efficacies of different, available, and promising pharmacotherapy agents for the treatment of post-TBI psychosis. PMID:24263164

  5. Auditory brain-stem evoked potentials in cat after kainic acid induced neuronal loss. I. Superior olivary complex.

    PubMed

    Zaaroor, M; Starr, A

    1991-01-01

    Auditory brain-stem potentials (ABRs) were studied in cats for up to 45 days after kainic acid had been injected unilaterally or bilaterally into the superior olivary complex (SOC) to produce neuronal destruction while sparing fibers of passage and the terminals of axons of extrinsic origin connecting to SOC neurons. The components of the ABR in cat were labeled by their polarity at the vertex (P, for positive) and their order of appearance (the arabic numerals 1, 2, etc.). Component P1 can be further subdivided into 2 subcomponents labeled P1a and P1b. The correspondences we have assumed between the ABR components in cat and man are indicated by providing a Roman numeral designation for the human component in parentheses following the feline notation, e.g., P4 (V). With bilateral SOC destruction, there was a significant and marked attenuation of waves P2 (III), P3 (IV), P4 (V), P5 (VI), and the sustained potential shift (SPS) amounting to as much as 80% of preoperative values. Following unilateral SOC destruction the attenuation of many of these same ABR components, in response to stimulation of either ear, was up to 50%. No component of the ABR was totally abolished even when the SOC was lesioned 100% bilaterally. In unilaterally lesioned cats with extensive neuronal loss (greater than 75%) the latencies of the components beginning at P3 (IV) were delayed to stimulation of the ear ipsilateral to the injection site but not to stimulation of the ear contralateral to the injection. Binaural interaction components of the ABR were affected in proportion to the attenuation of the ABR. These results are compatible with multiple brain regions contributing to the generation of the components of the ABR beginning with P2 (III) and that components P3 (IV), P4 (V), and P5 (VI) and the sustained potential shift depend particularly on the integrity of the neurons of the SOC bilaterally. The neurons of the lateral subdivision (LSO) and the medial nucleus of the trapezoid body

  6. A unique cellular scaling rule in the avian auditory system.

    PubMed

    Corfield, Jeremy R; Long, Brendan; Krilow, Justin M; Wylie, Douglas R; Iwaniuk, Andrew N

    2016-06-01

    Although it is clear that neural structures scale with body size, the mechanisms of this relationship are not well understood. Several recent studies have shown that the relationship between neuron numbers and brain (or brain region) size are not only different across mammalian orders, but also across auditory and visual regions within the same brains. Among birds, similar cellular scaling rules have not been examined in any detail. Here, we examine the scaling of auditory structures in birds and show that the scaling rules that have been established in the mammalian auditory pathway do not necessarily apply to birds. In galliforms, neuronal densities decrease with increasing brain size, suggesting that auditory brainstem structures increase in size faster than neurons are added; smaller brains have relatively more neurons than larger brains. The cellular scaling rules that apply to auditory brainstem structures in galliforms are, therefore, different to that found in primate auditory pathway. It is likely that the factors driving this difference are associated with the anatomical specializations required for sound perception in birds, although there is a decoupling of neuron numbers in brain structures and hair cell numbers in the basilar papilla. This study provides significant insight into the allometric scaling of neural structures in birds and improves our understanding of the rules that govern neural scaling across vertebrates. PMID:26002617

  7. Delineation of a frequency-organized region isolated from the mouse primary auditory cortex

    PubMed Central

    Horie, Masao; Bo, Takeshi; Uchimura, Arikuni; Hishida, Ryuichi; Kudoh, Masaharu; Takahashi, Kuniyuki; Takebayashi, Hirohide; Shibuki, Katsuei

    2015-01-01

    The primary auditory cortex (AI) is the representative recipient of information from the ears in the mammalian cortex. However, the delineation of the AI is still controversial in a mouse. Recently, it was reported, using optical imaging, that two distinct areas of the AI, located ventrally and dorsally, are activated by high-frequency tones, whereas only one area is activated by low-frequency tones. Here, we show that the dorsal high-frequency area is an independent region that is separated from the rest of the AI. We could visualize the two distinct high-frequency areas using flavoprotein fluorescence imaging, as reported previously. SMI-32 immunolabeling revealed that the dorsal region had a different cytoarchitectural pattern from the rest of the AI. Specifically, the ratio of SMI-32-positive pyramidal neurons to nonpyramidal neurons was larger in the dorsal high-frequency area than the rest of the AI. We named this new region the dorsomedial field (DM). Retrograde tracing showed that neurons projecting to the DM were localized in the rostral part of the ventral division of the medial geniculate body with a distinct frequency organization, where few neurons projected to the AI. Furthermore, the responses of the DM to ultrasonic courtship songs presented by males were significantly greater in females than in males; in contrast, there was no sex difference in response to artificial pure tones. Our findings offer a basic outline on the processing of ultrasonic vocal information on the basis of the precisely subdivided, multiple frequency-organized auditory cortex map in mice. PMID:25695649

  8. The Application of the International Classification of Functioning, Disability and Health to Functional Auditory Consequences of Mild Traumatic Brain Injury.

    PubMed

    Werff, Kathy R Vander

    2016-08-01

    This article reviews the auditory consequences of mild traumatic brain injury (mTBI) within the context of the International Classification of Functioning, Disability and Health (ICF). Because of growing awareness of mTBI as a public health concern and the diverse and heterogeneous nature of the individual consequences, it is important to provide audiologists and other health care providers with a better understanding of potential implications in the assessment of levels of function and disability for individual interdisciplinary remediation planning. In consideration of body structures and function, the mechanisms of injury that may result in peripheral or central auditory dysfunction in mTBI are reviewed, along with a broader scope of effects of injury to the brain. The activity limitations and participation restrictions that may affect assessment and management in the context of an individual's personal factors and their environment are considered. Finally, a review of management strategies for mTBI from an audiological perspective as part of a multidisciplinary team is included. PMID:27489400

  9. Altered Small-World Brain Networks in Temporal Lobe in Patients with Schizophrenia Performing an Auditory Oddball Task

    PubMed Central

    Yu, Qingbao; Sui, Jing; Rachakonda, Srinivas; He, Hao; Pearlson, Godfrey; Calhoun, Vince D.

    2011-01-01

    The functional architecture of the human brain has been extensively described in terms of complex networks characterized by efficient small-world features. Recent functional magnetic resonance imaging (fMRI) studies have found altered small-world topological properties of brain functional networks in patients with schizophrenia (SZ) during the resting state. However, little is known about the small-world properties of brain networks in the context of a task. In this study, we investigated the topological properties of human brain functional networks derived from fMRI during an auditory oddball (AOD) task. Data were obtained from 20 healthy controls and 20 SZ; A left and a right task-related network which consisted of the top activated voxels in temporal lobe of each hemisphere were analyzed separately. All voxels were detected by group independent component analysis. Connectivity of the left and right task-related networks were estimated by partial correlation analysis and thresholded to construct a set of undirected graphs. The small-worldness values were decreased in both hemispheres in SZ. In addition, SZ showed longer shortest path length and lower global efficiency only in the left task-related networks. These results suggested small-world attributes are altered during the AOD task-related networks in SZ which provided further evidences for brain dysfunction of connectivity in SZ. PMID:21369355

  10. Regional brain atrophy development is related to specific aspects of clinical dysfunction in multiple sclerosis.

    PubMed

    Jasperse, Bas; Vrenken, Hugo; Sanz-Arigita, Ernesto; de Groot, Vincent; Smith, Stephen M; Polman, Chris H; Barkhof, Frederik

    2007-11-15

    Brain atrophy in multiple sclerosis (MS) is thought to reflect irreversible tissue damage leading to persistent clinical deficit. Little is known about the rate of atrophy in specific brain regions in relation to specific clinical deficits. We determined the displacement of the brain surface between two T1-weighted MRI images obtained at baseline and after a median follow-up time of 2.2 years for 79 recently diagnosed, mildly disabled MS patients. Voxel- and cluster-wise permutation-based statistics were used to identify brain regions in which atrophy development was significantly related to Expanded Disability Status Scale (EDSS), Timed Walk Test (TWT), Paced Auditory Serial Addition Test (PASAT) and 9-Hole Peg Test (HPT). Clusters were considered significant at a corrected cluster-wise p-value of 0.05. Worse EDSS change-score and worse follow-up EDSS were related to atrophy development of periventricular and brainstem regions and right-sided parietal, occipital and temporal regions. Worse PASAT at follow-up was significantly related to atrophy of the ventricles. A worse TWT change-score and worse follow-up TWT were exclusively related to atrophy around the ventricles and of the brainstem. Worse HPT change-score and worse follow-up HPT of either arm were significantly related to the atrophy of widely distributed peripheral regions, as well as atrophy of periventricular and brainstem regions. Our findings suggest that decline in ambulatory function is related to atrophy of central brain regions exclusively, whereas decline in neurologically more complex tasks for coordinated hand function is related to atrophy of both central and peripheral brain regions. PMID:17889567

  11. Specific Regional and Age-Related Small Noncoding RNA Expression Patterns Within Superior Temporal Gyrus of Typical Human Brains Are Less Distinct in Autism Brains

    PubMed Central

    Stamova, Boryana; Ander, Bradley P.; Barger, Nicole; Sharp, Frank R.

    2015-01-01

    Small noncoding RNAs play a critical role in regulating messenger RNA throughout brain development and when altered could have profound effects leading to disorders such as autism spectrum disorders (ASD). We assessed small noncoding RNAs, including microRNA and small nucleolar RNA, in superior temporal sulcus association cortex and primary auditory cortex in typical and ASD brains from early childhood to adulthood. Typical small noncoding RNA expression profiles were less distinct in ASD, both between regions and changes with age. Typical micro-RNA coexpression associations were absent in ASD brains. miR-132, miR-103, and miR-320 micro-RNAs were dysregulated in ASD and have previously been associated with autism spectrum disorders. These diminished region- and age-related micro-RNA expression profiles are in line with previously reported findings of attenuated messenger RNA and long noncoding RNA in ASD brain. This study demonstrates alterations in superior temporal sulcus in ASD, a region implicated in social impairment, and is the first to demonstrate molecular alterations in the primary auditory cortex. PMID:26350727

  12. Intracranial Recording and Source Localization of Auditory Brain Responses Elicited at the 50 ms Latency in Three Children Aged from 3 to 16 Years

    PubMed Central

    Asano, Eishi; Gumenyuk, Valentina; Juhász, Csaba; Wagner, Michael; Rothermel, Robert D.; Chugani, Harry T.

    2013-01-01

    Maturational studies of the auditory-evoked brain response at the 50 ms latency provide an insight into why this response is aberrant in a number of psychiatric disorders that have developmental origin. Here, using intracranial recordings we found that neuronal activity of the primary contributors to this response can be localised at the lateral part of Heschl’s gyrus already at the age of 3.5 years. This study provides results to support the notion that deviations in cognitive function(s) attributed to the auditory P50 in adults might involve abnormalities in neuronal activity of the frontal lobe or in the interaction between the frontal and temporal lobes. Validation and localisation of progenitors of the adults’ P50 in young children is a much-needed step in the understanding of the biological significance of different subcomponents that comprise the auditory P50 in the adult brain. In combination with other approaches investigating neuronal mechanisms of auditory P50, the present results contribute to the greater understanding of what and why neuronal activity underlying this response is aberrant in a number of brain dysfunctions. Moreover, the present source localisation results of auditory response at the 50 ms latency might be useful in paediatric neurosurgery practice. PMID:19701702

  13. Brain Correlates of Early Auditory Processing Are Attenuated by Expectations for Time and Pitch

    ERIC Educational Resources Information Center

    Lange, Kathrin

    2009-01-01

    The present study investigated how auditory processing is modulated by expectations for time and pitch by analyzing reaction times and event-related potentials (ERPs). In two experiments, tone sequences were presented to the participants, who had to discriminate whether the last tone of the sequence contained a short gap or was continuous…

  14. Characteristics of Auditory Agnosia in a Child with Severe Traumatic Brain Injury: A Case Report

    ERIC Educational Resources Information Center

    Hattiangadi, Nina; Pillion, Joseph P.; Slomine, Beth; Christensen, James; Trovato, Melissa K.; Speedie, Lynn J.

    2005-01-01

    We present a case that is unusual in many respects from other documented incidences of auditory agnosia, including the mechanism of injury, age of the individual, and location of neurological insult. The clinical presentation is one of disturbance in the perception of spoken language, music, pitch, emotional prosody, and temporal auditory…

  15. UNRECOGNIZED ERRORS DUE TO ANALOG FILTERING OF THE BRAIN-STEM AUDITORY EVOKED RESPONSE

    EPA Science Inventory

    The brainstem auditory evoked response (BAER) is used as a tool both in clinical evaluation and in toxicological research, where the subject is most often the laboratory rat. As in other species, interpretation of the rat BAER waveform is based on the latencies and amplitudes of ...

  16. Organization of projection neurons and local neurons of the primary auditory center in the fruit fly Drosophila melanogaster.

    PubMed

    Matsuo, Eriko; Seki, Haruyoshi; Asai, Tomonori; Morimoto, Takako; Miyakawa, Hiroyoshi; Ito, Kei; Kamikouchi, Azusa

    2016-04-15

    Acoustic communication between insects serves as an excellent model system for analyzing the neuronal mechanisms underlying auditory information processing. The detailed organization of auditory neural circuits in the brain has not yet been described. To understand the central auditory pathways, we used the brain of the fruit fly Drosophila melanogaster as a model and performed a large-scale analysis of the interneurons associated with the primary auditory center. By screening expression driver strains and performing single-cell labeling of these strains, we identified 44 types of interneurons innervating the primary auditory center. Five types were local interneurons whereas the other 39 types were projection interneurons connecting the primary auditory center with other brain regions. The projection neurons comprised three frequency-selective pathways and two frequency-embracive pathways. Mapping of their connection targets revealed that five neuropils in the brain-the wedge (WED), anterior ventrolateral protocerebrum, posterior ventrolateral protocerebrum (PVLP), saddle (SAD), and gnathal ganglia (GNG)-were intensively connected with the primary auditory center. In addition, several other neuropils, including visual and olfactory centers in the brain, were directly connected to the primary auditory center. The distribution patterns of the spines and boutons of the identified neurons suggest that auditory information is sent mainly from the primary auditory center to the PVLP, WED, SAD, GNG, and thoracico-abdominal ganglia. Based on these findings, we established the first comprehensive map of secondary auditory interneurons, which indicates the downstream information flow to parallel ascending pathways, multimodal pathways, and descending pathways. PMID:26762251

  17. Auditory spatial processing in Alzheimer’s disease

    PubMed Central

    Golden, Hannah L.; Nicholas, Jennifer M.; Yong, Keir X. X.; Downey, Laura E.; Schott, Jonathan M.; Mummery, Catherine J.; Crutch, Sebastian J.

    2015-01-01

    The location and motion of sounds in space are important cues for encoding the auditory world. Spatial processing is a core component of auditory scene analysis, a cognitively demanding function that is vulnerable in Alzheimer’s disease. Here we designed a novel neuropsychological battery based on a virtual space paradigm to assess auditory spatial processing in patient cohorts with clinically typical Alzheimer’s disease (n = 20) and its major variant syndrome, posterior cortical atrophy (n = 12) in relation to healthy older controls (n = 26). We assessed three dimensions of auditory spatial function: externalized versus non-externalized sound discrimination, moving versus stationary sound discrimination and stationary auditory spatial position discrimination, together with non-spatial auditory and visual spatial control tasks. Neuroanatomical correlates of auditory spatial processing were assessed using voxel-based morphometry. Relative to healthy older controls, both patient groups exhibited impairments in detection of auditory motion, and stationary sound position discrimination. The posterior cortical atrophy group showed greater impairment for auditory motion processing and the processing of a non-spatial control complex auditory property (timbre) than the typical Alzheimer’s disease group. Voxel-based morphometry in the patient cohort revealed grey matter correlates of auditory motion detection and spatial position discrimination in right inferior parietal cortex and precuneus, respectively. These findings delineate auditory spatial processing deficits in typical and posterior Alzheimer’s disease phenotypes that are related to posterior cortical regions involved in both syndromic variants and modulated by the syndromic profile of brain degeneration. Auditory spatial deficits contribute to impaired spatial awareness in Alzheimer’s disease and may constitute a novel perceptual model for probing brain network disintegration across the Alzheimer

  18. Anger Style, Psychopathology, and Regional Brain Activity

    PubMed Central

    Stewart, Jennifer L.; Levin, Rebecca L.; Sass, Sarah M.; Heller, Wendy; Miller, Gregory A.

    2010-01-01

    Depression and anxiety often involve high levels of trait anger and disturbances in anger expression. Reported anger experience and outward anger expression have recently been associated with left-biased asymmetry of frontal cortical activity, assumed to reflect approach motivation. However, different styles of anger expression could presumably involve different brain mechanisms and/or interact with psychopathology to produce various patterns of brain asymmetry. The present study explored these issues by comparing resting regional electroencephalographic activity in participants high in trait anger who differed in anger expression style (high anger-in, high anger-out, both) and participants low in trait anger, with depression and anxiety systematically assessed. Trait anger, not anger-in or anger-out, predicted left-biased asymmetry at medial frontal EEG sites. The anger-in group reported higher levels of anxious apprehension than did the anger-out group. Furthermore, anxious apprehension moderated the relationship between trait anger, anger-in, and asymmetry in favor of the left hemisphere. Results suggest that motivational direction is not always the driving force behind the relationship of anger and left frontal asymmetry. Findings also support a distinction between anxious apprehension and anxious arousal. PMID:18837620

  19. Far-field brainstem responses evoked by vestibular and auditory stimuli exhibit increases in interpeak latency as brain temperature is decreased

    NASA Technical Reports Server (NTRS)

    Hoffman, L. F.; Horowitz, J. M.

    1984-01-01

    The effect of decreasing of brain temperature on the brainstem auditory evoked response (BAER) in rats was investigated. Voltage pulses, applied to a piezoelectric crystal attached to the skull, were used to evoke stimuli in the auditory system by means of bone-conducted vibrations. The responses were recorded at 37 C and 34 C brain temperatures. The peaks of the BAER recorded at 34 C were delayed in comparison with the peaks from the 37 C wave, and the later peaks were more delayed than the earlier peaks. These results indicate that an increase in the interpeak latency occurs as the brain temperature is decreased. Preliminary experiments, in which responses to brief angular acceleration were used to measure the brainstem vestibular evoked response (BVER), have also indicated increases in the interpeak latency in response to the lowering of brain temperature.

  20. Maximum-likelihood estimation of channel-dependent trial-to-trial variability of auditory evoked brain responses in MEG

    PubMed Central

    2014-01-01

    Background We propose a mathematical model for multichannel assessment of the trial-to-trial variability of auditory evoked brain responses in magnetoencephalography (MEG). Methods Following the work of de Munck et al., our approach is based on the maximum likelihood estimation and involves an approximation of the spatio-temporal covariance of the contaminating background noise by means of the Kronecker product of its spatial and temporal covariance matrices. Extending the work of de Munck et al., where the trial-to-trial variability of the responses was considered identical to all channels, we evaluate it for each individual channel. Results Simulations with two equivalent current dipoles (ECDs) with different trial-to-trial variability, one seeded in each of the auditory cortices, were used to study the applicability of the proposed methodology on the sensor level and revealed spatial selectivity of the trial-to-trial estimates. In addition, we simulated a scenario with neighboring ECDs, to show limitations of the method. We also present an illustrative example of the application of this methodology to real MEG data taken from an auditory experimental paradigm, where we found hemispheric lateralization of the habituation effect to multiple stimulus presentation. Conclusions The proposed algorithm is capable of reconstructing lateralization effects of the trial-to-trial variability of evoked responses, i.e. when an ECD of only one hemisphere habituates, whereas the activity of the other hemisphere is not subject to habituation. Hence, it may be a useful tool in paradigms that assume lateralization effects, like, e.g., those involving language processing. PMID:24939398

  1. A case of ataxic diplegia, mental retardation, congenital nystagmus and abnormal auditory brain stem responses showing only waves I and II.

    PubMed

    Aiba, K; Yokochi, K; Ishikawa, T

    1986-01-01

    A three-year-old boy who had ataxic diplegia, mental retardation, horizontal pendular nystagmus with head nodding and abnormal auditory brain stem responses showing only waves I and II was presented. His clinical features coincided with recent reports in the Japanese literature of cases of a new syndrome that is congenital in origin and seen only in boys. PMID:3826555

  2. Suppression and facilitation of auditory neurons through coordinated acoustic and midbrain stimulation: investigating a deep brain stimulator for tinnitus

    NASA Astrophysics Data System (ADS)

    Offutt, Sarah J.; Ryan, Kellie J.; Konop, Alexander E.; Lim, Hubert H.

    2014-12-01

    Objective. The inferior colliculus (IC) is the primary processing center of auditory information in the midbrain and is one site of tinnitus-related activity. One potential option for suppressing the tinnitus percept is through deep brain stimulation via the auditory midbrain implant (AMI), which is designed for hearing restoration and is already being implanted in deaf patients who also have tinnitus. However, to assess the feasibility of AMI stimulation for tinnitus treatment we first need to characterize the functional connectivity within the IC. Previous studies have suggested modulatory projections from the dorsal cortex of the IC (ICD) to the central nucleus of the IC (ICC), though the functional properties of these projections need to be determined. Approach. In this study, we investigated the effects of electrical stimulation of the ICD on acoustic-driven activity within the ICC in ketamine-anesthetized guinea pigs. Main Results. We observed ICD stimulation induces both suppressive and facilitatory changes across ICC that can occur immediately during stimulation and remain after stimulation. Additionally, ICD stimulation paired with broadband noise stimulation at a specific delay can induce greater suppressive than facilitatory effects, especially when stimulating in more rostral and medial ICD locations. Significance. These findings demonstrate that ICD stimulation can induce specific types of plastic changes in ICC activity, which may be relevant for treating tinnitus. By using the AMI with electrode sites positioned with the ICD and the ICC, the modulatory effects of ICD stimulation can be tested directly in tinnitus patients.

  3. Brain activity underlying auditory perceptual learning during short period training: simultaneous fMRI and EEG recording

    PubMed Central

    2013-01-01

    Background There is an accumulating body of evidence indicating that neuronal functional specificity to basic sensory stimulation is mutable and subject to experience. Although fMRI experiments have investigated changes in brain activity after relative to before perceptual learning, brain activity during perceptual learning has not been explored. This work investigated brain activity related to auditory frequency discrimination learning using a variational Bayesian approach for source localization, during simultaneous EEG and fMRI recording. We investigated whether the practice effects are determined solely by activity in stimulus-driven mechanisms or whether high-level attentional mechanisms, which are linked to the perceptual task, control the learning process. Results The results of fMRI analyses revealed significant attention and learning related activity in left and right superior temporal gyrus STG as well as the left inferior frontal gyrus IFG. Current source localization of simultaneously recorded EEG data was estimated using a variational Bayesian method. Analysis of current localized to the left inferior frontal gyrus and the right superior temporal gyrus revealed gamma band activity correlated with behavioral performance. Conclusions Rapid improvement in task performance is accompanied by plastic changes in the sensory cortex as well as superior areas gated by selective attention. Together the fMRI and EEG results suggest that gamma band activity in the right STG and left IFG plays an important role during perceptual learning. PMID:23316957

  4. Potassium conductance dynamics confer robust spike-time precision in a neuromorphic model of the auditory brain stem

    PubMed Central

    Boahen, Kwabena

    2013-01-01

    A fundamental question in neuroscience is how neurons perform precise operations despite inherent variability. This question also applies to neuromorphic engineering, where low-power microchips emulate the brain using large populations of diverse silicon neurons. Biological neurons in the auditory pathway display precise spike timing, critical for sound localization and interpretation of complex waveforms such as speech, even though they are a heterogeneous population. Silicon neurons are also heterogeneous, due to a key design constraint in neuromorphic engineering: smaller transistors offer lower power consumption and more neurons per unit area of silicon, but also more variability between transistors and thus between silicon neurons. Utilizing this variability in a neuromorphic model of the auditory brain stem with 1,080 silicon neurons, we found that a low-voltage-activated potassium conductance (gKL) enables precise spike timing via two mechanisms: statically reducing the resting membrane time constant and dynamically suppressing late synaptic inputs. The relative contribution of these two mechanisms is unknown because blocking gKL in vitro eliminates dynamic adaptation but also lengthens the membrane time constant. We replaced gKL with a static leak in silico to recover the short membrane time constant and found that silicon neurons could mimic the spike-time precision of their biological counterparts, but only over a narrow range of stimulus intensities and biophysical parameters. The dynamics of gKL were required for precise spike timing robust to stimulus variation across a heterogeneous population of silicon neurons, thus explaining how neural and neuromorphic systems may perform precise operations despite inherent variability. PMID:23554436

  5. Long-range correlation properties in timing of skilled piano performance: the influence of auditory feedback and deep brain stimulation

    PubMed Central

    Herrojo Ruiz, María; Hong, Sang Bin; Hennig, Holger; Altenmüller, Eckart; Kühn, Andrea A.

    2014-01-01

    Unintentional timing deviations during musical performance can be conceived of as timing errors. However, recent research on humanizing computer-generated music has demonstrated that timing fluctuations that exhibit long-range temporal correlations (LRTC) are preferred by human listeners. This preference can be accounted for by the ubiquitous presence of LRTC in human tapping and rhythmic performances. Interestingly, the manifestation of LRTC in tapping behavior seems to be driven in a subject-specific manner by the LRTC properties of resting-state background cortical oscillatory activity. In this framework, the current study aimed to investigate whether propagation of timing deviations during the skilled, memorized piano performance (without metronome) of 17 professional pianists exhibits LRTC and whether the structure of the correlations is influenced by the presence or absence of auditory feedback. As an additional goal, we set out to investigate the influence of altering the dynamics along the cortico-basal-ganglia-thalamo-cortical network via deep brain stimulation (DBS) on the LRTC properties of musical performance. Specifically, we investigated temporal deviations during the skilled piano performance of a non-professional pianist who was treated with subthalamic-deep brain stimulation (STN-DBS) due to severe Parkinson's disease, with predominant tremor affecting his right upper extremity. In the tremor-affected right hand, the timing fluctuations of the performance exhibited random correlations with DBS OFF. By contrast, DBS restored long-range dependency in the temporal fluctuations, corresponding with the general motor improvement on DBS. Overall, the present investigations demonstrate the presence of LRTC in skilled piano performances, indicating that unintentional temporal deviations are correlated over a wide range of time scales. This phenomenon is stable after removal of the auditory feedback, but is altered by STN-DBS, which suggests that cortico

  6. Long-range correlation properties in timing of skilled piano performance: the influence of auditory feedback and deep brain stimulation.

    PubMed

    Herrojo Ruiz, María; Hong, Sang Bin; Hennig, Holger; Altenmüller, Eckart; Kühn, Andrea A

    2014-01-01

    Unintentional timing deviations during musical performance can be conceived of as timing errors. However, recent research on humanizing computer-generated music has demonstrated that timing fluctuations that exhibit long-range temporal correlations (LRTC) are preferred by human listeners. This preference can be accounted for by the ubiquitous presence of LRTC in human tapping and rhythmic performances. Interestingly, the manifestation of LRTC in tapping behavior seems to be driven in a subject-specific manner by the LRTC properties of resting-state background cortical oscillatory activity. In this framework, the current study aimed to investigate whether propagation of timing deviations during the skilled, memorized piano performance (without metronome) of 17 professional pianists exhibits LRTC and whether the structure of the correlations is influenced by the presence or absence of auditory feedback. As an additional goal, we set out to investigate the influence of altering the dynamics along the cortico-basal-ganglia-thalamo-cortical network via deep brain stimulation (DBS) on the LRTC properties of musical performance. Specifically, we investigated temporal deviations during the skilled piano performance of a non-professional pianist who was treated with subthalamic-deep brain stimulation (STN-DBS) due to severe Parkinson's disease, with predominant tremor affecting his right upper extremity. In the tremor-affected right hand, the timing fluctuations of the performance exhibited random correlations with DBS OFF. By contrast, DBS restored long-range dependency in the temporal fluctuations, corresponding with the general motor improvement on DBS. Overall, the present investigations demonstrate the presence of LRTC in skilled piano performances, indicating that unintentional temporal deviations are correlated over a wide range of time scales. This phenomenon is stable after removal of the auditory feedback, but is altered by STN-DBS, which suggests that cortico

  7. Prestimulus Network Integration of Auditory Cortex Predisposes Near-Threshold Perception Independently of Local Excitability

    PubMed Central

    Leske, Sabine; Ruhnau, Philipp; Frey, Julia; Lithari, Chrysa; Müller, Nadia; Hartmann, Thomas; Weisz, Nathan

    2015-01-01

    An ever-increasing number of studies are pointing to the importance of network properties of the brain for understanding behavior such as conscious perception. However, with regards to the influence of prestimulus brain states on perception, this network perspective has rarely been taken. Our recent framework predicts that brain regions crucial for a conscious percept are coupled prior to stimulus arrival, forming pre-established pathways of information flow and influencing perceptual awareness. Using magnetoencephalography (MEG) and graph theoretical measures, we investigated auditory conscious perception in a near-threshold (NT) task and found strong support for this framework. Relevant auditory regions showed an increased prestimulus interhemispheric connectivity. The left auditory cortex was characterized by a hub-like behavior and an enhanced integration into the brain functional network prior to perceptual awareness. Right auditory regions were decoupled from non-auditory regions, presumably forming an integrated information processing unit with the left auditory cortex. In addition, we show for the first time for the auditory modality that local excitability, measured by decreased alpha power in the auditory cortex, increases prior to conscious percepts. Importantly, we were able to show that connectivity states seem to be largely independent from local excitability states in the context of a NT paradigm. PMID:26408799

  8. Prestimulus Network Integration of Auditory Cortex Predisposes Near-Threshold Perception Independently of Local Excitability.

    PubMed

    Leske, Sabine; Ruhnau, Philipp; Frey, Julia; Lithari, Chrysa; Müller, Nadia; Hartmann, Thomas; Weisz, Nathan

    2015-12-01

    An ever-increasing number of studies are pointing to the importance of network properties of the brain for understanding behavior such as conscious perception. However, with regards to the influence of prestimulus brain states on perception, this network perspective has rarely been taken. Our recent framework predicts that brain regions crucial for a conscious percept are coupled prior to stimulus arrival, forming pre-established pathways of information flow and influencing perceptual awareness. Using magnetoencephalography (MEG) and graph theoretical measures, we investigated auditory conscious perception in a near-threshold (NT) task and found strong support for this framework. Relevant auditory regions showed an increased prestimulus interhemispheric connectivity. The left auditory cortex was characterized by a hub-like behavior and an enhanced integration into the brain functional network prior to perceptual awareness. Right auditory regions were decoupled from non-auditory regions, presumably forming an integrated information processing unit with the left auditory cortex. In addition, we show for the first time for the auditory modality that local excitability, measured by decreased alpha power in the auditory cortex, increases prior to conscious percepts. Importantly, we were able to show that connectivity states seem to be largely independent from local excitability states in the context of a NT paradigm. PMID:26408799

  9. Differences in brain circuitry for appetitive and reactive aggression as revealed by realistic auditory scripts

    PubMed Central

    Moran, James K.; Weierstall, Roland; Elbert, Thomas

    2014-01-01

    Aggressive behavior is thought to divide into two motivational elements: The first being a self-defensively motivated aggression against threat and a second, hedonically motivated “appetitive” aggression. Appetitive aggression is the less understood of the two, often only researched within abnormal psychology. Our approach is to understand it as a universal and adaptive response, and examine the functional neural activity of ordinary men (N = 50) presented with an imaginative listening task involving a murderer describing a kill. We manipulated motivational context in a between-subjects design to evoke appetitive or reactive aggression, against a neutral control, measuring activity with Magnetoencephalography (MEG). Results show differences in left frontal regions in delta (2–5 Hz) and alpha band (8–12 Hz) for aggressive conditions and right parietal delta activity differentiating appetitive and reactive aggression. These results validate the distinction of reward-driven appetitive aggression from reactive aggression in ordinary populations at the level of functional neural brain circuitry. PMID:25538590

  10. Hearing status in neonatal hyperbilirubinemia by auditory brain stem evoked response and transient evoked otoacoustic emission.

    PubMed

    Baradaranfar, Mohammad Hossein; Atighechi, Saeid; Dadgarnia, Mohammad Hossein; Jafari, Rozita; Karimi, Ghasem; Mollasadeghi, Abolfazl; Eslami, Zia; Baradarnfar, Amin

    2011-01-01

    Hyperbilirubinemia at neonatal period is one of the major deteriorating factors of the auditory system. If left untreated, it may cause certain cerebral damage. This study aims to evaluate the impact of hyperbilirubinemia on the hearing of neonate. This study was conducted on 35 newborn babies with jaundice (bilirubin more than 20 mg/dL). Auditory brainstem response (ABR) and transient evoked otoacoustic emission (TEOAE) tests were performed, after treatment and one year after. ABR test results indicated that 26 children (74.3%) had normal hearing but 9 (25.7%) suffered from an impairment. As for TEOAE test, 30 children (85.7%) passed whereas the remaining (14.3%) seemed to be failures. The comparative results of the two tests pointed to autonomic neuropathy /autonomic dysreflexia symptoms in 5 babies. Due to the high incidence of autonomic neuropathy/autonomic dysreflexia among hyperbilirubinemic babies, screening in this regard seems reasonable. Our result emphasizes the necessity of more experiments on the afflicted areas. PMID:21598220

  11. Alterations in brain-stem auditory evoked potentials among drug addicts

    PubMed Central

    Garg, Sonia; Sharma, Rajeev; Mittal, Shilekh; Thapar, Satish

    2015-01-01

    Objective: To compare the absolute latencies, the interpeak latencies, and amplitudes of different waveforms of brainstem auditory evoked potentials (BAEP) in different drug abusers and controls, and to identify early neurological damage in persons who abuse different drugs so that proper counseling and timely intervention can be undertaken. Methods: In this cross-sectional study, BAEP’s were assessed by a data acquisition and analysis system in 58 male drug abusers in the age group of 15-45 years as well as in 30 age matched healthy controls. The absolute peak latencies and the interpeak latencies of BAEP were analyzed by applying one way ANOVA and student t-test. The study was carried out at the GGS Medical College, Faridkot, Punjab, India between July 2012 and May 2013. Results: The difference in the absolute peak latencies and interpeak latencies of BAEP in the 2 groups was found to be statistically significant in both the ears (p<0.05). However, the difference in the amplitude ratio in both the ears was found to be statistically insignificant. Conclusion: Chronic intoxication by different drugs has been extensively associated with prolonged absolute peak latencies and interpeak latencies of BAEP in drug abusers reflecting an adverse effect of drug dependence on neural transmission in central auditory nerve pathways. PMID:26166594

  12. Instrument specific brain activation in sensorimotor and auditory representation in musicians.

    PubMed

    Gebel, B; Braun, Ch; Kaza, E; Altenmüller, E; Lotze, M

    2013-07-01

    Musicians show a remarkable ability to interconnect motor patterns and sensory processing in the somatosensory and auditory domains. Many of these processes are specific for the instrument used. We were interested in the cerebral and cerebellar representations of these instrument-specific changes and therefore applied functional magnetic resonance imaging (fMRI) in two groups of instrumentalists with different instrumental training for comparable periods (approximately 15 years). The first group (trumpet players) uses tight finger and lip interaction; the second (pianists as control group) uses only the extremities for performance. fMRI tasks were balanced for instructions (piano and trumpet notes), sensory feedback (keypad and trumpet), and hand-lip interaction on the trumpet. During fMRI, both groups switched between different devices (trumpet or keypad) and performance was combined with or without auditory feedback. Playing the trumpet without any tone emission or using the mouthpiece showed an instrument training-specific activation increase in trumpet players. This was evident for the posterior-superior cerebellar hemisphere, the dominant primary sensorimotor cortex, and the left Heschl's gyrus. Additionally, trumpet players showed increased activity in the bilateral Heschl's gyrus during actual trumpet playing, although they showed significantly decreased loudness while playing with the mouthpiece in the scanner compared to pianists. PMID:23454048

  13. Auditory-limbic interactions in chronic tinnitus: Challenges for neuroimaging research.

    PubMed

    Leaver, Amber M; Seydell-Greenwald, Anna; Rauschecker, Josef P

    2016-04-01

    Tinnitus is a widespread auditory disorder affecting approximately 10-15% of the population, often with debilitating consequences. Although tinnitus commonly begins with damage to the auditory system due to loud-noise exposure, aging, or other etiologies, the exact neurophysiological basis of chronic tinnitus remains unknown. Many researchers point to a central auditory origin of tinnitus; however, a growing body of evidence also implicates other brain regions, including the limbic system. Correspondingly, we and others have proposed models of tinnitus in which the limbic and auditory systems both play critical roles and interact with one another. Specifically, we argue that damage to the auditory system generates an initial tinnitus signal, consistent with previous research. In our model, this "transient" tinnitus is suppressed when a limbic frontostriatal network, comprised of ventromedial prefrontal cortex and ventral striatum, successfully modulates thalamocortical transmission in the auditory system. Thus, in chronic tinnitus, limbic-system damage and resulting inefficiency of auditory-limbic interactions prevents proper compensation of the tinnitus signal. Neuroimaging studies utilizing connectivity methods like resting-state fMRI and diffusion MRI continue to uncover tinnitus-related anomalies throughout auditory, limbic, and other brain systems. However, directly assessing interactions between these brain regions and networks has proved to be more challenging. Here, we review existing empirical support for models of tinnitus stressing a critical role for involvement of "non-auditory" structures in tinnitus pathophysiology, and discuss the possible impact of newly refined connectivity techniques from neuroimaging on tinnitus research. PMID:26299843

  14. Auditory imagery: empirical findings.

    PubMed

    Hubbard, Timothy L

    2010-03-01

    The empirical literature on auditory imagery is reviewed. Data on (a) imagery for auditory features (pitch, timbre, loudness), (b) imagery for complex nonverbal auditory stimuli (musical contour, melody, harmony, tempo, notational audiation, environmental sounds), (c) imagery for verbal stimuli (speech, text, in dreams, interior monologue), (d) auditory imagery's relationship to perception and memory (detection, encoding, recall, mnemonic properties, phonological loop), and (e) individual differences in auditory imagery (in vividness, musical ability and experience, synesthesia, musical hallucinosis, schizophrenia, amusia) are considered. It is concluded that auditory imagery (a) preserves many structural and temporal properties of auditory stimuli, (b) can facilitate auditory discrimination but interfere with auditory detection, (c) involves many of the same brain areas as auditory perception, (d) is often but not necessarily influenced by subvocalization, (e) involves semantically interpreted information and expectancies, (f) involves depictive components and descriptive components, (g) can function as a mnemonic but is distinct from rehearsal, and (h) is related to musical ability and experience (although the mechanisms of that relationship are not clear). PMID:20192565

  15. The influence of cochlear spectral processing on the timing and amplitude of the speech-evoked auditory brain stem response

    PubMed Central

    Nuttall, Helen E.; Moore, David R.; Barry, Johanna G.; Krumbholz, Katrin

    2015-01-01

    The speech-evoked auditory brain stem response (speech ABR) is widely considered to provide an index of the quality of neural temporal encoding in the central auditory pathway. The aim of the present study was to evaluate the extent to which the speech ABR is shaped by spectral processing in the cochlea. High-pass noise masking was used to record speech ABRs from delimited octave-wide frequency bands between 0.5 and 8 kHz in normal-hearing young adults. The latency of the frequency-delimited responses decreased from the lowest to the highest frequency band by up to 3.6 ms. The observed frequency-latency function was compatible with model predictions based on wave V of the click ABR. The frequency-delimited speech ABR amplitude was largest in the 2- to 4-kHz frequency band and decreased toward both higher and lower frequency bands despite the predominance of low-frequency energy in the speech stimulus. We argue that the frequency dependence of speech ABR latency and amplitude results from the decrease in cochlear filter width with decreasing frequency. The results suggest that the amplitude and latency of the speech ABR may reflect interindividual differences in cochlear, as well as central, processing. The high-pass noise-masking technique provides a useful tool for differentiating between peripheral and central effects on the speech ABR. It can be used for further elucidating the neural basis of the perceptual speech deficits that have been associated with individual differences in speech ABR characteristics. PMID:25787954

  16. Brain dynamics that correlate with effects of learning on auditory distance perception

    PubMed Central

    Wisniewski, Matthew G.; Mercado, Eduardo; Church, Barbara A.; Gramann, Klaus; Makeig, Scott

    2014-01-01

    Accuracy in auditory distance perception can improve with practice and varies for sounds differing in familiarity. Here, listeners were trained to judge the distances of English, Bengali, and backwards speech sources pre-recorded at near (2-m) and far (30-m) distances. Listeners' accuracy was tested before and after training. Improvements from pre-test to post-test were greater for forward speech, demonstrating a learning advantage for forward speech sounds. Independent component (IC) processes identified in electroencephalographic (EEG) data collected during pre- and post-testing revealed three clusters of ICs across subjects with stimulus-locked spectral perturbations related to learning and accuracy. One cluster exhibited a transient stimulus-locked increase in 4–8 Hz power (theta event-related synchronization; ERS) that was smaller after training and largest for backwards speech. For a left temporal cluster, 8–12 Hz decreases in power (alpha event-related desynchronization; ERD) were greatest for English speech and less prominent after training. In contrast, a cluster of IC processes centered at or near anterior portions of the medial frontal cortex showed learning-related enhancement of sustained increases in 10–16 Hz power (upper-alpha/low-beta ERS). The degree of this enhancement was positively correlated with the degree of behavioral improvements. Results suggest that neural dynamics in non-auditory cortical areas support distance judgments. Further, frontal cortical networks associated with attentional and/or working memory processes appear to play a role in perceptual learning for source distance. PMID:25538550

  17. Reality of auditory verbal hallucinations

    PubMed Central

    Valkonen-Korhonen, Minna; Holi, Matti; Therman, Sebastian; Lehtonen, Johannes; Hari, Riitta

    2009-01-01

    Distortion of the sense of reality, actualized in delusions and hallucinations, is the key feature of psychosis but the underlying neuronal correlates remain largely unknown. We studied 11 highly functioning subjects with schizophrenia or schizoaffective disorder while they rated the reality of auditory verbal hallucinations (AVH) during functional magnetic resonance imaging (fMRI). The subjective reality of AVH correlated strongly and specifically with the hallucination-related activation strength of the inferior frontal gyri (IFG), including the Broca's language region. Furthermore, how real the hallucination that subjects experienced was depended on the hallucination-related coupling between the IFG, the ventral striatum, the auditory cortex, the right posterior temporal lobe, and the cingulate cortex. Our findings suggest that the subjective reality of AVH is related to motor mechanisms of speech comprehension, with contributions from sensory and salience-detection-related brain regions as well as circuitries related to self-monitoring and the experience of agency. PMID:19620178

  18. Regional brain monitoring in the neurocritical care unit.

    PubMed

    Frontera, Jennifer; Ziai, Wendy; O'Phelan, Kristine; Leroux, Peter D; Kirkpatrick, Peter J; Diringer, Michael N; Suarez, Jose I

    2015-06-01

    Regional multimodality monitoring has evolved over the last several years as a tool to understand the mechanisms of brain injury and brain function at the cellular level. Multimodality monitoring offers an important augmentation to the clinical exam and is especially useful in comatose neurocritical care patients. Cerebral microdialysis, brain tissue oxygen monitoring, and cerebral blood flow monitoring all offer insight into permutations in brain chemistry and function that occur in the context of brain injury. These tools may allow for development of individual therapeutic strategies that are mechanistically driven and goal-directed. We present a summary of the discussions that took place during the Second Neurocritical Care Research Conference regarding regional brain monitoring. PMID:25832349

  19. Regional deconvolution method for partial volume correction in brain PET

    NASA Astrophysics Data System (ADS)

    Rusinek, Henry; Tsui, Wai-Hon; de Leon, Mony J.

    2001-05-01

    Correction of PET images for partial volume effects (PVE) is of particular utility in studies of metabolism in brain aging and brain disorders. PVE is commonly corrected using voxel-by- voxel factors obtained from a high resolution brain mask (obtained from the coregistered MR scan), after convolution with the point spread function (PSF) of the imaging system. In a recently proposed regional deconvolution (RD) method, the observed regional activity is expressed as linear combinations of the true metabolic activity. The weights are obtained by integrating the PSF over the geometric extent of the brain regions. We have analyzed the accuracy of RD and two other PVE correction algorithms under a variety of conditions using simulated PET scans. Each of the brain regions was assigned a distribution of metabolic activity, with gray matter/white matter contrast representative of subjects in several age categories. Simulations were performed over a wide range of PET resolutions. The influence of PET/MR misregistration and heterogeneity of brain metabolism were also evaluated. Our results demonstrate the importance of correcting PET metabolic images for PVE. Without such correction, the regional brain activity values are contaminated with 30 - 40% errors. Under most conditions studied, the accuracy of RD and of the three- compartmental method were superior to the accuracy of the two- compartmental method. Our study provides the first demonstration of the feasibility of RD algorithm to provide accurate correction for a large number (n equals 109) of brain compartments. PVE correction methods appear to be promising tools in studies of metabolism in normal brain, brain aging, and brain disorders.

  20. Naming the same entities from visual or from auditory stimulation engages similar regions of left inferotemporal cortices.

    PubMed

    Tranel, Daniel; Grabowski, Thomas J; Lyon, Jill; Damasio, Hanna

    2005-08-01

    We have proposed that the left inferotemporal (IT) region contains structures that mediate between conceptual knowledge retrieval and word-form retrieval, and we have hypothesized that these structures are utilized for word retrieval irrespective of the sensory modality through which an entity is apprehended, thus being "modality neutral." We tested this idea in two sensory modalities, visual and auditory, and for two categories of concrete entities, tools and animals. In a PET experiment, 10 normal participants named tools and animals either from pictures or from characteristic sounds (e.g., "scissors" from a picture of a scissors or from the sound of a scissors cutting; "rooster" from a picture of a rooster or from the sound of a rooster crowing). Visual and auditory naming of tools activated the left posterior/lateral IT; visual and auditory naming of animals activated the left anterior/ventral IT. For both tools and animals, the left IT activations were similar in location and magnitude regardless of whether participants were naming entities from pictures or from sounds. The results provide novel evidence to support the notion that left IT structures contain "modality-neutral" systems for mediating between conceptual knowledge and word retrieval. PMID:16197684

  1. 40 Hz auditory steady state response to linguistic features of stimuli during auditory hallucinations.

    PubMed

    Ying, Jun; Yan, Zheng; Gao, Xiao-rong

    2013-10-01

    The auditory steady state response (ASSR) may reflect activity from different regions of the brain, depending on the modulation frequency used. In general, responses induced by low rates (≤40 Hz) emanate mostly from central structures of the brain, and responses from high rates (≥80 Hz) emanate mostly from the peripheral auditory nerve or brainstem structures. Besides, it was reported that the gamma band ASSR (30-90 Hz) played an important role in working memory, speech understanding and recognition. This paper investigated the 40 Hz ASSR evoked by modulated speech and reversed speech. The speech was Chinese phrase voice, and the noise-like reversed speech was obtained by temporally reversing the speech. Both auditory stimuli were modulated with a frequency of 40 Hz. Ten healthy subjects and 5 patients with hallucination symptom participated in the experiment. Results showed reduction in left auditory cortex response when healthy subjects listened to the reversed speech compared with the speech. In contrast, when the patients who experienced auditory hallucinations listened to the reversed speech, the auditory cortex of left hemispheric responded more actively. The ASSR results were consistent with the behavior results of patients. Therefore, the gamma band ASSR is expected to be helpful for rapid and objective diagnosis of hallucination in clinic. PMID:24142731

  2. Auditory Neuroimaging with fMRI and PET

    PubMed Central

    Talavage, Thomas M.; Gonzalez-Castillo, Javier; Scott, Sophie K.

    2013-01-01

    For much of the past 30 years, investigations of auditory perception and language have been enhanced or even driven by the use of functional neuroimaging techniques that specialize in localization of central responses. Beginning with investigations using positron emission tomography (PET) and gradually shifting primarily to usage of functional magnetic resonance imaging (fMRI), auditory neuroimaging has greatly advanced our understanding of the organization and response properties of brain regions critical to the perception of and communication with the acoustic world in which we live. As the complexity of the questions being addressed has increased, the techniques, experiments and analyses applied have also become more nuanced and specialized. A brief review of the history of these investigations sets the stage for an overview and analysis of how these neuroimaging modalities are becoming ever more effective tools for understanding the auditory brain. We conclude with a brief discussion of open methodological issues as well as potential clinical applications for auditory neuroimaging. PMID:24076424

  3. Electrophysiological correlates of auditory change detection and change deafness in complex auditory scenes.

    PubMed

    Puschmann, Sebastian; Sandmann, Pascale; Ahrens, Janina; Thorne, Jeremy; Weerda, Riklef; Klump, Georg; Debener, Stefan; Thiel, Christiane M

    2013-07-15

    Change deafness describes the failure to perceive even intense changes within complex auditory input, if the listener does not attend to the changing sound. Remarkably, previous psychophysical data provide evidence that this effect occurs independently of successful stimulus encoding, indicating that undetected changes are processed to some extent in auditory cortex. Here we investigated cortical representations of detected and undetected auditory changes using electroencephalographic (EEG) recordings and a change deafness paradigm. We applied a one-shot change detection task, in which participants listened successively to three complex auditory scenes, each of them consisting of six simultaneously presented auditory streams. Listeners had to decide whether all scenes were identical or whether the pitch of one stream was changed between the last two presentations. Our data show significantly increased middle-latency Nb responses for both detected and undetected changes as compared to no-change trials. In contrast, only successfully detected changes were associated with a later mismatch response in auditory cortex, followed by increased N2, P3a and P3b responses, originating from hierarchically higher non-sensory brain regions. These results strengthen the view that undetected changes are successfully encoded at sensory level in auditory cortex, but fail to trigger later change-related cortical responses that lead to conscious perception of change. PMID:23466938

  4. Comparisons of MRI images, and auditory-related and vocal-related protein expressions in the brain of echolocation bats and rodents.

    PubMed

    Hsiao, Chun-Jen; Hsu, Chih-Hsiang; Lin, Ching-Lung; Wu, Chung-Hsin; Jen, Philip Hung-Sun

    2016-08-17

    Although echolocating bats and other mammals share the basic design of laryngeal apparatus for sound production and auditory system for sound reception, they have a specialized laryngeal mechanism for ultrasonic sound emissions as well as a highly developed auditory system for processing species-specific sounds. Because the sounds used by bats for echolocation and rodents for communication are quite different, there must be differences in the central nervous system devoted to producing and processing species-specific sounds between them. The present study examines the difference in the relative size of several brain structures and expression of auditory-related and vocal-related proteins in the central nervous system of echolocation bats and rodents. Here, we report that bats using constant frequency-frequency-modulated sounds (CF-FM bats) and FM bats for echolocation have a larger volume of midbrain nuclei (inferior and superior colliculi) and cerebellum relative to the size of the brain than rodents (mice and rats). However, the former have a smaller volume of the cerebrum and olfactory bulb, but greater expression of otoferlin and forkhead box protein P2 than the latter. Although the size of both midbrain colliculi is comparable in both CF-FM and FM bats, CF-FM bats have a larger cerebrum and greater expression of otoferlin and forkhead box protein P2 than FM bats. These differences in brain structure and protein expression are discussed in relation to their biologically relevant sounds and foraging behavior. PMID:27337384

  5. Brain activity is related to individual differences in the number of items stored in auditory short-term memory for pitch: evidence from magnetoencephalography.

    PubMed

    Grimault, Stephan; Nolden, Sophie; Lefebvre, Christine; Vachon, François; Hyde, Krista; Peretz, Isabelle; Zatorre, Robert; Robitaille, Nicolas; Jolicoeur, Pierre

    2014-07-01

    We used magnetoencephalography (MEG) to examine brain activity related to the maintenance of non-verbal pitch information in auditory short-term memory (ASTM). We focused on brain activity that increased with the number of items effectively held in memory by the participants during the retention interval of an auditory memory task. We used very simple acoustic materials (i.e., pure tones that varied in pitch) that minimized activation from non-ASTM related systems. MEG revealed neural activity in frontal, temporal, and parietal cortices that increased with a greater number of items effectively held in memory by the participants during the maintenance of pitch representations in ASTM. The present results reinforce the functional role of frontal and temporal cortices in the retention of pitch information in ASTM. This is the first MEG study to provide both fine spatial localization and temporal resolution on the neural mechanisms of non-verbal ASTM for pitch in relation to individual differences in the capacity of ASTM. This research contributes to a comprehensive understanding of the mechanisms mediating the representation and maintenance of basic non-verbal auditory features in the human brain. PMID:24642285

  6. Age-Related Changes in Transient and Oscillatory Brain Responses to Auditory Stimulation during Early Adolescence

    ERIC Educational Resources Information Center

    Poulsen, Catherine; Picton, Terence W.; Paus, Tomas

    2009-01-01

    Maturational changes in the capacity to process quickly the temporal envelope of sound have been linked to language abilities in typically developing individuals. As part of a longitudinal study of brain maturation and cognitive development during adolescence, we employed dense-array EEG and spatiotemporal source analysis to characterize…

  7. On Expression Patterns and Developmental Origin of Human Brain Regions

    PubMed Central

    Kirsch, Lior; Chechik, Gal

    2016-01-01

    Anatomical substructures of the human brain have characteristic cell-types, connectivity and local circuitry, which are reflected in area-specific transcriptome signatures, but the principles governing area-specific transcription and their relation to brain development are still being studied. In adult rodents, areal transcriptome patterns agree with the embryonic origin of brain regions, but the processes and genes that preserve an embryonic signature in regional expression profiles were not quantified. Furthermore, it is not clear how embryonic-origin signatures of adult-brain expression interplay with changes in expression patterns during development. Here we first quantify which genes have regional expression-patterns related to the developmental origin of brain regions, using genome-wide mRNA expression from post-mortem adult human brains. We find that almost all human genes (92%) exhibit an expression pattern that agrees with developmental brain-region ontology, but that this agreement changes at multiple phases during development. Agreement is particularly strong in neuron-specific genes, but also in genes that are not spatially correlated with neuron-specific or glia-specific markers. Surprisingly, agreement is also stronger in early-evolved genes. We further find that pairs of similar genes having high agreement to developmental region ontology tend to be more strongly correlated or anti-correlated, and that the strength of spatial correlation changes more strongly in gene pairs with stronger embryonic signatures. These results suggest that transcription regulation of most genes in the adult human brain is spatially tuned in a way that changes through life, but in agreement with development-determined brain regions. PMID:27564987

  8. Scans Spot Brain Region That Misfires in Depressed People

    MedlinePlus

    ... Scans Spot Brain Region That Misfires in Depressed People Contrary to previous thinking, the habenula is less ... bad experiences acts in an unexpected way in people with depression, a small study finds. One theory ...

  9. Indices of Regional Brain Atrophy: Formulae and Nomenclature

    PubMed Central

    Arias-Carrión, Oscar

    2015-01-01

    The pattern of brain atrophy helps to discriminate normal age-related changes from neurodegenerative diseases. Albeit indices of regional brain atrophy have proven to be a parameter useful in the early diagnosis and differential diagnosis of some neurodegenerative diseases, indices of absolute regional atrophy still have some important limitations. We propose using indices of relative atrophy for representing how the volume of a given region of interest (ROI) changes over time in comparison to changes in global brain measures over the same time. A second problem in morphometric studies is terminology. There is a lack of systematization naming indices and the same measure can be named with different terms by different research groups or imaging softwares. This limits the understanding and discussion of studies. In this technological report, we provide a general description on how to compute indices of absolute and relative regional brain atrophy and propose a standardized nomenclature. PMID:26261753

  10. The combined monitoring of brain stem auditory evoked potentials and intracranial pressure in coma. A study of 57 patients.

    PubMed Central

    García-Larrea, L; Artru, F; Bertrand, O; Pernier, J; Mauguière, F

    1992-01-01

    Continuous monitoring of brainstem auditory evoked potentials (BAEPs) was carried out in 57 comatose patients for periods ranging from 5 hours to 13 days. In 53 cases intracranial pressure (ICP) was also simultaneously monitored. The study of relative changes of evoked potentials over time proved more relevant to prognosis than the mere consideration of "statistical normality" of waveforms; thus progressive degradation of the BAEPs was associated with a bad outcome even if the responses remained within normal limits. Contrary to previous reports, a normal BAEP obtained during the second week of coma did not necessarily indicate a good vital outcome; it could, however, do so in cases with a low probability of secondary insults. The simultaneous study of BAEPs and ICP showed that apparently significant (greater than 40 mm Hg) acute rises in ICP were not always followed by BAEP changes. The stability of BAEP's despite "significant" ICP rises was associated in our patients with a high probability of survival, while prolongation of central latency of BAEPs in response to ICP modifications was almost invariably followed by brain death. Continuous monitoring of brainstem responses provided a useful physiological counterpart to physical parameters such as ICP. Serial recording of cortical EPs should be added to BAEP monitoring to permit the early detection of rostrocaudal deterioration. Images PMID:1402970

  11. Neuronal coupling by endogenous electric fields: cable theory and applications to coincidence detector neurons in the auditory brain stem.

    PubMed

    Goldwyn, Joshua H; Rinzel, John

    2016-04-01

    The ongoing activity of neurons generates a spatially and time-varying field of extracellular voltage (Ve). ThisVefield reflects population-level neural activity, but does it modulate neural dynamics and the function of neural circuits? We provide a cable theory framework to study how a bundle of model neurons generatesVeand how thisVefeeds back and influences membrane potential (Vm). We find that these "ephaptic interactions" are small but not negligible. The model neural population can generateVewith millivolt-scale amplitude, and thisVeperturbs theVmof "nearby" cables and effectively increases their electrotonic length. After using passive cable theory to systematically study ephaptic coupling, we explore a test case: the medial superior olive (MSO) in the auditory brain stem. The MSO is a possible locus of ephaptic interactions: sounds evoke large (millivolt scale)Vein vivo in this nucleus. TheVeresponse is thought to be generated by MSO neurons that perform a known neuronal computation with submillisecond temporal precision (coincidence detection to encode sound source location). Using a biophysically based model of MSO neurons, we find millivolt-scale ephaptic interactions consistent with the passive cable theory results. These subtle membrane potential perturbations induce changes in spike initiation threshold, spike time synchrony, and time difference sensitivity. These results suggest that ephaptic coupling may influence MSO function. PMID:26823512

  12. Mammalian CNS barosensitivity: studied by brain-stem auditory-evoked potential in mice.

    PubMed

    Chen, Ruiyong; Xiao, Weibing; Li, Jun; He, Jia; Chen, Haiting

    2012-01-01

    High pressure nervous syndrome (HPNS) is an instinctive response of mammalian high-class nervous functions to increased hydrostatic pressure. Electrophysiological activity of mammalian central nervous system (CNS), including brainstem auditory-evoked potential (BAEP), has characteristic changes under pressure. Here we recorded BAEP of 63 mice exposed to 0-4.0 MPa. The results showed that interpeak latencies between wave I and wave IV (IPL1-4) and their changes under pressures (deltaIPL1-4) responded to increasing pressure in a biphase pattern, shortened under pressure from 0 to 0.7MPa, then prolonged later. There were significantly negative correlations between base IPL1-4s and deltaIPL1-4s (p < 0.01). Individual IPL1-4s were supposed to respond to increasing pressure in a relative steady pattern in accordance with its base IPL1-4s. Those with shorter-base IPL1-4 presented direct increases in IPL1-4. However, those with longer-base IPL1-4 had a decreased IPL1-4 under small to moderate pressure then rebounded later. Our results suggested that mammalian CNS functions were susceptible to small to moderate pressure, as well as a higher pressure than 1.0MPa. Mice, as a statistical mass, had an "optimum" pressure about 0.7MPa, rather than atmospheric pressure, referred as shortest IPL1-4s. An individual's response to high pressure might be relied on his base biological condition. Our results highlighted a new approach to investigate a practical strategy to medical selecting barotolerant candidates for deep divers. Diversity of individual susceptibility to hydrostatic pressure was under discussed. Underlying mechanisms of the "optimum" pressure for CNS function and its significance to neurophysiology remain open to further exploration. PMID:22400446

  13. Auditory Verbal Hallucinations and Brain Dysconnectivity in the Perisylvian Language Network: A Multimodal Investigation

    PubMed Central

    Pettersson-Yeo, William; Allen, Paul; Catani, Marco; Williams, Steven; Barsaglini, Alessio; Kambeitz-Ilankovic, Lana M.; McGuire, Philip; Mechelli, Andrea

    2015-01-01

    Neuroimaging studies of schizophrenia have indicated that the development of auditory verbal hallucinations (AVHs) is associated with altered structural and functional connectivity within the perisylvian language network. However, these studies focussed mainly on either structural or functional alterations in patients with chronic schizophrenia. Therefore, they were unable to examine the relationship between the 2 types of measures and could not establish whether the observed alterations would be expressed in the early stage of the illness. We used diffusion tensor imaging and functional magnetic resonance imaging to examine white matter integrity and functional connectivity within the left perisylvian language network of 46 individuals with an at risk mental state for psychosis or a first episode of the illness, including 28 who had developed AVH group and 18 who had not (nonauditory verbal hallucination [nAVH] group), and 22 healthy controls. Inferences were made at P < .05 (corrected). The nAVH group relative to healthy controls showed a reduction of both white matter integrity and functional connectivity as well as a disruption of the normal structure−function relationship along the fronto-temporal pathway. For all measures, the AVH group showed intermediate values between healthy controls and the nAVH group. These findings seem to suggest that, in the early stage of the disorder, a significant impairment of fronto-temporal connectivity is evident in patients who do not experience AVHs. This is consistent with the hypothesis that, whilst mild disruption of connectivity might still enable the emergence of AVHs, more severe alterations may prevent the occurrence of the hallucinatory experience. PMID:24361862

  14. Decreases in energy and increases in phase locking of event-related oscillations to auditory stimuli occur during adolescence in human and rodent brain.

    PubMed

    Ehlers, Cindy L; Wills, Derek N; Desikan, Anita; Phillips, Evelyn; Havstad, James

    2014-01-01

    Synchrony of phase (phase locking) of event-related oscillations (EROs) within and between different brain areas has been suggested to reflect communication exchange between neural networks and as such may be a sensitive and translational measure of changes in brain remodeling that occur during adolescence. This study sought to investigate developmental changes in EROs using a similar auditory event-related potential (ERP) paradigm in both rats and humans. Energy and phase variability of EROs collected from 38 young adult men (aged 18-25 years), 33 periadolescent boys (aged 10-14 years), 15 male periadolescent rats [at postnatal day (PD) 36] and 19 male adult rats (at PD103) were investigated. Three channels of ERP data (frontal cortex, central cortex and parietal cortex) were collected from the humans using an 'oddball plus noise' paradigm that was presented under passive (no behavioral response required) conditions in the periadolescents and under active conditions (where each subject was instructed to depress a counter each time he detected an infrequent target tone) in adults and adolescents. ERPs were recorded in rats using only the passive paradigm. In order to compare the tasks used in rats to those used in humans, we first studied whether three ERO measures [energy, phase locking index (PLI) within an electrode site and phase difference locking index (PDLI) between different electrode sites] differentiated the 'active' from 'passive' ERP tasks. Secondly, we explored our main question of whether the three ERO measures differentiated adults from periadolescents in a similar manner in both humans and rats. No significant changes were found in measures of ERO energy between the active and passive tasks in the periadolescent human participants. There was a smaller but significant increase in PLI but not PDLI as a function of active task requirements. Developmental differences were found in energy, PLI and PDLI values between the periadolescents and adults in

  15. Regional growth and atlasing of the developing human brain

    PubMed Central

    Makropoulos, Antonios; Aljabar, Paul; Wright, Robert; Hüning, Britta; Merchant, Nazakat; Arichi, Tomoki; Tusor, Nora; Hajnal, Joseph V.; Edwards, A. David; Counsell, Serena J.; Rueckert, Daniel

    2016-01-01

    Detailed morphometric analysis of the neonatal brain is required to characterise brain development and define neuroimaging biomarkers related to impaired brain growth. Accurate automatic segmentation of neonatal brain MRI is a prerequisite to analyse large datasets. We have previously presented an accurate and robust automatic segmentation technique for parcellating the neonatal brain into multiple cortical and subcortical regions. In this study, we further extend our segmentation method to detect cortical sulci and provide a detailed delineation of the cortical ribbon. These detailed segmentations are used to build a 4-dimensional spatio-temporal structural atlas of the brain for 82 cortical and subcortical structures throughout this developmental period. We employ the algorithm to segment an extensive database of 420 MR images of the developing brain, from 27 to 45 weeks post-menstrual age at imaging. Regional volumetric and cortical surface measurements are derived and used to investigate brain growth and development during this critical period and to assess the impact of immaturity at birth. Whole brain volume, the absolute volume of all structures studied, cortical curvature and cortical surface area increased with increasing age at scan. Relative volumes of cortical grey matter, cerebellum and cerebrospinal fluid increased with age at scan, while relative volumes of white matter, ventricles, brainstem and basal ganglia and thalami decreased. Preterm infants at term had smaller whole brain volumes, reduced regional white matter and cortical and subcortical grey matter volumes, and reduced cortical surface area compared with term born controls, while ventricular volume was greater in the preterm group. Increasing prematurity at birth was associated with a reduction in total and regional white matter, cortical and subcortical grey matter volume, an increase in ventricular volume, and reduced cortical surface area. PMID:26499811

  16. Regional growth and atlasing of the developing human brain.

    PubMed

    Makropoulos, Antonios; Aljabar, Paul; Wright, Robert; Hüning, Britta; Merchant, Nazakat; Arichi, Tomoki; Tusor, Nora; Hajnal, Joseph V; Edwards, A David; Counsell, Serena J; Rueckert, Daniel

    2016-01-15

    Detailed morphometric analysis of the neonatal brain is required to characterise brain development and define neuroimaging biomarkers related to impaired brain growth. Accurate automatic segmentation of neonatal brain MRI is a prerequisite to analyse large datasets. We have previously presented an accurate and robust automatic segmentation technique for parcellating the neonatal brain into multiple cortical and subcortical regions. In this study, we further extend our segmentation method to detect cortical sulci and provide a detailed delineation of the cortical ribbon. These detailed segmentations are used to build a 4-dimensional spatio-temporal structural atlas of the brain for 82 cortical and subcortical structures throughout this developmental period. We employ the algorithm to segment an extensive database of 420 MR images of the developing brain, from 27 to 45weeks post-menstrual age at imaging. Regional volumetric and cortical surface measurements are derived and used to investigate brain growth and development during this critical period and to assess the impact of immaturity at birth. Whole brain volume, the absolute volume of all structures studied, cortical curvature and cortical surface area increased with increasing age at scan. Relative volumes of cortical grey matter, cerebellum and cerebrospinal fluid increased with age at scan, while relative volumes of white matter, ventricles, brainstem and basal ganglia and thalami decreased. Preterm infants at term had smaller whole brain volumes, reduced regional white matter and cortical and subcortical grey matter volumes, and reduced cortical surface area compared with term born controls, while ventricular volume was greater in the preterm group. Increasing prematurity at birth was associated with a reduction in total and regional white matter, cortical and subcortical grey matter volume, an increase in ventricular volume, and reduced cortical surface area. PMID:26499811

  17. Cocaine disposition in discrete regions of rat brain.

    PubMed

    Javaid, J I; Davis, J M

    1993-05-01

    It has been proposed that various effects of psychoactive drugs on the central nervous system may be related to the capacity of the drug to selectively concentrate in specific regions of the brain. In rat brain, cocaine effects on striatal and nucleus accumbens dopaminergic systems show quantitative differences. However, the disposition of cocaine in various brain regions has not been reported. In the present studies we examined the cocaine concentrations over time in serum and discrete brain regions of the rat after single intraperitoneal (i.p.) injection. At different time points (5, 10, 20, 30, 60, 120, and 240 min) after i.p. injection of cocaine hydrochloride (10 mg kg-1, free base) the rats were decapitated and cocaine in serum and various brain regions was quantitated by a specific gas liquid chromatographic method. There was large inter-individual variability in different rats at each time-point. The disposition pattern of cocaine in rats after i.p. administration was similar to that observed in humans after intranasal administration. Initial absorption rate was rapid and, on average, the peak levels of cocaine were achieved in 10 min. The cocaine levels remained relatively high over the next 50 min indicating continual absorption, and then declined with a rate such that the levels 4 h after cocaine administration were undetectable in most of the animals. The overall changes in cocaine levels in various brain regions paralleled the serum concentrations. The area under the cocaine concentration-time curve (AUC) revealed more than three-fold differences in cocaine accumulation in various brain regions. This unequal disposition of cocaine may be responsible in part for differential biochemical effects in different brain regions. PMID:8499585

  18. Auditory brain-stem evoked potentials in cat after kainic acid induced neuronal loss. II. Cochlear nucleus.

    PubMed

    Zaaroor, M; Starr, A

    1991-01-01

    Auditory brain-stem potentials (ABRs) were studied in cats for up to 6 weeks after kainic acid had been injected unilaterally into the cochlear nucleus (CN) producing extensive neuronal destruction. The ABR components were labeled by the polarity at the vertex (P, for positive) and their order of appearance (the arabic numerals 1, 2, etc.). Component P1 can be further subdivided into 2 subcomponents, P1a and P1b. The assumed correspondence between the ABR components in cat and man is indicated by providing human Roman numeral designations in parentheses following the feline notation, e.g., P2 (III). To stimulation of the ear ipsilateral to the injection, the ABR changes consisted of a loss of components P2 (III) and P3 (IV), and an attenuation and prolongation of latency of components P4 (V) and P5 (VI). The sustained potential shift from which the components arose was not affected. Wave P1a (I) was also slightly but significantly attenuated compatible with changes of excitability of nerve VIII in the cochlea secondary to cochlear nucleus destruction. Unexpectedly, to stimulation of the ear contralateral to the injection side, waves P2 (III), P3 (IV), and P4 (V) were also attenuated and delayed in latency but to a lesser degree than to stimulation of the ear ipsilateral to the injection. Changes in binaural interaction of the ABR following cochlear nucleus lesions were similar to those produced in normal animals by introducing a temporal delay of the input to one ear. The results of the present set of studies using kainic acid to induce neuronal loss in auditory pathway when combined with prior lesion and recording experiments suggest that each of the components of the ABR requires the integrity of an anatomically diffuse system comprising a set of neurons, their axons, and the neurons on which they terminate. Disruption of any portion of the system will alter the amplitude and/or the latency of that component. PMID:1716569

  19. Eye movement preparation causes spatially-specific modulation of auditory processing: New evidence from event-related brain potentials

    PubMed Central

    Gherri, Elena; Driver, Jon; Eimer, Martin

    2009-01-01

    To investigate whether saccade preparation can modulate processing of auditory stimuli in a spatially-specific fashion, ERPs were recorded for a Saccade task, in which the direction of a prepared saccade was cued, prior to an imperative auditory stimulus indicating whether to execute or withhold that saccade. For comparison, we also ran a conventional Covert Attention task, where the same cue now indicated the direction for a covert endogenous attentional shift prior to an auditory target-nontarget discrimination. Lateralised components previously observed during cued shifts of attention (ADAN, LDAP) did not differ significantly across tasks, indicating commonalities between auditory spatial attention and oculomotor control. Moreover, in both tasks, spatially-specific modulation of auditory processing was subsequently found, with enhanced negativity for lateral auditory nontarget stimuli at cued versus uncued locations. This modulation started earlier and was more pronounced for the Covert Attention task, but was also reliably present in the Saccade task, demonstrating that the effects of covert saccade preparation on auditory processing can be similar to effects of endogenous covert attentional orienting, albeit smaller. These findings provide new evidence for similarities but also some differences between oculomotor preparation and shifts of endogenous spatial attention. They also show that saccade preparation can affect not just vision, but also sensory processing of auditory events. PMID:18614157

  20. Injured Brain Regions Associated with Anxiety in Vietnam Veterans

    PubMed Central

    Knutson, Kristine M.; Rakowsky, Shana T.; Solomon, Jeffrey; Krueger, Frank; Raymont, Vanessa; Tierney, Michael C.; Wassermann, Eric M.; Grafman, Jordan

    2013-01-01

    Anxiety negatively affects quality of life and psychosocial functioning. Previous research has shown that anxiety symptoms in healthy individuals are associated with variations in the volume of brain regions, such as the amygdala, hippocampus, and the bed nucleus of the stria terminalis. Brain lesion data also suggests the hemisphere damaged may affect levels of anxiety. We studied a sample of 182 male Vietnam War veterans with penetrating brain injuries, using a semi-automated voxel-based lesion-symptom mapping (VLSM) approach. VLSM reveals significant associations between a symptom such as anxiety and the location of brain lesions, and does not require a broad, subjective assignment of patients into categories based on lesion location. We found that lesioned brain regions in cortical and limbic areas of the left hemisphere, including middle, inferior and superior temporal lobe, hippocampus, and fusiform regions, along with smaller areas in the inferior occipital lobe, parahippocampus, amygdala, and insula, were associated with increased anxiety symptoms as measured by the Neurobehavioral Rating Scale (NRS). These results were corroborated by similar findings using Neuropsychiatric Inventory (NPI) anxiety scores, which supports these regions’ role in regulating anxiety. In summary, using a semi-automated analysis tool, we detected an effect of focal brain damage on the presentation of anxiety. We also separated the effects of brain injury and war experience by including a control group of combat veterans without brain injury. We compared this control group against veterans with brain lesions in areas associated with anxiety, and against veterans with lesions only in other brain areas. PMID:23328629

  1. Regional brain hypometabolism is unrelated to regional amyloid plaque burden.

    PubMed

    Altmann, Andre; Ng, Bernard; Landau, Susan M; Jagust, William J; Greicius, Michael D

    2015-12-01

    In its original form, the amyloid cascade hypothesis of Alzheimer's disease holds that fibrillar deposits of amyloid are an early, driving force in pathological events leading ultimately to neuronal death. Early clinicopathological investigations highlighted a number of inconsistencies leading to an updated hypothesis in which amyloid plaques give way to amyloid oligomers as the driving force in pathogenesis. Rather than focusing on the inconsistencies, amyloid imaging studies have tended to highlight the overlap between regions that show early amyloid plaque signal on positron emission tomography and that also happen to be affected early in Alzheimer's disease. Recent imaging studies investigating the regional dependency between metabolism and amyloid plaque deposition have arrived at conflicting results, with some showing regional associations and other not. We extracted multimodal neuroimaging data from the Alzheimer's disease neuroimaging database for 227 healthy controls and 434 subjects with mild cognitive impairment. We analysed regional patterns of amyloid deposition, regional glucose metabolism and regional atrophy using florbetapir ((18)F) positron emission tomography, (18)F-fluordeoxyglucose positron emission tomography and T1-weighted magnetic resonance imaging, respectively. Specifically, we derived grey matter density and standardized uptake value ratios for both positron emission tomography tracers in 404 functionally defined regions of interest. We examined the relation between regional glucose metabolism and amyloid plaques using linear models. For each region of interest, correcting for regional grey matter density, age, education and disease status, we tested the association of regional glucose metabolism with (i) cortex-wide florbetapir uptake; (ii) regional (i.e. in the same region of interest) florbetapir uptake; and (iii) regional florbetapir uptake while correcting in addition for cortex-wide florbetapir uptake. P-values for each setting

  2. Hemodynamic responses in human multisensory and auditory association cortex to purely visual stimulation

    PubMed Central

    Meyer, Martin; Baumann, Simon; Marchina, Sarah; Jancke, Lutz

    2007-01-01

    Background Recent findings of a tight coupling between visual and auditory association cortices during multisensory perception in monkeys and humans raise the question whether consistent paired presentation of simple visual and auditory stimuli prompts conditioned responses in unimodal auditory regions or multimodal association cortex once visual stimuli are presented in isolation in a post-conditioning run. To address this issue fifteen healthy participants partook in a "silent" sparse temporal event-related fMRI study. In the first (visual control) habituation phase they were presented with briefly red flashing visual stimuli. In the second (auditory control) habituation phase they heard brief telephone ringing. In the third (conditioning) phase we coincidently presented the visual stimulus (CS) paired with the auditory stimulus (UCS). In the fourth phase participants either viewed flashes paired with the auditory stimulus (maintenance, CS-) or viewed the visual stimulus in isolation (extinction, CS+) according to a 5:10 partial reinforcement schedule. The participants had no other task than attending to the stimuli and indicating the end of each trial by pressing a button. Results During unpaired visual presentations (preceding and following the paired presentation) we observed significant brain responses beyond primary visual cortex in the bilateral posterior auditory association cortex (planum temporale, planum parietale) and in the right superior temporal sulcus whereas the primary auditory regions were not involved. By contrast, the activity in auditory core regions was markedly larger when participants were presented with auditory stimuli. Conclusion These results demonstrate involvement of multisensory and auditory association areas in perception of unimodal visual stimulation which may reflect the instantaneous forming of multisensory associations and cannot be attributed to sensation of an auditory event. More importantly, we are able to show that brain

  3. Extracellular matrix protein expression is brain region dependent.

    PubMed

    Dauth, Stephanie; Grevesse, Thomas; Pantazopoulos, Harry; Campbell, Patrick H; Maoz, Ben M; Berretta, Sabina; Parker, Kevin Kit

    2016-05-01

    In the brain, extracellular matrix (ECM) components form networks that contribute to structural and functional diversity. Maladaptive remodeling of ECM networks has been reported in neurodegenerative and psychiatric disorders, suggesting that the brain microenvironment is a dynamic structure. A lack of quantitative information about ECM distribution in the brain hinders an understanding of region-specific ECM functions and the role of ECM in health and disease. We hypothesized that each ECM protein as well as specific ECM structures, such as perineuronal nets (PNNs) and interstitial matrix, are differentially distributed throughout the brain, contributing to the unique structure and function in the various regions of the brain. To test our hypothesis, we quantitatively analyzed the distribution, colocalization, and protein expression of aggrecan, brevican, and tenascin-R throughout the rat brain utilizing immunohistochemistry and mass spectrometry analysis and assessed the effect of aggrecan, brevican, and/or tenascin-R on neurite outgrowth in vitro. We focused on aggrecan, brevican, and tenascin-R as they are especially expressed in the mature brain, and have established roles in brain development, plasticity, and neurite outgrowth. The results revealed a differentiated distribution of all three proteins throughout the brain and indicated that their presence significantly reduces neurite outgrowth in a 3D in vitro environment. These results underline the importance of a unique and complex ECM distribution for brain physiology and suggest that encoding the distribution of distinct ECM proteins throughout the brain will aid in understanding their function in physiology and in turn assist in identifying their role in disease. J. Comp. Neurol. 524:1309-1336, 2016. © 2016 Wiley Periodicals, Inc. PMID:26780384

  4. Attention Modulates the Auditory Cortical Processing of Spatial and Category Cues in Naturalistic Auditory Scenes

    PubMed Central

    Renvall, Hanna; Staeren, Noël; Barz, Claudia S.; Ley, Anke; Formisano, Elia

    2016-01-01

    This combined fMRI and MEG study investigated brain activations during listening and attending to natural auditory scenes. We first recorded, using in-ear microphones, vocal non-speech sounds, and environmental sounds that were mixed to construct auditory scenes containing two concurrent sound streams. During the brain measurements, subjects attended to one of the streams while spatial acoustic information of the scene was either preserved (stereophonic sounds) or removed (monophonic sounds). Compared to monophonic sounds, stereophonic sounds evoked larger blood-oxygenation-level-dependent (BOLD) fMRI responses in the bilateral posterior superior temporal areas, independent of which stimulus attribute the subject was attending to. This finding is consistent with the functional role of these regions in the (automatic) processing of auditory spatial cues. Additionally, significant differences in the cortical activation patterns depending on the target of attention were observed. Bilateral planum temporale and inferior frontal gyrus were preferentially activated when attending to stereophonic environmental sounds, whereas when subjects attended to stereophonic voice sounds, the BOLD responses were larger at the bilateral middle superior temporal gyrus and sulcus, previously reported to show voice sensitivity. In contrast, the time-resolved MEG responses were stronger for mono- than stereophonic sounds in the bilateral auditory cortices at ~360 ms after the stimulus onset when attending to the voice excerpts within the combined sounds. The observed effects suggest that during the segregation of auditory objects from the auditory background, spatial sound cues together with other relevant temporal and spectral cues are processed in an attention-dependent manner at the cortical locations generally involved in sound recognition. More synchronous neuronal activation during monophonic than stereophonic sound processing, as well as (local) neuronal inhibitory mechanisms in

  5. Regional distributions of brain glutamate and glutamine in normal subjects.

    PubMed

    Goryawala, Mohammed Z; Sheriff, Sulaiman; Maudsley, Andrew A

    2016-08-01

    Glutamate (Glu) and glutamine (Gln) play an important role in neuronal regulation and are of value as MRS-observable diagnostic biomarkers. In this study the relative concentrations of these metabolites have been measured in multiple regions in the normal brain using a short-TE whole-brain MRSI measurement at 3 T combined with a modified data analysis approach that used spatial averaging to obtain high-SNR spectra from atlas-registered anatomic regions or interest. By spectral fitting of high-SNR spectra this approach yielded reliable measurements across a wide volume of the brain. Spectral averaging also demonstrated increased SNR and improved fitting accuracy for the sum of Glu and Gln (Glx) compared with individual voxel fitting. Results in 26 healthy controls showed relatively constant Glu/Cr and Gln/Cr throughout the cerebrum, although with increased values in the anterior cingulum and paracentral lobule, and increased Gln/Cr in the superior motor area. The deep gray-matter regions of thalamus, putamen, and pallidum show lower Glu/Cr compared with cortical white-matter regions. Lobar measurements demonstrated reduced Glu/Cr and Gln/Cr in the cerebellum as compared with the cerebrum, where white-matter regions show significantly lower Glu/Cr and Gln/Cr as compared with gray-matter regions across multiple brain lobes. Regression analysis showed no significant effect of gender on Glu/Cr or Gln/Cr measurement; however, Glx/Cr ratio was found to be significantly negatively correlated with age in some lobar brain regions. In summary, this methodology provides the spectral quality necessary for reliable separation of Glu and Gln at 3 T from a single MRSI acquisition enabling generation of regional distributions of metabolites over a large volume of the brain, including cortical regions. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27351339

  6. Grey matter connectivity within and between auditory, language and visual systems in prelingually deaf adolescents

    PubMed Central

    Li, Wenjing; Li, Jianhong; Wang, Zhenchang; Li, Yong; Liu, Zhaohui; Yan, Fei; Xian, Junfang; He, Huiguang

    2015-01-01

    Abstract Purpose: Previous studies have shown brain reorganizations after early deprivation of auditory sensory. However, changes of grey matter connectivity have not been investigated in prelingually deaf adolescents yet. In the present study, we aimed to investigate changes of grey matter connectivity within and between auditory, language and visual systems in prelingually deaf adolescents. Methods: We recruited 16 prelingually deaf adolescents and 16 age-and gender-matched normal controls, and extracted the grey matter volume as the structural characteristic from 14 regions of interest involved in auditory, language or visual processing to investigate the changes of grey matter connectivity within and between auditory, language and visual systems. Sparse inverse covariance estimation (SICE) was utilized to construct grey matter connectivity between these brain regions. Results: The results show that prelingually deaf adolescents present weaker grey matter connectivity within auditory and visual systems, and connectivity between language and visual systems declined. Notably, significantly increased brain connectivity was found between auditory and visual systems in prelingually deaf adolescents. Conclusions: Our results indicate “cross-modal” plasticity after deprivation of the auditory input in prelingually deaf adolescents, especially between auditory and visual systems. Besides, auditory deprivation and visual deficits might affect the connectivity pattern within language and visual systems in prelingually deaf adolescents. PMID:25698109

  7. The role of auditory transient and deviance processing in distraction of task performance: a combined behavioral and event-related brain potential study.

    PubMed

    Berti, Stefan

    2013-01-01

    Distraction of goal-oriented performance by a sudden change in the auditory environment is an everyday life experience. Different types of changes can be distracting, including a sudden onset of a transient sound and a slight deviation of otherwise regular auditory background stimulation. With regard to deviance detection, it is assumed that slight changes in a continuous sequence of auditory stimuli are detected by a predictive coding mechanisms and it has been demonstrated that this mechanism is capable of distracting ongoing task performance. In contrast, it is open whether transient detection-which does not rely on predictive coding mechanisms-can trigger behavioral distraction, too. In the present study, the effect of rare auditory changes on visual task performance is tested in an auditory-visual cross-modal distraction paradigm. The rare changes are either embedded within a continuous standard stimulation (triggering deviance detection) or are presented within an otherwise silent situation (triggering transient detection). In the event-related brain potentials, deviants elicited the mismatch negativity (MMN) while transients elicited an enhanced N1 component, mirroring pre-attentive change detection in both conditions but on the basis of different neuro-cognitive processes. These sensory components are followed by attention related ERP components including the P3a and the reorienting negativity (RON). This demonstrates that both types of changes trigger switches of attention. Finally, distraction of task performance is observable, too, but the impact of deviants is higher compared to transients. These findings suggest different routes of distraction allowing for the automatic processing of a wide range of potentially relevant changes in the environment as a pre-requisite for adaptive behavior. PMID:23874278

  8. Evidence of a visual-to-auditory cross-modal sensory gating phenomenon as reflected by the human P50 event-related brain potential modulation.

    PubMed

    Lebib, Riadh; Papo, David; de Bode, Stella; Baudonnière, Pierre Marie

    2003-05-01

    We investigated the existence of a cross-modal sensory gating reflected by the modulation of an early electrophysiological index, the P50 component. We analyzed event-related brain potentials elicited by audiovisual speech stimuli manipulated along two dimensions: congruency and discriminability. The results showed that the P50 was attenuated when visual and auditory speech information were redundant (i.e. congruent), in comparison with this same event-related potential component elicited with discrepant audiovisual dubbing. When hard to discriminate, however, bimodal incongruent speech stimuli elicited a similar pattern of P50 attenuation. We concluded to the existence of a visual-to-auditory cross-modal sensory gating phenomenon. These results corroborate previous findings revealing a very early audiovisual interaction during speech perception. Finally, we postulated that the sensory gating system included a cross-modal dimension. PMID:12697279

  9. Conventional and cross-correlation brain-stem auditory evoked responses in the white leghorn chick: rate manipulations

    NASA Technical Reports Server (NTRS)

    Burkard, R.; Jones, S.; Jones, T.

    1994-01-01

    Rate-dependent changes in the chick brain-stem auditory evoked response (BAER) using conventional averaging and a cross-correlation technique were investigated. Five 15- to 19-day-old white leghorn chicks were anesthetized with Chloropent. In each chick, the left ear was acoustically stimulated. Electrical pulses of 0.1-ms duration were shaped, attenuated, and passed through a current driver to an Etymotic ER-2 which was sealed in the ear canal. Electrical activity from stainless-steel electrodes was amplified, filtered (300-3000 Hz) and digitized at 20 kHz. Click levels included 70 and 90 dB peSPL. In each animal, conventional BAERs were obtained at rates ranging from 5 to 90 Hz. BAERs were also obtained using a cross-correlation technique involving pseudorandom pulse sequences called maximum length sequences (MLSs). The minimum time between pulses, called the minimum pulse interval (MPI), ranged from 0.5 to 6 ms. Two BAERs were obtained for each condition. Dependent variables included the latency and amplitude of the cochlear microphonic (CM), wave 2 and wave 3. BAERs were observed in all chicks, for all level by rate combinations for both conventional and MLS BAERs. There was no effect of click level or rate on the latency of the CM. The latency of waves 2 and 3 increased with decreasing click level and increasing rate. CM amplitude decreased with decreasing click level, but was not influenced by click rate for the 70 dB peSPL condition. For the 90 dB peSPL click, CM amplitude was uninfluenced by click rate for conventional averaging. For MLS BAERs, CM amplitude was similar to conventional averaging for longer MPIs.(ABSTRACT TRUNCATED AT 250 WORDS).

  10. An fMRI Study of Auditory Orienting and Inhibition of Return in Pediatric Mild Traumatic Brain Injury

    PubMed Central

    Yang, Zhen; Yeo, Ronald A.; Pena, Amanda; Ling, Josef M.; Klimaj, Stefan; Campbell, Richard; Doezema, David

    2012-01-01

    Abstract Studies in adult mild traumatic brain injury (mTBI) have shown that two key measures of attention, spatial reorienting and inhibition of return (IOR), are impaired during the first few weeks of injury. However, it is currently unknown whether similar deficits exist following pediatric mTBI. The current study used functional magnetic resonance imaging (fMRI) to investigate the effects of semi-acute mTBI (<3 weeks post-injury) on auditory orienting in 14 pediatric mTBI patients (age 13.50±1.83 years; education: 6.86±1.88 years), and 14 healthy controls (age 13.29±2.09 years; education: 7.21±2.08 years), matched for age and years of education. The results indicated that patients with mTBI showed subtle (i.e., moderate effect sizes) but non-significant deficits on formal neuropsychological testing and during IOR. In contrast, functional imaging results indicated that patients with mTBI demonstrated significantly decreased activation within the bilateral posterior cingulate gyrus, thalamus, basal ganglia, midbrain nuclei, and cerebellum. The spatial topography of hypoactivation was very similar to our previous study in adults, suggesting that subcortical structures may be particularly affected by the initial biomechanical forces in mTBI. Current results also suggest that fMRI may be a more sensitive tool for identifying semi-acute effects of mTBI than the procedures currently used in clinical practice, such as neuropsychological testing and structural scans. fMRI findings could potentially serve as a biomarker for measuring the subtle injury caused by mTBI, and documenting the course of recovery. PMID:22533632

  11. Central auditory disorders: toward a neuropsychology of auditory objects

    PubMed Central

    Goll, Johanna C.; Crutch, Sebastian J.; Warren, Jason D.

    2012-01-01

    Purpose of review Analysis of the auditory environment, source identification and vocal communication all require efficient brain mechanisms for disambiguating, representing and understanding complex natural sounds as ‘auditory objects’. Failure of these mechanisms leads to a diverse spectrum of clinical deficits. Here we review current evidence concerning the phenomenology, mechanisms and brain substrates of auditory agnosias and related disorders of auditory object processing. Recent findings Analysis of lesions causing auditory object deficits has revealed certain broad anatomical correlations: deficient parsing of the auditory scene is associated with lesions involving the parieto-temporal junction, while selective disorders of sound recognition occur with more anterior temporal lobe or extra-temporal damage. Distributed neural networks have been increasingly implicated in the pathogenesis of such disorders as developmental dyslexia, congenital amusia and tinnitus. Auditory category deficits may arise from defective interaction of spectrotemporal encoding and executive and mnestic processes. Dedicated brain mechanisms are likely to process specialised sound objects such as voices and melodies. Summary Emerging empirical evidence suggests a clinically relevant, hierarchical and fractionated neuropsychological model of auditory object processing that provides a framework for understanding auditory agnosias and makes specific predictions to direct future work. PMID:20975559

  12. Regional brain glucose metabolism in patients with brain tumors before and after radiotherapy

    SciTech Connect

    Wang, G.J.; Volkow, N.D.; Lau, Y.H.

    1994-05-01

    This study was performed to measure regional glucose metabolism in nonaffected brain regions of patients with primary or metastatic brain tumors. Seven female and four male patients (mean age 51.5{plus_minus}14.0 years old) were compared with eleven age and sex matched normal subjects. None of the patients had hydrocephalus and/or increased intracranial pressure. Brain glucose metabolism was measured using FDG-PET scan. Five of the patients were reevaluated one week after receiving radiation treatment (RT) to the brain. Patients were on Decadron and/or Dilantin at the time of both scan. PET images were analyzed with a template of 115 nonoverlapping regions of interest and then grouped into eight gray matter regions on each hemisphere. Brain regions with tumors and edema shown in MR imaging were excluded. Z scores were used to compare individual patients` regional values with those of normal subjects. The number of regional values with Z scores of less than - 3.0 were considered abnormal and were quantified. The mean global glucose metabolic rate (mean of all regions) in nonaffected brain regions of patients was significantly lower than that of normal controls (32.1{plus_minus}9.0 versus 44.8{plus_minus}6.3 {mu}mol/100g/min, p<0.001). Analyses of individual subjects revealed that none of the controls and 8 of the 11 patients had at least one abnormal region. In these 8 patients the regions which were abnormal were most frequently localized in right (n=5) and left occipital (n=6) and right orbital frontal cortex (n=7) whereas the basal ganglia was not affected. Five of the patients who had repeated scans following RT showed decrements in tumor metabolism (41{plus_minus}20.5%) and a significant increase in whole brain metabolism (8.6{plus_minus}5.3%, p<0.001). The improvement in whole brain metabolism after RT suggests that the brain metabolic decrements in the patients were related to the presence of tumoral tissue and not just a medication effect.

  13. Reproducibility of regional brain metabolic responses to lorazepam

    SciTech Connect

    Wang, G.J.; Volkow, N.D.; Overall, J. |

    1996-10-01

    Changes in regional brain glucose metabolism in response to benzodiazepine agonists have been used as indicators of benzodiazepine-GABA receptor function. The purpose of this study was to assess the reproducibility of these responses. Sixteen healthy right-handed men underwent scanning with PET and [{sup 18}F]fluorodeoxyglucose (FDG) twice: before placebo and before lorazepam (30 {mu}g/kg). The same double FDG procedure was repeated 6-8 wk later on the men to assess test-retest reproducibility. The regional absolute brain metabolic values obtained during the second evaluation were significantly lower than those obtained from the first evaluation regardless of condition (p {le} 0.001). Lorazepam significantly and consistently decreased both whole-brain metabolism and the magnitude. The regional pattern of the changes were comparable for both studies (12.3% {plus_minus} 6.9% and 13.7% {plus_minus} 7.4%). Lorazepam effects were the largest in the thalamus (22.2% {plus_minus} 8.6% and 22.4% {plus_minus} 6.9%) and occipital cortex (19% {plus_minus} 8.9% and 21.8% {plus_minus} 8.9%). Relative metabolic measures were highly reproducible both for pharmacolgic and replication condition. This study measured the test-retest reproducibility in regional brain metabolic responses, and although the global and regional metabolic values were significantly lower for the repeated evaluation, the response to lorazepam was highly reproducible. 1613 refs., 3 figs., 3 tabs.

  14. Extracting regional brain patterns for classification of neurodegenerative diseases

    NASA Astrophysics Data System (ADS)

    Pulido, Andrea; Rueda, Andrea; Romero, Eduardo

    2013-11-01

    In structural Magnetic Resonance Imaging (MRI), neurodegenerative diseases generally present complex brain patterns that can be correlated with di erent clinical onsets of this pathologies. An objective method that aims to determine both global and local changes is not usually available in clinical practice, thus the interpretation of these images is strongly dependent on the radiologist's skills. In this paper, we propose a strategy which interprets the brain structure using a framework that highlights discriminant brain patterns for neurodegenerative diseases. This is accomplished by combining a probabilistic learning technique, which identi es and groups regions with similar visual features, with a visual saliency method that exposes relevant information within each region. The association of such patterns with a speci c disease is herein evaluated in a classi cation task, using a dataset including 80 Alzheimer's disease (AD) patients and 76 healthy subjects (NC). Preliminary results show that the proposed method reaches a maximum classi cation accuracy of 81.39%.

  15. Organization of projection neurons and local neurons of the primary auditory center in the fruit fly Drosophila melanogaster.

    PubMed

    Matsuo, Eriko; Seki, Haruyoshi; Asai, Tomonori; Morimoto, Takako; Miyakawa, Hiroyoshi; Ito, Kei; Kamikouchi, Azusa

    2016-04-15

    Acoustic communication between insects serves as an excellent model system for analyzing the neuronal mechanisms underlying auditory information processing. The detailed organization of auditory neural circuits in the brain has not yet been described. To understand the central auditory pathways, we used the brain of the fruit fly Drosophila melanogaster as a model and performed a large-scale analysis of the interneurons associated with the primary auditory center. By screening expression driver strains and performing single-cell labeling of these strains, we identified 44 types of interneurons innervating the primary auditory center. Five types were local interneurons whereas the other 39 types were projection interneurons connecting the primary auditory center with other brain regions. The projection neurons comprised three frequency-selective pathways and two frequency-embracive pathways. Mapping of their connection targets revealed that five neuropils in the brain-the wedge (WED), anterior ventrolateral protocerebrum, posterior ventrolateral protocerebrum (PVLP), saddle (SAD), and gnathal ganglia (GNG)-were intensively connected with the primary auditory center. In addition, several other neuropils, including visual and olfactory centers in the brain, were directly connected to the primary auditory center. The distribution patterns of the spines and boutons of the identified neurons suggest that auditory information is sent mainly from the primary auditory center to the PVLP, WED, SAD, GNG, and thoracico-abdominal ganglia. Based on these findings, we established the first comprehensive map of secondary auditory interneurons, which indicates the downstream information flow to parallel ascending pathways, multimodal pathways, and descending pathways. J. Comp. Neurol. 524:1099-1164, 2016. © 2016 Wiley Periodicals, Inc. PMID:26854012

  16. Early life stress affects limited regional brain activity in depression

    PubMed Central

    Du, Lian; Wang, Jingjie; Meng, Ben; Yong, Na; Yang, Xiangying; Huang, Qingling; Zhang, Yan; Yang, Lingling; Qu, Yuan; Chen, Zhu; Li, Yongmei; Lv, Fajin; Hu, Hua

    2016-01-01

    Early life stress (ELS) can alter brain function and increases the risk of major depressive disorder (MDD) in later life. This study investigated whether ELS contributes to differences in regional brain activity between MDD patients and healthy controls (HC), as measured by amplitude of low-frequency fluctuation (ALFF)/fractional (f)ALFF. Eighteen first-episode, treatment-naïve MDD patients and HC were assessed with the Childhood Trauma Questionnaire and resting-state functional magnetic resonance imaging. We compared ALFF/fALFF between MDD patients and HC, with or without controlling for ELS, and determined whether ELS level was correlated with regional brain activity in each group. After regressing out ELS, we found that ALFF increased in bilateral amygdala and left orbital/cerebellum, while fALFF decreased in left inferior temporal and right middle frontal gyri in MDD patients relative to controls. ELS positively correlated with regional activity in the left cerebellum in MDD and in the right post-central/inferior temporal/superior frontal cingulate, inferior frontal gyrus and bilateral cerebellum in HC. Our findings indicate that there is only very limited region showing correlation between ELS and brain activity in MDD, while diverse areas in HC, suggesting ELS has few impacts on MDD patients. PMID:27138376

  17. Brain Regions Underlying Word Finding Difficulties in Temporal Lobe Epilepsy

    ERIC Educational Resources Information Center

    Trebuchon-Da Fonseca, Agnes; Guedj, Eric; Alario, F-Xavier; Laguitton, Virginie; Mundler, Olivier; Chauvel, Patrick; Liegeois-Chauvel, Catherine

    2009-01-01

    Word finding difficulties are often reported by epileptic patients with seizures originating from the language dominant cerebral hemisphere, for example, in temporal lobe epilepsy. Evidence regarding the brain regions underlying this deficit comes from studies of peri-operative electro-cortical stimulation, as well as post-surgical performance.…

  18. Cognitive Abilities Independent of IQ Correlate with Regional Brain Structure

    ERIC Educational Resources Information Center

    Johnson, Wendy; Jung, Rex E.; Colom, Roberto; Haier, Richard J.

    2008-01-01

    There is increasing evidence relating psychometric measures of general intelligence and reasoning to regional brain structure and function assessed with a variety of neuroimaging techniques. Cognitive dimensions independent of general intelligence can also be identified psychometrically and studied for any neuroanatomical correlates. Here we…

  19. Cross-Modal Plasticity in Higher-Order Auditory Cortex of Congenitally Deaf Cats Does Not Limit Auditory Responsiveness to Cochlear Implants

    PubMed Central

    Baumhoff, Peter; Tillein, Jochen; Lomber, Stephen G.; Hubka, Peter; Kral, Andrej

    2016-01-01

    Congenital sensory deprivation can lead to reorganization of the deprived cortical regions by another sensory system. Such cross-modal reorganization may either compete with or complement the “original“ inputs to the deprived area after sensory restoration and can thus be either adverse or beneficial for sensory restoration. In congenital deafness, a previous inactivation study documented that supranormal visual behavior was mediated by higher-order auditory fields in congenitally deaf cats (CDCs). However, both the auditory responsiveness of “deaf” higher-order fields and interactions between the reorganized and the original sensory input remain unknown. Here, we studied a higher-order auditory field responsible for the supranormal visual function in CDCs, the auditory dorsal zone (DZ). Hearing cats and visual cortical areas served as a control. Using mapping with microelectrode arrays, we demonstrate spatially scattered visual (cross-modal) responsiveness in the DZ, but show that this did not interfere substantially with robust auditory responsiveness elicited through cochlear implants. Visually responsive and auditory-responsive neurons in the deaf auditory cortex formed two distinct populations that did not show bimodal interactions. Therefore, cross-modal plasticity in the deaf higher-order auditory cortex had limited effects on auditory inputs. The moderate number of scattered cross-modally responsive neurons could be the consequence of exuberant connections formed during development that were not pruned postnatally in deaf cats. Although juvenile brain circuits are modified extensively by experience, the main driving input to the cross-modally (visually) reorganized higher-order auditory cortex remained auditory in congenital deafness. SIGNIFICANCE STATEMENT In a common view, the “unused” auditory cortex of deaf individuals is reorganized to a compensatory sensory function during development. According to this view, cross-modal plasticity takes

  20. Loss of auditory sensitivity from inner hair cell synaptopathy can be centrally compensated in the young but not old brain.

    PubMed

    Möhrle, Dorit; Ni, Kun; Varakina, Ksenya; Bing, Dan; Lee, Sze Chim; Zimmermann, Ulrike; Knipper, Marlies; Rüttiger, Lukas

    2016-08-01

    A dramatic shift in societal demographics will lead to rapid growth in the number of older people with hearing deficits. Poorer performance in suprathreshold speech understanding and temporal processing with age has been previously linked with progressing inner hair cell (IHC) synaptopathy that precedes age-dependent elevation of auditory thresholds. We compared central sound responsiveness after acoustic trauma in young, middle-aged, and older rats. We demonstrate that IHC synaptopathy progresses from middle age onward and hearing threshold becomes elevated from old age onward. Interestingly, middle-aged animals could centrally compensate for the loss of auditory fiber activity through an increase in late auditory brainstem responses (late auditory brainstem response wave) linked to shortening of central response latencies. In contrast, old animals failed to restore central responsiveness, which correlated with reduced temporal resolution in responding to amplitude changes. These findings may suggest that cochlear IHC synaptopathy with age does not necessarily induce temporal auditory coding deficits, as long as the capacity to generate neuronal gain maintains normal sound-induced central amplitudes. PMID:27318145

  1. Influence of ketamine on regional brain glucose use

    SciTech Connect

    Davis, D.W.; Mans, A.M.; Biebuyck, J.F.; Hawkins, R.A.

    1988-08-01

    The purpose of this study was to determine the effect of different doses of ketamine on cerebral function at the level of individual brain structures as reflected by glucose use. Rats received either 5 or 30 mg/kg ketamine intravenously as a loading dose, followed by an infusion to maintain a steady-state level of the drug. An additional group received 30 mg/kg as a single injection only, and was studied 20 min later, by which time they were recovering consciousness (withdrawal group). Regional brain energy metabolism was evaluated with (6-/sup 14/C)glucose and quantitative autoradiography during a 5-min experimental period. A subhypnotic, steady-state dose (5 mg/kg) of ketamine caused a stimulation of glucose use in most brain areas, with an average increase of 20%. At the larger steady-state dose (30 mg/kg, which is sufficient to cause anesthesia), there was no significant effect on most brain regions; some sensory nuclei were depressed (inferior colliculus, -29%; cerebellar dentate nucleus, -18%; vestibular nucleus, -16%), but glucose use in the ventral posterior hippocampus was increased by 33%. In contrast, during withdrawal from a 30-mg/kg bolus, there was a stimulation of glucose use throughout the brain (21-78%), at a time when plasma ketamine levels were similar to the levels in the 5 mg/kg group. At each steady-state dose, as well as during withdrawal, ketamine caused a notable stimulation of glucose use by the hippocampus.

  2. Regional brain stiffness changes across the Alzheimer's disease spectrum☆

    PubMed Central

    Murphy, Matthew C.; Jones, David T.; Jack, Clifford R.; Glaser, Kevin J.; Senjem, Matthew L.; Manduca, Armando; Felmlee, Joel P.; Carter, Rickey E.; Ehman, Richard L.; Huston, John

    2015-01-01

    Magnetic resonance elastography (MRE) is an MRI-based technique to noninvasively measure tissue stiffness. Currently well established for clinical use in the liver, MRE is increasingly being investigated to measure brain stiffness as a novel biomarker of a variety of neurological diseases. The purpose of this work was to apply a recently developed MRE pipeline to measure regional brain stiffness changes in human subjects across the Alzheimer's disease (AD) spectrum, and to gain insights into the biological processes underlying those stiffness changes by correlating stiffness with existing biomarkers of AD. The results indicate that stiffness changes occur mostly in the frontal, parietal and temporal lobes, in accordance with the known topography of AD pathology. Furthermore, stiffness in those areas correlates with existing imaging biomarkers of AD including hippocampal volumes and amyloid PET. Additional analysis revealed preliminary but significant evidence that the relationship between brain stiffness and AD severity is nonlinear and non-monotonic. Given that similar relationships have been observed in functional MRI experiments, we used task-free fMRI data to test the hypothesis that brain stiffness was sensitive to structural changes associated with altered functional connectivity. The analysis revealed that brain stiffness is significantly and positively correlated with default mode network connectivity. Therefore, brain stiffness as measured by MRE has potential to provide new and essential insights into the temporal dynamics of AD, as well as the relationship between functional and structural plasticity as it relates to AD pathophysiology. PMID:26900568

  3. Flexible information coding in human auditory cortex during perception, imagery, and STM of complex sounds.

    PubMed

    Linke, Annika C; Cusack, Rhodri

    2015-07-01

    Auditory cortex is the first cortical region of the human brain to process sounds. However, it has recently been shown that its neurons also fire in the absence of direct sensory input, during memory maintenance and imagery. This has commonly been taken to reflect neural coding of the same acoustic information as during the perception of sound. However, the results of the current study suggest that the type of information encoded in auditory cortex is highly flexible. During perception and memory maintenance, neural activity patterns are stimulus specific, reflecting individual sound properties. Auditory imagery of the same sounds evokes similar overall activity in auditory cortex as perception. However, during imagery abstracted, categorical information is encoded in the neural patterns, particularly when individuals are experiencing more vivid imagery. This highlights the necessity to move beyond traditional "brain mapping" inference in human neuroimaging, which assumes common regional activation implies similar mental representations. PMID:25603030

  4. Volumetric comparison of auditory brain nuclei in ear-tufted Araucanas with those in other chicken breeds.

    PubMed

    Frahm, H D; Rehkämper, G

    1998-01-01

    Domestic chickens of the breed Araucana have ear-tufts, which affect the structure of the ear canal. Volumes of auditory brainstem nuclei were measured in three chicken breeds in order to evaluate whether the characteristics described for ear-tufted individuals of the Araucana chicken breed (alterations in the outer and middle ear anatomy) are associated with changes in the size of the relevant auditory nuclei. Allometric comparison reveals no size reductions of the angular, laminar and superior olivary nuclei in Araucanas, compared to Japanese Bantams and Brown Leghorns, but a slight increase in the size of the magnocellular nucleus. PMID:9672109

  5. Modulation of Auditory Spatial Attention by Angry Prosody: An fMRI Auditory Dot-Probe Study.

    PubMed

    Ceravolo, Leonardo; Frühholz, Sascha; Grandjean, Didier

    2016-01-01

    Emotional stimuli have been shown to modulate attentional orienting through signals sent by subcortical brain regions that modulate visual perception at early stages of processing. Fewer studies, however, have investigated a similar effect of emotional stimuli on attentional orienting in the auditory domain together with an investigation of brain regions underlying such attentional modulation, which is the general aim of the present study. Therefore, we used an original auditory dot-probe paradigm involving simultaneously presented neutral and angry non-speech vocal utterances lateralized to either the left or the right auditory space, immediately followed by a short and lateralized single sine wave tone presented in the same (valid trial) or in the opposite space as the preceding angry voice (invalid trial). Behavioral results showed an expected facilitation effect for target detection during valid trials while functional data showed greater activation in the middle and posterior superior temporal sulci (STS) and in the medial frontal cortex for valid vs. invalid trials. The use of reaction time facilitation [absolute value of the Z-score of valid-(invalid+neutral)] as a group covariate extended enhanced activity in the amygdalae, auditory thalamus, and visual cortex. Taken together, our results suggest the involvement of a large and distributed network of regions among which the STS, thalamus, and amygdala are crucial for the decoding of angry prosody, as well as for orienting and maintaining attention within an auditory space that was previously primed by a vocal emotional event. PMID:27242420

  6. Modulation of Auditory Spatial Attention by Angry Prosody: An fMRI Auditory Dot-Probe Study

    PubMed Central

    Ceravolo, Leonardo; Frühholz, Sascha; Grandjean, Didier

    2016-01-01

    Emotional stimuli have been shown to modulate attentional orienting through signals sent by subcortical brain regions that modulate visual perception at early stages of processing. Fewer studies, however, have investigated a similar effect of emotional stimuli on attentional orienting in the auditory domain together with an investigation of brain regions underlying such attentional modulation, which is the general aim of the present study. Therefore, we used an original auditory dot-probe paradigm involving simultaneously presented neutral and angry non-speech vocal utterances lateralized to either the left or the right auditory space, immediately followed by a short and lateralized single sine wave tone presented in the same (valid trial) or in the opposite space as the preceding angry voice (invalid trial). Behavioral results showed an expected facilitation effect for target detection during valid trials while functional data showed greater activation in the middle and posterior superior temporal sulci (STS) and in the medial frontal cortex for valid vs. invalid trials. The use of reaction time facilitation [absolute value of the Z-score of valid-(invalid+neutral)] as a group covariate extended enhanced activity in the amygdalae, auditory thalamus, and visual cortex. Taken together, our results suggest the involvement of a large and distributed network of regions among which the STS, thalamus, and amygdala are crucial for the decoding of angry prosody, as well as for orienting and maintaining attention within an auditory space that was previously primed by a vocal emotional event. PMID:27242420

  7. Co-speech gestures influence neural activity in brain regions associated with processing semantic information.

    PubMed

    Dick, Anthony Steven; Goldin-Meadow, Susan; Hasson, Uri; Skipper, Jeremy I; Small, Steven L

    2009-11-01

    Everyday communication is accompanied by visual information from several sources, including co-speech gestures, which provide semantic information listeners use to help disambiguate the speaker's message. Using fMRI, we examined how gestures influence neural activity in brain regions associated with processing semantic information. The BOLD response was recorded while participants listened to stories under three audiovisual conditions and one auditory-only (speech alone) condition. In the first audiovisual condition, the storyteller produced gestures that naturally accompany speech. In the second, the storyteller made semantically unrelated hand movements. In the third, the storyteller kept her hands still. In addition to inferior parietal and posterior superior and middle temporal regions, bilateral posterior superior temporal sulcus and left anterior inferior frontal gyrus responded more strongly to speech when it was further accompanied by gesture, regardless of the semantic relation to speech. However, the right inferior frontal gyrus was sensitive to the semantic import of the hand movements, demonstrating more activity when hand movements were semantically unrelated to the accompanying speech. These findings show that perceiving hand movements during speech modulates the distributed pattern of neural activation involved in both biological motion perception and discourse comprehension, suggesting listeners attempt to find meaning, not only in the words speakers produce, but also in the hand movements that accompany speech. PMID:19384890

  8. Common DNA methylation alterations in multiple brain regions in autism

    PubMed Central

    Ladd-Acosta, Christine; Hansen, Kasper D.; Briem, Eirikur; Fallin, M. Daniele; Kaufmann, Walter E.; Feinberg, Andrew P.

    2014-01-01

    Autism spectrum disorders (ASD) are increasingly common neurodevelopmental disorders defined clinically by a triad of features including impairment in social interaction, impairment in communication in social situations, and restricted and repetitive patterns of behavior and interests, with considerable phenotypic heterogeneity among individuals. Although heritability estimates for ASD are high, conventional genetic-based efforts to identify genes involved in ASD have yielded only few reproducible candidate genes that account for only a small proportion of ASDs. There is mounting evidence to suggest environmental and epigenetic factors play a stronger role in the etiology of ASD than previously thought. To begin to understand the contribution of epigenetics to ASD, we have examined DNA methylation (DNAm) in a pilot study of post-mortem brain tissue from 19 autism cases and 21 unrelated controls, among three brain regions including dorsolateral prefrontal cortex, temporal cortex, and cerebellum. We measured over 485,000 CpG loci across a diverse set of functionally relevant genomic regions using the Infinium HumanMethylation450 BeadChip and identified 4 genome-wide significant differentially methylated regions (DMRs) using a novel bumphunting approach and a permutation-based multiple testing correction method. We replicated 3/4 DMRs identified in our genome-wide screen in a different set of samples and across different brain regions. The DMRs identified in this study represent suggestive evidence for commonly altered methylation sites in ASD and provide several promising new candidate genes. PMID:23999529

  9. The Role of Animacy in the Real Time Comprehension of Mandarin Chinese: Evidence from Auditory Event-Related Brain Potentials

    ERIC Educational Resources Information Center

    Philipp, Markus; Bornkessel-Schlesewsky, Ina; Bisang, Walter; Schlesewsky, Matthias

    2008-01-01

    Two auditory ERP studies examined the role of animacy in sentence comprehension in Mandarin Chinese by comparing active and passive sentences in simple verb-final (Experiment 1) and relative clause constructions (Experiment 2). In addition to the voice manipulation (which modulated the assignment of actor and undergoer roles to the arguments),…

  10. Characterization of auditory synaptic inputs to gerbil perirhinal cortex.

    PubMed

    Kotak, Vibhakar C; Mowery, Todd M; Sanes, Dan H

    2015-01-01

    The representation of acoustic cues involves regions downstream from the auditory cortex (ACx). One such area, the perirhinal cortex (PRh), processes sensory signals containing mnemonic information. Therefore, our goal was to assess whether PRh receives auditory inputs from the auditory thalamus (MG) and ACx in an auditory thalamocortical brain slice preparation and characterize these afferent-driven synaptic properties. When the MG or ACx was electrically stimulated, synaptic responses were recorded from the PRh neurons. Blockade of type A gamma-aminobutyric acid (GABA-A) receptors dramatically increased the amplitude of evoked excitatory potentials. Stimulation of the MG or ACx also evoked calcium transients in most PRh neurons. Separately, when fluoro ruby was injected in ACx in vivo, anterogradely labeled axons and terminals were observed in the PRh. Collectively, these data show that the PRh integrates auditory information from the MG and ACx and that auditory driven inhibition dominates the postsynaptic responses in a non-sensory cortical region downstream from the ACx. PMID:26321918

  11. Regional cortical volume and cognitive functioning following traumatic brain injury.

    PubMed

    Spitz, Gershon; Bigler, Erin D; Abildskov, Tracy; Maller, Jerome J; O'Sullivan, Richard; Ponsford, Jennie L

    2013-10-01

    There has been limited examination of the effect of brain pathology on subsequent function. The current study examined the relationships between regional variation in grey matter volume, age and cognitive impairment using a semi-automated image analysis tool. This study included 69 individuals with mild-to-severe TBI, 41 of whom also completed neuropsychological tests of attention, working memory, processing speed, memory and executive functions. A widespread reduction in grey matter volume was associated with increasing age. Regional volumes that were affected also related to the severity of injury, whereby the most severe TBI participants displayed the most significant pathology. Poorer retention of newly learned material was associated with reduced cortical volume in frontal, parietal, and occipital brain regions. In addition, poorer working memory and executive control performance was found for individuals with lower cortical volume in temporal, parietal, and occipital regions. These findings are largely in line with previous literature, which suggests that frontal, temporal, and parietal regions are integral for the encoding of memories into long-term storage, memory retrieval, and working memory. The present study suggests that automated image analysis methods may be used to explore the relationships between regional variation in grey matter volume and cognitive function following TBI. PMID:23872098

  12. Fetal brain regional responses to cerebral hypoperfusion: modulation by estrogen.

    PubMed

    Wood, Charles E; Giroux, Damian; Gridley, Kelly

    2003-12-12

    We have previously demonstrated that cerebral hypoperfusion stimulates several physiological and molecular responses which are components of homeostatic reflexes. Physiological increases in fetal plasma estradiol concentration modulate fetal brain responsiveness to hypotension. In the present study, we tested the effect of cerebral hypoperfusion and/or estradiol on the expression of Fos, the protein product of the gene c-fos in late-gestation fetal sheep. We hypothesized that estrogen and cerebral hypoperfusion alone would augment Fos abundance in various brain regions, including the hypothalamus and brainstem, and that estrogen would augment or otherwise modify the Fos response to cerebral hypoperfusion. Singleton or twin fetuses of time-dated pregnant ewes were chronically catheterized and fitted with an extravascular balloon occluder around the brachiocephalic artery using aseptic techniques. In one-half of the fetuses, we implanted a pellet subcutaneously which released estradiol at a rate of 5 mg in 21 days. Fetuses were studied at least 5 days after surgery (124-128 days' gestation, term is approximately 147 days). One-half of the fetuses were subjected to a 10-min period of brachiocephalic occlusion (BCO). One hour after the start of the experiment, the ewe and fetus were euthanized and the fetal brain was rapidly recovered, dissected, and frozen in a polypropylene tube in an acetone/dry ice bath. Brain tissue was homogenized in a boiling lysis buffer, and protein concentrations measured using the Bradford method. Extracted proteins were electrophoresed on 7.5% polyacrylamide gels, transferred to nitrocellulose membranes, and probed for Fos. In most brain regions, estradiol or BCO altered the expression of Fos. Analyzed by two-way analysis of variance, there was a statistically significant (p<0.05) interaction between estradiol and BCO in brainstem, cerebellum, and hippocampus, nearly significant in hypothalamus (p=0.07) and not statistically significant in

  13. The brain-stem auditory-evoked response in the big brown bat (Eptesicus fuscus) to clicks and frequency-modulated sweeps.

    PubMed

    Burkard, R; Moss, C F

    1994-08-01

    Three experiments were performed to evaluate the effects of stimulus level on the brain-stem auditory-evoked response (BAER) in the big brown bat (Eptesicus fuscus), a species that uses frequency-modulated (FM) sonar sounds for echolocation. In experiment 1, the effects of click level on the BAER were investigated. Clicks were presented at levels of 30 to 90 dB pSPL in 10-dB steps. Each animal responded reliably to clicks at levels of 50 dB pSPL and above, showing a BAER containing four peaks in the first 3-4 ms from click onset (waves i-iv). With increasing click level, BAER peak amplitude increased and peak latency decreased. A decrease in the i-iv interval also occurred with increasing click level. In experiment 2, stimuli were 1-ms linear FM sweeps, decreasing in frequency from 100 to 20 kHz. Stimulus levels ranged from 20 to 90 dB pSPL. BAERs to FM sweeps were observed in all animals for levels of 40 dB pSPL and above. These responses were similar to the click-evoked BAER in waveform morphology, with the notable exception of an additional peak observed at the higher levels of FM sweeps. This peak (wave ia) occurred prior to the first wave seen at lower levels (wave ib). As the level of the FM sweep increased, there was a decrease in peak latency and an increase in peak amplitude. Similarity in the magnitude and behavior of the i-iv and ib-iv intervals suggests that wave ib to FM sweeps is the homolog of the wave i response to click stimuli. Experiment 3 tested the hypothesis that wave ia represented activity emanating from more basal cochlear regions than wave ib. FM sweeps (100-20 kHz) were presented at 90 dB pSPL, and broadband noise was raised in level until the BAER was eliminated. This "masked threshold" occurred at 85 dB SPL of noise. At masked threshold, the broadband noise was steeply high-pass filtered at five cutoff frequencies ranging from 20 to 80 kHz. Generally, wave ia was eliminated for masker cutoff frequencies of 56.6 kHz and below, while wave

  14. Enhanced regional brain metabolic responses to benzodiazepines in cocaine abusers

    SciTech Connect

    Volkow, N.D.; Wang, G.J.; Fowler, J.S.

    1997-05-01

    While dopamine (DA) appears to be crucial for cocaine reinforcement, its involvement in cocaine addiction is much less clear. Using PET we have shown persistent reductions in striatal DA D2 receptors (which arc predominantly located on GABA cells) in cocaine abusers. This finding coupled to GABA`s role as an effector for DA led us to investigate if there were GABAergic abnormalities in cocaine abusers. In this study we measured regional brain metabolic responses to lorazepam, to indirectly assess GABA function (benzodiazepines facilitate GABAergic neurotransmission). Methods: The experimental subjects consisted of 12 active cocaine abusers and 32 age matched controls. Each subject underwent two PET FDG scans obtained within 1 week of each other. The first FDG scan was obtained after administration of placebo (3 cc of saline solution) given 40-50 minutes prior to FDG; and the second after administration of lorazepam (30 {mu}g/kg) given 40-50 minutes prior to FDG. The subjects were blind to the drugs received. Results: Lorazepam-induced sleepiness was significantly greater in abusers than in controls (p<0.001). Lorazepam-induced decreases in brain glucose metabolism were significantly larger in cocaine abusers than in controls. Whereas in controls whole brain metabolism decreased 13{+-}7 %, in cocaine abusers it decreased 21{+-}13 % (p < 0.05). Lorazepam-induced decrements in regional metabolism were significantly larger in striatum (p < 0.0 1), thalamus (p < 0.01) and cerebellum (p < 0.005) of cocaine abusers than of controls (ANOVA diagnosis by condition (placebo versus lorazepam) interaction effect). The only brain region for which the absolute metabolic changes-induced by lorazepam in cocaine abusers were equivalent to those in controls was the orbitofrontal cortex. These results document an accentuated sensitivity to benzodiazepines in cocaine abusers which is compatible with disrupted GABAergic function in these patients.

  15. Repetitive Transcranial Magnetic Stimulation Activates Specific Regions in Rat Brain

    NASA Astrophysics Data System (ADS)

    Ji, Ru-Rong; Schlaepfer, Thomas E.; Aizenman, Carlos D.; Epstein, Charles M.; Qiu, Dike; Huang, Justin C.; Rupp, Fabio

    1998-12-01

    Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive technique to induce electric currents in the brain. Although rTMS is being evaluated as a possible alternative to electroconvulsive therapy for the treatment of refractory depression, little is known about the pattern of activation induced in the brain by rTMS. We have compared immediate early gene expression in rat brain after rTMS and electroconvulsive stimulation, a well-established animal model for electroconvulsive therapy. Our result shows that rTMS applied in conditions effective in animal models of depression induces different patterns of immediate-early gene expression than does electroconvulsive stimulation. In particular, rTMS evokes strong neural responses in the paraventricular nucleus of the thalamus (PVT) and in other regions involved in the regulation of circadian rhythms. The response in PVT is independent of the orientation of the stimulation probe relative to the head. Part of this response is likely because of direct activation, as repetitive magnetic stimulation also activates PVT neurons in brain slices.

  16. Information processing becomes slower and predominantly serial in aging: Characterization of response-related brain potentials in an auditory-visual distraction-attention task.

    PubMed

    Cid-Fernández, Susana; Lindín, Mónica; Díaz, Fernando

    2016-01-01

    The aim of this study was to evaluate the effects of aging and attentional capture provoked by novel auditory stimuli on behavior (reaction time [RT], hits) and on response-related brain potentials (preRFP, CRN, postRFP, parietalRP) to target visual stimuli. Twenty-two young, 27 middle-aged, and 24 old adults performed an auditory-visual distraction-attention task. The RTs and latencies of preRFP, postRFP and parietalRT were longer in old and middle-aged than in young participants, reflecting the well-established age-related slowing of processing and performance. The inter-peak latencies (P3b-preRFP, preRFP-parietalRP, parietalRP-postRFP) were also longer in old and middle-aged than in young participants, further indicating an age-related tendency to increased predominance of serial (rather than parallel) processing of information, and that preRFP, CRN, postRFP, and parietalRP represent different cognitive processes from those indexed by the stimulus-related P3b. Finally, a distraction effect in performance (all three groups) and in postRFP latency (only middle-aged group) was also observed. PMID:26589359

  17. Region based Brain Computer Interface for a home control application.

    PubMed

    Akman Aydin, Eda; Bay, Omer Faruk; Guler, Inan

    2015-08-01

    Environment control is one of the important challenges for disabled people who suffer from neuromuscular diseases. Brain Computer Interface (BCI) provides a communication channel between the human brain and the environment without requiring any muscular activation. The most important expectation for a home control application is high accuracy and reliable control. Region-based paradigm is a stimulus paradigm based on oddball principle and requires selection of a target at two levels. This paper presents an application of region based paradigm for a smart home control application for people with neuromuscular diseases. In this study, a region based stimulus interface containing 49 commands was designed. Five non-disabled subjects were attended to the experiments. Offline analysis results of the experiments yielded 95% accuracy for five flashes. This result showed that region based paradigm can be used to select commands of a smart home control application with high accuracy in the low number of repetitions successfully. Furthermore, a statistically significant difference was not observed between the level accuracies. PMID:26736451

  18. Radioreceptor assay of opioid peptides in selected canine brain regions

    SciTech Connect

    Desiderio, D.M.; Takeshita, H.

    1985-09-01

    A radioreceptor assay using the opioid delta receptor-preferring ligand D-/sup 2/ala, D-/sup 5/leu leucine enkephalin (/sup 3/H-DADL) and the broader-specificity ligand /sup 3/H-etorphine was used to measure five HPLC-purified neuropeptide fractions derived from the peptide-rich fraction of tissue homogenates of nine anatomical regions of the canine brain. The receptoractive peptides studied were methionine enkephalin, alpha-neo-endorphin, dynorphin 1-8, methionine enkephalin-Arg-Phe, and leucine enkephalin. These peptides derive from two larger precursors: proenkephalin A, which contains methionine enkephalin, leucine enkephalin, methionine enkephalin-Arg-Phe; and proenkephalin B, which contains alpha-neo-endorphin and dynorphin 1-8. Receptoractive peptides were measured in the peptide-rich fraction derived from homogenates of canine hypothalamus, pituitary, caudate nucleus, amygdala, hippocampus, mid-brain, thalamus, pons-medulla, and cortex.

  19. Multimodal lexical processing in auditory cortex is literacy skill dependent.

    PubMed

    McNorgan, Chris; Awati, Neha; Desroches, Amy S; Booth, James R

    2014-09-01

    Literacy is a uniquely human cross-modal cognitive process wherein visual orthographic representations become associated with auditory phonological representations through experience. Developmental studies provide insight into how experience-dependent changes in brain organization influence phonological processing as a function of literacy. Previous investigations show a synchrony-dependent influence of letter presentation on individual phoneme processing in superior temporal sulcus; others demonstrate recruitment of primary and associative auditory cortex during cross-modal processing. We sought to determine whether brain regions supporting phonological processing of larger lexical units (monosyllabic words) over larger time windows is sensitive to cross-modal information, and whether such effects are literacy dependent. Twenty-two children (age 8-14 years) made rhyming judgments for sequentially presented word and pseudoword pairs presented either unimodally (auditory- or visual-only) or cross-modally (audiovisual). Regression analyses examined the relationship between literacy and congruency effects (overlapping orthography and phonology vs. overlapping phonology-only). We extend previous findings by showing that higher literacy is correlated with greater congruency effects in auditory cortex (i.e., planum temporale) only for cross-modal processing. These skill effects were specific to known words and occurred over a large time window, suggesting that multimodal integration in posterior auditory cortex is critical for fluent reading. PMID:23588185

  20. The Drosophila Auditory System

    PubMed Central

    Boekhoff-Falk, Grace; Eberl, Daniel F.

    2013-01-01

    Development of a functional auditory system in Drosophila requires specification and differentiation of the chordotonal sensilla of Johnston’s organ (JO) in the antenna, correct axonal targeting to the antennal mechanosensory and motor center (AMMC) in the brain, and synaptic connections to neurons in the downstream circuit. Chordotonal development in JO is functionally complicated by structural, molecular and functional diversity that is not yet fully understood, and construction of the auditory neural circuitry is only beginning to unfold. Here we describe our current understanding of developmental and molecular mechanisms that generate the exquisite functions of the Drosophila auditory system, emphasizing recent progress and highlighting important new questions arising from research on this remarkable sensory system. PMID:24719289

  1. Brain Regions Associated With Internalizing and Externalizing Psychiatric Symptoms in Patients With Penetrating Traumatic Brain Injury.

    PubMed

    Huey, Edward D; Lee, Seonjoo; Lieberman, Jeffrey A; Devanand, D P; Brickman, Adam M; Raymont, Vanessa; Krueger, Frank; Grafman, Jordan

    2016-01-01

    A factor structure underlying DSM-IV diagnoses has been previously reported in neurologically intact patients. The authors determined the brain regions associated with factors underlying DSM-IV diagnoses and compared the ability of DSM-IV diagnoses, factor scores, and self-report measures to account for the neuroanatomical findings in patients with penetrating brain injuries. This prospective cohort study included 254 Vietnam War veterans: 199 with penetrating brain injuries and 55 matched control participants. Measures include DSM-IV diagnoses (from a Structured Clinical Interview for DSM), self-report measures of depression and anxiety, and CT scans. Factors underlying DSM-IV diagnoses were determined using an exploratory factor analysis and correlated with percent of brain regions affected. The ability of the factor scores, DSM-IV diagnoses, and the self-report psychiatric measures to account for the anatomical variance was compared with multiple regressions. Internalizing and externalizing factors were identified in these brain-injured patients. Damage to the left amygdala and bilateral basal ganglia was associated with lower internalizing factor scores, and damage to the left medial orbitofrontal cortex (OFC) with higher, and bilateral hippocampi with lower, externalizing factor scores. Factor scores best predicted left amygdala and bilateral hippocampal involvement, whereas DSM-IV diagnoses best predicted bilateral basal ganglia and left OFC involvement. Damage to the limbic areas involved in the processing of emotional and reward information, including structures involved in the National Institute of Mental Health's Research Domain Criteria Negative Valence Domain, influences the development of internalizing and externalizing psychiatric symptoms. Self-report measures underperformed DSM-IV and factor scores in predicting neuroanatomical findings. PMID:26715034

  2. Regional brain metabolism in a murine systemic lupus erythematosus model.

    PubMed

    Vo, An; Volpe, Bruce T; Tang, Chris C; Schiffer, Wynne K; Kowal, Czeslawa; Huerta, Patricio T; Uluğ, Aziz M; Dewey, Stephen L; Eidelberg, David; Diamond, Betty

    2014-08-01

    Systemic lupus erythematosus (SLE) is characterized by multiorgan inflammation, neuropsychiatric disorders (NPSLE), and anti-nuclear antibodies. We previously identified a subset of anti-DNA antibodies (DNRAb) cross-reactive with the N-methyl-D-aspartate receptor, present in 30% to 40% of patients, able to enhance excitatory post-synaptic potentials and trigger neuronal apoptosis. DNRAb+ mice exhibit memory impairment or altered fear response, depending on whether the antibody penetrates the hippocampus or amygdala. Here, we used 18F-fluorodeoxyglucose (FDG) microPET to plot changes in brain metabolism after regional blood-brain barrier (BBB) breach. In DNRAb+ mice, metabolism declined at the site of BBB breach in the first 2 weeks and increased over the next 2 weeks. In contrast, DNRAb- mice exhibited metabolic increases in these regions over the 4 weeks after the insult. Memory impairment was present in DNRAb+ animals with hippocampal BBB breach and altered fear conditioning in DNRAb+ mice with amygdala BBB breach. In DNRAb+ mice, we observed an inverse relationship between neuron number and regional metabolism, while a positive correlation was observed in DNRAb- mice. These findings suggest that local metabolic alterations in this model take place through different mechanisms with distinct time courses, with important implications for the interpretation of imaging data in SLE subjects. PMID:24824914

  3. Site of auditory plasticity in the brain stem (VLVp) of the owl revealed by early monaural occlusion.

    PubMed

    Mogdans, J; Knudsen, E I

    1994-12-01

    1. The optic tectum of the barn owl contains a physiological map of interaural level difference (ILD) that underlies, in part, its map of auditory space. Monaural occlusion shifts the range of ILDs experienced by an animal and alters the correspondence of ILDs with source locations. Chronic monaural occlusion during development induces an adaptive shift in the tectal ILD map that compensates for the effects of the earplug. The data presented in this study indicate that one site of plasticity underlying this adaptive adjustment is in the posterior division of the ventral nucleus of the lateral lemniscus (VLVp), the first site of ILD comparison in the auditory pathway. 2. Single and multiple unit sites were recorded in the optic tecta and VLVps of ketamine-anesthetized owls. The owls were raised from 4 wk of age with one ear occluded with an earplug. Auditory testing, using digitally synthesized dichotic stimuli, was carried out 8-16 wk later with the earplug removed. The adaptive adjustment in ILD coding in each bird was quantified as the shift from normal ILD tuning measured in the optic tectum. Evidence of adaptive adjustment in the VLVp was based on statistical differences between the VLVp's ipsilateral and contralateral to the occluded ear in the sensitivity of units to excitatory-ear and inhibitory-ear stimulation. 3. The balance of excitatory to inhibitory influences on VLVp units was shifted in the adaptive direction in six out of eight owls. In three of these owls, adaptive differences in inhibition, but not in excitation, were found. For this group of owls, the patterns of response properties across the two VLVps can only be accounted for by plasticity in the VLVp. For the other three owls, the possibility that the difference between the two VLVps resulted from damage to one of the VLVps could not be eliminated, and for one of these, plasticity at a more peripheral site (in the cochlea or cochlear nucleus) could also explain the data. In the remaining two

  4. Face processing in autism spectrum disorders: From brain regions to brain networks.

    PubMed

    Nomi, Jason S; Uddin, Lucina Q

    2015-05-01

    Autism spectrum disorder (ASD) is characterized by reduced attention to social stimuli including the human face. This hypo-responsiveness to stimuli that are engaging to typically developing individuals may result from dysfunctioning motivation, reward, and attention systems in the brain. Here we review an emerging neuroimaging literature that emphasizes a shift from focusing on hypo-activation of isolated brain regions such as the fusiform gyrus, amygdala, and superior temporal sulcus in ASD to a more holistic approach to understanding face perception as a process supported by distributed cortical and subcortical brain networks. We summarize evidence for atypical activation patterns within brain networks that may contribute to social deficits characteristic of the disorder. We conclude by pointing to gaps in the literature and future directions that will continue to shed light on aspects of face processing in autism that are still under-examined. In particular, we highlight the need for more developmental studies and studies examining ecologically valid and naturalistic social stimuli. PMID:25829246

  5. Face processing in autism spectrum disorders: from brain regions to brain networks

    PubMed Central

    Nomi, Jason S.; Uddin, Lucina Q.

    2015-01-01

    Autism spectrum disorder (ASD) is characterized by reduced attention to social stimuli including the human face. This hypo-responsiveness to stimuli that are engaging to typically developing individuals may result from dysfunctioning motivation, reward, and attention systems in the brain. Here we review an emerging neuroimaging literature that emphasizes a shift from focusing on hypo-activation of isolated brain regions such as the fusiform gyrus, amygdala, and superior temporal sulcus in ASD to a more holistic approach to understanding face perception as a process supported by distributed cortical and subcortical brain networks. We summarize evidence for atypical activation patterns within brain networks that may contribute to social deficits characteristic of the disorder. We conclude by pointing to gaps in the literature and future directions that will continue to shed light on aspects of face processing in autism that are still under-examined. In particular, we highlight the need for more developmental studies and studies examining ecologically valid and naturalistic social stimuli. PMID:25829246

  6. Sex, acceleration, brain imaging, and rhesus monkeys: Converging evidence for an evolutionary bias for looming auditory motion

    NASA Astrophysics Data System (ADS)

    Neuhoff, John G.

    2003-04-01

    Increasing acoustic intensity is a primary cue to looming auditory motion. Perceptual overestimation of increasing intensity could provide an evolutionary selective advantage by specifying that an approaching sound source is closer than actual, thus affording advanced warning and more time than expected to prepare for the arrival of the source. Here, multiple lines of converging evidence for this evolutionary hypothesis are presented. First, it is shown that intensity change specifying accelerating source approach changes in loudness more than equivalent intensity change specifying decelerating source approach. Second, consistent with evolutionary hunter-gatherer theories of sex-specific spatial abilities, it is shown that females have a significantly larger bias for rising intensity than males. Third, using functional magnetic resonance imaging in conjunction with approaching and receding auditory motion, it is shown that approaching sources preferentially activate a specific neural network responsible for attention allocation, motor planning, and translating perception into action. Finally, it is shown that rhesus monkeys also exhibit a rising intensity bias by orienting longer to looming tones than to receding tones. Together these results illustrate an adaptive perceptual bias that has evolved because it provides a selective advantage in processing looming acoustic sources. [Work supported by NSF and CDC.

  7. Experience-dependent modulation of tonotopic neural responses in human auditory cortex.

    PubMed Central

    Morris, J S; Friston, K J; Dolan, R J

    1998-01-01

    Experience-dependent plasticity of receptive fields in the auditory cortex has been demonstrated by electrophysiological experiments in animals. In the present study we used PET neuroimaging to measure regional brain activity in volunteer human subjects during discriminatory classical conditioning of high (8000 Hz) or low (200 Hz) frequency tones by an aversive 100 dB white noise burst. Conditioning-related, frequency-specific modulation of tonotopic neural responses in the auditory cortex was observed. The modulated regions of the auditory cortex positively covaried with activity in the amygdala, basal forebrain and orbitofrontal cortex, and showed context-specific functional interactions with the medial geniculate nucleus. These results accord with animal single-unit data and support neurobiological models of auditory conditioning and value-dependent neural selection. PMID:9608726

  8. Steady state visually evoked potential correlates of auditory hallucinations in schizophrenia.

    PubMed

    Line, P; Silberstein, R B; Wright, J J; Copolov, D L

    1998-11-01

    This study attempted to localize regions of brain electrical activity associated with the onset of auditory hallucinations. Changes in Steady State Visually Evoked Potential (SSVEP) topography associated with the onset of spontaneous auditory hallucinations was studied in eight schizophrenic patients. The SSVEP elicited by a spatially uniform sinusoidally varying visual flicker was recorded using a 64-channel electrode helmet. A large and significant decrease in SSVEP latency in the right temporo/parietal region occurred in the second prior to the report of auditory hallucinations. A control task with matching motor movements produced no significant decrease in SSVEP latency in the same right temporo/parietal location. This finding suggests that activity of fine temporal resolution in the neural networks in the right temporo/parietal area may be implicated in the genesis of auditory hallucination, in conformity with certain neuropsychological theories. PMID:9811555

  9. The shape of ears to come: dynamic coding of auditory space.

    PubMed

    King, A J.; Schnupp, J W.H.; Doubell, T P.

    2001-06-01

    In order to pinpoint the location of a sound source, we make use of a variety of spatial cues that arise from the direction-dependent manner in which sounds interact with the head, torso and external ears. Accurate sound localization relies on the neural discrimination of tiny differences in the values of these cues and requires that the brain circuits involved be calibrated to the cues experienced by each individual. There is growing evidence that the capacity for recalibrating auditory localization continues well into adult life. Many details of how the brain represents auditory space and of how those representations are shaped by learning and experience remain elusive. However, it is becoming increasingly clear that the task of processing auditory spatial information is distributed over different regions of the brain, some working hierarchically, others independently and in parallel, and each apparently using different strategies for encoding sound source location. PMID:11390297

  10. Microglial brain region-dependent diversity and selective regional sensitivities to ageing

    PubMed Central

    Grabert, Kathleen; Michoel, Tom; Karavolos, Michail H; Clohisey, Sara; Baillie, J Kenneth; Stevens, Mark P; Freeman, Tom C; Summers, Kim M; McColl, Barry W

    2015-01-01

    Microglia play critical roles in neural development, homeostasis and neuroinflammation and are increasingly implicated in age-related neurological dysfunction. Neurodegeneration often occurs in disease-specific spatially-restricted patterns, the origins of which are unknown. We performed the first genome-wide analysis of microglia from discrete brain regions across the adult lifespan of the mouse and reveal that microglia have distinct region-dependent transcriptional identities and age in a regionally variable manner. In the young adult brain, differences in bioenergetic and immunoregulatory pathways were the major sources of heterogeneity and suggested that cerebellar and hippocampal microglia exist in a more immune vigilant state. Immune function correlated with regional transcriptional patterns. Augmentation of the distinct cerebellar immunophenotype and a contrasting loss in distinction of the hippocampal phenotype among forebrain regions were key features during ageing. Microglial diversity may enable regionally localised homeostatic functions but could also underlie region-specific sensitivities to microglial dysregulation and involvement in age-related neurodegeneration. PMID:26780511

  11. Microglial brain region-dependent diversity and selective regional sensitivities to aging.

    PubMed

    Grabert, Kathleen; Michoel, Tom; Karavolos, Michail H; Clohisey, Sara; Baillie, J Kenneth; Stevens, Mark P; Freeman, Tom C; Summers, Kim M; McColl, Barry W

    2016-03-01

    Microglia have critical roles in neural development, homeostasis and neuroinflammation and are increasingly implicated in age-related neurological dysfunction. Neurodegeneration often occurs in disease-specific, spatially restricted patterns, the origins of which are unknown. We performed to our knowledge the first genome-wide analysis of microglia from discrete brain regions across the adult lifespan of the mouse, and found that microglia have distinct region-dependent transcriptional identities and age in a regionally variable manner. In the young adult brain, differences in bioenergetic and immunoregulatory pathways were the major sources of heterogeneity and suggested that cerebellar and hippocampal microglia exist in a more immune-vigilant state. Immune function correlated with regional transcriptional patterns. Augmentation of the distinct cerebellar immunophenotype and a contrasting loss in distinction of the hippocampal phenotype among forebrain regions were key features during aging. Microglial diversity may enable regionally localized homeostatic functions but could also underlie region-specific sensitivities to microglial dysregulation and involvement in age-related neurodegeneration. PMID:26780511

  12. Positron Emission Tomography Imaging Reveals Auditory and Frontal Cortical Regions Involved with Speech Perception and Loudness Adaptation.

    PubMed

    Berding, Georg; Wilke, Florian; Rode, Thilo; Haense, Cathleen; Joseph, Gert; Meyer, Geerd J; Mamach, Martin; Lenarz, Minoo; Geworski, Lilli; Bengel, Frank M; Lenarz, Thomas; Lim, Hubert H

    2015-01-01

    Considerable progress has been made in the treatment of hearing loss with auditory implants. However, there are still many implanted patients that experience hearing deficiencies, such as limited speech understanding or vanishing perception with continuous stimulation (i.e., abnormal loudness adaptation). The present study aims to identify specific patterns of cerebral cortex activity involved with such deficiencies. We performed O-15-water positron emission tomography (PET) in patients implanted with electrodes within the cochlea, brainstem, or midbrain to investigate the pattern of cortical activation in response to speech or continuous multi-tone stimuli directly inputted into the implant processor that then delivered electrical patterns through those electrodes. Statistical parametric mapping was performed on a single subject basis. Better speech understanding was correlated with a larger extent of bilateral auditory cortex activation. In contrast to speech, the continuous multi-tone stimulus elicited mainly unilateral auditory cortical activity in which greater loudness adaptation corresponded to weaker activation and even deactivation. Interestingly, greater loudness adaptation was correlated with stronger activity within the ventral prefrontal cortex, which could be up-regulated to suppress the irrelevant or aberrant signals into the auditory cortex. The ability to detect these specific cortical patterns and differences across patients and stimuli demonstrates the potential for using PET to diagnose auditory function or dysfunction in implant patients, which in turn could guide the development of appropriate stimulation strategies for improving hearing rehabilitation. Beyond hearing restoration, our study also reveals a potential role of the frontal cortex in suppressing irrelevant or aberrant activity within the auditory cortex, and thus may be relevant for understanding and treating tinnitus. PMID:26046763

  13. Recovery from auditory and visual neglect after optokinetic stimulation with pursuit eye movements--transient modulation and enduring treatment effects.

    PubMed

    Kerkhoff, G; Keller, I; Artinger, F; Hildebrandt, H; Marquardt, C; Reinhart, S; Ziegler, W

    2012-05-01

    Optokinetic stimulation (OKS) modulates many facets of the neglect syndrome. This sensory stimulation technique is known to activate multiple brain regions (temporo-parietal cortex, basal ganglia, brain stem, cerebellum) some of which are involved in auditory and visual space coding. Here, we evaluated whether OKS modulates auditory neglect transiently and induces a sustained effect (Study 1), and whether repetitive OKS permanently recovers auditory neglect (Study 2). In Study 1, 20 patients with visuospatial neglect and auditory neglect in an auditory midline task following rightsided stroke were randomly allocated to an experimental and a control group matched for neglect severity and socio-demographic factors. Both groups showed a stable, pathological shift of their auditory subjective median plane (ASMP) in front space to the right side. During leftward OKS the experimental group showed a complete normalization of the shift of the ASMP, which endured until 30 min poststimulation, and returned almost to baseline values 24h after OKS. In contrast, the control group who viewed the identical but static dot pattern, showed neither change in their ASMP during this condition, nor any significant change at 30 min or 24h poststimulation. In Study 2, we show in two samples of neglect patients (N = 3 each) that repetitive leftward OKS with smooth pursuit eye movements as a therapy induces lasting improvements in auditory (the ASMP) and visual neglect while visual scanning therapy yielded no measurable effects on auditory and significantly smaller effects on visual neglect. In conclusion, the experiments show that a single session of OKS induces rapid though transient recovery from auditory neglect including a sustained effect after termination of stimulation, while repetitive OKS therapy yields enduring and multimodal recovery from auditory and visual neglect. OKS therapy with pursuit eye movements therefore represents a multimodally effective and easily applicable

  14. Effect Of Electromagnetic Waves Emitted From Mobile Phone On Brain Stem Auditory Evoked Potential In Adult Males.

    PubMed

    Singh, K

    2015-01-01

    Mobile phone (MP) is commonly used communication tool. Electromagnetic waves (EMWs) emitted from MP may have potential health hazards. So, it was planned to study the effect of electromagnetic waves (EMWs) emitted from the mobile phone on brainstem auditory evoked potential (BAEP) in male subjects in the age group of 20-40 years. BAEPs were recorded using standard method of 10-20 system of electrode placement and sound click stimuli of specified intensity, duration and frequency.Right ear was exposed to EMW emitted from MP for about 10 min. On comparison of before and after exposure to MP in right ear (found to be dominating ear), there was significant increase in latency of II, III (p < 0.05) and V (p < 0.001) wave, amplitude of I-Ia wave (p < 0.05) and decrease in IPL of III-V wave (P < 0.05) after exposure to MP. But no significant change was found in waves of BAEP in left ear before vs after MP. On comparison of right (having exposure routinely as found to be dominating ear) and left ears (not exposed to MP), before exposure to MP, IPL of IIl-V wave and amplitude of V-Va is more (< 0.001) in right ear compared to more latency of III and IV wave (< 0.001) in left ear. After exposure to MP, the amplitude of V-Va was (p < 0.05) more in right ear compared to left ear. In conclusion, EMWs emitted from MP affects the auditory potential. PMID:27530007

  15. Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy

    PubMed Central

    Lecaignard, Françoise; Bertrand, Olivier; Gimenez, Gérard; Mattout, Jérémie; Caclin, Anne

    2015-01-01

    Deviant stimuli, violating regularities in a sensory environment, elicit the mismatch negativity (MMN), largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience) are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities. PMID:26441602

  16. Implicit learning of predictable sound sequences modulates human brain responses at different levels of the auditory hierarchy.

    PubMed

    Lecaignard, Françoise; Bertrand, Olivier; Gimenez, Gérard; Mattout, Jérémie; Caclin, Anne

    2015-01-01

    Deviant stimuli, violating regularities in a sensory environment, elicit the mismatch negativity (MMN), largely described in the Event-Related Potential literature. While it is widely accepted that the MMN reflects more than basic change detection, a comprehensive description of mental processes modulating this response is still lacking. Within the framework of predictive coding, deviance processing is part of an inference process where prediction errors (the mismatch between incoming sensations and predictions established through experience) are minimized. In this view, the MMN is a measure of prediction error, which yields specific expectations regarding its modulations by various experimental factors. In particular, it predicts that the MMN should decrease as the occurrence of a deviance becomes more predictable. We conducted a passive oddball EEG study and manipulated the predictability of sound sequences by means of different temporal structures. Importantly, our design allows comparing mismatch responses elicited by predictable and unpredictable violations of a simple repetition rule and therefore departs from previous studies that investigate violations of different time-scale regularities. We observed a decrease of the MMN with predictability and interestingly, a similar effect at earlier latencies, within 70 ms after deviance onset. Following these pre-attentive responses, a reduced P3a was measured in the case of predictable deviants. We conclude that early and late deviance responses reflect prediction errors, triggering belief updating within the auditory hierarchy. Beside, in this passive study, such perceptual inference appears to be modulated by higher-level implicit learning of sequence statistical structures. Our findings argue for a hierarchical model of auditory processing where predictive coding enables implicit extraction of environmental regularities. PMID:26441602

  17. Brain Region-Specific Trafficking of the Dopamine Transporter

    PubMed Central

    Block, Ethan R.; Nuttle, Jacob; Balcita-Pedicino, Judith Joyce; Caltagarone, John; Watkins, Simon C.

    2015-01-01

    The dopamine (DA) transporter (DAT) controls dopaminergic neurotransmission by removing extracellular DA. Although DA reuptake is proposed to be regulated by DAT traffic to and from the cell surface, the membrane trafficking system involved in the endocytic cycling of DAT in the intact mammalian brain has not been characterized. Hence, we performed immunolabeling and quantitative analysis of the subcellular and regional distribution of DAT using the transgenic knock-in mouse expressing hemagglutinin (HA) epitope-tagged DAT (HA-DAT) and by using a combination of electron microscopy and a novel method for immunofluorescence labeling of HA-DAT in acute sagittal brain slices. Both approaches demonstrated that, in midbrain somatodendritic regions, HA-DAT was present in the plasma membrane, endoplasmic reticulum, and Golgi complex, with a small fraction in early and recycling endosomes and an even smaller fraction in late endosomes and lysosomes. In the striatum and in axonal tracts between the midbrain and striatum, HA-DAT was detected predominantly in the plasma membrane, and quantitative analysis revealed increased DAT density in striatal compared with midbrain plasma membranes. Endosomes were strikingly rare and lysosomes were absent in striatal axons, in which there was little intracellular HA-DAT. Acute administration of amphetamine in vivo (60 min) or to slices ex vivo (10–60 min) did not result in detectable changes in DAT distribution. Altogether, these data provide evidence for regional differences in DAT plasma membrane targeting and retention and suggest a surprisingly low level of endocytic trafficking of DAT in the striatum along with limited DAT endocytic activity in somatodendritic areas. SIGNIFICANCE STATEMENT The dopamine transporter (DAT) is the key regulator of the dopamine neurotransmission in the CNS. In the present study, we developed a new approach for studying DAT localization and dynamics in intact neurons in acute sagittal brain slices from

  18. Diminished Auditory Responses during NREM Sleep Correlate with the Hierarchy of Language Processing

    PubMed Central

    Furman-Haran, Edna; Arzi, Anat; Levkovitz, Yechiel; Malach, Rafael

    2016-01-01

    Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI) during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM) sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG) cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations. PMID:27310812

  19. Diminished Auditory Responses during NREM Sleep Correlate with the Hierarchy of Language Processing.

    PubMed

    Wilf, Meytal; Ramot, Michal; Furman-Haran, Edna; Arzi, Anat; Levkovitz, Yechiel; Malach, Rafael

    2016-01-01

    Natural sleep provides a powerful model system for studying the neuronal correlates of awareness and state changes in the human brain. To quantitatively map the nature of sleep-induced modulations in sensory responses we presented participants with auditory stimuli possessing different levels of linguistic complexity. Ten participants were scanned using functional magnetic resonance imaging (fMRI) during the waking state and after falling asleep. Sleep staging was based on heart rate measures validated independently on 20 participants using concurrent EEG and heart rate measurements and the results were confirmed using permutation analysis. Participants were exposed to three types of auditory stimuli: scrambled sounds, meaningless word sentences and comprehensible sentences. During non-rapid eye movement (NREM) sleep, we found diminishing brain activation along the hierarchy of language processing, more pronounced in higher processing regions. Specifically, the auditory thalamus showed similar activation levels during sleep and waking states, primary auditory cortex remained activated but showed a significant reduction in auditory responses during sleep, and the high order language-related representation in inferior frontal gyrus (IFG) cortex showed a complete abolishment of responses during NREM sleep. In addition to an overall activation decrease in language processing regions in superior temporal gyrus and IFG, those areas manifested a loss of semantic selectivity during NREM sleep. Our results suggest that the decreased awareness to linguistic auditory stimuli during NREM sleep is linked to diminished activity in high order processing stations. PMID:27310812

  20. Preferred EEG brain states at stimulus onset in a fixed interstimulus interval equiprobable auditory Go/NoGo task: a definitive study.

    PubMed

    Barry, Robert J; De Blasio, Frances M; De Pascalis, Vilfredo; Karamacoska, Diana

    2014-10-01

    This study examined the occurrence of preferred EEG phase states at stimulus onset in an equiprobable auditory Go/NoGo task with a fixed interstimulus interval, and their effects on the resultant event-related potentials (ERPs). We used a sliding short-time FFT decomposition of the EEG at Cz for each trial to assess prestimulus EEG activity in the delta, theta, alpha and beta bands. We determined the phase of each 2 Hz narrow-band contributing to these four broad bands at 125 ms before each stimulus onset, and for the first time, avoided contamination from poststimulus EEG activity. This phase value was extrapolated 125 ms to obtain the phase at stimulus onset, combined into the broad-band phase, and used to sort trials into four phase groups for each of the four broad bands. For each band, ERPs were derived for each phase from the raw EEG activity at 19 sites. Data sets from each band were separately decomposed using temporal Principal Components Analyses with unrestricted VARIMAX rotation to extract N1-1, PN, P2, P3, SW and LP components. Each component was analysed as a function of EEG phase at stimulus onset in the context of a simple conceptualisation of orthogonal phase effects (cortical negativity vs. positivity, negative driving vs. positive driving, waxing vs. waning). The predicted non-random occurrence of phase-defined brain states was confirmed. The preferred states of negativity, negative driving, and waxing were each associated with more efficient stimulus processing, as reflected in amplitude differences of the components. The present results confirm the existence of preferred brain states and their impact on the efficiency of brain dynamics in perceptual and cognitive processing. PMID:25043955

  1. Brain metabolite concentrations across cortical regions in healthy adults

    PubMed Central

    Bracken, Bethany K.; Jensen, J. Eric; Prescot, Andrew P.; Cohen, Bruce M.; Renshaw, Perry F.; Öngür, Dost

    2010-01-01

    Magnetic resonance spectroscopy (MRS) can provide in vivo information about metabolite levels across multiple brain regions. This study used MRS to examine concentrations of N-acetylaspartate (NAA), a marker of neuronal integrity and function, and choline (Cho) which is related to the amount of cell membrane per unit volume, in anterior cingulate cortex (ACC) and parieto-occipital cortex (POC) in healthy individuals. Data were drawn from two experiments which examined glutamatergic and GABAergic signaling in schizophrenia and bipolar disorder. After controlling for gray matter percentages, NAA/Creatine (Cr) was 18% higher in POC than in ACC (p<0.001); Cho/Cr was 46% lower in POC than in ACC (p<0.001). There was an effect of study (p<0.001 for both metabolites), but no region by study interaction (NAA p=0.101, Cho p=0.850). Since NAA is localized to the intracellular space, these data suggest that ACC neuronal compartment is reduced as compared with POC, or that there is a lower concentration of NAA per cell in the ACC than POC, or both. Since elevated Cho suggests more cell membrane per unit volume, reduced NAA in ACC appears to be coupled with increases in overall cell membrane compartment. These findings are consistent with a number of previous studies using proton MRS which found increasing NAA and decreasing Cho moving caudally, and with post mortem anatomical studies which found neurons in more widely spaced bundles in ACC when compared to parietal and occipital cortices. MRS may be a useful tool for studying physical properties of the living human brain. PMID:21081116

  2. Gender and environmental effects on regional brain-derived neurotrophic factor expression after experimental traumatic brain injury.

    PubMed

    Chen, X; Li, Y; Kline, A E; Dixon, C E; Zafonte, R D; Wagner, A K

    2005-01-01

    Alterations in brain-derived neurotrophic factor expression have been reported in multiple brain regions acutely after traumatic brain injury, however neither injury nor post-injury environmental enrichment has been shown to affect hippocampal brain-derived neurotrophic factor gene expression in male rats chronically post-injury. Studies have demonstrated hormone-related neuroprotection for female rats after traumatic brain injury, and estrogen and exercise both influence brain-derived neurotrophic factor levels. Despite recent studies suggesting that exposure post-traumatic brain injury to environmental enrichment improves cognitive recovery in male rats, we have shown that environmental enrichment mediated improvements with spatial learning are gender specific and only positively affect males. Therefore the purpose of this study was to evaluate the effect of gender and environmental enrichment on chronic post-injury cortical and hippocampal brain-derived neurotrophic factor protein expression. Sprague-Dawley male and cycling female rats were placed into environmental enrichment or standard housing after controlled cortical impact or sham surgery. Four weeks post-surgery, hippocampal and frontal cortex brain-derived neurotrophic factor expression were examined using Western blot. Results revealed significant increases in brain-derived neurotrophic factor expression in the frontal cortex ipsilateral to injury for males (P=0.03). Environmental enrichment did not augment this effect. Neither environmental enrichment nor injury significantly affected cortical brain-derived neurotrophic factor expression for females. In the hippocampus ipsilateral to injury brain-derived neurotrophic factor expression for both males and females was half (49% and 51% respectively) of that observed in shams housed in the standard environment. For injured males, there was a trend in this region for environmental enrichment to restore brain-derived neurotrophic factor levels to sham values

  3. Effect of oxotremorine on the acetylcholine content of whole brain and various brain regions in the pigeon

    PubMed Central

    Igić, R.

    1971-01-01

    Oxotremorine (0·125 mg/kg) produces a significant increase in total acetylcholine content in whole pigeon brain. The contribution of different regions to this increase varies. The largest increase occurs in the nucleus basalis (paleostriatum augmentatum), a region which is highly involved in motor control. The mechanism by which oxotremorine increases the acetylcholine content of brain and the causal relationship between the rise in acetylcholine content and tremor are discussed. PMID:5091163

  4. Modulation of auditory processing during speech movement planning is limited in adults who stutter.

    PubMed

    Daliri, Ayoub; Max, Ludo

    2015-04-01

    Stuttering is associated with atypical structural and functional connectivity in sensorimotor brain areas, in particular premotor, motor, and auditory regions. It remains unknown, however, which specific mechanisms of speech planning and execution are affected by these neurological abnormalities. To investigate pre-movement sensory modulation, we recorded 12 stuttering and 12 nonstuttering adults' auditory evoked potentials in response to probe tones presented prior to speech onset in a delayed-response speaking condition vs. no-speaking control conditions (silent reading; seeing nonlinguistic symbols). Findings indicate that, during speech movement planning, the nonstuttering group showed a statistically significant modulation of auditory processing (reduced N1 amplitude) that was not observed in the stuttering group. Thus, the obtained results provide electrophysiological evidence in support of the hypothesis that stuttering is associated with deficiencies in modulating the cortical auditory system during speech movement planning. This specific sensorimotor integration deficiency may contribute to inefficient feedback monitoring and, consequently, speech dysfluencies. PMID:25796060

  5. Cross-Modal Recruitment of Primary Visual Cortex by Auditory Stimuli in the Nonhuman Primate Brain: A Molecular Mapping Study

    PubMed Central

    Hirst, Priscilla; Javadi Khomami, Pasha; Gharat, Amol; Zangenehpour, Shahin

    2012-01-01

    Recent studies suggest that exposure to only one component of audiovisual events can lead to cross-modal cortical activation. However, it is not certain whether such crossmodal recruitment can occur in the absence of explicit conditioning, semantic factors, or long-term associations. A recent study demonstrated that crossmodal cortical recruitment can occur even after a brief exposure to bimodal stimuli without semantic association. In addition, the authors showed that the primary visual cortex is under such crossmodal influence. In the present study, we used molecular activity mapping of the immediate early gene zif268. We found that animals, which had previously been exposed to a combination of auditory and visual stimuli, showed increased number of active neurons in the primary visual cortex when presented with sounds alone. As previously implied, this crossmodal activation appears to be the result of implicit associations of the two stimuli, likely driven by their spatiotemporal characteristics; it was observed after a relatively short period of exposure (~45 min) and lasted for a relatively long period after the initial exposure (~1 day). These results suggest that the previously reported findings may be directly rooted in the increased activity of the neurons occupying the primary visual cortex. PMID:22792489

  6. Noise-gated encoding of slow inputs by auditory brain stem neurons with a low-threshold K+ current.

    PubMed

    Gai, Yan; Doiron, Brent; Kotak, Vibhakar; Rinzel, John

    2009-12-01

    Phasic neurons, which do not fire repetitively to steady depolarization, are found at various stages of the auditory system. Phasic neurons are commonly described as band-pass filters because they do not respond to low-frequency inputs even when the amplitude is large. However, we show that phasic neurons can encode low-frequency inputs when noise is present. With a low-threshold potassium current (I(KLT)), a phasic neuron model responds to rising and falling phases of a subthreshold low-frequency signal with white noise. When the white noise was low-pass filtered, the phasic model also responded to the signal's trough but still not to the peak. In contrast, a tonic neuron model fired mostly to the signal's peak. To test the model predictions, whole cell slice recordings were obtained in the medial (MSO) and lateral (LSO) superior olivary neurons in gerbil from postnatal day 10 (P10) to 22. The phasic MSO neurons with strong I(KLT), mostly from gerbils aged P17 or older, showed firing patterns consistent with the preceding predictions. Moreover, injecting a virtual I(KLT) into weak-phasic MSO and tonic LSO neurons with putative weak or no I(KLT) (from gerbils younger than P17) shifted the neural response from the signal's peak to the rising phase. These findings advance our knowledge about how noise gates the signal pathway and how phasic neurons encode slow envelopes of sounds with high-frequency carriers. PMID:19812289

  7. GABAB Receptor-Positive Modulators: Brain Region-Dependent Effects

    PubMed Central

    Advani, Tushar; Burke, Teresa F.; Cheng, Kejun; Rice, Kenner C.; Koek, Wouter

    2012-01-01

    This study examined the positive modulatory properties of 2,6-di-tert-butyl-4-(3-hydroxy-2,2-dimethyl-propyl)-phenol (CGP7930) and (R,S)-5,7-di-tert-butyl-3-hydroxy-3-trifluoromethyl-3H-benzofuran-2-one (rac-BHFF) at γ-aminobutyric acid B (GABAB) receptors in different brain regions. Using quantitative autoradiography, we measured GABAB receptor-stimulated binding of guanosine 5′-O-(3-[35S]thiotriphosphate) ([35S]GTPγS) to G proteins in medial prefrontal cortex (mPFC), hippocampus, and cerebellum. CGP7930 and rac-BHFF enhanced baclofen-stimulated [35S]GTPγS binding similarly in mPFC and hippocampus, but were more effective in cerebellum. CGP7930 (100 μM) increased [35S]GTPγS binding stimulated by baclofen (30 μM) from 29 to 241% above basal in mPFC and from 13 to 1530% above basal in cerebellum. Likewise, rac-BHFF (10 μM) increased baclofen-stimulated [35S]GTPγS binding more in cerebellum (from 13 to 1778% above basal) than in mPFC (from 29 to 514% above basal). rac-BHFF (10 μM) in combination with γ-hydroxybutyrate (20 mM) increased [35S]GTPγS binding in cerebellum but not in mPFC. rac-BHFF also enhanced the effects of 3-aminopropyl(diethoxymethyl)phosphinic acid (CGP35348). Consistent with its partial agonist properties, CGP35348 stimulated [35S]GTPγS binding in mPFC when given alone (to 18% above basal), but less extensively than baclofen (140% above basal), and antagonized baclofen when given together. CGP35348 (1 mM) in combination with rac-BHFF (100 μM) produced an increase in [35S]GTPγS binding that was larger in cerebellum (from 61 to 1260% above basal) than in mPFC (from 18 to 118% above basal). Taken together, the results show that GABAB receptor-positive modulators enhance [35S]GTPγS binding stimulated by GABAB receptor agonists in a brain region-dependent manner. This regionally selective enhancement is further evidence of pharmacologically distinct GABAB receptor populations, possibly allowing for more selective therapeutic targeting

  8. Intelligence and Regional Brain Volumes in Normal Controls.

    ERIC Educational Resources Information Center

    Flashman, Laura A.; Andreasen, Nancy C.; Flaum, Michael; Swayze, Victor W., II

    1998-01-01

    The relationship between brain size and intelligence was examined in 90 normal volunteers. Results support the notion of a modest relationship between brain size and measures of global intelligence and suggest diffuse brain involvement on performance tasks that require integration and use of multiple cognitive domains. (Author/SLD)

  9. Insult-induced adaptive plasticity of the auditory system

    PubMed Central

    Gold, Joshua R.; Bajo, Victoria M.

    2014-01-01

    The brain displays a remarkable capacity for both widespread and region-specific modifications in response to environmental challenges, with adaptive processes bringing about the reweighing of connections in neural networks putatively required for optimizing performance and behavior. As an avenue for investigation, studies centered around changes in the mammalian auditory system, extending from the brainstem to the cortex, have revealed a plethora of mechanisms that operate in the context of sensory disruption after insult, be it lesion-, noise trauma, drug-, or age-related. Of particular interest in recent work are those aspects of auditory processing which, after sensory disruption, change at multiple—if not all—levels of the auditory hierarchy. These include changes in excitatory, inhibitory and neuromodulatory networks, consistent with theories of homeostatic plasticity; functional alterations in gene expression and in protein levels; as well as broader network processing effects with cognitive and behavioral implications. Nevertheless, there abounds substantial debate regarding which of these processes may only be sequelae of the original insult, and which may, in fact, be maladaptively compelling further degradation of the organism's competence to cope with its disrupted sensory context. In this review, we aim to examine how the mammalian auditory system responds in the wake of particular insults, and to disambiguate how the changes that develop might underlie a correlated class of phantom disorders, including tinnitus and hyperacusis, which putatively are brought about through maladaptive neuroplastic disruptions to auditory networks governing the spatial and temporal processing of acoustic sensory information. PMID:24904256

  10. Intrahemispheric cortico-cortical connections of the human auditory cortex.

    PubMed

    Cammoun, Leila; Thiran, Jean Philippe; Griffa, Alessandra; Meuli, Reto; Hagmann, Patric; Clarke, Stephanie

    2015-11-01

    The human auditory cortex comprises the supratemporal plane and large parts of the temporal and parietal convexities. We have investigated the relevant intrahemispheric cortico-cortical connections using in vivo DSI tractography combined with landmark-based registration, automatic cortical parcellation and whole-brain structural connection matrices in 20 right-handed male subjects. On the supratemporal plane, the pattern of connectivity was related to the architectonically defined early-stage auditory areas. It revealed a three-tier architecture characterized by a cascade of connections from the primary auditory cortex to six adjacent non-primary areas and from there to the superior temporal gyrus. Graph theory-driven analysis confirmed the cascade-like connectivity pattern and demonstrated a strong degree of segregation and hierarchy within early-stage auditory areas. Putative higher-order areas on the temporal and parietal convexities had more widely spread local connectivity and long-range connections with the prefrontal cortex; analysis of optimal community structure revealed five distinct modules in each hemisphere. The pattern of temporo-parieto-frontal connectivity was partially asymmetrical. In conclusion, the human early-stage auditory cortical connectivity, as revealed by in vivo DSI tractography, has strong similarities with that of non-human primates. The modular architecture and hemispheric asymmetry in higher-order regions is compatible with segregated processing streams and lateralization of cognitive functions. PMID:25173473

  11. Analysis of gene expression in mouse brain regions after exposure to 1.9 GHz radiofrequency fields

    PubMed Central

    McNamee, James P.; Bellier, Pascale V.; Konkle, Anne T. M.; Thomas, Reuben; Wasoontarajaroen, Siriwat; Lemay, Eric; Gajda, Greg B.

    2016-01-01

    Abstract Purpose: To assess 1.9 GHz radiofrequency (RF) field exposure on gene expression within a variety of discrete mouse brain regions using whole genome microarray analysis. Materials and methods: Adult male C57BL/6 mice were exposed to 1.9 GHz pulse-modulated or continuous-wave RF fields for 4 h/day for 5 consecutive days at whole body average (WBA) specific absorption rates of 0 (sham), ∼0.2 W/kg and ∼1.4 W/kg. Total RNA was isolated from the auditory cortex, amygdala, caudate, cerebellum, hippocampus, hypothalamus, and medial prefrontal cortex and differential gene expression was assessed using Illumina MouseWG-6 (v2) BeadChip arrays. Validation of potentially responding genes was conducted by RT-PCR. Results: When analysis of gene expression was conducted within individual brain regions when controlling the false discovery rate (FDR), no differentially expressed genes were identified relative to the sham control. However, it must be noted that most fold changes among groups were observed to be less than 1.5-fold and this study had limited ability to detect such small changes. While some genes were differentially expressed without correction for multiple-comparisons testing, no consistent pattern of response was observed among different RF-exposure levels or among different RF-modulations. Conclusions: The current study provides the most comprehensive analysis of potential gene expression changes in the rodent brain in response to RF field exposure conducted to date. Within the exposure conditions and limitations of this study, no convincing evidence of consistent changes in gene expression was found in response to 1.9 GHz RF field exposure. PMID:27028625

  12. Regional research priorities in brain and nervous system disorders.

    PubMed

    Ravindranath, Vijayalakshmi; Dang, Hoang-Minh; Goya, Rodolfo G; Mansour, Hader; Nimgaonkar, Vishwajit L; Russell, Vivienne Ann; Xin, Yu

    2015-11-19

    The characteristics of neurological, psychiatric, developmental and substance-use disorders in low- and middle-income countries are unique and the burden that they have will be different from country to country. Many of the differences are explained by the wide variation in population demographics and size, poverty, conflict, culture, land area and quality, and genetics. Neurological, psychiatric, developmental and substance-use disorders that result from, or are worsened by, a lack of adequate nutrition and infectious disease still afflict much of sub-Saharan Africa, although disorders related to increasing longevity, such as stroke, are on the rise. In the Middle East and North Africa, major depressive disorders and post-traumatic stress disorder are a primary concern because of the conflict-ridden environment. Consanguinity is a serious concern that leads to the high prevalence of recessive disorders in the Middle East and North Africa and possibly other regions. The burden of these disorders in Latin American and Asian countries largely surrounds stroke and vascular disease, dementia and lifestyle factors that are influenced by genetics. Although much knowledge has been gained over the past 10 years, the epidemiology of the conditions in low- and middle-income countries still needs more research. Prevention and treatments could be better informed with more longitudinal studies of risk factors. Challenges and opportunities for ameliorating nervous-system disorders can benefit from both local and regional research collaborations. The lack of resources and infrastructure for health-care and related research, both in terms of personnel and equipment, along with the stigma associated with the physical or behavioural manifestations of some disorders have hampered progress in understanding the disease burden and improving brain health. Individual countries, and regions within countries, have specific needs in terms of research priorities. PMID:26580328

  13. Demonstration of prosthetic activation of central auditory pathways using ( sup 14 C)-2-deoxyglucose

    SciTech Connect

    Evans, D.A.; Niparko, J.K.; Altschuler, R.A.; Frey, K.A.; Miller, J.M. )

    1990-02-01

    The cochlear prosthesis is not applicable to patients who lack an implantable cochlea or an intact vestibulocochlear nerve. Direct electrical stimulation of the cochlear nucleus (CN) of the brain stem might provide a method for auditory rehabilitation of these patients. A penetrating CN electrode has been developed and tissue tolerance to this device demonstrated. This study was undertaken to evaluate metabolic activation of central nervous system (CNS) auditory tracts produced by such implants. Regional cerebral glucose use resulting from CN stimulation was estimated in a series of chronically implanted guinea pigs with the use of ({sup 14}C)-2-deoxyglucose (2-DG). Enhanced 2-DG uptake was observed in structures of the auditory tract. The activation of central auditory structures achieved with CN stimulation was similar to that produced by acoustic stimulation and by electrical stimulation of the modiolar portion of the auditory nerve in control groups. An interesting banding pattern was observed in the inferior colliculus following CN stimulation, as previously described with acoustic stimulation. This study demonstrates that functional metabolic activation of central auditory pathways can be achieved with a penetrating CNS auditory prosthesis.

  14. Brain Dynamics of Aging: Multiscale Variability of EEG Signals at Rest and during an Auditory Oddball Task1,2,3

    PubMed Central

    Sleimen-Malkoun, Rita; Perdikis, Dionysios; Müller, Viktor; Blanc, Jean-Luc; Huys, Raoul; Temprado, Jean-Jacques

    2015-01-01

    Abstract The present work focused on the study of fluctuations of cortical activity across time scales in young and older healthy adults. The main objective was to offer a comprehensive characterization of the changes of brain (cortical) signal variability during aging, and to make the link with known underlying structural, neurophysiological, and functional modifications, as well as aging theories. We analyzed electroencephalogram (EEG) data of young and elderly adults, which were collected at resting state and during an auditory oddball task. We used a wide battery of metrics that typically are separately applied in the literature, and we compared them with more specific ones that address their limits. Our procedure aimed to overcome some of the methodological limitations of earlier studies and verify whether previous findings can be reproduced and extended to different experimental conditions. In both rest and task conditions, our results mainly revealed that EEG signals presented systematic age-related changes that were time-scale-dependent with regard to the structure of fluctuations (complexity) but not with regard to their magnitude. Namely, compared with young adults, the cortical fluctuations of the elderly were more complex at shorter time scales, but less complex at longer scales, although always showing a lower variance. Additionally, the elderly showed signs of spatial, as well as between, experimental conditions dedifferentiation. By integrating these so far isolated findings across time scales, metrics, and conditions, the present study offers an overview of age-related changes in the fluctuation electrocortical activity while making the link with underlying brain dynamics. PMID:26464983

  15. Brain Dynamics of Aging: Multiscale Variability of EEG Signals at Rest and during an Auditory Oddball Task(1,2,3).

    PubMed

    Sleimen-Malkoun, Rita; Perdikis, Dionysios; Müller, Viktor; Blanc, Jean-Luc; Huys, Raoul; Temprado, Jean-Jacques; Jirsa, Viktor K

    2015-01-01

    The present work focused on the study of fluctuations of cortical activity across time scales in young and older healthy adults. The main objective was to offer a comprehensive characterization of the changes of brain (cortical) signal variability during aging, and to make the link with known underlying structural, neurophysiological, and functional modifications, as well as aging theories. We analyzed electroencephalogram (EEG) data of young and elderly adults, which were collected at resting state and during an auditory oddball task. We used a wide battery of metrics that typically are separately applied in the literature, and we compared them with more specific ones that address their limits. Our procedure aimed to overcome some of the methodological limitations of earlier studies and verify whether previous findings can be reproduced and extended to different experimental conditions. In both rest and task conditions, our results mainly revealed that EEG signals presented systematic age-related changes that were time-scale-dependent with regard to the structure of fluctuations (complexity) but not with regard to their magnitude. Namely, compared with young adults, the cortical fluctuations of the elderly were more complex at shorter time scales, but less complex at longer scales, although always showing a lower variance. Additionally, the elderly showed signs of spatial, as well as between, experimental conditions dedifferentiation. By integrating these so far isolated findings across time scales, metrics, and conditions, the present study offers an overview of age-related changes in the fluctuation electrocortical activity while making the link with underlying brain dynamics. PMID:26464983

  16. Adaptation to Vocal Expressions Reveals Multistep Perception of Auditory Emotion

    PubMed Central

    Maurage, Pierre; Rouger, Julien; Latinus, Marianne; Belin, Pascal

    2014-01-01

    The human voice carries speech as well as important nonlinguistic signals that influence our social interactions. Among these cues that impact our behavior and communication with other people is the perceived emotional state of the speaker. A theoretical framework for the neural processing stages of emotional prosody has suggested that auditory emotion is perceived in multiple steps (Schirmer and Kotz, 2006) involving low-level auditory analysis and integration of the acoustic information followed by higher-level cognition. Empirical evidence for this multistep processing chain, however, is still sparse. We examined this question using functional magnetic resonance imaging and a continuous carry-over design (Aguirre, 2007) to measure brain activity while volunteers listened to non-speech-affective vocalizations morphed on a continuum between anger and fear. Analyses dissociated neuronal adaptation effects induced by similarity in perceived emotional content between consecutive stimuli from those induced by their acoustic similarity. We found that bilateral voice-sensitive auditory regions as well as right amygdala coded the physical difference between consecutive stimuli. In contrast, activity in bilateral anterior insulae, medial superior frontal cortex, precuneus, and subcortical regions such as bilateral hippocampi depended predominantly on the perceptual difference between morphs. Our results suggest that the processing of vocal affect recognition is a multistep process involving largely distinct neural networks. Amygdala and auditory areas predominantly code emotion-related acoustic information while more anterior insular and prefrontal regions respond to the abstract, cognitive representation of vocal affect. PMID:24920615

  17. Functional and effective connectivity in an fMRI study of an auditory-related task.

    PubMed

    Caclin, Anne; Fonlupt, Pierre

    2006-05-01

    This study investigates the sets of brain areas that are functionally connected during an auditory goal-directed task. We used a paradigm including a resting state condition and an active condition, which consisted in active listening to the footsteps of walking humans. The regional brain activity was measured using fMRI and the adjusted values of activity in brain regions involved in the task were analysed using both principal component analysis and structural equation modelling. A first set of connected areas includes regions located in Heschl's gyrus, planum temporale, posterior superior temporal sulcus (in the so-called 'social cognition' area), and parietal lobe. This network could be responsible for the perceptual integration of the auditory signal. A second set encompassing frontal regions is related to attentional control. Dorsolateral- and medial-prefrontal cortex have mutual negative influences which are similar to those described during a visual goal-directed task [T. Chaminade & P. Fonlupt (2003) Eur. J. Neurosci., 18, 675-679.]. Moreover, the dorsolateral prefrontal cortex (DLPFC) exerts a positive influence on the auditory areas during the task, as well as a strong negative influence on the visual areas. These results show that: (i) the negative influence between the medial and lateral parts of the frontal cortex during a goal-directed task is not dependent on the input modality (visual or auditory), and (ii) the DLPFC activates the pathway of the relevant sensory modality and inhibits the nonrelevant sensory modality pathway. PMID:16706860

  18. Functional connectivity between face-movement and speech-intelligibility areas during auditory-only speech perception.

    PubMed

    Schall, Sonja; von Kriegstein, Katharina

    2014-01-01

    It has been proposed that internal simulation of the talking face of visually-known speakers facilitates auditory speech recognition. One prediction of this view is that brain areas involved in auditory-only speech comprehension interact with visual face-movement sensitive areas, even under auditory-only listening conditions. Here, we test this hypothesis using connectivity analyses of functional magnetic resonance imaging (fMRI) data. Participants (17 normal participants, 17 developmental prosopagnosics) first learned six speakers via brief voice-face or voice-occupation training (<2 min/speaker). This was followed by an auditory-only speech recognition task and a control task (voice recognition) involving the learned speakers' voices in the MRI scanner. As hypothesized, we found that, during speech recognition, familiarity with the speaker's face increased the functional connectivity between the face-movement sensitive posterior superior temporal sulcus (STS) and an anterior STS region that supports auditory speech intelligibility. There was no difference between normal participants and prosopagnosics. This was expected because previous findings have shown that both groups use the face-movement sensitive STS to optimize auditory-only speech comprehension. Overall, the present findings indicate that learned visual information is integrated into the analysis of auditory-only speech and that this integration results from the interaction of task-relevant face-movement and auditory speech-sensitive areas. PMID:24466026

  19. Emotion modulates activity in the 'what' but not 'where' auditory processing pathway.

    PubMed

    Kryklywy, James H; Macpherson, Ewan A; Greening, Steven G; Mitchell, Derek G V

    2013-11-15

    Auditory cortices can be separated into dissociable processing pathways similar to those observed in the visual domain. Emotional stimuli elicit enhanced neural activation within sensory cortices when compared to neutral stimuli. This effect is particularly notable in the ventral visual stream. Little is known, however, about how emotion interacts with dorsal processing streams, and essentially nothing is known about the impact of emotion on auditory stimulus localization. In the current study, we used fMRI in concert with individualized auditory virtual environments to investigate the effect of emotion during an auditory stimulus localization task. Surprisingly, participants were significantly slower to localize emotional relative to neutral sounds. A separate localizer scan was performed to isolate neural regions sensitive to stimulus location independent of emotion. When applied to the main experimental task, a significant main effect of location, but not emotion, was found in this ROI. A whole-brain analysis of the data revealed that posterior-medial regions of auditory cortex were modulated by sound location; however, additional anterior-lateral areas of auditory cortex demonstrated enhanced neural activity to emotional compared to neutral stimuli. The latter region resembled areas described in dual pathway models of auditory processing as the 'what' processing stream, prompting a follow-up task to generate an identity-sensitive ROI (the 'what' pathway) independent of location and emotion. Within this region, significant main effects of location and emotion were identified, as well as a significant interaction. These results suggest that emotion modulates activity in the 'what,' but not the 'where,' auditory processing pathway. PMID:23711533

  20. MARGA: multispectral adaptive region growing algorithm for brain extraction on axial MRI.

    PubMed

    Roura, Eloy; Oliver, Arnau; Cabezas, Mariano; Vilanova, Joan C; Rovira, Alex; Ramió-Torrentà, Lluís; Lladó, Xavier

    2014-02-01

    Brain extraction, also known as skull stripping, is one of the most important preprocessing steps for many automatic brain image analysis. In this paper we present a new approach called Multispectral Adaptive Region Growing Algorithm (MARGA) to perform the skull stripping process. MARGA is based on a region growing (RG) algorithm which uses the complementary information provided by conventional magnetic resonance images (MRI) such as T1-weighted and T2-weighted to perform the brain segmentation. MARGA can be seen as an extension of the skull stripping method proposed by Park and Lee (2009) [1], enabling their use in both axial views and low quality images. Following the same idea, we first obtain seed regions that are then spread using a 2D RG algorithm which behaves differently in specific zones of the brain. This adaptation allows to deal with the fact that middle MRI slices have better image contrast between the brain and non-brain regions than superior and inferior brain slices where the contrast is smaller. MARGA is validated using three different databases: 10 simulated brains from the BrainWeb database; 2 data sets from the National Alliance for Medical Image Computing (NAMIC) database, the first one consisting in 10 normal brains and 10 brains of schizophrenic patients acquired with a 3T GE scanner, and the second one consisting in 5 brains from lupus patients acquired with a 3T Siemens scanner; and 10 brains of multiple sclerosis patients acquired with a 1.5T scanner. We have qualitatively and quantitatively compared MARGA with the well-known Brain Extraction Tool (BET), Brain Surface Extractor (BSE) and Statistical Parametric Mapping (SPM) approaches. The obtained results demonstrate the validity of MARGA, outperforming the results of those standard techniques. PMID:24380649

  1. [Brain stem auditory and visual evoked potentials in children and adolescents with Guillain-Barré syndrome].

    PubMed

    Zgorzalewicz, Małgorzata; Zielińska, Mariola; Kilarski, Dariusz

    2004-01-01

    amplitudes were found. These parameters were statistically significant in comparison to the control group. VEP results suggest the involvement of visual pathway in examined children and adolescents. EP can be used as a complementary method for the evaluation of clinically silent lesion in the auditory and optical tracts in GBS. PMID:15045865

  2. Carnosine reverses the aging-induced down regulation of brain regional serotonergic system.

    PubMed

    Banerjee, Soumyabrata; Ghosh, Tushar K; Poddar, Mrinal K

    2015-12-01

    The purpose of the present investigation was to study the role of carnosine, an endogenous dipeptide biomolecule, on brain regional (cerebral cortex, hippocampus, hypothalamus and pons-medulla) serotonergic system during aging. Results showed an aging-induced brain region specific significant (a) increase in Trp (except cerebral cortex) and their 5-HIAA steady state level with an increase in their 5-HIAA accumulation and declination, (b) decrease in their both 5-HT steady state level and 5-HT accumulation (except cerebral cortex). A significant decrease in brain regional 5-HT/Trp ratio (except cerebral cortex) and increase in 5-HIAA/5-HT ratio were also observed during aging. Carnosine at lower dosages (0.5-1.0μg/Kg/day, i.t. for 21 consecutive days) didn't produce any significant response in any of the brain regions, but higher dosages (2.0-2.5μg/Kg/day, i.t. for 21 consecutive days) showed a significant response on those aging-induced brain regional serotonergic parameters. The treatment with carnosine (2.0μg/Kg/day, i.t. for 21 consecutive days), attenuated these brain regional aging-induced serotonergic parameters and restored towards their basal levels that observed in 4 months young control rats. These results suggest that carnosine attenuates and restores the aging-induced brain regional down regulation of serotonergic system towards that observed in young rats' brain regions. PMID:26364584

  3. Neural dynamics of phonological processing in the dorsal auditory stream.

    PubMed

    Liebenthal, Einat; Sabri, Merav; Beardsley, Scott A; Mangalathu-Arumana, Jain; Desai, Anjali

    2013-09-25

    Neuroanatomical models hypothesize a role for the dorsal auditory pathway in phonological processing as a feedforward efferent system (Davis and Johnsrude, 2007; Rauschecker and Scott, 2009; Hickok et al., 2011). But the functional organization of the pathway, in terms of time course of interactions between auditory, somatosensory, and motor regions, and the hemispheric lateralization pattern is largely unknown. Here, ambiguous duplex syllables, with elements presented dichotically at varying interaural asynchronies, were used to parametrically modulate phonological processing and associated neural activity in the human dorsal auditory stream. Subjects performed syllable and chirp identification tasks, while event-related potentials and functional magnetic resonance images were concurrently collected. Joint independent component analysis was applied to fuse the neuroimaging data and study the neural dynamics of brain regions involved in phonological processing with high spatiotemporal resolution. Results revealed a highly interactive neural network associated with phonological processing, composed of functional fields in posterior temporal gyrus (pSTG), inferior parietal lobule (IPL), and ventral central sulcus (vCS) that were engaged early and almost simultaneously (at 80-100 ms), consistent with a direct influence of articulatory somatomotor areas on phonemic perception. Left hemispheric lateralization was observed 250 ms earlier in IPL and vCS than pSTG, suggesting that functional specialization of somatomotor (and not auditory) areas determined lateralization in the dorsal auditory pathway. The temporal dynamics of the dorsal auditory pathway described here offer a new understanding of its functional organization and demonstrate that temporal information is essential to resolve neural circuits underlying complex behaviors. PMID:24068810

  4. Auditory system

    NASA Technical Reports Server (NTRS)

    Ades, H. W.

    1973-01-01

    The physical correlations of hearing, i.e. the acoustic stimuli, are reported. The auditory system, consisting of external ear, middle ear, inner ear, organ of Corti, basilar membrane, hair cells, inner hair cells, outer hair cells, innervation of hair cells, and transducer mechanisms, is discussed. Both conductive and sensorineural hearing losses are also examined.

  5. Auditory synesthesias.

    PubMed

    Afra, Pegah

    2015-01-01

    Synesthesia is experienced when sensory stimulation of one sensory modality (the inducer) elicits an involuntary or automatic sensation in another sensory modality or different aspect of the same sensory modality (the concurrent). Auditory synesthesias (AS) occur when auditory stimuli trigger a variety of concurrents, or when non-auditory sensory stimulations trigger auditory synesthetic perception. The AS are divided into three types: developmental, acquired, and induced. Developmental AS are not a neurologic disorder but a different way of experiencing one's environment. They are involuntary and highly consistent experiences throughout one's life. Acquired AS have been reported in association with neurologic diseases that cause deafferentation of anterior optic pathways, with pathologic lesions affecting the central nervous system (CNS) outside of the optic pathways, as well as non-lesional cases associated with migraine, and epilepsy. It also has been reported with mood disorders as well as a single idiopathic case. Induced AS has been reported in experimental and postsurgical blindfolding, as well as intake of hallucinogenics or psychedelics. In this chapter the three different types of synesthesia, their characteristics, and phenomologic differences, as well as their possible neural mechanisms are discussed. PMID:25726281

  6. Generators and Connectivity of the Early Auditory Evoked Gamma Band Response.

    PubMed

    Polomac, Nenad; Leicht, Gregor; Nolte, Guido; Andreou, Christina; Schneider, Till R; Steinmann, Saskia; Engel, Andreas K; Mulert, Christoph

    2015-11-01

    High frequency oscillations in the gamma range are known to be involved in early stages of auditory information processing in terms of synchronization of brain regions, e.g., in cognitive functions. It has been shown using EEG source localisation, as well as simultaneously recorded EEG-fMRI, that the auditory evoked gamma-band response (aeGBR) is modulated by attention. In addition to auditory cortex activity a dorsal anterior cingulate cortex (dACC) generator could be involved. In the present study we investigated aeGBR magnetic fields using magnetoencephalography (MEG). We aimed to localize the aeGBR sources and its connectivity features in relation to mental effort. We investigated the aeGBR magnetic fields in 13 healthy participants using a 275-channel CTF-MEG system. The experimental paradigms were two auditory choice reaction tasks with different difficulties and demands for mental effort. We performed source localization with eLORETA and calculated the aeGBR lagged phase synchronization between bilateral auditory cortices and frontal midline structures. The eLORETA analysis revealed sources of the aeGBR within bilateral auditory cortices and in frontal midline structures of the brain including the dACC. Compared to the control condition the dACC source activity was found to be significantly stronger during the performance of the cognitively demanding task. Moreover, this task involved a significantly stronger functional connectivity between auditory cortices and dACC. In accordance with previous EEG and EEG-fMRI investigations, our study confirms an aeGBR generator in the dACC by means of MEG and suggests its involvement in the effortful processing of auditory stimuli. PMID:25926268

  7. Distortion product otoacoustic emissions and auditory evoked potentials in the hedgehog tenrec, Echinops telfairi.

    PubMed

    Drexl, Markus; Faulstich, Michael; Von Stebut, Boris; Radtke-Schuller, Susanne; Kössl, Manfred

    2003-12-01

    The hedgehog tenrec, Echinops telfairi, has certain basal mammalian features, like a cloaca and a sparsely differentiated brain with smooth cerebral hemispheres. The peripheral auditory capabilities of this species were investigated by means of distortion product otoacoustic emissions (DPOAE). For comparison, we determined auditory evoked potentials (AEP) in the inferior colliculus and the auditory cortex. Both methods show that the auditory range of E. telfairi extends well into ultrasonic frequencies, with a region of highest sensitivity at around 16 kHz. The total auditory range spans about 4 octaves at 40 dB SPL. The low-frequency limit of auditory processing is found at frequencies of about 2-3 kHz. The DPOAE and the AEP thresholds of E. telfairi do not run fully parallel in the high-frequency range. For a threshold value of 40 dB SPL, cochlear mechanical thresholds as measured with DPOAE extend up to 50 kHz, whereas neuronal thresholds reach the high-frequency limit at about 30 kHz. Frequency tuning, as assessed from DPOAE suppression tuning curves, was low to moderate with Q(10 dB) values ranging from 1.7 to 8. The lack of discontinuity in the group delay (derived from DPOAE measurements) reveals that cochlear frequency representation is tonotopic without any region of specialized mechanical tuning. PMID:14569428

  8. Harmonic Training and the Formation of Pitch Representation in a Neural Network Model of the Auditory Brain

    PubMed Central

    Ahmad, Nasir; Higgins, Irina; Walker, Kerry M. M.; Stringer, Simon M.

    2016-01-01

    Attempting to explain the perceptual qualities of pitch has proven to be, and remains, a difficult problem. The wide range of sounds which elicit pitch and a lack of agreement across neurophysiological studies on how pitch is encoded by the brain have made this attempt more difficult. In describing the potential neural mechanisms by which pitch may be processed, a number of neural networks have been proposed and implemented. However, no unsupervised neural networks with biologically accurate cochlear inputs have yet been demonstrated. This paper proposes a simple system in which pitch representing neurons are produced in a biologically plausible setting. Purely unsupervised regimes of neural network learning are implemented and these prove to be sufficient in identifying the pitch of sounds with a variety of spectral profiles, including sounds with missing fundamental frequencies and iterated rippled noises. PMID:27047368

  9. Harmonic Training and the Formation of Pitch Representation in a Neural Network Model of the Auditory Brain.

    PubMed

    Ahmad, Nasir; Higgins, Irina; Walker, Kerry M M; Stringer, Simon M

    2016-01-01

    Attempting to explain the perceptual qualities of pitch has proven to be, and remains, a difficult problem. The wide range of sounds which elicit pitch and a lack of agreement across neurophysiological studies on how pitch is encoded by the brain have made this attempt more difficult. In describing the potential neural mechanisms by which pitch may be processed, a number of neural networks have been proposed and implemented. However, no unsupervised neural networks with biologically accurate cochlear inputs have yet been demonstrated. This paper proposes a simple system in which pitch representing neurons are produced in a biologically plausible setting. Purely unsupervised regimes of neural network learning are implemented and these prove to be sufficient in identifying the pitch of sounds with a variety of spectral profiles, including sounds with missing fundamental frequencies and iterated rippled noises. PMID:27047368

  10. Auditory short-term memory in the primate auditory cortex.

    PubMed

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26541581

  11. Impaired auditory selective attention ameliorated by cognitive training with graded exposure to noise in patients with traumatic brain injury.

    PubMed

    Dundon, Neil M; Dockree, Suvi P; Buckley, Vanessa; Merriman, Niamh; Carton, Mary; Clarke, Sarah; Roche, Richard A P; Lalor, Edmund C; Robertson, Ian H; Dockree, Paul M

    2015-08-01

    Patients who suffer traumatic brain injury frequently report difficulty concentrating on tasks and completing routine activities in noisy and distracting environments. Such impairments can have long-term negative psychosocial consequences. A cognitive control function that may underlie this impairment is the capacity to select a goal-relevant signal for further processing while safeguarding it from irrelevant noise. A paradigmatic investigation of this problem was undertaken using a dichotic listening task (study 1) in which comprehension of a stream of speech to one ear was measured in the context of increasing interference from a second stream of irrelevant speech to the other ear. Controls showed an initial decline in performance in the presence of competing speech but thereafter showed adaptation to increasing audibility of irrelevant speech, even at the highest levels of noise. By contrast, patients showed linear decline in performance with increasing noise. Subsequently attempts were made to ameliorate this deficit (study 2) using a cognitive training procedure based on attention process training (APT) that included graded exposure to irrelevant noise over the course of training. Patients were assigned to adaptive and non-adaptive training schedules or to a no-training control group. Results showed that both types of training drove improvements in the dichotic listening and in naturalistic tasks of performance in noise. Improvements were also seen on measures of selective attention in the visual domain suggesting transfer of training. We also observed augmentation of event-related potentials (ERPs) linked to target processing (P3b) but no change in ERPs evoked by distractor stimuli (P3a) suggesting that training heightened tuning of target signals, as opposed to gating irrelevant noise. No changes in any of the above measures were observed in a no-training control group. Together these findings present an ecologically valid approach to measure selective

  12. Electrophysiological study of auditory development.

    PubMed

    Lippé, S; Martinez-Montes, E; Arcand, C; Lassonde, M

    2009-12-15

    Cortical auditory evoked potential (CAEP) testing, a non-invasive technique, is widely employed to study auditory brain development. The aim of this study was to investigate the development of the auditory electrophysiological signal without addressing specific abilities such as speech or music discrimination. We were interested in the temporal and spectral domains of conventional auditory evoked potentials. We analyzed cerebral responses to auditory stimulation (broadband noises) in 40 infants and children (1 month to 5 years 6 months) and 10 adults using high-density electrophysiological recording. We hypothesized that the adult auditory response has precursors that can be identified in infant and child responses. Results confirm that complex adult CAEP responses and spectral activity patterns appear after 5 years, showing decreased involvement of lower frequencies and increased involvement of higher frequencies. In addition, time-locked response to stimulus and event-related spectral pertubation across frequencies revealed alpha and beta band contributions to the CAEP of infants and toddlers before mutation to the beta and gamma band activity of the adult response. A detailed analysis of electrophysiological responses to a perceptual stimulation revealed general development patterns and developmental precursors of the adult response. PMID:19665050

  13. Speech motor brain regions are differentially recruited during perception of native and foreign-accented phonemes for first and second language listeners

    PubMed Central

    Callan, Daniel; Callan, Akiko; Jones, Jeffery A.

    2014-01-01

    Brain imaging studies indicate that speech motor areas are recruited for auditory speech perception, especially when intelligibility is low due to environmental noise or when speech is accented. The purpose of the present study was to determine the relative contribution of brain regions to the processing of speech containing phonetic categories from one's own language, speech with accented samples of one's native phonetic categories, and speech with unfamiliar phonetic categories. To that end, native English and Japanese speakers identified the speech sounds /r/ and /l/ that were produced by native English speakers (unaccented) and Japanese speakers (foreign-accented) while functional magnetic resonance imaging measured their brain activity. For native English speakers, the Japanese accented speech was more difficult to categorize than the unaccented English speech. In contrast, Japanese speakers have difficulty distinguishing between /r/ and /l/, so both the Japanese accented and English unaccented speech were difficult to categorize. Brain regions involved with listening to foreign-accented productions of a first language included primarily the right cerebellum, left ventral inferior premotor cortex PMvi, and Broca's area. Brain regions most involved with listening to a second-language phonetic contrast (foreign-accented and unaccented productions) also included the left PMvi and the right cerebellum. Additionally, increased activity was observed in the right PMvi, the left and right ventral superior premotor cortex PMvs, and the left cerebellum. These results support a role for speech motor regions during the perception of foreign-accented native speech and for perception of difficult second-language phonetic contrasts. PMID:25232302

  14. Unconscious word processing engages a distributed network of brain regions.

    PubMed

    Diaz, Michele T; McCarthy, Gregory

    2007-11-01

    A briefly exposed visual stimulus may not be consciously perceived if it is preceded and followed by a dissimilar visual pattern or mask. Despite the subject's lack of awareness, prior behavioral studies have shown that such masked stimuli, nevertheless, engage domain-specific processes [Dehaene, S., Naccache, L., Cohen, L., Le Bihan, D., Mangin, J.-F., Poline, J.-B., et al. Cerebral mechanisms of word masking and unconscious repetition priming. Nature Neuroscience, 4, 752-758, 2001; Bar, M., & Biederman, I. Subliminal visual priming. Psychological Science, 9, 464-469, 1998; Dehaene, S., Naccache, L., Le Clec'H, G., Koechlin, E., Mueller, M., Dehaene-Lambertz, G., et al. Imaging unconscious semantic priming. Nature, 395, 597-600, 1998; Whalen, P. J., Rauch, S. L., Etcoff, N. L., McInerney, S. C., Lee, M. B., & Jenike, M. A. Masked presentations of emotional facial expressions modulate amygdala activity without explicit knowledge. Journal of Neuroscience, 18, 411-418, 1998; Marcel, A. J. Conscious and unconscious perception: Experiments on visual masking and word recognition. Cognitive Psychology, 15, 197-237, 1983]. Masking thus provides a method for identifying language processes that are preattentive and automatic. Functional magnetic resonance imaging used in concert with masking may identify brain regions engaged by these unconscious language processes. In an adaptation design, subjects viewed a continuous stream of masked words and masked nonwords while performing an unrelated detection task, in which they were asked to make a response to a visible colored nonword stimulus (i.e., ampersands in red or blue font). Most trials were masked nonwords and masked words were presented once every 12-15 sec. The task ensured participant engagement, while the masked nonword baseline controlled for perceptual and orthographic processing. Participants were naïve to the purpose of the experiment and testing indicated that they did not consciously perceive either the words

  15. Identification of a set of genes showing regionally enriched expression in the mouse brain

    PubMed Central

    D'Souza, Cletus A; Chopra, Vikramjit; Varhol, Richard; Xie, Yuan-Yun; Bohacec, Slavita; Zhao, Yongjun; Lee, Lisa LC; Bilenky, Mikhail; Portales-Casamar, Elodie; He, An; Wasserman, Wyeth W; Goldowitz, Daniel; Marra, Marco A; Holt, Robert A; Simpson, Elizabeth M; Jones, Steven JM

    2008-01-01

    Background The Pleiades Promoter Project aims to improve gene therapy by designing human mini-promoters (< 4 kb) that drive gene expression in specific brain regions or cell-types of therapeutic interest. Our goal was to first identify genes displaying regionally enriched expression in the mouse brain so that promoters designed from orthologous human genes can then be tested to drive reporter expression in a similar pattern in the mouse brain. Results We have utilized LongSAGE to identify regionally enriched transcripts in the adult mouse brain. As supplemental strategies, we also performed a meta-analysis of published literature and inspected the Allen Brain Atlas in situ hybridization data. From a set of approximately 30,000 mouse genes, 237 were identified as showing specific or enriched expression in 30 target regions of the mouse brain. GO term over-representation among these genes revealed co-involvement in various aspects of central nervous system development and physiology. Conclusion Using a multi-faceted expression validation approach, we have identified mouse genes whose human orthologs are good candidates for design of mini-promoters. These mouse genes represent molecular markers in several discrete brain regions/cell-types, which could potentially provide a mechanistic explanation of unique functions performed by each region. This set of markers may also serve as a resource for further studies of gene regulatory elements influencing brain expression. PMID:18625066

  16. Long-term recovery from hippocampal-related behavioral and biochemical abnormalities induced by noise exposure during brain development. Evaluation of auditory pathway integrity.

    PubMed

    Uran, S L; Gómez-Casati, M E; Guelman, L R

    2014-10-01

    Sound is an important part of man's contact with the environment and has served as critical means for survival throughout his evolution. As a result of exposure to noise, physiological functions such as those involving structures of the auditory and non-auditory systems might be damaged. We have previously reported that noise-exposed developing rats elicited hippocampal-related histological, biochemical and behavioral changes. However, no data about the time lapse of these changes were reported. Moreover, measurements of auditory pathway function were not performed in exposed animals. Therefore, with the present work, we aim to test the onset and the persistence of the different extra-auditory abnormalities observed in noise-exposed rats and to evaluate auditory pathway integrity. Male Wistar rats of 15 days were exposed to moderate noise levels (95-97 dB SPL, 2 h a day) during one day (acute noise exposure, ANE) or during 15 days (sub-acute noise exposure, SANE). Hippocampal biochemical determinations as well as short (ST) and long term (LT) behavioral assessments were performed. In addition, histological and functional evaluations of the auditory pathway were carried out in exposed animals. Our results show that hippocampal-related behavioral and biochemical changes (impairments in habituation, recognition and associative memories as well as distortion of anxiety-related behavior, decreases in reactive oxygen species (ROS) levels and increases in antioxidant enzymes activities) induced by noise exposure were almost completely restored by PND 90. In addition, auditory evaluation shows that increased cochlear thresholds observed in exposed rats were re-established at PND 90, although with a remarkable supra-threshold amplitude reduction. These data suggest that noise-induced hippocampal and auditory-related alterations are mostly transient and that the effects of noise on the hippocampus might be, at least in part, mediated by the damage on the auditory pathway

  17. Intrinsic firing properties in the avian auditory brain stem allow both integration and encoding of temporally modulated noisy inputs in vitro.

    PubMed

    Kreeger, Lauren J; Arshed, Arslaan; MacLeod, Katrina M

    2012-11-01

    The intrinsic properties of tonically firing neurons in the cochlear nucleus contribute to representing average sound intensity by favoring synaptic integration across auditory nerve inputs, reducing phase locking to fine temporal acoustic structure and enhancing envelope locking. To determine whether tonically firing neurons of the avian cochlear nucleus angularis (NA) resemble ideal integrators, we investigated their firing responses to noisy current injections during whole cell patch-clamp recordings in brain slices. One subclass of neurons (36% of tonically firing neurons, mainly subtype tonic III) showed no significant changes in firing rate with noise fluctuations, acting like pure integrators. In contrast, many tonically firing neurons (>60%, mainly subtype tonic I or II) showed a robust sensitivity to noisy current fluctuations, increasing their firing rates with increased fluctuation amplitudes. For noise-sensitive tonic neurons, the firing rate vs. average current curves with noise had larger maximal firing rates, lower gains, and wider dynamic ranges compared with FI curves for current steps without noise. All NA neurons showed fluctuation-driven patterning of spikes with a high degree of temporal reliability and millisecond spike time precision. Single-spiking neurons in NA also responded to noisy currents with higher firing rates and reliable spike trains, although less precisely than nucleus magnocellularis neurons. Thus some NA neurons function as integrators by encoding average input levels over wide dynamic ranges regardless of current fluctuations, others detect the degree of coherence in the inputs, and most encode the temporal patterns contained in their inputs with a high degree of precision. PMID:22914650

  18. Repetitive transcranial magnetic stimulation over frontal eye fields disrupts visually cued auditory attention.

    PubMed

    Smith, Daniel T; Jackson, Stephen R; Rorden, Chris

    2009-04-01

    Voluntary eye movements and covert shifts of visual attention activate the same brain regions. Specifically, the intraparietal sulcus and the frontal eye fields (FEF) appear to be involved both with generating voluntary saccades as well with attending to a peripheral spatial location. Furthermore, these regions appear to be required by both tasks--functional disruption of these regions impairs both tasks. Therefore, it appears that the targeting system that allows us to plan saccades is the same system that allows us to covertly track peripheral visual information. Recent neuroimaging studies suggest that these brain regions are also activated when participants engage in auditory spatial attention tasks. However, it remains unclear whether these regions are required by these tasks. We used repetitive transcranial magnetic stimulation (rTMS) to disrupt the FEF while participants performed an auditory localization task. On each trial, a visual cue directed attention to the probable laterality of the auditory target, and the participant decided whether the subsequent target sound came from an upper or lower speaker. In the absence of TMS, individuals were faster to respond to targets that occurred on the cued side (valid trials) than when the target appears contralaterally to the cued side (invalid side). TMS interfered with this effect, such that the costs associated with ipsilateral invalidly cued targets were substantially reduced. These results suggest that the eye-movement system is needed for normal auditory attention. PMID:20502626

  19. Mapping Individual Brain Networks Using Statistical Similarity in Regional Morphology from MRI

    PubMed Central

    Kong, Xiang-zhen; Liu, Zhaoguo; Huang, Lijie; Wang, Xu; Yang, Zetian; Zhou, Guangfu; Zhen, Zonglei; Liu, Jia

    2015-01-01

    Representing brain morphology as a network has the advantage that the regional morphology of ‘isolated’ structures can be described statistically based on graph theory. However, very few studies have investigated brain morphology from the holistic perspective of complex networks, particularly in individual brains. We proposed a new network framework for individual brain morphology. Technically, in the new network, nodes are defined as regions based on a brain atlas, and edges are estimated using our newly-developed inter-regional relation measure based on regional morphological distributions. This implementation allows nodes in the brain network to be functionally/anatomically homogeneous but different with respect to shape and size. We first demonstrated the new network framework in a healthy sample. Thereafter, we studied the graph-theoretical properties of the networks obtained and compared the results with previous morphological, anatomical, and functional networks. The robustness of the method was assessed via measurement of the reliability of the network metrics using a test-retest dataset. Finally, to illustrate potential applications, the networks were used to measure age-related changes in commonly used network metrics. Results suggest that the proposed method could provide a concise description of brain organization at a network level and be used to investigate interindividual variability in brain morphology from the perspective of complex networks. Furthermore, the method could open a new window into modeling the complexly distributed brain and facilitate the emerging field of human connectomics. PMID:26536598

  20. Quantitative Expression Profile of Distinct Functional Regions in the Adult Mouse Brain

    PubMed Central

    Nagano, Mamoru; Uno, Kenichiro D.; Tsujino, Kaori; Hanashima, Carina; Shigeyoshi, Yasufumi; Ueda, Hiroki R.

    2011-01-01

    The adult mammalian brain is composed of distinct regions with specialized roles including regulation of circadian clocks, feeding, sleep/awake, and seasonal rhythms. To find quantitative differences of expression among such various brain regions, we conducted the BrainStars (B*) project, in which we profiled the genome-wide expression of ∼50 small brain regions, including sensory centers, and centers for motion, time, memory, fear, and feeding. To avoid confounds from temporal differences in gene expression, we sampled each region every 4 hours for 24 hours, and pooled the samples for DNA-microarray assays. Therefore, we focused on spatial differences in gene expression. We used informatics to identify candidate genes with expression changes showing high or low expression in specific regions. We also identified candidate genes with stable expression across brain regions that can be used as new internal control genes, and ligand-receptor interactions of neurohormones and neurotransmitters. Through these analyses, we found 8,159 multi-state genes, 2,212 regional marker gene candidates for 44 small brain regions, 915 internal control gene candidates, and 23,864 inferred ligand-receptor interactions. We also found that these sets include well-known genes as well as novel candidate genes that might be related to specific functions in brain regions. We used our findings to develop an integrated database (http://brainstars.org/) for exploring genome-wide expression in the adult mouse brain, and have made this database openly accessible. These new resources will help accelerate the functional analysis of the mammalian brain and the elucidation of its regulatory network systems. PMID:21858037

  1. Listen to Yourself: The Medial Prefrontal Cortex Modulates Auditory Alpha Power During Speech Preparation.

    PubMed

    Müller, Nadia; Leske, Sabine; Hartmann, Thomas; Szebényi, Szabolcs; Weisz, Nathan

    2015-11-01

    How do we process stimuli that stem from the external world and stimuli that are self-generated? In the case of voice perception it has been shown that evoked activity elicited by self-generated sounds is suppressed compared with the same sounds played-back externally. We here wanted to reveal whether neural excitability of the auditory cortex-putatively reflected in local alpha band power--is modulated already prior to speech onset, and which brain regions may mediate such a top-down preparatory response. In the left auditory cortex we show that the typical alpha suppression found when participants prepare to listen disappears when participants expect a self-spoken sound. This suggests an inhibitory adjustment of auditory cortical activity already before sound onset. As a second main finding we demonstrate that the medial prefrontal cortex, a region known for self-referential processes, mediates these condition-specific alpha power modulations. This provides crucial insights into how higher-order regions prepare the auditory cortex for the processing of self-generated sounds. Furthermore, the mechanism outlined could provide further explanations to self-referential phenomena, such as "tickling yourself". Finally, it has implications for the so-far unsolved question of how auditory alpha power is mediated by higher-order regions in a more general sense. PMID:24904068

  2. Transcriptome analyses of adult mouse brain reveal enrichment of lncRNAs in specific brain regions and neuronal populations

    PubMed Central

    Kadakkuzha, Beena M.; Liu, Xin-An; McCrate, Jennifer; Shankar, Gautam; Rizzo, Valerio; Afinogenova, Alina; Young, Brandon; Fallahi, Mohammad; Carvalloza, Anthony C.; Raveendra, Bindu; Puthanveettil, Sathyanarayanan V.

    2015-01-01

    Despite the importance of the long non-coding RNAs (lncRNAs) in regulating biological functions, the expression profiles of lncRNAs in the sub-regions of the mammalian brain and neuronal populations remain largely uncharacterized. By analyzing RNASeq datasets, we demonstrate region specific enrichment of populations of lncRNAs and mRNAs in the mouse hippocampus and pre-frontal cortex (PFC), the two major regions of the brain involved in memory storage and neuropsychiatric disorders. We identified 2759 lncRNAs and 17,859 mRNAs in the hippocampus and 2561 lncRNAs and 17,464 mRNAs expressed in the PFC. The lncRNAs identified correspond to ~14% of the transcriptome of the hippocampus and PFC and ~70% of the lncRNAs annotated in the mouse genome (NCBIM37) and are localized along the chromosomes as varying numbers of clusters. Importantly, we also found that a few of the tested lncRNA-mRNA pairs that share a genomic locus display specific co-expression in a region-specific manner. Furthermore, we find that sub-regions of the brain and specific neuronal populations have characteristic lncRNA expression signatures. These results reveal an unexpected complexity of the lncRNA expression in the mouse brain. PMID:25798087

  3. Multi-sensory integration in brainstem and auditory cortex.

    PubMed

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience

  4. Multi-sensory integration in brainstem and auditory cortex

    PubMed Central

    Basura, Gregory J.; Koehler, Seth D.; Shore, Susan E.

    2012-01-01

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), similar auditory-somatosensory integration has been described in the normal system (Lakatos et al. 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al. 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, & 40ms), and greater suppression at 20ms pairing-intervals for single unit responses.. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. PMID:22995545

  5. The robo-pigeon based on the multiple brain regions synchronization implanted microelectrodes.

    PubMed

    Huai, Rui-Tuo; Yang, Jun-Qing; Wang, Hui

    2016-07-01

    Almost all multichannel microelectrodes are only applied to the same nucleus. The multiple brain regions synchronization implanted microelectrodes can be implanted in the several brain regions at the same time, when used in the robo-animal, which can reduce the operation process, shorten animals operation time. Due to electrode position relatively fixed, errors caused by each separately implanted electrode were reduced and the animal control effect was greatly increased compared to the original electrodes. The electrode fixed time was also extended. This microelectrode provided beneficial reference function for the study of the free state of small animals in different brain regions. PMID:27459594

  6. Phonological Processing in Human Auditory Cortical Fields

    PubMed Central

    Woods, David L.; Herron, Timothy J.; Cate, Anthony D.; Kang, Xiaojian; Yund, E. W.

    2011-01-01

    We used population-based cortical-surface analysis of functional magnetic imaging data to characterize the processing of consonant–vowel–consonant syllables (CVCs) and spectrally matched amplitude-modulated noise bursts (AMNBs) in human auditory cortex as subjects attended to auditory or visual stimuli in an intermodal selective attention paradigm. Average auditory cortical field (ACF) locations were defined using tonotopic mapping in a previous study. Activations in auditory cortex were defined by two stimulus-preference gradients: (1) Medial belt ACFs preferred AMNBs and lateral belt and parabelt fields preferred CVCs. This preference extended into core ACFs with medial regions of primary auditory cortex (A1) and the rostral field preferring AMNBs and lateral regions preferring CVCs. (2) Anterior ACFs showed smaller activations but more clearly defined stimulus preferences than did posterior ACFs. Stimulus preference gradients were unaffected by auditory attention suggesting that ACF preferences reflect the automatic processing of different spectrotemporal sound features. PMID:21541252

  7. An improved filtration procedure for measuring opiate receptors in small regions of rat brain.

    PubMed

    Bardo, M T; Bhatnagar, R K; Gebhart, G F

    1982-12-01

    A modified filtration method for in vitro receptor binding was used to determine specific binding of [3H]naloxone to small regions of adult rat brain. Reliable determinations of ligand binding were quantified with about 50 micrograms of protein per assay tube. Large differences in [3H]naloxone binding were obtained between various brain nuclei, and these differences were consistent with prior determinations of opiate receptor densities in various rat brain nuclei using autoradiographic techniques. PMID:6292368

  8. In Alzheimer's disease, hypometabolism in low-amyloid brain regions may be a functional consequence of pathologies in connected brain regions.

    PubMed

    Klupp, Elisabeth; Förster, Stefan; Grimmer, Timo; Tahmasian, Masoud; Yakushev, Igor; Sorg, Christian; Yousefi, Behrooz H; Drzezga, Alexander

    2014-06-01

    In patients with Alzheimer's disease (AD), prominent hypometabolism has been observed in brain regions with minor amyloid load. These hypometabolism-only (HO) areas cannot be explained merely as a consequence of local amyloid toxicity. The aim of this multimodal imaging study was to explore whether such HO phenomenon may be related to pathologies in functionally connected, remote brain regions. Nineteen AD patients and 15 matched controls underwent examinations with [(11)C]PiB-PET and [(18)F]FDG-PET. Voxel-based statistical group comparisons were performed to obtain maps of significantly elevated amyloid burden and reduced cerebral glucose metabolism, respectively, in patients. An HO area was identified by subtraction of equally thresholded result maps (hypometabolism minus amyloid burden). To identify the network typically functionally connected to this HO area, it was used as a seed region for a functional connectivity analysis in resting-state functional magnetic resonance imaging data of 17 elderly healthy controls. The resulting intrinsic connectivity network (HO-ICN) was retransferred into the brains of AD patients to be able to analyze pathologies within this network in the positron emission tomography (PET) datasets. The most prominent HO area was detected in the left middle frontal gyrus of AD patients. The HO-ICN in healthy controls showed a major overlap with brain areas significantly affected by both amyloid deposition and hypometabolism in patients. This association was substantiated by the results of region-of-interest-based and voxel-wise correlation analyses, which revealed strong correlations between the degree of hypometabolism within the HO region and within the HO-ICN. These results support the notion that hypometabolism in brain regions not strongly affected by locoregional amyloid pathology may be related to ongoing pathologies in remote but functionally connected regions, that is, by reduced neuronal input from these regions. PMID:24870443

  9. Sex-specific, rapid neuroestrogen fluctuations and neurophysiological actions in the songbird auditory forebrain

    PubMed Central

    Dong, S. M.; Chao, A.; Schlinger, B. A.

    2012-01-01

    Recent evidence shows that brain-derived steroids such as estrogens (“neuroestrogens”) are controlled in a manner very similar to traditional neurotransmitters. The advent of in vivo microdialysis for steroids in songbirds has provided new information about the spatial and temporal dynamics of neuroestrogen changes in a region of the auditory cortex, the caudomedial nidopallium (NCM). Here, experiments using in vivo microdialysis demonstrate that neuroestradiol (E2) fluctuations occur within the auditory NCM during presentation of naturalistic auditory and visual stimuli in males but only to the presentation of auditory stimuli in females. These changes are acute (within 30 min) and appear to be specific to the NCM, because similar treatments elicit no changes in E2 in a nearby mesopallial region or in circulating plasma. Further experiments coupling in vivo steroid microdialysis with extracellular recordings in NCM show that neuroestrogens rapidly boost auditory responses to song stimuli in females, similar to recent observations in males. We also find that the rapid actions of estradiol on auditory responses are fully mimicked by the cell membrane-impermeable estrogen biotinylestradiol, consistent with acute estrogen actions at the neuronal membrane. Thus we conclude that local and acute E2 flux is regulated by convergent multimodal sensory input, and that this regulation appears to be sex-specific. Second, rapid changes in local E2 levels in NCM have consequences for the modulation of auditory processing in females and males. Finally, the rapid actions of neuroestrogens on NCM auditory processing appear to be mediated by a nonclassical, membrane-bound estrogen receptor. PMID:22190616

  10. Age- and brain region-specific differences in mitochondrial bioenergetics in Brown Norway rats.

    PubMed

    Pandya, Jignesh D; Royland, Joyce E; MacPhail, Robert C; Sullivan, Patrick G; Kodavanti, Prasada Rao S

    2016-06-01

    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 bioenergetic parameters in 5 brain regions (brain stem [BS], frontal cortex, cerebellum, striatum, hippocampus [HIP]) of 4 diverse age groups (1 month [young], 4 months [adult], 12 months [middle-aged], 24 months [old age]) to understand age-related differences in selected brain regions and their possible contribution to age-related chemical sensitivity. Mitochondrial bioenergetic parameters and enzyme activities were measured under identical conditions across multiple age groups and brain regions in Brown Norway rats (n = 5/group). The results indicate age- and brain region-specific patterns in mitochondrial functional endpoints. For example, an age-specific decline in ATP synthesis (State III respiration) was observed in BS and HIP. Similarly, the maximal respiratory capacities (State V1 and V2) showed age-specific declines in all brain regions examined (young > adult > middle-aged > old age). Amongst all regions, HIP had the greatest change in mitochondrial bioenergetics, showing declines in the 4, 12, and 24-months age groups. Activities of mitochondrial pyruvate dehydrogenase complex and electron transport chain complexes I, II, and IV enzymes were also age and brain region specific. In general, changes associated with age were more pronounced with enzyme activities declining as the animals aged (young > adult > middle-aged > old age). These age- and brain region-specific observations may aid in evaluating brain bioenergetic impact on the age-related susceptibility to environmental chemical stressors. PMID:27143418

  11. Studies on Auditory and Vestibular End Organs and Brain Stem Nuclei. [inner ear damage and hearing defects

    NASA Technical Reports Server (NTRS)

    Ades, H. W.

    1974-01-01

    Cats were exposed to tones of 125, 1000, 2000, and 4000 Hz at sound pressure levels in the range 120 to 157.5 db, and for durations of one hour (1000, 2000, 4000 Hz) or four hours (125 Hz). Pure tone audiograms were obtained for each animal before and after exposure. Cochleas of animals were examined by phase-contrast microscopy. Extent of inner ear damage and range of frequencies for which hearing loss occurred increased as exposure tone was decreased in frequency. For example, exposure to 4000 Hz produced damage in a restricted region of the cochlea and hearing loss for a relatively narrow range of frequencies; exposure to 125 Hz produced wide-spread inner ear damage and hearing loss throughout the frequency range 125 to 6000 Hz.

  12. A synaptic and circuit basis for corollary discharge in the auditory cortex

    PubMed Central

    Schneider, David M.; Nelson, Anders; Mooney, Richard

    2014-01-01

    Sensory regions of the brain integrate environmental cues with copies of motor-related signals important for imminent and ongoing movements. In mammals, signals propagating from the motor cortex to the auditory cortex are thought to play a critical role in normal hearing and behavior, yet the synaptic and circuit mechanisms by which these motor-related signals influence auditory cortical activity remain poorly understood. Using in vivo intracellular recordings in behaving mice, we find that excitatory neurons in the auditory cortex are suppressed prior to and during movement, due in part to increased activity of local parvalbumin-positive (PV+) interneurons. Electrophysiology and optogenetic gain- and loss-of-function experiments reveal that motor-related changes in auditory cortical dynamics are driven by a subset of neurons in the secondary motor cortex that innervate the auditory cortex and are active during movement. These findings provide a synaptic and circuit basis for the motor-related corollary discharge hypothesized to facilitate hearing and auditory-guided behaviors. PMID:25162524

  13. Eye Movements during Auditory Attention Predict Individual Differences in Dorsal Attention Network Activity

    PubMed Central

    Braga, Rodrigo M.; Fu, Richard Z.; Seemungal, Barry M.; Wise, Richard J. S.; Leech, Robert

    2016-01-01

    The neural mechanisms supporting auditory attention are not fully understood. A dorsal frontoparietal network of brain regions is thought to mediate the spatial orienting of attention across all sensory modalities. Key parts of this network, the frontal eye fields (FEF) and the superior parietal lobes (SPL), contain retinotopic maps and elicit saccades when stimulated. This suggests that their recruitment during auditory attention might reflect crossmodal oculomotor processes; however this has not been confirmed experimentally. Here we investigate whether task-evoked eye movements during an auditory task can predict the magnitude of activity within the dorsal frontoparietal network. A spatial and non-spatial listening task was used with on-line eye-tracking and functional magnetic resonance imaging (fMRI). No visual stimuli or cues were used. The auditory task elicited systematic eye movements, with saccade rate and gaze position predicting attentional engagement and the cued sound location, respectively. Activity associated with these separate aspects of evoked eye-movements dissociated between the SPL and FEF. However these observed eye movements could not account for all the activation in the frontoparietal network. Our results suggest that the recruitment of the SPL and FEF during attentive listening reflects, at least partly, overt crossmodal oculomotor processes during non-visual attention. Further work is needed to establish whether the network’s remaining contribution to auditory attention is through covert crossmodal processes, or is directly involved in the manipulation of auditory information. PMID:27242465

  14. Differential auditory signal processing in an animal model

    NASA Astrophysics Data System (ADS)

    Lim, Dukhwan; Kim, Chongsun; Chang, Sun O.

    2002-05-01

    Auditory evoked responses were collected in male zebra finches (Poephila guttata) to objectively determine differential frequency selectivity. First, the mating call of the animal was recorded and analyzed for its frequency components through the customized program. Then, auditory brainstem responses and cortical responses of each anesthetized animal were routinely recorded in response to tone bursts of 1-8 kHz derived from the corresponding mating call spectrum. From the results, most mating calls showed relatively consistent spectral structures. The upper limit of the spectrum was well under 10 kHz. The peak energy bands were concentrated in the region less than 5 kHz. The assessment of auditory brainstem responses and cortical evoked potentials showed differential selectivity with a series of characteristic scales. This system appears to be an excellent model to investigate complex sound processing and related language behaviors. These data could also be used in designing effective signal processing strategies in auditory rehabilitation devices such as hearing aids and cochlear implants. [Work supported by Brain Science & Engineering Program from Korean Ministry of Science and Technology.

  15. Neural Representations Used by Brain Regions Underlying Speech Production

    ERIC Educational Resources Information Center

    Segawa, Jennifer Anne

    2013-01-01

    Speech utterances are phoneme sequences but may not always be represented as such in the brain. For instance, electropalatography evidence indicates that as speaking rate increases, gestures within syllables are manipulated separately but those within consonant clusters act as one motor unit. Moreover, speech error data suggest that a syllable's…

  16. Bilateral Brain Regions Associated with Naming in Older Adults

    ERIC Educational Resources Information Center

    Obler, Loraine K.; Rykhlevskaia, Elena; Schnyer, David; Clark-Cotton, Manuella R.; Spiro, Avron, III; Hyun, JungMoon; Kim, Dae-Shik; Goral, Mira; Albert, Martin L.

    2010-01-01

    To determine structural brain correlates of naming abilities in older adults, we tested 24 individuals aged 56-79 on two confrontation-naming tests (the Boston Naming Test (BNT) and the Action Naming Test (ANT)), then collected from these individuals structural Magnetic-Resonance Imaging (MRI) and Diffusion Tensor Imaging (DTI) data. Overall,…

  17. Using PET H2O15 brain imaging to study the functional-anatomical correlates of non-human primate communication.

    PubMed

    Gil-da-Costa, Ricardo; Braun, Allen; Martin, Alex

    2006-03-01

    In this article, we describe methods for using oxygen-15 water (H2O15) positron emission tomography (PET) to explore the functional neuroanatomy of cognition in awake, non-human primates. The discussion is based on a recent study designed to identify regions in the monkey brain associated with perceiving auditory stimuli, and species-specific calls, in particular [Gil-da-Costa et al., Proc. Natl. Acad. Sci. USA 101 (2004) 17516-17521]. Details are provided concerning critical aspects of the experimental paradigm, including pre-scanning habituation sessions to acclimate the animals to the PET scanner environment, and details of a pilot study to determine the auditory stimulus parameters necessary to produce robust activity in brain regions known to process auditory information (belt and parabelt regions of monkey auditory cortex). Methods for acquiring and analyzing PET data to identify significant regions of brain activity in single animals are also presented. PMID:16466931

  18. Better Glasgow outcome score, cerebral perfusion pressure and focal brain oxygenation in severely traumatized brain following direct regional brain hypothermia therapy: A prospective randomized study

    PubMed Central

    Idris, Zamzuri; Zenian, Mohd Sofan; Muzaimi, Mustapha; Hamid, Wan Zuraida Wan Abdul

    2014-01-01

    Background: Induced hypothermia for treatment of traumatic brain injury is controversial. Since many pathways involved in the pathophysiology of secondary brain injury are temperature dependent, regional brain hypothermia is thought capable to mitigate those processes. The objectives of this study are to assess the therapeutic effects and complications of regional brain cooling in severe head injury with Glasgow coma scale (GCS) 6-7. Materials and Methods: A prospective randomized controlled pilot study involving patients with severe traumatic brain injury with GCS 6 and 7 who required decompressive craniectomy. Patients were randomized into two groups: Cooling and no cooling. For the cooling group, analysis was made by dividing the group into mild and deep cooling. Brain was cooled by irrigating the brain continuously with cold Hartmann solution for 24-48 h. Main outcome assessments were a dichotomized Glasgow outcome score (GOS) at 6 months posttrauma. Results: A total of 32 patients were recruited. The cooling-treated patients did better than no cooling. There were 63.2% of patients in cooling group attained good GOS at 6 months compared to only 15.4% in noncooling group (P = 0.007). Interestingly, the analysis at 6 months post-trauma disclosed mild-cooling-treated patients did better than no cooling (70% vs. 15.4% attained good GOS, P = 0.013) and apparently, the deep-cooling-treated patients failed to be better than either no cooling (P = 0.074) or mild cooling group (P = 0.650). Conclusion: Data from this pilot study imply direct regional brain hypothermia appears safe, feasible and maybe beneficial in treating severely head-injured patients. PMID:25685201

  19. Atypical brain lateralisation in the auditory cortex and language performance in 3- to 7-year-old children with high-functioning autism spectrum disorder: a child-customised magnetoencephalography (MEG) study

    PubMed Central

    2013-01-01

    chronological age was a significant predictor of shorter P50m latency in the right hemisphere. Conclusions Using a child-customised MEG device, we studied the P50m component that was evoked through binaural human voice stimuli in young ASD and TD children to examine differences in auditory cortex function that are associated with language development. Our results suggest that there is atypical brain function in the auditory cortex in young children with ASD, regardless of language development. PMID:24103585

  20. Multivoxel patterns reveal functionally differentiated networks underlying auditory feedback processing of speech.

    PubMed

    Zheng, Zane Z; Vicente-Grabovetsky, Alejandro; MacDonald, Ewen N; Munhall, Kevin G; Cusack, Rhodri; Johnsrude, Ingrid S

    2013-03-01

    The everyday act of speaking involves the complex processes of speech motor control. An important component of control is monitoring, detection, and processing of errors when auditory feedback does not correspond to the intended motor gesture. Here we show, using fMRI and converging operations within a multivoxel pattern analysis framework, that this sensorimotor process is supported by functionally differentiated brain networks. During scanning, a real-time speech-tracking system was used to deliver two acoustically different types of distorted auditory feedback or unaltered feedback while human participants were vocalizing monosyllabic words, and to present the same auditory stimuli while participants were passively listening. Whole-brain analysis of neural-pattern similarity revealed three functional networks that were differentially sensitive to distorted auditory feedback during vocalization, compared with during passive listening. One network of regions appears to encode an "error signal" regardless of acoustic features of the error: this network, including right angular gyrus, right supplementary motor area, and bilateral cerebellum, yielded consistent neural patterns across acoustically different, distorted feedback types, only during articulation (not during passive listening). In contrast, a frontotemporal network appears sensitive to the speech features of auditory stimuli during passive listening; this preference for speech features was diminished when the same stimuli were presented as auditory concomitants of vocalization. A third network, showing a distinct functional pattern from the other two, appears to capture aspects of both neural response profiles. Together, our findings suggest that auditory feedback processing during speech motor control may rely on multiple, interactive, functionally differentiated neural systems. PMID:23467350

  1. Some specifics on the brain drain from the Andean region.

    PubMed

    Mckee, D L

    1983-01-01

    An analysis of the brain drain from the Andean countries of Bolivia, Chile, Colombia, Ecuador, and Peru to the United States is presented. The data are from a survey of 62 persons from those countries who are currently residing in the United States and are listed in the current edition of "American Men and Women of Science". The reasons why they left their country of origin and are staying in the United States are considered. (summary in FRE, SPA) PMID:12159629

  2. Regional and cellular expression of CYP2D6 in human brain: higher levels in alcoholics.

    PubMed

    Miksys, Sharon; Rao, Yushu; Hoffmann, Ewa; Mash, Deborah C; Tyndale, Rachel F

    2002-09-01

    Cytochrome P450 (CYP) 2D6 is expressed in liver, brain and other extrahepatic tissues where it metabolizes a range of centrally acting drugs and toxins. As ethanol can induce CYP2D in rat brain, we hypothesized that CYP2D6 expression is higher in brains of human alcoholics. We examined regional and cellular expression of CYP2D6 mRNA and protein by RT-PCR, Southern blotting, slot blotting, immunoblotting and immunocytochemistry. A significant correlation was found between mean mRNA and CYP2D6 protein levels across 13 brain regions. Higher expression was detected in 13 brain regions of alcoholics (n = 8) compared to nonalcoholics (n = 5) (anovap < 0.0001). In hippocampus this was localized in CA1-3 pyramidal cells and dentate gyrus granular neurons. In cerebellum this was localized in Purkinje cells and their dendrites. Both of these brain regions, and these same cell-types, are known to be susceptible to alcohol damage. For one case, a poor metabolizer (CYP2D6*4/*4), there was no detectable CYP2D6 protein, confirming the specificity of the antibody used. These data suggest that in alcoholics elevated brain CYP2D6 expression may contribute to altered sensitivity to centrally acting drugs and to the mediation of neurotoxic and behavioral effects of alcohol. PMID:12354285

  3. Global differential expression of genes located in the Down Syndrome Critical Region in normal human brain

    PubMed Central

    Montoya, Julio Cesar; Fajardo, Dianora; Peña, Angela; Sánchez, Adalberto; Domínguez, Martha C; Satizábal, José María

    2014-01-01

    Background: The information of gene expression obtained from databases, have made possible the extraction and analysis of data related with several molecular processes involving not only in brain homeostasis but its disruption in some neuropathologies; principally in Down syndrome and the Alzheimer disease. Objective: To correlate the levels of transcription of 19 genes located in the Down Syndrome Critical Region (DSCR) with their expression in several substructures of normal human brain. Methods: There were obtained expression profiles of 19 DSCR genes in 42 brain substructures, from gene expression values available at the database of the human brain of the Brain Atlas of the Allen Institute for Brain Sciences", (http://human.brain-map.org/). The co-expression patterns of DSCR genes in brain were calculated by using multivariate statistical methods. Results: Highest levels of gene expression were registered at caudate nucleus, nucleus accumbens and putamen among central areas of cerebral cortex. Increased expression levels of RCAN1 that encode by a protein involved in signal transduction process of the CNS were recorded for PCP4 that participates in the binding to calmodulin and TTC3; a protein that is associated with differentiation of neurons. That previously identified brain structures play a crucial role in the learning process, in different class of memory and in motor skills. Conclusion: The precise regulation of DSCR gene expression is crucial to maintain the brain homeostasis, especially in those areas with high levels of gene expression associated with a remarkable process of learning and cognition. PMID:25767303

  4. Physiologically based pharmacokinetic modeling to investigate regional brain distribution kinetics in rats.

    PubMed

    Westerhout, Joost; Ploeger, Bart; Smeets, Jean; Danhof, Meindert; de Lange, Elizabeth C M

    2012-09-01

    One of the major challenges in the development of central nervous system (CNS)-targeted drugs is predicting CNS exposure in human from preclinical data. In this study, we present a methodology to investigate brain disposition in rats using a physiologically based modeling approach aiming at improving the prediction of human brain exposure. We specifically focused on quantifying regional diffusion and fluid flow processes within the brain. Acetaminophen was used as a test compound as it is not subjected to active transport processes. Microdialysis probes were implanted in striatum, for sampling brain extracellular fluid (ECF) concentrations, and in lateral ventricle (LV) and cisterna magna (CM), for sampling cerebrospinal fluid (CSF) concentrations. Serial blood samples were taken in parallel. These data, in addition to physiological parameters from literature, were used to develop a physiologically based model to describe the regional brain pharmacokinetics of acetaminophen. The concentration-time profiles of brain ECF, CSF(LV), and CSF(CM) indicate a rapid equilibrium with plasma. However, brain ECF concentrations are on average fourfold higher than CSF concentrations, with average brain-to-plasma AUC(0-240) ratios of 121%, 28%, and 35% for brain ECF, CSF(LV), and CSF(CM), respectively. It is concluded that for acetaminophen, a model compound for passive transport into, within, and out of the brain, differences exist between the brain ECF and the CSF pharmacokinetics. The physiologically based pharmacokinetic modeling approach is important, as it allowed the prediction of human brain ECF exposure on the basis of human CSF concentrations. PMID:22588644

  5. Developmental Trajectories of Auditory Cortex Synaptic Structures and Gap-Prepulse Inhibition of Acoustic Startle Between Early Adolescence and Young Adulthood in Mice.

    PubMed

    Moyer, Caitlin E; Erickson, Susan L; Fish, Kenneth N; Thiels, Edda; Penzes, Peter; Sweet, Robert A

    2016-05-01

    Cortical excitatory and inhibitory synapses are disrupted in schizophrenia, the symptoms of which often emerge during adolescence, when cortical excitatory synapses undergo pruning. In auditory cortex, a brain region implicated in schizophrenia, little is known about the development of excitatory and inhibitory synapses between early adolescence and young adulthood, and how these changes impact auditory cortex function. We used immunohistochemistry and quantitative fluorescence microscopy to quantify dendritic spines and GAD65-expressing inhibitory boutons in auditory cortex of early adolescent, late adolescent, and young adult mice. Numbers of spines decreased between early adolescence and young adulthood, during which time responses increased in an auditory cortex-dependent sensory task, silent gap-prepulse inhibition of the acoustic startle reflex (gap-PPI). Within-bouton GAD65 protein and GAD65-expressing bouton numbers decreased between late adolescence and young adulthood, a delay in onset relative to spine and gap-PPI changes. In mice lacking the spine protein kalirin, there were no significant changes in spine number, within-bouton GAD65 protein, or gap-PPI between adolescence and young adulthood. These results illustrate developmental changes in auditory cortex spines, inhibitory boutons, and auditory cortex function between adolescence and young adulthood, and provide insights into how disrupted adolescent neurodevelopment could contribute to auditory cortex synapse pathology and auditory impairments. PMID:25759333

  6. Polarity-specific transcranial direct current stimulation disrupts auditory pitch learning

    PubMed Central

    Matsushita, Reiko; Andoh, Jamila; Zatorre, Robert J.

    2015-01-01

    Transcranial direct current stimulation (tDCS) is attracting increasing interest because of its potential for therapeutic use. While its effects have been investigated mainly with motor and visual tasks, less is known in the auditory domain. Past tDCS studies with auditory tasks demonstrated various behavioral outcomes, possibly due to differences in stimulation parameters, task-induced brain activity, or task measurements used in each study. Further research, using well-validated tasks is therefore required for clarification of behavioral effects of tDCS on the auditory system. Here, we took advantage of findings from a prior functional magnetic resonance imaging study, which demonstrated that the right auditory cortex is modulated during fine-grained pitch learning of microtonal melodic patterns. Targeting the right auditory cortex with tDCS using this same task thus allowed us to test the hypothesis that this region is causally involved in pitch learning. Participants in the current study were trained for 3 days while we measured pitch discrimination thresholds using microtonal melodies on each day using a psychophysical staircase procedure. We administered anodal, cathodal, or sham tDCS to three groups of participants over the right auditory cortex on the second day of training during performance of the task. Both the sham and the cathodal groups showed the expected significant learning effect (decreased pitch threshold) over the 3 days of training; in contrast we observed a blocking effect of anodal tDCS on auditory pitch learning, such that this group showed no significant change in thresholds over the 3 days. The results support a causal role for the right auditory cortex in pitch discrimination learning. PMID:26041982

  7. Polarity-specific transcranial direct current stimulation disrupts auditory pitch learning.

    PubMed

    Matsushita, Reiko; Andoh, Jamila; Zatorre, Robert J

    2015-01-01

    Transcranial direct current stimulation (tDCS) is attracting increasing interest because of its potential for therapeutic use. While its effects have been investigated mainly with motor and visual tasks, less is known in the auditory domain. Past tDCS studies with auditory tasks demonstrated various behavioral outcomes, possibly due to differences in stimulation parameters, task-induced brain activity, or task measurements used in each study. Further research, using well-validated tasks is therefore required for clarification of behavioral effects of tDCS on the auditory system. Here, we took advantage of findings from a prior functional magnetic resonance imaging study, which demonstrated that the right auditory cortex is modulated during fine-grained pitch learning of microtonal melodic patterns. Targeting the right auditory cortex with tDCS using this same task thus allowed us to test the hypothesis that this region is causally involved in pitch learning. Participants in the current study were trained for 3 days while we measured pitch discrimination thresholds using microtonal melodies on each day using a psychophysical staircase procedure. We administered anodal, cathodal, or sham tDCS to three groups of participants over the right auditory cortex on the second day of training during performance of the task. Both the sham and the cathodal groups showed the expected significant learning effect (decreased pitch threshold) over the 3 days of training; in contrast we observed a blocking effect of anodal tDCS on auditory pitch learning, such that this group showed no significant change in thresholds over the 3 days. The results support a causal role for the right auditory cortex in pitch discrimination learning. PMID:26041982

  8. Stars from the darkest night: unlocking the neurogenic potential of astrocytes in different brain regions.

    PubMed

    Magnusson, Jens P; Frisén, Jonas

    2016-04-01

    In a few regions of the adult brain, specialized astrocytes act as neural stem cells capable of sustaining life-long neurogenesis. In other, typically non-neurogenic regions, some astrocytes have an intrinsic capacity to produce neurons when provoked by particular conditions but do not use this ability to replace neurons completely after injury or disease. Why do astrocytes display regional differences and why do they not use their neurogenic capacity for brain repair to a greater extent? In this Review, we discuss the neurogenic potential of astrocytes in different brain regions and ask what stimulates this potential in some regions but not in others. We discuss the transcriptional networks and environmental cues that govern cell identity, and consider how the activation of neurogenic properties in astrocytes can be understood as the de-repression of a latent neurogenic transcriptional program. PMID:27048686

  9. Mapping brain region activity during chewing: a functional magnetic resonance imaging study.

    PubMed

    Onozuka, M; Fujita, M; Watanabe, K; Hirano, Y; Niwa, M; Nishiyama, K; Saito, S

    2002-11-01

    Mastication has been suggested to increase neuronal activities in various regions of the human brain. However, because of technical difficulties, the fine anatomical and physiological regions linked to mastication have not been fully elucidated. Using functional magnetic resonance imaging during cycles of rhythmic gum-chewing and no chewing, we therefore examined the interaction between chewing and brain regional activity in 17 subjects (aged 20-31 years). In all subjects, chewing resulted in a bilateral increase in blood oxygenation level-dependent (BOLD) signals in the sensorimotor cortex, supplementary motor area, insula, thalamus, and cerebellum. In addition, in the first three regions, chewing of moderately hard gum produced stronger BOLD signals than the chewing of hard gum. However, the signal was higher in the cerebellum and not significant in the thalamus, respectively. These results suggest that chewing causes regional increases in brain neuronal activities which are related to biting force. PMID:12407087

  10. The Construction of Common and Specific Significance Subnetworks of Alzheimer's Disease from Multiple Brain Regions

    PubMed Central

    Mou, Xiaoyang; Zhang, Na; Zeng, Weiming; Li, Shasha; Yang, Yang

    2015-01-01

    Alzheimer's disease (AD) is a progressively and fatally neurodegenerative disorder and leads to irreversibly cognitive and memorial damage in different brain regions. The identification and analysis of the dysregulated pathways and subnetworks among affected brain regions will provide deep insights for the pathogenetic mechanism of AD. In this paper, commonly and specifically significant subnetworks were identified from six AD brain regions. Protein-protein interaction (PPI) data were integrated to add molecular biological information to construct the functional modules of six AD brain regions by Heinz algorithm. Then, the simulated annealing algorithm based on edge weight is applied to predicting and optimizing the maximal scoring networks for common and specific genes, respectively, which can remove the weak interactions and add the prediction of strong interactions to increase the accuracy of the networks. The identified common subnetworks showed that inflammation of the brain nerves is one of the critical factors of AD and calcium imbalance may be a link among several causative factors in AD pathogenesis. In addition, the extracted specific subnetworks for each brain region revealed many biologically functional mechanisms to understand AD pathogenesis. PMID:25866779

  11. Permittivity coupling across brain regions determines seizure recruitment in partial epilepsy.

    PubMed

    Proix, Timothée; Bartolomei, Fabrice; Chauvel, Patrick; Bernard, Christophe; Jirsa, Viktor K

    2014-11-01

    Brain regions generating seizures in patients with refractory partial epilepsy are referred to as the epileptogenic zone (EZ). During a seizure, paroxysmal activity is not restricted to the EZ, but may recruit other brain regions and propagate activity through large brain networks, which comprise brain regions that are not necessarily epileptogenic. The identification of the EZ is crucial for candidates for neurosurgery and requires unambiguous criteria that evaluate the degree of epileptogenicity of brain regions. To obtain such criteria and investigate the mechanisms of seizure recruitment and propagation, we develop a mathematical framework of coupled neural populations, which can interact via signaling through a slow permittivity variable. The permittivity variable captures effects evolving on slow timescales, including extracellular ionic concentrations and energy metabolism, with time delays of up to seconds as observed clinically. Our analyses provide a set of indices quantifying the degree of epileptogenicity and predict conditions, under which seizures propagate to nonepileptogenic brain regions, explaining the responses to intracerebral electric stimulation in epileptogenic and nonepileptogenic areas. In conjunction, our results provide guidance in the presurgical evaluation of epileptogenicity based on electrographic signatures in intracerebral electroencephalograms. PMID:25378166

  12. The construction of common and specific significance subnetworks of Alzheimer's disease from multiple brain regions.

    PubMed

    Kong, Wei; Mou, Xiaoyang; Zhang, Na; Zeng, Weiming; Li, Shasha; Yang, Yang

    2015-01-01

    Alzheimer's disease (AD) is a progressively and fatally neurodegenerative disorder and leads to irreversibly cognitive and memorial damage in different brain regions. The identification and analysis of the dysregulated pathways and subnetworks among affected brain regions will provide deep insights for the pathogenetic mechanism of AD. In this paper, commonly and specifically significant subnetworks were identified from six AD brain regions. Protein-protein interaction (PPI) data were integrated to add molecular biological information to construct the functional modules of six AD brain regions by Heinz algorithm. Then, the simulated annealing algorithm based on edge weight is applied to predicting and optimizing the maximal scoring networks for common and specific genes, respectively, which can remove the weak interactions and add the prediction of strong interactions to increase the accuracy of the networks. The identified common subnetworks showed that inflammation of the brain nerves is one of the critical factors of AD and calcium imbalance may be a link among several causative factors in AD pathogenesis. In addition, the extracted specific subnetworks for each brain region revealed many biologically functional mechanisms to understand AD pathogenesis. PMID:25866779

  13. Auditory Efferent System Modulates Mosquito Hearing.

    PubMed

    Andrés, Marta; Seifert, Marvin; Spalthoff, Christian; Warren, Ben; Weiss, Lukas; Giraldo, Diego; Winkler, Margret; Pauls, Stephanie; Göpfert, Martin C

    2016-08-01

    The performance of vertebrate ears is controlled by auditory efferents that originate in the brain and innervate the ear, synapsing onto hair cell somata and auditory afferent fibers [1-3]. Efferent activity can provide protection from noise and facilitate the detection and discrimination of sound by modulating mechanical amplification by hair cells and transmitter release as well as auditory afferent action potential firing [1-3]. Insect auditory organs are thought to lack efferent control [4-7], but when we inspected mosquito ears, we obtained evidence for its existence. Antibodies against synaptic proteins recognized rows of bouton-like puncta running along the dendrites and axons of mosquito auditory sensory neurons. Electron microscopy identified synaptic and non-synaptic sites of vesicle release, and some of the innervating fibers co-labeled with somata in the CNS. Octopamine, GABA, and serotonin were identified as efferent neurotransmitters or neuromodulators that affect auditory frequency tuning, mechanical amplification, and sound-evoked potentials. Mosquito brains thus modulate mosquito ears, extending the use of auditory efferent systems from vertebrates to invertebrates and adding new levels of complexity to mosquito sound detection and communication. PMID:27476597

  14. Frequency band-importance functions for auditory and auditory-visual speech recognition

    NASA Astrophysics Data System (ADS)

    Grant, Ken W.

    2005-04-01

    In many everyday listening environments, speech communication involves the integration of both acoustic and visual speech cues. This is especially true in noisy and reverberant environments where the speech signal is highly degraded, or when the listener has a hearing impairment. Understanding the mechanisms involved in auditory-visual integration is a primary interest of this work. Of particular interest is whether listeners are able to allocate their attention to various frequency regions of the speech signal differently under auditory-visual conditions and auditory-alone conditions. For auditory speech recognition, the most important frequency regions tend to be around 1500-3000 Hz, corresponding roughly to important acoustic cues for place of articulation. The purpose of this study is to determine the most important frequency region under auditory-visual speech conditions. Frequency band-importance functions for auditory and auditory-visual conditions were obtained by having subjects identify speech tokens under conditions where the speech-to-noise ratio of different parts of the speech spectrum is independently and randomly varied on every trial. Point biserial correlations were computed for each separate spectral region and the normalized correlations are interpreted as weights indicating the importance of each region. Relations among frequency-importance functions for auditory and auditory-visual conditions will be discussed.

  15. Auditory Learning Materials for Special Education: Catalog.

    ERIC Educational Resources Information Center

    Smith, Marsha C.; O'Connor, Phyllis

    The catalog (developed by the Great Lakes Region Special Education Instructional Materials Center) provides information on more than 100 auditory learning materials for use in special education. Described in the first section of the catalog are procedures used to evaluate and classify auditory instructional materials, including a list of…

  16. Regional Distribution of Copper, Zinc and Iron in Brain of Wistar Rat Model for Non-Wilsonian Brain Copper Toxicosis.

    PubMed

    Pal, Amit; Prasad, Rajendra

    2016-03-01

    In previous studies, we have reported first in vivo evidence of copper deposition in the choroid plexus, cognitive impairments, astrocytes swelling (Alzheimer type II cells) and astrogliosis (increase in number of astrocytes), and degenerated neurons coupled with significant increase in the hippocampus copper and zinc content in copper-intoxicated Wistar rats. Nonetheless, hippocampus iron levels were not affected by chronic copper-intoxication. Notwithstanding information on distribution of copper, zinc and iron status in different regions of brain due to chronic copper exposure remains fragmentary. In continuation with our previous study, the aim of this study was to investigate the effects of intraperitoneally injected copper lactate (0.15 mg Cu/100 g body weight) daily for 90 days on copper, zinc and iron levels in different regions of the brain using atomic absorption spectrophotometry. Copper-intoxicated group showed significantly increased cortex, cerebellum and striatum copper content (76, 46.8 and 80.7 % increase, respectively) compared to control group. However, non-significant changes were observed for the zinc and iron content in cortex, cerebellum and striatum due to chronic copper exposure. In conclusion, the current study demonstrates that chronic copper toxicity causes differential copper buildup in cortex, cerebellum and striatum region of central nervous system of male Wistar rats; signifying the critical requirement to discretely evaluate the effect of copper neurotoxicity in different brain regions, and ensuing neuropathological and cognitive dysfunctions. PMID:26855494

  17. An integrative analysis of regional gene expression profiles in the human brain.

    PubMed

    Myers, Emma M; Bartlett, Christopher W; Machiraju, Raghu; Bohland, Jason W

    2015-02-01

    Studies of the brain's transcriptome have become prominent in recent years, resulting in an accumulation of datasets with somewhat distinct attributes. These datasets, which are often analyzed only in isolation, also are often collected with divergent goals, which are reflected in their sampling properties. While many researchers have been interested in sampling gene expression in one or a few brain areas in a large number of subjects, recent efforts from the Allen Institute for Brain Sciences and others have focused instead on dense neuroanatomical sampling, necessarily limiting the number of individual donor brains studied. The purpose of the present work is to develop methods that draw on the complementary strengths of these two types of datasets for study of the human brain, and to characterize the anatomical specificity of gene expression profiles and gene co-expression networks derived from human brains using different specific technologies. The approach is applied using two publicly accessible datasets: (1) the high anatomical resolution Allen Human Brain Atlas (AHBA, Hawrylycz et al., 2012) and (2) a relatively large sample size, but comparatively coarse neuroanatomical dataset described previously by Gibbs et al. (2010). We found a relatively high degree of correspondence in differentially expressed genes and regional gene expression profiles across the two datasets. Gene co-expression networks defined in individual brain regions were less congruent, but also showed modest anatomical specificity. Using gene modules derived from the Gibbs dataset and from curated gene lists, we demonstrated varying degrees of anatomical specificity based on two classes of methods, one focused on network modularity and the other focused on enrichment of expression levels. Two approaches to assessing the statistical significance of a gene set's modularity in a given brain region were studied, which provide complementary information about the anatomical specificity of a gene

  18. Longitudinal regional brain volume loss in schizophrenia: Relationship to antipsychotic medication and change in social function

    PubMed Central

    Guo, Joyce Y.; Huhtaniska, Sanna; Miettunen, Jouko; Jääskeläinen, Erika; Kiviniemi, Vesa; Nikkinen, Juha; Moilanen, Jani; Haapea, Marianne; Mäki, Pirjo; Jones, Peter B.; Veijola, Juha; Isohanni, Matti; Murray, Graham K.

    2015-01-01

    Background Progressive brain volume loss in schizophrenia has been reported in previous studies but its cause and regional distribution remains unclear. We investigated progressive regional brain reductions in schizophrenia and correlations with potential mediators. Method Participants were drawn from the Northern Finland Birth Cohort 1966. A total of 33 schizophrenia individuals and 71 controls were MRI scanned at baseline (mean age = 34.7, SD = 0.77) and at follow-up (mean age = 43.4, SD = 0.44). Regional brain change differences and associations with clinical mediators were examined using FSL voxelwise SIENA. Results Schizophrenia cases exhibited greater progressive brain reductions than controls, mainly in the frontal and temporal lobes. The degree of periventricular brain volume reductions were predicted by antipsychotic medication exposure at the fourth ventricular edge and by the number of days in hospital between the scans (a proxy measure of relapse duration) at the thalamic ventricular border. Decline in social and occupational functioning was associated with right supramarginal gyrus reduction. Conclusion Our findings are consistent with the possibility that antipsychotic medication exposure and time spent in relapse partially explain progressive brain reductions in schizophrenia. However, residual confounding could also account for the findings and caution must be applied before drawing causal inferences from associations demonstrated in observational studies of modest size. Less progressive brain volume loss in schizophrenia may indicate better preserved social and occupational functions. PMID:26189075

  19. Regional brain volumes and cognition in childhood epilepsy: Does size really matter?

    PubMed Central

    Zelko, Frank A.; Pardoe, Heath R.; Blackstone, Sarah R.; Jackson, Graeme D.; Berg, Anne T.

    2014-01-01

    Purpose Recent studies have correlated neurocognitive function and regional brain volumes in children with epilepsy. We tested whether brain volume differences between children with and without epilepsy explained differences in neurocognitive function. Methods The study sample included 108 individuals with uncomplicated nonsyndromic epilepsy (NSE) and 36 healthy age- and gender-matched controls. Participants received a standardized cognitive battery. Whole brain T1-weighted MRI was obtained and volumes analyzed with FreeSurfer (TM). Key Findings Total brain volume (TBV) was significantly smaller in cases. After adjustment for TBV, cases had significantly larger regional grey matter volumes for total, frontal, parietal, and precentral cortex. Cases had poorer performance on neurocognitive indices of intelligence and variability of sustained attention. In cases, TBV showed small associations with intellectual indices of verbal and perceptual ability, working memory, and overall IQ. In controls, TBV showed medium associations with working memory and variability of sustained attention. In both groups, small associations were seen between some TBV-adjusted regional brain volumes and neurocognitive indices, but not in a consistent pattern. Brain volume differences did not account for cognitive differences between the groups. Significance Patients with uncomplicated NSE have smaller brains than controls but areas of relative grey matter enlargement. That this relative regional enlargement occurs in the context of poorer overall neurocognitive functioning suggests that it is not adaptive. However, the lack of consistent associations between case-control differences in brain volumes and cognitive functioning suggests that brain volumes have limited explanatory value for cognitive functioning in childhood epilepsy. PMID:24630049

  20. Neuroestrogen signaling in the songbird auditory cortex propagates into a sensorimotor network via an 'interface' nucleus.

    PubMed

    Pawlisch, B A; Remage-Healey, L

    2015-01-22

    Neuromodulators rapidly alter activity of neural circuits and can therefore shape higher order functions, such as sensorimotor integration. Increasing evidence suggests that brain-derived estrogens, such as 17-β-estradiol, can act rapidly to modulate sensory processing. However, less is known about how rapid estrogen signaling can impact downstream circuits. Past studies have demonstrated that estradiol levels increase within the songbird auditory cortex (the caudomedial nidopallium, NCM) during social interactions. Local estradiol signaling enhances the auditory-evoked firing rate of neurons in NCM to a variety of stimuli, while also enhancing the selectivity of auditory-evoked responses of neurons in a downstream sensorimotor brain region, HVC (proper name). Since these two brain regions are not directly connected, we employed dual extracellular recordings in HVC and the upstream nucleus interfacialis of the nidopallium (NIf) during manipulations of estradiol within NCM to better understand the pathway by which estradiol signaling propagates to downstream circuits. NIf has direct input into HVC, passing auditory information into the vocal motor output pathway, and is a possible source of the neural selectivity within HVC. Here, during acute estradiol administration in NCM, NIf neurons showed increases in baseline firing rates and auditory-evoked firing rates to all stimuli. Furthermore, when estradiol synthesis was blocked in NCM, we observed simultaneous decreases in the selectivity of NIf and HVC neurons. These effects were not due to direct estradiol actions because NIf has little to no capability for local estrogen synthesis or estrogen receptors, and these effects were specific to NIf because other neurons immediately surrounding NIf did not show these changes. Our results demonstrate that transsynaptic, rapid fluctuations in neuroestrogens are transmitted into NIf and subsequently HVC, both regions important for sensorimotor integration. Overall, these

  1. Investment in higher order central processing regions is not constrained by brain size in social insects

    PubMed Central

    Muscedere, Mario L.; Gronenberg, Wulfila; Moreau, Corrie S.; Traniello, James F. A.

    2014-01-01

    The extent to which size constrains the evolution of brain organization and the genesis of complex behaviour is a central, unanswered question in evolutionary neuroscience. Advanced cognition has long been linked to the expansion of specific brain compartments, such as the neocortex in vertebrates and the mushroom bodies in insects. Scaling constraints that limit the size of these brain regions in small animals may therefore be particularly significant to behavioural evolution. Recent findings from studies of paper wasps suggest miniaturization constrains the size of central sensory processing brain centres (mushroom body calyces) in favour of peripheral, sensory input centres (antennal and optic lobes). We tested the generality of this hypothesis in diverse eusocial hymenopteran species (ants, bees and wasps) exhibiting striking variation in body size and thus brain size. Combining multiple neuroanatomical datasets from these three taxa, we found no universal size constraint on brain organization within or among species. In fact, small-bodied ants with miniscule brains had mushroom body calyces proportionally as large as or larger than those of wasps and bees with brains orders of magnitude larger. Our comparative analyses suggest that brain organization in ants is shaped more by natural selection imposed by visual demands than intrinsic design limitations. PMID:24741016

  2. Test-retest reproducibility for regional brain metabolic responses to lorazepam

    SciTech Connect

    Wang, G.J.; Volkow, N.D.; Overall, J. |||

    1996-05-01

    Changes in regional brain glucose metabolism as assessed with PET and FDG in response to acute administration of benzodiazepine agonists have been used as indicators of benzodiazepine-GABA receptor function. The purpose of this study was to assess the reproducibility of these responses. Sixteen healthy right-handed men were scanned with positron emission tomography (PET) and [F-18] fluorodeoxyglucose (FDG) twice: prior to placebo and prior to lorazepam (30 {mu}g/kg). The same double FDG procedure was repeated 6-8 weeks later to assess test-retest reproducibility. The regional absolute brain metabolic values obtained during the second evaluation were significantly lower than those obtained for the first evaluation regardless of condition (p {le} 0.001). Lorazepam significantly and consistently decreased whole brain metabolism and the magnitude as well as the regional pattern of the changes was comparable for both studies (12.3 {plus_minus} 6.9% and 13.7 {plus_minus} 7.4%). Lorazepam effects were largest in thalamus (22.2 {plus_minus} 8.9%). Relative metabolic measures ROI/global were highly reproducible both for drug as well as replication condition. This is the first study to measure test-retest reproducibility in regional brain metabolic response to a pharmacological challenge. While the global and regional absolute metabolic values were significantly lower for the repeated evaluation, the regional brain metabolic response to lorazepam was highly reproducible.

  3. Parameters of diffusional kurtosis imaging for the diagnosis of acute cerebral infarction in different brain regions

    PubMed Central

    Guo, Yue-Lin; Li, Su-Juan; Zhang, Zhong-Ping; Shen, Zhi-Wei; Zhang, Gui-Shan; Yan, Gen; Wang, Yan-Ting; Rao, Hai-Bing; Zheng, Wen-Bin; Wu, Ren-Hua

    2016-01-01

    Diffusional kurtosis imaging (DKI) is a new type diffusion-weighted sequence which measures the non-Gaussianity of water diffusion. The present study aimed to investigate whether the parameters of DKI could distinguish between differences in water molecule diffusion in various brain regions under the conditions of acute infarction and to identify the optimal DKI parameter for locating ischemic lesions in each brain region. A total of 28 patients with acute ischemic stroke in different brain regions were recruited for the present study. The relative values of DKI parameters were selected as major assessment indices, and the homogeneity of background image and contrast of adjacent structures were used as minor assessment indices. According to the brain region involved in three DKI parametric maps, including mean kurtosis (MK), axial kurtosis (Ka) and radial kurtosis (Kr), 112 groups of regions of interest were outlined in the following regions: Corpus callosum (n=17); corona radiata (n=26); thalamus (n=21); subcortical white matter (n=24); and cerebral cortex (n=24). For ischemic lesions in the corpus callosum and corona radiata, significant increases in relative Ka were detected, as compared with the other parameters (P<0.05). For ischemic lesions in the thalamus, subcortical white matter and cerebral cortices, an increase in the three parameters was detected, however this difference was not significant. Minor assessment indices demonstrated that Ka lacked tissue contrast and the background of Kr was heterogeneous; thus, MK was the superior assessment parameter for ischemic lesions in these regions. In conclusion, Ka is better suited for the diagnosis of acute ischemic lesions in highly anisotropic brain regions, such as the corpus callosum and corona radiate. MK may be appropriate for the lesions in low anisotropic or isotropic brain regions, such as the thalamus, subcortical white matter and cerebral cortices.

  4. The DNA methylome and transcriptome of different brain regions in schizophrenia and bipolar disorder.

    PubMed

    Xiao, Yun; Camarillo, Cynthia; Ping, Yanyan; Arana, Tania Bedard; Zhao, Hongying; Thompson, Peter M; Xu, Chaohan; Su, Bin Brenda; Fan, Huihui; Ordonez, Javier; Wang, Li; Mao, Chunxiang; Zhang, Yunpeng; Cruz, Dianne; Escamilla, Michael A; Li, Xia; Xu, Chun

    2014-01-01

    Extensive changes in DNA methylation have been observed in schizophrenia (SC) and bipolar disorder (BP), and may contribute to the pathogenesis of these disorders. Here, we performed genome-scale DNA methylation profiling using methylated DNA immunoprecipitation followed by sequencing (MeDIP-seq) on two brain regions (including frontal cortex and anterior cingulate) in 5 SC, 7 BP and 6 normal subjects. Comparing with normal controls, we identified substantial differentially methylated regions (DMRs) in these two brain regions of SC and BP. To our surprise, different brain regions show completely distinct distributions of DMRs across the genomes. In frontal cortex of both SC and BP subjects, we observed widespread hypomethylation as compared to normal controls, preferentially targeting the terminal ends of the chromosomes. In contrast, in anterior cingulate, both SC and BP subjects displayed extensive gain of methylation. Notably, in these two brain regions of SC and BP, only a few DMRs overlapped with promoters, whereas a greater proportion occurs in introns and intergenic regions. Functional enrichment analysis indicated that important psychiatric disorder-related biological processes such as neuron development, differentiation and projection may be altered by epigenetic changes located in the intronic regions. Transcriptome analysis revealed consistent dysfunctional processes with those determined by DMRs. Furthermore, DMRs in the same brain regions from SC and BP could successfully distinguish BP and/or SC from normal controls while differentially expressed genes could not. Overall, our results support a major role for brain-region-dependent aberrant DNA methylation in the pathogenesis of these two disorders. PMID:24776767

  5. Regional brain perfusion in 10 normal dogs measured using Technetium-99m ethyl cysteinate dimer spect.

    PubMed

    Peremans, K; De Bondt, P; Audenaert, K; Van Laere, K; Gielen, I; Koole, M; Versijpt, J; Van Bree, H; Verschooten, F; Dierckx, R

    2001-01-01

    Single photon emission computed tomography (SPECT) of the brain using perfusion tracers allows estimation of regional brain perfusion. This allows in vivo examination of brain function in the setting of neuropsychologic and pathophysiologic changes. However functional imaging data on brain perfusion in dogs are limited. Hence, the aim of this study was to determine the scintigraphic regional perfusion pattern of the normal canine brain. Ten healthy shepherd type dogs were injected with 925 MBq Technetium-99m ethyl cysteinate (ECD) 20 minutes before the examination. Acquisition was performed using a triple head gamma camera equipped with fanbeam collimators. Uniform attenuation correction and triple energy window correction were applied. Computed tomographic images were obtained from the same dogs, reoriented along the orbito-meatal axis and SPECT perfusion data were coregistered to the CT-volume data. Based on morphological and suggested brain divisions, regions-of-interest (ROIs) were defined for the bilateral frontocerebral, temporocerebral, parietocerebral, occipitocerebral, cerebellar, thalamic, and striatal area. Regional count density was normalized on total counts. All dogs had the highest uptake in the thalamic/striatal area compared to a rather homogeneous cerebral uptake. No significant left/right count differences were found, but a rostro-caudal gradient (+12-13%) was present. In this group, age and gender did not influence the perfusion pattern. PMID:11768526

  6. Regional Brain Volumes and ADHD Symptoms in Middle-Aged Adults: The PATH Through Life Study.

    PubMed

    Das, Debjani; Cherbuin, Nicolas; Anstey, Kaarin J; Abhayaratna, Walter; Easteal, Simon

    2014-02-24

    Objective: We investigated whether volumetric differences in ADHD-associated brain regions are related to current symptoms of inattention and hyperactivity in healthy middle-aged adults and whether co-occurring anxiety/depression symptoms moderate these relationships. Method: ADHD Self-Report Scale and Brief Patient Health Questionnaire were used to assess current symptoms of inattention, hyperactivity, anxiety, and depression in a population-based sample (n = 269). Brain volumes, measured using a semi-automated method, were analyzed using multiple regression and structural equation modeling to evaluate brain volume-inattention/hyperactivity symptom relationships for selected regions. Results: Volumes of the left nucleus accumbens and a region overlapping the dorsolateral prefrontal cortex were positively associated with inattention symptoms. Left hippocampal volume was negatively associated with hyperactivity symptoms. The brain volume-inattention/hyperactivity symptom associations were stronger when anxiety/depression symptoms were controlled for. Conclusion: Inattention and hyperactivity symptoms in middle-aged adults are associated with different brain regions and co-occurring anxiety/depression symptoms moderate these brain-behavior relationships. (J. of Att. Dis. XXXX; XX(X) XX-XX). PMID:24567365

  7. Brain

    MedlinePlus

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  8. Perinatal Risk Factors Altering Regional Brain Structure in the Preterm Infant

    ERIC Educational Resources Information Center

    Thompson, Deanne K.; Warfield, Simon K.; Carlin, John B.; Pavlovic, Masa; Wang, Hong X.; Bear, Merilyn; Kean, Michael J.; Doyle, Lex W.; Egan, Gary F.; Inder, Terrie E.

    2007-01-01

    Neuroanatomical structure appears to be altered in preterm infants, but there has been little insight into the major perinatal risk factors associated with regional cerebral structural alterations. MR images were taken to quantitatively compare regional brain tissue volumes between term and preterm infants and to investigate associations between…

  9. On-Line Statistical Segmentation of a Non-Speech Auditory Stream in Neonates as Demonstrated by Event-Related Brain Potentials

    ERIC Educational Resources Information Center

    Kudo, Noriko; Nonaka, Yulri; Mizuno, Noriko; Mizuno, Katsumi; Okanoya, Kazuo

    2011-01-01

    The ability to statistically segment a continuous auditory stream is one of the most important preparations for initiating language learning. Such ability is available to human infants at 8 months of age, as shown by a behavioral measurement. However, behavioral study alone cannot determine how early this ability is available. A recent study using…

  10. Brain regions associated with visual cues are important for bird migration.

    PubMed

    Vincze, Orsolya; Vágási, Csongor I; Pap, Péter L; Osváth, Gergely; Møller, Anders Pape

    2015-11-01

    Long-distance migratory birds have relatively smaller brains than short-distance migrants or residents. Here, we test whether reduction in brain size with migration distance can be generalized across the different brain regions suggested to play key roles in orientation during migration. Based on 152 bird species, belonging to 61 avian families from six continents, we show that the sizes of both the telencephalon and the whole brain decrease, and the relative size of the optic lobe increases, while cerebellum size does not change with increasing migration distance. Body mass, whole brain size, optic lobe size and wing aspect ratio together account for a remarkable 46% of interspecific variation in average migration distance across bird species. These results indicate that visual acuity might be a primary neural adaptation to the ecological challenge of migration. PMID:26538538

  11. Estrogenic modulation of auditory processing: a vertebrate comparison

    PubMed Central

    Caras, Melissa L.

    2013-01-01

    Sex-steroid hormones are well-known regulators of vocal motor behavior in several organisms. A large body of evidence now indicates that these same hormones modulate processing at multiple levels of the ascending auditory pathway. The goal of this review is to provide a comparative analysis of the role of estrogens in vertebrate auditory function. Four major conclusions can be drawn from the literature: First, estrogens may influence the development of the mammalian auditory system. Second, estrogenic signaling protects the mammalian auditory system from noise- and age-related damage. Third, estrogens optimize auditory processing during periods of reproductive readiness in multiple vertebrate lineages. Finally, brain-derived estrogens can act locally to enhance auditory response properties in at least one avian species. This comparative examination may lead to a better appreciation of the role of estrogens in the processing of natural vocalizations and may provide useful insights toward alleviating auditory dysfunctions emanating from hormonal imbalances. PMID:23911849

  12. Auditory fMRI of Sound Intensity and Loudness for Unilateral Stimulation.

    PubMed

    Behler, Oliver; Uppenkamp, Stefan

    2016-01-01

    We report a systematic exploration of the interrelation of sound intensity, ear of entry, individual loudness judgments, and brain activity across hemispheres, using auditory functional magnetic resonance imaging (fMRI). The stimuli employed were 4 kHz-bandpass filtered noise stimuli, presented monaurally to each ear at levels from 37 to 97 dB SPL. One diotic condition and a silence condition were included as control conditions. Normal hearing listeners completed a categorical loudness scaling procedure with similar stimuli before auditory fMRI was performed. The relationship between brain activity, as inferred from blood oxygenation level dependent (BOLD) contrasts, and both sound intensity and loudness estimates were analyzed by means of linear mixed effects models for various anatomically defined regions of interest in the ascending auditory pathway and in the cortex. The results indicate distinct functional differences between midbrain and cortical areas as well as between specific regions within auditory cortex, suggesting a systematic hierarchy in terms of lateralization and the representation of sensory stimulation and perception. PMID:27080657

  13. Developmental stress impairs performance on an association task in male and female songbirds, but impairs auditory learning in females only.

    PubMed

    Farrell, Tara M; Morgan, Amanda; MacDougall-Shackleton, Scott A

    2016-01-01

    In songbirds, early-life environments critically shape song development. Many studies have demonstrated that developmental stress impairs song learning and the development of song-control regions of the brain in males. However, song has evolved through signaller-receiver networks and the effect stress has on the ability to receive auditory signals is equally important, especially for females who use song as an indicator of mate quality. Female song preferences have been the metric used to evaluate how developmental stress affects auditory learning, but preferences are shaped by many non-cognitive factors and preclude the evaluation of auditory learning abilities in males. To determine whether developmental stress specifically affects auditory learning in both sexes, we subjected juvenile European starlings, Sturnus vulgaris, to either an ad libitum or an unpredictable food supply treatment from 35 to 115 days of age. In adulthood, we assessed learning of both auditory and visual discrimination tasks. Females reared in the experimental group were slower than females in the control group to acquire a relative frequency auditory task, and slower than their male counterparts to acquire an absolute frequency auditory task. There was no difference in auditory performance between treatment groups for males. However, on the colour association task, birds from the experimental group committed more errors per trial than control birds. There was no correlation in performance across the cognitive tasks. Developmental stress did not affect all cognitive processes equally across the sexes. Our results suggest that the male auditory system may be more robust to developmental stress than that of females. PMID:26238792

  14. Electrostimulation mapping of comprehension of auditory and visual words.

    PubMed

    Roux, Franck-Emmanuel; Miskin, Krasimir; Durand, Jean-Baptiste; Sacko, Oumar; Réhault, Emilie; Tanova, Rositsa; Démonet, Jean-François

    2015-10-01

    In order to spare functional areas during the removal of brain tumours, electrical stimulation mapping was used in 90 patients (77 in the left hemisphere and 13 in the right; 2754 cortical sites tested). Language functions were studied with a special focus on comprehension of auditory and visual words and the semantic system. In addition to naming, patients were asked to perform pointing tasks from auditory and visual stimuli (using sets of 4 different images controlled for familiarity), and also auditory object (sound recognition) and Token test tasks. Ninety-two auditory comprehension interference sites were observed. We found that the process of auditory comprehension involved a few, fine-grained, sub-centimetre cortical territories. Early stages of speech comprehension seem to relate to two posterior regions in the left superior temporal gyrus. Downstream lexical-semantic speech processing and sound analysis involved 2 pathways, along the anterior part of the left superior temporal gyrus, and posteriorly around the supramarginal and middle temporal gyri. Electrostimulation experimentally dissociated perceptual consciousness attached to speech comprehension. The initial word discrimination process can be considered as an "automatic" stage, the attention feedback not being impaired by stimulation as would be the case at the lexical-semantic stage. Multimodal organization of the superior temporal gyrus was also detected since some neurones could be involved in comprehension of visual material and naming. These findings demonstrate a fine graded, sub-centimetre, cortical representation of speech comprehension processing mainly in the left superior temporal gyrus and are in line with those described in dual stream models of language comprehension processing. PMID:26332785

  15. Electrophysiological measurement of human auditory function

    NASA Technical Reports Server (NTRS)

    Galambos, R.

    1975-01-01

    Contingent negative variations in the presence and amplitudes of brain potentials evoked by sound are considered. Evidence is produced that the evoked brain stem response to auditory stimuli is clearly related to brain events associated with cognitive processing of acoustic signals since their properties depend upon where the listener directs his attention, whether the signal is an expected event or a surprise, and when sound that is listened-for is heard at last.

  16. Data for behavioral results and brain regions showing a time effect during pair-association retrieval.

    PubMed

    Jimura, Koji; Hirose, Satoshi; Wada, Hiroyuki; Yoshizawa, Yasunori; Imai, Yoshio; Akahane, Masaaki; Machida, Toru; Shirouzu, Ichiro; Koike, Yasuharu; Konishi, Seiki

    2016-09-01

    The current data article provides behavioral and neuroimaging data for the research article "Relatedness-dependent rapid development of brain activity in anterior temporal cortex during pair-association retrieval" (Jimura et al., 2016) [1]. Behavioral performance is provided in a table. Fig. 2 of the article is based on this table. Brain regions showing time effect are provided in a table. A statistical activation map for the time effect is shown in Fig. 3C of the article. PMID:27508239

  17. Light Scattering Properties Vary across Different Regions of the Adult Mouse Brain

    PubMed Central

    Stubblefield, Elizabeth A.; Felsen, Gidon

    2013-01-01

    Recently developed optogenetic tools provide powerful approaches to optically excite or inhibit neural activity. In a typical in-vivo experiment, light is delivered to deep nuclei via an implanted optical fiber. Light intensity attenuates with increasing distance from the fiber tip, determining the volume of tissue in which optogenetic proteins can successfully be activated. However, whether and how this volume of effective light intensity varies as a function of brain region or wavelength has not been systematically studied. The goal of this study was to measure and compare how light scatters in different areas of the mouse brain. We delivered different wavelengths of light via optical fibers to acute slices of mouse brainstem, midbrain and forebrain tissue. We measured light intensity as a function of distance from the fiber tip, and used the data to model the spread of light in specific regions of the mouse brain. We found substantial differences in effective attenuation coefficients among different brain areas, which lead to substantial differences in light intensity demands for optogenetic experiments. The use of light of different wavelengths additionally changes how light illuminates a given brain area. We created a brain atlas of effective attenuation coefficients of the adult mouse brain, and integrated our data into an application that can be used to estimate light scattering as well as required light intensity for optogenetic manipulation within a given volume of tissue. PMID:23874433

  18. Attentional performance is correlated with the local regional efficiency of intrinsic brain networks

    PubMed Central

    Xu, Junhai; Yin, Xuntao; Ge, Haitao; Han, Yan; Pang, Zengchang; Tang, Yuchun; Liu, Baolin; Liu, Shuwei

    2015-01-01

    Attention is a crucial brain function for human beings. Using neuropsychological paradigms and task-based functional brain imaging, previous studies have indicated that widely distributed brain regions are engaged in three distinct attention subsystems: alerting, orienting and executive control (EC). Here, we explored the potential contribution of spontaneous brain activity to attention by examining whether resting-state activity could account for individual differences of the attentional performance in normal individuals. The resting-state functional images and behavioral data from attention network test (ANT) task were collected in 59 healthy subjects. Graph analysis was conducted to obtain the characteristics of functional brain networks and linear regression analyses were used to explore their relationships with behavioral performances of the three attentional components. We found that there was no significant relationship between the attentional performance and the global measures, while the attentional performance was associated with specific local regional efficiency. These regions related to the scores of alerting, orienting and EC largely overlapped with the regions activated in previous task-related functional imaging studies, and were consistent with the intrinsic dorsal and ventral attention networks (DAN/VAN). In addition, the strong associations between the attentional performance and specific regional efficiency suggested that there was a possible relationship between the DAN/VAN and task performances in the ANT. We concluded that the intrinsic activity of the human brain could reflect the processing efficiency of the attention system. Our findings revealed a robust evidence for the functional significance of the efficiently organized intrinsic brain network for highly productive cognitions and the hypothesized role of the DAN/VAN at rest. PMID:26283939

  19. Toward Epileptic Brain Region Detection Based on Magnetic Nanoparticle Patterning

    PubMed Central

    Pedram, Maysam Z.; Shamloo, Amir; Alasty, Aria; Ghafar-Zadeh, Ebrahim

    2015-01-01

    Resection of the epilepsy foci is the best treatment for more than 15% of epileptic patients or 50% of patients who are refractory to all forms of medical treatment. Accurate mapping of the locations of epileptic neuronal networks can result in the complete resection of epileptic foci. Even though currently electroencephalography is the best technique for mapping the epileptic focus, it cannot define the boundary of epilepsy that accurately. Herein we put forward a new accurate brain mapping technique using superparamagnetic nanoparticles (SPMNs). The main hypothesis in this new approach is the creation of super-paramagnetic aggregates in the epileptic foci due to high electrical and magnetic activities. These aggregates may improve tissue contrast of magnetic resonance imaging (MRI) that results in improving the resection of epileptic foci. In this paper, we present the mathematical models before discussing the simulation results. Furthermore, we mimic the aggregation of SPMNs in a weak magnetic field using a low-cost microfabricated device. Based on these results, the SPMNs may play a crucial role in diagnostic epilepsy and the subsequent treatment of this disease. PMID:26402686

  20. Toward Epileptic Brain Region Detection Based on Magnetic Nanoparticle Patterning.

    PubMed

    Pedram, Maysam Z; Shamloo, Amir; Alasty, Aria; Ghafar-Zadeh, Ebrahim

    2015-01-01

    Resection of the epilepsy foci is the best treatment for more than 15% of epileptic patients or 50% of patients who are refractory to all forms of medical treatment. Accurate mapping of the locations of epileptic neuronal networks can result in the complete resection of epileptic foci. Even though currently electroencephalography is the best technique for mapping the epileptic focus, it cannot define the boundary of epilepsy that accurately. Herein we put forward a new accurate brain mapping technique using superparamagnetic nanoparticles (SPMNs). The main hypothesis in this new approach is the creation of super-paramagnetic aggregates in the epileptic foci due to high electrical and magnetic activities. These aggregates may improve tissue contrast of magnetic resonance imaging (MRI) that results in improving the resection of epileptic foci. In this paper, we present the mathematical models before discussing the simulation results. Furthermore, we mimic the aggregation of SPMNs in a weak magnetic field using a low-cost microfabricated device. Based on these results, the SPMNs may play a crucial role in diagnostic epilepsy and the subsequent treatment of this disease. PMID:26402686

  1. Visual modulation of auditory responses in the owl inferior colliculus.

    PubMed

    Bergan, Joseph F; Knudsen, Eric I

    2009-06-01

    The barn owl's central auditory system creates a map of auditory space in the external nucleus of the inferior colliculus (ICX). Although the crucial role visual experience plays in the formation and maintenance of this auditory space map is well established, the mechanism by which vision influences ICX responses remains unclear. Surprisingly, previous experiments have found that in the absence of extensive pharmacological manipulation, visual stimuli do not drive neural responses in the ICX. Here we investigated the influence of dynamic visual stimuli on auditory responses in the ICX. We show that a salient visual stimulus, when coincident with an auditory stimulus, can modulate auditory responses in the ICX even though the same visual stimulus may elicit no neural responses when presented alone. For each ICX neuron, the most effective auditory and visual stimuli were located in the same region of space. In addition, the magnitude of the visual modulation of auditory responses was dependent on the context of the stimulus presentation with novel visual stimuli eliciting consistently larger response modulations than frequently presented visual stimuli. Thus the visual modulation of ICX responses is dependent on the characteristics of the visual stimulus as well as on the spatial and temporal correspondence of the auditory and visual stimuli. These results demonstrate moment-to-moment visual enhancements of auditory responsiveness that, in the short-term, increase auditory responses to salient bimodal stimuli and in the long-term could serve to instruct the adaptive auditory plasticity necessary to maintain accurate auditory orienting behavior. PMID:19321633

  2. Circuit-wide Transcriptional Profiling Reveals Brain Region-Specific Gene Networks Regulating Depression Susceptibility.

    PubMed

    Bagot, Rosemary C; Cates, Hannah M; Purushothaman, Immanuel; Lorsch, Zachary S; Walker, Deena M; Wang, Junshi; Huang, Xiaojie; Schlüter, Oliver M; Maze, Ian; Peña, Catherine J; Heller, Elizabeth A; Issler, Orna; Wang, Minghui; Song, Won-Min; Stein, Jason L; Liu, Xiaochuan; Doyle, Marie A; Scobie, Kimberly N; Sun, Hao Sheng; Neve, Rachael L; Geschwind, Daniel; Dong, Yan; Shen, Li; Zhang, Bin; Nestler, Eric J

    2016-06-01

    Depression is a complex, heterogeneous disorder and a leading contributor to the global burden of disease. Most previous research has focused on individual brain regions and genes contributing to depression. However, emerging evidence in humans and animal models suggests that dysregulated circuit function and gene expression across multiple brain regions drive depressive phenotypes. Here, we performed RNA sequencing on four brain regions from control animals and those susceptible or resilient to chronic social defeat stress at multiple time points. We employed an integrative network biology approach to identify transcriptional networks and key driver genes that regulate susceptibility to depressive-like symptoms. Further, we validated in vivo several key drivers and their associated transcriptional networks that regulate depression susceptibility and confirmed their functional significance at the levels of gene transcription, synaptic regulation, and behavior. Our study reveals novel transcriptional networks that control stress susceptibility and offers fundamentally new leads for antidepressant drug discovery. PMID:27181059

  3. Functional photoacoustic imaging to observe regional brain activation induced by cocaine hydrochloride

    NASA Astrophysics Data System (ADS)

    Jo, Janggun; Yang, Xinmai

    2011-09-01

    Photoacoustic microscopy (PAM) was used to detect small animal brain activation in response to drug abuse. Cocaine hydrochloride in saline solution was injected into the blood stream of Sprague Dawley rats through tail veins. The rat brain functional change in response to the injection of drug was then monitored by the PAM technique. Images in the coronal view of the rat brain at the locations of 1.2 and 3.4 mm posterior to bregma were obtained. The resulted photoacoustic (PA) images showed the regional changes in the blood volume. Additionally, the regional changes in blood oxygenation were also presented. The results demonstrated that PA imaging is capable of monitoring regional hemodynamic changes induced by drug abuse.

  4. Sodium tungstate induced neurological alterations in rat brain regions and their response to antioxidants.

    PubMed

    Sachdeva, Sherry; Pant, Satish C; Kushwaha, Pramod; Bhargava, Rakesh; Flora, Swaran J S

    2015-08-01

    Tungsten, recognized recently as an environmental contaminant, is being used in arms and ammunitions as substitute to depleted uranium. We studied the effects of sodium tungstate on oxidative stress, few selected neurological variables like acetylcholinesterase, biogenic amines in rat brain regions (cerebral cortex, hippocampus and cerebellum) and their prevention following co-administration of N-acetylcysteine (NAC), naringenin and quercetin. Animals were sub-chronically exposed to sodium tungstate (100 ppm in drinking water) and orally co-supplemented with different antioxidants (0.30 mM) for three months. Sodium tungstate significantly decreased the activity of acetylcholinesterase, dopamine, nor-epinephrine and 5-hydroxytryptamine levels while it increased monoamine oxidase activity in different brain regions. Tungstate exposure produced a significant increase in biochemical variables indicative of oxidative stress while, neurological alterations were more pronounced in the cerebral cortex compared to other regions. Co-administration of NAC and flavonoids with sodium tungstate significantly restored glutathione, prevented changes in the brain biogenic amines, reactive oxygen species (ROS) and TBARS levels in the different brain regions. The protection was more prominent in the animals co-administered with NAC. We can thus conclude that sodium tungstate induced brain oxidative stress and the alterations in some neurological variables can effectively be reduced by co-supplementation of NAC. PMID:25983264

  5. Auditory Resting-State Network Connectivity in Tinnitus: A Functional MRI Study

    PubMed Central

    Maudoux, Audrey; Lefebvre, Philippe; Cabay, Jean-Evrard; Demertzi, Athena; Vanhaudenhuyse, Audrey; Laureys, Steven; Soddu, Andrea

    2012-01-01

    The underlying functional neuroanatomy of tinnitus remains poorly understood. Few studies have focused on functional cerebral connectivity changes in tinnitus patients. The aim of this study was to test if functional MRI “resting-state” connectivity patterns in auditory network differ between tinnitus patients and normal controls. Thirteen chronic tinnitus subjects and fifteen age-matched healthy controls were studied on a 3 tesla MRI. Connectivity was investigated using independent component analysis and an automated component selection approach taking into account the spatial and temporal properties of each component. Connectivity in extra-auditory regions such as brainstem, basal ganglia/NAc, cerebellum, parahippocampal, right prefrontal, parietal, and sensorimotor areas was found to be increased in tinnitus subjects. The right primary auditory cortex, left prefrontal, left fusiform gyrus, and bilateral occipital regions showed a decreased connectivity in tinnitus. These results show that there is a modification of cortical and subcortical functional connectivity in tinnitus encompassing attentional, mnemonic, and emotional networks. Our data corroborate the hypothesized implication of non-auditory regions in tinnitus physiopathology and suggest that various regions of the brain seem involved in the persistent awareness of the phenomenon as well as in the development of the associated distress leading to disabling chronic tinnitus. PMID:22574141

  6. Regional Brain [11C]carfentanil Binding Following Tobacco Smoking

    PubMed Central

    Domino, Edward F; Hirasawa-Fujita, Mika; Ni, Lisong; Guthrie, Sally K; Zubieta, Jon Kar

    2015-01-01

    Objective To determine if overnight tobacco abstinent carriers of the AG or GG (*G) vs. the AA variant of the human mu opioid receptor (OPRM1) A118G polymorphism (rs1799971) differ in [11C]carfentanil binding after tobacco smoking. Methods Twenty healthy American male smokers who abstained from tobacco overnight were genotyped and completed positron emission tomography (PET) scans with the mu opioid receptor agonist, [11C]carfentanil. They smoked deniconized (denic) and average nicotine (avnic) cigarettes during the PET scans. Results Smoking avnic cigarette decreased the binding potential (BPND) of [11C]carfentanil in the right medial prefrontal cortex (mPfc; 6,56,18), left anterior medial prefrontal cortex (amPfc; −2,46,44), right ventral striatum (vStr; 16, 3, −10), left insula (Ins; −42,10, −12), right hippocampus (Hippo; 18, −6, −14) and left cerebellum (Cbl; −10, −88, −34), and increased the BPND in left amygdala (Amy; −20,0, −22), left putamen (Put; −22, 10, −6) and left nucleus accumbens (NAcc; −10,12, −8). In the AA allele carriers, avnic cigarette smoking significantly changed the BPND compared to after denic smoking in most brain areas listed above. However in the *G carriers the significant BPND changes were confirmed in only amPfc and vStr. Free mu opioid receptor availability was significantly less in the *G than the AA carriers in the Amy and NAcc. Conclusion The present study demonstrates BPND changes induced by avnic smoking in OPRM1 *G carriers were blunted compared to the AA carriers. Also *G smokers had less free mu opioid receptor availability in Amy and NAcc. PMID:25598501

  7. Longitudinal change in regional brain volumes in prodromal Huntington disease

    PubMed Central

    Aylward, Elizabeth H.; Nopoulos, Peggy C.; Ross, Christopher A.; Langbehn, Douglas R.; Pierson, Ronald K.; Mills, James A.; Johnson, Hans J.; Magnotta, Vincent A.; Juhl, Andrew R.; Paulsen, Jane S.

    2011-01-01

    Objective As therapeutics are being developed to target the underlying neuropathology of Huntington disease (HD), interest is increasing in methodologies for conducting clinical trials in the prodromal phase. This study was designed to examine the potential utility of structural MRI measures as outcome measures for such trials. Methods Data are presented from 211 prodromal individuals and 60 controls, scanned both at baseline and two-year follow-up. Prodromal participants were divided into groups based on proximity to estimated onset of diagnosable clinical disease: Far (>15 years from estimated onset); Mid (9–15 years); and Near (<9 years). Volumetric measurements of caudate, putamen, total striatum, globus pallidus, thalamus, total gray and white matter, and CSF were performed. Results All prodromal groups showed a faster rate of atrophy than Controls in striatum, total brain, and cerebral white matter (especially in the frontal lobe). Neither prodromal participants nor Controls showed significant longitudinal change in cortex (either total cortical gray or within individual lobes). When normal age-related atrophy (i.e., change observed in the Control group) was taken into account, there was more statistically significant disease-related atrophy in white matter than in striatum. Conclusion Measures of volume change in striatum and white matter volume, particularly in the frontal lobe, may serve as excellent outcome measures for future clinical trials in prodromal HD. Clinical trials using white matter or striatal volume change as an outcome measure will be most efficient if the sample is restricted to individuals who are within 15 years of estimated onset of diagnosable disease. PMID:20884680

  8. Auditory spatial attention representations in the human cerebral cortex.

    PubMed

    Kong, Lingqiang; Michalka, Samantha W; Rosen, Maya L; Sheremata, Summer L; Swisher, Jascha D; Shinn-Cunningham, Barbara G; Somers, David C

    2014-03-01

    Auditory spatial attention serves important functions in auditory source separation and selection. Although auditory spatial attention mechanisms have been generally investigated, the neural substrates encoding spatial information acted on by attention have not been identified in the human neocortex. We performed functional magnetic resonance imaging experiments to identify cortical regions that support auditory spatial attention and to test 2 hypotheses regarding the coding of auditory spatial attention: 1) auditory spatial attention might recruit the visuospatial maps of the intraparietal sulcus (IPS) to create multimodal spatial attention maps; 2) auditory spatial information might be encoded without explicit cortical maps. We mapped visuotopic IPS regions in individual subjects and measured auditory spatial attention effects within these regions of interest. Contrary to the multimodal map hypothesis, we observed that auditory spatial attentional modulations spared the visuotopic maps of IPS; the parietal regions activated by auditory attention lacked map structure. However, multivoxel pattern analysis revealed that the superior temporal gyrus and the supramarginal gyrus contained significant information about the direction of spatial attention. These findings support the hypothesis that auditory spatial information is coded without a cortical map representation. Our findings suggest that audiospatial and visuospatial attention utilize distinctly different spatial coding schemes. PMID:23180753

  9. Changes in Dietary Iron Exacerbate Regional Brain Manganese Accumulation as Determined by Magnetic Resonance Imaging

    PubMed Central

    Fitsanakis, Vanessa A.; Zhang, Na; Avison, Malcolm J.; Erikson, Keith M.; Gore, John C.; Aschner, Michael

    2011-01-01

    Manganese (Mn) is an essential metal required for normal homeostasis. Humans chronically exposed to high Mn levels, however, may exhibit psychomotor signs secondary to increased brain Mn. As Mn and iron (Fe) share several cellular membrane transporters, decreased Fe levels resulting from Fe deficiency or anemia lead to increased brain Mn deposition. Conversely, decreased Mn levels are associated with abnormal brain Fe accumulation. To reduce potential Mn toxicity resulting from brain Mn accumulation, we proposed that increased dietary Fe would attenuate brain Mn deposition. To test this hypothesis, three groups of Sprague-Dawley rats were injected weekly (14 weeks) with Mn (3 mg/kg) and fed normal Fe (TX), Fe-supplemented (FeS), or Fe-deficient (FeD) chow. Control (CN) rats received normal dietary Fe and saline injections. Using magnetic resonance imaging, rats were imaged biweekly for 14 weeks to qualitatively monitor brain Mn and Fe accumulation. Both FeS and FeD had greater brain Mn deposition than TX rats. By week 3, R1 values, which correlate with Mn deposition, were statistically significantly increased (p < 0.05) in brain stem, cerebellum, cortex, midbrain, and striatum compared with CN or TX animals. By week 14, R1 values for all brain regions in FeS and FeD animals were statistically significantly increased (p < 0.05). By the end of the study, similar results were obtained for R2 values, a marker of Fe accumulation. These data suggest that Fe supplementation does not effectively protect and may even exacerbate brain Mn accumulation in mammals subchronically exposed to Mn. PMID:21177776

  10. Rheological regional properties of brain tissue studied under cyclic creep/ recovery shear stresses

    NASA Astrophysics Data System (ADS)

    Boudjema, F.; Lounis, M.; Khelidj, B.; Bessai, N.

    2015-04-01

    The rheological properties of brain tissue were studied by repeated creep-recovery shear tests under static conditions for different regions. Corpus callosum CC, Thalamus Th and Corona radiata CR. Non-linear viscoelastic model was also proposed to characterize the transient/steady states of shear creep results. From the creep-recovery data it was obvious that the brain tissues show high regional anisotropy. However. the both samples exhibit fluid viscoelastic properties in the first shear stress cycle of 100 Pa, while this behaviour evolutes to solid viscoelastic with cyclic effect.

  11. Music training relates to the development of neural mechanisms of selective auditory attention.

    PubMed

    Strait, Dana L; Slater, Jessica; O'Connell, Samantha; Kraus, Nina

    2015-04-01

    Selective attention decreases trial-to-trial variability in cortical auditory-evoked activity. This effect increases over the course of maturation, potentially reflecting the gradual development of selective attention and inhibitory control. Work in adults indicates that music training may alter the development of this neural response characteristic, especially over brain regions associated with executive control: in adult musicians, attention decreases variability in auditory-evoked responses recorded over prefrontal cortex to a greater extent than in nonmusicians. We aimed to determine whether this musician-associated effect emerges during childhood, when selective attention and inhibitory control are under development. We compared cortical auditory-evoked variability to attended and ignored speech streams in musicians and nonmusicians across three age groups: preschoolers, school-aged children and young adults. Results reveal that childhood music training is associated with reduced auditory-evoked response variability recorded over prefrontal cortex during selective auditory attention in school-aged child and adult musicians. Preschoolers, on the other hand, demonstrate no impact of selective attention on cortical response variability and no musician distinctions. This finding is consistent with the gradual emergence of attention during this period and may suggest no pre-existing differences in this attention-related cortical metric between children who undergo music training and those who do not. PMID:25660985

  12. McGurk illusion recalibrates subsequent auditory perception.

    PubMed

    Lüttke, Claudia S; Ekman, Matthias; van Gerven, Marcel A J; de Lange, Floris P

    2016-01-01

    Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of 'ada'. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we asked whether the altered auditory perception due to the McGurk illusion affects subsequent auditory perception, i.e. whether this process of fusion may cause a recalibration of the auditory boundaries between phonemes. Participants categorized auditory and audiovisual speech stimuli as /aba/, /ada/ or /aga/ while activity patterns in their auditory cortices were recorded using fMRI. Interestingly, following a McGurk illusion, an auditory /aba/ was more often misperceived as 'ada'. Furthermore, we observed a neural counterpart of this recalibration in the early auditory cortex. When the auditory input /aba/ was perceived as 'ada', activity patterns bore stronger resemblance to activity patterns elicited by /ada/ sounds than when they were correctly perceived as /aba/. Our results suggest that upon experiencing the McGurk illusion, the brain shifts the neural representation of an /aba/ sound towards /ada/, culminating in a recalibration in perception of subsequent auditory input. PMID:27611960

  13. McGurk illusion recalibrates subsequent auditory perception

    PubMed Central

    Lüttke, Claudia S.; Ekman, Matthias; van Gerven, Marcel A. J.; de Lange, Floris P.

    2016-01-01

    Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of ‘ada’. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we asked whether the altered auditory perception due to the McGurk illusion affects subsequent auditory perception, i.e. whether this process of fusion may cause a recalibration of the auditory boundaries between phonemes. Participants categorized auditory and audiovisual speech stimuli as /aba/, /ada/ or /aga/ while activity patterns in their auditory cortices were recorded using fMRI. Interestingly, following a McGurk illusion, an auditory /aba/ was more often misperceived as ‘ada’. Furthermore, we observed a neural counterpart of this recalibration in the early auditory cortex. When the auditory input /aba/ was perceived as ‘ada’, activity patterns bore stronger resemblance to activity patterns elicited by /ada/ sounds than when they were correctly perceived as /aba/. Our results suggest that upon experiencing the McGurk illusion, the brain shifts the neural representation of an /aba/ sound towards /ada/, culminating in a recalibration in perception of subsequent auditory input. PMID:27611960

  14. Auditory memory function in expert chess players

    PubMed Central

    Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

    2015-01-01

    Background: Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert chess players using the Persian version of dichotic auditory-verbal memory test. Methods: The Persian version of dichotic auditory-verbal memory test was performed for 30 expert chess players aged 20-35 years and 30 non chess players who were matched by different conditions; the participants in both groups were randomly selected. The performance of the two groups was compared by independent samples t-test using SPSS version 21. Results: The mean score of dichotic auditory-verbal memory test between the two groups, expert chess players and non-chess players, revealed a significant difference (p≤ 0.001). The difference between the ears scores for expert chess players (p= 0.023) and non-chess players (p= 0.013) was significant. Gender had no effect on the test results. Conclusion: Auditory memory function in expert chess players was significantly better compared to non-chess players. It seems that increased auditory memory function is related to strengthening cognitive performances due to playing chess for a long time. PMID:26793666

  15. Analysis of spatial-temporal gene expression patterns reveals dynamics and regionalization in developing mouse brain

    PubMed Central

    Chou, Shen-Ju; Wang, Chindi; Sintupisut, Nardnisa; Niou, Zhen-Xian; Lin, Chih-Hsu; Li, Ker-Chau; Yeang, Chen-Hsiang

    2016-01-01

    Allen Brain Atlas (ABA) provides a valuable resource of spatial/temporal gene expressions in mammalian brains. Despite rich information extracted from this database, current analyses suffer from several limitations. First, most studies are either gene-centric or region-centric, thus are inadequate to capture the superposition of multiple spatial-temporal patterns. Second, standard tools of expression analysis such as matrix factorization can capture those patterns but do not explicitly incorporate spatial dependency. To overcome those limitations, we proposed a computational method to detect recurrent patterns in the spatial-temporal gene expression data of developing mouse brains. We demonstrated that regional distinction in brain development could be revealed by localized gene expression patterns. The patterns expressed in the forebrain, medullary and pontomedullary, and basal ganglia are enriched with genes involved in forebrain development, locomotory behavior, and dopamine metabolism respectively. In addition, the timing of global gene expression patterns reflects the general trends of molecular events in mouse brain development. Furthermore, we validated functional implications of the inferred patterns by showing genes sharing similar spatial-temporal expression patterns with Lhx2 exhibited differential expression in the embryonic forebrains of Lhx2 mutant mice. These analysis outcomes confirm the utility of recurrent expression patterns in studying brain development. PMID:26786896

  16. Regional homogeneity of resting-state brain abnormalities in violent juvenile offenders: a biomarker of brain immaturity?

    PubMed

    Chen, Chen; Zhou, Jiansong; Liu, Chunhong; Witt, Katrina; Zhang, Yingdong; Jing, Bin; Li, Chun; Wang, Xiaoping; Li, Lingjiang

    2015-01-01

    The authors investigated whether male violent juvenile offenders demonstrate any differences in local functional connectivity indicative of delayed maturation of the brain that may serve as a biomarker of violence. Twenty-nine violent juvenile offenders and 28 age-matched controls were recruited. Regional homogeneity (ReHo) method was used to analyze resting-state magnetic resonance images. Violent offenders showed significantly lower ReHo values in the right caudate, right medial prefrontal cortex, and left precuneus, and higher values in the right supramarginal gyrus than the controls. These regions had both high sensitivity and specificity in distinguishing between the two groups suggesting that dysfunction in these regions can be used to correctly classify those individuals who are violent. Dysfunction in the right medial prefrontal-caudate circuit may, therefore, represent an important biomarker of violence juvenile males. PMID:25716485

  17. On-line statistical segmentation of a non-speech auditory stream in neonates as demonstrated by event-related brain potentials.

    PubMed

    Kudo, Noriko; Nonaka, Yulri; Mizuno, Noriko; Mizuno, Katsumi; Okanoya, Kazuo

    2011-09-01

    The ability to statistically segment a continuous auditory stream is one of the most important preparations for initiating language learning. Such ability is available to human infants at 8 months of age, as shown by a behavioral measurement. However, behavioral study alone cannot determine how early this ability is available. A recent study using measurements of event-related potential (ERP) revealed that neonates are able to detect statistical boundaries within auditory streams of speech syllables. Extending this line of research will allow us to better understand the cognitive preparation for language acquisition that is available to neonates. The aim of the present study was to examine the domain-generality of such statistical segmentation. Neonates were presented with nonlinguistic tone sequences composed of four tritone units, each consisting of three semitones extracted from one octave, for two 5-minute sessions. Only the first tone of each unit evoked a significant positivity in the frontal area during the second session, but not in the first session. This result suggests that the general ability to distinguish units in an auditory stream by statistical information is activated at birth and is probably innately prepared in humans. PMID:21884325

  18. Brain regional angiogenic potential at the neurovascular unit during normal aging

    PubMed Central

    Murugesan, Nivetha; Demarest, Tyler G.; Madri, Joseph A.; Pachter, Joel S.

    2011-01-01

    Given strong regional specialization of the brain, cerebral angiogenesis may be regionally modified during normal aging. To test this hypothesis, expression of a broad cadre of angiogenesis-associated genes was assayed at the neurovascular unit (NVU) in discrete brain regions of young vs. aged mice by laser capture microdissection coupled to quantitative real-time PCR. Complementary quantitative capillary density/branching studies were performed as well. Effects of physical exercise were also assayed to determine if age-related trends could be reversed. Additionally, gene response to hypoxia was probed to highlight age-associated weaknesses in adapting to this angiogenic stress. Aging impacted resting expression of angiogenesis-associated genes at the NVU in a region-dependent manner. Physical exercise reversed some of these age-associated gene trends, as well as positively influenced cerebral capillary density/branching in a region-dependent way. Lastly, hypoxia revealed a weaker angiogenic response in aged brain. These results suggest heterogeneous changes in angiogenic capacity of the brain during normal aging, and imply a therapeutic benefit of physical exercise that acts at the level of the NVU. PMID:22019053

  19. Chronic Ethanol Exposure Produces Time- and Brain Region-Dependent Changes in Gene Coexpression Networks

    PubMed Central

    Osterndorff-Kahanek, Elizabeth A.; Becker, Howard C.; Lopez, Marcelo F.; Farris, Sean P.; Tiwari, Gayatri R.; Nunez, Yury O.; Harris, R. Adron; Mayfield, R. Dayne

    2015-01-01

    Repeated ethanol exposure and withdrawal in mice increases voluntary drinking and represents an animal model of physical dependence. We examined time- and brain region-dependent changes in gene coexpression networks in amygdala (AMY), nucleus accumbens (NAC), prefrontal cortex (PFC), and liver after four weekly cycles of chronic intermittent ethanol (CIE) vapor exposure in C57BL/6J mice. Microarrays were used to compare gene expression profiles at 0-, 8-, and 120-hours following the last ethanol exposure. Each brain region exhibited a large number of differentially expressed genes (2,000-3,000) at the 0- and 8-hour time points, but fewer changes were detected at the 120-hour time point (400-600). Within each region, there was little gene overlap across time (~20%). All brain regions were significantly enriched with differentially expressed immune-related genes at the 8-hour time point. Weighted gene correlation network analysis identified modules that were highly enriched with differentially expressed genes at the 0- and 8-hour time points with virtually no enrichment at 120 hours. Modules enriched for both ethanol-responsive and cell-specific genes were identified in each brain region. These results indicate that chronic alcohol exposure causes global ‘rewiring‘ of coexpression systems involving glial and immune signaling as well as neuronal genes. PMID:25803291

  20. Chronic Ethanol Consumption Profoundly Alters Regional Brain Ceramide and Sphingomyelin Content in Rodents

    PubMed Central

    2015-01-01

    Ceramides (CER) are involved in alcohol-induced neuroinflammation. In a mouse model of chronic alcohol exposure, 16 CER and 18 sphingomyelin (SM) concentrations from whole brain lipid extracts were measured using electrospray mass spectrometry. All 18 CER concentrations in alcohol exposed adults increased significantly (range: 25–607%); in juveniles, 6 CER decreased (range: −9 to −37%). In contrast, only three SM decreased in adult and one increased significantly in juvenile. Next, regional identification at 50 μm spatial resolution from coronal sections was obtained with matrix implanted laser desorption/ionization mass spectrometry imaging (MILDI-MSI) by implanting silver nanoparticulate matrices followed by focused laser desorption. Most of the CER and SM quantified in whole brain extracts were detected in MILDI images. Coronal sections from three brain levels show qualitative regional changes in CER-SM ion intensities, as a function of group and brain region, in cortex, striatum, accumbens, habenula, and hippocampus. Highly correlated changes in certain white matter CER-SM pairs occur in regions across all groups, including the hippocampus and the lateral (but not medial) cerebellar cortex of adult mice. Our data provide the first microscale MS evidence of regional lipid intensity variations induced by alcohol. PMID:25387107

  1. Regional differences in actomyosin contraction shape the primary vesicles in the embryonic chicken brain

    NASA Astrophysics Data System (ADS)

    Filas, Benjamen A.; Oltean, Alina; Majidi, Shabnam; Bayly, Philip V.; Beebe, David C.; Taber, Larry A.

    2012-12-01

    In the early embryo, the brain initially forms as a relatively straight, cylindrical epithelial tube composed of neural stem cells. The brain tube then divides into three primary vesicles (forebrain, midbrain, hindbrain), as well as a series of bulges (rhombomeres) in the hindbrain. The boundaries between these subdivisions have been well studied as regions of differential gene expression, but the morphogenetic mechanisms that generate these constrictions are not well understood. Here, we show that regional variations in actomyosin-based contractility play a major role in vesicle formation in the embryonic chicken brain. In particular, boundaries did not form in brains exposed to the nonmuscle myosin II inhibitor blebbistatin, whereas increasing contractile force using calyculin or ATP deepened boundaries considerably. Tissue staining showed that contraction likely occurs at the inner part of the wall, as F-actin and phosphorylated myosin are concentrated at the apical side. However, relatively little actin and myosin was found in rhombomere boundaries. To determine the specific physical mechanisms that drive vesicle formation, we developed a finite-element model for the brain tube. Regional apical contraction was simulated in the model, with contractile anisotropy and strength estimated from contractile protein distributions and measurements of cell shapes. The model shows that a combination of circumferential contraction in the boundary regions and relatively isotropic contraction between boundaries can generate realistic morphologies for the primary vesicles. In contrast, rhombomere formation likely involves longitudinal contraction between boundaries. Further simulations suggest that these different mechanisms are dictated by regional differences in initial morphology and the need to withstand cerebrospinal fluid pressure. This study provides a new understanding of early brain morphogenesis.

  2. Region-Specific Defects of Respiratory Capacities in the Ndufs4(KO) Mouse Brain

    PubMed Central

    Kayser, Ernst-Bernhard; Sedensky, Margaret M.; Morgan, Philip G.

    2016-01-01

    Background Lack of NDUFS4, a subunit of mitochondrial complex I (NADH:ubiquinone oxidoreductase), causes Leigh syndrome (LS), a progressive encephalomyopathy. Knocking out Ndufs4, either systemically or in brain only, elicits LS in mice. In patients as well as in KO mice distinct regions of the brain degenerate while surrounding tissue survives despite systemic complex I dysfunction. For the understanding of disease etiology and ultimately for the development of rationale treatments for LS, it appears important to uncover the mechanisms that govern focal neurodegeneration. Results Here we used the Ndufs4(KO) mouse to investigate whether regional and temporal differences in respiratory capacity of the brain could be correlated with neurodegeneration. In the KO the respiratory capacity of synaptosomes from the degeneration prone regions olfactory bulb, brainstem and cerebellum was significantly decreased. The difference was measurable even before the onset of neurological symptoms. Furthermore, neither compensating nor exacerbating changes in glycolytic capacity of the synaptosomes were found. By contrast, the KO retained near normal levels of synaptosomal respiration in the degeneration-resistant/resilient “rest” of the brain. We also investigated non-synaptic mitochondria. The KO expectedly had diminished capacity for oxidative phosphorylation (state 3 respiration) with complex I dependent substrate combinations pyruvate/malate and glutamate/malate but surprisingly had normal activity with α-ketoglutarate/malate. No correlation between oxidative phosphorylation (pyruvate/malate driven state 3 respiration) and neurodegeneration was found: Notably, state 3 remained constant in the KO while in controls it tended to increase with time leading to significant differences between the genotypes in older mice in both vulnerable and resilient brain regions. Neither regional ROS damage, measured as HNE-modified protein, nor regional complex I stability, assessed by blue

  3. Auditory connections and functions of prefrontal cortex

    PubMed Central

    Plakke, Bethany; Romanski, Lizabeth M.

    2014-01-01

    The functional auditory system extends from the ears to the frontal lobes with successively more complex functions occurring as one ascends the hierarchy of the nervous system. Several areas of the frontal lobe receive afferents from both early and late auditory processing regions within the temporal lobe. Afferents from the early part of the cortical auditory system, the auditory belt cortex, which are presumed to carry information regarding auditory features of sounds, project to only a few prefrontal regions and are most dense in the ventrolateral prefrontal cortex (VLPFC). In contrast, projections from the parabelt and the rostral superior temporal gyrus (STG) most likely convey more complex information and target a larger, widespread region of the prefrontal cortex. Neuronal responses reflect these anatomical projections as some prefrontal neurons exhibit responses to features in acoustic stimuli, while other neurons display task-related responses. For example, recording studies in non-human primates indicate that VLPFC is responsive to complex sounds including vocalizations and that VLPFC neurons in area 12/47 respond to sounds with similar acoustic morphology. In contrast, neuronal responses during auditory working memory involve a wider region of the prefrontal cortex. In humans, the frontal lobe is involved in auditory detection, discrimination, and working memory. Past research suggests that dorsal and ventral subregions of the prefrontal cortex process different types of information with dorsal cortex processing spatial/visual information and ventral cortex processing non-spatial/auditory information. While this is apparent in the non-human primate and in some neuroimaging studies, most research in humans indicates that specific task conditions, stimuli or previous experience may bias the recruitment of specific prefrontal regions, suggesting a more flexible role for the frontal lobe during auditory cognition. PMID:25100931

  4. Specific binding of naloxone to ovine brain tissue: comparison of brain regions and endocrine states.

    PubMed

    Weesner, G D; Trout, W E; Malven, P V

    1989-06-01

    Binding of [3H]naloxone ([3H]NAL) to brain membranes was quantified by Scatchard analysis using two methods of separating bound from free [3H]NAL. In the centrifugation method, membranes that were soluble at 1,000 x g, but sedimented at 20,000 x g, were incubated with [3H]NAL. For filtration, all membranes that sedimented at 20,000 x g were incubated and filtered through glass filter fibers. Nonspecific binding was estimated using greater than 500-fold excess of unlabeled naloxone (10(-6) M). Specific binding of [3H]NAL was used to generate linear multiple-point Scatchard plots, which indicated a single class of high-affinity sites. In Exp. 1, 10 ovariectomized (OVX) ewes were injected with estradiol-17 beta alone or in combination with progesterone. Compared with OVX controls, these hormonal treatments did not affect binding of [3H]NAL (centrifugation method) to combined hypothalamus (HYP) + preoptic (POA) tissues. In cyclic ewes (Exp. 2, filtration method), affinity constants (2.4 +/- .2 x 10(8) M-1) did not differ among HYP, POA and basal forebrain (BF) tissues, but BF had more sites (39 +/- 3 fmol/mg) than either HYP (14 +/- 1) or POA (17 +/- 1). Binding affinity and concentration of sites within each brain area (HYP, POA, BF) did not differ between d 8 and d 16 (preovulatory but after luteolysis) in normally cycling ewes. Overall, neural tissue dissected from BF had a greater concentration of binding sites than HYP or POA. Exogenous and endogenous fluctuations in ovarian steroids did not affect binding of [3H]NAL to these tissues. PMID:2768110

  5. REGIONAL LOCALIZATION AND DEVELOPMENTAL EXPRESSION OF THE BCR GENE IN RODENT BRAIN

    PubMed Central

    Fioretos, Thoas; Voncken, Jan Willem; Baram, Tallie Z.; Kamme, Fredrik; Groffen, John; Heisterkamp, Nora

    2013-01-01

    The BCR gene is implicated in the development of Ph-positive leukemia through its fusion with the nonreceptor tyrosine kinase gene ABL. The normal 160 kDa Bcr protein has several functional domains, and recently one specific role for Bcr was established in the regulation of respiratory burst activity in white blood cells. Bcr expression levels are relatively constant throughout mouse development until adulthood in brain and in hematopoietic tissues, a pattern that is distinctly different from that of the functionally related n-chimerin gene. In the present study, RNA in situ hybridization was used to explore the normal cellular function of Bcr in rodent brain and hematopoietic organs. The data pinpoint the high bcr expression in the brain to the hippocampal pyramidal cell layer and the dentate gyrus, and to the piriform cortex and the olfactory nuclei, reflecting a potentially interesting function for Bcr in these highly specialized brain regions. PMID:8581068

  6. Reconstructing speech from human auditory cortex.

    PubMed

    Pasley, Brian N; David, Stephen V; Mesgarani, Nima; Flinker, Adeen; Shamma, Shihab A; Crone, Nathan E; Knight, Robert T; Chang, Edward F

    2012-01-01

    How the human auditory system extracts perceptually relevant acoustic features of speech is unknown. To address this question, we used intracranial recordings from nonprimary auditory cortex in the human superior temporal gyrus to determine what acoustic information in speech sounds can be reconstructed from population neural activity. We found that slow and intermediate temporal fluctuations, such as those corresponding to syllable rate, were accurately reconstructed using a linear model based on the auditory spectrogram. However, reconstruction of fast temporal fluctuations, such as syllable onsets and offsets, required a nonlinear sound representation based on temporal modulation energy. Reconstruction accuracy was highest within the range of spectro-temporal fluctuations that have been found to be critical for speech intelligibility. The decoded speech representations allowed readout and identification of individual words directly from brain activity during single trial sound presentations. These findings reveal neural encoding mechanisms of speech acoustic parameters in higher order human auditory cortex. PMID:22303281

  7. Reconstructing Speech from Human Auditory Cortex

    PubMed Central

    Pasley, Brian N.; David, Stephen V.; Mesgarani, Nima; Flinker, Adeen; Shamma, Shihab A.; Crone, Nathan E.; Knight, Robert T.; Chang, Edward F.

    2012-01-01

    How the human auditory system extracts perceptually relevant acoustic features of speech is unknown. To address this question, we used intracranial recordings from nonprimary auditory cortex in the human superior temporal gyrus to determine what acoustic information in speech sounds can be reconstructed from population neural activity. We found that slow and intermediate temporal fluctuations, such as those corresponding to syllable rate, were accurately reconstructed using a linear model based on the auditory spectrogram. However, reconstruction of fast temporal fluctuations, such as syllable onsets and offsets, required a nonlinear sound representation based on temporal modulation energy. Reconstruction accuracy was highest within the range of spectro-temporal fluctuations that have been found to be critical for speech intelligibility. The decoded speech representations allowed readout and identification of individual words directly from brain activity during single trial sound presentations. These findings reveal neural encoding mechanisms of speech acoustic parameters in higher order human auditory cortex. PMID:22303281

  8. Brain regional pharmacokinetics of /sup 11/C-labeled diphenylhydantoin: positron emission tomography in humans

    SciTech Connect

    Baron, J.C.; Roeda, D.; Munari, C.; Crouzel, C.; Chodkiewicz, J.P.; Comar, D.

    1983-05-01

    We used positron emission tomography to study the regional cerebral pharmacokinetics of /sup 11/C-labeled diphenylhydantoin (/sup 11/C-DPH), which was given intravenously to 10 patients (8 intractable partial epileptics and 2 nonepileptics). In the nonaffected hemisphere, /sup 11/C-DPH concentration in gray matter reached equilibrium with blood within 20 minutes but was still rising at 60 minutes in white matter, where equilibrium was too slow to be detected owing to the fast physical decay of /sup 11/C. Brain-blood concentration ratios at 50 minutes were 1.37 and 1.06 in gray and white matter, respectively, similar but less variable than steady-state DPH ratios reported in human brain surgical samples. There was no indication that normal brain regions of medically resistant epileptics bind DPH less effectively than in nonepileptic patients. Brain and blood /sup 11/C-DPH concentrations were well correlated, confirming that the latter gives a reliable estimate of the former in unaffected brain regions.

  9. Development and iron-dependent expression of hephaestin in different brain regions of rats.

    PubMed

    Qian, Zhong-Ming; Chang, Yan-Zhong; Zhu, Li; Yang, Lei; Du, Jun-Rong; Ho, Kwok-Ping; Wang, Qin; Li, Lian-Zhi; Wang, Chen-Yuen; Ge, Xiaohu; Jing, Niu Li; Li, Lin; Ke, Ya

    2007-12-01

    It has been suggested that Hephaestin (Heph), a newly discovered ceruloplasmin homologue, is necessary for iron egress from the enterocytes into circulation via interacting with ferroportin1 (FP1). Based on the putative function of Heph, and the similarity between the process of iron transport in the enterocytes and that in the blood-brain barrier (BBB) cells, it has also been proposed that Heph plays a similar role in exporting iron from the BBB cells and other brain cells as it works in the enterocytes via interacting with FP1. The existence of FP1 in the brain has been demonstrated. In this study, we investigated Heph expression and effects of development and iron in the cortex, hippocampus, striatum, and substantia nigra. The data demonstrated that all the four regions we examined have the ability to express Heph mRNA and protein. The findings also showed that both the development and iron status have a significant effect on Heph expression and the effects of iron status are regionally specific. It was also suggested that Heph expression is probably regulated at the transcriptional level by the development and iron in these brain regions. These findings, together with other published data, support a putative role of Heph in the iron metabolism in the brain. PMID:17516501

  10. Altered regional homogeneity of spontaneous brain activity in idiopathic trigeminal neuralgia

    PubMed Central

    Wang, Yanping; Zhang, Xiaoling; Guan, Qiaobing; Wan, Lihong; Yi, Yahui; Liu, Chun-Feng

    2015-01-01

    The pathophysiology of idiopathic trigeminal neuralgia (ITN) has conventionally been thought to be induced by neurovascular compression theory. Recent structural brain imaging evidence has suggested an additional central component for ITN pathophysiology. However, far less attention has been given to investigations of the basis of abnormal resting-state brain activity in these patients. The objective of this study was to investigate local brain activity in patients with ITN and its correlation with clinical variables of pain. Resting-state functional magnetic resonance imaging data from 17 patients with ITN and 19 age- and sex-matched healthy controls were analyzed using regional homogeneity (ReHo) analysis, which is a data-driven approach used to measure the regional synchronization of spontaneous brain activity. Patients with ITN had decreased ReHo in the left amygdala, right parahippocampal gyrus, and left cerebellum and increased ReHo in the right inferior temporal gyrus, right thalamus, right inferior parietal lobule, and left postcentral gyrus (corrected). Furthermore, the increase in ReHo in the left precentral gyrus was positively correlated with visual analog scale (r=0.54; P=0.002). Our study found abnormal functional homogeneity of intrinsic brain activity in several regions in ITN, suggesting the maladaptivity of the process of daily pain attacks and a central role for the pathophysiology of ITN. PMID:26508861

  11. Altered regional homogeneity of spontaneous brain activity in idiopathic trigeminal neuralgia.

    PubMed

    Wang, Yanping; Zhang, Xiaoling; Guan, Qiaobing; Wan, Lihong; Yi, Yahui; Liu, Chun-Feng

    2015-01-01

    The pathophysiology of idiopathic trigeminal neuralgia (ITN) has conventionally been thought to be induced by neurovascular compression theory. Recent structural brain imaging evidence has suggested an additional central component for ITN pathophysiology. However, far less attention has been given to investigations of the basis of abnormal resting-state brain activity in these patients. The objective of this study was to investigate local brain activity in patients with ITN and its correlation with clinical variables of pain. Resting-state functional magnetic resonance imaging data from 17 patients with ITN and 19 age- and sex-matched healthy controls were analyzed using regional homogeneity (ReHo) analysis, which is a data-driven approach used to measure the regional synchronization of spontaneous brain activity. Patients with ITN had decreased ReHo in the left amygdala, right parahippocampal gyrus, and left cerebellum and increased ReHo in the right inferior temporal gyrus, right thalamus, right inferior parietal lobule, and left postcentral gyrus (corrected). Furthermore, the increase in ReHo in the left precentral gyrus was positively correlated with visual analog scale (r=0.54; P=0.002). Our study found abnormal functional homogeneity of intrinsic brain activity in several regions in ITN, suggesting the maladaptivity of the process of daily pain attacks and a central role for the pathophysiology of ITN. PMID:26508861

  12. Normative data for subcortical regional volumes over the lifetime of the adult human brain.

    PubMed

    Potvin, Olivier; Mouiha, Abderazzak; Dieumegarde, Louis; Duchesne, Simon

    2016-08-15

    Normative data for volumetric estimates of brain structures are necessary to adequately assess brain volume alterations in individuals with suspected neurological or psychiatric conditions. Although many studies have described age and sex effects in healthy individuals for brain morphometry assessed via magnetic resonance imaging, proper normative values allowing to quantify potential brain abnormalities are needed. We developed norms for volumetric estimates of subcortical brain regions based on cross-sectional magnetic resonance scans from 2790 healthy individuals aged 18 to 94years using 23 samples provided by 21 independent research groups. The segmentation was conducted using FreeSurfer, a widely used and freely available automated segmentation software. Models predicting subcortical regional volumes of each hemisphere were produced including age, sex, estimated total intracranial volume (eTIV), scanner manufacturer, magnetic field strength, and interactions as predictors. The mean explained variance by the models was 48%. For most regions, age, sex and eTIV predicted most of the explained variance while manufacturer, magnetic field strength and interactions predicted a limited amount. Estimates of the expected volumes of an individual based on its characteristics and the scanner characteristics can be obtained using derived formulas. For a new individual, significance test for volume abnormality, effect size and estimated percentage of the normative population with a smaller volume can be obtained. Normative values were validated in independent samples of healthy adults and in adults with Alzheimer's disease and schizophrenia. PMID:27165761

  13. Role of Prion Replication in the Strain-dependent Brain Regional Distribution of Prions.

    PubMed

    Hu, Ping Ping; Morales, Rodrigo; Duran-Aniotz, Claudia; Moreno-Gonzalez, Ines; Khan, Uffaf; Soto, Claudio

    2016-06-10

    One intriguing feature of prion diseases is their strain variation. Prion strains are differentiated by the clinical consequences they generate in the host, their biochemical properties, and their potential to infect other animal species. The selective targeting of these agents to specific brain structures have been extensively used to characterize prion strains. However, the molecular basis dictating strain-specific neurotropism are still elusive. In this study, isolated brain structures from animals infected with four hamster prion strains (HY, DY, 139H, and SSLOW) were analyzed for their content of protease-resistant PrP(Sc) Our data show that these strains have different profiles of PrP deposition along the brain. These patterns of accumulation, which were independent of regional PrP(C) production, were not reproduced by in vitro replication when different brain regions were used as substrate for the misfolding-amplification reaction. On the contrary, our results show that in vitro replication efficiency depended exclusively on the amount of PrP(C) present in each part of the brain. Our results suggest that the variable regional distribution of PrP(Sc) in distinct strains is not determined by differences on prion formation, but on other factors or cellular pathways. Our findings may contribute to understand the molecular mechanisms of prion pathogenesis and strain diversity. PMID:27056328

  14. Age- and brain region-dependent α-synuclein oligomerization is attributed to alterations in intrinsic enzymes regulating α-synuclein phosphorylation in aging monkey brains

    PubMed Central

    Chen, Min; Yang, Weiwei; Li, Xin; Li, Xuran; Wang, Peng; Yue, Feng; Yang, Hui; Chan, Piu; Yu, Shun

    2016-01-01

    We previously reported that the levels of α-syn oligomers, which play pivotal pathogenic roles in age-related Parkinson's disease (PD) and dementia with Lewy bodies, increase heterogeneously in the aging brain. Here, we show that exogenous α-syn incubated with brain extracts from older cynomolgus monkeys and in Lewy body pathology (LBP)-susceptible brain regions (striatum and hippocampus) forms higher amounts of phosphorylated and oligomeric α-syn than that in extracts from younger monkeys and LBP-insusceptible brain regions (cerebellum and occipital cortex). The increased α-syn phosphorylation and oligomerization in the brain extracts from older monkeys and in LBP-susceptible brain regions were associated with higher levels of polo-like kinase 2 (PLK2), an enzyme promoting α-syn phosphorylation, and lower activity of protein phosphatase 2A (PP2A), an enzyme inhibiting α-syn phosphorylation, in these brain extracts. Further, the extent of the age- and brain-dependent increase in α-syn phosphorylation and oligomerization was reduced by inhibition of PLK2 and activation of PP2A. Inversely, phosphorylated α-syn oligomers reduced the activity of PP2A and showed potent cytotoxicity. In addition, the activity of GCase and the levels of ceramide, a product of GCase shown to activate PP2A, were lower in brain extracts from older monkeys and in LBP-susceptible brain regions. Our results suggest a role for altered intrinsic metabolic enzymes in age- and brain region-dependent α-syn oligomerization in aging brains. PMID:27032368

  15. Decreased auditory GABA+ concentrations in presbycusis demonstrated by edited magnetic resonance spectroscopy

    PubMed Central

    Gao, Fei; Wang, Guangbin; Ma, Wen; Ren, Fuxin; Li, Muwei; Dong, Yuling; Liu, Cheng; Liu, Bo; Bai, Xue; Zhao, Bin; Edden, Richard A.E.

    2014-01-01

    Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the central auditory system. Altered GABAergic neurotransmission has been found in both the inferior colliculus and the auditory cortex in animal models of presbycusis. Edited magnetic resonance spectroscopy (MRS), using the MEGA-PRESS sequence, is the most widely used technique for detecting GABA in the human brain. However, to date there has been a paucity of studies exploring changes to the GABA concentrations in the auditory region of patients with presbycusis. In this study, sixteen patients with presbycusis (5 males/11 females, mean age 63.1 ± 2.6 years) and twenty healthy controls (6 males/14 females, mean age 62.5 ± 2.3 years) underwent audiological and MRS examinations. Pure tone audiometry from 0.125 to 8 KHz and tympanometry were used to assess the hearing abilities of all subjects. The pure tone average (PTA; the average of hearing thresholds at 0.5, 1, 2, and 4 kHz) was calculated. The MEGA-PRESS sequence was used to measure GABA+ concentrations in 4 × 3 × 3 cm3 volumes centered on the left and right Heschl’s gyri. GABA+ concentrations were significantly lower in the presbycusis group compared to the control group (left auditory regions: p = 0.002, right auditory regions: p = 0.008). Significant negative correlations were observed between PTA and GABA+ concentrations in the presbycusis group (r = −0.57, p = 0.02), while a similar trend was found in the control group (r = −0.40, p = 0.08). These results are consistent with a hypothesis of dysfunctional GABAergic neurotransmission in the central auditory system in presbycusis, and suggest a potential treatment target for presbycusis. PMID:25463460

  16. Bridging the Gap Between Materials and Learners: Maximizing Auditory Instruction. Auditory Learning Monograph Series 5.

    ERIC Educational Resources Information Center

    Carlson, Nancy A.; And Others

    Described is a system (created by the Great Lakes Region Special Education Instructional Materials Center) for classifying auditory learners and matching them to appropriate auditory learning experiences. The learner classification system outlined utilizes an organizational table that accommodates five learner variables (mental age, chronological…

  17. Dynamics of auditory working memory

    PubMed Central

    Kaiser, Jochen

    2015-01-01

    Working memory denotes the ability to retain stimuli in mind that are no longer physically present and to perform mental operations on them. Electro- and magnetoencephalography allow investigating the short-term maintenance of acoustic stimuli at a high temporal resolution. Studies investigating working memory for non-spatial and spatial auditory information have suggested differential roles of regions along the putative auditory ventral and dorsal streams, respectively, in the processing of the different sound properties. Analyses of event-related potentials have shown sustained, memory load-dependent deflections over the retention periods. The topography of these waves suggested an involvement of modality-specific sensory storage regions. Spectral analysis has yielded information about the temporal dynamics of auditory working memory processing of individual stimuli, showing activation peaks during the delay phase whose timing was related to task performance. Coherence at different frequencies was enhanced between frontal and sensory cortex. In summary, auditory working memory seems to rely on the dynamic interplay between frontal executive systems and sensory representation regions. PMID:26029146

  18. MR Analysis of Regional Brain Volume in Adolescent Idiopathic Scoliosis: Neurological Manifestation of a Systemic Disease

    PubMed Central

    Liu, Tianming; Chu, Winnie C.W.; Young, Geoffrey; Li, Kaiming; Yeung, Benson H.Y.; Guo, Lei; Man, Gene C.W.; Lam, Wynnie W.M.; Wong, Stephen T.C.; Cheng, Jack C.Y.

    2008-01-01

    Purpose To investigate whether regional brain volumes in adolescent idiopathic scoliosis (AIS) patients differ from matched control subjects as AIS subjects are reported to have poor performance on combined visual and proprioceptive testing and impaired postural balance in previous studies. Materials and Methods Twenty AIS female patients with typical right-convex thoracic curve (age range,11−18 years; mean, 14.1 years) and 26 female controls (mean age, 14.8 years) underwent three-dimensional magnetization prepared rapid acquisition gradient echo (3D-MPRAGE) MR imaging. Volumes of 99 preselected neuroanatomical regions were compared by statistical parametric mapping and atlas-based hybrid warping. Results Analysis of variance statistics revealed significant mean volumetric differences in 22 brain regions between AIS and controls. Ten regions were larger in AIS including the left frontal gyri and white matter in left frontal, parietal, and temporal regions, corpus callosum and brainstem. Twelve regions were smaller in AIS, including right-sided descending white matter tracts (anterior and posterior limbs of the right internal capsule and the cerebral peduncle) and deep nucleus (caudate), bilateral perirhinal cortices, left hippocampus and amygdala, bilateral precuneus gyri, and left middle and inferior occipital gyri. Conclusion Regional brain volume difference in AIS subjects may help to explain neurological abnormalities in this group. PMID:18302230

  19. Peak I of the human auditory brainstem response results from the somatic regions of type I spiral ganglion cells: Evidence from computer modeling

    PubMed Central

    Rattay, Frank; Danner, Simon M.

    2014-01-01

    Early neural responses to acoustic signals can be electrically recorded as a series of waves, termed the auditory brainstem response (ABR). The latencies of the ABR waves are important for clinical and neurophysiological evaluations. Using a biophysical model of transmembrane currents along spiral ganglion cells, we show that in human (i) the non-myelinated somatic regions of type I cells, which innervate inner hair cells, predominantly contribute to peak I, (ii) the supra-strong postsynaptic stimulating current (400 pA) and transmembrane currents of the myelinated peripheral axons of type I cells are an order smaller; such postsynaptic currents correspond to the short latencies of a small recordable ABR peak I’, (iii) the ABR signal involvement of the central axon of bipolar type I cells is more effective than their peripheral counterpart as the doubled diameter causes larger transmembrane currents and a larger spike dipole-length, (iv) non-myelinated fibers of type II cells which innervate the outer hair cells generate essentially larger transmembrane currents but their ABR contribution is small because of the small ratio type II/type I cells, low firing rates and a short dipole length of spikes propagating slowly in non-myelinated fibers. Using a finite element model of a simplified head, peaks In and II (where In is the negative peak after peak I) are found to be stationary potentials when volleys of spikes cross the external electrical conductivity barrier at the bone&dura/CSF and at the CSF/brainstem interface whereas peaks I’ and I may be generated by strong local transmembrane currents as postsynaptic events at the distal ending and the soma region of type I cells, respectively. All simulated human inter-peak times (I–I′, II–I, In–I) are close to published data. PMID:25019355

  20. Mapping the Regional Influence of Genetics on Brain Structure Variability - A Tensor-Based Morphometry Study

    PubMed Central

    Brun, Caroline; Leporé, Natasha; Pennec, Xavier; Lee, Agatha D.; Barysheva, Marina; Madsen, Sarah K.; Avedissian, Christina; Chou, Yi-Yu; de Zubicaray, Greig I.; McMahon, Katie; Wright, Margaret; Toga, Arthur W.; Thompson, Paul M.

    2010-01-01

    Genetic and environmental factors influence brain structure and function profoundly The search for heritable anatomical features and their influencing genes would be accelerated with detailed 3D maps showing the degree to which brain morphometry is genetically determined. As part of an MRI study that will scan 1150 twins, we applied Tensor-Based Morphometry to compute morphometric differences in 23 pairs of identical twins and 23 pairs of same-sex fraternal twins (mean age: 23.8 ± 1.8 SD years). All 92 twins’ 3D brain MRI scans were nonlinearly registered to a common space using a Riemannian fluid-based warping approach to compute volumetric differences across subjects. A multi-template method was used to improve volume quantification. Vector fields driving each subject’s anatomy onto the common template were analyzed to create maps of local volumetric excesses and deficits relative to the standard template. Using a new structural equation modeling method, we computed the voxelwise proportion of variance in volumes attributable to additive (A) or dominant (D) genetic factors versus shared environmental (C) or unique environmental factors (E). The method was also applied to various anatomical regions of interest (ROIs). As hypothesized, the overall volumes of the brain, basal ganglia, thalamus, and each lobe were under strong genetic control; local white matter volumes were mostly controlled by common environment. After adjusting for individual differences in overall brain scale, genetic influences were still relatively high in the corpus callosum and in early-maturing brain regions such as the occipital lobes, while environmental influences were greater in frontal brain regions which have a more protracted maturational time-course. PMID:19446645

  1. Predictive coding of visual-auditory and motor-auditory events: An electrophysiological study.

    PubMed

    Stekelenburg, Jeroen J; Vroomen, Jean

    2015-11-11

    The amplitude of auditory components of the event-related potential (ERP) is attenuated when sounds are self-generated compared to externally generated sounds. This effect has been ascribed to internal forward modals predicting the sensory consequences of one's own motor actions. Auditory potentials are also attenuated when a sound is accompanied by a video of anticipatory visual motion that reliably predicts the sound. Here, we investigated whether the neural underpinnings of prediction of upcoming auditory stimuli are similar for motor-auditory (MA) and visual-auditory (VA) events using a stimulus omission paradigm. In the MA condition, a finger tap triggered the sound of a handclap whereas in the VA condition the same sound was accompanied by a video showing the handclap. In both conditions, the auditory stimulus was omitted in either 50% or 12% of the trials. These auditory omissions induced early and mid-latency ERP components (oN1 and oN2, presumably reflecting prediction and prediction error), and subsequent higher-order error evaluation processes. The oN1 and oN2 of MA and VA were alike in amplitude, topography, and neural sources despite that the origin of the prediction stems from different brain areas (motor versus visual cortex). This suggests that MA and VA predictions activate a sensory template of the sound in auditory cortex. This article is part of a Special Issue entitled SI: Prediction and Attention. PMID:25641042

  2. The oscillatory activities and its synchronization in auditory-visual integration as revealed by event-related potentials to bimodal stimuli

    NASA Astrophysics Data System (ADS)

    Guo, Jia; Xu, Peng; Yao, Li; Shu, Hua; Zhao, Xiaojie

    2012-03-01

    Neural mechanism of auditory-visual speech integration is always a hot study of multi-modal perception. The articulation conveys speech information that helps detect and disambiguate the auditory speech. As important characteristic of EEG, oscillations and its synchronization have been applied to cognition research more and more. This study analyzed the EEG data acquired by unimodal and bimodal stimuli using time frequency and phase synchrony approach, investigated the oscillatory activities and its synchrony modes behind evoked potential during auditory-visual integration, in order to reveal the inherent neural integration mechanism under these modes. It was found that beta activity and its synchronization differences had relationship with gesture N1-P2, which happened in the earlier stage of speech coding to pronouncing action. Alpha oscillation and its synchronization related with auditory N1-P2 might be mainly responsible for auditory speech process caused by anticipation from gesture to sound feature. The visual gesture changing enhanced the interaction of auditory brain regions. These results provided explanations to the power and connectivity change of event-evoked oscillatory activities which matched ERPs during auditory-visual speech integration.

  3. Neural circuits in auditory and audiovisual memory.

    PubMed

    Plakke, B; Romanski, L M

    2016-06-01

    Working memory is the ability to employ recently seen or heard stimuli and apply them to changing cognitive context. Although much is known about language processing and visual working memory, the neurobiological basis of auditory working memory is less clear. Historically, part of the problem has been the difficulty in obtaining a robust animal model to study auditory short-term memory. In recent years there has been neurophysiological and lesion studies indicating a cortical network involving both temporal and frontal cortices. Studies specifically targeting the role of the prefrontal cortex (PFC) in auditory working memory have suggested that dorsal and ventral prefrontal regions perform different roles during the processing of auditory mnemonic information, with the dorsolateral PFC performing similar functions for both auditory and visual working memory. In contrast, the ventrolateral PFC (VLPFC), which contains cells that respond robustly to auditory stimuli and that process both face and vocal stimuli may be an essential locus for both auditory and audiovisual working memory. These findings suggest a critical role for the VLPFC in the processing, integrating, and retaining of communication information. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26656069

  4. Areas activated during naturalistic reading comprehension overlap topological visual, auditory, and somatotomotor maps.

    PubMed

    Sood, Mariam R; Sereno, Martin I

    2016-08-01

    Cortical mapping techniques using fMRI have been instrumental in identifying the boundaries of topological (neighbor-preserving) maps in early sensory areas. The presence of topological maps beyond early sensory areas raises the possibility that they might play a significant role in other cognitive systems, and that topological mapping might help to delineate areas involved in higher cognitive processes. In this study, we combine surface-based visual, auditory, and somatomotor mapping methods with a naturalistic reading comprehension task in the same group of subjects to provide a qualitative and quantitative assessment of the cortical overlap between sensory-motor maps in all major sensory modalities, and reading processing regions. Our results suggest that cortical activation during naturalistic reading comprehension overlaps more extensively with topological sensory-motor maps than has been heretofore appreciated. Reading activation in regions adjacent to occipital lobe and inferior parietal lobe almost completely overlaps visual maps, whereas a significant portion of frontal activation for reading in dorsolateral and ventral prefrontal cortex overlaps both visual and auditory maps. Even classical language regions in superior temporal cortex are partially overlapped by topological visual and auditory maps. By contrast, the main overlap with somatomotor maps is restricted to a small region on the anterior bank of the central sulcus near the border between the face and hand representations of M-I. Hum Brain Mapp 37:2784-2810, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27061771

  5. Areas activated during naturalistic reading comprehension overlap topological visual, auditory, and somatotomotor maps

    PubMed Central

    2016-01-01

    Abstract Cortical mapping techniques using fMRI have been instrumental in identifying the boundaries of topological (neighbor‐preserving) maps in early sensory areas. The presence of topological maps beyond early sensory areas raises the possibility that they might play a significant role in other cognitive systems, and that topological mapping might help to delineate areas involved in higher cognitive processes. In this study, we combine surface‐based visual, auditory, and somatomotor mapping methods with a naturalistic reading comprehension task in the same group of subjects to provide a qualitative and quantitative assessment of the cortical overlap between sensory‐motor maps in all major sensory modalities, and reading processing regions. Our results suggest that cortical activation during naturalistic reading comprehension overlaps more extensively with topological sensory‐motor maps than has been heretofore appreciated. Reading activation in regions adjacent to occipital lobe and inferior parietal lobe almost completely overlaps visual maps, whereas a significant portion of frontal activation for reading in dorsolateral and ventral prefrontal cortex overlaps both visual and auditory maps. Even classical language regions in superior temporal cortex are partially overlapped by topological visual and auditory maps. By contrast, the main overlap with somatomotor maps is restricted to a small region on the anterior bank of the central sulcus near the border between the face and hand representations of M‐I. Hum Brain Mapp 37:2784–2810, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27061771

  6. Cognitive control of drug craving inhibits brain reward regions in cocaine abusers

    SciTech Connect

    Volkow, N.D.; Fowler, J.; Wang, G.J.; Telang, F.; Logan, J.; Jayne, M.; Ma, Y.; Pradhan, K.; Wong, C.T.; Swanson, J.M.

    2010-01-01

    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). Statistical 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.

  7. [Unilateral auditory hallucinations due to left temporal lobe ischemia: a case report].

    PubMed

    Anegawa, T; Hara, K; Yamamoto, K; Matsuda, M

    1995-10-01

    . The Wechsler adult intelligence scale revealed a verbal IQ of 91 and a performance IQ of 100. Pure tone audiometry revealed bilateral, mild peripheral sensorineural hearing loss. Brainstem auditory evoked potentials were unrevealing. The EEG showed slow activities in the left temporoparietal region. Magnetic resonance imaging of the brain failed to reveal any relevant abnormalities except for an old hemorrhagic parietal infarct. The SPECT with Tc99m-HMPAO, however, showed reduced blood flow in the left temporal lobe including the first temporal convolution as well as in the left parietal lobe. Based on the SPECT findings, unilateral auditory hallucinations in our patient are considered to have resulted from the left temporal lobe ischemia. Our case indicates that unilateral auditory hallucinations may have a clinicoanatomical correlation with contralateral temporal lobe lesions. PMID:8821499

  8. Auditory Imagery: Empirical Findings

    ERIC Educational Resources Information Center

    Hubbard, Timothy L.

    2010-01-01

    The empirical literature on auditory imagery is reviewed. Data on (a) imagery for auditory features (pitch, timbre, loudness), (b) imagery for complex nonverbal auditory stimuli (musical contour, melody, harmony, tempo, notational audiation, environmental sounds), (c) imagery for verbal stimuli (speech, text, in dreams, interior monologue), (d)…

  9. Functional Connectivity between Brain Regions Involved in Learning Words of a New Language

    ERIC Educational Resources Information Center

    Veroude, Kim; Norris, David G.; Shumskaya, Elena; Gullberg, Marianne; Indefrey, Peter

    2010-01-01

    Previous studies have identified several brain regions that appear to be involved in the acquisition of novel word forms. Standard word-by-word presentation is often used although exposure to a new language normally occurs in a natural, real world situation. In the current experiment we investigated naturalistic language exposure and applied a…

  10. 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), cereb...

  11. Differential effects of age and history of hypertension on regional brain volumes and iron

    PubMed Central

    Rodrigue, Karen M.; Haacke, E. Mark; Raz, Naftali

    2010-01-01

    Aging affects various structural and metabolic properties of the brain. However, associations among various aspects of brain aging are unclear. Moreover, those properties and associations among them may be modified by age-associated increase in vascular risk. In this study, we measured volume of brain regions that vary in their vulnerability to aging and estimated local iron content via T2* relaxometry. In 113 healthy adults (19–83 years old), we examined prefrontal cortex (PFC), primary visual cortex (VC), hippocampus (HC), entorhinal cortex (EC), caudate nucleus (Cd), and putamen (Pt). In some regions (PFC, VC, Cd, Pt) age-related differences in iron and volume followed similar patterns. However, in the medial temporal structures, volume and iron content exhibited different age trajectories. Whereas age-related volume reduction was mild in HC and absent in EC, iron content evidenced significant age-related declines. In hypertensive participants significantly greater iron content was noted in all examined regions. Thus, iron content as measured by T2* may be a sensitive index of regional brain aging and may reveal declines that are more prominent than gross anatomical shrinkage. PMID:20923707

  12. Delineation of separate brain regions used for scientific versus engineering modes of thinking

    NASA Astrophysics Data System (ADS)

    Patterson, Clair C.

    1994-08-01

    Powerful, latent abilities for extreme sophistication in abstract rationalization as potential biological adaptive behavioral responses were installed entirely through accident and inadvertence by biological evolution in the Homo sapiens sapiens species of brain. These potentials were never used, either in precursor species as factors in evolutionary increase in hominid brain mass, nor in less sophisticated forms within social environments characterized by Hss tribal brain population densities. Those latent abilities for unnatural biological adaptive behavior were forced to become manifest in various ways by growths in sophistication of communication interactions engendered by large growths in brain population densities brought on by developments in agriculture at the onset of the Holocene. It is proposed that differences probably exist between regions of the Hss brain involved in utilitarian, engineering types of problem conceptualization-solving versus regions of the brain involved in nonutilitarian, artistic-scientific types of problem conceptualization-solving. Populations isolated on separate continents from diffusive contact and influence on cultural developments, and selected for comparison of developments during equivalent stages of technological and social sophistication in matching 4000 year periods, show, at the ends of those periods, marked differences in aesthetic attributes expressed in cosmogonies, music, and writing (nonutilitarian thinking related to science and art). On the other hand the two cultures show virtually identical developments in three major stages of metallurgical technologies (utilitarian thinking related to engineering). Such archaeological data suggest that utilitarian modes of thought may utilize combinations of neuronal circuits in brain regions that are conserved among tribal populations territorially separated from each other for tens of thousands of years. Such conservation may not be true for neuronal circuits involved in

  13. Auditory Training for Central Auditory Processing Disorder.

    PubMed

    Weihing, Jeffrey; Chermak, Gail D; Musiek, Frank E

    2015-11-01

    Auditory training (AT) is an important component of rehabilitation for patients with central auditory processing disorder (CAPD). The present article identifies and describes aspects of AT as they relate to applications in this population. A description of the types of auditory processes along with information on relevant AT protocols that can be used to address these specific deficits is included. Characteristics and principles of effective AT procedures also are detailed in light of research that reflects on their value. Finally, research investigating AT in populations who show CAPD or present with auditory complaints is reported. Although efficacy data in this area are still emerging, current findings support the use of AT for treatment of auditory difficulties. PMID:27587909

  14. The human auditory evoked response

    NASA Technical Reports Server (NTRS)

    Galambos, R.

    1974-01-01

    Figures are presented of computer-averaged auditory evoked responses (AERs) that point to the existence of a completely endogenous brain event. A series of regular clicks or tones was administered to the ear, and 'odd-balls' of different intensity or frequency respectively were included. Subjects were asked either to ignore the sounds (to read or do something else) or to attend to the stimuli. When they listened and counted the odd-balls, a P3 wave occurred at 300msec after stimulus. When the odd-balls consisted of omitted clicks or tone bursts, a similar response was observed. This could not have come from auditory nerve, but only from cortex. It is evidence of recognition, a conscious process.

  15. Regional Differences in the Neuronal Expression of Cyclooxygenase-2 (COX-2) in the Newborn Pig Brain

    PubMed Central

    Oláh, Orsolya; Németh, István; Tóth-Szűki, Valéria; Bari, Ferenc; Domoki, Ferenc

    2012-01-01

    Cyclooxygenase (COX)-2 is the major constitutively expressed COX isoform in the newborn brain. COX-2 derived prostanoids and reactive oxygen species appear to play a major role in the mechanism of perinatal hypoxic-ischemic injury in the newborn piglet, an accepted animal model of the human term neonate. The study aimed to quantitatively determine COX-2 immunopositive neurons in different brain regions in piglets under normoxic conditions (n=15), and 4 hours after 10 min asphyxia (n=11). Asphyxia did not induce significant changes in neuronal COX-2 expression of any studied brain areas. In contrast, there was a marked regional difference in all experimental groups. Thus, significant difference was observed between fronto-parietal and temporo-occipital regions: 59±4% and 67±3% versus 41±2%* and 31±3%* respectively (mean±SEM, data are pooled from all subjects, n=26, *p<0.05, vs. fronto-parietal region). In the hippocampus, COX-2 immunopositivity was rare (highest expression in CA1 region: 14±2%). The studied subcortical areas showed negligible COX-2 staining. Our findings suggest that asphyxia does not significantly alter the pattern of neuronal COX-2 expression in the early reventilation period. Furthermore, based on the striking differences observed in cortical neuronal COX-2 distribution, the contribution of COX-2 mediated neuronal injury after asphyxia may also show region-specific differences. PMID:22829712

  16. Preserved pontine glucose metabolism in Alzheimer disease: A reference region for functional brain image (PET) analysis

    SciTech Connect

    Minoshima, Satoshi; Frey, K.A.; Foster, N.L.; Kuhl, D.W.

    1995-07-01

    Our goal was to examine regional preservation of energy metabolism in Alzheimer disease (AD) and to evaluate effects of PET data normalization to reference regions. Regional metabolic rates in the pons, thalamus, putamen, sensorimotor cortex, visual cortex, and cerebellum (reference regions) were determined stereotaxically and examined in 37 patients with probable AD and 22 normal controls based on quantitative {sup 18}FDG-PET measurements. Following normalization of metabolic rates of the parietotemporal association cortex and whole brain to each reference region, distinctions of the two groups were assessed. The pons showed the best preservation of glucose metabolism in AD. Other reference regions showed relatively preserved metabolism compared with the parietotemporal association cortex and whole brain, but had significant metabolic reduction. Data normalization to the pons not only enhanced statistical significance of metabolic reduction in the parietotemporal association cortex, but also preserved the presence of global cerebral metabolic reduction indicated in analysis of the quantitative data. Energy metabolism in the pons in probable AD is well preserved. The pons is a reliable reference for data normalization and will enhance diagnostic accuracy and efficiency of quantitative and nonquantitative functional brain imaging. 39 refs., 2 figs., 3 tabs.

  17. Regional distribution of potassium, calcium, and six trace elements in normal human brain

    SciTech Connect

    Duflou, H.; Maenhaut, W.; De Reuck, J. )

    1989-11-01

    Eight elements (i.e. K, Ca, Mn, Fe, Cu, Zn, Se, and Rb) were measured in 50 different regions of 12 normal human brains by particle-induced X-ray emission (PIXE) analysis. The dry weight concentrations of K, Fe, Cu, Zn, Se, and Rb were consistently higher for gray than for white matter areas. The K, Zn and Se concentrations for the regions of mixed composition and, to some extent, also the Rb concentrations, were intermediate between the gray and white matter values, and they tended to decrease with decreasing neuron density. The mean dry weight concentrations of K, Ca, Zn, Se, and Rb in the various brain regions were highly correlated with the mean wet-to-dry weight ratios of these regions. For Mn, Fe, and Cu, however, such a correlation was not observed, and these elements exhibited elevated levels in several structures of the basal ganglia. For K, Fe, and Se the concentrations seemed to change with age. A hierarchical cluster analysis indicated that the structures clustered into two large groups, one comprising gray and mixed matter regions, the other white and mixed matter areas. Brain structures involved in the same physiological function or morphologically similar regions often conglomerated in a single subcluster.

  18. Electrophysiological measurement of human auditory function

    NASA Technical Reports Server (NTRS)

    Galambos, R.

    1975-01-01

    Knowledge of the human auditory evoked response is reviewed, including methods of determining this response, the way particular changes in the stimulus are coupled to specific changes in the response, and how the state of mind of the listener will influence the response. Important practical applications of this basic knowledge are discussed. Measurement of the brainstem evoked response, for instance, can state unequivocally how well the peripheral auditory apparatus functions. It might then be developed into a useful hearing test, especially for infants and preverbal or nonverbal children. Clinical applications of measuring the brain waves evoked 100 msec and later after the auditory stimulus are undetermined. These waves are clearly related to brain events associated with cognitive processing of acoustic signals, since their properties depend upon where the listener directs his attention and whether how long he expects the signal.

  19. Adolescent binge ethanol treatment alters adult brain regional volumes, cortical extracellular matrix protein and behavioral flexibility

    PubMed Central

    Coleman, Leon Garland; Liu, Wen; Oguz, Ipek; Styner, Martin; Crews, Fulton T.

    2014-01-01

    Adolescents binge drink more than any other age group, increasing risk of disrupting the development of the frontal cortex. We hypothesized that adolescent binge drinking would lead to persistent alterations in adulthood. In this study, we modeled adolescent weekend underage binge-drinking, using adolescent mice (post-natal days [P] 28–37). The adolescent intermittent binge ethanol (AIE) treatment includes 6 binge intragastric doses of ethanol in an intermittent pattern across adolescence. Assessments were conducted in adulthood following extended abstinence to determine if there were persistent changes in adults. Reversal learning, open field and other behavioral assessments as well as brain structure using magnetic imaging and immunohistochemistry were determined. We found AIE did not impact adult Barnes Maze learning. However, AIE did cause reversal learning deficits in adults. AIE also caused structural changes in the adult brain. AIE was associated with adulthood volume enlargements in specific brain regions without changes in total brain volume. Enlarged regions included the orbitofrontal cortex (OFC, 4%), cerebellum (4.5%), thalamus (2%), internal capsule (10%) and genu of the corpus callosum (7%). The enlarged OFC volume in adults after AIE is consistent with previous imaging studies in human adolescents. AIE treatment was associated with significant increases in the expression of several extracellular matrix (ECM) proteins in the adult OFC including WFA (55%), Brevican (32%), Neurocan (105%), Tenacin-C (25%), and HABP (5%). These findings are consistent with AIE causing persistent changes in brain structure that could contribute to a lack of behavioral flexibility. PMID:24275185

  20. Sharing self-related information is associated with intrinsic functional connectivity of cortical midline brain regions.

    PubMed

    Meshi, Dar; Mamerow, Loreen; Kirilina, Evgeniya; Morawetz, Carmen; Margulies, Daniel S; Heekeren, Hauke R

    2016-01-01

    Human beings are social animals and they vary in the degree to which they share information about themselves with others. Although brain networks involved in self-related cognition have been identified, especially via the use of resting-state experiments, the neural circuitry underlying individual differences in the sharing of self-related information is currently unknown. Therefore, we investigated the intrinsic functional organization of the brain with respect to participants' degree of self-related information sharing using resting state functional magnetic resonance imaging and self-reported social media use. We conducted seed-based correlation analyses in cortical midline regions previously shown in meta-analyses to be involved in self-referential cognition: the medial prefrontal cortex (MPFC), central precuneus (CP), and caudal anterior cingulate cortex (CACC). We examined whether and how functional connectivity between these regions and the rest of the brain was associated with participants' degree of self-related information sharing. Analyses revealed associations between the MPFC and right dorsolateral prefrontal cortex (DLPFC), as well as the CP with the right DLPFC, the left lateral orbitofrontal cortex and left anterior temporal pole. These findings extend our present knowledge of functional brain connectivity, specifically demonstrating how the brain's intrinsic functional organization relates to individual differences in the sharing of self-related information. PMID:26948055

  1. REGIONAL BRAIN VOLUME REDUCTIONS RELATE TO FACIAL DYSMORPHOLOGY AND NEUROCOGNITIVE FUNCTION IN FETAL ALCOHOL SPECTRUM DISORDERS

    PubMed Central

    Roussotte, Florence F.; Sulik, Kathleen K.; Mattson, Sarah N.; Riley, Edward P.; Jones, Kenneth L.; Adnams, Colleen M.; May, Philip A.; O’Connor, Mary J.; Narr, Katherine L.; Sowell, Elizabeth R.

    2013-01-01

    Individuals with heavy prenatal alcohol exposure can experience significant deficits in cognitive and psychosocial functioning and alterations in brain structure that persist into adulthood. In this report, data from 99 participants collected across three sites (Los Angeles and San Diego, California, and Cape Town, South Africa) were analyzed to examine relationships between brain structure, neurocognitive function, facial morphology, and maternal reports of quantities of alcohol consumption during the first trimester. Across study sites, we found highly significant volume reductions in the FASD group for all of the brain regions evaluated. After correcting for scan location, age, and total brain volume, these differences remained significant in some regions of the basal ganglia and diencephalon. In alcohol-exposed subjects, we found that smaller palpebral fissures were significantly associated with reduced volumes in the diencephalon bilaterally, that greater dysmorphology of the philtrum predicted smaller volumes in basal ganglia and diencephalic structures, and that lower IQ scores were associated with both smaller basal ganglia volumes and greater facial dysmorphology. In subjects from South Africa, we found a significant negative correlation between intracranial volume and total number of drinks per week in the first trimester. These results corroborate previous reports that prenatal alcohol exposure is particularly toxic to basal ganglia and diencephalic structures. We extend previous findings by illustrating relationships between specific measures of facial dysmorphology and the volumes of particular subcortical structures, and for the first time show that continuous measures of maternal alcohol consumption during the first trimester relates to overall brain volume reduction. PMID:21416562

  2. Brain regions essential for improved lexical access in an aged aphasic patient: a case report

    PubMed Central

    Meinzer, Marcus; Flaisch, Tobias; Obleser, Jonas; Assadollahi, Ramin; Djundja, Daniela; Barthel, Gabriela; Rockstroh, Brigitte

    2006-01-01

    Background The relationship between functional recovery after brain injury and concomitant neuroplastic changes is emphasized in recent research. In the present study we aimed to delineate brain regions essential for language performance in aphasia using functional magnetic resonance imaging and acquisition in a temporal sparse sampling procedure, which allows monitoring of overt verbal responses during scanning. Case presentation An 80-year old patient with chronic aphasia (2 years post-onset) was investigated before and after intensive language training using an overt picture naming task. Differential brain activation in the right inferior frontal gyrus for correct word retrieval and errors was found. Improved language performance following therapy was mirrored by increased fronto-thalamic activation while stability in more general measures of attention/concentration and working memory was assured. Three healthy age-matched control subjects did not show behavioral changes or increased activation when tested repeatedly within the same 2-week time interval. Conclusion The results bear significance in that the changes in brain activation reported can unequivocally be attributed to the short-term training program and a language domain-specific plasticity process. Moreover, it further challenges the claim of a limited recovery potential in chronic aphasia, even at very old age. Delineation of brain regions essential for performance on a single case basis might have major implications for treatment using transcranial magnetic stimulation. PMID:16916464

  3. Changes in multiple brain regions underlie species differences in a complex, congenital behavior

    PubMed Central

    Balaban, Evan

    1997-01-01

    The evolutionary brain modifications that produce any complex, congenital behavioral difference between two species have never been identified. Evolutionary processes may (i) alter a single, “higher” brain area that generates and/or coordinates the diverse motor components of a complex act; (ii) separately change independent, “lower” brain areas that modulate the fine motor control of the individual components; or (iii) modify both types of areas. This study explores the brain localization of a species difference in one such behavior, the crowing of chickens (Gallus gallus domesticus) and Japanese quail (Coturnix coturnix japonica). Two major subcomponents of the behavioral difference can be independently transferred with interspecies transplantation of separate brain regions, despite the fact that these components, sound and patterned head movement, occur together in a highly integrated fashion. To our knowledge, this is the first experimental demonstration that species differences in a complex behavior are built up from separate changes to distinct cell groups in different parts of the brain and that these cell groups have independent effects on individual behavioral components. PMID:9050894

  4. Regional brain glucose use in unstressed rats after two days of starvation

    SciTech Connect

    Mans, A.M.; Davis, D.W.; Hawkins, R.A.

    1987-12-01

    Regional brain glucose use was measured in conscious, unrestrained, fed rats and after 2 days of starvation, using quantitative autoradiography and (6-/sup 14/C)glucose. Plasma glucose, lactate, and ketone body concentrations and brain glucose and lactate content were measured in separate groups of rats. Glucose concentrations were lower in starved rats in both plasma and brain; plasma ketone body concentrations were elevated. Glucose use was found to be lower throughout the brain by about 12%. While some areas seemed to be affected more than others, statistical analysis showed that none were exceptionally different. The results could not be explained by increased loss of /sup 14/C as lactate or pyruvate during the experimental period, because the arteriovenous differences of these species were insignificant. The calculated contribution by ketone bodies to the total energy consumption was between 3 and 9% for the brain as a whole in the starved rats and could, therefore, partially account for the depression seen in glucose use. It was concluded that glucose oxidation is slightly depressed throughout the brain after 2 days of starvation.

  5. Evidence from cyclostomes for complex regionalization of the ancestral vertebrate brain.

    PubMed

    Sugahara, Fumiaki; Pascual-Anaya, Juan; Oisi, Yasuhiro; Kuraku, Shigehiro; Aota, Shin-ichi; Adachi, Noritaka; Takagi, Wataru; Hirai, Tamami; Sato, Noboru; Murakami, Yasunori; Kuratani, Shigeru

    2016-03-01

    The vertebrate brain is highly complex, but its evolutionary origin remains elusive. Because of the absence of certain developmental domains generally marked by the expression of regulatory genes, the embryonic brain of the lamprey, a jawless vertebrate, had been regarded as representing a less complex, ancestral state of the vertebrate brain. Specifically, the absence of a Hedgehog- and Nkx2.1-positive domain in the lamprey subpallium was thought to be similar to mouse mutants in which the suppression of Nkx2-1 leads to a loss of the medial ganglionic eminence. Here we show that the brain of the inshore hagfish (Eptatretus burgeri), another cyclostome group, develops domains equivalent to the medial ganglionic eminence and rhombic lip, resembling the gnathostome brain. Moreover, further investigation of lamprey larvae revealed that these domains are also present, ruling out the possibility of convergent evolution between hagfish and gnathostomes. Thus, brain regionalization as seen in crown gnathostomes is not an evolutionary innovation of this group, but dates back to the latest vertebrate ancestor before the divergence of cyclostomes and gnathostomes more than 500 million years ago. PMID:26878236

  6. Regional brain uptake and retention of Tc-99m-propylene amine oxime derivatives

    SciTech Connect

    Chaplin, S.B.; Oberle, P.O.; Hoffman, T.J.; Volkert, W.A.; Holmes, R.A.; Nowotnik, D.P.; Pickett, R.D.; Neirinckx, R.

    1985-05-01

    Tc-99m-propylene amine oxime (Tc-99m-PnAO) is a neutral lipophilic chelate that rapidly and passively enters the cerebral cortex (80% on first pass in baboon brain) and then clears exponentially leaving inadequate activity to perform conventional SPECT brain imaging. When side chains are attached to the PnAO backbone lipophilicity is increased, as well as brain retention. In this work the authors evaluated regional brain uptake and retention of Tc-99m-PnAO and several of its derivatives in rat brain using serial autoradiography (ARG). Autoradiographs of each Tc-99m chelate at 5 sec. post peak brain uptake demonstrate discrete grey to white matter differentiation. White matter tracts are well delineated and the darker areas of grey matter appearing in the midbrain and thalamus, corresponding to areas of high capillary density and high blood flow documented with C-14-iodoantipyrine, are easily distinguished. Within 5 min. of the peak uptake the regional uptake and grey/white differentiation is lost on the Tc-99m-PnAO ARG. In contrast the 5 min. ARG of the more lipophilic Tc-99m, chelate with dimethyl-PnAO (DMPnAO) shows the complete reverse of the 5 sec. ARG, with greater activity in the white matter tracts than in the grey matter. One of the derivatives, tetramethyl-PAO (TMPAO) complexed with Tc-99m is retained in the grey matter of rat brain and shows persistent grey to white localization for at least 60 min., analogous to what has been reported with I-123-IMP. These results suggest that Tc-99m-TMPAO or one of its derivatives may be appropriate for SPECT imaging of cerebral blood flow abnormalities.

  7. Identification of Differentially Expressed Genes through Integrated Study of Alzheimer’s Disease Affected Brain Regions

    PubMed Central

    Berretta, Regina; Moscato, Pablo

    2016-01-01

    Background Alzheimer’s disease (AD) is the most common form of dementia in older adults that damages the brain and results in impaired memory, thinking and behaviour. The identification of differentially expressed genes and related pathways among affected brain regions can provide more information on the mechanisms of AD. In the past decade, several studies have reported many genes that are associated with AD. This wealth of information has become difficult to follow and interpret as most of the results are conflicting. In that case, it is worth doing an integrated study of multiple datasets that helps to increase the total number of samples and the statistical power in detecting biomarkers. In this study, we present an integrated analysis of five different brain region datasets and introduce new genes that warrant further investigation. Methods The aim of our study is to apply a novel combinatorial optimisation based meta-analysis approach to identify differentially expressed genes that are associated to AD across brain regions. In this study, microarray gene expression data from 161 samples (74 non-demented controls, 87 AD) from the Entorhinal Cortex (EC), Hippocampus (HIP), Middle temporal gyrus (MTG), Posterior cingulate cortex (PC), Superior frontal gyrus (SFG) and visual cortex (VCX) brain regions were integrated and analysed using our method. The results are then compared to two popular meta-analysis methods, RankProd and GeneMeta, and to what can be obtained by analysing the individual datasets. Results We find genes related with AD that are consistent with existing studies, and new candidate genes not previously related with AD. Our study confirms the up-regualtion of INFAR2 and PTMA along with the down regulation of GPHN, RAB2A, PSMD14 and FGF. Novel genes PSMB2, WNK1, RPL15, SEMA4C, RWDD2A and LARGE are found to be differentially expressed across all brain regions. Further investigation on these genes may provide new insights into the development of AD

  8. Brain regional distribution of GABAA receptors exhibiting atypical GABA agonism: roles of receptor subunits

    PubMed Central

    Halonen, Lauri M.; Sinkkonen, Saku T.; Chandra, Dev; Homanics, Gregg E.; Korpi, Esa R.

    2009-01-01

    The major inhibitory neurotransmitter in the brain, γ-aminobutyric acid (GABA), has only partial efficacy at certain subtypes of GABAA receptors. To characterize these minor receptor populations in rat and mouse brains, we used autoradiographic imaging of t-butylbicyclophosphoro[35S]thionate ([35S]TBPS) binding to GABAA receptors in brain sections and compared the displacing capacities of 10 mM GABA and 1 mM 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), a competitive GABA-site agonist. Brains from GABAA receptor α1, α4, δ, and α4 + δ subunit knockout (KO) mouse lines were used to understand the contribution of these particular receptor subunits to “GABA-insensitive” (GIS) [35S]TBPS binding. THIP displaced more [35S]TBPS binding than GABA in several brain regions, indicating that THIP also inhibited GIS-binding. In these regions, GABA prevented the effect of THIP on GIS-binding. GIS-binding was increased in the cerebellar granule cell layer of δ KO and α4 + δ KO mice, being only slightly diminished in that of α1 KO mice. In the thalamus and some other forebrain regions of wild-type mice, a significant amount of GIS-binding was detected. This GIS-binding was higher in α4 KO mice. However, it was fully abolished in α1 KO mice, indicating that the α1 subunit was obligatory for the GIS-binding in the forebrain. Our results suggest that native GABAA receptors in brain sections showing reduced displacing capacity of [35S]TBPS binding by GABA (partial agonism) minimally require the assembly of α1 and β subunits in the forebrain and of α6 and β subunits in the cerebellar granule cell layer. These receptors may function as extrasynaptic GABAA receptors. PMID:19397945

  9. Brain regional distribution of GABA(A) receptors exhibiting atypical GABA agonism: roles of receptor subunits.

    PubMed

    Halonen, Lauri M; Sinkkonen, Saku T; Chandra, Dev; Homanics, Gregg E; Korpi, Esa R

    2009-11-01

    The major inhibitory neurotransmitter in the brain, gamma-aminobutyric acid (GABA), has only partial efficacy at certain subtypes of GABA(A) receptors. To characterize these minor receptor populations in rat and mouse brains, we used autoradiographic imaging of t-butylbicyclophosphoro[(35)S]thionate ([(35)S]TBPS) binding to GABA(A) receptors in brain sections and compared the displacing capacities of 10mM GABA and 1mM 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), a competitive GABA-site agonist. Brains from GABA(A) receptor alpha1, alpha4, delta, and alpha4+delta subunit knockout (KO) mouse lines were used to understand the contribution of these particular receptor subunits to "GABA-insensitive" (GIS) [(35)S]TBPS binding. THIP displaced more [(35)S]TBPS binding than GABA in several brain regions, indicating that THIP also inhibited GIS-binding. In these regions, GABA prevented the effect of THIP on GIS-binding. GIS-binding was increased in the cerebellar granule cell layer of delta KO and alpha4+delta KO mice, being only slightly diminished in that of alpha1 KO mice. In the thalamus and some other forebrain regions of wild-type mice, a significant amount of GIS-binding was detected. This GIS-binding was higher in alpha4 KO mice. However, it was fully abolished in alpha1 KO mice, indicating that the alpha1 subunit was obligatory for the GIS-binding in the forebrain. Our results suggest that native GABA(A) receptors in brain sections showing reduced displacing capacity of [(35)S]TBPS binding by GABA (partial agonism) minimally require the assembly of alpha1 and beta subunits in the forebrain and of alpha6 and beta subunits in the cerebellar granule cell layer. These receptors may function as extrasynaptic GABA(A) receptors. PMID:19397945

  10. Cranial Morphology of the Late Oligocene Patagonian Notohippid Rhynchippus equinus Ameghino, 1897 (Mammalia, Notoungulata) with Emphases in Basicranial and Auditory Region.

    PubMed

    Martínez, Gastón; Dozo, María Teresa; Gelfo, Javier N; Marani, Hernán

    2016-01-01

    "Notohippidae" is a probably paraphyletic family of medium sized notoungulates with complete dentition and early tendency to hypsodonty. They have been recorded from early Eocene to early Miocene, being particularly diverse by the late Oligocene. Although Rhynchippus equinus Ameghino is one of the most frequent notohippids in the fossil record, there are scarce data about cranial osteology other than the classical descriptions which date back to the early last century. In this context, we describe the exceptionally preserved specimen MPEF PV 695 (based on CT scanning technique and 3D reconstruction) with the aim of improving our knowledge of the species, especially regarding auditory region (petrosal, tympanic and surrounding elements), sphenoidal and occipital complexes. Besides a modular description of the whole skull, osteological correlates identified on the basicranium are used to infer some soft-tissue elements, especially those associated with vessels that supply the head, mainly intracranially. One of the most informative elements was the petrosal bone, whose general morphology matches that expected for a toxodont. The endocranial surface, together with the surrounding parietal, basisphenoid, occipital, and squamosal, enabled us to propose the location and communication of main venous sinuses of the lateral head wall (temporal, inferior and sigmoid sinuses), whereas the tympanic aspect and the identification of a posterior carotid artery canal provided strong evidence in support of an intratympanic course of the internal carotid artery, a controversial issue among notoungulates. Regarding the arrangement of tympanic and paratympanic spaces, the preservation of the specimen allowed us to appreciate the three connected spaces that constitute a heavily pneumatized middle ear; the epitympanic sinus, the tympanic cavity itself, and the ventral expansion of the tympanic cavity through the notably inflated bullae. We hope this study stimulates further inquires and

  11. Cranial Morphology of the Late Oligocene Patagonian Notohippid Rhynchippus equinus Ameghino, 1897 (Mammalia, Notoungulata) with Emphases in Basicranial and Auditory Region

    PubMed Central

    Martínez, Gastón; Dozo, María Teresa; Gelfo, Javier N.; Marani, Hernán

    2016-01-01

    “Notohippidae” is a probably paraphyletic family of medium sized notoungulates with complete dentition and early tendency to hypsodonty. They have been recorded from early Eocene to early Miocene, being particularly diverse by the late Oligocene. Although Rhynchippus equinus Ameghino is one of the most frequent notohippids in the fossil record, there are scarce data about cranial osteology other than the classical descriptions which date back to the early last century. In this context, we describe the exceptionally preserved specimen MPEF PV 695 (based on CT scanning technique and 3D reconstruction) with the aim of improving our knowledge of the species, especially regarding auditory region (petrosal, tympanic and surrounding elements), sphenoidal and occipital complexes. Besides a modular description of the whole skull, osteological correlates identified on the basicranium are used to infer some soft-tissue elements, especially those associated with vessels that supply the head, mainly intracranially. One of the most informative elements was the petrosal bone, whose general morphology matches that expected for a toxodont. The endocranial surface, together with the surrounding parietal, basisphenoid, occipital, and squamosal, enabled us to propose the location and communication of main venous sinuses of the lateral head wall (temporal, inferior and sigmoid sinuses), whereas the tympanic aspect and the identification of a posterior carotid artery canal provided strong evidence in support of an intratympanic course of the internal carotid artery, a controversial issue among notoungulates. Regarding the arrangement of tympanic and paratympanic spaces, the preservation of the specimen allowed us to appreciate the three connected spaces that constitute a heavily pneumatized middle ear; the epitympanic sinus, the tympanic cavity itself, and the ventral expansion of the tympanic cavity through the notably inflated bullae. We hope this study stimulates further inquires

  12. The evolutionary neuroscience of musical beat perception: the Action Simulation for Auditory Prediction (ASAP) hypothesis

    PubMed Central

    Patel, Aniruddh D.; Iversen, John R.

    2013-01-01

    Every human culture has some form of music with a beat: a perceived periodic pulse that structures the perception of musical rhythm and which serves as a framework for synchronized movement to music. What are the neural mechanisms of musical beat perception, and how did they evolve? One view, which dates back to Darwin and implicitly informs some current models of beat perception, is that the relevant neural mechanisms are relatively general and are widespread among animal species. On the basis of recent neural and cross-species data on musical beat processing, this paper argues for a different view. Here we argue that beat perception is a complex brain function involving temporally-precise communication between auditory regions and motor planning regions of the cortex (even in the absence of overt movement). More specifically, we propose that simulation of periodic movement in motor planning regions provides a neural signal that helps the auditory system predict the timing of upcoming beats. This “action simulation for auditory prediction” (ASAP) hypothesis leads to testable predictions. We further suggest that ASAP relies on dorsal auditory pathway connections between auditory regions and motor planning regions via the parietal cortex, and suggest that these connections may be stronger in humans than in non-human primates due to the evolution of vocal learning in our lineage. This suggestion motivates cross-species research to determine which species are capable of human-like beat perception, i.e., beat perception that involves accurate temporal prediction of beat times across a fairly broad range of tempi. PMID:24860439

  13. Repeated verum but not placebo acupuncture normalizes connectivity in brain regions dysregulated in chronic pain

    PubMed Central

    Egorova, Natalia; Gollub, Randy L.; Kong, Jian

    2015-01-01

    Acupuncture, an ancient East Asian therapy, is aimed at rectifying the imbalance within the body caused by disease. Studies evaluating the efficacy of acupuncture with neuroimaging tend to concentrate on brain regions within the pain matrix, associated with acute pain. We, however, focused on the effect of repeated acupuncture treatment specifically on brain regions known to support functions dysregulated in chronic pain disorders. Transition to chronic pain is associated with increased attention to pain, emotional rumination, nociceptive memory and avoidance learning, resulting in brain connectivity changes, specifically affecting the periaqueductal gray (PAG), medial frontal cortex (MFC) and bilateral hippocampus (Hpc). We demonstrate that the PAG–MFC and PAG–Hpc connectivity in patients with chronic pain due to knee osteoarthritis indeed correlates with clinical severity scores and further show that verum acupuncture-induced improvement in pain scores (compared to sham) is related to the modulation of PAG–MFC and PAG–Hpc connectivity in the predicted direction. This study shows that repeated verum acupuncture might act by restoring the balance in the connectivity of the key pain brain regions, altering pain-related attention and memory. PMID:26594625

  14. Repeated verum but not placebo acupuncture normalizes connectivity in brain regions dysregulated in chronic pain.

    PubMed

    Egorova, Natalia; Gollub, Randy L; Kong, Jian

    2015-01-01

    Acupuncture, an ancient East Asian therapy, is aimed at rectifying the imbalance within the body caused by disease. Studies evaluating the efficacy of acupuncture with neuroimaging tend to concentrate on brain regions within the pain matrix, associated with acute pain. We, however, focused on the effect of repeated acupuncture treatment specifically on brain regions known to support functions dysregulated in chronic pain disorders. Transition to chronic pain is associated with increased attention to pain, emotional rumination, nociceptive memory and avoidance learning, resulting in brain connectivity changes, specifically affecting the periaqueductal gray (PAG), medial frontal cortex (MFC) and bilateral hippocampus (Hpc). We demonstrate that the PAG-MFC and PAG-Hpc connectivity in patients with chronic pain due to knee osteoarthritis indeed correlates with clinical severity scores and further show that verum acupuncture-induced improvement in pain scores (compared to sham) is related to the modulation of PAG-MFC and PAG-Hpc connectivity in the predicted direction. This study shows that repeated verum acupuncture might act by restoring the balance in the connectivity of the key pain brain regions, altering pain-related attention and memory. PMID:26594625

  15. Theory of Mind Performance in Children Correlates with Functional Specialization of a Brain Region for Thinking about Thoughts

    ERIC Educational Resources Information Center

    Gweon, Hyowon; Dodell-Feder, David; Bedny, Marina; Saxe, Rebecca

    2012-01-01

    Thinking about other people's thoughts recruits a specific group of brain regions, including the temporo-parietal junctions (TPJ), precuneus (PC), and medial prefrontal cortex (MPFC). The same brain regions were recruited when children (N = 20, 5-11 years) and adults (N = 8) listened to descriptions of characters' mental states, compared to…

  16. Aberrant Global and Regional Topological Organization of the Fractional Anisotropy-weighted Brain Structural Networks in Major Depressive Disorder

    PubMed Central

    Chen, Jian-Huai; Yao, Zhi-Jian; Qin, Jiao-Long; Yan, Rui; Hua, Ling-Ling; Lu, Qing

    2016-01-01

    Background: Most previous neuroimaging studies have focused on the structural and functional abnormalities of local brain regions in major depressive disorder (MDD). Moreover, the exactly topological organization of networks underlying MDD remains unclear. This study examined the aberrant global and regional topological patterns of the brain white matter networks in MDD patients. Methods: The diffusion tensor imaging data were obtained from 27 patients with MDD and 40 healthy controls. The brain fractional anisotropy-weighted structural networks were constructed, and the global network and regional nodal metrics of the networks were explored by the complex network theory. Results: Compared with the healthy controls, the brain structural network of MDD patients showed an intact small-world topology, but significantly abnormal global network topological organization and regional nodal characteristic of the network in MDD were found. Our findings also indicated that the brain structural networks in MDD patients become a less strongly integrated network with a reduced central role of some key brain regions. Conclusions: All these resulted in a less optimal topological organization of networks underlying MDD patients, including an impaired capability of local information processing, reduced centrality of some brain regions and limited capacity to integrate information across different regions. Thus, these global network and regional node-level aberrations might contribute to understanding the pathogenesis of MDD from the view of the brain network. PMID:26960371

  17. Regional Variations in Brain Gyrification Are Associated with General Cognitive Ability in Humans.

    PubMed

    Gregory, Michael D; Kippenhan, J Shane; Dickinson, Dwight; Carrasco, Jessica; Mattay, Venkata S; Weinberger, Daniel R; Berman, Karen F

    2016-05-23

    Searching for a neurobiological understanding of human intellectual capabilities has long occupied those very capabilities. Brain gyrification, or folding of the cortex, is as highly evolved and variable a characteristic in humans as is intelligence. Indeed, gyrification scales with brain size, and relationships between brain size and intelligence have been demonstrated in humans [1-3]. However, gyrification shows a large degree of variability that is independent from brain size [4-6], suggesting that the former may independently contribute to cognitive abilities and thus supporting a direct investigation of this parameter in the context of intelligence. Moreover, uncovering the regional pattern of such an association could offer insights into evolutionary and neural mechanisms. We tested for this brain-behavior relationship in two separate, independently collected, large cohorts-440 healthy adults and 662 healthy children-using high-resolution structural neuroimaging and comprehensive neuropsychometric batteries. In both samples, general cognitive ability was significantly associated (pFDR < 0.01) with increasing gyrification in a network of neocortical regions, including large portions of the prefrontal cortex, inferior parietal lobule, and temporoparietal junction, as well as the insula, cingulate cortex, and fusiform gyrus, a regional distribution that was nearly identical in both samples (Dice similarity coefficient = 0.80). This neuroanatomical pattern is consistent with an existing, well-known proposal, the Parieto-Frontal Integration Theory of intelligence [7], and is also consistent with research in comparative evolutionary biology showing rapid neocortical expansion of these regions in humans relative to other species. These data provide a framework for understanding the neurobiology of human cognitive abilities and suggest a potential neurocellular association. PMID:27133866

  18. Regional Brain Shrinkage over Two Years: Individual Differences and Effects of Pro-Inflammatory Genetic Polymorphisms

    PubMed Central

    Persson, N.; Ghisletta, P.; Dahle, C.L.; Bender, A.R.; Yang, Y.; Yuan, P.; Daugherty, A.M.; Raz, N.

    2014-01-01

    We examined regional changes in brain volume in healthy adults (N = 167, age 19-79 years at baseline; N = 90 at follow-up) over approximately two years. With latent change score models, we evaluated mean change and individual differences in rates of change in 10 anatomically-defined and manually-traced regions of interest (ROIs): lateral prefrontal cortex (LPFC), orbital frontal cortex (OF), prefrontal white matter (PFw), hippocampus (HC), parahippocampal gyrus (PhG), caudate nucleus (Cd), putamen (Pt), insula (In), cerebellar hemispheres (CbH), and primary visual cortex (VC). Significant mean shrinkage was observed in the HC, CbH, In, OF, and the PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants mediated shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1β (IL-1βC-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFRC677T, rs1801133) polymorphisms showed increased PhG shrinkage. No effects of a pro-inflammatory polymorphism for C-reactive protein (CRP-286C>A>T, rs3091244) or apolipoprotein (APOE) ε4 allele were noted. These results replicate the pattern of brain shrinkage observed in previous studies, with a notable exception of the LPFC thus casting doubt on the unique importance of prefrontal cortex in aging. Larger baseline volumes of CbH and In were associated with increased shrinkage, in conflict with the brain reserve hypothesis. Contrary to previous reports, we observed no significant linear effects of age and hypertension on regional brain shrinkage. Our findings warrant further investigation of the effects of neuroinflammation on structural brain change throughout the lifespan. PMID:25264227

  19. Region-specific changes in presynaptic agmatine and glutamate levels in the aged rat brain.

    PubMed

    Jing, Y; Liu, P; Leitch, B

    2016-01-15

    During the normal aging process, the brain undergoes a range of biochemical and structural alterations, which may contribute to deterioration of sensory and cognitive functions. Age-related deficits are associated with altered efficacy of synaptic neurotransmission. Emerging evidence indicates that levels of agmatine, a putative neurotransmitter in the mammalian brain, are altered in a region-specific manner during the aging process. The gross tissue content of agmatine in the prefrontal cortex (PFC) of aged rat brains is decreased whereas levels in the temporal cortex (TE) are increased. However, it is not known whether these changes in gross tissue levels are also mirrored by changes in agmatine levels at synapses and thus could potentially contribute to altered synaptic function with age. In the present study, agmatine levels in presynaptic terminals in the PFC and TE regions (300 terminals/region) of young (3month; n=3) and aged (24month; n=3) brains of male Sprague-Dawley rats were compared using quantitative post-embedding immunogold electron-microscopy. Presynaptic levels of agmatine were significantly increased in the TE region (60%; p<0.001) of aged rats compared to young rats, however no significant differences were detected in synaptic levels in the PFC region. Double immunogold labeling indicated that agmatine and glutamate were co-localized in the same synaptic terminals, and quantitative analyses revealed significantly reduced glutamate levels in agmatine-immunopositive synaptic terminals in both regions in aged rats compared to young animals. This study, for the first time, demonstrates differential effects of aging on agmatine and glutamate in the presynaptic terminals of PFC and TE. Future research is required to understand the functional significance of these changes and the underlying mechanisms. PMID:26548412

  20. Changes of the directional brain networks related with brain plasticity in patients with long-term unilateral sensorineural hearing loss.

    PubMed

    Zhang, G-Y; Yang, M; Liu, B; Huang, Z-C; Li, J; Chen, J-Y; Chen, H; Zhang, P-P; Liu, L-J; Wang, J; Teng, G-J

    2016-01-28

    Previous studies often report that early auditory deprivation or congenital deafness contributes to cross-modal reorganization in the auditory-deprived cortex, and this cross-modal reorganization limits clinical benefit from cochlear prosthetics. However, there are inconsistencies among study results on cortical reorganization in those subjects with long-term unilateral sensorineural hearing loss (USNHL). It is also unclear whether there exists a similar cross-modal plasticity of the auditory cortex for acquired monaural deafness and early or congenital deafness. To address this issue, we constructed the directional brain functional networks based on entropy connectivity of resting-state functional MRI and researched changes of the networks. Thirty-four long-term USNHL individuals and seventeen normally hearing individuals participated in the test, and all USNHL patients had acquired deafness. We found that certain brain regions of the sensorimotor and visual networks presented enhanced synchronous output entropy connectivity with the left primary auditory cortex in the left long-term USNHL individuals as compared with normally hearing individuals. Especially, the left USNHL showed more significant changes of entropy connectivity than the right USNHL. No significant plastic changes were observed in the right USNHL. Our results indicate that the left primary auditory cortex (non-auditory-deprived cortex) in patients with left USNHL has been reorganized by visual and sensorimotor modalities through cross-modal plasticity. Furthermore, the cross-modal reorganization also alters the directional brain functional networks. The auditory deprivation from the left or right side generates different influences on the human brain. PMID:26621123

  1. Regional Health and Function in the hippocampus: Evolutionary compromises for a critical brain region

    PubMed Central

    Jackson, Travis C.; Foster, Thomas C.

    2009-01-01

    The hippocampus is especially vulnerable to damage caused by metabolic dysregulation. However distinct sub-regions within the hippocampus differ by their relative susceptibility to such damage. Region CA1 pyramidal neurons are most sensitive to metabolic perturbations while region CA3 pyramidal neurons show more resistance, and these unique profiles of susceptibility are but one example that differentiates CA1/CA3 neurons. We present here a hypothesis that inextricably links the unique biochemistries of learning and memory in region CA1, to that of cell survival signaling, and in so doing, suggest an explanation for region CA1 susceptibility to metabolic dysfunction. Further, we propose a signaling mechanism to explain how both pathways can be simultaneously regulated. Critical to this process is the protein phosphatase PHLPP1. Finally we discuss the implications of this hypothesis and the inherent challenges it poses for treatment of neurological disorders resulting in reduced hippocampal function by increased neuron death. PMID:20161206

  2. The Brain As a Mixer, I. Preliminary Literature Review: Auditory Integration. Studies in Language and Language Behavior, Progress Report Number VII.

    ERIC Educational Resources Information Center

    Semmel, Melvyn I.; And Others

    Methods to evaluate central hearing deficiencies and to localize brain damage are reviewed beginning with Bocca who showed that patients with temporal lobe tumors made significantly lower discrimination scores in the ear opposite the tumor when speech signals were distorted. Tests were devised to attempt to pinpoint brain damage on the basis of…

  3. Different Brain Regions are Infected with Fungi in Alzheimer’s Disease

    PubMed Central

    Pisa, Diana; Alonso, Ruth; Rábano, Alberto; Rodal, Izaskun; Carrasco, Luis

    2015-01-01

    The possibility that Alzheimer’s disease (AD) has a microbial aetiology has been proposed by several researchers. Here, we provide evidence that tissue from the central nervous system (CNS) of AD patients contain fungal cells and hyphae. Fungal material can be detected both intra- and extracellularly using specific antibodies against several fungi. Different brain regions including external frontal cortex, cerebellar hemisphere, entorhinal cortex/hippocampus and choroid plexus contain fungal material, which is absent in brain tissue from control individuals. Analysis of brain sections from ten additional AD patients reveals that all are infected with fungi. Fungal infection is also observed in blood vessels, which may explain the vascular pathology frequently detected in AD patients. Sequencing of fungal DNA extracted from frozen CNS samples identifies several fungal species. Collectively, our findings provide compelling evidence for the existence of fungal infection in the CNS from AD patients, but not in control individuals. PMID:26468932

  4. Regional brain volumes changes in adult male FMR1-KO mouse on the FVB strain.

    PubMed

    Lai, J K Y; Lerch, J P; Doering, L C; Foster, J A; Ellegood, J

    2016-03-24

    Fragile X Syndrome (FXS) is the most common heritable single gene cause of autism spectrum disorder (ASD). FMR1-KO mice mimic the etiology and phenotypic manifestations of FXS. Neuroanatomical changes in specific brain regions have been reported in clinical settings and in preclinical models. FMR1-KO mice have been generated in different strains including C57Bl/6 (B6) and FVB. Mice on different genetic backgrounds have stable yet distinct behavioral phenotypes that may lead to unique gene-strain interactions on brain structure. Previous magnetic resonance imaging (MRI) studies have examined FMR1 knockout male mice on a B6 and found few differences compared to wild-type mice. Here, we examine brain volumes in FMR1 knockout male mice on a FVB background using high resolution (multi-channel 7.0Tesla) MRI. We observe multiple differences in the neuroanatomy of male FMR1-/y mice on a FVB background. Significantly larger relative volume (% total brain volume) differences were found in major white matter structures throughout the brain. In addition, there were changes in areas associated with fronto-striatal circuitry and other regions. Functional and structural connectivity differences are often seen in human ASD, and therefore, this increased white matter seen in the FMR1-KO-FVB could be highlighting a structural over-connectivity, which could lead to some of the behavioral abnormalities seen with the FMR1-KO-FVB mice. Furthermore, these results highlight the importance of genetic strain contribution to brain structure. PMID:26794591

  5. Age- and brain-region-specific effects of dietary vitamin K on myelin sulfatides

    PubMed Central

    Crivello, Natalia A.; Casseus, Sherley L.; Peterson, James W.; Smith, Donald E.; Booth, Sarah L.

    2009-01-01

    Dysregulation of myelin sulfatides is a risk factor for cognitive decline with age. Vitamin K is present in high concentrations in the brain and has been implicated in the regulation of sulfatide metabolism. Our objective was to investigate the age-related interrelation between dietary vitamin K and sulfatides in myelin fractions isolated from the brain regions of Fischer 344 male rats fed one of two dietary forms of vitamin K: phylloquinone or its hydrogenated form, dihydrophylloquinone for 28 days. Both dietary forms of vitamin K were converted to menaquinone-4 in the brain. The efficiency of dietary dihydrophylloquinone conversion to menaquinone-4 compared to dietary phylloquinone was lower in the striatum and cortex, and was similar to those in the hippocampus. There were significant positive correlations between sulfatides and menaquinone-4 in the hippocampus (phylloquinone-supplemented diet -12mo and 24mo; dihydrophylloquinone -supplemented diet - 12mo) and cortex (phylloquinone-supplemented diet -12mo and 24 mo). No significant correlations were observed in the striatum. Furthermore, sulfatides in the hippocampus were significantly positively correlated with MK-4 in serum. This is the first attempt to establish and characterize a novel animal model that exploits the inability of dietary dihydrophylloquinone to convert to brain menaquinone-4 to study the dietary effects of vitamin K on brain sulfatide in brain regions controlling motor and cognitive functions. Our findings suggest that this animal model may be useful for investigation of the effect of the dietary vitamin K on sulfatide metabolism, myelin structure, and behavior functions. PMID:20092997

  6. Conceptual priming for realistic auditory scenes and for auditory words.

    PubMed

    Frey, Aline; Aramaki, Mitsuko; Besson, Mireille

    2014-02-01

    Two experiments were conducted using both behavioral and Event-Related brain Potentials methods to examine conceptual priming effects for realistic auditory scenes and for auditory words. Prime and target sounds were presented in four stimulus combinations: Sound-Sound, Word-Sound, Sound-Word and Word-Word. Within each combination, targets were conceptually related to the prime, unrelated or ambiguous. In Experiment 1, participants were asked to judge whether the primes and targets fit together (explicit task) and in Experiment 2 they had to decide whether the target was typical or ambiguous (implicit task). In both experiments and in the four stimulus combinations, reaction times and/or error rates were longer/higher and the N400 component was larger to ambiguous targets than to conceptually related targets, thereby pointing to a common conceptual system for processing auditory scenes and linguistic stimuli in both explicit and implicit tasks. However, fine-grained analyses also revealed some differences between experiments and conditions in scalp topography and duration of the priming effects possibly reflecting differences in the integration of perceptual and cognitive attributes of linguistic and nonlinguistic sounds. These results have clear implications for the building-up of virtual environments that need to convey meaning without words. PMID:24378910

  7. Localizing the human primary auditory cortex in vivo using structural MRI.

    PubMed

    Wasserthal, Christian; Brechmann, André; Stadler, Jörg; Fischl, Bruce; Engel, Karin

    2014-06-01

    Currently there are no routine methods to delineate the primary auditory cortex (PAC) of humans in vivo. Due to the large differences in the location of the PAC between subjects, labels derived from post-mortem brains may be inaccurate when applied to different samples of in vivo brains. Recent magnetic resonance (MR) imaging studies suggested that MR-tissue properties can be used to define the location of the PAC region in vivo. The basis for such an approach is that the PAC region is more strongly myelinated than the secondary areas. We developed a fully automatic method to identify the PAC in conventional anatomical data using a combination of two complementary MR contrasts, i.e., T1 and T2, at 3T with 0.7mm isotropic resolution. Our algorithm maps the anatomical MR data to reconstructed cortical surfaces and uses a classification approach to create an artificial contrast that is highly sensitive to the effects of an increased myelination of the cortex. Consistent with the location of the PAC defined in post-mortem brains, we found a compact region on the medial two thirds of Heschl's gyrus in both hemispheres of all 39 subjects. With further improvements in signal-to-noise ratio of the anatomical data and manual correction of segmentation errors, the results suggest that the primary auditory cortex can be defined in the living brain of single subjects. PMID:23891882

  8. Aging and auditory site of lesion.

    PubMed

    Otto, W C; McCandless, G A

    1982-01-01

    The purpose of this study was to examine and quantify the functional auditory problems of presbycusis through a battery of recently developed diagnostic tests and to evaluate the usefulness of these tests with an elderly population. Diagnostic measures used were impedence measures, speech discrimination tests, synthetic sentence identification, compressed speech, two measures of tone decay, the short increment sensitivity index, a digit span test, and auditory brain stem response audiometry. Significant differences were found between scores for elderly subjects and those of young subjects who had similar audiograms. Use of the Metz test as an objective measure of recruitment yielded results suggesting a higher incidence of recruitment than evidenced by previous studies using loudness balancing procedures. The Olsen-Noffsinger procedure of quantifying tone decay revealed a greater difference between age groups than did the Suprathreshold Adaptation Test. Synthetic sentence identification revealed the most consistent age effect among the tests of central auditory function. Auditory brain stem response audiometry revealed several examples of abnormally long interpeak latencies. It is concluded that there is both behavioral and electrophysiological evidence of central and peripheral auditory disorder frequently accompanying senescence. PMID:7095318

  9. Functional MRI Preprocessing in Lesioned Brains: Manual Versus Automated Region of Interest Analysis

    PubMed Central

    Garrison, Kathleen A.; Rogalsky, Corianne; Sheng, Tong; Liu, Brent; Damasio, Hanna; Winstein, Carolee J.; Aziz-Zadeh, Lisa S.

    2015-01-01

    Functional magnetic resonance imaging (fMRI) has significant potential in the study and treatment of neurological disorders and stroke. Region of interest (ROI) ana