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Sample records for functional neuroimaging analyses

  1. Functional neuroimaging in psychiatry.

    PubMed Central

    Fu, C H; McGuire, P K

    1999-01-01

    Functional neuroimaging is one of the most powerful means available for investigating the pathophysiology of psychiatric disorders. In this review, we shall focus on the different ways that it can be employed to this end, describing the major findings in the field in the context of different methodological approaches. We will also discuss practical issues that are particular to studying psychiatric disorders and the potential contribution of functional neuroimaging to future psychiatric research. PMID:10466156

  2. Reproducibility of neuroimaging analyses across operating systems.

    PubMed

    Glatard, Tristan; Lewis, Lindsay B; Ferreira da Silva, Rafael; Adalat, Reza; Beck, Natacha; Lepage, Claude; Rioux, Pierre; Rousseau, Marc-Etienne; Sherif, Tarek; Deelman, Ewa; Khalili-Mahani, Najmeh; Evans, Alan C

    2015-01-01

    Neuroimaging pipelines are known to generate different results depending on the computing platform where they are compiled and executed. We quantify these differences for brain tissue classification, fMRI analysis, and cortical thickness (CT) extraction, using three of the main neuroimaging packages (FSL, Freesurfer and CIVET) and different versions of GNU/Linux. We also identify some causes of these differences using library and system call interception. We find that these packages use mathematical functions based on single-precision floating-point arithmetic whose implementations in operating systems continue to evolve. While these differences have little or no impact on simple analysis pipelines such as brain extraction and cortical tissue classification, their accumulation creates important differences in longer pipelines such as subcortical tissue classification, fMRI analysis, and cortical thickness extraction. With FSL, most Dice coefficients between subcortical classifications obtained on different operating systems remain above 0.9, but values as low as 0.59 are observed. Independent component analyses (ICA) of fMRI data differ between operating systems in one third of the tested subjects, due to differences in motion correction. With Freesurfer and CIVET, in some brain regions we find an effect of build or operating system on cortical thickness. A first step to correct these reproducibility issues would be to use more precise representations of floating-point numbers in the critical sections of the pipelines. The numerical stability of pipelines should also be reviewed.

  3. Developments in functional neuroimaging techniques

    SciTech Connect

    Aine, C.J.

    1995-03-01

    A recent review of neuroimaging techniques indicates that new developments have primarily occurred in the area of data acquisition hardware/software technology. For example, new pulse sequences on standard clinical imagers and high-powered, rapidly oscillating magnetic field gradients used in echo planar imaging (EPI) have advanced MRI into the functional imaging arena. Significant developments in tomograph design have also been achieved for monitoring the distribution of positron-emitting radioactive tracers in the body (PET). Detector sizes, which pose a limit on spatial resolution, have become smaller (e.g., 3--5 mm wide) and a new emphasis on volumetric imaging has emerged which affords greater sensitivity for determining locations of positron annihilations and permits smaller doses to be utilized. Electromagnetic techniques have also witnessed growth in the ability to acquire data from the whole head simultaneously. EEG techniques have increased their electrode coverage (e.g., 128 channels rather than 16 or 32) and new whole-head systems are now in use for MEG. But the real challenge now is in the design and implementation of more sophisticated analyses to effectively handle the tremendous amount of physiological/anatomical data that can be acquired. Furthermore, such analyses will be necessary for integrating data across techniques in order to provide a truly comprehensive understanding of the functional organization of the human brain.

  4. Functional Neuroimaging: A Physiological Perspective

    PubMed Central

    Lin, Ai-Ling; Gao, Jia-Hong; Duong, Timonthy Q.; Fox, Peter T.

    2010-01-01

    Metabolic physiology and functional neuroimaging have played important and complementary roles over the past two decades. In particular, investigations of the mechanisms underlying functional neuroimaging signals have produced fundamental new insights into hemodynamic and metabolic regulation. However, controversies were also raised as regards the metabolic pathways (oxidative vs. non-oxidative) for meeting the energy demand and driving the increases in cerebral blood flow (CBF) during brain activation. In a recent study, with the concurrent functional MRI-MRS measurements, we found that task-evoked energy demand was predominately met through oxidative metabolism (approximately 98%), despite a small increase in cerebral metabolic rate of oxygen (12–17%). In addition, the task-induced increases in CBF were most likely mediated by anaerobic glycolysis rather than oxygen demand. These observations and others from functional neuroimaging support the activation-induced neuron-astrocyte interactions portrayed by the astrocyte-neuron lactate shuttle model. The concurrent developments of neuroimaging methods and metabolic physiology will also pave the way for the future investigation of cerebral hemodynamics and metabolism in disease states. PMID:20725632

  5. Functional near-infrared neuroimaging.

    PubMed

    Izzetoglu, Kurtulus; Bunce, Scott; Izzetoglu, Meltem; Onaral, Banu; Pourrezaei, Kambiz

    2004-01-01

    Functional near-infrared (fNIR) spectroscopy is a wearable neuroimaging device that enables the continuous, non-invasive, and portable monitoring of changes in blood oxygen and blood volume related to human brain function. Over the last three years, studies in the laboratory and under field conditions have established the positive correlation between a participant's performance and oxygenation responses as a function of task load. Our findings indicate that fNIR can effectively monitor attention and working memory in real-life situations. These experimental outcomes compare favorably with functional magnetic resonance imaging (fMRI) studies, and in particular, with the blood oxygenation level dependent (BOLD) signal. The capacity to monitor brain hemodynamics with a wearable device holds promise for the use of fNIR in the creation of a symbiotic relationship between the user and his/her everyday environment. Moreover, under operational conditions, the fNIR system is amenable to integration with other established physiological and neurobehavioral measures, including EEG, eye tracking, pupil reflex, heart rate variability, respiration and electrodermal activity.

  6. On study design in neuroimaging heritability analyses

    NASA Astrophysics Data System (ADS)

    Koran, Mary Ellen; Li, Bo; Jahanshad, Neda; Thornton-Wells, Tricia A.; Glahn, David C.; Thompson, Paul M.; Blangero, John; Nichols, Thomas E.; Kochunov, Peter; Landman, Bennett A.

    2014-03-01

    Imaging genetics is an emerging methodology that combines genetic information with imaging-derived metrics to understand how genetic factors impact observable structural, functional, and quantitative phenotypes. Many of the most well-known genetic studies are based on Genome-Wide Association Studies (GWAS), which use large populations of related or unrelated individuals to associate traits and disorders with individual genetic factors. Merging imaging and genetics may potentially lead to improved power of association in GWAS because imaging traits may be more sensitive phenotypes, being closer to underlying genetic mechanisms, and their quantitative nature inherently increases power. We are developing SOLAR-ECLIPSE (SE) imaging genetics software which is capable of performing genetic analyses with both large-scale quantitative trait data and family structures of variable complexity. This program can estimate the contribution of genetic commonality among related subjects to a given phenotype, and essentially answer the question of whether or not the phenotype is heritable. This central factor of interest, heritability, offers bounds on the direct genetic influence over observed phenotypes. In order for a trait to be a good phenotype for GWAS, it must be heritable: at least some proportion of its variance must be due to genetic influences. A variety of family structures are commonly used for estimating heritability, yet the variability and biases for each as a function of the sample size are unknown. Herein, we investigate the ability of SOLAR to accurately estimate heritability models based on imaging data simulated using Monte Carlo methods implemented in R. We characterize the bias and the variability of heritability estimates from SOLAR as a function of sample size and pedigree structure (including twins, nuclear families, and nuclear families with grandparents).

  7. Functional neuroimaging: technical, logical, and social perspectives.

    PubMed

    Aguirre, Geoffrey K

    2014-01-01

    Neuroscientists have long sought to study the dynamic activity of the human brain-what's happening in the brain, that is, while people are thinking, feeling, and acting. Ideally, an inside look at brain function would simultaneously and continuously measure the biochemical state of every cell in the central nervous system. While such a miraculous method is science fiction, a century of progress in neuroimaging technologies has made such simultaneous and continuous measurement a plausible fiction. Despite this progress, practitioners of modern neuroimaging struggle with two kinds of limitations: those that attend the particular neuroimaging methods we have today and those that would limit any method of imaging neural activity, no matter how powerful. In this essay, I consider the liabilities and potential of techniques that measure human brain activity. I am concerned here only with methods that measure relevant physiologic states of the central nervous system and relate those measures to particular mental states. I will consider in particular the preeminent method of functional neuroimaging: BOLD fMRI. While there are several practical limits on the biological information that current technologies can measure, these limits-as important as they are-are minor in comparison to the fundamental logical restraints on the conclusions that can be drawn from brain imaging studies.

  8. Functional neuroimaging of extraversion-introversion.

    PubMed

    Lei, Xu; Yang, Tianliang; Wu, Taoyu

    2015-12-01

    Neuroimaging techniques such as functional magnetic resonance imaging and positron emission tomography have provided an unprecedented neurobiological perspective for research on personality traits. Evidence from task-related neuroimaging has shown that extraversion is associated with activations in regions of the anterior cingulate cortex, dorsolateral prefrontal cortex, middle temporal gyrus and the amygdala. Currently, resting-state neuroimaging is being widely used in cognitive neuroscience. Initial exploration of extraversion has revealed correlations with the medial prefrontal cortex, anterior cingulate cortex, insular cortex, and the precuneus. Recent research work has indicated that the long-range temporal dependence of the resting-state spontaneous oscillation has high test-retest reliability. Moreover, the long-range temporal dependence of the resting-state networks is highly correlated with personality traits, and this can be used for the prediction of extraversion. As the long-range temporal dependence reflects real-time information updating in individuals, this method may provide a new approach to research on personality traits.

  9. Applications of Epsilon Radial Networks in Neuroimage Analyses

    PubMed Central

    Adluru, Nagesh; Chung, Moo K.; Lange, Nicholas T.; Lainhart, Janet E.; Alexander, Andrew L.

    2016-01-01

    “Is the brain ’wiring’ different between groups of populations?” is an increasingly important question with advances in diffusion MRI and abundance of network analytic tools. Recently, automatic, data-driven and computationally efficient framework for extracting brain networks using tractography and epsilon neighborhoods were proposed in the diffusion tensor imaging (DTI) literature [1]. In this paper we propose new extensions to that framework and show potential applications of such epsilon radial networks (ERN) in performing various types of neuroimage analyses. These extensions allow us to use ERNs not only to mine for topo-physical properties of the structural brain networks but also to perform classical region-of-interest (ROI) analyses in a very efficient way. Thus we demonstrate the use of ERNs as a novel image processing lens for statistical and machine learning based analyses. We demonstrate its application in an autism study for identifying topological and quantitative group differences, as well as performing classification. Finally, these views are not restricted to ERNs but can be effective for population studies using any computationally efficient network-extraction procedures. PMID:28251191

  10. [Functional neuroimaging of auditory hallucinations in schizophrenia].

    PubMed

    Font, M; Parellada, E; Fernández-Egea, E; Bernardo, M; Lomeña, F

    2003-01-01

    The neurobiological bases underlying the generation of auditory hallucinations, a distressing and paradigmatic symptom of schizophrenia, are still unknown in spite of in-depth phenomenological descriptions. This work aims to make a critical review of the latest published literature in recent years, focusing on functional neuroimaging studies (PET, SPECT, fMRI) of auditory hallucinations. Thus, the studies are classified according to whether they are sensory activation, trait and state. The two main hypotheses proposed to explain the phenomenon, external speech vs. subvocal or inner speech, are also explained. Finally, the latest unitary theory as well as the limitations the studies published are commented on. The need to continue investigating in this field, that is still underdeveloped, is posed in order to understand better the etiopathogenesis of auditory hallucinations in schizophrenia.

  11. Turner Syndrome: Neuroimaging Findings--Structural and Functional

    ERIC Educational Resources Information Center

    Mullaney, Ronan; Murphy, Declan

    2009-01-01

    Neuroimaging studies of Turner syndrome can advance our understanding of the X chromosome in brain development, and the modulatory influence of endocrine factors. There is increasing evidence from neuroimaging studies that TX individuals have significant differences in the anatomy, function, and metabolism of a number of brain regions; including…

  12. Multimodal functional neuroimaging: integrating functional MRI and EEG/MEG.

    PubMed

    He, Bin; Liu, Zhongming

    2008-01-01

    Noninvasive functional neuroimaging, as an important tool for basic neuroscience research and clinical diagnosis, continues to face the need of improving the spatial and temporal resolution. While existing neuroimaging modalities might approach their limits in imaging capability mostly due to fundamental as well as technical reasons, it becomes increasingly attractive to integrate multiple complementary modalities in an attempt to significantly enhance the spatiotemporal resolution that cannot be achieved by any modality individually. Electrophysiological and hemodynamic/metabolic signals reflect distinct but closely coupled aspects of the underlying neural activity. Combining fMRI and EEG/MEG data allows us to study brain function from different perspectives. In this review, we start with an overview of the physiological origins of EEG/MEG and fMRI, as well as their fundamental biophysics and imaging principles, we proceed with a review of the major advances in the understanding and modeling of neurovascular coupling and in the methodologies for the fMRI-EEG/MEG simultaneous recording. Finally, we summarize important remaining issues and perspectives concerning multimodal functional neuroimaging, including brain connectivity imaging.

  13. Functional neuroimaging of traumatic brain injury: advances and clinical utility

    PubMed Central

    Irimia, Andrei; Van Horn, John Darrell

    2015-01-01

    Functional deficits due to traumatic brain injury (TBI) can have significant and enduring consequences upon patients’ life quality and expectancy. Although functional neuroimaging is essential for understanding TBI pathophysiology, an insufficient amount of effort has been dedicated to the task of translating functional neuroimaging findings into information with clinical utility. The purpose of this review is to summarize the use of functional neuroimaging techniques – especially functional magnetic resonance imaging, diffusion tensor imaging, positron emission tomography, magnetic resonance spectroscopy, and electroencephalography – for advancing current knowledge of TBI-related brain dysfunction and for improving the rehabilitation of TBI patients. We focus on seven core areas of functional deficits, namely consciousness, motor function, attention, memory, higher cognition, personality, and affect, and, for each of these, we summarize recent findings from neuroimaging studies which have provided substantial insight into brain function changes due to TBI. Recommendations are also provided to aid in setting the direction of future neuroimaging research and for understanding brain function changes after TBI. PMID:26396520

  14. Multimodal Functional Neuroimaging: Integrating Functional MRI and EEG/MEG

    PubMed Central

    He, Bin; Liu, Zhongming

    2010-01-01

    Noninvasive functional neuroimaging, as an important tool for basic neuroscience research and clinical diagnosis, continues to face the need of improving the spatial and temporal resolution. While existing neuroimaging modalities might approach their limits in imaging capability mostly due to fundamental as well as technical reasons, it becomes increasingly attractive to integrate multiple complementary modalities in an attempt to significantly enhance the spatiotemporal resolution that cannot be achieved by any modality individually. Electrophysiological and hemodynamic/metabolic signals reflect distinct but closely coupled aspects of the underlying neural activity. Combining fMRI and EEG/MEG data allows us to study brain function from different perspectives. In this review, we start with an overview of the physiological origins of EEG/MEG and fMRI, as well as their fundamental biophysics and imaging principles; it is followed by a review of major progresses in understanding and modeling the neurovascular coupling, methodologies for the fMRI-EEG/MEG integration and EEG-fMRI simultaneous recording; finally, important remaining issues and perspectives (including brain connectivity imaging) are summarized. PMID:20634915

  15. Functional neuroimaging studies of the effects of psychotherapy.

    PubMed

    Beauregard, Mario

    2014-03-01

    It has been long established that psychological interventions can markedly alter patients' thinking patterns, beliefs, attitudes, emotional states, and behaviors. Little was known about the neural mechanisms mediating such alterations before the advent of functional neuroimaging techniques. Since the turn of the new millenium, several functional neuroimaging studies have been conducted to tackle this important issue. Some of these studies have explored the neural impact of various forms of psychotherapy in individuals with major depressive disorder. Other neuroimaging studies have investigated the effects of psychological interventions for anxiety disorders. I review these studies in the present article, and discuss the putative neural mechanisms of change in psychotherapy. The findings of these studies suggest that mental and behavioral changes occurring during psychotherapeutic interventions can lead to a normalization of functional brain activity at a global level.

  16. Uncovering the etiology of conversion disorder: insights from functional neuroimaging

    PubMed Central

    Ejareh dar, Maryam; Kanaan, Richard AA

    2016-01-01

    Conversion disorder (CD) is a syndrome of neurological symptoms arising without organic cause, arguably in response to emotional stress, but the exact neural substrates of these symptoms and the underlying mechanisms remain poorly understood with the hunt for a biological basis afoot for centuries. In the past 15 years, novel insights have been gained with the advent of functional neuroimaging studies in patients suffering from CDs in both motor and nonmotor domains. This review summarizes recent functional neuroimaging studies including functional magnetic resonance imaging (fMRI), single photon emission computerized tomography (SPECT), and positron emission tomography (PET) to see whether they bring us closer to understanding the etiology of CD. Convergent functional neuroimaging findings suggest alterations in brain circuits that could point to different mechanisms for manifesting functional neurological symptoms, in contrast with feigning or healthy controls. Abnormalities in emotion processing and in emotion-motor processing suggest a diathesis, while differential reactions to certain stressors implicate a specific response to trauma. No comprehensive theory emerges from these clues, and all results remain preliminary, but functional neuroimaging has at least given grounds for hope that a model for CD may soon be found. PMID:26834476

  17. Uncovering the etiology of conversion disorder: insights from functional neuroimaging.

    PubMed

    Ejareh Dar, Maryam; Kanaan, Richard Aa

    2016-01-01

    Conversion disorder (CD) is a syndrome of neurological symptoms arising without organic cause, arguably in response to emotional stress, but the exact neural substrates of these symptoms and the underlying mechanisms remain poorly understood with the hunt for a biological basis afoot for centuries. In the past 15 years, novel insights have been gained with the advent of functional neuroimaging studies in patients suffering from CDs in both motor and nonmotor domains. This review summarizes recent functional neuroimaging studies including functional magnetic resonance imaging (fMRI), single photon emission computerized tomography (SPECT), and positron emission tomography (PET) to see whether they bring us closer to understanding the etiology of CD. Convergent functional neuroimaging findings suggest alterations in brain circuits that could point to different mechanisms for manifesting functional neurological symptoms, in contrast with feigning or healthy controls. Abnormalities in emotion processing and in emotion-motor processing suggest a diathesis, while differential reactions to certain stressors implicate a specific response to trauma. No comprehensive theory emerges from these clues, and all results remain preliminary, but functional neuroimaging has at least given grounds for hope that a model for CD may soon be found.

  18. Memory Systems, Processing Modes, and Components: Functional Neuroimaging Evidence.

    PubMed

    Cabeza, Roberto; Moscovitch, Morris

    2013-01-01

    In the 1980s and 1990s, there was a major theoretical debate in the memory domain regarding the multiple memory systems and processing modes frameworks. The components of processing framework argued for a middle ground: Instead of neatly divided memory systems or processing modes, this framework proposed the existence of numerous processing components that are recruited in different combinations by memory tasks and yield complex patterns of associations and dissociations. Because behavioral evidence was not sufficient to decide among these three frameworks, the debate was largely abandoned. However, functional neuroimaging evidence accumulated during the last two decades resolves the stalemate, because this evidence is more consistent with the components framework than with the other two frameworks. For example, functional neuroimaging evidence shows that brain regions attributed to one memory system can contribute to tasks associated with other memory systems and that brain regions attributed to the same processing mode (perceptual or conceptual) can be dissociated from each other. Functional neuroimaging evidence suggests that memory processes are supported by transient interactions between a few regions called process-specific alliances. These conceptual developments are an example of how functional neuroimaging can contribute to theoretical debates in cognitive psychology.

  19. Pain perception and hypnosis: findings from recent functional neuroimaging studies.

    PubMed

    Del Casale, Antonio; Ferracuti, Stefano; Rapinesi, Chiara; Serata, Daniele; Caltagirone, Saverio Simone; Savoja, Valeria; Piacentino, Daria; Callovini, Gemma; Manfredi, Giovanni; Sani, Gabriele; Kotzalidis, Georgios D; Girardi, Paolo

    2015-01-01

    Hypnosis modulates pain perception and tolerance by affecting cortical and subcortical activity in brain regions involved in these processes. By reviewing functional neuroimaging studies focusing on pain perception under hypnosis, the authors aimed to identify brain activation-deactivation patterns occurring in hypnosis-modulated pain conditions. Different changes in brain functionality occurred throughout all components of the pain network and other brain areas. The anterior cingulate cortex appears to be central in modulating pain circuitry activity under hypnosis. Most studies also showed that the neural functions of the prefrontal, insular, and somatosensory cortices are consistently modified during hypnosis-modulated pain conditions. Functional neuroimaging studies support the clinical use of hypnosis in the management of pain conditions.

  20. Functional neuroimaging of dressing-related skills

    PubMed Central

    Lovelace, Christopher T.; Foster, Donald J.; Maldjian, Joseph A.

    2015-01-01

    Restoration of motor function following stroke involves reorganization of motor output through intact pathways, with compensatory brain activity likely variable by task. One class of motor tasks, those involved in self-care, is particularly important in stroke rehabilitation. Identifying the brain areas that are engaged in self-care and how they reorganize after stroke may enable development of more effective rehabilitation strategies. We piloted a paradigm for functional MRI assessment of self-care activity. In two groups, young adults and older adults, two self-care tasks (buttoning and zipping) produce activation similar to a bimanual tapping task, with bilateral activation of primary and secondary motor cortices, primary sensory cortex, and cerebellum. Quantitative differences include more activation of sensorimotor cortex and cerebellum in buttoning than bimanual tapping. Pilot subjects with stroke showed greater superior parietal activity across tasks than controls, potentially representing an increased need for sensorimotor integration to perform motor tasks. PMID:23070748

  1. Functional Neuroimaging: Fundamental Principles and Clinical Applications.

    PubMed

    Khanna, Nishanth; Altmeyer, Wilson; Zhuo, Jiachen; Steven, Andrew

    2015-04-01

    Functional imaging modalities, such as functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), are rapidly changing the scope and practice of neuroradiology. While these modalities have long been used in research, they are increasingly being used in clinical practice to enable reliable identification of eloquent cortex and white matter tracts in order to guide treatment planning and to serve as a diagnostic supplement when traditional imaging fails. An understanding of the scientific principles underlying fMRI and DTI is necessary in current radiological practice. fMRI relies on a compensatory hemodynamic response seen in cortical activation and the intrinsic discrepant magnetic properties of deoxy- and oxyhemoglobin. Neuronal activity can be indirectly visualized based on a hemodynamic response, termed neurovascular coupling. fMRI demonstrates utility in identifying areas of cortical activation (i.e., task-based activation) and in discerning areas of neuronal connectivity when used during the resting state, termed resting state fMRI. While fMRI is limited to visualization of gray matter, DTI permits visualization of white matter tracts through diffusion restriction along different axes. We will discuss the physical, statistical and physiological principles underlying these functional imaging modalities and explore new promising clinical applications.

  2. Functions of the human frontoparietal attention network: Evidence from neuroimaging

    PubMed Central

    Scolari, Miranda; Seidl-Rathkopf, Katharina N; Kastner, Sabine

    2016-01-01

    Human frontoparietal cortex has long been implicated as a source of attentional control. However, the mechanistic underpinnings of these control functions have remained elusive due to limitations of neuroimaging techniques that rely on anatomical landmarks to localize patterns of activation. The recent advent of topographic mapping via functional magnetic resonance imaging (fMRI) has allowed the reliable parcellation of the network into 18 independent subregions in individual subjects, thereby offering unprecedented opportunities to address a wide range of empirical questions as to how mechanisms of control operate. Here, we review the human neuroimaging literature that has begun to explore space-based, feature-based, object-based and category-based attentional control within the context of topographically defined frontoparietal cortex. PMID:27398396

  3. Functions of the human frontoparietal attention network: Evidence from neuroimaging.

    PubMed

    Scolari, Miranda; Seidl-Rathkopf, Katharina N; Kastner, Sabine

    2015-02-01

    Human frontoparietal cortex has long been implicated as a source of attentional control. However, the mechanistic underpinnings of these control functions have remained elusive due to limitations of neuroimaging techniques that rely on anatomical landmarks to localize patterns of activation. The recent advent of topographic mapping via functional magnetic resonance imaging (fMRI) has allowed the reliable parcellation of the network into 18 independent subregions in individual subjects, thereby offering unprecedented opportunities to address a wide range of empirical questions as to how mechanisms of control operate. Here, we review the human neuroimaging literature that has begun to explore space-based, feature-based, object-based and category-based attentional control within the context of topographically defined frontoparietal cortex.

  4. Triangulating perspectives on functional neuroimaging for disorders of mental health

    PubMed Central

    2013-01-01

    Background Functional neuroimaging is being used in clinical psychiatry today despite the vigorous objections of many in the research community over issues of readiness. To date, a systematic examination of the perspectives of key stakeholders involved in this debate has not yet been attempted. To this fill this gap, we interviewed investigators who conduct functional neuroimaging studies involving adults with mood disorders, schizophrenia, obsessive compulsive disorder, and/or attention deficit hyperactivity disorder, providers who offer clinical neuroimaging services in the open marketplace, and consumers of these services, in order to understand perspectives underlying different views and practices. Methods Semi-structured interviews were conducted over the telephone. Verbal consent was obtained and all interviews were audio recorded. Interviews of investigators and service providers followed the same interview guide. A separate set of questions was developed for consumers. All interviews were transcribed and made software ready. We applied the qualitative methodology of constant comparison to analyze the data, whereby two researchers independently analyzed the results into textual themes. Coding discrepancies were discussed until consensus was achieved. Results Investigators, service providers, and consumers held many common perspectives about the potential or actual risks and benefits of functional neuroimaging for mental illness. However, we also found striking divergences. Service providers focused on the challenges posed by the persistence of symptoms based diagnostic categories, whereas the limitations of the science in this area was the challenge noted most frequently by investigators. The majority of consumers stated that their expectations were met. Conclusion Our findings point toward a fundamental tension between academic investigators on the one hand, and commercial service providers and their customers on the other. This scenario poses dangers to

  5. Functional neuroimaging of conversion disorder: The role of ancillary activation

    PubMed Central

    Burke, Matthew J.; Ghaffar, Omar; Staines, W. Richard; Downar, Jonathan; Feinstein, Anthony

    2014-01-01

    Background Previous functional neuroimaging studies investigating the neuroanatomy of conversion disorder have yielded inconsistent results that may be attributed to small sample sizes and disparate methodologies. The objective of this study was to better define the functional neuroanatomical correlates of conversion disorder. Methods Ten subjects meeting clinical criteria for unilateral sensory conversion disorder underwent fMRI during which a vibrotactile stimulus was applied to anesthetic and sensate areas. A block design was used with 4 s of stimulation followed by 26 s of rest, the pattern repeated 10 times. Event-related group averages of the BOLD response were compared between conditions. Results All subjects were right-handed females, with a mean age of 41. Group analyses revealed 10 areas that had significantly greater activation (p < .05) when stimulation was applied to the anesthetic body part compared to the contralateral sensate mirror region. They included right paralimbic cortices (anterior cingulate cortex and insula), right temporoparietal junction (angular gyrus and inferior parietal lobule), bilateral dorsolateral prefrontal cortex (middle frontal gyri), right orbital frontal cortex (superior frontal gyrus), right caudate, right ventral-anterior thalamus and left angular gyrus. There was a trend for activation of the somatosensory cortex contralateral to the anesthetic region to be decreased relative to the sensate side. Conclusions Sensory conversion symptoms are associated with a pattern of abnormal cerebral activation comprising neural networks implicated in emotional processing and sensory integration. Further study of the roles and potential interplay of these networks may provide a basis for an underlying psychobiological mechanism of conversion disorder. PMID:25379447

  6. Neuroimaging and sexual behavior: identification of regional and functional differences.

    PubMed

    Cheng, Joseph C; Secondary, Joseph; Burke, William H; Fedoroff, J Paul; Dwyer, R Gregg

    2015-07-01

    The neuroanatomical correlates of human sexual desire, arousal, and behavior have been characterized in recent years with functional brain imaging techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET). Here, we briefly review the results of functional neuroimaging studies in humans, whether healthy or suffering from sexual disorders, and the current models of regional and network activation in sexual arousal. Attention is paid, in particular, to findings from both regional and network studies in the past 3 years. We also identify yet unanswered and pressing questions of interest to areas of ongoing investigations for psychiatric, scientific, and forensic disciplines.

  7. Neuroimaging Study Designs, Computational Analyses and Data Provenance Using the LONI Pipeline

    PubMed Central

    Dinov, Ivo; Lozev, Kamen; Petrosyan, Petros; Liu, Zhizhong; Eggert, Paul; Pierce, Jonathan; Zamanyan, Alen; Chakrapani, Shruthi; Van Horn, John; Parker, D. Stott; Magsipoc, Rico; Leung, Kelvin; Gutman, Boris; Woods, Roger; Toga, Arthur

    2010-01-01

    Modern computational neuroscience employs diverse software tools and multidisciplinary expertise to analyze heterogeneous brain data. The classical problems of gathering meaningful data, fitting specific models, and discovering appropriate analysis and visualization tools give way to a new class of computational challenges—management of large and incongruous data, integration and interoperability of computational resources, and data provenance. We designed, implemented and validated a new paradigm for addressing these challenges in the neuroimaging field. Our solution is based on the LONI Pipeline environment [3], [4], a graphical workflow environment for constructing and executing complex data processing protocols. We developed study-design, database and visual language programming functionalities within the LONI Pipeline that enable the construction of complete, elaborate and robust graphical workflows for analyzing neuroimaging and other data. These workflows facilitate open sharing and communication of data and metadata, concrete processing protocols, result validation, and study replication among different investigators and research groups. The LONI Pipeline features include distributed grid-enabled infrastructure, virtualized execution environment, efficient integration, data provenance, validation and distribution of new computational tools, automated data format conversion, and an intuitive graphical user interface. We demonstrate the new LONI Pipeline features using large scale neuroimaging studies based on data from the International Consortium for Brain Mapping [5] and the Alzheimer's Disease Neuroimaging Initiative [6]. User guides, forums, instructions and downloads of the LONI Pipeline environment are available at http://pipeline.loni.ucla.edu. PMID:20927408

  8. Substrates of neuropsychological functioning in stimulant dependence: a review of functional neuroimaging research

    PubMed Central

    Crunelle, Cleo L; Veltman, Dick J; Booij, Jan; Emmerik – van Oortmerssen, Katelijne; den Brink, Wim

    2012-01-01

    Stimulant dependence is associated with neuropsychological impairments. Here, we summarize and integrate the existing neuroimaging literature on the neural substrates of neuropsychological (dys)function in stimulant dependence, including cocaine, (meth-)amphetamine, ecstasy and nicotine dependence, and excessive caffeine use, comparing stimulant abusers (SAs) to nondrug using healthy controls (HCs). Despite some inconsistencies, most studies indicated altered brain activation in prefrontal cortex (PFC) and insula in response to reward and punishment, and higher limbic and anterior cingulate cortex (ACC)/PFC activation during craving and attentional bias paradigms in SAs compared with HCs. Impulsivity in SAs was associated with lower ACC and presupplementary motor area activity compared with HCs, and related to both ventral (amygdala, ventrolateral PFC, insula) and dorsal (dorsolateral PFC, dorsal ACC, posterior parietal cortex) systems. Decision making in SAs was associated with low dorsolateral PFC activity and high orbitofrontal activity. Finally, executive function in SAs was associated with lower activation in frontotemporal regions and higher activation in premotor cortex compared with HCs. It is concluded that the lower activations compared with HCs are likely to reflect the neural substrate of impaired neurocognitive functions, whereas higher activations in SAs compared with HCs are likely to reflect compensatory cognitive control mechanisms to keep behavioral task performance to a similar level as in HCs. However, before final conclusions can be drawn, additional research is needed using neuroimaging in SAs and HCs using larger and more homogeneous samples as well as more comparable task paradigms, study designs, and statistical analyses. PMID:22950052

  9. Anatomical and functional neuroimaging in awake, behaving marmosets.

    PubMed

    Silva, Afonso C

    2017-03-01

    The common marmoset (Callithrix jacchus) is a small New World monkey that has gained significant recent interest in neuroscience research, not only because of its compatibility with gene editing techniques, but also due to its tremendous versatility as an experimental animal model. Neuroimaging modalities, including anatomical (MRI) and functional magnetic resonance imaging (fMRI), complemented by two-photon laser scanning microscopy and electrophysiology, have been at the forefront of unraveling the anatomical and functional organization of the marmoset brain. High-resolution anatomical MRI of the marmoset brain can be obtained with remarkable cytoarchitectonic detail. Functional MRI of the marmoset brain has been used to study various sensory systems, including somatosensory, auditory, and visual pathways, while resting-state fMRI studies have unraveled functional brain networks that bear great correspondence to those previously described in humans. Two-photon laser scanning microscopy of the marmoset brain has enabled the simultaneous recording of neuronal activity from thousands of neurons with single cell spatial resolution. In this article, we aim to review the main results obtained by our group and by our colleagues in applying neuroimaging techniques to study the marmoset brain. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 373-389, 2017.

  10. Cholinergic modulation of cognition: Insights from human pharmacological functional neuroimaging

    PubMed Central

    Bentley, Paul; Driver, Jon; Dolan, Raymond J.

    2011-01-01

    Evidence from lesion and cortical-slice studies implicate the neocortical cholinergic system in the modulation of sensory, attentional and memory processing. In this review we consider findings from sixty-three healthy human cholinergic functional neuroimaging studies that probe interactions of cholinergic drugs with brain activation profiles, and relate these to contemporary neurobiological models. Consistent patterns that emerge are: (1) the direction of cholinergic modulation of sensory cortex activations depends upon top-down influences; (2) cholinergic hyperstimulation reduces top-down selective modulation of sensory cortices; (3) cholinergic hyperstimulation interacts with task-specific frontoparietal activations according to one of several patterns, including: suppression of parietal-mediated reorienting; decreasing ‘effort’-associated activations in prefrontal regions; and deactivation of a ‘resting-state network’ in medial cortex, with reciprocal recruitment of dorsolateral frontoparietal regions during performance-challenging conditions; (4) encoding-related activations in both neocortical and hippocampal regions are disrupted by cholinergic blockade, or enhanced with cholinergic stimulation, while the opposite profile is observed during retrieval; (5) many examples exist of an ‘inverted-U shaped’ pattern of cholinergic influences by which the direction of functional neural activation (and performance) depends upon both task (e.g. relative difficulty) and subject (e.g. age) factors. Overall, human cholinergic functional neuroimaging studies both corroborate and extend physiological accounts of cholinergic function arising from other experimental contexts, while providing mechanistic insights into cholinergic-acting drugs and their potential clinical applications. PMID:21708219

  11. Functional Neuroimaging Investigations of Motor Networks in Tourette Syndrome

    PubMed Central

    Rothenberger, Aribert; Roessner, Veit

    2013-01-01

    Motor and vocal tics are the core symptom of Tourette syndrome (TS). Tic generation seems to develop throughout the known motor pathways. This review focuses on functional neuroimaging in order to check this assumption. Also it elucidates the alterations and interactions of motor networks in TS depending on different contexts and circumstances like resting state, spontaneous tic movements, suppression of tics and premonitory urges, voluntary goal-oriented movements as well as electrophysiological neuronal stimulation. In general, the primary tic generating motor network uses the basic motor pathways differently, interacts with secondary sensorimotor networks and neuronal systems of cognitive behavioural control in a merely hierarchical manner, changing during neurodevelopment. PMID:23187141

  12. Molecular neuroimaging in rodents: assessing receptor expression and function.

    PubMed

    Mueggler, Thomas; Baltes, Christof; Rudin, Markus

    2009-11-01

    Multimodal non-invasive neuroimaging in rodents constitutes an attractive tool for studying neurobiological processes in vivo. At present, imaging studies of brain anatomy and function as well as the investigation of structure-function relationships belong to the standard repertoire of neuroscientists. Molecular imaging adds a new perspective. The mapping of the receptor distribution and receptor occupancy can nowadays be complemented by specific readouts of receptor function either by visualizing the activity of signaling pathways or mapping the physiological consequences of receptor stimulation. Molecular information is obtained through the use of imaging probes that combine a target-specific ligand with a reporter moiety that generates a signal that can be detected from outside the body. For imaging probes targeting the central nervous system, penetration of the intact blood-brain barrier constitutes a major hurdle. Molecular imaging generates specific information and therefore has a large potential for disease phenotyping (diagnostics), therapy development and monitoring of treatment response. Molecular imaging is still in its infancy and major developments in imaging technology, probe design and data analysis are required in order to make an impact. Rodent molecular neuroimaging will play an important role in the development of these tools.

  13. Neuronal oscillations in sleep: insights from functional neuroimaging.

    PubMed

    Dang-Vu, Thien Thanh

    2012-09-01

    Recent functional neuroimaging studies have investigated brain activity patterns during sleep in humans, beyond the conventionally defined sleep stages. These works have characterized the neural activations related to the major brain oscillations of sleep, that is, spindles and slow waves during non-rapid-eye-movement sleep and ponto-geniculo-occipital waves during rapid-eye-movement sleep. These phasic events have been found associated with increases of brain activity in specific neural networks, which identify structures involved in the generation of sleep oscillations. Most importantly, these results confirm that, even during the deepest stages of sleep, neuronal network activities are sustained and organized by spontaneous brain oscillations of sleep. The understanding of the neural mechanisms underlying sleep oscillations is fundamental since increasing evidence suggests a pivotal role for these rhythms in the functional properties of sleep. In particular, interactions between the sleeping brain and the surrounding environment are closely modulated by neuronal oscillations of sleep. Functional neuroimaging studies have demonstrated that spindles distort the transmission of auditory information to the cortex, therefore isolating the brain from external disturbances during sleep. In contrast, slow waves evoked by acoustic stimulation--and also termed K-complexes--are associated with larger auditory cortex activation, thus reflecting an enhanced processing of external information during sleep. Future brain imaging studies of sleep should further explore the contribution of neuronal oscillations to the off-line consolidation of memory during sleep.

  14. Brain images, babies, and bathwater: critiquing critiques of functional neuroimaging.

    PubMed

    Farah, Martha J

    2014-01-01

    Since the mid-1980s, psychologists and neuroscientists have used brain imaging to test hypotheses about human thought processes and their neural instantiation. In just three decades, functional neuroimaging has been transformed from a crude clinical tool to a widely used research method for understanding the human brain and mind. Such rapidly achieved success is bound to evoke skepticism. A degree of skepticism toward new methods and ideas is both inevitable and useful in any field. It is especially valuable in a science as young as cognitive neuroscience and its even younger siblings, social and affective neuroscience. Healthy skepticism encourages us to check our assumptions, recognize the limitations of our methods, and proceed thoughtfully. Skepticism itself, however, also must be examined. In this article, I review the most commonly voiced criticisms of functional neuroimaging. In the spirit of healthy skepticism, I will critically examine these criticisms themselves. Each contains at least a kernel of truth, although I will argue that in some cases the kernel has been over extended in ways that are inaccurate or misleading.

  15. On the role of general system theory for functional neuroimaging

    PubMed Central

    Stephan, Klaas Enno

    2004-01-01

    One of the most important goals of neuroscience is to establish precise structure–function relationships in the brain. Since the 19th century, a major scientific endeavour has been to associate structurally distinct cortical regions with specific cognitive functions. This was traditionally accomplished by correlating microstructurally defined areas with lesion sites found in patients with specific neuropsychological symptoms. Modern neuroimaging techniques with high spatial resolution have promised an alternative approach, enabling non-invasive measurements of regionally specific changes of brain activity that are correlated with certain components of a cognitive process. Reviewing classic approaches towards brain structure–function relationships that are based on correlational approaches, this article argues that these approaches are not sufficient to provide an understanding of the operational principles of a dynamic system such as the brain but must be complemented by models based on general system theory. These models reflect the connectional structure of the system under investigation and emphasize context-dependent couplings between the system elements in terms of effective connectivity. The usefulness of system models whose parameters are fitted to measured functional imaging data for testing hypotheses about structure–function relationships in the brain and their potential for clinical applications is demonstrated by several empirical examples. PMID:15610393

  16. Can Emotional and Behavioral Dysregulation in Youth Be Decoded from Functional Neuroimaging?

    PubMed Central

    Portugal, Liana C. L.; Rosa, Maria João; Rao, Anil; Bebko, Genna; Bertocci, Michele A.; Hinze, Amanda K.; Bonar, Lisa; Almeida, Jorge R. C.; Perlman, Susan B.; Versace, Amelia; Schirda, Claudiu; Travis, Michael; Gill, Mary Kay; Demeter, Christine; Diwadkar, Vaibhav A.; Ciuffetelli, Gary; Rodriguez, Eric; Forbes, Erika E.; Sunshine, Jeffrey L.; Holland, Scott K.; Kowatch, Robert A.; Birmaher, Boris; Axelson, David; Horwitz, Sarah M.; Arnold, Eugene L.; Fristad, Mary A.; Youngstrom, Eric A.; Findling, Robert L.; Pereira, Mirtes; Oliveira, Leticia; Phillips, Mary L.; Mourao-Miranda, Janaina

    2016-01-01

    Introduction High comorbidity among pediatric disorders characterized by behavioral and emotional dysregulation poses problems for diagnosis and treatment, and suggests that these disorders may be better conceptualized as dimensions of abnormal behaviors. Furthermore, identifying neuroimaging biomarkers related to dimensional measures of behavior may provide targets to guide individualized treatment. We aimed to use functional neuroimaging and pattern regression techniques to determine whether patterns of brain activity could accurately decode individual-level severity on a dimensional scale measuring behavioural and emotional dysregulation at two different time points. Methods A sample of fifty-seven youth (mean age: 14.5 years; 32 males) was selected from a multi-site study of youth with parent-reported behavioral and emotional dysregulation. Participants performed a block-design reward paradigm during functional Magnetic Resonance Imaging (fMRI). Pattern regression analyses consisted of Relevance Vector Regression (RVR) and two cross-validation strategies implemented in the Pattern Recognition for Neuroimaging toolbox (PRoNTo). Medication was treated as a binary confounding variable. Decoded and actual clinical scores were compared using Pearson’s correlation coefficient (r) and mean squared error (MSE) to evaluate the models. Permutation test was applied to estimate significance levels. Results Relevance Vector Regression identified patterns of neural activity associated with symptoms of behavioral and emotional dysregulation at the initial study screen and close to the fMRI scanning session. The correlation and the mean squared error between actual and decoded symptoms were significant at the initial study screen and close to the fMRI scanning session. However, after controlling for potential medication effects, results remained significant only for decoding symptoms at the initial study screen. Neural regions with the highest contribution to the pattern

  17. Functional neuroimaging for addiction medicine: From mechanisms to practical considerations.

    PubMed

    Ekhtiari, Hamed; Faghiri, Ashkan; Oghabian, Mohammad-Ali; Paulus, Martin P

    2016-01-01

    During last 20 years, neuroimaging with functional magnetic resonance imaging (fMRI) in people with drug addictions has introduced a wide range of quantitative biomarkers from brain's regional or network level activities during different cognitive functions. These quantitative biomarkers could be potentially used for assessment, planning, prediction, and monitoring for "addiction medicine" during screening, acute intoxication, admission to a program, completion of an acute program, admission to a long-term program, and postgraduation follow-up. In this chapter, we have briefly reviewed main neurocognitive targets for fMRI studies associated with addictive behaviors, main study types using fMRI among drug dependents, and potential applications for fMRI in addiction medicine. Main challenges and limitations for extending fMRI studies and evidences aiming at clinical applications in addiction medicine are also discussed. There is still a significant gap between available evidences from group-based fMRI studies and personalized decisions during daily practices in addiction medicine. It will be important to fill this gap with large-scale clinical trials and longitudinal studies using fMRI measures with a well-defined strategic plan for the future.

  18. Localization of function in anterior cingulate cortex: from psychosurgery to functional neuroimaging.

    PubMed

    Gasquoine, Philip Gerard

    2013-03-01

    Early localizationists linked anterior cingulate cortex (ACC: Brodmann's area 24 and adjacent regions) with emotional behavior, paving the way for bilateral cingulotomy psychosurgery in severe, treatment resistant, cases of obsessive-compulsive disorder, chronic pain, depression, and substance abuse. Neuropsychological follow-up of such cases demonstrated executive function impairment. Abnormal neuroimaged activity in ACC has been found in many psychiatric conditions, including obsessive-compulsive disorder, chronic pain, substance abuse, and schizophrenia. With healthy participants, increased neuroimaged activity in ACC has been linked with challenging executive function tasks, homeostatically incongruous physical states, and the encoding of the pleasant/averseness of stimuli. There is disagreement on the cortical substrate subsumed by the term ACC, the existence of functionally distinct ACC subregions (e.g., dorsal: cognitive vs. ventral: emotion), and the interpretation of functional neuroimaging studies. Synthesis of neuropsychological and functional neuroimaging studies suggests ACC contributes to behavior by modifying responses especially in reaction to challenging cognitive and physical states that require additional effortful cognitive control. This is accomplished by monitoring the emotional salience of stimuli, exerting control over the autonomic nervous system, and modulating cognitive activity.

  19. Functional neuroimaging insights into the physiology of human sleep.

    PubMed

    Dang-Vu, Thien Thanh; Schabus, Manuel; Desseilles, Martin; Sterpenich, Virginie; Bonjean, Maxime; Maquet, Pierre

    2010-12-01

    Functional brain imaging has been used in humans to noninvasively investigate the neural mechanisms underlying the generation of sleep stages. On the one hand, REM sleep has been associated with the activation of the pons, thalamus, limbic areas, and temporo-occipital cortices, and the deactivation of prefrontal areas, in line with theories of REM sleep generation and dreaming properties. On the other hand, during non-REM (NREM) sleep, decreases in brain activity have been consistently found in the brainstem, thalamus, and in several cortical areas including the medial prefrontal cortex (MPFC), in agreement with a homeostatic need for brain energy recovery. Benefiting from a better temporal resolution, more recent studies have characterized the brain activations related to phasic events within specific sleep stages. In particular, they have demonstrated that NREM sleep oscillations (spindles and slow waves) are indeed associated with increases in brain activity in specific subcortical and cortical areas involved in the generation or modulation of these waves. These data highlight that, even during NREM sleep, brain activity is increased, yet regionally specific and transient. Besides refining the understanding of sleep mechanisms, functional brain imaging has also advanced the description of the functional properties of sleep. For instance, it has been shown that the sleeping brain is still able to process external information and even detect the pertinence of its content. The relationship between sleep and memory has also been refined using neuroimaging, demonstrating post-learning reactivation during sleep, as well as the reorganization of memory representation on the systems level, sometimes with long-lasting effects on subsequent memory performance. Further imaging studies should focus on clarifying the role of specific sleep patterns for the processing of external stimuli, as well as the consolidation of freshly encoded information during sleep.

  20. Identification of neural targets for the treatment of psychiatric disorders: the role of functional neuroimaging.

    PubMed

    Vago, David R; Epstein, Jane; Catenaccio, Eva; Stern, Emily

    2011-04-01

    Neurosurgical treatment of psychiatric disorders has been influenced by evolving neurobiological models of symptom generation. The advent of functional neuroimaging and advances in the neurosciences have revolutionized understanding of the functional neuroanatomy of psychiatric disorders. This article reviews neuroimaging studies of depression from the last 3 decades and describes an emerging neurocircuitry model of mood disorders, focusing on critical circuits of cognition and emotion, particularly those networks involved in the regulation of evaluative, expressive and experiential aspects of emotion. The relevance of this model for neurotherapeutics is discussed, as well as the role of functional neuroimaging of psychiatric disorders.

  1. Commentary: Applications of functional neuroimaging to civil litigation of mild traumatic brain injury.

    PubMed

    Granacher, Robert P

    2008-01-01

    The current definition of mild traumatic brain injury (MTBI) is in flux. Presently, there are at least three working definitions of this disorder in the United States, with no clear consensus. Functional neuroimaging, such as single photon emission computed tomography (SPECT) and positron emission tomography (PET), initially showed promise in their ability to improve the diagnostic credibility of MTBI. Over the past decade, that promise has not been fulfilled and there is a paucity of quality studies or standards for the application of functional neuroimaging to traumatic brain injury, particularly in litigation. The legal profession is ahead of the science in this matter. The emergence of neurolaw is driving a growing use of functional neuroimaging, as a sole imaging modality, used by lawyers in an attempt to prove MTBI at trial. The medical literature on functional neuroimaging and its applications to MTBI is weak scientifically, sparse in quality publications, lacking in well-designed controlled studies, and currently does not meet the complete standards of Daubert v. Merrell Dow Pharmaceuticals, Inc., for introduction of scientific evidence at trial. At the present time, there is a clear lack of clinical correlation between functional neuroimaging of MTBI and behavioral, neuropsychological, or structural neuroimaging deficits. The use of SPECT or PET, without concurrent clinical correlation with structural neuroimaging (CT or MRI), is not recommended to be offered as evidence of MTBI in litigation.

  2. Differentiating emotional processing and attention in psychopathy with functional neuroimaging.

    PubMed

    Anderson, Nathaniel E; Steele, Vaughn R; Maurer, J Michael; Rao, Vikram; Koenigs, Michael R; Decety, Jean; Kosson, David S; Calhoun, Vince D; Kiehl, Kent A

    2017-01-16

    Individuals with psychopathy are often characterized by emotional processing deficits, and recent research has examined the specific contexts and cognitive mechanisms that underlie these abnormalities. Some evidence suggests that abnormal features of attention are fundamental to emotional deficits in persons with psychopathy, but few studies have demonstrated the neural underpinnings responsible for such effects. Here, we use functional neuroimaging to examine attention-emotion interactions among incarcerated individuals (n = 120) evaluated for psychopathic traits using the Hare Psychopathy Checklist-Revised (PCL-R). Using a task designed to manipulate attention to emotional features of visual stimuli, we demonstrate effects representing implicit emotional processing, explicit emotional processing, attention-facilitated emotional processing, and vigilance for emotional content. Results confirm the importance of considering mechanisms of attention when evaluating emotional processing differences related to psychopathic traits. The affective-interpersonal features of psychopathy (PCL-R Factor 1) were associated with relatively lower emotion-dependent augmentation of activity in visual processing areas during implicit emotional processing, while antisocial-lifestyle features (PCL-R Factor 2) were associated with elevated activity in the amygdala and related salience network regions. During explicit emotional processing, psychopathic traits were associated with upregulation in the medial prefrontal cortex, insula, and superior frontal regions. Isolating the impact of explicit attention to emotional content, only Factor 1 was related to upregulation of activity in the visual processing stream, which was accompanied by increased activity in the angular gyrus. These effects highlight some important mechanisms underlying abnormal features of attention and emotional processing that accompany psychopathic traits.

  3. Functional neuroimaging of human vocalizations and affective speech.

    PubMed

    Frühholz, Sascha; Sander, David; Grandjean, Didier

    2014-12-01

    Neuroimaging studies have verified the important integrative role of the basal ganglia during affective vocalizations. They, however, also point to additional regions supporting vocal monitoring, auditory-motor feedback processing, and online adjustments of vocal motor responses. For the case of affective vocalizations, we suggest partly extending the model to fully consider the link between primate-general and human-specific neural components.

  4. Convergent Functional Architecture of the Superior Parietal Lobule Unraveled with Multimodal Neuroimaging Approaches

    PubMed Central

    Wang, Jiaojian; Yang, Yong; Fan, Lingzhong; Xu, Jinping; Li, Changhai; Liu, Yong; Fox, Peter T.; Eickhoff, Simon B.; Yu, Chunshui; Jiang, Tianzi

    2014-01-01

    The superior parietal lobule (SPL) plays a pivotal role in many cognitive, perceptive and motor-related processes. This implies that a mosaic of distinct functional and structural subregions may exist in this area. Recent studies have demonstrated that the ongoing spontaneous fluctuations in the brain at rest are highly structured and, like co-activation patterns, reflect the integration of cortical locations into long-distance networks. This suggests that the internal differentiation of a complex brain region may be revealed by interaction-patterns that are reflected in different neuroimaging modalities. On the basis of this perspective, we aimed to identify a convergent functional organization of the SPL using multimodal neuroimaging approaches. The SPL was first parcellated based on its structural connections as well as on its resting-state connectivity and coactivation patterns. Then, post-hoc functional characterizations and connectivity analyses were performed for each subregion. The three types of connectivity-based parcellations consistently identified five subregions in the SPL of each hemisphere. The two anterior subregions were found to be primarily involved in action processes and in visually guided visuomotor functions, whereas the three posterior subregions were primarily associated with visual perception, spatial cognition, reasoning, working memory, and attention. This parcellation scheme for the SPL was further supported by revealing distinct connectivity patterns for each sub-region in all the employed modalities. These results thus indicate a convergent functional architecture of the SPL that can be revealed based on different types of connectivity and is reflected by different functions and interactions. PMID:25181023

  5. Structural brain network constrained neuroimaging marker identification for predicting cognitive functions.

    PubMed

    De, Wang; Nie, Feiping; Huang, Heng; Yan, Jingwen; Risacher, Shannon L; Saykin, Andrew J; Shen, Li

    2013-01-01

    Neuroimaging markers have been widely used to predict the cognitive functions relevant to the progression of Alzheimer's disease (AD). Most previous studies identify the imaging markers without considering the brain structural correlations between neuroimaging measures. However, many neuroimaging markers interrelate and work together to reveal the cognitive functions, such that these relevant markers should be selected together as the phenotypic markers. To solve this problem, in this paper, we propose a novel network constrained feature selection (NCFS) model to identify the neuroimaging markers guided by the structural brain network, which is constructed by the sparse representation method such that the interrelations between neuroimaging features are encoded into probabilities. Our new methods are evaluated by the MRI and AV45-PET data from ADNI-GO and ADNI-2 (Alzheimer's Disease Neuroimaging Initiative). In all cognitive function prediction tasks, our new NCFS method outperforms other state-of-the-art regression approaches. Meanwhile, we show that the new method can select the correlated imaging markers, which are ignored by the competing approaches.

  6. Design of a novel biomedical signal processing and analysis tool for functional neuroimaging.

    PubMed

    Kaçar, Sezgin; Sakoğlu, Ünal

    2016-03-01

    In this paper, a MATLAB-based graphical user interface (GUI) software tool for general biomedical signal processing and analysis of functional neuroimaging data is introduced. Specifically, electroencephalography (EEG) and electrocardiography (ECG) signals can be processed and analyzed by the developed tool, which incorporates commonly used temporal and frequency analysis methods. In addition to common methods, the tool also provides non-linear chaos analysis with Lyapunov exponents and entropies; multivariate analysis with principal and independent component analyses; and pattern classification with discriminant analysis. This tool can also be utilized for training in biomedical engineering education. This easy-to-use and easy-to-learn, intuitive tool is described in detail in this paper.

  7. Prediction of children's reading skills using behavioral, functional, and structural neuroimaging measures.

    PubMed

    Hoeft, Fumiko; Ueno, Takefumi; Reiss, Allan L; Meyler, Ann; Whitfield-Gabrieli, Susan; Glover, Gary H; Keller, Timothy A; Kobayashi, Nobuhisa; Mazaika, Paul; Jo, Booil; Just, Marcel Adam; Gabrieli, John D E

    2007-06-01

    The ability to decode letters into language sounds is essential for reading success, and accurate identification of children at high risk for decoding impairment is critical for reducing the frequency and severity of reading impairment. We examined the utility of behavioral (standardized tests), and functional and structural neuroimaging measures taken with children at the beginning of a school year for predicting their decoding ability at the end of that school year. Specific patterns of brain activation during phonological processing and morphology, as revealed by voxel-based morphometry (VBM) of gray and white matter densities, predicted later decoding ability. Further, a model combining behavioral and neuroimaging measures predicted decoding outcome significantly better than either behavioral or neuroimaging models alone. Results were validated using cross-validation methods. These findings suggest that neuroimaging methods may be useful in enhancing the early identification of children at risk for poor decoding and reading skills.

  8. Functional neuroimaging: a brief overview and feasibility for use in chiropractic research

    PubMed Central

    Lystad, Reidar P; Pollard, Henry

    2009-01-01

    There is a need to further our understanding of the neurophysiological effects of chiropractic spinal manipulation on brain activity as it pertains to both musculoskeletal and non-musculoskeletal complaints. This paper aims to provide a basic overview of the most commonly utilised techniques in the neurosciences for functional imaging the brain (positron emission tomography, single-photon emission computerised tomography, functional magnetic resonance imaging, electroencephalography, and magnetoencephalography), and discuss their applicability in future chiropractic research. Functional neuroimaging modalities are used in a wide range of different research and clinical settings, and are powerful tools in the investigation of neuronal activity in the human brain. There are many potential applications for functional neuroimaging in future chiropractic research, but there are some feasibility issues, mainly pertaining to access and funding. We strongly encourage the use of functional neuroimaging in future investigations of the effects of chiropractic spinal manipulation on brain function. PMID:19421353

  9. Overcoming the effects of false positives and threshold bias in graph theoretical analyses of neuroimaging data

    PubMed Central

    Drakesmith, M.; Caeyenberghs, K.; Dutt, A.; Lewis, G.; David, A.S.; Jones, D.K.

    2015-01-01

    Graph theory (GT) is a powerful framework for quantifying topological features of neuroimaging-derived functional and structural networks. However, false positive (FP) connections arise frequently and influence the inferred topology of networks. Thresholding is often used to overcome this problem, but an appropriate threshold often relies on a priori assumptions, which will alter inferred network topologies. Four common network metrics (global efficiency, mean clustering coefficient, mean betweenness and smallworldness) were tested using a model tractography dataset. It was found that all four network metrics were significantly affected even by just one FP. Results also show that thresholding effectively dampens the impact of FPs, but at the expense of adding significant bias to network metrics. In a larger number (n = 248) of tractography datasets, statistics were computed across random group permutations for a range of thresholds, revealing that statistics for network metrics varied significantly more than for non-network metrics (i.e., number of streamlines and number of edges). Varying degrees of network atrophy were introduced artificially to half the datasets, to test sensitivity to genuine group differences. For some network metrics, this atrophy was detected as significant (p < 0.05, determined using permutation testing) only across a limited range of thresholds. We propose a multi-threshold permutation correction (MTPC) method, based on the cluster-enhanced permutation correction approach, to identify sustained significant effects across clusters of thresholds. This approach minimises requirements to determine a single threshold a priori. We demonstrate improved sensitivity of MTPC-corrected metrics to genuine group effects compared to an existing approach and demonstrate the use of MTPC on a previously published network analysis of tractography data derived from a clinical population. In conclusion, we show that there are large biases and instability

  10. Reading the Freudian theory of sexual drives from a functional neuroimaging perspective

    PubMed Central

    Stoléru, Serge

    2014-01-01

    One of the essential tasks of neuropsychoanalysis is to investigate the neural correlates of sexual drives. Here, we consider the four defining characteristics of sexual drives as delineated by Freud: their pressure, aim, object, and source. We systematically examine the relations between these characteristics and the four-component neurophenomenological model that we have proposed based on functional neuroimaging studies, which comprises a cognitive, a motivational, an emotional and an autonomic/neuroendocrine component. Functional neuroimaging studies of sexual arousal (SA) have thrown a new light on the four fundamental characteristics of sexual drives by identifying their potential neural correlates. While these studies are essentially consistent with the Freudian model of drives, the main difference emerging between the functional neuroimaging perspective on sexual drives and the Freudian theory relates to the source of drives. From a functional neuroimaging perspective, sources of sexual drives, conceived by psychoanalysis as processes of excitation occurring in a peripheral organ, do not seem, at least in adult subjects, to be an essential part of the determinants of SA. It is rather the central processing of visual or genital stimuli that gives to these stimuli their sexually arousing and sexually pleasurable character. Finally, based on functional neuroimaging results, some possible improvements to the psychoanalytic theory of sexual drives are suggested. PMID:24672467

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

    PubMed Central

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

    2009-01-01

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

  12. [Functional neuroimaging in the diagnosis of patients with Parkinsonism: Update and recommendations for clinical use].

    PubMed

    Arbizu, J; Luquin, M R; Abella, J; de la Fuente-Fernández, R; Fernandez-Torrón, R; García-Solís, D; Garrastachu, P; Jiménez-Hoyuela, J M; Llaneza, M; Lomeña, F; Lorenzo-Bosquet, C; Martí, M J; Martinez-Castrillo, J C; Mir, P; Mitjavila, M; Ruiz-Martínez, J; Vela, L

    2014-01-01

    Functional Neuroimaging has been traditionally used in research for patients with different Parkinsonian syndromes. However, the emergence of commercial radiotracers together with the availability of single photon emission computed tomography (SPECT) and, more recently, positron emission tomography (PET) have made them available for clinical practice. Particularly, the development of clinical evidence achieved by functional neuroimaging techniques over the past two decades have motivated a progressive inclusion of several biomarkers in the clinical diagnostic criteria for neurodegenerative diseases that occur with Parkinsonism. However, the wide range of radiotracers designed to assess the involvement of different pathways in the neurodegenerative process underlying Parkinsonian syndromes (dopaminergic nigrostriatal pathway integrity, basal ganglia and cortical neuronal activity, myocardial sympathetic innervation), and the different neuroimaging techniques currently available (scintigraphy, SPECT and PET), have generated some controversy concerning the best neuroimaging test that should be indicated for the differential diagnosis of Parkinsonism. In this article, a panel of nuclear medicine and neurology experts has evaluated the functional neuroimaging techniques emphazising practical considerations related to the diagnosis of patients with uncertain origin parkinsonism and the assessment Parkinson's disease progression.

  13. Functional neuroimaging of duration discrimination on two different time scales.

    PubMed

    Gutyrchik, Evgeny; Churan, Jan; Meindl, Thomas; Bokde, Arun Lawrence Warren; von Bernewitz, Henriette; Born, Christine; Reiser, Maximilian; Pöppel, Ernst; Wittmann, Marc

    2010-01-29

    Analyses of neural mechanisms of duration processing are essential for the understanding of psychological phenomena which evolve in time. Different mechanisms are presumably responsible for the processing of shorter (below 500 ms) and longer (above 500 ms) events but have not yet been a subject of an investigation with functional magnetic resonance imaging (fMRI). In the present study, we show a greater involvement of several brain regions - including right-hemispheric midline structures and left-hemispheric lateral regions - in the processing of visual stimuli of shorter as compared to longer duration. We propose a greater involvement of lower-level cognitive mechanisms in the processing of shorter events as opposed to higher-level mechanisms of cognitive control involved in longer events.

  14. The ENIGMA Consortium: large-scale collaborative analyses of neuroimaging and genetic data.

    PubMed

    Thompson, Paul M; Stein, Jason L; Medland, Sarah E; Hibar, Derrek P; Vasquez, Alejandro Arias; Renteria, Miguel E; Toro, Roberto; Jahanshad, Neda; Schumann, Gunter; Franke, Barbara; Wright, Margaret J; Martin, Nicholas G; Agartz, Ingrid; Alda, Martin; Alhusaini, Saud; Almasy, Laura; Almeida, Jorge; Alpert, Kathryn; Andreasen, Nancy C; Andreassen, Ole A; Apostolova, Liana G; Appel, Katja; Armstrong, Nicola J; Aribisala, Benjamin; Bastin, Mark E; Bauer, Michael; Bearden, Carrie E; Bergmann, Orjan; Binder, Elisabeth B; Blangero, John; Bockholt, Henry J; Bøen, Erlend; Bois, Catherine; Boomsma, Dorret I; Booth, Tom; Bowman, Ian J; Bralten, Janita; Brouwer, Rachel M; Brunner, Han G; Brohawn, David G; Buckner, Randy L; Buitelaar, Jan; Bulayeva, Kazima; Bustillo, Juan R; Calhoun, Vince D; Cannon, Dara M; Cantor, Rita M; Carless, Melanie A; Caseras, Xavier; Cavalleri, Gianpiero L; Chakravarty, M Mallar; Chang, Kiki D; Ching, Christopher R K; Christoforou, Andrea; Cichon, Sven; Clark, Vincent P; Conrod, Patricia; Coppola, Giovanni; Crespo-Facorro, Benedicto; Curran, Joanne E; Czisch, Michael; Deary, Ian J; de Geus, Eco J C; den Braber, Anouk; Delvecchio, Giuseppe; Depondt, Chantal; de Haan, Lieuwe; de Zubicaray, Greig I; Dima, Danai; Dimitrova, Rali; Djurovic, Srdjan; Dong, Hongwei; Donohoe, Gary; Duggirala, Ravindranath; Dyer, Thomas D; Ehrlich, Stefan; Ekman, Carl Johan; Elvsåshagen, Torbjørn; Emsell, Louise; Erk, Susanne; Espeseth, Thomas; Fagerness, Jesen; Fears, Scott; Fedko, Iryna; Fernández, Guillén; Fisher, Simon E; Foroud, Tatiana; Fox, Peter T; Francks, Clyde; Frangou, Sophia; Frey, Eva Maria; Frodl, Thomas; Frouin, Vincent; Garavan, Hugh; Giddaluru, Sudheer; Glahn, David C; Godlewska, Beata; Goldstein, Rita Z; Gollub, Randy L; Grabe, Hans J; Grimm, Oliver; Gruber, Oliver; Guadalupe, Tulio; Gur, Raquel E; Gur, Ruben C; Göring, Harald H H; Hagenaars, Saskia; Hajek, Tomas; Hall, Geoffrey B; Hall, Jeremy; Hardy, John; Hartman, Catharina A; Hass, Johanna; Hatton, Sean N; Haukvik, Unn K; Hegenscheid, Katrin; Heinz, Andreas; Hickie, Ian B; Ho, Beng-Choon; Hoehn, David; Hoekstra, Pieter J; Hollinshead, Marisa; Holmes, Avram J; Homuth, Georg; Hoogman, Martine; Hong, L Elliot; Hosten, Norbert; Hottenga, Jouke-Jan; Hulshoff Pol, Hilleke E; Hwang, Kristy S; Jack, Clifford R; Jenkinson, Mark; Johnston, Caroline; Jönsson, Erik G; Kahn, René S; Kasperaviciute, Dalia; Kelly, Sinead; Kim, Sungeun; Kochunov, Peter; Koenders, Laura; Krämer, Bernd; Kwok, John B J; Lagopoulos, Jim; Laje, Gonzalo; Landen, Mikael; Landman, Bennett A; Lauriello, John; Lawrie, Stephen M; Lee, Phil H; Le Hellard, Stephanie; Lemaître, Herve; Leonardo, Cassandra D; Li, Chiang-Shan; Liberg, Benny; Liewald, David C; Liu, Xinmin; Lopez, Lorna M; Loth, Eva; Lourdusamy, Anbarasu; Luciano, Michelle; Macciardi, Fabio; Machielsen, Marise W J; Macqueen, Glenda M; Malt, Ulrik F; Mandl, René; Manoach, Dara S; Martinot, Jean-Luc; Matarin, Mar; Mather, Karen A; Mattheisen, Manuel; Mattingsdal, Morten; Meyer-Lindenberg, Andreas; McDonald, Colm; McIntosh, Andrew M; McMahon, Francis J; McMahon, Katie L; Meisenzahl, Eva; Melle, Ingrid; Milaneschi, Yuri; Mohnke, Sebastian; Montgomery, Grant W; Morris, Derek W; Moses, Eric K; Mueller, Bryon A; Muñoz Maniega, Susana; Mühleisen, Thomas W; Müller-Myhsok, Bertram; Mwangi, Benson; Nauck, Matthias; Nho, Kwangsik; Nichols, Thomas E; Nilsson, Lars-Göran; Nugent, Allison C; Nyberg, Lars; Olvera, Rene L; Oosterlaan, Jaap; Ophoff, Roel A; Pandolfo, Massimo; Papalampropoulou-Tsiridou, Melina; Papmeyer, Martina; Paus, Tomas; Pausova, Zdenka; Pearlson, Godfrey D; Penninx, Brenda W; Peterson, Charles P; Pfennig, Andrea; Phillips, Mary; Pike, G Bruce; Poline, Jean-Baptiste; Potkin, Steven G; Pütz, Benno; Ramasamy, Adaikalavan; Rasmussen, Jerod; Rietschel, Marcella; Rijpkema, Mark; Risacher, Shannon L; Roffman, Joshua L; Roiz-Santiañez, Roberto; Romanczuk-Seiferth, Nina; Rose, Emma J; Royle, Natalie A; Rujescu, Dan; Ryten, Mina; Sachdev, Perminder S; Salami, Alireza; Satterthwaite, Theodore D; Savitz, Jonathan; Saykin, Andrew J; Scanlon, Cathy; Schmaal, Lianne; Schnack, Hugo G; Schork, Andrew J; Schulz, S Charles; Schür, Remmelt; Seidman, Larry; Shen, Li; Shoemaker, Jody M; Simmons, Andrew; Sisodiya, Sanjay M; Smith, Colin; Smoller, Jordan W; Soares, Jair C; Sponheim, Scott R; Sprooten, Emma; Starr, John M; Steen, Vidar M; Strakowski, Stephen; Strike, Lachlan; Sussmann, Jessika; Sämann, Philipp G; Teumer, Alexander; Toga, Arthur W; Tordesillas-Gutierrez, Diana; Trabzuni, Daniah; Trost, Sarah; Turner, Jessica; Van den Heuvel, Martijn; van der Wee, Nic J; van Eijk, Kristel; van Erp, Theo G M; van Haren, Neeltje E M; van 't Ent, Dennis; van Tol, Marie-Jose; Valdés Hernández, Maria C; Veltman, Dick J; Versace, Amelia; Völzke, Henry; Walker, Robert; Walter, Henrik; Wang, Lei; Wardlaw, Joanna M; Weale, Michael E; Weiner, Michael W; Wen, Wei; Westlye, Lars T; Whalley, Heather C; Whelan, Christopher D; White, Tonya; Winkler, Anderson M; Wittfeld, Katharina; Woldehawariat, Girma; Wolf, Christiane; Zilles, David; Zwiers, Marcel P; Thalamuthu, Anbupalam; Schofield, Peter R; Freimer, Nelson B; Lawrence, Natalia S; Drevets, Wayne

    2014-06-01

    The Enhancing NeuroImaging Genetics through Meta-Analysis (ENIGMA) Consortium is a collaborative network of researchers working together on a range of large-scale studies that integrate data from 70 institutions worldwide. Organized into Working Groups that tackle questions in neuroscience, genetics, and medicine, ENIGMA studies have analyzed neuroimaging data from over 12,826 subjects. In addition, data from 12,171 individuals were provided by the CHARGE consortium for replication of findings, in a total of 24,997 subjects. By meta-analyzing results from many sites, ENIGMA has detected factors that affect the brain that no individual site could detect on its own, and that require larger numbers of subjects than any individual neuroimaging study has currently collected. ENIGMA's first project was a genome-wide association study identifying common variants in the genome associated with hippocampal volume or intracranial volume. Continuing work is exploring genetic associations with subcortical volumes (ENIGMA2) and white matter microstructure (ENIGMA-DTI). Working groups also focus on understanding how schizophrenia, bipolar illness, major depression and attention deficit/hyperactivity disorder (ADHD) affect the brain. We review the current progress of the ENIGMA Consortium, along with challenges and unexpected discoveries made on the way.

  15. Neural dichotomy of word concreteness: a view from functional neuroimaging.

    PubMed

    Kumar, Uttam

    2016-02-01

    Our perception about the representation and processing of concrete and abstract concepts is based on the fact that concrete words are highly imagined and remembered faster than abstract words. In order to explain the processing differences between abstract and concrete concepts, various theories have been proposed, yet there is no unanimous consensus about its neural implication. The present study investigated the processing of concrete and abstract words during an orthography judgment task (implicit semantic processing) using functional magnetic resonance imaging to validate the involvement of the neural regions. Relative to non-words, both abstract and concrete words show activation in the regions of bilateral hemisphere previously associated with semantic processing. The common areas (conjunction analyses) observed for abstract and concrete words are bilateral inferior frontal gyrus (BA 44/45), left superior parietal (BA 7), left fusiform gyrus and bilateral middle occipital. The additional areas for abstract words were noticed in bilateral superior temporal and bilateral middle temporal region, whereas no distinct region was noticed for concrete words. This suggests that words with abstract concepts recruit additional language regions in the brain.

  16. NIFTY (NeuroImaging Functional Toolkit): an interactive program for functional MRI data processing and visualization

    NASA Astrophysics Data System (ADS)

    Arnholt, Jeff C.; Hanson, Dennis P.; Robb, Richard A.

    1995-05-01

    NIFTY (NeuroImaging Functional Toolkit) is a tool designed to perform quantitative analysis and visualization of neurofunctional magnetic resonance image (fMRI) data sets. NIFTY is an OSF/Motif application which utilizes the AVW (a visualization workshop) imaging library developed in our laboratory and includes algorithms for robust image registration, statistical analysis, and mapping of neurofunctional data sets. Anisotropic diffusion routines can be used to enhance the signal-to-noise- ratio of these images. Tools capable of histogram equalization, thresholding, volume rendering, atlas matching, and a large number of other functions can then be used to visualize the data. NIFTY's development will offer a robust and flexible system of essential functions integrated into an interactive, graphically-oriented program, allowing neuroscientists the means by which to process, visualize, and interpret their data.

  17. Integrating Functional Brain Neuroimaging and Developmental Cognitive Neuroscience in Child Psychiatry Research

    ERIC Educational Resources Information Center

    Pavuluri, Mani N.; Sweeney, John A.

    2008-01-01

    The use of cognitive neuroscience and functional brain neuroimaging to understand brain dysfunction in pediatric psychiatric disorders is discussed. Results show that bipolar youths demonstrate impairment in affective and cognitive neural systems and in these two circuits' interface. Implications for the diagnosis and treatment of psychiatric…

  18. Systematic Review of Structural and Functional Neuroimaging Findings in Children and Adults with CKD

    PubMed Central

    Reiser, Kathryn A.; Detre, John A.; Schultz, Robert T.; Herrington, John D.; Davatzikos, Christos; Doshi, Jimit J.; Erus, Guray; Liu, Hua-Shan; Radcliffe, Jerilynn; Furth, Susan L.; Hooper, Stephen R.

    2013-01-01

    Summary CKD has been linked with cognitive deficits and affective disorders in multiple studies. Analysis of structural and functional neuroimaging in adults and children with kidney disease may provide additional important insights into the pathobiology of this relationship. This paper comprehensively reviews neuroimaging studies in both children and adults. Major databases (PsychLit, MEDLINE, WorldCat, ArticleFirst, PubMed, Ovid MEDLINE) were searched using consistent search terms, and studies published between 1975 and 2012 were included if their samples focused on CKD as the primary disease process. Exclusion criteria included case reports, chapters, and review articles. This systematic process yielded 43 studies for inclusion (30 in adults, 13 in children). Findings from this review identified several clear trends: (1) presence of cerebral atrophy and cerebral density changes in patients with CKD; (2) cerebral vascular disease, including deep white matter hyperintensities, white matter lesions, cerebral microbleeds, silent cerebral infarction, and cortical infarction, in patients with CKD; and (3) similarities in regional cerebral blood flow between patients with CKD and those with affective disorders. These findings document the importance of neuroimaging procedures in understanding the effect of CKD on brain structure, function, and associated behaviors. Results provide a developmental linkage between childhood and adulthood, with respect to the effect of CKD on brain functioning across the lifespan, with strong implications for a cerebrovascular mechanism contributing to this developmental linkage. Use of neuroimaging methods to corroborate manifest neuropsychological deficits or perhaps to indicate preventive actions may prove useful to individuals with CKD. PMID:23723341

  19. Systematic review of structural and functional neuroimaging findings in children and adults with CKD.

    PubMed

    Moodalbail, Divya G; Reiser, Kathryn A; Detre, John A; Schultz, Robert T; Herrington, John D; Davatzikos, Christos; Doshi, Jimit J; Erus, Guray; Liu, Hua-Shan; Radcliffe, Jerilynn; Furth, Susan L; Hooper, Stephen R

    2013-08-01

    CKD has been linked with cognitive deficits and affective disorders in multiple studies. Analysis of structural and functional neuroimaging in adults and children with kidney disease may provide additional important insights into the pathobiology of this relationship. This paper comprehensively reviews neuroimaging studies in both children and adults. Major databases (PsychLit, MEDLINE, WorldCat, ArticleFirst, PubMed, Ovid MEDLINE) were searched using consistent search terms, and studies published between 1975 and 2012 were included if their samples focused on CKD as the primary disease process. Exclusion criteria included case reports, chapters, and review articles. This systematic process yielded 43 studies for inclusion (30 in adults, 13 in children). Findings from this review identified several clear trends: (1) presence of cerebral atrophy and cerebral density changes in patients with CKD; (2) cerebral vascular disease, including deep white matter hyperintensities, white matter lesions, cerebral microbleeds, silent cerebral infarction, and cortical infarction, in patients with CKD; and (3) similarities in regional cerebral blood flow between patients with CKD and those with affective disorders. These findings document the importance of neuroimaging procedures in understanding the effect of CKD on brain structure, function, and associated behaviors. Results provide a developmental linkage between childhood and adulthood, with respect to the effect of CKD on brain functioning across the lifespan, with strong implications for a cerebrovascular mechanism contributing to this developmental linkage. Use of neuroimaging methods to corroborate manifest neuropsychological deficits or perhaps to indicate preventive actions may prove useful to individuals with CKD.

  20. Linking variability in brain chemistry and circuit function through multimodal human neuroimaging.

    PubMed

    Fisher, P M; Hariri, A R

    2012-08-01

    Identifying neurobiological mechanisms mediating the emergence of individual differences in behavior is critical for advancing our understanding of relative risk for psychopathology. Neuroreceptor positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) can be used to assay in vivo regional brain chemistry and function, respectively. Typically, these neuroimaging modalities are implemented independently despite the capacity for integrated data sets to offer unique insight into molecular mechanisms associated with brain function. Through examples from the serotonin and dopamine system and its effects on threat- and reward-related brain function, we review evidence for how such a multimodal neuroimaging strategy can be successfully implemented. Furthermore, we discuss how multimodal PET-fMRI can be integrated with techniques such as imaging genetics, pharmacological challenge paradigms and gene-environment interaction models to more completely map biological pathways mediating individual differences in behavior and related risk for psychopathology and inform the development of novel therapeutic targets.

  1. Neural convergence and divergence in the mammalian cerebral cortex: from experimental neuroanatomy to functional neuroimaging.

    PubMed

    Man, Kingson; Kaplan, Jonas; Damasio, Hanna; Damasio, Antonio

    2013-12-15

    A development essential for understanding the neural basis of complex behavior and cognition is the description, during the last quarter of the twentieth century, of detailed patterns of neuronal circuitry in the mammalian cerebral cortex. This effort established that sensory pathways exhibit successive levels of convergence, from the early sensory cortices to sensory-specific and multisensory association cortices, culminating in maximally integrative regions. It was also established that this convergence is reciprocated by successive levels of divergence, from the maximally integrative areas all the way back to the early sensory cortices. This article first provides a brief historical review of these neuroanatomical findings, which were relevant to the study of brain and mind-behavior relationships and to the proposal of heuristic anatomofunctional frameworks. In a second part, the article reviews new evidence that has accumulated from studies of functional neuroimaging, employing both univariate and multivariate analyses, as well as electrophysiology, in humans and other mammals, that the integration of information across the auditory, visual, and somatosensory-motor modalities proceeds in a content-rich manner. Behaviorally and cognitively relevant information is extracted from and conserved across the different modalities, both in higher order association cortices and in early sensory cortices. Such stimulus-specific information is plausibly relayed along the neuroanatomical pathways alluded to above. The evidence reviewed here suggests the need for further in-depth exploration of the intricate connectivity of the mammalian cerebral cortex in experimental neuroanatomical studies.

  2. Does Functional Neuroimaging Solve the Questions of Neurolinguistics?

    ERIC Educational Resources Information Center

    Sidtis, Diana Van Lancker

    2006-01-01

    Neurolinguistic research has been engaged in evaluating models of language using measures from brain structure and function, and/or in investigating brain structure and function with respect to language representation using proposed models of language. While the aphasiological strategy, which classifies aphasias based on performance modality and a…

  3. PET neuroimaging of extrastriatal dopamine receptors and prefrontal cortex functions.

    PubMed

    Takahashi, Hidehiko

    2013-12-01

    The role of prefrontal dopamine D1 receptors in prefrontal cortex (PFC) functions, including working memory, is widely investigated. However, human (healthy volunteers and schizophrenia patients) positron emission tomography (PET) studies about the relationship between prefrontal D1 receptors and PFC functions are somewhat inconsistent. We argued that several factors including an inverted U-shaped relationship between prefrontal D1 receptors and PFC functions might be responsible for these inconsistencies. In contrast to D1 receptors, relatively less attention has been paid to the role of D2 receptors in PFC functions. Several animal and human pharmacological studies have reported that the systemic administration of D2 receptor agonist/antagonist modulates PFC functions, although those studies do not tell us which region(s) is responsible for the effect. Furthermore, while prefrontal D1 receptors are primarily involved in working memory, other PFC functions such as set-shifting seem to be differentially modulated by dopamine. PET studies of extrastriatal D2 receptors including ours suggested that orchestration of prefrontal dopamine transmission and hippocampal dopamine transmission might be necessary for a broad range of normal PFC functions. In order to understand the complex effects of dopamine signaling on PFC functions, measuring a single index related to basic dopamine tone is not sufficient. For a better understanding of the meanings of PET indices related to neurotransmitters, comprehensive information (presynaptic, postsynaptic, and beyond receptor signaling) will be required. Still, an interdisciplinary approach combining molecular imaging techniques with cognitive neuroscience and clinical psychiatry will provide new perspectives for understanding the neurobiology of neuropsychiatric disorders and their innovative drug developments.

  4. Three key regions for supervisory attentional control: Evidence from neuroimaging meta-analyses

    PubMed Central

    Cieslik, Edna C.; Mueller, Veronika I.; Eickhoff, Claudia R.; Langner, Robert; Eickhoff, Simon B.

    2014-01-01

    The supervisory attentional system has been proposed to mediate non-routine, goal-oriented behaviour by guiding the selection and maintenance of the goal-relevant task schema. Here, we aimed to delineate the brain regions that mediate these high-level control processes via neuroimaging meta-analysis. In particular, we investigated the core neural correlates of a wide range of tasks requiring supervisory control for the suppression of a routine action in favour of another, non-routine one. Our sample comprised n = 173 experiments employing go/no-go, stop-signal, Stroop or spatial interference tasks. Consistent convergence across all four paradigm classes was restricted to right anterior insula and inferior frontal junction, with anterior midcingulate cortex and pre-supplementary motor area being consistently involved in all but the go/no-go task. Taken together with lesion studies in patients, our findings suggest that the controlled activation and maintenance of adequate task schemata relies, across paradigms, on a right-dominant midcingulo-insular-inferior frontal core network. This also implies that the role of other prefrontal and parietal regions may be less domain-general than previously thought. PMID:25446951

  5. Functional Neuroimaging of Social and Nonsocial Cognitive Control in Autism

    ERIC Educational Resources Information Center

    Sabatino, Antoinette; Rittenberg, Alison; Sasson, Noah J.; Turner-Brown, Lauren; Bodfish, James W.; Dichter, Gabriel S.

    2013-01-01

    This study investigated cognitive control of social and nonsocial information in autism using functional magnetic resonance imaging. Individuals with autism spectrum disorders (ASDs) and a neurotypical control group completed an oddball target detection task where target stimuli were either faces or nonsocial objects previously shown to be related…

  6. Medical-Legal Inferences From Functional Neuroimaging Evidence.

    PubMed

    Mayberg

    1996-07-01

    Positron emission (PET) and single-photon emission tomography (SPECT) are validated functional imaging techniques for the in vivo measurement of many neuro-phsyiological and neurochemical parameters. Research studies of patients with a broad range of neurological and psychiatric illness have been published. Reproducible and specific patterns of altered cerebral blood flow and glucose metabolism, however, have been demonstrated and confirmed for only a limited number of specific illnesses. The association of functional scan patterns with specific deficits is less conclusive. Correlations of regional abnormalities with clinical symptoms such as motor weakness, aphasia, and visual spatial dysfunction are the most reproducible but are more poorly localized than lesion-deficit studies would suggest. Findings are even less consistent for nonlocalizing behavioral symptoms such as memory difficulties, poor concentration, irritability, or chronic pain, and no reliable patterns have been demonstrated. In a forensic context, homicidal and sadistic tendencies, aberrant sexual drive, violent impulsivity, psychopathic and sociopathic personality traits, as well as impaired judgement and poor insight, have no known PET or SPECT patterns, and their presence in an individual with any PET or SPECT scan finding cannot be inferred or concluded. Furthermore, the reliable prediction of any specific neurological, psychiatric, or behavioral deficits from specific scan findings has not been demonstrated. Unambiguous results from experiments designed to specifically examine the causative relationships between regional brain dysfunction and these types of complex behaviors are needed before any introduction of functional scans into the courts can be considered scientifically justified or legally admissible.

  7. [Functional neuroimaging of the amygdala: the response to threatening and phobogenic stimuli].

    PubMed

    Del Casale, Antonio; Ferracuti, Stefano; Rapinesi, Chiara; Serata, Daniele; Simonetti, Alessio; Caloro, Matteo; Caltagirone, Saverio Simone; Brugnoli, Chiara; Kotzalidis, Giorgio D; Tatarelli, Roberto; Girardi, Paolo

    2013-01-01

    Recent functional neuroimaging studies show that the amygdala has a central role in threat evaluation, in response to conditioned and unconditioned stimuli, in fear learning and fear extinction. The amygdala is involved in the pathophysiology of phobias and anxiety. In this review we critically examine the main findings of functional neuroimaging studies reporting data on the amygdala. Findings suggest that the response of the amygdala to threatening stimuli is mainly modulated by the infralimbic and prefrontal cortices, which inhibit activation of the amygdala (top-down inhibition), and by the hippocampus, the function of which is related to stimulus learning. The activity of the amygdala is modulated by various factors, like stimulus type and origin, emotion triggered by stimulus perception, and attention. The neural network comprising the amygdala and the frontal cortex is involved not only in top-down inhibition, but also in the emotional perception of facial expressions. This network also includes the thalamic pulvinar, which is densely interconnected with the amygdala, directly or indirectly, and which is activated by emotional face recognition of scary fear. Both top-down inhibition mechanisms and emotional face recognition are altered in anxiety disorders, particularly in specific and social phobia, resulting in reduced amygdalar activity inhibition after anxiety - or fear - inducing stimulus perception. Future functional neuroimaging studies will be able to provide new insights of normal and altered neurophysiology of the amygdala.

  8. Integration of EEG/MEG with MRI and fMRI in Functional Neuroimaging

    PubMed Central

    Liu, Zhongming; Ding, Lei; He, Bin

    2007-01-01

    EEG and MEG are important functional neuroimaging modalities for studying the temporal dynamics of neural activities and interactions, but the accurate localization of neural activities still remains a challenging problem. Combining EEG/MEG with MRI or/and functional MRI (fMRI) holds promise to significantly increase the spatial resolution of electromagnetic source imaging, and at the same time, allows tracing the rapid neural processes and information pathways within the brain, which cannot be achieved using these modalities in isolation. In this paper, we review some recent progresses in multimodal neuroimaging, with special emphasis on the integration of EEG, MEG with MRI and fMRI. Some examples are shown to illustrate the importance of the combined source analysis in clinical and experimental studies. PMID:16898658

  9. Functional neuroimaging of Social and Nonsocial Cognitive Control in Autism

    PubMed Central

    Sabatino, Antoinette; Rittenberg, Alison; Sasson, Noah J.; Turner-Brown, Lauren; Bodfish, James W.; Dichter, Gabriel S.

    2013-01-01

    This study investigated cognitive control of social and nonsocial information in autism using functional magnetic resonance imaging. Individuals with autism spectrum disorders (ASDs) and a neurotypical control group completed an oddball target detection task where target stimuli were either faces or nonsocial objects previously shown to be related to circumscribed interests in autism. The ASD group demonstrated relatively increased activation to social targets in right insular cortex and in left superior frontal gyrus and relatively decreased activation to nonsocial targets related to circumscribed interests in multiple frontostriatal brain regions. Findings suggest that frontostriatal recruitment during cognitive control in ASD is contingent on stimulus type, with increased activation for social stimuli and decreased activation for nonsocial stimuli related to circumscribed interests. PMID:23636715

  10. Functional neuroimaging and schizophrenia: a view towards effective connectivity modeling and polygenic risk.

    PubMed

    Birnbaum, Rebecca; Weinberger, Daniel R

    2013-09-01

    We review critical trends in imaging genetics as applied to schizophrenia research, and then discuss some future directions of the field. A plethora of imaging genetics studies have investigated the impact of genetic variation on brain function, since the paradigm of a neuroimaging intermediate phenotype for schizophrenia first emerged. It was initially posited that the effects of schizophrenia susceptibility genes would be more penetrant at the level of biologically based neuroimaging intermediate phenotypes than at the level of a complex and phenotypically heterogeneous psychiatric syndrome. The results of many studies support this assumption, most of which show single genetic variants to be associated with changes in activity of localized brain regions, as determined by select cognitive controlled tasks. From these basic studies, functional neuroimaging analysis of intermediate phenotypes has progressed to more complex and realistic models of brain dysfunction, incorporating models of functional and effective connectivity, including the modalities of psycho-physiological interaction, dynamic causal modeling, and graph theory metrics. The genetic association approaches applied to imaging genetics have also progressed to more sophisticated multivariate effects, including incorporation of two-way and three-way epistatic interactions, and most recently polygenic risk models. Imaging genetics is a unique and powerful strategy for understanding the neural mechanisms of genetic risk for complex CNS disorders at the human brain level.

  11. Brain structure and function related to depression in Alzheimer's disease: contributions from neuroimaging research.

    PubMed

    Brommelhoff, Jessica A; Sultzer, David L

    2015-01-01

    The development of minimally invasive in vivo methods for imaging the brain has allowed for unprecedented advancement in our understanding of brain-behavior relationships. Structural, functional, and multimodal neuroimaging techniques have become more sophisticated in detecting structural and physiological abnormalities that may underlie various affective disorders and neurological illnesses such as depression in Alzheimer's disease (AD). In general, neuroimaging studies of depression in AD investigate whether depression is associated with damage to structures in specific neural networks involving frontal and subcortical structures or with functional disruption of cortical neural systems. This review provides an overview of how various imaging modalities have contributed to our understanding of the neurobiology of depression in AD. At present, the literature does not conclusively support any specific pathogenesis for depression, and it is not clear whether patients with AD and depression have histopathological and neurochemical characteristics that contribute to mood symptoms that are different from cognitively intact individuals with depression. Neuroimaging studies suggest that atrophy of temporal or frontal structures, white matter lesions in frontal lobe or subcortical systems, reduced activity in dorsolateral frontal cortex, or small vessel cerebrovascular disease may be associated with depression in AD. Conceptual, clinical, and methodological challenges in studying this relationship are discussed. Further work is needed to understand the specific brain structures, relevant white matter tracts, and interactions among them that are most important. This review concludes with potential directions for future research.

  12. Pattern classification of large-scale functional brain networks: identification of informative neuroimaging markers for epilepsy.

    PubMed

    Zhang, Jie; Cheng, Wei; Wang, ZhengGe; Zhang, ZhiQiang; Lu, WenLian; Lu, GuangMing; Feng, Jianfeng

    2012-01-01

    The accurate prediction of general neuropsychiatric disorders, on an individual basis, using resting-state functional magnetic resonance imaging (fMRI) is a challenging task of great clinical significance. Despite the progress to chart the differences between the healthy controls and patients at the group level, the pattern classification of functional brain networks across individuals is still less developed. In this paper we identify two novel neuroimaging measures that prove to be strongly predictive neuroimaging markers in pattern classification between healthy controls and general epileptic patients. These measures characterize two important aspects of the functional brain network in a quantitative manner: (i) coordinated operation among spatially distributed brain regions, and (ii) the asymmetry of bilaterally homologous brain regions, in terms of their global patterns of functional connectivity. This second measure offers a unique understanding of brain asymmetry at the network level, and, to the best of our knowledge, has not been previously used in pattern classification of functional brain networks. Using modern pattern-recognition approaches like sparse regression and support vector machine, we have achieved a cross-validated classification accuracy of 83.9% (specificity: 82.5%; sensitivity: 85%) across individuals from a large dataset consisting of 180 healthy controls and epileptic patients. We identified significantly changed functional pathways and subnetworks in epileptic patients that underlie the pathophysiological mechanism of the impaired cognitive functions. Specifically, we find that the asymmetry of brain operation for epileptic patients is markedly enhanced in temporal lobe and limbic system, in comparison with healthy individuals. The present study indicates that with specifically designed informative neuroimaging markers, resting-state fMRI can serve as a most promising tool for clinical diagnosis, and also shed light onto the physiology

  13. Functional neuroanatomy of meditation: A review and meta-analysis of 78 functional neuroimaging investigations.

    PubMed

    Fox, Kieran C R; Dixon, Matthew L; Nijeboer, Savannah; Girn, Manesh; Floman, James L; Lifshitz, Michael; Ellamil, Melissa; Sedlmeier, Peter; Christoff, Kalina

    2016-06-01

    Meditation is a family of mental practices that encompasses a wide array of techniques employing distinctive mental strategies. We systematically reviewed 78 functional neuroimaging (fMRI and PET) studies of meditation, and used activation likelihood estimation to meta-analyze 257 peak foci from 31 experiments involving 527 participants. We found reliably dissociable patterns of brain activation and deactivation for four common styles of meditation (focused attention, mantra recitation, open monitoring, and compassion/loving-kindness), and suggestive differences for three others (visualization, sense-withdrawal, and non-dual awareness practices). Overall, dissociable activation patterns are congruent with the psychological and behavioral aims of each practice. Some brain areas are recruited consistently across multiple techniques-including insula, pre/supplementary motor cortices, dorsal anterior cingulate cortex, and frontopolar cortex-but convergence is the exception rather than the rule. A preliminary effect-size meta-analysis found medium effects for both activations (d=0.59) and deactivations (d=-0.74), suggesting potential practical significance. Our meta-analysis supports the neurophysiological dissociability of meditation practices, but also raises many methodological concerns and suggests avenues for future research.

  14. Contribution of Neuroimaging Studies to Understanding Development of Human Cognitive Brain Functions.

    PubMed

    Morita, Tomoyo; Asada, Minoru; Naito, Eiichi

    2016-01-01

    Humans experience significant physical and mental changes from birth to adulthood, and a variety of perceptual, cognitive and motor functions mature over the course of approximately 20 years following birth. To deeply understand such developmental processes, merely studying behavioral changes is not sufficient; simultaneous investigation of the development of the brain may lead us to a more comprehensive understanding. Recent advances in noninvasive neuroimaging technologies largely contribute to this understanding. Here, it is very important to consider the development of the brain from the perspectives of "structure" and "function" because both structure and function of the human brain mature slowly. In this review, we first discuss the process of structural brain development, i.e., how the structure of the brain, which is crucial when discussing functional brain development, changes with age. Second, we introduce some representative studies and the latest studies related to the functional development of the brain, particularly for visual, facial recognition, and social cognition functions, all of which are important for humans. Finally, we summarize how brain science can contribute to developmental study and discuss the challenges that neuroimaging should address in the future.

  15. Contribution of Neuroimaging Studies to Understanding Development of Human Cognitive Brain Functions

    PubMed Central

    Morita, Tomoyo; Asada, Minoru; Naito, Eiichi

    2016-01-01

    Humans experience significant physical and mental changes from birth to adulthood, and a variety of perceptual, cognitive and motor functions mature over the course of approximately 20 years following birth. To deeply understand such developmental processes, merely studying behavioral changes is not sufficient; simultaneous investigation of the development of the brain may lead us to a more comprehensive understanding. Recent advances in noninvasive neuroimaging technologies largely contribute to this understanding. Here, it is very important to consider the development of the brain from the perspectives of “structure” and “function” because both structure and function of the human brain mature slowly. In this review, we first discuss the process of structural brain development, i.e., how the structure of the brain, which is crucial when discussing functional brain development, changes with age. Second, we introduce some representative studies and the latest studies related to the functional development of the brain, particularly for visual, facial recognition, and social cognition functions, all of which are important for humans. Finally, we summarize how brain science can contribute to developmental study and discuss the challenges that neuroimaging should address in the future. PMID:27695409

  16. The micro-architecture of the cerebral cortex: Functional neuroimaging models and metabolism

    PubMed Central

    Riera, Jorge J.; Schousboe, Arne; Waagepetersen, Helle S.; Howarth, Clare; Hyder, Fahmeed

    2014-01-01

    In order to interpret/integrate data obtained with different functional neuroimaging modalities (e.g. fMRI, EEG/MEG, PET/SPECT, fNIRS), forward-generative models of a diversity of brain mechanisms at the mesoscopic level are considered necessary. For the cerebral cortex, the brain structure with possibly the most relevance for functional neuroimaging, a variety of such biophysical models has been proposed over the last decade. The development of technological tools to investigate in vitro the physiological, anatomical and biochemical principles at the microscopic scale in comparative studies formed the basis for such theoretical progresses. However, with the most recent introduction of systems to record electrical (e.g. miniaturized probes chronically/acutely implantable in the brain), optical (e.g. two-photon laser scanning microscopy) and atomic nuclear spectral (e.g. nuclear magnetic resonance spectroscopy) signals using living laboratory animals, the field is receiving even greater attention. Major advances have been achieved by combining such sophisticated recording systems with new experimental strategies (e.g. transgenic/knock-out animals, high resolution stereotaxic manipulation systems for probe-guidance and cellular-scale chemical-delivery). Theoreticians may now be encouraged to re-consider previously formulated mesoscopic level models in order to incorporate important findings recently made at the microscopic scale. In this series of reviews, we summarize the background at the microscopic scale, which we suggest will constitute the foundations for upcoming representations at the mesoscopic level. In this first part, we focus our attention on the nerve ending particles in order to summarize basic principles and mechanisms underlying cellular metabolism in the cerebral cortex. It will be followed by two parts highlighting major features in its organization/working-principles to regulate both cerebral blood circulation and neuronal activity, respectively

  17. Using neural modeling and functional neuroimaging to study the neural basis of auditory object processing

    NASA Astrophysics Data System (ADS)

    Horwitz, Barry; Husain, Fatima T.

    2003-04-01

    The neural basis of auditory object processing in the human cerebral cortex was investigated by combining neural modeling and functional neuroimaging. We developed a large-scale, neurobiologically realistic network model of auditory pattern recognition that relates neuronal dynamics of cortical auditory processing of frequency-modulated (FM) sweeps to functional neuroimaging data obtained using functional magnetic resonance imaging (fMRI). FM sweeps are ubiquitous in animal communication. Areas included in the model extend from primary auditory to prefrontal cortex. The electrical activities of the model neuronal units were constrained to agree with data from the neurophysiological literature regarding FM sweep perception. A fMRI experiment using stimuli and tasks similar to those used in our simulations was performed. The regional integrated synaptic activities of the model were used to determine simulated regional fMRI activities, and generally agreed with the experimentally observed fMRI data. Our results demonstrate that the model is capable of exhibiting the salient features of both electrophysiological neuronal activities and fMRI values that are in agreement with empirically observed data. These findings provide support for our hypotheses concerning how auditory objects are processed by primate neocortex. This type of approach offers the potential for understanding the neural basis of human speech perception.

  18. Amino acid challenge and depletion techniques in human functional neuroimaging studies: an overview.

    PubMed

    Biskup, C S; Gaber, T; Helmbold, K; Bubenzer-Busch, S; Zepf, F D

    2015-04-01

    Imbalances of neurotransmitter systems, particularly serotonin (5-HT) and dopamine (DA), are known to play an essential role in many neuropsychiatric disorders. The transient manipulation of such systems through the alteration of their amino acid precursors is a well-known research tool. Among these methods are alterations of tryptophan, the essential amino acid (AA) precursor of 5-HT, as well as manipulations of tyrosine and phenylalanine, the AA precursors of DA, which can be metabolized into norepinephrine and subsequently into epinephrine. These systems can be loaded by applying a large dose of these AAs or depleted by applying an amino acid mixture lacking the respective AAs serving as precursors. Functional neuroimaging has given insights into differential brain activation patterns and functions depending on the tasks performed, pharmacological treatments or specific disorders. Such research has shed light on the function of many brain areas as well as their interactions. The combination of AA challenge approaches with neuroimaging techniques has been subject of numerous studies. Overall, the studies conducted in this particular field of research have shown that AA challenge techniques are valid and effective research tools that allow the investigation of serotonergic and dopaminergic systems without causing serious side effects or long-term damage to the subjects. In this review, we will present an overview of the results obtained so far and discuss the implications of these findings as well as open questions that remain to be answered.

  19. Haptic fMRI: combining functional neuroimaging with haptics for studying the brain's motor control representation.

    PubMed

    Menon, Samir; Brantner, Gerald; Aholt, Chris; Kay, Kendrick; Khatib, Oussama

    2013-01-01

    A challenging problem in motor control neuroimaging studies is the inability to perform complex human motor tasks given the Magnetic Resonance Imaging (MRI) scanner's disruptive magnetic fields and confined workspace. In this paper, we propose a novel experimental platform that combines Functional MRI (fMRI) neuroimaging, haptic virtual simulation environments, and an fMRI-compatible haptic device for real-time haptic interaction across the scanner workspace (above torso ∼ .65×.40×.20m(3)). We implement this Haptic fMRI platform with a novel haptic device, the Haptic fMRI Interface (HFI), and demonstrate its suitability for motor neuroimaging studies. HFI has three degrees-of-freedom (DOF), uses electromagnetic motors to enable high-fidelity haptic rendering (>350Hz), integrates radio frequency (RF) shields to prevent electromagnetic interference with fMRI (temporal SNR >100), and is kinematically designed to minimize currents induced by the MRI scanner's magnetic field during motor displacement (<2cm). HFI possesses uniform inertial and force transmission properties across the workspace, and has low friction (.05-.30N). HFI's RF noise levels, in addition, are within a 3 Tesla fMRI scanner's baseline noise variation (∼.85±.1%). Finally, HFI is haptically transparent and does not interfere with human motor tasks (tested for .4m reaches). By allowing fMRI experiments involving complex three-dimensional manipulation with haptic interaction, Haptic fMRI enables-for the first time-non-invasive neuroscience experiments involving interactive motor tasks, object manipulation, tactile perception, and visuo-motor integration.

  20. The Role of Functional Neuroimaging in Pre-Surgical Epilepsy Evaluation

    PubMed Central

    Pittau, Francesca; Grouiller, Frédéric; Spinelli, Laurent; Seeck, Margitta; Michel, Christoph M.; Vulliemoz, Serge

    2014-01-01

    The prevalence of epilepsy is about 1% and one-third of cases do not respond to medical treatment. In an eligible subset of patients with drug-resistant epilepsy, surgical resection of the epileptogenic zone is the only treatment that can possibly cure the disease. Non-invasive techniques provide information for the localization of the epileptic focus in the majority of cases, whereas in others invasive procedures are required. In the last years, non-invasive neuroimaging techniques, such as simultaneous recording of functional magnetic resonance imaging and electroencephalogram (EEG-fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), electric and magnetic source imaging (MSI, ESI), spectroscopy (MRS), have proved their usefulness in defining the epileptic focus. The combination of these functional techniques can yield complementary information and their concordance is crucial for guiding clinical decision, namely the planning of invasive EEG recordings or respective surgery. The aim of this review is to present these non-invasive neuroimaging techniques, their potential combination, and their role in the pre-surgical evaluation of patients with pharmaco-resistant epilepsy. PMID:24715886

  1. Advanced magnetic resonance neuroimaging of language function recovery after aphasic stroke: a technical review.

    PubMed

    Smits, Marion; Visch-Brink, Evy G; van de Sandt-Koenderman, Mieke E; van der Lugt, Aad

    2012-01-01

    Two advanced magnetic resonance neuroimaging techniques, functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), have recently made their way into clinically oriented research and hold great promise to study the brain's adaptive changes of function and structure after aphasic stroke, respectively. Such functional and structural neuroplasticity is thought to underlie the recovery of language function, occurring spontaneously and/or in the context of therapeutic intervention. With fMRI, brain activity can be visualized. Spontaneous brain activity, present in multiple brain networks, is measured with resting-state fMRI and language-related brain activity by having the subject perform a language task during scanning (task-based fMRI). With DTI the major white matter tracts, such as the dorsal and ventral language pathways and the commissural fibers, can be visualized and quantified. Both techniques are entirely noninvasive and thus offer the unique opportunity to perform multiple assessments within the same subject. To gain more insight in functional and structural neuroplasticity after aphasic stroke, advanced magnetic resonance neuroimaging studies in specific patient populations, at several stages after stroke and in the course of language recovery, are needed. Such studies will help to clarify the influence of the many factors that play a role in the recovery of language function and are thus vital to further the development of aphasia therapy. Application of these techniques in aphasic stroke patients, however, is not without challenge. The purpose of this article is to discuss the methodologic challenges of fMRI and DTI in the assessment of language recovery after aphasic stroke.

  2. The social evaluation of faces: a meta-analysis of functional neuroimaging studies

    PubMed Central

    Mende-Siedlecki, Peter; Said, Christopher P.

    2013-01-01

    Neuroscience research on the social evaluation of faces has accumulated over the last decade, yielding divergent results. We used a meta-analytic technique, multi-level kernel density analysis (MKDA), to analyze 29 neuroimaging studies on face evaluation. Across negative face evaluations, we observed the most consistent activations in bilateral amygdala. Across positive face evaluations, we observed the most consistent activations in medial prefrontal cortex, pregenual anterior cingulate cortex (pgACC), medial orbitofrontal cortex (mOFC), left caudate and nucleus accumbens (NAcc). Based on additional analyses comparing linear and non-linear responses, we propose a ventral/dorsal dissociation within the amygdala, wherein separate populations of neurons code for face valence and intensity, respectively. Finally, we argue that some of the differences between studies are attributable to differences in the typicality of face stimuli. Specifically, extremely attractive faces are more likely to elicit responses in NAcc/caudate and mOFC. PMID:22287188

  3. Multilevel Dynamic Generalized Structured Component Analysis for Brain Connectivity Analysis in Functional Neuroimaging Data.

    PubMed

    Jung, Kwanghee; Takane, Yoshio; Hwang, Heungsun; Woodward, Todd S

    2016-06-01

    We extend dynamic generalized structured component analysis (GSCA) to enhance its data-analytic capability in structural equation modeling of multi-subject time series data. Time series data of multiple subjects are typically hierarchically structured, where time points are nested within subjects who are in turn nested within a group. The proposed approach, named multilevel dynamic GSCA, accommodates the nested structure in time series data. Explicitly taking the nested structure into account, the proposed method allows investigating subject-wise variability of the loadings and path coefficients by looking at the variance estimates of the corresponding random effects, as well as fixed loadings between observed and latent variables and fixed path coefficients between latent variables. We demonstrate the effectiveness of the proposed approach by applying the method to the multi-subject functional neuroimaging data for brain connectivity analysis, where time series data-level measurements are nested within subjects.

  4. Are numbers grounded in a general magnitude processing system? A functional neuroimaging meta-analysis.

    PubMed

    Sokolowski, H Moriah; Fias, Wim; Bosah Ononye, Chuka; Ansari, Daniel

    2017-01-22

    It is currently debated whether numbers are processed using a number-specific system or a general magnitude processing system, also used for non-numerical magnitudes such as physical size, duration, or luminance. Activation likelihood estimation (ALE) was used to conduct the first quantitative meta-analysis of 93 empirical neuroimaging papers examining neural activation during numerical and non-numerical magnitude processing. Foci were compiled to generate probabilistic maps of activation for non-numerical magnitudes (e.g. physical size), symbolic numerical magnitudes (e.g. Arabic digits), and nonsymbolic numerical magnitudes (e.g. dot arrays). Conjunction analyses revealed overlapping activation for symbolic, nonsymbolic and non-numerical magnitudes in frontal and parietal lobes. Contrast analyses revealed specific activation in the left superior parietal lobule for symbolic numerical magnitudes. In contrast, small regions in the bilateral precuneus were specifically activated for nonsymbolic numerical magnitudes. No regions in the parietal lobes were activated for non-numerical magnitudes that were not also activated for numerical magnitudes. Therefore, numbers are processed using both a generalized magnitude system and format specific number regions.

  5. A SPARSE REDUCED RANK FRAMEWORK FOR GROUP ANALYSIS OF FUNCTIONAL NEUROIMAGING DATA.

    PubMed

    Ahn, Mihye; Shen, Haipeng; Lin, Weili; Zhu, Hongtu

    2015-01-01

    In spatial-temporal neuroimaging studies, there is an evolving literature on the analysis of functional imaging data in order to learn the intrinsic functional connectivity patterns among different brain regions. However, there are only few efficient approaches for integrating functional connectivity pattern across subjects, while accounting for spatial-temporal functional variation across multiple groups of subjects. The objective of this paper is to develop a new sparse reduced rank (SRR) modeling framework for carrying out functional connectivity analysis across multiple groups of subjects in the frequency domain. Our new framework not only can extract both frequency and spatial factors across subjects, but also imposes sparse constraints on the frequency factors. It thus leads to the identification of important frequencies with high power spectra. In addition, we propose two novel adaptive criteria for automatic selection of sparsity level and model rank. Using simulated data, we demonstrate that SRR outperforms several existing methods. Finally, we apply SRR to detect group differences between controls and two subtypes of attention deficit hyperactivity disorder (ADHD) patients, through analyzing the ADHD-200 data.

  6. Evidence against functionalism from neuroimaging of the alien colour effect in synaesthesia.

    PubMed

    Gray, Jeffrey A; Parslow, David M; Brammer, Michael J; Chopping, Susan; Vythelingum, Goparlen N; ffytche, Dominic H

    2006-02-01

    Coloured hearing synaesthetes experience colours to heard words, as confirmed by reliability of self-report, psychophysical testing and functional neuroimaging data. Some also describe the 'alien colour effect' (ACE): in response to colour names, they experience colours different from those named. We have previously reported that the ACE slows colour naming in a Stroop task, reflecting cognitive interference from synaesthetically induced colours, which depends upon their being consciously experienced. It has been proposed that the hippocampus mediates such consciously experienced conflict. Consistent with this hypothesis, we now report that, in functional magnetic resonance imaging of the Stroop task, hippocampal activation differentiates synaesthetes with the ACE from those without it and from non-synaesthete controls. These findings confirm the reality of coloured hearing synaesthesia and the ACE, phenomena which pose major challenges to the dominant contemporary account of mental states, functionalism. Reductive functionalism identifies types of mental states with causal roles: relations to inputs, outputs and other states. However, conscious mental states, such as experiences of colour, are distinguished by their qualitative properties or qualia. If functionalism is applied to conscious mental states, it identifies the qualitative type of an experience with its causal role or function. This entails both that experiences with disparate qualitative properties cannot have the same functional properties, and that experiences with disparate functional properties cannot have the same qualitative properties. Challenges to functionalism have often denied the first entailment. Here, we challenge the second entailment on empirical grounds. In coloured hearing synaesthesia, colour qualia are associated with both hearing words and seeing surfaces; and, in the ACE, these two functions act in opposition to one another. Whatever its merits as an account of other mental states

  7. Functional neuro-imaging as a pre-surgical tool in epilepsy.

    PubMed

    Haneef, Zulfi; Chen, David K

    2014-03-01

    Functional neuro-imaging techniques are helpful in the pre-surgical evaluation of epilepsy for localization of the epileptogenic zone as ancillary tools to electroencephalography (EEG) and magnetic resonance imaging (MRI) or when other localization techniques are normal, non-concordant or discordant. Positron emission tomography (PET) and ictal single photon emission computed tomography (ictal SPECT) imaging are traditional tests that have been reported to have good sensitivity and specificity although the results are better with more expertise as is true for any technique. More recently magnetoencephalogram/magnetic source imaging (MEG/MSI), diffusion tensor imaging and functional magnetic resonance imaging (fMRI) have been used in localization and functional mapping during the pre-surgical work-up of epilepsy. Newer techniques such as fMRI-EEG, functional connectivity magnetic resonance imaging and near infra-red spectroscopy, magnetic resonance spectroscopy and magneto nanoparticles hold promise for further development that could then be applied in the work-up of epilepsy surgery. In this manuscript, we review these techniques and their current position in the pre-surgical evaluation of epilepsy.

  8. Functional neuro-imaging as a pre-surgical tool in epilepsy

    PubMed Central

    Haneef, Zulfi; Chen, David K.

    2014-01-01

    Functional neuro-imaging techniques are helpful in the pre-surgical evaluation of epilepsy for localization of the epileptogenic zone as ancillary tools to electroencephalography (EEG) and magnetic resonance imaging (MRI) or when other localization techniques are normal, non-concordant or discordant. Positron emission tomography (PET) and ictal single photon emission computed tomography (ictal SPECT) imaging are traditional tests that have been reported to have good sensitivity and specificity although the results are better with more expertise as is true for any technique. More recently magnetoencephalogram/magnetic source imaging (MEG/MSI), diffusion tensor imaging and functional magnetic resonance imaging (fMRI) have been used in localization and functional mapping during the pre-surgical work-up of epilepsy. Newer techniques such as fMRI-EEG, functional connectivity magnetic resonance imaging and near infra-red spectroscopy, magnetic resonance spectroscopy and magneto nanoparticles hold promise for further development that could then be applied in the work-up of epilepsy surgery. In this manuscript, we review these techniques and their current position in the pre-surgical evaluation of epilepsy. PMID:24791091

  9. A functional neuroimaging study of the variables that generate category-specific object processing differences.

    PubMed

    Moore, C J; Price, C J

    1999-05-01

    Brain damage can cause remarkably selective deficits in processing specific categories of objects, indicating the high degree of functional segregation within the brain. The neuroimaging study presented here investigates differences in the neural activity associated with two categories of natural objects (animals and fruit) and two categories of man-made objects (vehicles and tools). Stimuli were outline drawings and the tasks were naming and word-picture matching. For man-made objects, the only category-specific effect was in the left posterior middle temporal cortex, which was most active for drawings of tools, as previously reported. For natural objects, drawings of animals and fruit (relative to drawings of man-made objects) enhanced activity in bilateral anterior temporal and right posterior middle temporal cortices. Critically, these effects with natural objects were not observed when the stimuli were coloured appropriately to facilitate identification. Furthermore, activation in the same right hemisphere areas was also observed for viewing and matching unfamiliar non-objects relative to naming and matching man-made objects. These results indicate that, in the right hemisphere, differences between processing natural relative to man-made objects overlap with the effects of increasing demands on object identification. In the left hemisphere, the effects are more consistent with functional specialization within the semantic system. We discuss (i) how category-specific differences can emerge for multiple reasons and (ii) the implications of these effects on the interpretation of functional imaging data and patients with category-specific deficits.

  10. Hyperarousal and Beyond: New Insights to the Pathophysiology of Insomnia Disorder through Functional Neuroimaging Studies

    PubMed Central

    Kay, Daniel B.; Buysse, Daniel J.

    2017-01-01

    Neuroimaging studies have produced seemingly contradictory findings in regards to the pathophysiology of insomnia. Although most study results are interpreted from the perspective of a “hyperarousal” model, the aggregate findings from neuroimaging studies suggest a more complex model is needed. We provide a review of the major findings from neuroimaging studies, then discuss them in relation to a heuristic model of sleep-wake states that involves three major factors: wake drive, sleep drive, and level of conscious awareness. We propose that insomnia involves dysregulation in these factors, resulting in subtle dysregulation of sleep-wake states throughout the 24 h light/dark cycle. PMID:28241468

  11. Functional neuroimaging of amphetamine-induced striatal neurotoxicity in the pleiotrophin knockout mouse model.

    PubMed

    Soto-Montenegro, María Luisa; Vicente-Rodríguez, Marta; Pérez-García, Carmen; Gramage, Esther; Desco, Manuel; Herradón, Gonzalo

    2015-03-30

    Amphetamine-induced neurotoxic effects have traditionally been studied using immunohistochemistry and other post-mortem techniques, which have proven invaluable for the definition of amphetamine-induced dopaminergic damage in the nigrostriatal pathway. However, these approaches are limited in that they require large numbers of animals and do not provide the temporal data that can be collected in longitudinal studies using functional neuroimaging techniques. Unfortunately, functional imaging studies in rodent models of drug-induced neurotoxicity are lacking. The aim of this study was to evaluate in vivo the changes in brain glucose metabolism caused by amphetamine in the pleiotrophin knockout mouse (PTN-/-), a genetic model with increased vulnerability to amphetamine-induced neurotoxic effects. We showed that administration of amphetamine causes a significantly greater loss of striatal tyrosine hydroxylase content in PTN-/- mice than in wild-type (WT) mice. In addition, [(18)F]-FDG-PET shows that amphetamine produces a significant decrease in glucose metabolism in the striatum and prefrontal cortex in the PTN-/- mice, compared to WT mice. These findings suggest that [(18)F]-FDG uptake measured by PET is useful for detecting amphetamine-induced changes in glucose metabolism in vivo in specific brain areas, including the striatum, a key feature of amphetamine-induced neurotoxicity.

  12. Where Is the Semantic System? A Critical Review and Meta-Analysis of 120 Functional Neuroimaging Studies

    PubMed Central

    Desai, Rutvik H.; Graves, William W.; Conant, Lisa L.

    2009-01-01

    Semantic memory refers to knowledge about people, objects, actions, relations, self, and culture acquired through experience. The neural systems that store and retrieve this information have been studied for many years, but a consensus regarding their identity has not been reached. Using strict inclusion criteria, we analyzed 120 functional neuroimaging studies focusing on semantic processing. Reliable areas of activation in these studies were identified using the activation likelihood estimate (ALE) technique. These activations formed a distinct, left-lateralized network comprised of 7 regions: posterior inferior parietal lobe, middle temporal gyrus, fusiform and parahippocampal gyri, dorsomedial prefrontal cortex, inferior frontal gyrus, ventromedial prefrontal cortex, and posterior cingulate gyrus. Secondary analyses showed specific subregions of this network associated with knowledge of actions, manipulable artifacts, abstract concepts, and concrete concepts. The cortical regions involved in semantic processing can be grouped into 3 broad categories: posterior multimodal and heteromodal association cortex, heteromodal prefrontal cortex, and medial limbic regions. The expansion of these regions in the human relative to the nonhuman primate brain may explain uniquely human capacities to use language productively, plan, solve problems, and create cultural and technological artifacts, all of which depend on the fluid and efficient retrieval and manipulation of semantic knowledge. PMID:19329570

  13. Comparison of the disparity between Talairach and MNI coordinates in functional neuroimaging data: Validation of the Lancaster transform

    PubMed Central

    Laird, Angela R.; Robinson, Jennifer L.; McMillan, Kathryn M.; Tordesillas-Gutiérrez, Diana; Moran, Sarah T.; Gonzales, Sabina M.; Ray, Kimberly L.; Franklin, Crystal; Glahn, David C.; Fox, Peter T.; Lancaster, Jack L.

    2010-01-01

    Spatial normalization of neuroimaging data is a standard step when assessing group effects. As a result of divergent analysis procedures due to different normalization algorithms or templates, not all published coordinates refer to the same neuroanatomical region. Specifically, the literature is populated with results in the form of MNI or Talairach coordinates, and their disparity can impede the comparison of results across different studies. This becomes particularly problematic in coordinate-based meta-analyses, wherein coordinate disparity should be corrected to reduce error and facilitate literature reviews. In this study, a quantitative comparison was performed on two corrections, the Brett transform (i.e., “mni2tal”), and the Lancaster transform (i.e., “icbm2tal”). Functional magnetic resonance imaging (fMRI) data acquired during a standard paired associates task indicated that the disparity between MNI and Talairach coordinates was better reduced via the Lancaster transform, as compared to the Brett transform. In addition, an activation likelihood estimation (ALE) meta-analysis of the paired associates literature revealed that a higher degree of concordance was obtained when using the Lancaster transform in the form of fewer, smaller, and more intense clusters. Based on these results, we recommend that the Lancaster transform be adopted as the community standard for reducing disparity between results reported as MNI or Talairach coordinates, and suggest that future spatial normalization strategies be designed to minimize this variability in the literature. PMID:20197097

  14. The neural basis of semantic and episodic forms of self-knowledge: insights from functional neuroimaging.

    PubMed

    D'Argembeau, Arnaud; Salmon, Eric

    2012-01-01

    Throughout evolution, hominids have developed greater capacity to think about themselves in abstract and symbolic ways. This process has reached its apex in humans with the construction of a concept of self as a distinct entity with a personal history. This chapter provides a review of recent functional neuroimaging studies that have investigated the neural correlates of such "higher-level" aspects of the human self, focusing in particular on processes that allow individuals to consciously represent and reflect on their own personal attributes (semantic forms of self-knowledge) and experiences (episodic forms of self-knowledge). These studies point to the medial prefrontal cortex (MPFC) as a key neural structure for processing various kinds of self-referential information. We speculate that the MPFC may mediate dynamic processes that appraise and code the self-relatedness or self-relevance of information. This brain region may thus play a key role in creating the mental model of the self that is displayed in our mind at a given moment.

  15. Dissociation between emotion and personality judgments: convergent evidence from functional neuroimaging.

    PubMed

    Heberlein, Andrea S; Saxe, Rebecca R

    2005-12-01

    Cognitive neuroscientists widely agree on the importance of providing convergent evidence from neuroimaging and lesion studies to establish structure-function relationships. However, such convergent evidence is, in practice, rarely provided. A previous lesion study found a striking double dissociation between two superficially similar social judgment processes, emotion recognition and personality attribution, based on the same body movement stimuli (point-light walkers). Damage to left frontal opercular (LFO) cortices was associated with impairments in personality trait attribution, whereas damage to right postcentral/supramarginal cortices was associated with impairments in emotional state attribution. Here, we present convergent evidence from fMRI in support of this double dissociation, with regions of interest (ROIs) defined by the regions of maximal lesion overlap from the previous study. Subjects learned four emotion words and four trait words, then watched a series of short point-light walker body movement stimuli. After each stimulus, subjects saw either an emotion word or a trait word and rated how well the word described the stimulus. The LFO ROI exhibited greater activity during personality judgments than during emotion judgments. In contrast, the right postcentral/supramarginal ROI exhibited greater activity during emotion judgments than during personality judgments. Follow-up experiments ruled out the possibility that the LFO activation difference was due to word frequency differences. Additionally, we found greater activity in a region of the medial prefrontal cortex previously associated with "theory of mind" tasks when subjects made personality, as compared to emotion judgments.

  16. Computational principles of syntax in the regions specialized for language: integrating theoretical linguistics and functional neuroimaging

    PubMed Central

    Ohta, Shinri; Fukui, Naoki; Sakai, Kuniyoshi L.

    2013-01-01

    The nature of computational principles of syntax remains to be elucidated. One promising approach to this problem would be to construct formal and abstract linguistic models that parametrically predict the activation modulations in the regions specialized for linguistic processes. In this article, we review recent advances in theoretical linguistics and functional neuroimaging in the following respects. First, we introduce the two fundamental linguistic operations: Merge (which combines two words or phrases to form a larger structure) and Search (which searches and establishes a syntactic relation of two words or phrases). We also illustrate certain universal properties of human language, and present hypotheses regarding how sentence structures are processed in the brain. Hypothesis I is that the Degree of Merger (DoM), i.e., the maximum depth of merged subtrees within a given domain, is a key computational concept to properly measure the complexity of tree structures. Hypothesis II is that the basic frame of the syntactic structure of a given linguistic expression is determined essentially by functional elements, which trigger Merge and Search. We then present our recent functional magnetic resonance imaging experiment, demonstrating that the DoM is indeed a key syntactic factor that accounts for syntax-selective activations in the left inferior frontal gyrus and supramarginal gyrus. Hypothesis III is that the DoM domain changes dynamically in accordance with iterative Merge applications, the Search distances, and/or task requirements. We confirm that the DoM accounts for activations in various sentence types. Hypothesis III successfully explains activation differences between object- and subject-relative clauses, as well as activations during explicit syntactic judgment tasks. A future research on the computational principles of syntax will further deepen our understanding of uniquely human mental faculties. PMID:24385957

  17. Computational principles of syntax in the regions specialized for language: integrating theoretical linguistics and functional neuroimaging.

    PubMed

    Ohta, Shinri; Fukui, Naoki; Sakai, Kuniyoshi L

    2013-01-01

    The nature of computational principles of syntax remains to be elucidated. One promising approach to this problem would be to construct formal and abstract linguistic models that parametrically predict the activation modulations in the regions specialized for linguistic processes. In this article, we review recent advances in theoretical linguistics and functional neuroimaging in the following respects. First, we introduce the two fundamental linguistic operations: Merge (which combines two words or phrases to form a larger structure) and Search (which searches and establishes a syntactic relation of two words or phrases). We also illustrate certain universal properties of human language, and present hypotheses regarding how sentence structures are processed in the brain. Hypothesis I is that the Degree of Merger (DoM), i.e., the maximum depth of merged subtrees within a given domain, is a key computational concept to properly measure the complexity of tree structures. Hypothesis II is that the basic frame of the syntactic structure of a given linguistic expression is determined essentially by functional elements, which trigger Merge and Search. We then present our recent functional magnetic resonance imaging experiment, demonstrating that the DoM is indeed a key syntactic factor that accounts for syntax-selective activations in the left inferior frontal gyrus and supramarginal gyrus. Hypothesis III is that the DoM domain changes dynamically in accordance with iterative Merge applications, the Search distances, and/or task requirements. We confirm that the DoM accounts for activations in various sentence types. Hypothesis III successfully explains activation differences between object- and subject-relative clauses, as well as activations during explicit syntactic judgment tasks. A future research on the computational principles of syntax will further deepen our understanding of uniquely human mental faculties.

  18. A clinical case study of a psychoanalytic psychotherapy monitored with functional neuroimaging

    PubMed Central

    Buchheim, Anna; Labek, Karin; Walter, Steffen; Viviani, Roberto

    2013-01-01

    This case study describes 1 year of the psychoanalytic psychotherapy using clinical data, a standardized instrument of the psychotherapeutic process (Psychotherapy process Q-Set, PQS), and functional neuroimaging (fMRI). A female dysthymic patient with narcissistic traits was assessed at monthly intervals (12 sessions). In the fMRI scans, which took place immediately after therapy hours, the patient looked at pictures of attachment-relevant scenes (from the Adult Attachment Projective Picture System, AAP) divided into two groups: those accompanied by a neutral description, and those accompanied by a description tailored to core conflicts of the patient as assessed in the AAP. Clinically, this patient presented defense mechanisms that influenced the relationship with the therapist and that was characterized by fluctuations of mood that lasted whole days, following a pattern that remained stable during the year of the study. The two modes of functioning associated with the mood shifts strongly affected the interaction with the therapist, whose quality varied accordingly (“easy” and “difficult” hours). The PQS analysis showed the association of “easy” hours with the topic of the involvement in significant relationships and of “difficult hours” with self-distancing, a defensive maneuver common in narcissistic personality structures. In the fMRI data, the modes of functioning visible in the therapy hours were significantly associated with modulation of the signal elicited by personalized attachment-related scenes in the posterior cingulate (p = 0.017 cluster-level, whole-volume corrected). This region has been associated in previous studies to self-distancing from negatively valenced pictures presented during the scan. The present study may provide evidence of the possible involvement of this brain area in spontaneously enacted self-distancing defensive strategies, which may be of relevance in resistant reactions in the course of a psychoanalytic

  19. Brain basis of early parent–infant interactions: psychology, physiology, and in vivo functional neuroimaging studies

    PubMed Central

    Swain, James E.; Lorberbaum, Jeffrey P.; Kose, Samet; Strathearn, Lane

    2015-01-01

    Parenting behavior critically shapes human infants’ current and future behavior. The parent–infant relationship provides infants with their first social experiences, forming templates of what they can expect from others and how to best meet others’ expectations. In this review, we focus on the neurobiology of parenting behavior, including our own functional magnetic resonance imaging (fMRI) brain imaging experiments of parents. We begin with a discussion of background, perspectives and caveats for considering the neurobiology of parent–infant relationships. Then, we discuss aspects of the psychology of parenting that are significantly motivating some of the more basic neuroscience research. Following that, we discuss some of the neurohormones that are important for the regulation of social bonding, and the dysregulation of parenting with cocaine abuse. Then, we review the brain circuitry underlying parenting, proceeding from relevant rodent and nonhuman primate research to human work. Finally, we focus on a study-by-study review of functional neuroimaging studies in humans. Taken together, this research suggests that networks of highly conserved hypothalamic–midbrain–limbic–paralimbic–cortical circuits act in concert to support aspects of parent response to infants, including the emotion, attention, motivation, empathy, decision-making and other thinking that are required to navigate the complexities of parenting. Specifically, infant stimuli activate basal forebrain regions, which regulate brain circuits that handle specific nurturing and caregiving responses and activate the brain’s more general circuitry for handling emotions, motivation, attention, and empathy – all of which are crucial for effective parenting. We argue that an integrated understanding of the brain basis of parenting has profound implications for mental health. PMID:17355399

  20. Functional Analyses and Treatment of Precursor Behavior

    ERIC Educational Resources Information Center

    Najdowski, Adel C.; Wallace, Michele D.; Ellsworth, Carrie L.; MacAleese, Alicia N.; Cleveland, Jackie

    2008-01-01

    Functional analysis has been demonstrated to be an effective method to identify environmental variables that maintain problem behavior. However, there are cases when conducting functional analyses of severe problem behavior may be contraindicated. The current study applied functional analysis procedures to a class of behavior that preceded severe…

  1. Dreaming as mind wandering: evidence from functional neuroimaging and first-person content reports

    PubMed Central

    Fox, Kieran C. R.; Nijeboer, Savannah; Solomonova, Elizaveta; Domhoff, G. William; Christoff, Kalina

    2013-01-01

    Isolated reports have long suggested a similarity in content and thought processes across mind wandering (MW) during waking, and dream mentation during sleep. This overlap has encouraged speculation that both “daydreaming” and dreaming may engage similar brain mechanisms. To explore this possibility, we systematically examined published first-person experiential reports of MW and dreaming and found many similarities: in both states, content is largely audiovisual and emotional, follows loose narratives tinged with fantasy, is strongly related to current concerns, draws on long-term memory, and simulates social interactions. Both states are also characterized by a relative lack of meta-awareness. To relate first-person reports to neural evidence, we compared meta-analytic data from numerous functional neuroimaging (PET, fMRI) studies of the default mode network (DMN, with high chances of MW) and rapid eye movement (REM) sleep (with high chances of dreaming). Our findings show large overlaps in activation patterns of cortical regions: similar to MW/DMN activity, dreaming and REM sleep activate regions implicated in self-referential thought and memory, including medial prefrontal cortex (PFC), medial temporal lobe structures, and posterior cingulate. Conversely, in REM sleep numerous PFC executive regions are deactivated, even beyond levels seen during waking MW. We argue that dreaming can be understood as an “intensified” version of waking MW: though the two share many similarities, dreams tend to be longer, more visual and immersive, and to more strongly recruit numerous key hubs of the DMN. Further, whereas MW recruits fewer PFC regions than goal-directed thought, dreaming appears to be characterized by an even deeper quiescence of PFC regions involved in cognitive control and metacognition, with a corresponding lack of insight and meta-awareness. We suggest, then, that dreaming amplifies the same features that distinguish MW from goal-directed waking

  2. Multimodal neuroimaging evidence of alterations in cortical structure and function in HIV-infected older adults

    PubMed Central

    Wilson, Tony W.; Heinrichs-Graham, Elizabeth; Becker, Katherine M.; Aloi, Joey; Robertson, Kevin R.; Sandkovsky, Uriel; White, Matthew L.; O’Neill, Jennifer; Knott, Nichole L.; Fox, Howard S.; Swindells, Susan

    2015-01-01

    Combination antiretroviral therapy transformed HIV-infection from a terminal illness to a manageable condition, but these patients remain at a significantly elevated risk of developing cognitive impairments and the mechanisms are not understood. Some previous neuroimaging studies have found hyperactivation in fronto-parietal networks of HIV-infected patients, whereas others reported aberrations restricted to sensory cortices. In this study, we utilize high-resolution structural and neurophysiological imaging to determine whether alterations in brain structure, function, or both contribute to HIV-related cognitive impairments. HIV-infected adults and individually-matched controls completed 3-Tesla structural magnetic-resonance imaging (sMRI) and a mechanoreception task during magnetoencephalography (MEG). MEG data was examined using advanced beamforming methods, and sMRI data was analyzed using the latest voxel-based morphometry methods with DARTEL. We found significantly reduced theta responses in the postcentral gyrus and increased alpha activity in the prefrontal cortices of HIV-infected patients compared with controls. Patients also had reduced gray matter volume in the postcentral gyrus, parahippocampal gyrus, and other regions. Importantly, reduced gray matter volume in the left postcentral gyrus was spatially-coincident with abnormal MEG responses in HIV-infected patients. Finally, left prefrontal and postcentral gyrus activity was correlated with neuropsychological performance and, when used in conjunction, these two MEG findings had a sensitivity and specificity of over 87.5% for HIV-associated cognitive impairment. This study is the first to demonstrate abnormally increased activity in association cortices with simultaneously decreased activity in sensory areas. These MEG findings had excellent sensitivity and specificity for HIV-associated cognitive impairment, and may hold promise as a potential disease marker. PMID:25376125

  3. Interactive graphics for functional data analyses.

    PubMed

    Wrobel, Julia; Park, So Young; Staicu, Ana Maria; Goldsmith, Jeff

    Although there are established graphics that accompany the most common functional data analyses, generating these graphics for each dataset and analysis can be cumbersome and time consuming. Often, the barriers to visualization inhibit useful exploratory data analyses and prevent the development of intuition for a method and its application to a particular dataset. The refund.shiny package was developed to address these issues for several of the most common functional data analyses. After conducting an analysis, the plot shiny() function is used to generate an interactive visualization environment that contains several distinct graphics, many of which are updated in response to user input. These visualizations reduce the burden of exploratory analyses and can serve as a useful tool for the communication of results to non-statisticians.

  4. Addressing reverse inference in psychiatric neuroimaging: Meta-analyses of task-related brain activation in common mental disorders.

    PubMed

    Sprooten, Emma; Rasgon, Alexander; Goodman, Morgan; Carlin, Ariella; Leibu, Evan; Lee, Won Hee; Frangou, Sophia

    2017-04-01

    Functional magnetic resonance imaging (fMRI) studies in psychiatry use various tasks to identify case-control differences in the patterns of task-related brain activation. Differently activated regions are often ascribed disorder-specific functions in an attempt to link disease expression and brain function. We undertook a systematic meta-analysis of data from task-fMRI studies to examine the effect of diagnosis and study design on the spatial distribution and direction of case-control differences on brain activation. We mapped to atlas regions coordinates of case-control differences derived from 537 task-fMRI studies in schizophrenia, bipolar disorder, major depressive disorder, anxiety disorders, and obsessive compulsive disorder comprising observations derived from 21,427 participants. The fMRI tasks were classified according to the Research Domain Criteria (RDoC). We investigated whether diagnosis, RDoC domain or construct and use of regions-of-interest or whole-brain analyses influenced the neuroanatomical pattern of results. When considering all primary studies, we found an effect of diagnosis for the amygdala and caudate nucleus and an effect of RDoC domains and constructs for the amygdala, hippocampus, putamen and nucleus accumbens. In contrast, whole-brain studies did not identify any significant effect of diagnosis or RDoC domain or construct. These results resonate with prior reports of common brain structural and genetic underpinnings across these disorders and caution against attributing undue specificity to brain functional changes when forming explanatory models of psychiatric disorders. Hum Brain Mapp 38:1846-1864, 2017. © 2017 Wiley Periodicals, Inc.

  5. Addressing reverse inference in psychiatric neuroimaging: Meta‐analyses of task‐related brain activation in common mental disorders

    PubMed Central

    Sprooten, Emma; Rasgon, Alexander; Goodman, Morgan; Carlin, Ariella; Leibu, Evan; Lee, Won Hee

    2017-01-01

    Abstract Functional magnetic resonance imaging (fMRI) studies in psychiatry use various tasks to identify case‐control differences in the patterns of task‐related brain activation. Differently activated regions are often ascribed disorder‐specific functions in an attempt to link disease expression and brain function. We undertook a systematic meta‐analysis of data from task‐fMRI studies to examine the effect of diagnosis and study design on the spatial distribution and direction of case‐control differences on brain activation. We mapped to atlas regions coordinates of case‐control differences derived from 537 task‐fMRI studies in schizophrenia, bipolar disorder, major depressive disorder, anxiety disorders, and obsessive compulsive disorder comprising observations derived from 21,427 participants. The fMRI tasks were classified according to the Research Domain Criteria (RDoC). We investigated whether diagnosis, RDoC domain or construct and use of regions‐of‐interest or whole‐brain analyses influenced the neuroanatomical pattern of results. When considering all primary studies, we found an effect of diagnosis for the amygdala and caudate nucleus and an effect of RDoC domains and constructs for the amygdala, hippocampus, putamen and nucleus accumbens. In contrast, whole‐brain studies did not identify any significant effect of diagnosis or RDoC domain or construct. These results resonate with prior reports of common brain structural and genetic underpinnings across these disorders and caution against attributing undue specificity to brain functional changes when forming explanatory models of psychiatric disorders. Hum Brain Mapp 38:1846–1864, 2017. © 2017 Wiley Periodicals, Inc. PMID:28067006

  6. Neuroimaging in Pediatric Traumatic Brain Injury: Current and Future Predictors of Functional Outcome

    ERIC Educational Resources Information Center

    Suskauer, Stacy J.; Huisman, Thierry A. G. M.

    2009-01-01

    Although neuroimaging has long played a role in the acute management of pediatric traumatic brain injury (TBI), until recently, its use as a tool for understanding and predicting long-term brain-behavior relationships after TBI has been limited by the relatively poor sensitivity of routine clinical imaging for detecting diffuse axonal injury…

  7. Examining Reading Development and Reading Disability in English Language Learners: Potential Contributions from Functional Neuroimaging

    ERIC Educational Resources Information Center

    Pugh, Kenneth R.; Sandak, Rebecca; Frost, Stephen J.; Moore, Dina; Mencl, W. Einar

    2005-01-01

    Neuroimaging studies have suggested that across different written languages, skilled reading behavior is supported by similar, largely left hemisphere (LH), networks. In addition, recent studies of reading disability (RD) in monolingual readers, conducted in several languages, suggest a common neurobiological signature for this syndrome…

  8. Neuroimaging of epilepsy

    PubMed Central

    Cendes, Fernando; Theodore, William H.; Brinkmann, Benjamin H.; Sulc, Vlastimil; Cascino, Gregory D.

    2017-01-01

    Imaging is pivotal in the evaluation and management of patients with seizure disorders. Elegant structural neuroimaging with magnetic resonance imaging (MRI) may assist in determining the etiology of focal epilepsy and demonstrating the anatomical changes associated with seizure activity. The high diagnostic yield of MRI to identify the common pathological findings in individuals with focal seizures including mesial temporal sclerosis, vascular anomalies, low-grade glial neoplasms and malformations of cortical development has been demonstrated. Positron emission tomography (PET) is the most commonly performed interictal functional neuroimaging technique that may reveal a focal hypometabolic region concordant with seizure onset. Single photon emission computed tomography (SPECT) studies may assist performance of ictal neuroimaging in patients with pharmacoresistant focal epilepsy being considered for neurosurgical treatment. This chapter highlights neuroimaging developments and innovations, and provides a comprehensive overview of the imaging strategies used to improve the care and management of people with epilepsy. PMID:27430454

  9. The use of functional neuroimaging to evaluate psychological and other non-pharmacological treatments for clinical pain

    PubMed Central

    Jensen, Karin B.; Berna, Chantal; Loggia, Marco L.; Wasan, Ajay; Edwards, Robert R.; Gollub, Randy L.

    2013-01-01

    A large number of studies have provided evidence for the efficacy of psychological and other non-pharmacological interventions in the treatment of chronic pain. While these methods are increasingly used to treat pain, remarkably few studies focused on the exploration of their neural correlates. The aim of this article was to review the findings from neuroimaging studies that evaluated the neural response to distraction-based techniques, cognitive behavioral therapy (CBT), clinical hypnosis, mental imagery, physical therapy/exercise, biofeedback, and mirror therapy. To date, the results from studies that used neuroimaging to evaluate these methods have not been conclusive and the experimental methods have been suboptimal for assessing clinical pain. Still, several different psychological and non-pharmacological treatment modalities were associated with increased painrelated activations of executive cognitive brain regions, such as the ventral- and dorsolateral prefrontal cortex. There was also evidence for decreased pain-related activations in afferent pain regions and limbic structures. If future studies will address the technical and methodological challenges of today’s experiments, neuroimaging might have the potential of segregating the neural mechanisms of different treatment interventions and elucidate predictive and mediating factors for successful treatment outcomes. Evaluations of treatment-related brain changes (functional and structural) might also allow for sub-grouping of patients and help to develop individualized treatments. PMID:22445888

  10. Functional neuroimaging with default mode network regions distinguishes PTSD from TBI in a military veteran population.

    PubMed

    Raji, Cyrus A; Willeumier, Kristen; Taylor, Derek; Tarzwell, Robert; Newberg, Andrew; Henderson, Theodore A; Amen, Daniel G

    2015-09-01

    % sensitivity, 69 % specificity, and 81 % accuracy. For separating PTSD from PTSD/TBI baseline scans had 87 % sensitivity, 83 % specificity, and 92 % accuracy. Concentration scans had 91 % sensitivity, 76 % specificity, and 88 % accuracy. Baseline-concentration scans had 84 % sensitivity, 64 % specificity, and 85 % accuracy. This study demonstrates the ability to separate PTSD and TBI from each other in a veteran population using functional neuroimaging.

  11. Correlation Functions Aid Analyses Of Spectra

    NASA Technical Reports Server (NTRS)

    Beer, Reinhard; Norton, Robert H., Jr.

    1989-01-01

    New uses found for correlation functions in analyses of spectra. In approach combining elements of both pattern-recognition and traditional spectral-analysis techniques, spectral lines identified in data appear useless at first glance because they are dominated by noise. New approach particularly useful in measurement of concentrations of rare species of molecules in atmosphere.

  12. The role(s) of astrocytes and astrocyte activity in neurometabolism, neurovascular coupling, and the production of functional neuroimaging signals.

    PubMed

    Figley, Chase R; Stroman, Patrick W

    2011-02-01

    Data acquired with functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) are often interpreted in terms of the underlying neuronal activity, despite mounting evidence that these signals do not always correlate with electrophysiological recordings. Therefore, considering the increasing popularity of functional neuroimaging, it is clear that a more comprehensive theory is needed to reconcile these apparent disparities and more accurately explain the mechanisms through which various PET and fMRI signals arise. In the present article, we have turned our attention to astrocytes, which vastly outnumber neurons and are known to serve a number of functions throughout the central nervous system (CNS). For example, astrocytes are known to be critically involved in neurotransmitter uptake and recycling, and empirical data suggests that brain activation increases both oxidative and glycolytic astrocyte metabolism. Furthermore, a number of recent studies imply that astrocytes are likely to play a key role in regulating cerebral blood delivery. Therefore, we propose that, by mediating neurometabolic and neurovascular processes throughout the CNS, astrocytes could provide a common physiological basis for fMRI and PET signals. Such a theory has significant implications for the interpretation of functional neuroimaging signals, because astrocytic changes reflect subthreshold neuronal activity, simultaneous excitatory/inhibitory synaptic inputs, and other transient metabolic demands that may not elicit electrophysiological changes. It also suggests that fMRI and PET signals may have inherently less sensitivity to decreases in synaptic input (i.e. 'negative activity') and/or inhibitory (GABAergic) neurotransmission.

  13. Meta-Analysis of Functional Neuroimaging and Cognitive Control Studies in Schizophrenia: Preliminary Elucidation of a Core Dysfunctional Timing Network

    PubMed Central

    Alústiza, Irene; Radua, Joaquim; Albajes-Eizagirre, Anton; Domínguez, Manuel; Aubá, Enrique; Ortuño, Felipe

    2016-01-01

    Timing and other cognitive processes demanding cognitive control become interlinked when there is an increase in the level of difficulty or effort required. Both functions are interrelated and share neuroanatomical bases. A previous meta-analysis of neuroimaging studies found that people with schizophrenia had significantly lower activation, relative to normal controls, of most right hemisphere regions of the time circuit. This finding suggests that a pattern of disconnectivity of this circuit, particularly in the supplementary motor area, is a trait of this mental disease. We hypothesize that a dysfunctional temporal/cognitive control network underlies both cognitive and psychiatric symptoms of schizophrenia and that timing dysfunction is at the root of the cognitive deficits observed. The goal of our study was to look, in schizophrenia patients, for brain structures activated both by execution of cognitive tasks requiring increased effort and by performance of time perception tasks. We conducted a signed differential mapping (SDM) meta-analysis of functional neuroimaging studies in schizophrenia patients assessing the brain response to increasing levels of cognitive difficulty. Then, we performed a multimodal meta-analysis to identify common brain regions in the findings of that SDM meta-analysis and our previously-published activation likelihood estimate (ALE) meta-analysis of neuroimaging of time perception in schizophrenia patients. The current study supports the hypothesis that there exists an overlap between neural structures engaged by both timing tasks and non-temporal cognitive tasks of escalating difficulty in schizophrenia. The implication is that a deficit in timing can be considered as a trait marker of the schizophrenia cognitive profile. PMID:26925013

  14. 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

  15. To BD or not to BD: functional neuroimaging and the boundaries of bipolarity.

    PubMed

    Kuiper, Sandy; McLean, Loyola; Malhi, Gin S

    2013-01-01

    Bipolar disorders are major mood disorders defined by the presence of discrete episodes of depression and either mania, in bipolar I disorder, or hypomania, in bipolar II disorder. There is little contention that both are serious psychiatric conditions or that they are associated with substantial suffering, disability, risk of suicide and cost to the community. Recently, focus has shifted away from classic manic-depressive illness toward a 'bipolar spectrum' model, which allows for much softer presentations to be conceptualized as bipolarity, but the boundaries of this concept remain contentious. In this article, we will consider the contribution of neuroimaging to delineating the bipolar phenotype and differentiating it from similar disorders.

  16. Insights from neuroenergetics into the interpretation of functional neuroimaging: an alternative empirical model for studying the brain's support of behavior

    PubMed Central

    Shulman, Robert G; Hyder, Fahmeed; Rothman, Douglas L

    2014-01-01

    Functional neuroimaging measures quantitative changes in neurophysiological parameters coupled to neuronal activity during observable behavior. These results have usually been interpreted by assuming that mental causation of behavior arises from the simultaneous actions of distinct psychological mechanisms or modules. However, reproducible localization of these modules in the brain using functional magnetic resonance imaging (MRI) and positron emission tomography (PET) imaging has been elusive other than for sensory systems. In this paper, we show that neuroenergetic studies using PET, calibrated functional magnetic resonance imaging (fMRI), 13C magnetic resonance spectroscopy, and electrical recordings do not support the standard approach, which identifies the location of mental modules from changes in brain activity. Of importance in reaching this conclusion is that changes in neuronal activities underlying the fMRI signal are many times smaller than the high ubiquitous, baseline neuronal activity, or energy in resting, awake humans. Furthermore, the incremental signal depends on the baseline activity contradicting theoretical assumptions about linearity and insertion of mental modules. To avoid these problems, while making use of these valuable results, we propose that neuroimaging should be used to identify observable brain activities that are necessary for a person's observable behavior rather than being used to seek hypothesized mental processes. PMID:25160670

  17. Exploring yawning with neuroimaging.

    PubMed

    Nahab, Fatta B

    2010-01-01

    The neural mechanisms responsible for spontaneous yawning as well as contagious yawning are not well characterized. Neuroimaging is an essential tool for helping to identify the seminal neural structures and their inter-related functions to carry out this complex stereotyped motor program. Studies to date have explored the structural neural correlates of yawning through a series of lesion-based case reports and identified participatory structures at various levels of the central nervous system. Functional neuroimaging methods like fMRI have also shed led on the genesis of contagious yawning, though cohesive models explaining the neural mechanisms of contagious motor programs such as yawning remain limited.

  18. Neuroimaging markers of cellular function in major depressive disorder: implications for therapeutics, personalized medicine, and prevention.

    PubMed

    Meyer, J H

    2012-02-01

    It is estimated that 15% of all individuals will experience a major depressive episode (MDE) during their lifetime and that treatment response is inadequate in 40% of these cases. To address this, neuroimaging is being used to identify MDE subtypes and mechanisms of onset as well as to optimize target occupancy of novel treatments. Neuroimaging of monoamine oxidase-A (MAO-A) binding; glutamate levels; indexes of 5-HT(2A), 5-HTT, 5-HT(1A), and 5-HT(1B) receptors; levels of dopamine transporters D(1) and D(2); and hippocampal volume are described here. Three themes emerge. First, symptoms such as pessimism, motor retardation, anxiety disorder, and verbal memory deficits best indicate the subtype of depression. Second, measures related to mechanisms of monoamine loss, particularly elevated MAO-A binding in prefrontal and anterior cingulate cortex, are present in MDE and in high-risk states for MDE. Third, clinical trials show a consistent 80% 5-HTT occupancy of selective serotonin reuptake inhibitors at doses sufficient to distinguish from placebo in clinical trials (although in vitro affinities vary 100-fold), thereby supporting the need for further occupancy studies to accelerate therapeutic development.

  19. Progression of limb apraxia in corticobasal syndrome: neuropychological and functional neuroimaging report of a case series.

    PubMed

    Stamenova, Vessela; Roy, Eric A; Szilagyi, Gregory; Honjo, Kie; Black, Sandra E; Masellis, Mario

    2015-01-01

    The current study described the progression of limb apraxia in seven corticobasal syndrome patients through a comprehensive battery, including both gesture production tasks and conceptual tool/action knowledge tasks. The examination of the behavioral and neuroimaging (SPECT) data revealed two patient subgroups. One group consisted of patients with preserved conceptual tool/action knowledge, relatively mild gesture production and neuropsychological deficits with few significantly hypoperfused regions of interest. The other group consisted of those whose conceptual tool/action knowledge and general cognition eventually deteriorated and who were quite severely affected in their gesture production performance. These patients were characterized by bilateral hypoperfusion in parietal regions and in one case bilateral anterior cingulate regions.

  20. Investigating Human Neurovascular Coupling Using Functional Neuroimaging: A Critical Review of Dynamic Models

    PubMed Central

    Huneau, Clément; Benali, Habib; Chabriat, Hugues

    2015-01-01

    The mechanisms that link a transient neural activity to the corresponding increase of cerebral blood flow (CBF) are termed neurovascular coupling (NVC). They are possibly impaired at early stages of small vessel or neurodegenerative diseases. Investigation of NVC in humans has been made possible with the development of various neuroimaging techniques based on variations of local hemodynamics during neural activity. Specific dynamic models are currently used for interpreting these data that can include biophysical parameters related to NVC. After a brief review of the current knowledge about possible mechanisms acting in NVC we selected seven models with explicit integration of NVC found in the literature. All these models were described using the same procedure. We compared their physiological assumptions, mathematical formalism, and validation. In particular, we pointed out their strong differences in terms of complexity. Finally, we discussed their validity and their potential applications. These models may provide key information to investigate various aspects of NVC in human pathology. PMID:26733782

  1. Investigating Human Neurovascular Coupling Using Functional Neuroimaging: A Critical Review of Dynamic Models.

    PubMed

    Huneau, Clément; Benali, Habib; Chabriat, Hugues

    2015-01-01

    The mechanisms that link a transient neural activity to the corresponding increase of cerebral blood flow (CBF) are termed neurovascular coupling (NVC). They are possibly impaired at early stages of small vessel or neurodegenerative diseases. Investigation of NVC in humans has been made possible with the development of various neuroimaging techniques based on variations of local hemodynamics during neural activity. Specific dynamic models are currently used for interpreting these data that can include biophysical parameters related to NVC. After a brief review of the current knowledge about possible mechanisms acting in NVC we selected seven models with explicit integration of NVC found in the literature. All these models were described using the same procedure. We compared their physiological assumptions, mathematical formalism, and validation. In particular, we pointed out their strong differences in terms of complexity. Finally, we discussed their validity and their potential applications. These models may provide key information to investigate various aspects of NVC in human pathology.

  2. Acute and non-acute effects of cannabis on human memory function: a critical review of neuroimaging studies.

    PubMed

    Bossong, Matthijs G; Jager, Gerry; Bhattacharyya, Sagnik; Allen, Paul

    2014-01-01

    Smoking cannabis produces a diverse range of effects, including impairments in learning and memory. These effects are exerted through action on the endocannabinoid system, which suggests involvement of this system in human cognition. Learning and memory deficits are core symptoms of psychiatric and neurological disorders such as schizophrenia and Alzheimer's disease, and may also be related to endocannabinoid dysfunction in these disorders. However, before new research can focus on potential treatments that work by manipulating the endocannabinoid system, it needs to be elucidated how this system is involved in symptoms of psychiatric disorders. Here we review neuroimaging studies that investigated acute and non-acute effects of cannabis on human learning and memory function, both in adults and in adolescents. Overall, results of these studies show that cannabis use is associated with a pattern of increased activity and a higher level of deactivation in different memory-related areas. This could reflect either increased neural effort ('neurophysiological inefficiency') or a change in strategy to maintain good task performance. However, the interpretation of these findings is significantly hampered by large differences between study populations in cannabis use in terms of frequency, age of onset, and time that subjects were abstinent from cannabis. Future neuroimaging studies should take these limitations into account, and should focus on the potential of cannabinoid compounds for treatment of cognitive symptoms in psychiatric disorders.

  3. Neuroimaging and Aggression.

    ERIC Educational Resources Information Center

    Mills, Shari; Raine, Adrian

    1994-01-01

    Brain imaging research allows direct assessment of structural and functional brain abnormalities, and thereby provides an improved methodology for studying neurobiological factors predisposing to violent and aggressive behavior. This paper reviews 20 brain imaging studies using four different types of neuroimaging techniques that were conducted in…

  4. Getting the timing right: experimental protocols for investigating time with functional neuroimaging and psychopharmacology.

    PubMed

    Coull, Jennifer T

    2014-01-01

    Functional Magnetic Resonance Imaging (fMRI) is an effective tool for identifying brain areas and networks implicated in human timing. But fMRI is not just a phrenological tool: by careful design, fMRI can be used to disentangle discrete components of a timing task and control for the underlying cognitive processes (e.g. sustained attention and WM updating) that are critical for estimating stimulus duration in the range of hundreds of milliseconds to seconds. Moreover, the use of parametric designs and correlational analyses allows us to better understand not just where, but also how, the brain processes temporal information. In addition, by combining fMRI with psychopharmacological manipulation, we can begin to uncover the complex relationship between cognition, neurochemistry and anatomy in the healthy human brain. This chapter provides an overview of some of the key findings in the functional imaging literature of both duration estimation and temporal prediction, and outlines techniques that can be used to allow timing-related activations to be interpreted more unambiguously. In our own studies, we have found that estimating event duration, whether that estimate is provided by a motor response or a perceptual discrimination, typically recruits basal ganglia, SMA and right inferior frontal cortex, and can be modulated by dopaminergic activity in these areas. By contrast, orienting attention to predictable moments in time in order to optimize behaviour, whether that is to speed motor responding or improve perceptual accuracy, recruits left inferior parietal cortex.

  5. Data sharing in neuroimaging research

    PubMed Central

    Poline, Jean-Baptiste; Breeze, Janis L.; Ghosh, Satrajit; Gorgolewski, Krzysztof; Halchenko, Yaroslav O.; Hanke, Michael; Haselgrove, Christian; Helmer, Karl G.; Keator, David B.; Marcus, Daniel S.; Poldrack, Russell A.; Schwartz, Yannick; Ashburner, John; Kennedy, David N.

    2012-01-01

    Significant resources around the world have been invested in neuroimaging studies of brain function and disease. Easier access to this large body of work should have profound impact on research in cognitive neuroscience and psychiatry, leading to advances in the diagnosis and treatment of psychiatric and neurological disease. A trend toward increased sharing of neuroimaging data has emerged in recent years. Nevertheless, a number of barriers continue to impede momentum. Many researchers and institutions remain uncertain about how to share data or lack the tools and expertise to participate in data sharing. The use of electronic data capture (EDC) methods for neuroimaging greatly simplifies the task of data collection and has the potential to help standardize many aspects of data sharing. We review here the motivations for sharing neuroimaging data, the current data sharing landscape, and the sociological or technical barriers that still need to be addressed. The INCF Task Force on Neuroimaging Datasharing, in conjunction with several collaborative groups around the world, has started work on several tools to ease and eventually automate the practice of data sharing. It is hoped that such tools will allow researchers to easily share raw, processed, and derived neuroimaging data, with appropriate metadata and provenance records, and will improve the reproducibility of neuroimaging studies. By providing seamless integration of data sharing and analysis tools within a commodity research environment, the Task Force seeks to identify and minimize barriers to data sharing in the field of neuroimaging. PMID:22493576

  6. Cognitive control for language switching in bilinguals: A quantitative meta-analysis of functional neuroimaging studies

    PubMed Central

    Luk, Gigi; Green, David W.; Abutalebi, Jubin; Grady, Cheryl

    2013-01-01

    In a quantitative meta-analysis, using the activation likelihood estimation method, we examined the neural regions involved in bilingual cognitive control, particularly when engaging in switching between languages. The purpose of this study was to evaluate the bilingual cognitive control model based on a qualitative analysis [Abutalebi, J., & Green, D. W. (2008). Control mechanisms in bilingual language production: Neural evidence from language switching studies. Language and Cognitive Processes, 23, 557–582.]. After reviewing 128 peer-reviewed articles, ten neuroimaging studies met our inclusion criteria and in each study, bilinguals switched between languages in response to cues. We isolated regions involved in voluntary language switching, by including reported contrasts between the switching conditions and high level baseline conditions involving similar tasks but requiring the use of only one language. Eight brain regions showed significant and reliable activation: left inferior frontal gyrus, left middle temporal gyrus, left middle frontal gyrus, right precentral gyrus, right superior temporal gyrus, midline pre-SMA and bilateral caudate nuclei. This quantitative result is consistent with bilingual aphasia studies that report switching deficits associated with lesions to the caudate nuclei or prefrontal cortex. It also extends the previously reported qualitative model. We discuss the implications of the findings for accounts of bilingual cognitive control. PMID:24795491

  7. Assessing the reproducibility of discriminant function analyses

    PubMed Central

    Andrew, Rose L.; Albert, Arianne Y.K.; Renaut, Sebastien; Rennison, Diana J.; Bock, Dan G.

    2015-01-01

    Data are the foundation of empirical research, yet all too often the datasets underlying published papers are unavailable, incorrect, or poorly curated. This is a serious issue, because future researchers are then unable to validate published results or reuse data to explore new ideas and hypotheses. Even if data files are securely stored and accessible, they must also be accompanied by accurate labels and identifiers. To assess how often problems with metadata or data curation affect the reproducibility of published results, we attempted to reproduce Discriminant Function Analyses (DFAs) from the field of organismal biology. DFA is a commonly used statistical analysis that has changed little since its inception almost eight decades ago, and therefore provides an opportunity to test reproducibility among datasets of varying ages. Out of 100 papers we initially surveyed, fourteen were excluded because they did not present the common types of quantitative result from their DFA or gave insufficient details of their DFA. Of the remaining 86 datasets, there were 15 cases for which we were unable to confidently relate the dataset we received to the one used in the published analysis. The reasons ranged from incomprehensible or absent variable labels, the DFA being performed on an unspecified subset of the data, or the dataset we received being incomplete. We focused on reproducing three common summary statistics from DFAs: the percent variance explained, the percentage correctly assigned and the largest discriminant function coefficient. The reproducibility of the first two was fairly high (20 of 26, and 44 of 60 datasets, respectively), whereas our success rate with the discriminant function coefficients was lower (15 of 26 datasets). When considering all three summary statistics, we were able to completely reproduce 46 (65%) of 71 datasets. While our results show that a majority of studies are reproducible, they highlight the fact that many studies still are not the

  8. Working memory, reasoning, and expertise in medicine-insights into their relationship using functional neuroimaging.

    PubMed

    Hruska, Pam; Krigolson, Olav; Coderre, Sylvain; McLaughlin, Kevin; Cortese, Filomeno; Doig, Christopher; Beran, Tanya; Wright, Bruce; Hecker, Kent G

    2016-12-01

    Clinical reasoning is dependent upon working memory (WM). More precisely, during the clinical reasoning process stored information within long-term memory is brought into WM to facilitate the internal deliberation that affords a clinician the ability to reason through a case. In the present study, we examined the relationship between clinical reasoning and WM while participants read clinical cases with functional magnetic resonance imaging (fMRI). More specifically, we examined the impact of clinical case difficulty (easy, hard) and clinician level of expertise (2nd year medical students, senior gastroenterologists) on neural activity within regions of cortex associated with WM (i.e., the prefrontal cortex) during the reasoning process. fMRI was used to scan ten second-year medical students and ten practicing gastroenterologists while they reasoned through sixteen clinical cases [eight straight forward (easy) and eight complex (hard)] during a single 1-h scanning session. Within-group analyses contrasted the easy and hard cases which were then subsequently utilized for a between-group analysis to examine effects of expertise (novice > expert, expert > novice). Reading clinical cases evoked multiple neural activations in occipital, prefrontal, parietal, and temporal cortical regions in both groups. Importantly, increased activation in the prefrontal cortex in novices for both easy and hard clinical cases suggests novices utilize WM more so than experts during clinical reasoning. We found that clinician level of expertise elicited differential activation of regions of the human prefrontal cortex associated with WM during clinical reasoning. This suggests there is an important relationship between clinical reasoning and human WM. As such, we suggest future models of clinical reasoning take into account that the use of WM is not consistent throughout all clinical reasoning tasks, and that memory structure may be utilized differently based on level of expertise.

  9. Towards a functional neuroanatomy of conscious perception and its modulation by volition: implications of human auditory neuroimaging studies.

    PubMed Central

    Silbersweig, D A; Stern, E

    1998-01-01

    Conscious sensory perception and its modulation by volition are integral to human mental life. Functional neuroimaging techniques provide a direct means of identifying and characterizing in vivo the systems-level patterns of brain activity associated with such mental functions. In a series of positron emission tomography activation experiments, we and our colleagues have examined a range of normal and abnormal auditory states that, when contrasted, provide dissociations relevant to the question of the neural substrates of sensory awareness. These dissociations include sensory awareness in the presence and absence of external sensory stimuli, the transition from sensory unawareness to awareness (or vice versa) in the presence of sensory stimuli, and sensory awareness with and without volition. The auditory states studied include hallucinations, mental imagery, cortical deafness modulated by attention, and hearing modulated by sedation. The results of these studies highlight the distributed nature of the functional neuroanatomy that is sufficient, if not necessary, for sensory awareness. The probable roles of unimodal association (as compared with primary) cortices, heteromodal cortices, limbic/paralimbic regions and subcortical structures (such as the thalamus) are discussed. In addition, interactions between pre- and post-rolandic regions are examined in the context of top-down, volitional modulation of sensory awareness. PMID:9854260

  10. Functional near infrared spectroscopy (fNIRS): an emerging neuroimaging technology with important applications for the study of brain disorders.

    PubMed

    Irani, Farzin; Platek, Steven M; Bunce, Scott; Ruocco, Anthony C; Chute, Douglas

    2007-01-01

    Functional near-infrared spectroscopy (fNIRS) is an emerging functional neuroimaging technology offering a relatively non-invasive, safe, portable, and low-cost method of indirect and direct monitoring of brain activity. Most exciting is its potential to allow more ecologically valid investigations that can translate laboratory work into more realistic everyday settings and clinical environments. Our aim is to acquaint clinicians and researchers with the unique and beneficial characteristics of fNIRS by reviewing its relative merits and limitations vis-à-vis other brain-imaging technologies such as functional magnetic resonance imaging (fMRI). We review cross-validation work between fMRI and fNIRS, and discuss possible reservations about its deployment in clinical research and practice. Finally, because there is no comprehensive review of applications of fNIRS to brain disorders, we also review findings from the few studies utilizing fNIRS to investigate neurocognitive processes associated with neurological (Alzheimer's disease, Parkinson's disease, epilepsy, traumatic brain injury) and psychiatric disorders (schizophrenia, mood disorders, anxiety disorders).

  11. Baby Stimuli and the Parent Brain: Functional Neuroimaging of the Neural Substrates of Parent-Infant Attachment

    PubMed Central

    Swain, James E.

    2008-01-01

    Interacting parenting thoughts and behaviors critically shape human infants’ current and future behavior. Indeed, the parent-infant relationship provides infants with their first social environment, forming templates for what they can expect from others and how best to interact with them. This paper focuses on the functional magnetic resonance imaging (fMRI) experiments relevant to the study of the brain-basis of parenting. First there is a brief introduction to techniques and a selective review of functional neuroimaging studies that examine fMRI responses to infant stimuli: baby sounds or visuals. Next, there is a sample single-subject set of brain imaging data of brain response to own-baby-cry. Finally, there is a proposed model of how infant stimuli activate parent brain circuits, including sensory analysis brain regions, as well as corticolimbic circuits that regulate motivation, reward, and learning about their infants, and ultimately organize parenting impulses, thoughts, and emotions into coordinated behaviors. It is argued that an integrated understanding of the brain basis of parenting has profound implications for understanding long-term parent and infant mental health risk and resilience. PMID:19727273

  12. Neuroimaging in anxiety disorders.

    PubMed

    Engel, Kirsten; Bandelow, Borwin; Gruber, Oliver; Wedekind, Dirk

    2009-06-01

    Neuroimaging studies have gained increasing importance in validating neurobiological network hypotheses for anxiety disorders. Functional imaging procedures and radioligand binding studies in healthy subjects and in patients with anxiety disorders provide growing evidence of the existence of a complex anxiety network, including limbic, brainstem, temporal, and prefrontal cortical regions. Obviously, "normal anxiety" does not equal "pathological anxiety" although many phenomena are evident in healthy subjects, however to a lower extent. Differential effects of distinct brain regions and lateralization phenomena in different anxiety disorders are mentioned. An overview of neuroimaging investigations in anxiety disorders is given after a brief summary of results from healthy volunteers. Concluding implications for future research are made by the authors.

  13. Genes that affect brain structure and function identified by rare variant analyses of Mendelian neurologic disease

    PubMed Central

    Karaca, Ender; Harel, Tamar; Pehlivan, Davut; Jhangiani, Shalini N.; Gambin, Tomasz; Akdemir, Zeynep Coban; Gonzaga-Jauregui, Claudia; Erdin, Serkan; Bayram, Yavuz; Campbell, Ian M.; Hunter, Jill V.; Atik, Mehmed M.; Van Esch, Hilde; Yuan, Bo; Wiszniewski, Wojciech; Isikay, Sedat; Yesil, Gozde; Yuregir, Ozge O.; Bozdogan, Sevcan Tug; Aslan, Huseyin; Aydin, Hatip; Tos, Tulay; Aksoy, Ayse; De Vivo, Darryl C.; Jain, Preti; Geckinli, B. Bilge; Sezer, Ozlem; Gul, Davut; Durmaz, Burak; Cogulu, Ozgur; Ozkinay, Ferda; Topcu, Vehap; Candan, Sukru; Cebi, Alper Han; Ikbal, Mevlit; Gulec, Elif Yilmaz; Gezdirici, Alper; Koparir, Erkan; Ekici, Fatma; Coskun, Salih; Cicek, Salih; Karaer, Kadri; Koparir, Asuman; Duz, Mehmet Bugrahan; Kirat, Emre; Fenercioglu, Elif; Ulucan, Hakan; Seven, Mehmet; Guran, Tulay; Elcioglu, Nursel; Yildirim, Mahmut Selman; Aktas, Dilek; Alikaşifoğlu, Mehmet; Ture, Mehmet; Yakut, Tahsin; Overton, John D.; Yuksel, Adnan; Ozen, Mustafa; Muzny, Donna M.; Adams, David R.; Boerwinkle, Eric; Chung, Wendy K.; Gibbs, Richard A.; Lupski, James R

    2015-01-01

    Development of the human nervous system involves complex interactions between fundamental cellular processes and requires a multitude of genes, many of which remain to be associated with human disease. We applied whole exome sequencing to 128 mostly consanguineous families with neurogenetic disorders that often included brain malformations. Rare variant analyses for both single nucleotide variant (SNV) and copy number variant (CNV) alleles allowed for identification of 45 novel variants in 43 known disease genes, 41 candidate genes, and CNVs in 10 families, with an overall potential molecular cause identified in >85% of families studied. Among the candidate genes identified, we found PRUNE, VARS, and DHX37 in multiple families, and homozygous loss of function variants in AGBL2, SLC18A2, SMARCA1, UBQLN1, and CPLX1. Neuroimaging and in silico analysis of functional and expression proximity between candidate and known disease genes allowed for further understanding of genetic networks underlying specific types of brain malformations. PMID:26539891

  14. Development of large-scale functional networks from birth to adulthood: a guide to neuroimaging literature.

    PubMed

    Grayson, David S; Fair, Damien A

    2017-02-01

    The development of human cognition results from the emergence of coordinated brain activity betweeen distant brain areas. Network science, combined with non-invasive functional imaging, has generated unprecedented insights regarding the adult brain's functional organization, and promises to help elucidate the development of functional architectures supporting complex behavior. Here we review what is known about functional network development from birth until adulthood, particularly as understood through the use of resting-state functional connectivity MRI (rs-fcMRI). We attempt to synthesize rs-fcMRI findings with other functional imaging techniques, with macro-scale structural connectivity, and with knowledge regarding the development of micro-scale structure. We highlight a number of outstanding conceptual and technical barriers that need to be addressed, as well as previous developmental findings that may need to be revisited. Finally, we discuss key areas ripe for future research in order to 1) better characterize normative developmental trajectories, 2) link these trajectories to biologic mechanistic events, as well as component behaviors and 3) better understand the clinical implications and pathophysiological basis of aberrant network development.

  15. Effect of Psychostimulants on Brain Structure and Function in ADHD: A Qualitative Literature Review of MRI-Based Neuroimaging Studies

    PubMed Central

    Spencer, Thomas J.; Brown, Ariel; Seidman, Larry J.; Valera, Eve M.; Makris, Nikos; Lomedico, Alexandra; Faraone, Stephen V.; Biederman, Joseph

    2013-01-01

    Objective To evaluate the impact of therapeutic oral doses of stimulants on the brains of ADHD subjects as measured by MRI-based neuroimaging studies (morphometric, functional, spectroscopy). Data Sources We searched PubMed and ScienceDirect through the end of calendar year 2011 using the keywords: 1) “psychostimulants” or “methylphenidate” or “amphetamine”, and 2) “neuroimaging” or “MRI” or “fMRI”, and 3) “ADHD” or “ADD” or “Attention-Deficit/Hyperactivity Disorder” or “Attention Deficit Hyperactivity Disorder”. Study Selection We included only English language articles with new data that were case or placebo-controlled and examined ADHD subjects on and off psychostimulants (as well as 5 relevant review papers). Data Extraction We combined details of study design and medication effects in each imaging modality. Results We found 29 published studies that met our criteria. These included 6 structural MRI, 20 functional MRI studies and 3 spectroscopy studies. Methods varied widely in terms of design, analytic technique, and regions of the brain investigated. Despite heterogeneity in methods, however, results were consistent. With only a few exceptions, the data on the effect of therapeutic oral doses of stimulant medication suggest attenuation of structural and functional alterations found in unmedicated ADHD subjects relative to findings in Controls. Conclusions Despite the inherent limitations and heterogeneity of the extant MRI literature, our review suggests that therapeutic oral doses of stimulants decrease alterations in brain structure and function in subjects with ADHD relative to unmedicated subjects and Controls. These medication-associated brain effects parallel, and may underlie, the well-established clinical benefits. PMID:24107764

  16. A problem-solving task specialized for functional neuroimaging: validation of the Scarborough adaptation of the Tower of London (S-TOL) using near-infrared spectroscopy

    PubMed Central

    Ruocco, Anthony C.; Rodrigo, Achala H.; Lam, Jaeger; Di Domenico, Stefano I.; Graves, Bryanna; Ayaz, Hasan

    2014-01-01

    Problem-solving is an executive function subserved by a network of neural structures of which the dorsolateral prefrontal cortex (DLPFC) is central. Whereas several studies have evaluated the role of the DLPFC in problem-solving, few standardized tasks have been developed specifically for use with functional neuroimaging. The current study adapted a measure with established validity for the assessment of problem-solving abilities to design a test more suitable for functional neuroimaging protocols. The Scarborough adaptation of the Tower of London (S-TOL) was administered to 38 healthy adults while hemodynamic oxygenation of the PFC was measured using 16-channel continuous-wave functional near-infrared spectroscopy (fNIRS). Compared to a baseline condition, problems that required two or three steps to achieve a goal configuration were associated with higher activation in the left DLPFC and deactivation in the medial PFC. Individuals scoring higher in trait deliberation showed consistently higher activation in the left DLPFC regardless of task difficulty, whereas individuals lower in this trait displayed less activation when solving simple problems. Based on these results, the S-TOL may serve as a standardized task to evaluate problem-solving abilities in functional neuroimaging studies. PMID:24734017

  17. A problem-solving task specialized for functional neuroimaging: validation of the Scarborough adaptation of the Tower of London (S-TOL) using near-infrared spectroscopy.

    PubMed

    Ruocco, Anthony C; Rodrigo, Achala H; Lam, Jaeger; Di Domenico, Stefano I; Graves, Bryanna; Ayaz, Hasan

    2014-01-01

    Problem-solving is an executive function subserved by a network of neural structures of which the dorsolateral prefrontal cortex (DLPFC) is central. Whereas several studies have evaluated the role of the DLPFC in problem-solving, few standardized tasks have been developed specifically for use with functional neuroimaging. The current study adapted a measure with established validity for the assessment of problem-solving abilities to design a test more suitable for functional neuroimaging protocols. The Scarborough adaptation of the Tower of London (S-TOL) was administered to 38 healthy adults while hemodynamic oxygenation of the PFC was measured using 16-channel continuous-wave functional near-infrared spectroscopy (fNIRS). Compared to a baseline condition, problems that required two or three steps to achieve a goal configuration were associated with higher activation in the left DLPFC and deactivation in the medial PFC. Individuals scoring higher in trait deliberation showed consistently higher activation in the left DLPFC regardless of task difficulty, whereas individuals lower in this trait displayed less activation when solving simple problems. Based on these results, the S-TOL may serve as a standardized task to evaluate problem-solving abilities in functional neuroimaging studies.

  18. Prefrontal Cortex and Executive Functions in Healthy Adults: A Meta-Analysis of Structural Neuroimaging Studies

    PubMed Central

    Yuan, Peng; Raz, Naftali

    2014-01-01

    Lesion studies link the prefrontal cortex (PFC) to executive functions. However, the evidence from in vivo investigations in healthy people is mixed, and there are no quantitative estimates of the association strength. To examine the relationship between PFC volume and cortical thickness with executive cognition in healthy adults, we conducted a meta-analysis of studies that assessed executive functions and PFC volume (31 samples,) and PFC thickness (10 samples) in vivo, N=3272 participants. We found that larger PFC volume and greater PFC thickness were associated with better executive performance. Stronger associations between executive functions and PFC volume were linked to greater variance in the sample age but was unrelated to the mean age of a sample. Strength of association between cognitive and neuroanatomical indices depended on the executive task used in the study. PFC volume correlated stronger with Wisconsin Card Sorting Test than with digit backwards span, Trail Making Test and verbal fluency. Significant effect size was observed in lateral and medial but not orbital PFC. The results support the “bigger is better” hypothesis of brain-behavior relation in healthy adults and suggest different neural correlates across the neuropsychological tests used to assess executive functions. PMID:24568942

  19. [Strategy on dealing with noisy NIRS data: implications on functional neuroimaging on swallowing].

    PubMed

    Dan, Ippeita; Sano, Toshifumi; Dan, Haruka; Watanabe, Eiju

    2012-01-01

    Functional near-infrared spectroscopy (fNIRS) may be suited for functional monitoring during swallowing as it is comparatively immune to body movement. However, still fNIRS measurement on swallowing poses a technical problem that it may often involve motion artifacts. Although there is no single way to solve this problem, technical insights have been available form related studies in the past. Here we introduce two examples for analyzing data rich in motion artifacts putting emphasis on temporal structures of the data. The first is about fNIRS assessment of language function during overt naming tasks. Since data were temporally continuous, we adopted a general linear model with regression to a canonical hemodynamic response function to extract cortical activations related to overt naming tasks. The second example is about fNIRS assessment on go/no-go task performance with or without methylphenidate administration in Attention Deficit Hyperactivity Disorder (ADHD) children. Since data were disrupted by unexpected motion artifacts, we simplified temporal data structures by averaging to extract only robust signals. Thus, we indicated that the optimum analytical strategy varies depending on the temporal structures of the data.

  20. A functional neuroimaging review of obesity, appetitive hormones and ingestive behavior

    PubMed Central

    Burger, Kyle S.; Berner, Laura A.

    2014-01-01

    Adequate energy intake is vital for the survival of humans and is regulated by complex homeostatic and hedonic mechanisms. Supported by functional MRI (fMRI) studies that consistently demonstrate differences in brain response as a function of weight status during exposure to appetizing food stimuli, it has been posited that hedonically driven food intake contributes to weight gain and obesity maintenance. These food reward theories of obesity are reliant on the notion that the aberrant brain response to food stimuli relates directly to ingestive behavior, specifically, excess food intake. Importantly, functioning of homeostatic neuroendocrine regulators of food intake, such as leptin and ghrelin, are impacted by weight status. Thus, data from studies that evaluate the effect of weight status on brain response to food may be a result of differences in neuroendocrine functioning and/or behavior. In the present review, we examine the influence of weight and weight change, exogenous administration of appetitive hormones, and ingestive behavior on BOLD response to food stimuli. PMID:24769220

  1. Functional Neuroimaging of Speech Perception during a Pivotal Period in Language Acquisition

    ERIC Educational Resources Information Center

    Redcay, Elizabeth; Haist, Frank; Courchesne, Eric

    2008-01-01

    A pivotal period in the development of language occurs in the second year of life, when language comprehension undergoes rapid acceleration. However, the brain bases of these advances remain speculative as there is currently no functional magnetic resonance imaging (fMRI) data from healthy, typically developing toddlers at this age. We…

  2. Prefrontal cortex and executive functions in healthy adults: a meta-analysis of structural neuroimaging studies.

    PubMed

    Yuan, Peng; Raz, Naftali

    2014-05-01

    Lesion studies link the prefrontal cortex (PFC) to executive functions. However, the evidence from in vivo investigations in healthy people is mixed, and there are no quantitative estimates of the association strength. To examine the relationship between PFC volume and cortical thickness with executive cognition in healthy adults, we conducted a meta-analysis of studies that assessed executive functions and PFC volume (31 samples,) and PFC thickness (10 samples) in vivo, N=3272 participants. We found that larger PFC volume and greater PFC thickness were associated with better executive performance. Stronger associations between executive functions and PFC volume were linked to greater variance in the sample age but was unrelated to the mean age of a sample. Strength of association between cognitive and neuroanatomical indices depended on the executive task used in the study. PFC volume correlated stronger with Wisconsin Card Sorting Test than with digit backwards span, Trail Making Test and verbal fluency. Significant effect size was observed in lateral and medial but not orbital PFC. The results support the "bigger is better" hypothesis of brain-behavior relation in healthy adults and suggest different neural correlates across the neuropsychological tests used to assess executive functions.

  3. Effect of acupuncture on the brain in children with spastic cerebral palsy using functional neuroimaging (FMRI).

    PubMed

    Wu, Yun; Jin, Zhen; Li, Ke; Lu, Zhong-Li; Wong, Virginia; Han, Tong-Li; Zheng, Hua; Caspi, Opher; Liu, Gang; Zeng, Ya-Wei; Zou, Li-Ping

    2008-11-01

    We study the effect of acupuncture on brain activation patterns in children with cerebral palsy using functional magnetic resonance imaging (fMRI). fMRI of the whole brain was performed in 11 children with cerebral palsy and 10 healthy children during stimulation of a common acupoint in Traditional Medicine [Liv3 (Taichong)] on the left foot. We use both twisting and nontwisting methods with a blocked paradigm on a 2.0 Tesla MRI scanner. Functional data were analyzed by using Statistical Parametric Mapping software (SPM 99). Both signal increase and decrease in various regions of the brain were found in both groups of children. However, the pattern was different for the 2 groups, especially with decreases in signal regions. We suggest that the observed differences between children with cerebral palsy and healthy children with the stimulation of acupoint Liv3 might be due to blockage of the liver meridian in children with cerebral palsy.

  4. A functional neuroimaging study of the clinical reasoning of medical students.

    PubMed

    Chang, Hyung-Joo; Kang, June; Ham, Byung-Joo; Lee, Young-Mee

    2016-12-01

    As clinical reasoning is a fundamental competence of physicians for good clinical practices, medical academics have endeavored to teach reasoning skills to undergraduate students. However, our current understanding of student-level clinical reasoning is limited, mainly because of the lack of evaluation tools for this internal cognitive process. This functional magnetic resonance imaging (fMRI) study aimed to examine the clinical reasoning processes of medical students in response to problem-solving questions. We recruited 24 2nd-year medical students who had completed their preclinical curriculum. They answered 40 clinical vignette-based multiple-choice questions during fMRI scanning. We compared the imaging data for 20 problem-solving questions (reasoning task) and 20 recall questions (recall task). Compared to the recall task, the reasoning task resulted in significantly greater activation in nine brain regions, including the dorsolateral prefrontal cortex and inferior parietal cortex, which are known to be associated with executive function and deductive reasoning. During the recall task, significant activation was observed in the brain regions that are related to memory and emotions, including the amygdala and ventromedial prefrontal cortex. Our results support that medical students mainly solve clinical questions with deductive reasoning involving prior knowledge structures and executive functions. The problem-solving questions induced the students to utilize higher cognitive functions compared with the recall questions. Interestingly, the results suggested that the students experienced some emotional distress while they were solving the recall questions. In addition, these results suggest that fMRI is a promising research tool for investigating students' cognitive processes.

  5. Coordinate based meta-analysis of functional neuroimaging data; false discovery control and diagnostics.

    PubMed

    Tench, Christopher R; Tanasescu, Radu; Auer, Dorothee P; Constantinescu, Cris S

    2013-01-01

    Coordinate based meta-analysis (CBMA) is widely used to find regions of consistent activation across fMRI studies that have been selected for their functional relevance to a given hypothesis. Only reported coordinates (foci), and a model of their spatial uncertainty, are used in the analysis. Results are clusters of foci where multiple studies have reported in the same spatial region, indicating functional relevance. There are several published methods that perform the analysis in a voxel-wise manner, resulting in around 10(5) statistical tests, and considerable emphasis placed on controlling the risk of type 1 statistical error. Here we address this issue by dramatically reducing the number of tests, and by introducing a new false discovery rate control: the false cluster discovery rate (FCDR). FCDR is particularly interpretable and relevant to the results of CBMA, controlling the type 1 error by limiting the proportion of clusters that are expected under the null hypothesis. We also introduce a data diagnostic scheme to help ensure quality of the analysis, and demonstrate its use in the example studies. We show that we control the false clusters better than the widely used ALE method by performing numerical experiments, and that our clustering scheme results in more complete reporting of structures relevant to the functional task.

  6. Synchronous multiscale neuroimaging environment for critically sampled physiological analysis of brain function: hepta-scan concept.

    PubMed

    Korhonen, Vesa; Hiltunen, Tuija; Myllylä, Teemu; Wang, Xindi; Kantola, Jussi; Nikkinen, Juha; Zang, Yu-Feng; LeVan, Pierre; Kiviniemi, Vesa

    2014-11-01

    Functional connectivity of the resting-state networks of the brain is thought to be mediated by very-low-frequency fluctuations (VLFFs <0.1 Hz) in neuronal activity. However, vasomotor waves and cardiorespiratory pulsations influence indirect measures of brain function, such as the functional magnetic resonance imaging blood-oxygen-level-dependent (BOLD) signal. How strongly physiological oscillations correlate with spontaneous BOLD signals is not known, partially due to differences in the data-sampling rates of different methods. Recent ultrafast inverse imaging sequences, including magnetic resonance encephalography (MREG), enable critical sampling of these signals. In this study, we describe a multimodal concept, referred to as Hepta-scan, which incorporates synchronous MREG with scalp electroencephalography, near-infrared spectroscopy, noninvasive blood pressure, and anesthesia monitoring. Our preliminary results support the idea that, in the absence of aliased cardiorespiratory signals, VLFFs in the BOLD signal are affected by vasomotor and electrophysiological sources. Further, MREG signals showed a high correlation coefficient between the ventromedial default mode network (DMNvmpf) and electrophysiological signals, especially in the VLF range. Also, oxy- and deoxyhemoglobin and vasomotor waves were found to correlate with DMNvmpf. Intriguingly, usage of shorter time windows in these correlation measurements produced significantly (p<0.05) higher positive and negative correlation coefficients, suggesting temporal nonstationary behavior between the measurements. Focus on the VLF range strongly increased correlation strength.

  7. Cortical morphology as a shared neurobiological substrate of attention-deficit/hyperactivity symptoms and executive functioning: a population-based pediatric neuroimaging study

    PubMed Central

    Mous, Sabine E.; White, Tonya; Muetzel, Ryan L.; El Marroun, Hanan; Rijlaarsdam, Jolien; Polderman, Tinca J.C.; Jaddoe, Vincent W.; Verhulst, Frank C.; Posthuma, Danielle; Tiemeier, Henning

    2017-01-01

    Background Attention-deficit/hyperactivity symptoms have repeatedly been associated with poor cognitive functioning. Genetic studies have demonstrated a shared etiology of attention-deficit/hyperactivity disorder (ADHD) and cognitive ability, suggesting a common underlying neurobiology of ADHD and cognition. Further, neuroimaging studies suggest that altered cortical development is related to ADHD. In a large population-based sample we investigated whether cortical morphology, as a potential neurobiological substrate, underlies the association between attention-deficit/hyperactivity symptoms and cognitive problems. Methods The sample consisted of school-aged children with data on attention-deficit/hyperactivity symptoms, cognitive functioning and structural imaging. First, we investigated the association between attention-deficit/hyperactivity symptoms and different domains of cognition. Next, we identified cortical correlates of attention-deficit/hyperactivity symptoms and related cognitive domains. Finally, we studied the role of cortical thickness and gyrification in the behaviour–cognition associations. Results We included 776 children in our analyses. We found that attention-deficit/hyperactivity symptoms were associated specifically with problems in attention and executive functioning (EF; b = −0.041, 95% confidence interval [CI] −0.07 to −0.01, p = 0.004). Cortical thickness and gyrification were associated with both attention-deficit/hyperactivity symptoms and EF in brain regions that have been previously implicated in ADHD. This partly explained the association between attention-deficit/hyperactivity symptoms and EF (bindirect = −0.008, bias-corrected 95% CI −0.018 to −0.001). Limitations The nature of our study did not allow us to draw inferences regarding temporal associations; longitudinal studies are needed for clarification. Conclusion In a large, population-based sample of children, we identified a shared cortical morphology underlying

  8. The Developmental Trajectory of Brain-Scalp Distance from Birth through Childhood: Implications for Functional Neuroimaging

    PubMed Central

    Beauchamp, Michael S.; Beurlot, Michelle R.; Fava, Eswen; Nath, Audrey R.; Parikh, Nehal A.; Saad, Ziad S.; Bortfeld, Heather; Oghalai, John S.

    2011-01-01

    Measurements of human brain function in children are of increasing interest in cognitive neuroscience. Many techniques for brain mapping used in children, including functional near-infrared spectroscopy (fNIRS), electroencephalography (EEG), magnetoencephalography (MEG) and transcranial magnetic stimulation (TMS), use probes placed on or near the scalp. The distance between the scalp and the brain is a key variable for these techniques because optical, electrical and magnetic signals are attenuated by distance. However, little is known about how scalp-brain distance differs between different cortical regions in children or how it changes with development. We investigated scalp-brain distance in 71 children, from newborn to age 12 years, using structural T1-weighted MRI scans of the whole head. Three-dimensional reconstructions were created from the scalp surface to allow for accurate calculation of brain-scalp distance. Nine brain landmarks in different cortical regions were manually selected in each subject based on the published fNIRS literature. Significant effects were found for age, cortical region and hemisphere. Brain-scalp distances were lowest in young children, and increased with age to up to double the newborn distance. There were also dramatic differences between brain regions, with up to 50% differences between landmarks. In frontal and temporal regions, scalp-brain distances were significantly greater in the right hemisphere than in the left hemisphere. The largest contributors to developmental changes in brain-scalp distance were increases in the corticospinal fluid (CSF) and inner table of the cranium. These results have important implications for functional imaging studies of children: age and brain-region related differences in fNIRS signals could be due to the confounding factor of brain-scalp distance and not true differences in brain activity. PMID:21957470

  9. A composite score for executive functioning, validated in Alzheimer's Disease Neuroimaging Initiative (ADNI) participants with baseline mild cognitive impairment.

    PubMed

    Gibbons, Laura E; Carle, Adam C; Mackin, R Scott; Harvey, Danielle; Mukherjee, Shubhabrata; Insel, Philip; Curtis, S McKay; Mungas, Dan; Crane, Paul K

    2012-12-01

    The Alzheimer's Disease Neuroimaging Initiative (ADNI) measures abilities broadly related to executive function (EF), including WAIS-R Digit Symbol Substitution, Digit Span Backwards, Trails A and B, Category Fluency, and Clock Drawing. This study investigates whether a composite executive function measure based on these multiple indicators has better psychometric characteristics than the widely used individual components. We applied item response theory methods to 800 ADNI participants to derive an EF composite score (ADNI-EF) from the above measures. We then compared ADNI-EF with component measures in 390 longitudinally-followed participants with mild cognitive impairment (MCI) with respect to: (1) Ability to detect change over time; (2) Ability to predict conversion to dementia; (3) Strength of cross-sectional association with MRI-derived measures of structures involved in frontal systems, and (4) Strength of baseline association with cerebrospinal fluid (CSF) levels of amyloid β₁₋₄₂, total tau, and phosphorylated tau(181P). ADNI-EF showed the greatest change over time, followed closely by Category Fluency. ADNI-EF needed a 40 % smaller sample size to detect change. ADNI-EF was the strongest predictor of AD conversion. ADNI-EF was the only measure significantly associated with all the MRI regions, though other measures were more strongly associated in a few of the regions. ADNI-EF was associated with all the CSF measures. ADNI-EF appears to be a useful composite measure of EF in MCI, as good as or better than any of its composite parts. This study demonstrates an approach to developing a psychometrically sophisticated composite score from commonly-used tests.

  10. Challenges and Pitfalls Associated with Diagnostic and Prognostic Applications of Functional Neuroimaging in Disorders of Consciousness

    PubMed Central

    Bodien, Yelena G.; Giacino, Joseph T.

    2016-01-01

    The diagnostic assessment of patients with disorder of consciousness is currently based on clinical testing at the bedside and prone to a high error rate in the assessment of the degree of conscious awareness. Investigation of more objective assessment strategies, such as the use of functional magnetic resonance imaging (fMRI) to detect conscious awareness, are becoming increasingly popular in the research community. However, inherent challenges to the use of fMRI threaten its validity as a diagnostic tool and will need to be resolved prior to its integration into the clinical setting. These challenges, which range from the heterogeneity of the patient sample to factors influencing data acquisition and biases in interpretation strategies, are discussed below. Recommendations aimed at mitigating some of the limitations are provided. PMID:27347262

  11. Behavioral and neuroimaging evidence for impaired executive function in "cognitively normal" older HIV-infected adults.

    PubMed

    Jiang, Xiong; Barasky, Rebecca; Olsen, Halli; Riesenhuber, Maximilian; Magnus, Manya

    2016-01-01

    The increased prevalence of HIV among adults >50 years underscores the importance of improving our understanding of mechanisms causing HIV-associated neurocognitive disorders (HAND). Identifying novel and noninvasive diagnostic predictors of HAND prior to clinical manifestation is critical to ultimately identifying means of preventing progression to symptomatic HAND. Here, using a task-switching paradigm, in which subjects were cued (unpredictably) to perform a face-gender or a word-semantic task on superimposed face and word images, we examined the behavioral and neural profile of impaired cognitive control in older HIV + adults (N = 14, 9 HIV+). Functional magnetic resonance imaging (fMRI) and behavioral data were acquired while subjects were performing the face-gender or word-semantic task. We found that, despite comparable performance in standard neuropsychology tests that are designed to probe executive deficits, HIV-infected participants were significantly slower than uninfected controls in adapting to change in task demand, and the behavioral impairments can be quantitatively related to difference in fMRI signal at the dorsal anterior cingulate cortex (ACC). Due to the limited sample size of this hypothesis-generating study, we should take caution with these findings and future studies with a large and better matched sample size are needed. However, these rather novel findings in this study have a few important implications: first, the prevalence of cognitive impairments in HIV+ older adults might be even higher than previously proposed; second, ACC (in particularly its dorsal region) might be one of the key regions underlying cognitive impairments (in particularly executive functions) in HIV; and third, it might be beneficial to adopt paradigms developed and validated in cognitive neuroscience to study HAND, as these techniques might be more sensitive to some aspects of HIV-associated neurocognitive impairments than standard neuropsychology tests.

  12. Development of optical neuroimaging to detect drug-induced brain functional changes in vivo

    NASA Astrophysics Data System (ADS)

    Du, Congwu; Pan, Yingtian

    2014-03-01

    Deficits in prefrontal function play a crucial role in compulsive cocaine use, which is a hallmark of addiction. Dysfunction of the prefrontal cortex might result from effects of cocaine on neurons as well as from disruption of cerebral blood vessels. However, the mechanisms underlying cocaine's neurotoxic effects are not fully understood, partially due to technical limitations of current imaging techniques (e.g., PET, fMRI) to differentiate vascular from neuronal effects at sufficiently high temporal and spatial resolutions. We have recently developed a multimodal imaging platform which can simultaneously characterize the changes in cerebrovascular hemodynamics, hemoglobin oxygenation and intracellular calcium fluorescence for monitoring the effects of cocaine on the brain. Such a multimodality imaging technique (OFI) provides several uniquely important merits, including: 1) a large field-of-view, 2) high spatiotemporal resolutions, 3) quantitative 3D imaging of the cerebral blood flow (CBF) networks, 4) label-free imaging of hemodynamic changes, 5) separation of vascular compartments (e.g., arterial and venous vessels) and monitoring of cortical brain metabolic changes, 6) discrimination of cellular (neuronal) from vascular responses. These imaging features have been further advanced in combination with microprobes to form micro-OFI that allows quantification of drug effects on subcortical brain. In addition, our ultrahigh-resolution ODT (μODT) enables 3D microangiography and quantitative imaging of capillary CBF networks. These optical strategies have been used to investigate the effects of cocaine on brain physiology to facilitate the studies of brain functional changes induced by addictive substance to provide new insights into neurobiological effects of the drug on the brain.

  13. Abnormalities of Dorsolateral Prefrontal Function in Women With Premenstrual Dysphoric Disorder: A Multimodal Neuroimaging Study

    PubMed Central

    Baller, Erica B.; Wei, Shau-Ming; Kohn, Philip D.; Rubinow, David R.; Alarcón, Gabriela; Schmidt, Peter J.; Berman, Karen F.

    2014-01-01

    Objective To investigate the neural substrate of premenstrual dysphoric disorder (PMDD), the authors used [15O]H2O positron emission tomography (PET) regional cerebral blood flow (rCBF) and blood-oxygen-level-dependent (BOLD) functional MRI (fMRI) signal measurements during working memory in conjunction with a 6-month hormone manipulation protocol. Method PET and fMRI scans were obtained from women with prospectively confirmed PMDD and asymptomatic comparison subjects while they completed the n-back task during three hormone conditions: ovarian suppression induced by the gonadotropin-releasing hormone agonist leuprolide acetate, leuprolide plus estradiol, and leuprolide plus progesterone. Fifteen patients and 15 matched comparison subjects underwent PET imaging. Fourteen patients and 14 comparison subjects underwent fMRI. For each hormone condition, rCBF was measured with [15O]H2O PET, and BOLD signal was measured with fMRI, both during an n-back working memory paradigm. Global Assessment of Functioning Scale (GAF) scores and clinical characteristics were obtained for each patient before hormone manipulation, and symptoms were measured before and during the protocol. Results In both the PET and fMRI studies, a main effect of diagnosis was observed, with PMDD patients showing greater prefrontal activation than comparison subjects. In the patient group, the degree to which dorsolateral prefrontal cortex activation was abnormally increased correlated with several dimensions of disease: disability as indicated by GAF scores, age at symptom onset, duration of PMDD, and differences in pre- and postmenses PMDD symptoms. Conclusions Abnormal working memory activation in PMDD, specifically in the dorsolateral prefrontal cortex, is related to PMDD severity, symptoms, age at onset, and disease burden. These results support the clinical relevance of the findings and the proposal that dorsolateral prefrontal cortex dysfunction represents a substrate of risk for PMDD. The

  14. Functional neuroimaging of visuospatial working memory tasks enables accurate detection of attention deficit and hyperactivity disorder

    PubMed Central

    Hammer, Rubi; Cooke, Gillian E.; Stein, Mark A.; Booth, James R.

    2015-01-01

    Finding neurobiological markers for neurodevelopmental disorders, such as attention deficit and hyperactivity disorder (ADHD), is a major objective of clinicians and neuroscientists. We examined if functional Magnetic Resonance Imaging (fMRI) data from a few distinct visuospatial working memory (VSWM) tasks enables accurately detecting cases with ADHD. We tested 20 boys with ADHD combined type and 20 typically developed (TD) boys in four VSWM tasks that differed in feedback availability (feedback, no-feedback) and reward size (large, small). We used a multimodal analysis based on brain activity in 16 regions of interest, significantly activated or deactivated in the four VSWM tasks (based on the entire participants' sample). Dimensionality of the data was reduced into 10 principal components that were used as the input variables to a logistic regression classifier. fMRI data from the four VSWM tasks enabled a classification accuracy of 92.5%, with high predicted ADHD probability values for most clinical cases, and low predicted ADHD probabilities for most TDs. This accuracy level was higher than those achieved by using the fMRI data of any single task, or the respective behavioral data. This indicates that task-based fMRI data acquired while participants perform a few distinct VSWM tasks enables improved detection of clinical cases. PMID:26509111

  15. Functional neuroimaging of speech perception during a pivotal period in language acquisition.

    PubMed

    Redcay, Elizabeth; Haist, Frank; Courchesne, Eric

    2008-03-01

    A pivotal period in the development of language occurs in the second year of life, when language comprehension undergoes rapid acceleration. However, the brain bases of these advances remain speculative as there is currently no functional magnetic resonance imaging (fMRI) data from healthy, typically developing toddlers at this age. We investigated the neural basis of speech comprehension in this critical age period by measuring fMRI activity during passive speech comprehension in 10 toddlers (mean +/- SD; 21 +/- 4 mo) and 10 3-year-old children (39 +/- 3 mo) during natural sleep. During sleep, the children were presented passages of forward and backward speech in 20-second blocks separated by 20-second periods of no sound presentation. Toddlers produced significantly greater activation in frontal, occipital, and cerebellar regions than 3-year-old children in response to forward speech. Our results suggest that rapid language acquisition during the second year of life may require the utilization of frontal, cerebellar, and occipital regions in addition to classical superior temporal language areas. These findings are consistent with the interactive specialization hypothesis, which proposes that cognitive abilities develop from the interaction of brain regions that include and extend beyond those used in the adult brain.

  16. Detailed exploration of face-related processing in congenital prosopagnosia: 2. Functional neuroimaging findings.

    PubMed

    Avidan, Galia; Hasson, Uri; Malach, Rafael; Behrmann, Marlene

    2005-07-01

    Specific regions of the human occipito-temporal cortex are consistently activated in functional imaging studies of face processing. To understand the contribution of these regions to face processing, we examined the pattern of fMRI activation in four congenital prosopagnosic (CP) individuals who are markedly impaired at face processing despite normal vision and intelligence, and with no evidence of brain damage. These individuals evinced a normal pattern of fMRI activation in the fusiform gyrus (FFA) and in other ventral occipito-temporal areas, in response to faces, buildings, and other objects, shown both as line drawings in detection and discrimination tasks and under more naturalistic testing conditions when no task was required. CP individuals also showed normal adaptation levels in a block-design adaptation experiment and, like control subjects, exhibited evidence of global face representation in the FFA. The absence of a BOLD-behavioral correlation (profound behavioral deficit, normal face-related activation in the ventral occipito-temporal cortex) challenges existing accounts of face representation, and suggests that activation in these cortical regions per se is not sufficient to ensure intact face processing.

  17. Identification of famous faces and buildings: a functional neuroimaging study of semantically unique items.

    PubMed

    Gorno-Tempini, M L; Price, C J

    2001-10-01

    Several functional imaging experiments have clearly established that the fusiform gyri are preferentially responsive to faces, whereas the parahippocampal/lingual gyri are more responsive to buildings. Other studies have demonstrated that famous faces additionally activate the anterior temporal cortex relative to unfamiliar faces, animals, tools, body parts and maps. One explanation for this apparent specialization for known people could be that famous faces are 'semantically unique items'. In other words, they carry unique semantic associations that are not shared by other perceptually similar category members. If this hypothesis is correct, the anterior temporal cortex should also respond to other semantically unique items, such as famous buildings. In this PET study, we investigated the effect of fame (famous relative to non-famous) on activation elicited by famous and non-famous faces and buildings during a same-different matching task. We found that, when the task was held constant, category-specific activations in the fusiform and parahippocampal/lingual areas were not modulated by fame. In contrast, in the left anterior middle temporal gyrus there was an effect of fame that was common to faces and buildings. These results suggest that the identification of famous faces and buildings involves category-specific perceptual processing in the fusiform and parahippocampal/lingual regions, respectively, and shared analysis of unique semantic attributes in the left anterior temporal cortex.

  18. Aberrant frontoparietal function during recognition memory in schizophrenia: a multimodal neuroimaging investigation.

    PubMed

    Weiss, Anthony P; Ellis, Cameron B; Roffman, Joshua L; Stufflebeam, Steven; Hamalainen, Matti S; Duff, Margaret; Goff, Donald C; Schacter, Daniel L

    2009-09-09

    Prefrontal-parietal networks are essential to many cognitive processes, including the ability to differentiate new from previously presented items. As patients with schizophrenia exhibit structural abnormalities in these areas along with well documented decrements in recognition memory, we hypothesized that these patients would demonstrate memory-related abnormalities in prefrontal and parietal physiology as measured by both functional magnetic resonance imaging and magnetoencephalography (MEG). Medicated outpatients with schizophrenia (n = 18) and age-matched healthy control subjects (n = 18) performed an old-new recognition memory task while physiological data were obtained. Whereas controls exhibited strong, bilateral activation of prefrontal and posterior parietal regions during successful identification of old versus new items, patients exhibited greatly attenuated activation of the right prefrontal and parietal cortices. However, within the patient group, there was strong correlation between memory performance and activation of these right-sided regions as well as a tight correlation between old-new effect-related activations in frontal and parietal regions, a pattern not seen in control subjects. Using MEG, control subjects-but not patients-exhibited a sequential pattern of old > new activity in the left posterior parietal cortex and then right prefrontal cortex; however, patients uniquely exhibited old > new activity in right temporal cortex. Collectively, these findings point to markedly different distributions of regional specialization necessary to complete the old-new item recognition task in patients versus controls. Inefficient utilization of prefrontal-parietal networks, with compensatory activation in temporal regions, may thus contribute to deficient old-new item recognition in schizophrenia.

  19. Aberrant frontoparietal function during recognition memory in schizophrenia: a multimodal neuroimaging investigation

    PubMed Central

    Weiss, Anthony P.; Ellis, Cameron B.; Roffman, Joshua L.; Stufflebeam, Steven; Hamalainen, Matti S.; Duff, Margaret; Goff, Donald C.; Schacter, Daniel L.

    2009-01-01

    Prefrontal-parietal networks are essential to many cognitive processes, including the ability to differentiate new from previously presented items. As patients with schizophrenia exhibit structural abnormalities in these areas along with well-documented decrements in recognition memory, we hypothesized that these patients would demonstrate memory-related abnormalities in prefrontal and parietal physiology as measured by both functional magnetic resonance imaging (fMRI) and magnetoelectroencephalography (MEG). Medicated outpatients with schizophrenia (n=18) and age-matched healthy control subjects (n=18) performed an old-new recognition memory task while physiological data were obtained. Whereas controls exhibited strong, bilateral activation of prefrontal and posterior parietal regions during successful identification of old versus new items, patients exhibited greatly attenuated activation of the right prefrontal and parietal cortices. However, within the patient group there was strong correlation between memory performance and activation of these right-sided regions as well as a tight correlation between old-new effect-related activations in frontal and parietal regions; a pattern not seen in control subjects. Using MEG, control subjects - but not patients - exhibited a sequential pattern of old > new activity in the left posterior parietal cortex and then right prefrontal cortex; however, patients uniquely exhibited old > new activity in right temporal cortex. Collectively, these findings point to markedly different distributions of regional specialization necessary to complete the old-new item recognition task in patients versus controls. Inefficient utilization of prefrontal-parietal networks, with compensatory activation in temporal regions, may thus contribute to deficient old-new item recognition in schizophrenia. PMID:19741141

  20. Functional Neuroimaging Correlates of Burnout among Internal Medicine Residents and Faculty Members

    PubMed Central

    Durning, Steven J.; Costanzo, Michelle; Artino, Anthony R.; Dyrbye, Liselotte N.; Beckman, Thomas J.; Schuwirth, Lambert; Holmboe, Eric; Roy, Michael J.; Wittich, Christopher M.; Lipner, Rebecca S.; van der Vleuten, Cees

    2013-01-01

    Burnout is prevalent in residency training and practice and is linked to medical error and suboptimal patient care. However, little is known about how burnout affects clinical reasoning, which is essential to safe and effective care. The aim of this study was to examine how burnout modulates brain activity during clinical reasoning in physicians. Using functional Magnetic Resonance Imaging (fMRI), brain activity was assessed in internal medicine residents (n = 10) and board-certified internists (faculty, n = 17) from the Uniformed Services University (USUHS) while they answered and reflected upon United States Medical Licensing Examination and American Board of Internal Medicine multiple-choice questions. Participants also completed a validated two-item burnout scale, which includes an item assessing emotional exhaustion and an item assessing depersonalization. Whole brain covariate analysis was used to examine blood-oxygen-level-dependent (BOLD) signal during answering and reflecting upon clinical problems with respect to burnout scores. Higher depersonalization scores were associated with less BOLD signal in the right dorsolateral prefrontal cortex and middle frontal gyrus during reflecting on clinical problems and less BOLD signal in the bilateral precuneus while answering clinical problems in residents. Higher emotional exhaustion scores were associated with more right posterior cingulate cortex and middle frontal gyrus BOLD signal in residents. Examination of faculty revealed no significant influence of burnout on brain activity. Residents appear to be more susceptible to burnout effects on clinical reasoning, which may indicate that residents may need both cognitive and emotional support to improve quality of life and to optimize performance and learning. These results inform our understanding of mental stress, cognitive control as well as cognitive load theory. PMID:24133462

  1. Semantic interference and its control: A functional neuroimaging and connectivity study.

    PubMed

    Canini, Matteo; Della Rosa, Pasquale Anthony; Catricalà, Eleonora; Strijkers, Kristof; Branzi, Francesca Martina; Costa, Albert; Abutalebi, Jubin

    2016-11-01

    During picture naming, the ease with which humans generate words is dependent upon the context in which they are named. For instances, naming previously presented items results in facilitation. Instead, naming a picture semantically related to previous items displays persistent interference effects (i.e., cumulative semantic interference, CSI). The neural correlates of CSI are still unclear and it is a matter of debate whether semantic control, or cognitive control more in general, is necessary for the resolution of CSI. We carried out an event-related fMRI experiment to assess the neural underpinnings of the CSI effect and the involvement and nature of semantic control. Both left inferior frontal gyrus (LIFG) and the left caudate nucleus (LCN) showed a linear increase of BOLD response positively associated with the consecutive number of presentations of semantically related pictures independently of task-load. The generalized psychophysiological interaction analysis showed that LIFG demonstrated a quantitative neural connectivity difference with the left supramarginal and angular gyri for increases of task-load and with the fusiform gyri for linear CSI increases. Furthermore, seed-to-voxel functional connectivity showed that LIFG activity coupled with different regions involved in cognitive control and lexicosemantic processing when semantic interference was elicited to a minimum or maximum degree. Our results are consistent with the lexical-competitive nature of the CSI effect, and we provide novel evidence that semantic control lies upon a more general cognitive control network (i.e., LIFG and LCN) responsible for resolving interference between competing semantically related items through connectivity with different brain areas in order to guarantee the correct response. Hum Brain Mapp 37:4179-4196, 2016. © 2016 Wiley Periodicals, Inc.

  2. Neuroimaging findings in primary insomnia.

    PubMed

    O'Byrne, J N; Berman Rosa, M; Gouin, J-P; Dang-Vu, T T

    2014-10-01

    State-of-the-art neuroimaging techniques have accelerated progress in the study and understanding of sleep in humans. Neuroimaging studies in primary insomnia remain relatively few, considering the important prevalence of this disorder in the general population. This review examines the contribution of functional and structural neuroimaging to our current understanding of primary insomnia. Functional studies during sleep provided support for the hyperarousal theory of insomnia. Functional neuroimaging also revealed abnormalities in cognitive and emotional processing in primary insomnia. Results from structural studies suggest neuroanatomical alterations in primary insomnia, mostly in the hippocampus, anterior cingulate cortex and orbitofrontal cortex. However, these results are not well replicated across studies. A few magnetic resonance spectroscopy studies revealed abnormalities in neurotransmitter concentrations and bioenergetics in primary insomnia. The inconsistencies among neuroimaging findings on insomnia are likely due to clinical heterogeneity, differences in imaging and overall diversity of techniques and designs employed. Larger samples, replication, as well as innovative methodologies are necessary for the progression of this perplexing, yet promising area of research.

  3. Neuroimaging Endophenotypes in Autism Spectrum Disorder

    PubMed Central

    Mahajan, Rajneesh; Mostofsky, Stewart H.

    2015-01-01

    Autism spectrum disorder (ASD) is a neurodevelopmental disorder that has a strong genetic basis, and is heterogeneous in its etiopathogenesis and clinical presentation. Neuroimaging studies, in concert with neuropathological and clinical research, have been instrumental in delineating trajectories of development in children with ASD. Structural neuroimaging has revealed ASD to be a disorder with general and regional brain enlargement, especially in the frontotemporal cortices, while functional neuroimaging studies have highlighted diminished connectivity, especially between frontal-posterior regions. The diverse and specific neuroimaging findings may represent potential neuroendophenotypes, and may offer opportunities to further understand the etiopathogenesis of ASD, predict treatment response and lead to the development of new therapies. PMID:26234701

  4. Neuroimaging of Cognition

    PubMed Central

    Dolan, R.J.

    2009-01-01

    Neuroimaging, particularly that based upon functional magnetic resonance (fMRI), has become a dominant tool in cognitive neuroscience. This review provides a personal and selective perspective on its past, present, and future. Two trends currently characterize the field that broadly reflect a pursuit of “where”- and “how”-type questions. The latter addresses basic mechanisms related to the expression of task-induced neural activity and is likely to be an increasingly important theme in the future. This trend entails an enhanced symbiosis among investigators pursuing similar questions in fields such as computational and theoretical neuroscience as well as through the detailed analysis of microcircuitry. PMID:18995825

  5. PRoNTo: pattern recognition for neuroimaging toolbox.

    PubMed

    Schrouff, J; Rosa, M J; Rondina, J M; Marquand, A F; Chu, C; Ashburner, J; Phillips, C; Richiardi, J; Mourão-Miranda, J

    2013-07-01

    In the past years, mass univariate statistical analyses of neuroimaging data have been complemented by the use of multivariate pattern analyses, especially based on machine learning models. While these allow an increased sensitivity for the detection of spatially distributed effects compared to univariate techniques, they lack an established and accessible software framework. The goal of this work was to build a toolbox comprising all the necessary functionalities for multivariate analyses of neuroimaging data, based on machine learning models. The "Pattern Recognition for Neuroimaging Toolbox" (PRoNTo) is open-source, cross-platform, MATLAB-based and SPM compatible, therefore being suitable for both cognitive and clinical neuroscience research. In addition, it is designed to facilitate novel contributions from developers, aiming to improve the interaction between the neuroimaging and machine learning communities. Here, we introduce PRoNTo by presenting examples of possible research questions that can be addressed with the machine learning framework implemented in PRoNTo, and cannot be easily investigated with mass univariate statistical analysis.

  6. Neuroimaging of the Functional and Structural Networks Underlying Visuospatial vs. Linguistic Reasoning in High-Functioning Autism

    ERIC Educational Resources Information Center

    Sahyoun, Cherif P.; Belliveau, John W.; Soulieres, Isabelle; Schwartz, Shira; Mody, Maria

    2010-01-01

    High-functioning individuals with autism have been found to favor visuospatial processing in the face of typically poor language abilities. We aimed to examine the neurobiological basis of this difference using functional magnetic resonance imaging and diffusion tensor imaging. We compared 12 children with high functioning autism (HFA) to 12 age-…

  7. Treatment of Pica through Multiple Analyses of Its Reinforcing Functions.

    ERIC Educational Resources Information Center

    Piazza, Cathleen C.; Fisher, Wayne W.; Hanley, Gregory P.; LeBlanc, Linda A.; Worsdell, April S.; And Others

    1998-01-01

    A study conducted functional analyses of the pica of three young children. The pica of one participant was maintained by automatic reinforcement; that of the other two was multiply-controlled by social and automatic reinforcement. Preference and treatment analyses were used to address the automatic function of the pica. (Author/CR)

  8. Training Residential Staff to Conduct Trial-Based Functional Analyses

    ERIC Educational Resources Information Center

    Lambert, Joseph M.; Bloom, Sarah E.; Kunnavatana, S. Shanun; Collins, Shawnee D.; Clay, Casey J.

    2013-01-01

    We taught 6 supervisors of a residential service provider for adults with developmental disabilities to train 9 house managers to conduct trial-based functional analyses. Effects of the training were evaluated with a nonconcurrent multiple baseline. Results suggest that house managers can be trained to conduct trial-based functional analyses with…

  9. Neuroimaging of Cognitive Load in Instructional Multimedia

    ERIC Educational Resources Information Center

    Whelan, Robert R.

    2007-01-01

    This paper reviews research literature on cognitive load measurement in learning and neuroimaging, and describes a mapping between the main elements of cognitive load theory and findings in functional neuroanatomy. It is argued that these findings may lead to the improved measurement of cognitive load using neuroimaging. The paper describes how…

  10. Development of PowerMap: a software package for statistical power calculation in neuroimaging studies.

    PubMed

    Joyce, Karen E; Hayasaka, Satoru

    2012-10-01

    Although there are a number of statistical software tools for voxel-based massively univariate analysis of neuroimaging data, such as fMRI (functional MRI), PET (positron emission tomography), and VBM (voxel-based morphometry), very few software tools exist for power and sample size calculation for neuroimaging studies. Unlike typical biomedical studies, outcomes from neuroimaging studies are 3D images of correlated voxels, requiring a correction for massive multiple comparisons. Thus, a specialized power calculation tool is needed for planning neuroimaging studies. To facilitate this process, we developed a software tool specifically designed for neuroimaging data. The software tool, called PowerMap, implements theoretical power calculation algorithms based on non-central random field theory. It can also calculate power for statistical analyses with FDR (false discovery rate) corrections. This GUI (graphical user interface)-based tool enables neuroimaging researchers without advanced knowledge in imaging statistics to calculate power and sample size in the form of 3D images. In this paper, we provide an overview of the statistical framework behind the PowerMap tool. Three worked examples are also provided, a regression analysis, an ANOVA (analysis of variance), and a two-sample T-test, in order to demonstrate the study planning process with PowerMap. We envision that PowerMap will be a great aide for future neuroimaging research.

  11. Neuroimaging evaluation in refractory epilepsy

    PubMed Central

    Granados, Ana M; Orejuela, Juan F

    2015-01-01

    Purpose To describe the application of neuroimaging analysis, compared to neuropsychological tests and video-electroencephalogram, for the evaluation of refractory epilepsy in a reference centre in Cali, Colombia. Methods Between March 2013 and November 2014, 29 patients, 19 men and 10 women, aged 9–65 years and with refractory epilepsy, were assessed by structural and functional magnetic resonance imaging while performing tasks related to language, verbal and non-verbal memory. Also, volumetric evaluation was performed. A 1.5 Tesla magnetic resonance imaging scanner was used in all cases. Results Neuroimaging evaluation identified 13 patients with mesial temporal sclerosis. The remaining patients were classified as: 10 patients with neoplastic masses, two patients with cortical atrophy, two patients with scarring lesions and two patients with non-structural aetiology. Among patients with mesial temporal sclerosis, comparison between techniques for lateralising the epileptogenic foci was made; the κ index between functional magnetic resonance imaging and hippocampi volumetry was κ = 1.00, agreement between neuroimaging and video-electroencephalogram was good (κ = 0.78) and comparison with a neuropsychological test was mild (κ = 0.24). Conclusions Neuroimaging studies allow the assessment of functional and structural damage related to epileptogenic lesions and foci, and are helpful to select surgical treatment, conduct intraoperative neuronavigation techniques, predict surgical deficits and evaluate patient recovery. PMID:26427897

  12. Recent Trends in Conducting School-Based Experimental Functional Analyses

    ERIC Educational Resources Information Center

    Carter, Stacy L.

    2009-01-01

    Demonstrations of school-based experimental functional analyses have received limited attention within the literature. School settings present unique practical and ethical concerns related to the implementation of experimental analyses which were originally developed within clinical settings. Recent examples have made definite contributions toward…

  13. Progressing from Initially Ambiguous Functional Analyses: Three Case Examples

    ERIC Educational Resources Information Center

    Tiger, Jeffrey H.; Fisher, Wayne W.; Toussaint, Karen A.; Kodak, Tiffany

    2009-01-01

    Most often functional analyses are initiated using a standard set of test conditions, similar to those described by Iwata, Dorsey, Slifer, Bauman, and Richman [Iwata, B. A., Dorsey, M. F., Slifer, K. J., Bauman, K. E., & Richman, G. S. (1994). "Toward a functional analysis of self-injury." "Journal of Applied Behavior Analysis, 27", 197-209…

  14. Disorder of Executive Function of the Brain after Head Injury and Mild Traumatic Brain Injury - Neuroimaging and Diagnostic Criteria for Implementation of Administrative Support in Japan.

    PubMed

    Shinoda, Jun; Asano, Yoshitaka

    2017-04-06

    The diagnotic criteria for disorder of the executive function of the brain (DEFB) as a syndrome of sequela were administratively established (ad-DEFB) in Japan in 2006 to support disabled patients whose impairment, limited to cognition (memory, attention, execution, and behavior), emerges after organic brain injuries regardless of physical deficits. However, some patients suffering from traumatic brain injury (TBI) have been excluded from receiving medico-social services. In particular, this tendency is more prominent in patients with mild TBI because no lesions are apparent on conventional computed tomography (CT) or magnetic resonance imaging (MRI) in the chronic phase. Recent development of new MRI neuroimaging modalities and positron emission tomography (PET) imaging makes it possible to detect regions of minute organic lesions and metabolic dysfunction in the brain where organic lesions may be absent or cannot be detected on conventional CT or MRI. In this review, we discuss diagnostic criteria for mild TBI and ad-DEFB, the relationship between the two disorders, characteristic neuroimaging [(MRI and 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET)] of diffuse brain injury including cerebral concussion, which is the principal cause of mild TBI, and suggested pathological mechanisms of ad-DEFB in DBI.

  15. Workflow-based approaches to neuroimaging analysis.

    PubMed

    Fissell, Kate

    2007-01-01

    Analysis of functional and structural magnetic resonance imaging (MRI) brain images requires a complex sequence of data processing steps to proceed from raw image data to the final statistical tests. Neuroimaging researchers have begun to apply workflow-based computing techniques to automate data analysis tasks. This chapter discusses eight major components of workflow management systems (WFMSs): the workflow description language, editor, task modules, data access, verification, client, engine, and provenance, and their implementation in the Fiswidgets neuroimaging workflow system. Neuroinformatics challenges involved in applying workflow techniques in the domain of neuroimaging are discussed.

  16. Stress regulation in the central nervous system: evidence from structural and functional neuroimaging studies in human populations - 2008 Curt Richter Award Winner.

    PubMed

    Pruessner, Jens C; Dedovic, Katarina; Pruessner, Marita; Lord, Catherine; Buss, Claudia; Collins, Louis; Dagher, Alain; Lupien, Sonia J

    2010-01-01

    The metabolic effects of stress are known to have significant health effects in both humans and animals. Most of these effects are mediated by the major stress hormonal axis in the body, the hypothalamic-pituitary-adrenal (HPA) axis. Within the central nervous system (CNS), the hippocampus, the amygdala and the prefrontal cortex as part of the limbic system are believed to play important roles in the regulation of the HPA axis. With the advent of structural and functional neuroimaging techniques, the role of different CNS structures in the regulation of the HPA axis can be investigated more directly. In the current paper, we summarize the findings obtained in our laboratory in the context of stress and HPA axis regulation. Our laboratory has developed and contributed to the development of manual and automated segmentation protocols from structural magnetic resonance imaging (MRI) scans for assessment of hippocampus, amygdala, medial temporal lobe and frontal lobe structures. Employing these protocols, we could show significant age-related changes in HC volumes, which were different between men and women, with pre-menopausal women showing smaller age-related volume decline compared to men. We could recently extent these findings by showing how estrogen therapy after menopause leads to higher volumes in the HC. Investigating possible neurotoxicity effects of steroids, we showed effects of long-term steroid exposure on HC volumes, and investigated variability of HC volumes in relation to HPA axis regulation in young and elderly populations. Here, we were able to follow-up from non-imaging studies showing that subjects low in self-esteem have higher cortisol stress responses, and the HC emerged as the critical link between these variables. Recently, we have made two more important discoveries with regard to HC volume: we could show that HC volume is as variable in young as it is in older adults, in subjects ranging in age from 18 to 80 years. Also, we have linked birth

  17. Progressing From Initially Ambiguous Functional Analyses: Three Case Examples

    PubMed Central

    Tiger, Jeffrey H.; Fisher, Wayne W.; Toussaint, Karen A.; Kodak, Tiffany

    2009-01-01

    Most often functional analyses are initiated using a standard set of test conditions, similar to those described by Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994). These test conditions involve the careful manipulation of motivating operations, discriminative stimuli, and reinforcement contingencies to determine the events related to the occurrence and maintenance of problem behavior. Some individuals display problem behavior that is occasioned and reinforced by idiosyncratic or otherwise unique combinations of environmental antecedents and consequences of behavior, which are unlikely to be detected using these standard assessment conditions. For these individuals, modifications to the standard test conditions or the inclusion of novel test conditions may result in clearer assessment outcomes. The current study provides three case examples of individuals whose functional analyses were initially undifferentiated; however, modifications to the standard conditions resulted in the identification of behavioral functions and the implementation of effective function-based treatments. PMID:19233611

  18. Correspondence between outcomes of brief and extended functional analyses.

    PubMed

    Kahng, S; Iwata, B A

    1999-01-01

    We compared results obtained from 50 sets of functional analysis data from assessments of self-injurious behavior (SIB), 35 of which showed clear response patterns and 15 of which were undifferentiated, with those obtained from two abbreviated methods of assessment: (a) a brief functional analysis, consisting of the first session of each condition from the full functional analysis, and (b) a within-session analysis, in which data from the brief analysis were regraphed to show minute-by-minute changes in response rates during a session. Results indicated that outcomes of the brief and within-session analyses corresponded with those of the full functional analyses in 66.0% and 68.0% of the cases, respectively. Further examination of results indicated a tendency for the brief analysis to identify a large proportion of positive cases (both true and false positives) and for the within-session analysis to identify a large proportion of negative cases (true and false negatives).

  19. Functional enrichment analyses and construction of functional similarity networks with high confidence function prediction by PFP

    PubMed Central

    2010-01-01

    Background A new paradigm of biological investigation takes advantage of technologies that produce large high throughput datasets, including genome sequences, interactions of proteins, and gene expression. The ability of biologists to analyze and interpret such data relies on functional annotation of the included proteins, but even in highly characterized organisms many proteins can lack the functional evidence necessary to infer their biological relevance. Results Here we have applied high confidence function predictions from our automated prediction system, PFP, to three genome sequences, Escherichia coli, Saccharomyces cerevisiae, and Plasmodium falciparum (malaria). The number of annotated genes is increased by PFP to over 90% for all of the genomes. Using the large coverage of the function annotation, we introduced the functional similarity networks which represent the functional space of the proteomes. Four different functional similarity networks are constructed for each proteome, one each by considering similarity in a single Gene Ontology (GO) category, i.e. Biological Process, Cellular Component, and Molecular Function, and another one by considering overall similarity with the funSim score. The functional similarity networks are shown to have higher modularity than the protein-protein interaction network. Moreover, the funSim score network is distinct from the single GO-score networks by showing a higher clustering degree exponent value and thus has a higher tendency to be hierarchical. In addition, examining function assignments to the protein-protein interaction network and local regions of genomes has identified numerous cases where subnetworks or local regions have functionally coherent proteins. These results will help interpreting interactions of proteins and gene orders in a genome. Several examples of both analyses are highlighted. Conclusion The analyses demonstrate that applying high confidence predictions from PFP can have a significant impact

  20. Brain regions involved in subprocesses of small-space episodic object-location memory: a systematic review of lesion and functional neuroimaging studies.

    PubMed

    Zimmermann, Kathrin; Eschen, Anne

    2017-04-01

    Object-location memory (OLM) enables us to keep track of the locations of objects in our environment. The neurocognitive model of OLM (Postma, A., Kessels, R. P. C., & Van Asselen, M. (2004). The neuropsychology of object-location memory. In G. L. Allen (Ed.), Human spatial memory: Remembering where (pp. 143-160). Mahwah, NJ: Lawrence Erlbaum, Postma, A., Kessels, R. P. C., & Van Asselen, M. (2008). How the brain remembers and forgets where things are: The neurocognition of object-location memory. Neuroscience & Biobehavioral Reviews, 32, 1339-1345. doi: 10.1016/j.neubiorev.2008.05.001 ) proposes that distinct brain regions are specialised for different subprocesses of OLM (object processing, location processing, and object-location binding; categorical and coordinate OLM; egocentric and allocentric OLM). It was based mainly on findings from lesion studies. However, recent episodic memory studies point to a contribution of additional or different brain regions to object and location processing within episodic OLM. To evaluate and update the neurocognitive model of OLM, we therefore conducted a systematic literature search for lesion as well as functional neuroimaging studies contrasting small-space episodic OLM with object memory or location memory. We identified 10 relevant lesion studies and 8 relevant functional neuroimaging studies. We could confirm some of the proposals of the neurocognitive model of OLM, but also differing hypotheses from episodic memory research, about which brain regions are involved in the different subprocesses of small-space episodic OLM. In addition, we were able to identify new brain regions as well as important research gaps.

  1. Dyslexic brain activation abnormalities in deep and shallow orthographies: A meta‐analysis of 28 functional neuroimaging studies

    PubMed Central

    Martin, Anna; Kronbichler, Martin

    2016-01-01

    Abstract We used coordinate‐based meta‐analysis to objectively quantify commonalities and differences of dyslexic functional brain abnormalities between alphabetic languages differing in orthographic depth. Specifically, we compared foci of under‐ and overactivation in dyslexic readers relative to nonimpaired readers reported in 14 studies in deep orthographies (DO: English) and in 14 studies in shallow orthographies (SO: Dutch, German, Italian, Swedish). The separate meta‐analyses of the two sets of studies showed universal reading‐related dyslexic underactivation in the left occipitotemporal cortex (including the visual word form area (VWFA)). The direct statistical comparison revealed higher convergence of underactivation for DO compared with SO in bilateral inferior parietal regions, but this abnormality disappeared when foci resulting from stronger dyslexic task‐negative activation (i.e., deactivation relative to baseline) were excluded. Higher convergence of underactivation for DO compared with SO was further identified in the left inferior frontal gyrus (IFG) pars triangularis, left precuneus, and right superior temporal gyrus, together with higher convergence of overactivation in the left anterior insula. Higher convergence of underactivation for SO compared with DO was found in the left fusiform gyrus, left temporoparietal cortex, left IFG pars orbitalis, and left frontal operculum, together with higher convergence of overactivation in the left precentral gyrus. Taken together, the findings support the notion of a biological unity of dyslexia, with additional orthography‐specific abnormalities and presumably different compensatory mechanisms. The results are discussed in relation to current functional neuroanatomical models of developmental dyslexia. Hum Brain Mapp 37:2676–2699, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27061464

  2. [Correlation between EEG and neuroimaging].

    PubMed

    Tobimatsu, Shozo

    2012-01-01

    The present state of knowledge of physiological mechanisms underlying nonepileptiform EEG abnormalities is reviewed to clarify the correlation between EEG and neuroimaging. Focal and widespread slow waves, background abnormalities, and bursts of rhythmic slow activity are discussed. EEG phenomena were correlated with lesion size, location, type (white matter vs. gray matter, high density vs. low density), and mass effect. Clinical and experimental accumulated over the past five decades suggest that polymorphic slow activity is generated in cerebral cortex by layers of pyramidal cells and is probably due to partial deafferentation from subcortical areas. Unilateral background activity changes are probably thalamic dysfunction, and bilateral paroxysmal slow activity is due to abnormal thalamocortical circuits combined with cortical pathology. Paroxysmal discharges indicate the presence of epilepsy with possible brain lesion(s). The EEG is a functional test and provides us complementary information to neuroimaging studies.

  3. Neural Systems Underlying Emotional and Non-emotional Interference Processing: An ALE Meta-Analysis of Functional Neuroimaging Studies

    PubMed Central

    Xu, Min; Xu, Guiping; Yang, Yang

    2016-01-01

    Understanding how the nature of interference might influence the recruitments of the neural systems is considered as the key to understanding cognitive control. Although, interference processing in the emotional domain has recently attracted great interest, the question of whether there are separable neural patterns for emotional and non-emotional interference processing remains open. Here, we performed an activation likelihood estimation meta-analysis of 78 neuroimaging experiments, and examined common and distinct neural systems for emotional and non-emotional interference processing. We examined brain activation in three domains of interference processing: emotional verbal interference in the face-word conflict task, non-emotional verbal interference in the color-word Stroop task, and non-emotional spatial interference in the Simon, SRC and Flanker tasks. Our results show that the dorsal anterior cingulate cortex (ACC) was recruited for both emotional and non-emotional interference. In addition, the right anterior insula, presupplementary motor area (pre-SMA), and right inferior frontal gyrus (IFG) were activated by interference processing across both emotional and non-emotional domains. In light of these results, we propose that the anterior insular cortex may serve to integrate information from different dimensions and work together with the dorsal ACC to detect and monitor conflicts, whereas pre-SMA and right IFG may be recruited to inhibit inappropriate responses. In contrast, the dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex (PPC) showed different degrees of activation and distinct lateralization patterns for different processing domains, which suggests that these regions may implement cognitive control based on the specific task requirements. PMID:27895564

  4. Statistical technique for analysing functional connectivity of multiple spike trains.

    PubMed

    Masud, Mohammad Shahed; Borisyuk, Roman

    2011-03-15

    A new statistical technique, the Cox method, used for analysing functional connectivity of simultaneously recorded multiple spike trains is presented. This method is based on the theory of modulated renewal processes and it estimates a vector of influence strengths from multiple spike trains (called reference trains) to the selected (target) spike train. Selecting another target spike train and repeating the calculation of the influence strengths from the reference spike trains enables researchers to find all functional connections among multiple spike trains. In order to study functional connectivity an "influence function" is identified. This function recognises the specificity of neuronal interactions and reflects the dynamics of postsynaptic potential. In comparison to existing techniques, the Cox method has the following advantages: it does not use bins (binless method); it is applicable to cases where the sample size is small; it is sufficiently sensitive such that it estimates weak influences; it supports the simultaneous analysis of multiple influences; it is able to identify a correct connectivity scheme in difficult cases of "common source" or "indirect" connectivity. The Cox method has been thoroughly tested using multiple sets of data generated by the neural network model of the leaky integrate and fire neurons with a prescribed architecture of connections. The results suggest that this method is highly successful for analysing functional connectivity of simultaneously recorded multiple spike trains.

  5. Psychological, neuroimaging, and biochemical studies on functional association between impulsive behavior and the 5-HT2A receptor gene polymorphism in humans.

    PubMed

    Nomura, Michio; Nomura, Yasuyuki

    2006-11-01

    It has been suggested that impulsive behavior is caused by dysfunctional serotonergic 5-HT neurotransmission in the central nervous system (CNS). Brain neuroimaging studies have shown that behavioral inhibition is linked to the activation of cortex sites such as the ventral frontal cortex. Positron emission tomography (PET) imaging with [(18)F]altanserin to characterize 5-HT(2A) receptor binding revealed a reduction in 5-HT(2A) binding in the ventral frontal cortex in women who had recovered from impulsive diseases. These clinical, neuroimaging, and pharmacological studies appear to support the hypothesis that functional alteration of neurotransmission due to genetic polymorphisms of the 5-HT receptors may be involved in impulsive behavior modulation. Following evaluation by a self-reporting measure, it was proposed that a polymorphism in the promoter of the 5-HT(2A) receptor gene is the underlying cause of impulsive behavior; however, this hypothesis is not convincing. We examined whether the polymorphism in the 5-HT(2A) receptor gene promoter is involved in impulsive aggression by evaluating a behavioral task (Go/No-go task) in normal volunteers. The polymorphism of the 5-HT(2A) receptor gene promoter in lymphocytes from 71 volunteers was analyzed by using PCR. Impulsivity was defined as the number of commission errors (responding when one should not) recorded during a Go/No-go task; a larger number of commission errors indicate greater difficulty in inhibiting impulsive behavior. The subjects of the A-1438A allele group for the 5-HT(2A) receptor gene made more commission errors under the punishment-reward (PR)condition in a Go/No-go task than those in the G-1438G group. In the present review, we discuss and suggest the possible involvement of the A-1438A polymorphism of the 5HT2A receptor gene promoter in impulsive behavior. This hypothesis was evaluated by using a behavioral task measure that could directly reveal impulsive behavioral traits in humans.

  6. Test-specific control conditions for functional analyses.

    PubMed

    Fahmie, Tara A; Iwata, Brian A; Querim, Angie C; Harper, Jill M

    2013-01-01

    Most functional analyses of problem behavior include a common condition (play or noncontingent reinforcement) as a control for both positive and negative reinforcement. However, test-specific conditions that control for each potential source of reinforcement may be beneficial occasionally. We compared responding during alone, ignore, play, and differential reinforcement of other behavior (DRO) control conditions for individuals whose problem behavior was maintained by positive or negative reinforcement. Results showed that all of the conditions were effective controls for problem behavior maintained by positive reinforcement; however, the DRO condition was consistently ineffective as a control for problem behavior maintained by negative reinforcement. Implications for the design of functional analyses and future research are discussed.

  7. Progressing from initially ambiguous functional analyses: three case examples.

    PubMed

    Tiger, Jeffrey H; Fisher, Wayne W; Toussaint, Karen A; Kodak, Tiffany

    2009-01-01

    Most often functional analyses are initiated using a standard set of test conditions, similar to those described by Iwata, Dorsey, Slifer, Bauman, and Richman [Iwata, B. A., Dorsey, M. F., Slifer, K. J., Bauman, K. E., & Richman, G. S. (1994). Toward a functional analysis of self-injury. Journal of Applied Behavior Analysis, 27, 197-209 (Reprinted from Analysis and Intervention in Developmental Disabilities, 2, 3-20, 1982)]. These test conditions involve the careful manipulation of motivating operations, discriminative stimuli, and reinforcement contingencies to determine the events related to the occurrence and maintenance of problem behavior. Some individuals display problem behavior that is occasioned and reinforced by idiosyncratic or otherwise unique combinations of environmental antecedents and consequences of behavior, which are unlikely to be detected using these standard assessment conditions. For these individuals, modifications to the standard test conditions or the inclusion of novel test conditions may result in clearer assessment outcomes. The current study provides three case examples of individuals whose functional analyses were initially undifferentiated; however, modifications to the standard conditions resulted in the identification of behavioral functions and the implementation of effective function-based treatments.

  8. Correspondence between outcomes of brief and extended functional analyses.

    PubMed Central

    Kahng, S; Iwata, B A

    1999-01-01

    We compared results obtained from 50 sets of functional analysis data from assessments of self-injurious behavior (SIB), 35 of which showed clear response patterns and 15 of which were undifferentiated, with those obtained from two abbreviated methods of assessment: (a) a brief functional analysis, consisting of the first session of each condition from the full functional analysis, and (b) a within-session analysis, in which data from the brief analysis were regraphed to show minute-by-minute changes in response rates during a session. Results indicated that outcomes of the brief and within-session analyses corresponded with those of the full functional analyses in 66.0% and 68.0% of the cases, respectively. Further examination of results indicated a tendency for the brief analysis to identify a large proportion of positive cases (both true and false positives) and for the within-session analysis to identify a large proportion of negative cases (true and false negatives). PMID:10396768

  9. Cognitive Neuroimaging: Cognitive Science out of the Armchair

    ERIC Educational Resources Information Center

    de Zubicaray, Greig I.

    2006-01-01

    Cognitive scientists were not quick to embrace the functional neuroimaging technologies that emerged during the late 20th century. In this new century, cognitive scientists continue to question, not unreasonably, the relevance of functional neuroimaging investigations that fail to address questions of interest to cognitive science. However, some…

  10. Training residential staff and supervisors to conduct traditional functional analyses.

    PubMed

    Lambert, Joseph M; Bloom, Sarah E; Clay, Casey J; Kunnavatana, S Shanun; Collins, Shawnee D

    2014-07-01

    In this study we extended a training outlined by Iwata to behavioral technicians working for a residential service provider for adults with developmental disabilities. Specifically, we trained ten supervisors and four assistants to organize, conduct, collect data for, and interpret the results of traditional functional analyses (FA; Iwata et al.,1994). Performance was initially low and improved across all measures following training. Results extend previous FA training research by including a tangible condition and by demonstrating that individuals with little to no prior experience conducting FAs can be taught all of the skills required to autonomously conduct them in a relatively short period of time.

  11. Sequence and Structural Analyses for Functional Non-coding RNAs

    NASA Astrophysics Data System (ADS)

    Sakakibara, Yasubumi; Sato, Kengo

    Analysis and detection of functional RNAs are currently important topics in both molecular biology and bioinformatics research. Several computational methods based on stochastic context-free grammars (SCFGs) have been developed for modeling and analysing functional RNA sequences. These grammatical methods have succeeded in modeling typical secondary structures of RNAs and are used for structural alignments of RNA sequences. Such stochastic models, however, are not sufficient to discriminate member sequences of an RNA family from non-members, and hence to detect non-coding RNA regions from genome sequences. Recently, the support vector machine (SVM) and kernel function techniques have been actively studied and proposed as a solution to various problems in bioinformatics. SVMs are trained from positive and negative samples and have strong, accurate discrimination abilities, and hence are more appropriate for the discrimination tasks. A few kernel functions that extend the string kernel to measure the similarity of two RNA sequences from the viewpoint of secondary structures have been proposed. In this article, we give an overview of recent progress in SCFG-based methods for RNA sequence analysis and novel kernel functions tailored to measure the similarity of two RNA sequences and developed for use with support vector machines (SVM) in discriminating members of an RNA family from non-members.

  12. The Roles of Left Versus Right Anterior Temporal Lobes in Conceptual Knowledge: An ALE Meta-analysis of 97 Functional Neuroimaging Studies.

    PubMed

    Rice, Grace E; Lambon Ralph, Matthew A; Hoffman, Paul

    2015-11-01

    The roles of the right and left anterior temporal lobes (ATLs) in conceptual knowledge are a source of debate between 4 conflicting accounts. Possible ATL specializations include: (1) Processing of verbal versus non-verbal inputs; (2) the involvement of word retrieval; and (3) the social content of the stimuli. Conversely, the "hub-and-spoke" account holds that both ATLs form a bilateral functionally unified system. Using activation likelihood estimation (ALE) to compare the probability of left and right ATL activation, we analyzed 97 functional neuroimaging studies of conceptual knowledge, organized according to the predictions of the three specialized hypotheses. The primary result was that ATL activation was predominately bilateral and highly overlapping for all stimulus types. Secondary to this bilateral representation, there were subtle gradations both between and within the ATLs. Activations were more likely to be left lateralized when the input was a written word or when word retrieval was required. These data are best accommodated by a graded version of the hub-and-spoke account, whereby representation of conceptual knowledge is supported through bilateral yet graded connectivity between the ATLs and various modality-specific sensory, motor, and limbic cortices.

  13. The Roles of Left Versus Right Anterior Temporal Lobes in Conceptual Knowledge: An ALE Meta-analysis of 97 Functional Neuroimaging Studies

    PubMed Central

    Rice, Grace E.; Lambon Ralph, Matthew A.; Hoffman, Paul

    2015-01-01

    The roles of the right and left anterior temporal lobes (ATLs) in conceptual knowledge are a source of debate between 4 conflicting accounts. Possible ATL specializations include: (1) Processing of verbal versus non-verbal inputs; (2) the involvement of word retrieval; and (3) the social content of the stimuli. Conversely, the “hub-and-spoke” account holds that both ATLs form a bilateral functionally unified system. Using activation likelihood estimation (ALE) to compare the probability of left and right ATL activation, we analyzed 97 functional neuroimaging studies of conceptual knowledge, organized according to the predictions of the three specialized hypotheses. The primary result was that ATL activation was predominately bilateral and highly overlapping for all stimulus types. Secondary to this bilateral representation, there were subtle gradations both between and within the ATLs. Activations were more likely to be left lateralized when the input was a written word or when word retrieval was required. These data are best accommodated by a graded version of the hub-and-spoke account, whereby representation of conceptual knowledge is supported through bilateral yet graded connectivity between the ATLs and various modality-specific sensory, motor, and limbic cortices. PMID:25771223

  14. Structural and functional analyses of biosimilar enoxaparins available in Brazil.

    PubMed

    Oliveira, Stephan-Nicollas M C G; Santos, Gustavo R C; Glauser, Bianca F; Capillé, Nina V M; Queiroz, Ismael N L; Pereira, Mariana S; Pomin, Vitor H; Mourão, Paulo A S

    2015-01-01

    Biosimilar enoxaparins have been available for clinical use in Brazil since 2009. Although their use has reduced costs of treatment expenses, their implementation still raises some concerns about efficiency, safety, regularity and reproducibility of batches. We undertook structural and functional analyses on over 90 batches of pharmaceutical-active ingredient, and 330 ones of the final products of biosimilar enoxaparins available in the Brazilian market between 2009 and 2014. Besides a nationwide-scale analysis, we have also employed methods that go beyond those recommended by the standard pharmacopeias. We have used high-resolution 2D NMR, detailed assessment of the anticoagulant and antithrombotic properties, check of side effects in experimental animals after continuous administration, and analyses of individual composing oligosaccharides. The 1D 1H NMR spectra of all batches of biosimilar enoxaparins are fairly coincident, and the resultant average spectrum is quite identical to that from the original drug. This structural equality was also assured by highly resolved 2D NMR spectra. The anticoagulant activity, determined by diverse assays and the in vivo antithrombotic and bleeding effects of the biosimilar version were confirmed as equal as of the parental enoxaparins. Structure and function of the composing oligosaccharides were identical in both enoxaparin types. No side effect was observed after continuous subcutaneous administration to rats for 30 days at the dose of 2 mg kg⁻¹ body weight. Biosimilar enoxaparins available in Brazil fulfilled the requirement of the five items defined by FDA-USA for approval of this type of drug.

  15. Functional connectivity of the left and right hippocampi: Evidence for functional lateralization along the long-axis using meta-analytic approaches and ultra-high field functional neuroimaging.

    PubMed

    Robinson, Jennifer L; Salibi, Nouha; Deshpande, Gopikrishna

    2016-07-15

    Theories regarding the functional specialization of the hippocampus date back to over a century ago. Two main theories have dominated the field. First, evidence has supported the notion of hemispheric specialization, which appears to be preserved across species. Second, an emergent and mounting set of data has suggested an anterior-posterior neurofunctional gradient. However, no study has examined these theories, and their potential interaction, using objective, robust methodological approaches. Here, we employed an established meta-analytic technique and use ultra-high field, high-resolution functional and structural neuroimaging to examine hippocampal lateralization with consideration for a long-axis differentiation. Data revealed strong support for an evolutionarily preserved hemispheric specialization. Specifically, we found intra- and interhemispheric differences with regard to anterior and posterior functional and structural connectivity, between the right and left hippocampi. For task-independent functional connectivity, we found the right anterior hippocampus to have functional connectivity with a large, distributed network, whereas the left anterior hippocampus demonstrated primarily fronto-limbic connectivity. These patterns were reversed for the posterior segmentations. Not surprisingly, for task-dependent connectivity, we found interhemispheric differences within key ipsilateral structures (i.e., parahippocampal gyrus) for both anterior and posterior segmentations. Furthermore, we identified pivotal neural hubs that share connectivity across behavioral domains, and are supported by structural connectivity (i.e., posterior cingulate cortex). Thus, our data provide evidence for a hemisphere-specific, anterior-posterior specialization of the hippocampal formation.

  16. Reprint of "Does Functional Neuroimaging Solve the Questions of Neurolinguistics?" [Brain and Language 98 (2006) 276-290

    ERIC Educational Resources Information Center

    Van Lancker Sidtis, Diana

    2007-01-01

    Neurolinguistic research has been engaged in evaluating models of language using measures from brain structure and function, and/or in investigating brain structure and function with respect to language representation using proposed models of language. While the aphasiological strategy, which classifies aphasias based on performance modality and a…

  17. What's new in neuroimaging methods?

    PubMed Central

    Bandettini, Peter A.

    2009-01-01

    The rapid advancement of neuroimaging methodology and availability has transformed neuroscience research. The answers to many questions that we ask about how the brain is organized depend on the quality of data that we are able to obtain about the locations, dynamics, fluctuations, magnitudes, and types of brain activity and structural changes. In this review, an attempt is made to take a snapshot of the cutting edge of a small component of the very rapidly evolving field of neuroimaging. For each area covered, a brief context is provided along with a summary of a few of the current developments and issues. Then, several outstanding papers, published in the past year or so, are described, providing an example of the directions in which each area is progressing. The areas covered include functional MRI (fMRI), voxel based morphometry (VBM), diffusion tensor imaging (DTI), electroencephalography (EEG), magnetoencephalography (MEG), optical imaging, and positron emission tomography (PET). More detail is included on fMRI, as subsections include: functional MRI interpretation, new functional MRI contrasts, MRI technology, MRI paradigms and processing, and endogenous oscillations in functional MRI. PMID:19338512

  18. Tinnitus: perspectives from human neuroimaging.

    PubMed

    Elgoyhen, Ana Belén; Langguth, Berthold; De Ridder, Dirk; Vanneste, Sven

    2015-10-01

    Tinnitus is the perception of phantom sound in the absence of a corresponding external source. It is a highly prevalent disorder, and most cases are caused by cochlear injury that leads to peripheral deafferentation, which results in adaptive changes in the CNS. In this article we critically assess the recent neuroimaging studies in individuals with tinnitus that suggest that the disorder is accompanied by functional and structural brain abnormalities in distributed auditory and non-auditory brain regions. Moreover, we consider how the identification of the neuronal mechanisms underlying the different forms of tinnitus would benefit from larger studies, replication and comprehensive clinical assessment of patients.

  19. Neuroimaging and Psychopharmacology

    ERIC Educational Resources Information Center

    Semrud-Clikeman, Margaret; Pliszka, Steve R.

    2005-01-01

    This review presents the most recent research concerning neuroimaging in developmental disabilities. Changes in structure and activation have been found in children with ADHD and learning disabilities, following intervention. For the children with learning disabilities changes in activation have been found following intensive behavioral and…

  20. Introduction to neuroimaging

    SciTech Connect

    Orrison, W.W.

    1989-01-01

    The author focuses on neuroradiology with emphasis on the current imaging modalities. There are chapters on angiography, myelography, nuclear medicine, ultrasonography, computer tomography (CT), and magnetic resonance (MR) imaging. The other chapters are dedicated to the spine, skull, head and neck, and pediatric neuroimaging.

  1. [Clinical neurophysiology and functional neuroimaging at the Société Française de Neurologie (1948-1998)].

    PubMed

    Mauguière, F

    1999-10-01

    The historical role of the French Neurology in the development of anatomo-clinical method is likely to explain why the first communications on electrophysiology were presented in Paris with some delay, as compared with other european societies where the neurophysiological tradition had been more lively. Though clinical neurophysiology, by essence, addresses the pathophysiology of neurological disorders, it has sometimes missed this target at its very beginning, when it aimed at providing data supposed to have some aetiological specificity, causing distrust among neurologists used to accept aetiological diagnosis only when based on post-mortem anatomical evidence. Thanks to the discovery of computerized tomography this time has been over for 25 years, and no one would question anymore the role of clinical neurophysiology and neuroimaging in Neurology, the former giving access to the timing of sensori-motor and cognitive pocesses and the latter to the localization of brain functions. This article reviews the neurophysiological literature published in the Revue Neurologique from 1948 to 1998.

  2. Neuroimaging and Fetal Alcohol Spectrum Disorders

    PubMed Central

    Norman, Andria L.; Crocker, Nicole; Mattson, Sarah N.; Riley, Edward P.

    2012-01-01

    The detrimental effects of prenatal alcohol exposure on the developing brain include structural brain anomalies as well as cognitive and behavioral deficits. Initial neuroimaging studies of fetal alcohol spectrum disorders (FASD) using magnetic resonance imaging (MRI) confirmed previous autopsy reports of overall reduction in brain volume and central nervous system (CNS) disorganization, with specific structural abnormalities of the corpus callosum, cerebellum, caudate, and hippocampus. Advances in neuroimaging techniques have allowed detection of regional increases in cortical thickness and gray matter volume along with decreased volume and disorganization of white matter in individuals with FASD. In addition, functional imaging studies have found functional and neurochemical differences in those prenatally exposed to alcohol. Behavioral alterations noted in individuals with FASD are consistent with the findings noted in the brain imaging studies. Continued neuroimaging studies are needed to further advance understanding of the neuroteratogenic effects of alcohol. PMID:19731391

  3. Neuroimaging of Freezing of Gait

    PubMed Central

    Fasano, Alfonso; Herman, Talia; Tessitore, Alessandro; Strafella, Antonio P.; Bohnen, Nicolaas I.

    2015-01-01

    Abstract Functional brain imaging techniques appear ideally suited to explore the pathophysiology of freezing of gait (FOG). In the last two decades, techniques based on magnetic resonance or nuclear medicine imaging have found a number of structural changes and functional disconnections between subcortical and cortical regions of the locomotor network in patients with FOG. FOG seems to be related in part to disruptions in the “executive-attention” network along with regional tissue loss including the premotor area, inferior frontal gyrus, precentral gyrus, the parietal and occipital areas involved in visuospatial functions of the right hemisphere. Several subcortical structures have been also involved in the etiology of FOG, principally the caudate nucleus and the locomotor centers in the brainstem. Maladaptive neural compensation may present transiently in the presence of acute conflicting motor, cognitive or emotional stimulus processing, thus causing acute network overload and resulting in episodic impairment of stepping. In this review we will summarize the state of the art of neuroimaging research for FOG. We will also discuss the limitations of current approaches and delineate the next steps of neuroimaging research to unravel the pathophysiology of this mysterious motor phenomenon. PMID:25757831

  4. Structure-function analyses of plant type III polyketide synthases.

    PubMed

    Weng, Jing-Ke; Noel, Joseph P

    2012-01-01

    Plant type III polyketide synthases (PKSs) form a superfamily of biosynthetic enzymes involved in the production of a plethora of polyketide-derived natural products important for ecological adaptations and the fitness of land plants. Moreover, tremendous interest in bioengineering of type III PKSs to produce high-value compounds is increasing. Compared to type I and type II PKSs, which form either large modular protein complexes or dissociable molecular assemblies, type III PKSs exist as smaller homodimeric proteins, technically more amenable for detailed quantitative biochemical and phylogenetic analyses. In this chapter, we summarize a collection of approaches, including bioinformatics, genetics, protein crystallography, in vitro biochemistry, and mutagenesis, together affording a comprehensive interrogation of the structure-function-evolutionary relationships in the plant type III PKS family.

  5. Evaluation of the divided attention condition during functional analyses.

    PubMed

    Fahmie, Tara A; Iwata, Brian A; Harper, Jill M; Querim, Angie C

    2013-01-01

    A common condition included in most functional analyses (FAs) is the attention condition, in which the therapist ignores the client by engaging in a solitary activity (antecedent event) but delivers attention to the client contingent on problem behavior (consequent event). The divided attention condition is similar, except that the antecedent event consists of the therapist conversing with an adult confederate. We compared the typical and divided attention conditions to determine whether behavior in general (Study 1) and problem behavior in particular (Study 2) were more sensitive to one of the test conditions. Results showed that the divided attention condition resulted in faster acquisition or more efficient FA results for 2 of 9 subjects, suggesting that the divided attention condition could be considered a preferred condition when resources are available.

  6. CONDUCTING FUNCTIONAL ANALYSES OF PROBLEM BEHAVIOR VIA TELEHEALTH

    PubMed Central

    Wacker, David P.; Lee, John F.; Padilla Dalmau, Yaniz C.; Kopelman, Todd G.; Lindgren, Scott D.; Kuhle, Jennifer; Pelzel, Kelly E.; Waldron, Debra B.

    2017-01-01

    Behavior consultants conducted functional analyses (FAs) via telehealth with 20 young children with autism spectrum disorders between the ages of 29 and 80 months who displayed problem behavior and lived an average of 222 miles from the tertiary hospital that housed the behavior consultants. Participants’ parents conducted all procedures during weekly telehealth consultations in regional clinics located an average of 15 miles from the participants’ homes. Behavior consultants briefly trained parent assistants to provide on-site support for families during consultations. FAs completed within a multielement design identified environmental variables that maintained problem behavior for 18 of the 20 cases, and interrater agreement averaged over 90%. Results suggested that behavior analysts can conduct FAs effectively and efficiently via telehealth. PMID:24114083

  7. Neuroimaging markers of glutamatergic and GABAergic systems in drug addiction: relationships to resting-state functional connectivity

    PubMed Central

    Moeller, Scott J.; London, Edythe D.; Northoff, Georg

    2015-01-01

    Drug addiction is characterized by widespread abnormalities in brain function and neurochemistry, including drug-associated effects on concentrations of the excitatory and inhibitory neurotransmitters glutamate and gamma-aminobutyric acid (GABA), respectively. In healthy individuals, these neurotransmitters drive the resting state, a default condition of brain function also disrupted in addiction. Here, our primary goal was to review in vivo magnetic resonance spectroscopy and positron emission tomography studies that examined markers of glutamate and GABA abnormalities in human drug addiction. Addicted individuals tended to show decreases in these markers compared with healthy controls, but findings also varied by individual characteristics (e.g., abstinence length). Interestingly, select corticolimbic brain regions showing glutamatergic and/or GABAergic abnormalities have been similarly implicated in resting-state functional connectivity deficits in drug addiction. Thus, our secondary goals were to provide a brief review of this resting-state literature, and an initial rationale for the hypothesis that abnormalities in glutamatergic and/or GABAergic neurotransmission may underlie resting-state functional deficits in drug addiction. In doing so, we suggest future research directions and possible treatment implications. PMID:26657968

  8. Experiencing Past and Future Personal Events: Functional Neuroimaging Evidence on the Neural Bases of Mental Time Travel

    ERIC Educational Resources Information Center

    Botzung, Anne; Denkova, Ekaterina; Manning, Lilianne

    2008-01-01

    Functional MRI was used in healthy subjects to investigate the existence of common neural structures supporting re-experiencing the past and pre-experiencing the future. Past and future events evocation appears to involve highly similar patterns of brain activation including, in particular, the medial prefrontal cortex, posterior regions and the…

  9. Neuroimaging markers of glutamatergic and GABAergic systems in drug addiction: Relationships to resting-state functional connectivity.

    PubMed

    Moeller, Scott J; London, Edythe D; Northoff, Georg

    2016-02-01

    Drug addiction is characterized by widespread abnormalities in brain function and neurochemistry, including drug-associated effects on concentrations of the excitatory and inhibitory neurotransmitters glutamate and gamma-aminobutyric acid (GABA), respectively. In healthy individuals, these neurotransmitters drive the resting state, a default condition of brain function also disrupted in addiction. Here, our primary goal was to review in vivo magnetic resonance spectroscopy and positron emission tomography studies that examined markers of glutamate and GABA abnormalities in human drug addiction. Addicted individuals tended to show decreases in these markers compared with healthy controls, but findings also varied by individual characteristics (e.g., abstinence length). Interestingly, select corticolimbic brain regions showing glutamatergic and/or GABAergic abnormalities have been similarly implicated in resting-state functional connectivity deficits in drug addiction. Thus, our secondary goals were to provide a brief review of this resting-state literature, and an initial rationale for the hypothesis that abnormalities in glutamatergic and/or GABAergic neurotransmission may underlie resting-state functional deficits in drug addiction. In doing so, we suggest future research directions and possible treatment implications.

  10. Neuroimaging Evidence of Major Morpho-Anatomical and Functional Abnormalities in the BTBR T+TF/J Mouse Model of Autism

    PubMed Central

    Dodero, Luca; Damiano, Mario; Galbusera, Alberto; Bifone, Angelo; Tsaftsaris, Sotirios A.; Scattoni, Maria Luisa; Gozzi, Alessandro

    2013-01-01

    BTBR T+tf/J (BTBR) mice display prominent behavioural deficits analogous to the defining symptoms of autism, a feature that has prompted a widespread use of the model in preclinical autism research. Because neuro-behavioural traits are described with respect to reference populations, multiple investigators have examined and described the behaviour of BTBR mice against that exhibited by C57BL/6J (B6), a mouse line characterised by high sociability and low self-grooming. In an attempt to probe the translational relevance of this comparison for autism research, we used Magnetic Resonance Imaging (MRI) to map in both strain multiple morpho-anatomical and functional neuroimaging readouts that have been extensively used in patient populations. Diffusion tensor tractography confirmed previous reports of callosal agenesis and lack of hippocampal commissure in BTBR mice, and revealed a concomitant rostro-caudal reorganisation of major cortical white matter bundles. Intact inter-hemispheric tracts were found in the anterior commissure, ventro-medial thalamus, and in a strain-specific white matter formation located above the third ventricle. BTBR also exhibited decreased fronto-cortical, occipital and thalamic gray matter volume and widespread reductions in cortical thickness with respect to control B6 mice. Foci of increased gray matter volume and thickness were observed in the medial prefrontal and insular cortex. Mapping of resting-state brain activity using cerebral blood volume weighted fMRI revealed reduced cortico-thalamic function together with foci of increased activity in the hypothalamus and dorsal hippocampus of BTBR mice. Collectively, our results show pronounced functional and structural abnormalities in the brain of BTBR mice with respect to control B6 mice. The large and widespread white and gray matter abnormalities observed do not appear to be representative of the neuroanatomical alterations typically observed in autistic patients. The presence of reduced

  11. FUNCTIONAL ANALYSIS IN PUBLIC SCHOOLS: A SUMMARY OF 90 FUNCTIONAL ANALYSES

    PubMed Central

    Mueller, Michael M; Nkosi, Ajamu; Hine, Jeffrey F

    2011-01-01

    Several review and epidemiological studies have been conducted over recent years to inform behavior analysts of functional analysis outcomes. None to date have closely examined demographic and clinical data for functional analyses conducted exclusively in public school settings. The current paper presents a data-based summary of 90 functional analyses conducted in public school settings from 2006 through 2009 for 69 students. Specifically, we present data on gender, age, race, diagnosis, topography of target behaviors, number of conditions, duration of sessions, duration of analysis, functional outcomes, setting, and person serving the role of therapist. Results suggest that functional analyses in schools are possible, practical, and produce results that are comparable to those in past research. PMID:22219531

  12. Episodic memory in former professional football players with a history of concussion: an event-related functional neuroimaging study.

    PubMed

    Ford, Jaclyn H; Giovanello, Kelly S; Guskiewicz, Kevin M

    2013-10-15

    Previous research has demonstrated that sport-related concussions can have short-term effects on cognitive processes, but the long-term consequences are less understood and warrant more research. This study was the first to use event-related functional magnetic resonance imaging (fMRI) to examine long-term differences in neural activity during memory tasks in former athletes who have sustained multiple sport-related concussions. In an event-related fMRI study, former football players reporting multiple sport-related concussions (i.e., three or more) were compared with players who reported fewer than three concussions during a memory paradigm examining item memory (i.e., memory for the particular elements of an event) and relational memory (i.e., memory for the relationships between elements). Behaviorally, we observed that concussion history did not significantly affect behavioral performance, because persons in the low and high concussion groups had equivalent performance on both memory tasks, and in addition, that concussion history was not associated with any behavioral memory measures. Despite demonstrating equivalent behavioral performance, the two groups of former players demonstrated different neural recruitment patterns during relational memory retrieval, suggesting that multiple concussions may be associated with functional inefficiencies in the relational memory network. In addition, the number of previous concussions significantly correlated with functional activity in a number of brain regions, including the medial temporal lobe and inferior parietal lobe. Our results provide important insights in understanding the long-term functional consequences of sustaining multiple sports-related concussions.

  13. Episodic Memory in Former Professional Football Players with a History of Concussion: An Event-Related Functional Neuroimaging Study

    PubMed Central

    Giovanello, Kelly S.; Guskiewicz, Kevin M.

    2013-01-01

    Abstract Previous research has demonstrated that sport-related concussions can have short-term effects on cognitive processes, but the long-term consequences are less understood and warrant more research. This study was the first to use event-related functional magnetic resonance imaging (fMRI) to examine long-term differences in neural activity during memory tasks in former athletes who have sustained multiple sport-related concussions. In an event-related fMRI study, former football players reporting multiple sport-related concussions (i.e., three or more) were compared with players who reported fewer than three concussions during a memory paradigm examining item memory (i.e., memory for the particular elements of an event) and relational memory (i.e., memory for the relationships between elements). Behaviorally, we observed that concussion history did not significantly affect behavioral performance, because persons in the low and high concussion groups had equivalent performance on both memory tasks, and in addition, that concussion history was not associated with any behavioral memory measures. Despite demonstrating equivalent behavioral performance, the two groups of former players demonstrated different neural recruitment patterns during relational memory retrieval, suggesting that multiple concussions may be associated with functional inefficiencies in the relational memory network. In addition, the number of previous concussions significantly correlated with functional activity in a number of brain regions, including the medial temporal lobe and inferior parietal lobe. Our results provide important insights in understanding the long-term functional consequences of sustaining multiple sports-related concussions. PMID:23679098

  14. A Review on the Bioinformatics Tools for Neuroimaging

    PubMed Central

    MAN, Mei Yen; ONG, Mei Sin; Mohamad, Mohd Saberi; DERIS, Safaai; SULONG, Ghazali; YUNUS, Jasmy; CHE HARUN, Fauzan Khairi

    2015-01-01

    Neuroimaging is a new technique used to create images of the structure and function of the nervous system in the human brain. Currently, it is crucial in scientific fields. Neuroimaging data are becoming of more interest among the circle of neuroimaging experts. Therefore, it is necessary to develop a large amount of neuroimaging tools. This paper gives an overview of the tools that have been used to image the structure and function of the nervous system. This information can help developers, experts, and users gain insight and a better understanding of the neuroimaging tools available, enabling better decision making in choosing tools of particular research interest. Sources, links, and descriptions of the application of each tool are provided in this paper as well. Lastly, this paper presents the language implemented, system requirements, strengths, and weaknesses of the tools that have been widely used to image the structure and function of the nervous system. PMID:27006633

  15. Co-activation Probability Estimation (CoPE): An approach for modeling functional co-activation architecture based on neuroimaging coordinates

    PubMed Central

    Chu, Congying; Fan, Lingzhong; Eickhoff, Claudia R.; Liu, Yong; Yang, Yong; Eickhoff, Simon B.; Jiang, Tianzi

    2016-01-01

    Recent progress in functional neuroimaging has prompted studies of brain activation during various cognitive tasks. Coordinate-based meta-analysis has been utilized to discover the brain regions that are consistently activated across experiments. However, within-experiment co-activation relationships, which can reflect the underlying functional relationships between different brain regions, have not been widely studied. In particular, voxel-wise co-activation, which may be able to provide a detailed configuration of the co-activation network, still needs to be modeled. To estimate the voxel-wise co-activation pattern and deduce the co-activation network, a Co-activation Probability Estimation (CoPE) method was proposed to model within-experiment activations for the purpose of defining the co-activations. A permutation test was adopted as a significance test. Moreover, the co-activations were automatically separated into local and long-range ones, based on distance. The two types of co-activations describe distinct features: the first reflects convergent activations; the second represents co-activations between different brain regions. The validation of CoPE was based on five simulation tests and one real dataset derived from studies of working memory. Both the simulated and the real data demonstrated that CoPE was not only able to find local convergence but also significant long-range co-activation. In particular, CoPE was able to identify a ‘core’ co-activation network in the working memory dataset. As a data-driven method, the CoPE method can be used to mine underlying co-activation relationships across experiments in future studies. PMID:26037052

  16. A functional neuroimaging investigation of the roles of structural complexity and task-demand during auditory sentence processing.

    PubMed

    Love, Tracy; Haist, Frank; Nicol, Janet; Swinney, David

    2006-05-01

    Using functional magnetic resonance imaging (fMRI), this study directly examined an issue that bridges the potential language processing and multi-modal views of the role of Broca's area: the effects of task-demands in language comprehension studies. We presented syntactically simple and complex sentences for auditory comprehension under three different (differentially complex) task-demand conditions: passive listening, probe verification, and theme judgment. Contrary to many language imaging findings, we found that both simple and complex syntactic structures activated left inferior frontal cortex (L-IFC). Critically, we found activation in these frontal regions increased together with increased task-demands. Specifically, tasks that required greater manipulation and comparison of linguistic material recruited L-IFC more strongly; independent of syntactic structure complexity. We argue that much of the presumed syntactic effects previously found in sentence imaging studies of L-IFC may, among other things, reflect the tasks employed in these studies and that L-IFC is a region underlying mnemonic and other integrative functions, on which much language processing may rely.

  17. Functional Analysis in Public Schools: A Summary of 90 Functional Analyses

    ERIC Educational Resources Information Center

    Mueller, Michael M.; Nkosi, Ajamu; Hine, Jeffrey F.

    2011-01-01

    Several review and epidemiological studies have been conducted over recent years to inform behavior analysts of functional analysis outcomes. None to date have closely examined demographic and clinical data for functional analyses conducted exclusively in public school settings. The current paper presents a data-based summary of 90 functional…

  18. Neuroimaging Coordination Dynamics in the Sport Sciences

    PubMed Central

    Jantzen, Kelly J.; Oullier, Olivier; Kelso, J.A. Scott

    2008-01-01

    Key methodological issues for designing, analyzing, and interpreting neuroimaging experiments are presented from the perspective of the framework of Coordination Dynamics. To this end, a brief overview of Coordination Dynamics is introduced, including the main concepts of control parameters and collective variables, theoretical modeling, novel experimental paradigms, and cardinal empirical findings. Basic conceptual and methodological issues for the design and implementation of coordination experiments in the context of neuroimaging are discussed. The paper concludes with a presentation of neuroimaging findings central to understanding the neural basis of coordination and addresses their relevance for the sport sciences. The latter include but are not restricted to learning and practice-related issues, the role of mental imagery, and the recovery of function following brain injury. PMID:18602998

  19. Neuroimaging and Recovery of Language in Aphasia

    PubMed Central

    Thompson, Cynthia K.; den Ouden, Dirk-Bart

    2010-01-01

    The use of functional neuroimaging techniques has advanced what is known about the neural mechanisms used to support language processing in aphasia resulting from brain damage. This paper highlights recent findings derived from neuroimaging studies focused on neuroplasticity of language networks, the role of the left and right hemispheres in this process, and studies examining how treatment affects the neurobiology of recovery. We point out variability across studies as well as factors related to this variability, and we emphasize challenges that remain for research. PMID:18957184

  20. Development of neural systems for reading in the monolingual and bilingual brain: new insights from functional near infrared spectroscopy neuroimaging.

    PubMed

    Jasińska, K K; Petitto, L A

    2014-01-01

    What neural changes underlie reading development in monolingual and bilingual children? We examined neural activation patterns of younger (ages 6-8) and older (ages 8-10) children and adults to see whether early-life language experience influences the development of neural systems for reading. Using functional Near Infrared Spectroscopy, we observed an age-related shift in neural recruitment of language areas (left inferior frontal gyrus [LIFG], superior temporal gyrus [STG]). Bilinguals showed a greater extent and variability of neural activation in bilateral IFG and STG, and higher cognitive areas (dorsolateral prefrontal cortex, rostrolateral prefrontal cortex). This bilingual "neural signature" reveals the extent that neural systems underlying reading development can be modified through differences in early-life language experience.

  1. Coordinate based meta-analysis of functional neuroimaging data using activation likelihood estimation; full width half max and group comparisons.

    PubMed

    Tench, Christopher R; Tanasescu, Radu; Auer, Dorothee P; Cottam, William J; Constantinescu, Cris S

    2014-01-01

    Coordinate based meta-analysis (CBMA) is used to find regions of consistent activation across fMRI and PET studies selected for their functional relevance to a hypothesis. Results are clusters of foci where multiple studies report in the same spatial region, indicating functional relevance. Contrast meta-analysis finds regions where there are consistent differences in activation pattern between two groups. The activation likelihood estimate methods tackle these problems, but require a specification of uncertainty in foci location: the full width half max (FWHM). Results are sensitive to FWHM. Furthermore, contrast meta-analysis requires correction for multiple statistical tests. Consequently it is sensitive only to very significant localised differences that produce very small p-values, which remain significant after correction; subtle diffuse differences between the groups can be overlooked. In this report we redefine the FWHM parameter, by analogy with a density clustering algorithm, and provide a method to estimate it. The FWHM is modified to account for the number of studies in the analysis, and represents a substantial change to the CBMA philosophy that can be applied to the current algorithms. Consequently we observe more reliable detection of clusters when there are few studies in the CBMA, and a decreasing false positive rate with larger study numbers. By contrast the standard definition (FWHM independent of the number of studies) is demonstrated to paradoxically increase the false positive rate as the number of studies increases, while reducing ability to detect true clusters for small numbers of studies. We also provide an algorithm for contrast meta-analysis, which includes a correction for multiple correlated tests that controls for the proportion of false clusters expected under the null hypothesis. Furthermore, we detail an omnibus test of difference between groups that is more sensitive than contrast meta-analysis when differences are diffuse. This

  2. Neuroimaging measures of error-processing: Extracting reliable signals from event-related potentials and functional magnetic resonance imaging.

    PubMed

    Steele, Vaughn R; Anderson, Nathaniel E; Claus, Eric D; Bernat, Edward M; Rao, Vikram; Assaf, Michal; Pearlson, Godfrey D; Calhoun, Vince D; Kiehl, Kent A

    2016-05-15

    Error-related brain activity has become an increasingly important focus of cognitive neuroscience research utilizing both event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI). Given the significant time and resources required to collect these data, it is important for researchers to plan their experiments such that stable estimates of error-related processes can be achieved efficiently. Reliability of error-related brain measures will vary as a function of the number of error trials and the number of participants included in the averages. Unfortunately, systematic investigations of the number of events and participants required to achieve stability in error-related processing are sparse, and none have addressed variability in sample size. Our goal here is to provide data compiled from a large sample of healthy participants (n=180) performing a Go/NoGo task, resampled iteratively to demonstrate the relative stability of measures of error-related brain activity given a range of sample sizes and event numbers included in the averages. We examine ERP measures of error-related negativity (ERN/Ne) and error positivity (Pe), as well as event-related fMRI measures locked to False Alarms. We find that achieving stable estimates of ERP measures required four to six error trials and approximately 30 participants; fMRI measures required six to eight trials and approximately 40 participants. Fewer trials and participants were required for measures where additional data reduction techniques (i.e., principal component analysis and independent component analysis) were implemented. Ranges of reliability statistics for various sample sizes and numbers of trials are provided. We intend this to be a useful resource for those planning or evaluating ERP or fMRI investigations with tasks designed to measure error-processing.

  3. Systems Biology, Neuroimaging, Neuropsychology, Neuroconnectivity and Traumatic Brain Injury

    PubMed Central

    Bigler, Erin D.

    2016-01-01

    The patient who sustains a traumatic brain injury (TBI) typically undergoes neuroimaging studies, usually in the form of computed tomography (CT) and magnetic resonance imaging (MRI). In most cases the neuroimaging findings are clinically assessed with descriptive statements that provide qualitative information about the presence/absence of visually identifiable abnormalities; though little if any of the potential information in a scan is analyzed in any quantitative manner, except in research settings. Fortunately, major advances have been made, especially during the last decade, in regards to image quantification techniques, especially those that involve automated image analysis methods. This review argues that a systems biology approach to understanding quantitative neuroimaging findings in TBI provides an appropriate framework for better utilizing the information derived from quantitative neuroimaging and its relation with neuropsychological outcome. Different image analysis methods are reviewed in an attempt to integrate quantitative neuroimaging methods with neuropsychological outcome measures and to illustrate how different neuroimaging techniques tap different aspects of TBI-related neuropathology. Likewise, how different neuropathologies may relate to neuropsychological outcome is explored by examining how damage influences brain connectivity and neural networks. Emphasis is placed on the dynamic changes that occur following TBI and how best to capture those pathologies via different neuroimaging methods. However, traditional clinical neuropsychological techniques are not well suited for interpretation based on contemporary and advanced neuroimaging methods and network analyses. Significant improvements need to be made in the cognitive and behavioral assessment of the brain injured individual to better interface with advances in neuroimaging-based network analyses. By viewing both neuroimaging and neuropsychological processes within a systems biology

  4. Psychotherapy and Neuroimaging

    PubMed Central

    Fournier, Jay C.; Price, Rebecca B.

    2014-01-01

    Technological advances in neuroimaging have enabled researchers to examine, in vivo, the relationship between psychotherapeutic interventions and markers of brain activity. This review focuses on two kinds of neuroimaging studies in psychotherapy: those that examine the patterns of brain activity associated with response to treatments and those that examine the changes that occur in brain activity during treatment. A general, hypothetical neural model of psychotherapy is presented, and support for the model is evaluated across anxiety disorders and major depression. Neuroimaging studies are broadly consistent in observing associations between response to psychotherapy and baseline activity in several key regions within the prefrontal cortex, basal ganglia, and limbic areas. These regions are involved in the generation and regulation of emotion, fear responding, and response to reward. Pre-post examinations of change following psychotherapy also typically observe that psychological treatments for anxiety and depression can affect neural activity in these regions. Despite general consensus that activity in these regions is associated with psychotherapy, substantial discrepancy persists regarding the precise direction of the observed relationships. Methodological challenges of the existing literature are considered, and future directions are discussed. PMID:25346646

  5. Retrospective study on structural neuroimaging in first-episode psychosis

    PubMed Central

    Silva-dos-Santos, Amilcar; Talina, Miguel Cotrim

    2016-01-01

    Background. No consensus between guidelines exists regarding neuroimaging in first-episode psychosis. The purpose of this study is to assess anomalies found in structural neuroimaging exams (brain computed tomography (CT) and magnetic resonance imaging (MRI)) in the initial medical work-up of patients presenting first-episode psychosis. Methods. The study subjects were 32 patients aged 18–48 years (mean age: 29.6 years), consecutively admitted with first-episode psychosis diagnosis. Socio-demographic and clinical data and neuroimaging exams (CT and MRI) were retrospectively studied. Diagnostic assessments were made using the Operational Criteria Checklist +. Neuroimaging images (CT and MRI) and respective reports were analysed by an experienced consultant psychiatrist. Results. None of the patients had abnormalities in neuroimaging exams responsible for psychotic symptoms. Thirty-seven percent of patients had incidental brain findings not causally related to the psychosis (brain atrophy, arachnoid cyst, asymmetric lateral ventricles, dilated lateral ventricles, plagiocephaly and falx cerebri calcification). No further medical referral was needed for any of these patients. No significant differences regarding gender, age, diagnosis, duration of untreated psychosis, in-stay and cannabis use were found between patients who had neuroimaging abnormalities versus those without. Discussion. This study suggests that structural neuroimaging exams reveal scarce abnormalities in young patients with first-episode psychosis. Structural neuroimaging is especially useful in first-episode psychosis patients with neurological symptoms, atypical clinical picture and old age. PMID:27257547

  6. A conceptual overview and critique of functional neuroimaging techniques in humans: I. MRI/FMRI and PET.

    PubMed

    Aine, C J

    1995-01-01

    A critical evaluation of current, noninvasive brain-mapping techniques indicates that no one technique in isolation can adequately address the varied questions of interest to basic researchers and clinicians. Consequently, an integrated analysis of anatomical and functional measurements has become the ultimate goal to better characterize the nature of neuronal and hemodynamic responses to sensory and cognitive stimulation. Such an analysis will optimize both spatial and temporal resolution, thereby enabling patterns of activation to be followed throughout the central nervous system, a prerequisite for examining stages of information processing. This review, written in two parts, provides a conceptual overview of three techniques (MRI/fMRI, PET, and MEG/EEG) and examines current efforts at integrating these measures. Each technique is initially evaluated in isolation by considering a set of primary issues (e.g., spatial resolution, temporal resolution, the nature of the signal, individual variability, repeatability, etc.). The first part compares and contrasts MRI/fMRI techniques with PET. Part II, which examines MEG/EEG techniques and current attempts at integrating techniques, will appear in a subsequent volume. This two-part review focuses on issues, not results per se, and it is assumed that the reader is not proficient in any of the techniques described.

  7. Comparison of Obese Adults with Poor versus Good Sleep Quality during a Functional Neuroimaging Delay Discounting Task: A Pilot Study

    PubMed Central

    Martin, Laura E.; Pollack, Lauren; McCune, Ashley; Schulte, Erica; Savage, Cary R.; Lundgren, Jennifer D.

    2015-01-01

    This study aimed to determine if obese adults with poor versus good sleep quality demonstrate reduced self-regulatory capacity and different patterns of neural activation when making impulsive monetary choices. Six obese, good quality sleepers (M age = 44.7 years, M BMI = 83.1 kg/m2) were compared to 13 obese, poor quality sleepers (M age = 42.6, M BMI = 39.2 kg/m2) on sleep and eating behavior and brain activation in prefrontal and insular regions while engaging in a delay discounting task during functional magnetic resonance imaging (fMRI). Poor quality sleepers demonstrated significantly lower brain activation in the right inferior frontal gyrus, right middle frontal gyrus, and bilateral insula when making immediate and smaller (impulsive) monetary choices compared to the baseline condition. Behaviorally, poor compared to good quality sleepers reported higher scores in the night eating questionnaire. Obese adults with poor sleep quality demonstrate decreased brain activation in multiple regions that regulate cognitive control and interceptive awareness, possibly reducing self-regulatory capacity when making immediately gratifying decisions. PMID:26358975

  8. Neuroimaging in repetitive brain trauma

    PubMed Central

    2014-01-01

    Sports-related concussions are one of the major causes of mild traumatic brain injury. Although most patients recover completely within days to weeks, those who experience repetitive brain trauma (RBT) may be at risk for developing a condition known as chronic traumatic encephalopathy (CTE). While this condition is most commonly observed in athletes who experience repetitive concussive and/or subconcussive blows to the head, such as boxers, football players, or hockey players, CTE may also affect soldiers on active duty. Currently, the only means by which to diagnose CTE is by the presence of phosphorylated tau aggregations post-mortem. Non-invasive neuroimaging, however, may allow early diagnosis as well as improve our understanding of the underlying pathophysiology of RBT. The purpose of this article is to review advanced neuroimaging methods used to investigate RBT, including diffusion tensor imaging, magnetic resonance spectroscopy, functional magnetic resonance imaging, susceptibility weighted imaging, and positron emission tomography. While there is a considerable literature using these methods in brain injury in general, the focus of this review is on RBT and those subject populations currently known to be susceptible to RBT, namely athletes and soldiers. Further, while direct detection of CTE in vivo has not yet been achieved, all of the methods described in this review provide insight into RBT and will likely lead to a better characterization (diagnosis), in vivo, of CTE than measures of self-report. PMID:25031630

  9. Neuroimaging in repetitive brain trauma.

    PubMed

    Ng, Thomas Sc; Lin, Alexander P; Koerte, Inga K; Pasternak, Ofer; Liao, Huijun; Merugumala, Sai; Bouix, Sylvain; Shenton, Martha E

    2014-01-01

    Sports-related concussions are one of the major causes of mild traumatic brain injury. Although most patients recover completely within days to weeks, those who experience repetitive brain trauma (RBT) may be at risk for developing a condition known as chronic traumatic encephalopathy (CTE). While this condition is most commonly observed in athletes who experience repetitive concussive and/or subconcussive blows to the head, such as boxers, football players, or hockey players, CTE may also affect soldiers on active duty. Currently, the only means by which to diagnose CTE is by the presence of phosphorylated tau aggregations post-mortem. Non-invasive neuroimaging, however, may allow early diagnosis as well as improve our understanding of the underlying pathophysiology of RBT. The purpose of this article is to review advanced neuroimaging methods used to investigate RBT, including diffusion tensor imaging, magnetic resonance spectroscopy, functional magnetic resonance imaging, susceptibility weighted imaging, and positron emission tomography. While there is a considerable literature using these methods in brain injury in general, the focus of this review is on RBT and those subject populations currently known to be susceptible to RBT, namely athletes and soldiers. Further, while direct detection of CTE in vivo has not yet been achieved, all of the methods described in this review provide insight into RBT and will likely lead to a better characterization (diagnosis), in vivo, of CTE than measures of self-report.

  10. Systematic Redaction for Neuroimage Data

    PubMed Central

    Matlock, Matt; Schimke, Nakeisha; Kong, Liang; Macke, Stephen; Hale, John

    2013-01-01

    In neuroscience, collaboration and data sharing are undermined by concerns over the management of protected health information (PHI) and personal identifying information (PII) in neuroimage datasets. The HIPAA Privacy Rule mandates measures for the preservation of subject privacy in neuroimaging studies. Unfortunately for the researcher, the management of information privacy is a burdensome task. Wide scale data sharing of neuroimages is challenging for three primary reasons: (i) A dearth of tools to systematically expunge PHI/PII from neuroimage data sets, (ii) a facility for tracking patient identities in redacted datasets has not been produced, and (iii) a sanitization workflow remains conspicuously absent. This article describes the XNAT Redaction Toolkit—an integrated redaction workflow which extends a popular neuroimage data management toolkit to remove PHI/PII from neuroimages. Quickshear defacing is also presented as a complementary technique for deidentifying the image data itself. Together, these tools improve subject privacy through systematic removal of PII/PHI. PMID:24179597

  11. Pituitary gland in psychiatric disorders: a review of neuroimaging findings.

    PubMed

    Atmaca, Murad

    2014-08-01

    In this paper, it was reviewed neuroimaging results of the pituitary gland in psychiatric disorders, particularly schizophrenia, mood disorders, anxiety disorders, and somatoform disorders. The author made internet search in detail by using PubMed database including the period between 1980 and 2012 October. It was included in the articles in English, Turkish and French languages on pituitary gland in psychiatric disorders through structural or functional neuroimaging results. After searching mentioned in the Methods section in detail, investigations were obtained on pituitary gland neuroimaging in a variety of psychiatric disorders. There have been so limited investigations on pituitary neuroimaging in psychiatric disorders including major psychiatric illnesses like schizophrenia and mood disorders. Current findings are so far from the generalizability of the results. For this reason, it is required to perform much more neuroimaging studies of pituitary gland in all psychiatric disorders to reach the diagnostic importance of measuring it.

  12. Neuroimaging studies of social cognition in schizophrenia.

    PubMed

    Fujiwara, Hironobu; Yassin, Walid; Murai, Toshiya

    2015-05-01

    Impaired social cognition is considered a core contributor to unfavorable psychosocial functioning in schizophrenia. Rather than being a unitary process, social cognition is a collection of multifaceted processes that recruit multiple brain structures, thus structural and functional neuroimaging techniques are ideal methodologies for revealing the underlying pathophysiology of impaired social cognition. Many neuroimaging studies have suggested that in addition to white-matter deficits, schizophrenia is associated with decreased gray-matter volume in multiple brain areas, especially fronto-temporal and limbic regions. However, few schizophrenia studies have examined associations between brain abnormalities and social cognitive disabilities. During the last decade, we have investigated structural brain abnormalities in schizophrenia using high-resolution magnetic resonance imaging, and our findings have been confirmed by us and others. By assessing different types of social cognitive abilities, structural abnormalities in multiple brain regions have been found to be associated with disabilities in social cognition, such as recognition of facial emotion, theory of mind, and empathy. These structural deficits have also been associated with alexithymia and quality of life in ways that are closely related to the social cognitive disabilities found in schizophrenia. Here, we overview a series of neuroimaging studies from our laboratory that exemplify current research into this topic, and discuss how it can be further tackled using recent advances in neuroimaging technology.

  13. Deconvolution analyses with tent functions reveal delayed and long-sustained increases of BOLD signals with acupuncture stimulation.

    PubMed

    Murase, Tomokazu; Umeda, Masahiro; Fukunaga, Masaki; Tanaka, Chuzo; Higuchi, Toshihiro

    2013-01-01

    We used deconvolution analysis to examine temporal changes in brain activity after acupuncture stimulation and assess brain responses without expected reference functions. We also examined temporal changes in brain activity after sham acupuncture (noninsertive) and scrubbing stimulation. We divided 26 healthy right-handed adults into a group of 13 who received real acupuncture with manual manipulation and a group of 13 who received both tactical stimulations. Functional magnetic resonance imaging (fMRI) sequences consisted of four 15-s stimulation blocks (ON) interspersed between one 30-s and four 45-s rest blocks (OFF) for a total scanning time of 270 s. We analyzed data by using Statistical Parametric Mapping 8 (SPM8), MarsBaR, and Analysis of Functional NeuroImages (AFNI) software. For statistical analysis, we used 3dDeconvolve, part of the AFNI package, to extract the impulse response functions (IRFs) of the fMRI signals on a voxel-wise basis, and we tested the time courses of the extracted IRFs for the stimulations. We found stimulus-specific impulse responses of blood oxygen level-dependent (BOLD) signals in various brain regions. We observed significantly delayed and long-sustained increases of BOLD signals in several brain regions following real acupuncture compared to sham acupuncture and palm scrubbing, which we attribute to peripheral nocireceptors, flare responses, and processing of the central nervous system. Acupuncture stimulation induced continued activity that was stronger than activity after the other stimulations. We used tent function deconvolution to process fMRI data for acupuncture stimulation and found delayed increasing and delayed decreasing changes in BOLD signal in the somatosensory areas and areas related to pain perception. Deconvolution analyses with tent functions are expected to be useful in extracting complicated and associated brain activity that is delayed and sustained for a long period after various stimulations.

  14. Multimodal Neuroimaging-Informed Clinical Applications in Neuropsychiatric Disorders

    PubMed Central

    O’Halloran, Rafael; Kopell, Brian H.; Sprooten, Emma; Goodman, Wayne K.; Frangou, Sophia

    2016-01-01

    Recent advances in neuroimaging data acquisition and analysis hold the promise to enhance the ability to make diagnostic and prognostic predictions and perform treatment planning in neuropsychiatric disorders. Prior research using a variety of types of neuroimaging techniques has confirmed that neuropsychiatric disorders are associated with dysfunction in anatomical and functional brain circuits. We first discuss current challenges associated with the identification of reliable neuroimaging markers for diagnosis and prognosis in mood disorders and for neurosurgical treatment planning for deep brain stimulation (DBS). We then present data on the use of neuroimaging for the diagnosis and prognosis of mood disorders and for DBS treatment planning. We demonstrate how multivariate analyses of functional activation and connectivity parameters can be used to differentiate patients with bipolar disorder from those with major depressive disorder and non-affective psychosis. We also present data on connectivity parameters that mediate acute treatment response in affective and non-affective psychosis. We then focus on precision mapping of functional connectivity in native space. We describe the benefits of integrating anatomical fiber reconstruction with brain functional parameters and cortical surface measures to derive anatomically informed connectivity metrics within the morphological context of each individual brain. We discuss how this approach may be particularly promising in psychiatry, given the clinical and etiological heterogeneity of the disorders, and particularly in treatment response prediction and planning. Precision mapping of connectivity is essential for DBS. In DBS, treatment electrodes are inserted into positions near key gray matter nodes within the circuits considered relevant to disease expression. However, targeting white matter tracts that underpin connectivity within these circuits may increase treatment efficacy and tolerability therefore relevant

  15. Multimodal Neuroimaging-Informed Clinical Applications in Neuropsychiatric Disorders.

    PubMed

    O'Halloran, Rafael; Kopell, Brian H; Sprooten, Emma; Goodman, Wayne K; Frangou, Sophia

    2016-01-01

    Recent advances in neuroimaging data acquisition and analysis hold the promise to enhance the ability to make diagnostic and prognostic predictions and perform treatment planning in neuropsychiatric disorders. Prior research using a variety of types of neuroimaging techniques has confirmed that neuropsychiatric disorders are associated with dysfunction in anatomical and functional brain circuits. We first discuss current challenges associated with the identification of reliable neuroimaging markers for diagnosis and prognosis in mood disorders and for neurosurgical treatment planning for deep brain stimulation (DBS). We then present data on the use of neuroimaging for the diagnosis and prognosis of mood disorders and for DBS treatment planning. We demonstrate how multivariate analyses of functional activation and connectivity parameters can be used to differentiate patients with bipolar disorder from those with major depressive disorder and non-affective psychosis. We also present data on connectivity parameters that mediate acute treatment response in affective and non-affective psychosis. We then focus on precision mapping of functional connectivity in native space. We describe the benefits of integrating anatomical fiber reconstruction with brain functional parameters and cortical surface measures to derive anatomically informed connectivity metrics within the morphological context of each individual brain. We discuss how this approach may be particularly promising in psychiatry, given the clinical and etiological heterogeneity of the disorders, and particularly in treatment response prediction and planning. Precision mapping of connectivity is essential for DBS. In DBS, treatment electrodes are inserted into positions near key gray matter nodes within the circuits considered relevant to disease expression. However, targeting white matter tracts that underpin connectivity within these circuits may increase treatment efficacy and tolerability therefore relevant

  16. A probabilistic functional atlas of the VIM nucleus constructed from pre-, intra- and postoperative electrophysiological and neuroimaging data acquired during the surgical treatment of Parkinson's disease patients.

    PubMed

    Nowinski, Wieslaw L; Belov, Dmitry; Thirunavuukarasuu, A; Benabid, Alim Louis

    2005-01-01

    We have previously introduced a concept of a probabilistic functional atlas (PFA) to overcome limitations of the current electronic stereotactic brain atlases: anatomical nature, spatial sparseness, inconsistency and lack of population information. The PFA for the STN has already been developed. This work addresses construction of the PFA for the ventrointermediate nucleus (PFA-VIM). The PFA-VIM is constructed from pre-, intra- and postoperative electrophysiological and neuroimaging data acquired during the surgical treatment of Parkinson's disease patients. The data contain the positions of the chronically implanted electrodes and their best contacts. For each patient, the intercommissural distance, height of the thalamus and width of the third ventricle were measured. An algorithm was developed to convert these data into the PFA-VIM, and to present them on axial, coronal and sagittal planes and in 3-D. The PFA-VIM gives a spatial distribution of the best contacts, and its probability is proportional to best contact concentration in a given location. The region with the highest probability corresponds to the best target. The PFA-VIM is calculated with 0.25-mm3 resolution from 107 best contacts in two situations: with and without lateral compensation against the width of the third ventricle. For the PFA-VIM compensated laterally, the anterior, lateral and dorsal coordinates of the mean value are (in mm) 6.24, 13.83, 1.68 for the left VIM and 6.54, -13.84, 2.10 for the right VIM. The coordinates of the mean value of the highest probability region along with the highest number of the best contacts (P) are: 6.25, 14.25, 1.75, P = 16, for the left VIM, and 6.0, -14.0, 1.00, P = 18, for the right VIM. The coordinate system origin is at the posterior commissure. For the PFA-VIM not compensated laterally, the coordinates of the mean value are 6.24, 13.99, 1.68 for the left VIM and 6.53, -14.13, 2.10 for the right VIM. The coordinates of the mean value of the highest

  17. The open-source neuroimaging research enterprise.

    PubMed

    Marcus, Daniel S; Archie, Kevin A; Olsen, Timothy R; Ramaratnam, Mohana

    2007-11-01

    While brain imaging in the clinical setting is largely a practice of looking at images, research neuroimaging is a quantitative and integrative enterprise. Images are run through complex batteries of processing and analysis routines to generate numeric measures of brain characteristics. Other measures potentially related to brain function - demographics, genetics, behavioral tests, neuropsychological tests - are key components of most research studies. The canonical scanner - PACS - viewing station axis used in clinical practice is therefore inadequate for supporting neuroimaging research. Here, we model the neuroimaging research enterprise as a workflow. The principal components of the workflow include data acquisition, data archiving, data processing and analysis, and data utilization. We also describe a set of open-source applications to support each step of the workflow and the transitions between these steps. These applications include DIGITAL IMAGING AND COMMUNICATIONS IN MEDICINE viewing and storage tools, the EXTENSIBLE NEUROIMAGING ARCHIVE TOOLKIT data archiving and exploration platform, and an engine for running processing/analysis pipelines. The overall picture presented is aimed to motivate open-source developers to identify key integration and communication points for interoperating with complimentary applications.

  18. Training Teachers to Conduct Trial-Based Functional Analyses

    ERIC Educational Resources Information Center

    Kunnavatana, S. Shanun; Bloom, Sarah E.; Samaha, Andrew L.; Dayton, Elizabeth

    2013-01-01

    The trial-based functional analysis (FA) is a promising approach to identification of behavioral function and is especially suited for use in educational settings. Not all studies on trial-based FA have included teachers as therapists, and those studies that have, included minimal information on teacher training. The purpose of this study was to…

  19. The safety of functional analyses of self-injurious behavior.

    PubMed

    Kahng, SungWoo; Hausman, Nicole L; Fisher, Alyssa B; Donaldson, Jeanne M; Cox, Jessica R; Lugo, Monica; Wiskow, Katie M

    2015-01-01

    Functional analysis is the most precise method of identifying variables that maintain self-injurious behavior (SIB), and its use may lead to more effective treatment. One criticism and potential limitation of a functional analysis is that it may unnecessarily expose individuals to a higher risk of injury (Betz & Fisher, 2011). The purpose of this study was to determine if there were higher levels and severity of injury during the functional analysis than outside the functional analysis. We conducted a retrospective records review of 99 participants admitted to an inpatient unit for the treatment of SIB. The results showed that injury rates were relatively low across all situations and that when injuries occurred, they were usually not severe. These findings suggest that the functional analysis of SIB is relatively safe when appropriate precautions are taken.

  20. Provenance in Neuroimaging

    PubMed Central

    MacKenzie-Graham, Allan J.; Van Horn, John D.; Woods, Roger P.; Crawford, Karen L.

    2008-01-01

    Provenance, the description of the history of a set of data, has grown more important with the proliferation of research consortia-related efforts in neuroimaging. Knowledge about the origin and history of an image is crucial for establishing data and results quality; detailed information about how it was processed, including the specific software routines and operating systems that were used, is necessary for proper interpretation, high fidelity replication and re-use. We have drafted a mechanism for describing provenance in a simple and easy to use environment, alleviating the burden of documentation from the user while still providing a rich description of an image’s provenance. This combination of ease of use and highly descriptive metadata should greatly facilitate the collection of provenance and subsequent sharing of data. PMID:18519166

  1. [The advantages and limitations of brain function analyses by PET].

    PubMed

    Kato, M; Taniwaki, T; Kuwabara, Y

    2000-12-01

    PET has been proved to be a powerful tool for exploring the brain function. We discussed the advantages and limitations of PET for analyzing the brain function on the basis of our clinical and experimental experiences of functional imaging. A multimodality PET study measuring cerebral energy metabolism (CMRO2 and CMRglc), cerebral blood flow (CBF), oxygen extraction fraction (OEF) and neurotransmitter function (presynaptic and postsynaptic) opens up a closer insight into a precise pathophysiology of the brain dysfunction: In cerebral infarction, it reveals a state of "misery perfusion" in the acute stage, "luxury perfusion" in the intermediate stage, and proportionately decreased CBF and CMRO2 in the chronic stage. Neurotransmitter function may identify specifically a neuronal subgroup of dysfunction. Owing to the low temporal resolution of PET, a neuronal activity may propagate transsynaptically to remote areas during the period of scanning, resulting in an obscured primary site of the neuronal activity. Uncoupling between neuronal activities and cerebral energy metabolism/CBF may occur under a certain state of brain pathology, particularly after an acute destructive lesion, according to our experimental studies. Neurotransmitter function may reveal the effect of drugs on the brain function, and may be useful for developing a new method of drug therapy for brain diseases in the future.

  2. Comparative analyses of nuclear proteome: extending its function

    PubMed Central

    Narula, Kanika; Datta, Asis; Chakraborty, Niranjan; Chakraborty, Subhra

    2013-01-01

    Organeller proteomics is an emerging technology that is critical in determining the cellular signal transduction pathways. Nucleus, the regulatory hub of the eukaryotic cell is a dynamic system and a repository of various macromolecules that serve as modulators of such signaling that dictate cell fate decisions. Nuclear proteins (NPs) are predicted to comprise about 10–20% of the total cellular proteins, suggesting the involvement of the nucleus in a number of diverse functions. Indeed, NPs constitute a highly organized but complex network that plays diverse roles during development and physiological processes. In plants, relatively little is known about the nature of the molecular components and mechanisms involved in coordinating NP synthesis, their action and function. Proteomic study hold promise to understand the molecular basis of nuclear function using an unbiased comparative and differential approach. We identified a few hundred proteins that include classical and non-canonical nuclear components presumably associated with variety of cellular functions impinging on the complexity of nuclear proteome. Here, we review the nuclear proteome based on our own findings, available literature, and databases focusing on detailed comparative analysis of NPs and their functions in order to understand how plant nucleus works. The review also shed light on the current status of plant nuclear proteome and discusses the future prospect. PMID:23637696

  3. Crustal Structure of North Iraq from Receiver Function Analyses

    DTIC Science & Technology

    2008-09-01

    1999), Park and Levin (2000), and Helffrich (2006). The current approach is based on the techniques by Zhu and Kanamori (2000), Julià et al. (2000...and H. Kanamori (2000). Moho depth variation in southern California from teleseismic receiver functions, J. Geophys. Res. 105: 2969–2980. Ammon

  4. The Effects of Establishing Operations on Functional Analyses Conditions

    ERIC Educational Resources Information Center

    Thomas, Craig A.; Fraiser, Jade

    2005-01-01

    A functional analysis was performed on a five-year-old nonverbal Autistic female with severe self-injurious behaviors. The self-injurious behaviors (hand-to-head, hand-to-jaw, hand-to-face) and loud vocalizations were targeted. Two types of sessions, enriched environment and instructor controlled preferred stimuli, were alternated throughout the…

  5. Applying a Mixed Methods Framework to Differential Item Function Analyses

    ERIC Educational Resources Information Center

    Hitchcock, John H.; Johanson, George A.

    2015-01-01

    Understanding the reason(s) for Differential Item Functioning (DIF) in the context of measurement is difficult. Although identifying potential DIF items is typically a statistical endeavor, understanding the reasons for DIF (and item repair or replacement) might require investigations that can be informed by qualitative work. Such work is…

  6. Improved response functions for gamma-ray skyshine analyses

    NASA Astrophysics Data System (ADS)

    Shultis, J. K.; Faw, R. E.; Deng, X.

    1992-09-01

    A computationally simple method, based on line-beam response functions, is refined for estimating gamma skyshine dose rates. Critical to this method is the availability of an accurate approximation for the line-beam response function (LBRF). In this study, the LBRF is evaluated accurately with the point-kernel technique using recent photon interaction data. Various approximations to the LBRF are considered, and a three parameter formula is selected as the most practical approximation. By fitting the approximating formula to point-kernel results, a set of parameters is obtained that allows the LBRF to be quickly and accurately evaluated for energies between 0.01 and 15 MeV, for source-to-detector distances from 1 to 3000 m, and for beam angles from 0 to 180 degrees. This re-evaluation of the approximate LBRF gives better accuracy, especially at low energies, over a greater source-to-detector range than do previous LBRF approximations. A conical beam response function is also introduced for application to skyshine sources that are azimuthally symmetric about a vertical axis. The new response functions are then applied to three simple skyshine geometries (an open silo geometry, an infinite wall, and a rectangular four-wall building) and the results are compared to previous calculations and benchmark data.

  7. False-Positive Tangible Outcomes of Functional Analyses

    ERIC Educational Resources Information Center

    Rooker, Griffin W.; Iwata, Brian A.; Harper, Jill M.; Fahmie, Tara A.; Camp, Erin M.

    2011-01-01

    Functional analysis (FA) methodology is the most precise method for identifying variables that maintain problem behavior. Occasionally, however, results of an FA may be influenced by idiosyncratic sensitivity to aspects of the assessment conditions. For example, data from several studies suggest that inclusion of a tangible condition during an FA…

  8. False-positive tangible outcomes of functional analyses.

    PubMed

    Rooker, Griffin W; Iwata, Brian A; Harper, Jill M; Fahmie, Tara A; Camp, Erin M

    2011-01-01

    Functional analysis (FA) methodology is the most precise method for identifying variables that maintain problem behavior. Occasionally, however, results of an FA may be influenced by idiosyncratic sensitivity to aspects of the assessment conditions. For example, data from several studies suggest that inclusion of a tangible condition during an FA may be prone to a false-positive outcome, although the extent to which tangible reinforcement routinely produces such outcomes is unknown. We examined susceptibility to tangible reinforcement by determining whether a new response was acquired more readily when exposed to a tangible contingency relative to others commonly used in an FA (Study 1), and whether problem behavior known not to have a social function nevertheless emerged when exposed to tangible reinforcement (Study 2). Results indicated that inclusion of items in the tangible condition should be done with care and that selection should be based on those items typically found in the individual's environment.

  9. Plant Ion Channels: Gene Families, Physiology, and Functional Genomics Analyses

    PubMed Central

    Ward, John M.; Mäser, Pascal; Schroeder, Julian I.

    2016-01-01

    Distinct potassium, anion, and calcium channels in the plasma membrane and vacuolar membrane of plant cells have been identified and characterized by patch clamping. Primarily owing to advances in Arabidopsis genetics and genomics, and yeast functional complementation, many of the corresponding genes have been identified. Recent advances in our understanding of ion channel genes that mediate signal transduction and ion transport are discussed here. Some plant ion channels, for example, ALMT and SLAC anion channel subunits, are unique. The majority of plant ion channel families exhibit homology to animal genes; such families include both hyperpolarization-and depolarization-activated Shaker-type potassium channels, CLC chloride transporters/channels, cyclic nucleotide–gated channels, and ionotropic glutamate receptor homologs. These plant ion channels offer unique opportunities to analyze the structural mechanisms and functions of ion channels. Here we review gene families of selected plant ion channel classes and discuss unique structure-function aspects and their physiological roles in plant cell signaling and transport. PMID:18842100

  10. Heterogeneity within Autism Spectrum Disorders: What have We Learned from Neuroimaging Studies?

    PubMed Central

    Lenroot, Rhoshel K.; Yeung, Pui Ka

    2013-01-01

    Autism spectrum disorders (ASD) display significant heterogeneity. Although most neuroimaging studies in ASD have been designed to identify commonalities among affected individuals, rather than differences, some studies have explored variation within ASD. There have been two general types of approaches used for this in the neuroimaging literature to date: comparison of subgroups within ASD, and analyses using dimensional measures to link clinical variation to brain differences. This review focuses on structural and functional magnetic resonance imaging studies that have used these approaches to begin to explore heterogeneity between individuals with ASD. Although this type of data is yet sparse, recognition is growing of the limitations of behaviorally defined categorical diagnoses for understanding neurobiology. Study designs that are more informative regarding the sources of heterogeneity in ASD have the potential to improve our understanding of the neurobiological processes underlying ASD. PMID:24198778

  11. Influence of Assessment Setting on the Results of Functional Analyses of Problem Behavior

    ERIC Educational Resources Information Center

    Lang, Russell; Sigafoos, Jeff; Lancioni, Giulio; Didden, Robert; Rispoli, Mandy

    2010-01-01

    Analogue functional analyses are widely used to identify the operant function of problem behavior in individuals with developmental disabilities. Because problem behavior often occurs across multiple settings (e.g., homes, schools, outpatient clinics), it is important to determine whether the results of functional analyses vary across settings.…

  12. Behavioral Analyses of Taste Function and Ingestion in Rodent Models

    PubMed Central

    Spector, Alan C.

    2015-01-01

    In 1975, at the start of my junior year in college, I took a course on experimental methods in psychology from Dr. James C. Smith, when he was a Visiting Professor at Penn State University. That experience set me on the professional path of studying the neural bases of taste function and ingestion on which I remain to this day. Along the way, I did my graduate work at Florida State University under the tutelage of Jim, I did my postdoctoral training at the University of Pennsylvania under the supervision of Harvey Grill, and I also worked closely with Ralph Norgren, who was at the Penn State Medical College. This article briefly summarizes some of the lessons I learned from my mentors and highlights a few key research findings arising from my privilege of working with gifted students and postdocs. After close to 40 years of being a student of the gustatory system and ingestive behavior, it is still with the greatest conviction that I believe rigorous analysis of behavior is indispensable to any effort seeking to understand brain function. PMID:25892670

  13. Cognitive neuroscience neuroimaging repository for the adult lifespan.

    PubMed

    Razlighi, Qolamreza R; Habeck, Christian; Barulli, Daniel; Stern, Yaakov

    2017-01-01

    With recent advances in neuroimaging technology, it is now possible to image human brain function in vivo, which revolutionized the cognitive neuroscience field. However, like any other newly developed technique, the acquisition of neuroimaging data is costly and logistically challenging. Furthermore, studying human cognition requires acquiring a large amount of neuroimaging data, which might not be feasible to do by every researcher in the field. Here, we describe our group's efforts to acquire one of the largest neuroimaging datasets that aims to investigate the neural substrates of age-related cognitive decline, which will be made available to share with other investigators. Our neuroimaging repository includes up to 14 different functional images for more than 486 subjects across the entire adult lifespan in addition to their 3 structural images. Currently, data from 234 participants have been acquired, including all 14 functional and 3 structural images, which is planned to increased to 375 participants in the next few years. A complete battery of neuropsychological tests was also administered to all participants. The neuroimaging and accompanying psychometric data will be available through an online and easy-to-use data sharing website.

  14. Neuroimaging in Cockayne syndrome.

    PubMed

    Koob, M; Laugel, V; Durand, M; Fothergill, H; Dalloz, C; Sauvanaud, F; Dollfus, H; Namer, I J; Dietemann, J-L

    2010-10-01

    CS is an autosomal recessive multisystem disorder, which is mainly characterized by neurologic and sensory impairment, cachectic dwarfism, and photosensitivity. We describe the neuroimaging features (MR imaging, ¹H-MR spectroscopy, and CT) in the various clinical subtypes of CS from a cohort of genetically and biochemically proved cases. Hypomyelination, calcifications, and brain atrophy were the main imaging features. Calcifications were typically found in the putamen and less often in the cortex and dentate nuclei. Severe progressive atrophy was seen in the supratentorial white matter, the cerebellum, the corpus callosum, and the brain stem. Patients with early-onset disease displayed more severe hypomyelination and prominent calcifications in the sulcal depth of the cerebral cortex, but atrophy was less severe in late-onset patients. On proton MR spectroscopy, lactate was detected and Cho and NAA values were decreased. These combined neuroradiologic findings can help in the differential diagnosis of CS, distinguishing it from other leukoencephalopathies and/or cerebral calcifications in childhood.

  15. Head-related transfer function database and its analyses

    NASA Astrophysics Data System (ADS)

    Xie, Bosun; Zhong, Xiaoli; Rao, Dan; Liang, Zhiqiang

    2007-06-01

    Based on the measurements from 52 Chinese subjects (26 males and 26 females), a high-spatial-resolution head-related transfer function (HRTF) database with corresponding anthropometric parameters is established. By using the database, cues relating to sound source localization, including interaural time difference (ITD), interaural level difference (ILD), and spectral features introduced by pinna, are analyzed. Moreover, the statistical relationship between ITD and anthropometric parameters is estimated. It is proved that the mean values of maximum ITD for male and female are significantly different, so are those for Chinese and western subjects. The difference in ITD is due to the difference in individual anthropometric parameters. It is further proved that the spectral features introduced by pinna strongly depend on individual; while at high frequencies (f ⩾ 5.5 kHz), HRTFs are left-right asymmetric. This work is instructive and helpful for the research on binaural hearing and applications on virtual auditory in future.

  16. Using Pharmabase to perform pharmacological analyses of cell function.

    PubMed

    Smith, Peter J S; Remsen, David

    2006-03-01

    Pharmabase is designed to form a bridge between the molecular dimension of cell transport processes and the functional manipulation of the protein players. It has as its emphasis membrane transport and related pharmacology. Several search and navigation options are available, including membrane transport, disease, and a graphic interface arranged by pathway and cell type. The level of entry to the database can be tailored to the investigator's level of expertise. The final product of Pharmabase is a Compound Record detailing the use and targets of individual compounds. Navigation routes generally fall into hierarchical keys and are cross-referenced. Pharmabase encourages input from its user community. It is maintained by the BioCurrents Research Center, an NIH resource funded through the National Center for Research Resources (NCRR).

  17. [Biodiversity and Function Analyses of BIOLAK Activated Sludge Metagenome].

    PubMed

    Tian, Mei; Liu, Han-hu; Shen, Xin; Zhao, Fang-qing; Chen, Shuai; Yao, Yong-jia

    2015-05-01

    The BIOLAK is a multi-stage activated sludge process, which has been successfully promoted worldwide. However, the biological community and function of the BIOLAK activated sludge ( the core component in the process) have not been reported so far. In this study, taking Lianyungang Dapu Industrial Zone WWTP as an example, a large-scale metagenomic data (428 588 high-quality DNA sequences) of the BIOLAK activated sludge were obtained by means of a new generation of high-throughput sequencing technology. Amazing biodiversity was revealed in the BIOLAK activated sludge, which included 47 phyla, 872 genera and 1351 species. There were 33 phyla identified in the Bacteria domain (289 933 sequences). Proteohacteria was the most abundant phylum (62.54%), followed by Bacteroidetes (11.29%), Nitrospirae ( 5. 65%) and Planctomycetes (4.79%), suggesting that these groups played a key role in the BIOLAK wastewater treatment system. Among the 748 bacterial genera, Nitrospira (5.60%) was the most prevalent genus, which was a key group in the nitrogen cycle. Followed by Gemmatimonas (2.45%), which was an important genus in the biological phosphorus removal process. In Archaea domain (1019 sequences), three phyla and 39 genera were detected. In Eukaryota domain (1055 sequences), 60 genera and 10 phyla were identified, among which Ciliophora was the largest phylum (257 sequences). Meanwhile, 448 viral sequences were detected in the BIOLAK sludge metagenome, which were dominated by bacteriophages. The proportions of nitrogen, aromatic compounds and phosphorus metabolism in the BIOLAK sludge were 2.50%, 2.28% and 1.56%, respectively, which were higher than those in the sludge of United States and Australia. Among four processes of nitrogen metabolism, denitrification-related genes were most abundant (80.81%), followed by ammonification (12.78%), nitrification,(4.38%) and nitrogen fixation (2.04%). In conclusion, the BIOLAK activated sludge had amazing biodiversity, meanwhile

  18. Neuroimaging distinction between neurological and psychiatric disorders†

    PubMed Central

    Crossley, Nicolas A.; Scott, Jessica; Ellison-Wright, Ian; Mechelli, Andrea

    2015-01-01

    Background It is unclear to what extent the traditional distinction between neurological and psychiatric disorders reflects biological differences. Aims To examine neuroimaging evidence for the distinction between neurological and psychiatric disorders. Method We performed an activation likelihood estimation meta-analysis on voxel-based morphometry studies reporting decreased grey matter in 14 neurological and 10 psychiatric disorders, and compared the regional and network-level alterations for these two classes of disease. In addition, we estimated neuroanatomical heterogeneity within and between the two classes. Results Basal ganglia, insula, sensorimotor and temporal cortex showed greater impairment in neurological disorders; whereas cingulate, medial frontal, superior frontal and occipital cortex showed greater impairment in psychiatric disorders. The two classes of disorders affected distinct functional networks. Similarity within classes was higher than between classes; furthermore, similarity within class was higher for neurological than psychiatric disorders. Conclusions From a neuroimaging perspective, neurological and psychiatric disorders represent two distinct classes of disorders. PMID:26045351

  19. Deep learning for neuroimaging: a validation study.

    PubMed

    Plis, Sergey M; Hjelm, Devon R; Salakhutdinov, Ruslan; Allen, Elena A; Bockholt, Henry J; Long, Jeffrey D; Johnson, Hans J; Paulsen, Jane S; Turner, Jessica A; Calhoun, Vince D

    2014-01-01

    Deep learning methods have recently made notable advances in the tasks of classification and representation learning. These tasks are important for brain imaging and neuroscience discovery, making the methods attractive for porting to a neuroimager's toolbox. Success of these methods is, in part, explained by the flexibility of deep learning models. However, this flexibility makes the process of porting to new areas a difficult parameter optimization problem. In this work we demonstrate our results (and feasible parameter ranges) in application of deep learning methods to structural and functional brain imaging data. These methods include deep belief networks and their building block the restricted Boltzmann machine. We also describe a novel constraint-based approach to visualizing high dimensional data. We use it to analyze the effect of parameter choices on data transformations. Our results show that deep learning methods are able to learn physiologically important representations and detect latent relations in neuroimaging data.

  20. Advanced Neuroimaging in Traumatic Brain Injury

    PubMed Central

    Edlow, Brian L.; Wu, Ona

    2013-01-01

    Advances in structural and functional neuroimaging have occurred at a rapid pace over the past two decades. Novel techniques for measuring cerebral blood flow, metabolism, white matter connectivity, and neural network activation have great potential to improve the accuracy of diagnosis and prognosis for patients with traumatic brain injury (TBI), while also providing biomarkers to guide the development of new therapies. Several of these advanced imaging modalities are currently being implemented into clinical practice, whereas others require further development and validation. Ultimately, for advanced neuroimaging techniques to reach their full potential and improve clinical care for the many civilians and military personnel affected by TBI, it is critical for clinicians to understand the applications and methodological limitations of each technique. In this review, we examine recent advances in structural and functional neuroimaging and the potential applications of these techniques to the clinical care of patients with TBI. We also discuss pitfalls and confounders that should be considered when interpreting data from each technique. Finally, given the vast amounts of advanced imaging data that will soon be available to clinicians, we discuss strategies for optimizing data integration, visualization and interpretation. PMID:23361483

  1. Neuroimaging of Wernicke's encephalopathy and Korsakoff's syndrome.

    PubMed

    Jung, Young-Chul; Chanraud, Sandra; Sullivan, Edith V

    2012-06-01

    There is considerable evidence that neuroimaging findings can improve the early diagnosis of Wernicke's encephalopathy (WE) in clinical settings. The most distinctive neuroimaging finding of acute WE are cytotoxic edema and vasogenic edema, which are represented by bilateral symmetric hyperintensity alterations on T2-weighted MR images in the periphery of the third ventricle, periaqueductal area, mammillary bodies and midbrain tectal plate. An initial bout of WE can result in Korsakoff's syndrome (KS), but repeated bouts in conjunction with its typical comorbidity, chronic alcoholism, can result in signs of tissue degeneration in vulnerable brain regions. Chronic abnormalities identified with neuroimaging enable examination of brain damage in living patients with KS and have expanded the understanding of the neuropsychological deficits resulting from thiamine deficiency, alcohol neurotoxicity, and their comorbidity. Brain structure and functional studies indicate that the interactions involving the thalamus, mammillary bodies, hippocampus, frontal lobes, and cerebellum are crucial for memory formation and executive functions, and the interruption of these circuits by WE and chronic alcoholism can contribute substantially to the neuropsychological deficits in KS.

  2. Neuroimaging Studies in Obsessive Compulsive Disorder: A Narrative Review

    PubMed Central

    Parmar, Arpit; Sarkar, Siddharth

    2016-01-01

    Obsessive compulsive disorder (OCD) is a relatively common psychiatric illness with a lifetime prevalence of 2–3% in general population. The pathophysiology of OCD is not yet fully understood, however over the last few decades, evidence for abnormalities of cortico-striatal-thalamic-cortico (CSTC) circuitry in etiopathogenesis of OCD has accumulated. Recent brain imaging techniques have been particularly convincing in suggesting that CSTC circuits are responsible for mediation of OCD symptoms. Neuroimaging studies, especially more recent studies using functional neuroimaging methods have looked for possible changes seen in the brain of patients with OCD, the specificity of the findings (as compared to other psychiatric illnesses) and the effects of treatment (pharmacotherapy/psychotherapy) on such changes were observed. This narrative review discusses the neuroimaging findings seen in patients with OCD with a special focus on relatively more recent neuroimaging modalities such as magnetic resonance spectroscopy and magnetoencephalography. PMID:27833219

  3. Sports concussions and aging: a neuroimaging investigation.

    PubMed

    Tremblay, Sebastien; De Beaumont, Louis; Henry, Luke C; Boulanger, Yvan; Evans, Alan C; Bourgouin, Pierre; Poirier, Judes; Théoret, Hugo; Lassonde, Maryse

    2013-05-01

    Recent epidemiological and experimental studies suggest a link between cognitive decline in late adulthood and sports concussions sustained in early adulthood. In order to provide the first in vivo neuroanatomical evidence of this relation, the present study probes the neuroimaging profile of former athletes with concussions in relation to cognition. Former athletes who sustained their last sports concussion >3 decades prior to testing were compared with those with no history of traumatic brain injury. Participants underwent quantitative neuroimaging (optimized voxel-based morphometry [VBM], hippocampal volume, and cortical thickness), proton magnetic resonance spectroscopy ((1)H MRS; medial temporal lobes and prefrontal cortices), and neuropsychological testing, and they were genotyped for APOE polymorphisms. Relative to controls, former athletes with concussions exhibited: 1) Abnormal enlargement of the lateral ventricles, 2) cortical thinning in regions more vulnerable to the aging process, 3) various neurometabolic anomalies found across regions of interest, 4) episodic memory and verbal fluency decline. The cognitive deficits correlated with neuroimaging findings in concussed participants. This study unveiled brain anomalies in otherwise healthy former athletes with concussions and associated those manifestations to the long-term detrimental effects of sports concussion on cognitive function. Findings from this study highlight patterns of decline often associated with abnormal aging.

  4. Understanding the minds of others: A neuroimaging meta-analysis.

    PubMed

    Molenberghs, Pascal; Johnson, Halle; Henry, Julie D; Mattingley, Jason B

    2016-06-01

    Theory of mind (ToM) is an important skill that refers broadly to the capacity to understand the mental states of others. A large number of neuroimaging studies have focused on identifying the functional brain regions involved in ToM, but many important questions remain with respect to the neural networks implicated in specific types of ToM tasks. In the present study, we conducted a series of activation likelihood estimation (ALE) meta-analyses on 144 datasets (involving 3150 participants) to address these questions. The ALE results revealed common regions shared across all ToM tasks and broader task parameters, but also some important dissociations. In terms of commonalities, consistent activation was identified in the medial prefrontal cortex and bilateral temporoparietal junction. On the other hand, ALE contrast analyses on our dataset, as well as meta-analytic connectivity modelling (MACM) analyses on the BrainMap database, indicated that different types of ToM tasks reliably elicit activity in unique brain areas. Our findings provide the most accurate picture to date of the neural networks that underpin ToM function.

  5. Loss-of-function analyses defines vital and redundant functions of the Plasmodium rhomboid protease family.

    PubMed

    Lin, Jing-Wen; Meireles, Patrícia; Prudêncio, Miguel; Engelmann, Sabine; Annoura, Takeshi; Sajid, Mohammed; Chevalley-Maurel, Séverine; Ramesar, Jai; Nahar, Carolin; Avramut, Cristina M C; Koster, Abraham J; Matuschewski, Kai; Waters, Andrew P; Janse, Chris J; Mair, Gunnar R; Khan, Shahid M

    2013-04-01

    Rhomboid-like proteases cleave membrane-anchored proteins within their transmembrane domains. In apicomplexan parasites substrates include molecules that function in parasite motility and host cell invasion. While two Plasmodium rhomboids, ROM1 and ROM4, have been examined, the roles of the remaining six rhomboids during the malaria parasite's life cycle are unknown. We present systematic gene deletion analyses of all eight Plasmodium rhomboid-like proteins as a means to discover stage-specific phenotypes and potential functions in the rodent malaria model, P. berghei. Four rhomboids (ROM4, 6, 7 and 8) are refractory to gene deletion, suggesting an essential role during asexual blood stage development. In contrast ROM1, 3, 9 and 10 were dispensable for blood stage development and exhibited no, subtle or severe defects in mosquito or liver development. Parasites lacking ROM9 and ROM10 showed no major phenotypic defects. Parasites lacking ROM1 presented a delay in blood stage patency following liver infection, but in contrast to a previous study blood stage parasites had similar growth and virulence characteristics as wild type parasites. Parasites lacking ROM3 in mosquitoes readily established oocysts but failed to produce sporozoites. ROM3 is the first apicomplexan rhomboid identified to play a vital role in sporogony.

  6. Structural and functional analyses of human cerebral cortex using a surface-based atlas

    NASA Technical Reports Server (NTRS)

    Van Essen, D. C.; Drury, H. A.

    1997-01-01

    We have analyzed the geometry, geography, and functional organization of human cerebral cortex using surface reconstructions and cortical flat maps of the left and right hemispheres generated from a digital atlas (the Visible Man). The total surface area of the reconstructed Visible Man neocortex is 1570 cm2 (both hemispheres), approximately 70% of which is buried in sulci. By linking the Visible Man cerebrum to the Talairach stereotaxic coordinate space, the locations of activation foci reported in neuroimaging studies can be readily visualized in relation to the cortical surface. The associated spatial uncertainty was empirically shown to have a radius in three dimensions of approximately 10 mm. Application of this approach to studies of visual cortex reveals the overall patterns of activation associated with different aspects of visual function and the relationship of these patterns to topographically organized visual areas. Our analysis supports a distinction between an anterior region in ventral occipito-temporal cortex that is selectively involved in form processing and a more posterior region (in or near areas VP and V4v) involved in both form and color processing. Foci associated with motion processing are mainly concentrated in a region along the occipito-temporal junction, the ventral portion of which overlaps with foci also implicated in form processing. Comparisons between flat maps of human and macaque monkey cerebral cortex indicate significant differences as well as many similarities in the relative sizes and positions of cortical regions known or suspected to be homologous in the two species.

  7. Auditory verbal hallucinations: neuroimaging and treatment.

    PubMed

    Bohlken, M M; Hugdahl, K; Sommer, I E C

    2017-01-01

    Auditory verbal hallucinations (AVH) are a frequently occurring phenomenon in the general population and are considered a psychotic symptom when presented in the context of a psychiatric disorder. Neuroimaging literature has shown that AVH are subserved by a variety of alterations in brain structure and function, which primarily concentrate around brain regions associated with the processing of auditory verbal stimuli and with executive control functions. However, the direction of association between AVH and brain function remains equivocal in certain research areas and needs to be carefully reviewed and interpreted. When AVH have significant impact on daily functioning, several efficacious treatments can be attempted such as antipsychotic medication, brain stimulation and cognitive-behavioural therapy. Interestingly, the neural correlates of these treatments largely overlap with brain regions involved in AVH. This suggests that the efficacy of treatment corresponds to a normalization of AVH-related brain activity. In this selected review, we give a compact yet comprehensive overview of the structural and functional neuroimaging literature on AVH, with a special focus on the neural correlates of efficacious treatment.

  8. Source counting in MEG neuroimaging

    NASA Astrophysics Data System (ADS)

    Lei, Tianhu; Dell, John; Magee, Ralphy; Roberts, Timothy P. L.

    2009-02-01

    Magnetoencephalography (MEG) is a multi-channel, functional imaging technique. It measures the magnetic field produced by the primary electric currents inside the brain via a sensor array composed of a large number of superconducting quantum interference devices. The measurements are then used to estimate the locations, strengths, and orientations of these electric currents. This magnetic source imaging technique encompasses a great variety of signal processing and modeling techniques which include Inverse problem, MUltiple SIgnal Classification (MUSIC), Beamforming (BF), and Independent Component Analysis (ICA) method. A key problem with Inverse problem, MUSIC and ICA methods is that the number of sources must be detected a priori. Although BF method scans the source space on a point-to-point basis, the selection of peaks as sources, however, is finally made by subjective thresholding. In practice expert data analysts often select results based on physiological plausibility. This paper presents an eigenstructure approach for the source number detection in MEG neuroimaging. By sorting eigenvalues of the estimated covariance matrix of the acquired MEG data, the measured data space is partitioned into the signal and noise subspaces. The partition is implemented by utilizing information theoretic criteria. The order of the signal subspace gives an estimate of the number of sources. The approach does not refer to any model or hypothesis, hence, is an entirely data-led operation. It possesses clear physical interpretation and efficient computation procedure. The theoretical derivation of this method and the results obtained by using the real MEG data are included to demonstrates their agreement and the promise of the proposed approach.

  9. Applications of Optical Neuroimaging in Usability Research

    PubMed Central

    Hill, Audrey P.; Bohil, Corey J.

    2016-01-01

    FEATURE AT A GLANCE In this article we review recent and potential applications of optical neuroimaging to human factors and usability research. We focus specifically on functional near-infrared spectroscopy (fNIRS) because of its cost-effectiveness and ease of implementation. Researchers have used fNIRS to assess a range of psychological phenomena relevant to human factors, such as cognitive workload, attention, motor activity, and more. It offers the opportunity to measure hemodynamic correlates of mental activity during task completion in human factors and usability studies. We also consider some limitations and future research directions. PMID:28286404

  10. Validating Trial-Based Functional Analyses in Mainstream Primary School Classrooms

    ERIC Educational Resources Information Center

    Austin, Jennifer L.; Groves, Emily A.; Reynish, Lisa C.; Francis, Laura L.

    2015-01-01

    There is growing evidence to support the use of trial-based functional analyses, particularly in classroom settings. However, there currently are no evaluations of this procedure with typically developing children. Furthermore, it is possible that refinements may be needed to adapt trial-based analyses to mainstream classrooms. This study was…

  11. Neuroimaging the interaction of mind and metabolism in humans

    PubMed Central

    D’Agostino, Alexandra E.; Small, Dana M.

    2012-01-01

    Hormonal and metabolic signals interact with neural circuits orchestrating behavior to guide food intake. Neuroimaging techniques such as functional magnetic resonance imaging (fMRI) enable the identification of where in the brain particular mental processes like desire, satiety and pleasure occur. Once these neural circuits are described it then becomes possible to determine how metabolic and hormonal signals can alter brain response to influence psychological states and decision-making processes to guide intake. Here, we provide an overview of the contributions of functional neuroimaging to the understanding of how subjective and neural responses to food and food cues interact with metabolic/hormonal factors. PMID:24024114

  12. Scanning the horizon: towards transparent and reproducible neuroimaging research.

    PubMed

    Poldrack, Russell A; Baker, Chris I; Durnez, Joke; Gorgolewski, Krzysztof J; Matthews, Paul M; Munafò, Marcus R; Nichols, Thomas E; Poline, Jean-Baptiste; Vul, Edward; Yarkoni, Tal

    2017-02-01

    Functional neuroimaging techniques have transformed our ability to probe the neurobiological basis of behaviour and are increasingly being applied by the wider neuroscience community. However, concerns have recently been raised that the conclusions that are drawn from some human neuroimaging studies are either spurious or not generalizable. Problems such as low statistical power, flexibility in data analysis, software errors and a lack of direct replication apply to many fields, but perhaps particularly to functional MRI. Here, we discuss these problems, outline current and suggested best practices, and describe how we think the field should evolve to produce the most meaningful and reliable answers to neuroscientific questions.

  13. Neuroimaging of Parkinson’s Disease: Expanding views

    PubMed Central

    Weingarten, Carol P.; Sundman, Mark H.; Hickey, Patrick; Chen, Nankuei

    2015-01-01

    Advances in molecular and structural and functional neuroimaging are rapidly expanding the complexity of neurobiological understanding of Parkinson’s disease (PD). This review article begins with an introduction to PD neurobiology as a foundation for interpreting neuroimaging findings that may further lead to more integrated and comprehensive understanding of PD. Diverse areas of PD neuroimaging are then reviewed and summarized, including positron emission tomography, single photon emission computed tomography, magnetic resonance spectroscopy and imaging, transcranial sonography, magnetoencephalography, and multimodal imaging, with focus on human studies published over the last five years. These included studies on differential diagnosis, co-morbidity, genetic and prodromal PD, and treatments from L-DOPA to brain stimulation approaches, transplantation and gene therapies. Overall, neuroimaging has shown that PD is a neurodegenerative disorder involving many neurotransmitters, brain regions, structural and functional connections, and neurocognitive systems. A broad neurobiological understanding of PD will be essential for translational efforts to develop better treatments and preventive strategies. Many questions remain and we conclude with some suggestions for future directions of neuroimaging of PD. PMID:26409344

  14. Machine learning for neuroimaging with scikit-learn.

    PubMed

    Abraham, Alexandre; Pedregosa, Fabian; Eickenberg, Michael; Gervais, Philippe; Mueller, Andreas; Kossaifi, Jean; Gramfort, Alexandre; Thirion, Bertrand; Varoquaux, Gaël

    2014-01-01

    Statistical machine learning methods are increasingly used for neuroimaging data analysis. Their main virtue is their ability to model high-dimensional datasets, e.g., multivariate analysis of activation images or resting-state time series. Supervised learning is typically used in decoding or encoding settings to relate brain images to behavioral or clinical observations, while unsupervised learning can uncover hidden structures in sets of images (e.g., resting state functional MRI) or find sub-populations in large cohorts. By considering different functional neuroimaging applications, we illustrate how scikit-learn, a Python machine learning library, can be used to perform some key analysis steps. Scikit-learn contains a very large set of statistical learning algorithms, both supervised and unsupervised, and its application to neuroimaging data provides a versatile tool to study the brain.

  15. A processual model for functional analyses of carcinogenesis in the prospective cohort design.

    PubMed

    Lund, Eiliv; Plancade, Sandra; Nuel, Gregory; Bøvelstad, Hege; Thalabard, Jean-Christophe

    2015-10-01

    Traditionally, the prospective design has been chosen for risk factor analyses of lifestyle and cancer using mainly estimation by survival analysis methods. With new technologies, epidemiologists can expand their prospective studies to include functional genomics given either as transcriptomics, mRNA and microRNA, or epigenetics in blood or other biological materials. The novel functional analyses should not be assessed using classical survival analyses since the main goal is not risk estimation, but the analysis of functional genomics as part of the dynamic carcinogenic process over time, i.e., a "processual" approach. In the risk factor model, time to event is analysed as a function of exposure variables known at start of follow-up (fixed covariates) or changing over the follow-up period (time-dependent covariates). In the processual model, transcriptomics or epigenetics is considered as functions of time and exposures. The success of this novel approach depends on the development of new statistical methods with the capacity of describing and analysing the time-dependent curves or trajectories for tens of thousands of genes simultaneously. This approach also focuses on multilevel or integrative analyses introducing novel statistical methods in epidemiology. The processual approach as part of systems epidemiology might represent in a near future an alternative to human in vitro studies using human biological material for understanding the mechanisms and pathways involved in carcinogenesis.

  16. Kidney function changes with aging in adults: comparison between cross-sectional and longitudinal data analyses in renal function assessment.

    PubMed

    Chung, Sang M; Lee, David J; Hand, Austin; Young, Philip; Vaidyanathan, Jayabharathi; Sahajwalla, Chandrahas

    2015-12-01

    The study evaluated whether the renal function decline rate per year with age in adults varies based on two primary statistical analyses: cross-section (CS), using one observation per subject, and longitudinal (LT), using multiple observations per subject over time. A total of 16628 records (3946 subjects; age range 30-92 years) of creatinine clearance and relevant demographic data were used. On average, four samples per subject were collected for up to 2364 days (mean: 793 days). A simple linear regression and random coefficient models were selected for CS and LT analyses, respectively. The renal function decline rates per year were 1.33 and 0.95 ml/min/year for CS and LT analyses, respectively, and were slower when the repeated individual measurements were considered. The study confirms that rates are different based on statistical analyses, and that a statistically robust longitudinal model with a proper sampling design provides reliable individual as well as population estimates of the renal function decline rates per year with age in adults. In conclusion, our findings indicated that one should be cautious in interpreting the renal function decline rate with aging information because its estimation was highly dependent on the statistical analyses. From our analyses, a population longitudinal analysis (e.g. random coefficient model) is recommended if individualization is critical, such as a dose adjustment based on renal function during a chronic therapy.

  17. LSTGEE: longitudinal analysis of neuroimaging data

    NASA Astrophysics Data System (ADS)

    Li, Yimei; Zhu, Hongtu; Chen, Yasheng; An, Hongyu; Gilmore, John; Lin, Weili; Shen, Dinggang

    2009-02-01

    Longitudinal imaging studies are essential to understanding the neural development of neuropsychiatric disorders, substance use disorders, and normal brain. Using appropriate image processing and statistical tools to analyze the imaging, behavioral, and clinical data is critical for optimally exploring and interpreting the findings from those imaging studies. However, the existing imaging processing and statistical methods for analyzing imaging longitudinal measures are primarily developed for cross-sectional neuroimaging studies. The simple use of these cross-sectional tools to longitudinal imaging studies will significantly decrease the statistical power of longitudinal studies in detecting subtle changes of imaging measures and the causal role of time-dependent covariate in disease process. The main objective of this paper is to develop longitudinal statistics toolbox, called LSTGEE, for the analysis of neuroimaging data from longitudinal studies. We develop generalized estimating equations for jointly modeling imaging measures with behavioral and clinical variables from longitudinal studies. We develop a test procedure based on a score test statistic and a resampling method to test linear hypotheses of unknown parameters, such as associations between brain structure and function and covariates of interest, such as IQ, age, gene, diagnostic groups, and severity of disease. We demonstrate the application of our statistical methods to the detection of the changes of the fractional anisotropy across time in a longitudinal neonate study. Particularly, our results demonstrate that the use of longitudinal statistics can dramatically increase the statistical power in detecting the changes of neuroimaging measures. The proposed approach can be applied to longitudinal data with multiple outcomes and accommodate incomplete and unbalanced data, i.e., subjects with different number of measurements.

  18. The Co-evolution of Neuroimaging and Psychiatric Neurosurgery

    PubMed Central

    Dyster, Timothy G.; Mikell, Charles B.; Sheth, Sameer A.

    2016-01-01

    The role of neuroimaging in psychiatric neurosurgery has evolved significantly throughout the field’s history. Psychiatric neurosurgery initially developed without the benefit of information provided by modern imaging modalities, and thus lesion targets were selected based on contemporary theories of frontal lobe dysfunction in psychiatric disease. However, by the end of the 20th century, the availability of structural and functional magnetic resonance imaging (fMRI) allowed for the development of mechanistic theories attempting to explain the anatamofunctional basis of these disorders, as well as the efficacy of stereotactic neuromodulatory treatments. Neuroimaging now plays a central and ever-expanding role in the neurosurgical management of psychiatric disorders, by influencing the determination of surgical candidates, allowing individualized surgical targeting and planning, and identifying network-level changes in the brain following surgery. In this review, we aim to describe the coevolution of psychiatric neurosurgery and neuroimaging, including ways in which neuroimaging has proved useful in elucidating the therapeutic mechanisms of neuromodulatory procedures. We focus on ablative over stimulation-based procedures given their historical precedence and the greater opportunity they afford for post-operative re-imaging, but also discuss important contributions from the deep brain stimulation (DBS) literature. We conclude with a discussion of how neuroimaging will transition the field of psychiatric neurosurgery into the era of precision medicine. PMID:27445706

  19. Use of latency to problem behavior to evaluate demands for inclusion in functional analyses.

    PubMed

    Call, Nathan A; Pabico, Ryan S; Lomas, Joanna E

    2009-01-01

    Few direct-assessment procedures are designed to identify potential negative reinforcers (e.g., including demands in the escape condition of functional analyses). Two participants were systematically exposed to a series of demands nominated by caregivers as potential negative reinforcers. Sessions ended following the first instance of problem behavior, and a hierarchy of demand aversiveness was created based on the latency to the first problem behavior. Subsequent functional analyses confirmed the predictive value of the hierarchy, with shorter latency demands consistently producing more differentiated functional analysis outcomes.

  20. USE OF LATENCY TO PROBLEM BEHAVIOR TO EVALUATE DEMANDS FOR INCLUSION IN FUNCTIONAL ANALYSES

    PubMed Central

    Call, Nathan A; Pabico, Ryan S; Lomas, Joanna E

    2009-01-01

    Few direct-assessment procedures are designed to identify potential negative reinforcers (e.g., including demands in the escape condition of functional analyses). Two participants were systematically exposed to a series of demands nominated by caregivers as potential negative reinforcers. Sessions ended following the first instance of problem behavior, and a hierarchy of demand aversiveness was created based on the latency to the first problem behavior. Subsequent functional analyses confirmed the predictive value of the hierarchy, with shorter latency demands consistently producing more differentiated functional analysis outcomes. PMID:20190935

  1. Neuroimaging of the Periaqueductal Gray: State of the Field

    PubMed Central

    Linnman, Clas; Moulton, Eric A.; Barmettler, Gabi; Becerra, Lino; Borsook, David

    2011-01-01

    This review and meta-analysis aims at summarizing and integrating the human neuroimaging studies that report periaqueductal gray (PAG) involvement; 250 original manuscripts on human neuroimaging of the PAG were identified. A narrative review and meta-analysis using activation likelihood estimates is included. Behaviors covered include pain and pain modulation, anxiety, bladder and bowel function and autonomic regulation. Methods include structural and functional magnetic resonance imaging, functional connectivity measures, diffusion weighted imaging and positron emission tomography. Human neuroimaging studies in healthy and clinical populations largely confirm the animal literature indicating that the PAG is involved in homeostatic regulation of salient functions such as pain, anxiety and autonomic function. Methodological concerns in the current literature, including resolution constraints, imaging artifacts and imprecise neuroanatomical labeling are discussed, and future directions are proposed. A general conclusion is that PAG neuroimaging is a field with enormous potential to translate animal data onto human behaviors, but with some growing pains that can and need to be addressed in order to add to our understanding of the neurobiology of this key region. PMID:22197740

  2. Image analysis and statistical inference in neuroimaging with R.

    PubMed

    Tabelow, K; Clayden, J D; de Micheaux, P Lafaye; Polzehl, J; Schmid, V J; Whitcher, B

    2011-04-15

    R is a language and environment for statistical computing and graphics. It can be considered an alternative implementation of the S language developed in the 1970s and 1980s for data analysis and graphics (Becker and Chambers, 1984; Becker et al., 1988). The R language is part of the GNU project and offers versions that compile and run on almost every major operating system currently available. We highlight several R packages built specifically for the analysis of neuroimaging data in the context of functional MRI, diffusion tensor imaging, and dynamic contrast-enhanced MRI. We review their methodology and give an overview of their capabilities for neuroimaging. In addition we summarize some of the current activities in the area of neuroimaging software development in R.

  3. Neuroethics, neuroimaging, and disorders of consciousness: promise or peril?

    PubMed

    Fins, Joseph J

    2011-01-01

    The advent of powerful neuroimaging tools such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) has begun to redefine how we diagnose, define, and understand disorders of consciousness such as the vegetative and minimally conscious states. In my paper, I review how research using these methods is both elucidating these brain states and creating diagnostic dilemmas related to their classification as the specificity and sensitivity of traditional behavior-based assessments are weighed against sensitive but not yet fully validated neuroimaging data. I also consider how these methods are being studied as potential communication vectors for therapeutic use in subjects who heretofore have been thought to be unresponsive or minimally conscious. I conclude by considering the ethical challenges posed by novel diagnostic and therapeutic neuroimaging applications and contextualize these scientific developments against the broader needs of patients and families touched by severe brain injury.

  4. Physiological fluctuations in white matter are increased in Alzheimer's disease and correlate with neuroimaging and cognitive biomarkers.

    PubMed

    Makedonov, Ilia; Chen, J Jean; Masellis, Mario; MacIntosh, Bradley J

    2016-01-01

    The objective of this study was to determine whether physiological fluctuations in white matter (PFWM) on resting-state functional magnetic resonance images could be used as an index of neurodegeneration and Alzheimer's disease (AD). Using resting-state functional magnetic resonance image data from participants in the Alzheimer's Disease Neuroimaging Initiative, PFWM was compared across cohorts: cognitively healthy, mild cognitive impairment, or probable AD. Secondary regression analyses were conducted between PFWM and neuroimaging, cognitive, and cerebrospinal fluid biomarkers. There was an effect of cohort on PFWM (t = 5.08, degree of freedom [df] = 424, p < 5.7 × 10(-7)), after accounting for nuisance effects from head displacement and global signal (t > 6.16). From the neuroimaging data, PFWM was associated with glucose metabolism (t = -2.93, df = 96, p = 0.004) but not ventricular volume (p < 0.49) or hippocampal volume (p > 0.44). From the cognitive data, PFWM was associated with composite memory (t = -3.24, df = 149, p = 0.0015) but not executive function (p > 0.21). PFWM was not associated with cerebrospinal fluid biomarkers. In one final omnibus model to explain PFWM (n = 124), glucose metabolism (p = 0.04) and cohort (p = 0.008) remained significant, as were global and head motion root-mean-square terms, whereas memory was not (p = 0.64). PFWM likely reflects end-arteriole intracranial pulsatility effects that may provide additional diagnostic potential in the context of AD neurodegeneration.

  5. Use of a latency-based demand assessment to identify potential demands for functional analyses.

    PubMed

    Call, Nathan A; Miller, Sarah J; Mintz, Joslyn Cynkus; Mevers, Joanna Lomas; Scheithauer, Mindy C; Eshelman, Julie E; Beavers, Gracie A

    2016-12-01

    Unlike potential tangible positive reinforcers, which are typically identified for inclusion in functional analyses empirically using preference assessments, demands are most often selected arbitrarily or based on caregiver report. The present study evaluated the use of a demand assessment with 12 participants who exhibited escape-maintained problem behavior. Participants were exposed to 10 demands, with aversiveness measured by average latency to the first instance of problem behavior. In subsequent functional analyses, results of a demand condition that included the demand with the shortest latency to problem behavior resulted in identification of an escape function for 11 of the participants. In contrast, a demand condition that included the demand with the longest latency resulted in identification of an escape function for only 5 participants. The implication of these findings is that for the remaining 7 participants, selection of the demand for the functional analysis without using the results of the demand assessment could have produced a false-negative finding.

  6. Dynamic model for the tissue concentration and oxygen saturation of hemoglobin in relation to blood volume, flow velocity, and oxygen consumption: Implications for functional neuroimaging and coherent hemodynamics spectroscopy (CHS)

    PubMed Central

    Fantini, Sergio

    2013-01-01

    This article presents a dynamic model that quantifies the temporal evolution of the concentration and oxygen saturation of hemoglobin in tissue, as determined by time-varying hemodynamic and metabolic parameters: blood volume, flow velocity, and oxygen consumption. This multi-compartment model determines separate contributions from arterioles, capillaries, and venules that comprise the tissue microvasculature, and treats them as a complete network, without making assumptions on the details of the architecture and morphology of the microvascular bed. A key parameter in the model is the effective blood transit time through the capillaries and its associated probability of oxygen release from hemoglobin to tissue, as described by a rate constant for oxygen diffusion. The solution of the model in the time domain predicts the signals measured by hemodynamic-based neuroimaging techniques such as functional near-infrared spectroscopy (fNIRS) and functional magnetic resonance imaging (fMRI) in response to brain activation. In the frequency domain, the model yields an analytical solution based on a phasor representation that provides a framework for quantitative spectroscopy of coherent hemodynamic oscillations. I term this novel technique coherent hemodynamics spectroscopy (CHS), and this article describes how it can be used for the assessment of cerebral autoregulation and the study of hemodynamic oscillations resulting from a variety of periodic physiological challenges, brain activation protocols, or physical maneuvers. PMID:23583744

  7. How Shakespeare tempests the brain: neuroimaging insights.

    PubMed

    Keidel, James L; Davis, Philip M; Gonzalez-Diaz, Victorina; Martin, Clara D; Thierry, Guillaume

    2013-04-01

    Shakespeare made extensive use of the functional shift (FS), a rhetorical device involving a change in the grammatical status of words, e.g., using nouns as verbs. Previous work using event-related brain potentials showed how FS triggers a surprise effect inviting mental re-evaluation, seemingly independent of semantic processing. Here, we used functional magnetic resonance imaging to investigate brain activation in participants making judgements on the semantic relationship between sentences -some containing a Shakespearean FS- and subsequently presented words. Behavioural performance in the semantic decision task was high and unaffected by sentence type. However, neuroimaging results showed that sentences featuring FS elicited significant activation beyond regions classically activated by typical language tasks, including the left caudate nucleus, the right inferior frontal gyrus and the right inferior temporal gyrus. These findings show how Shakespeare's grammatical exploration forces the listener to take a more active role in integrating the meaning of what is said.

  8. An Overview of Multimodal Neuroimaging Using Nanoprobes

    PubMed Central

    Sridhar, Sriram; Mishra, Sachin; Gulyás, Miklós; Padmanabhan, Parasuraman; Gulyás, Balázs

    2017-01-01

    Nanomaterials have gained tremendous significance as contrast agents for both anatomical and functional preclinical bio-imaging. Contrary to conventional medical practices, molecular imaging plays an important role in exploring the affected cells, thus providing precision medical solutions. It has been observed that incorporating nanoprobes improves the overall efficacy of the diagnosis and treatment processes. These nano-agents and tracers are therefore often incorporated into preclinical therapeutic and diagnostic applications. Multimodal imaging approaches are well equipped with nanoprobes to explore neurological disorders, as they can display more than one type of characteristic in molecular imaging. Multimodal imaging systems are explored by researchers as they can provide both anatomical and functional details of tumors and affected tissues. In this review, we present the state-of-the-art research concerning multimodal imaging systems and nanoprobes for neuroimaging applications. PMID:28157157

  9. The teen brain: insights from neuroimaging.

    PubMed

    Giedd, Jay N

    2008-04-01

    Few parents of a teenager are surprised to hear that the brain of a 16-year-old is different from the brain of an 8-year-old. Yet to pin down these differences in a rigorous scientific way has been elusive. Magnetic resonance imaging, with the capacity to provide exquisitely accurate quantifications of brain anatomy and physiology without the use of ionizing radiation, has launched a new era of adolescent neuroscience. Longitudinal studies of subjects from ages 3-30 years demonstrate a general pattern of childhood peaks of gray matter followed by adolescent declines, functional and structural increases in connectivity and integrative processing, and a changing balance between limbic/subcortical and frontal lobe functions, extending well into young adulthood. Although overinterpretation and premature application of neuroimaging findings for diagnostic purposes remains a risk, converging data from multiple imaging modalities is beginning to elucidate the implications of these brain changes on cognition, emotion, and behavior.

  10. Crucial role of detailed function, task, timeline, link and human vulnerability analyses in HRA

    SciTech Connect

    Ryan, T.G.; Haney, L.N.; Ostrom, L.T.

    1992-10-01

    This paper addresses one major cause for large uncertainties in human reliability analysis (HRA) results, that is, an absence of detailed function, task, timeline, link and human vulnerability analyses. All too often this crucial step in the HRA process is done in a cursory fashion using word of mouth or written procedures which themselves may incompletely or inaccurately represent the human action sequences and human error vulnerabilities being analyzed. The paper examines the potential contributions these detailed analyses can make in achieving quantitative and qualitative HRA results which are: (1) creditable, that is, minimize uncertainty, (2) auditable, that is, systematically linking quantitative results and qualitative information from which the results are derived, (3) capable of supporting root cause analyses on human reliability factors determined to be major contributors to risk, and (4) capable of repeated measures and being combined with similar results from other analyses to examine HRA issues transcending individual systems and facilities. Based on experience analyzing test and commercial nuclear reactors, and medical applications of nuclear technology, an iterative process is suggested for doing detailed function, task, timeline, link and human vulnerability analyses using documentation reviews, open-ended and structured interviews, direct observations, and group techniques. Finally, the paper concludes that detailed analyses done in this manner by knowledgeable human factors practitioners, can contribute significantly to the credibility, auditability, causal factor analysis, and combining goals of the HRA.

  11. Further Evaluation of Leisure Items in the Attention Condition of Functional Analyses

    PubMed Central

    Roscoe, Eileen M; Carreau, Abbey; MacDonald, Jackie; Pence, Sacha T

    2008-01-01

    Research suggests that including leisure items in the attention condition of a functional analysis may produce engagement that masks sensitivity to attention. In this study, 4 individuals' initial functional analyses indicated that behavior was maintained by nonsocial variables (n  =  3) or by attention (n  =  1). A preference assessment was used to identify items for subsequent functional analyses. Four conditions were compared, attention with and without leisure items and control with and without leisure items. Following this, either high- or low-preference items were included in the attention condition. Problem behavior was more probable during the attention condition when no leisure items or low-preference items were included, and lower levels of problem behavior were observed during the attention condition when high-preference leisure items were included. These findings suggest how preferred items may hinder detection of behavioral function. PMID:18816974

  12. Neuroimaging of child abuse: a critical review

    PubMed Central

    Hart, Heledd; Rubia, Katya

    2012-01-01

    Childhood maltreatment is a stressor that can lead to the development of behavior problems and affect brain structure and function. This review summarizes the current evidence for the effects of childhood maltreatment on behavior, cognition and the brain in adults and children. Neuropsychological studies suggest an association between child abuse and deficits in IQ, memory, working memory, attention, response inhibition and emotion discrimination. Structural neuroimaging studies provide evidence for deficits in brain volume, gray and white matter of several regions, most prominently the dorsolateral and ventromedial prefrontal cortex but also hippocampus, amygdala, and corpus callosum (CC). Diffusion tensor imaging (DTI) studies show evidence for deficits in structural interregional connectivity between these areas, suggesting neural network abnormalities. Functional imaging studies support this evidence by reporting atypical activation in the same brain regions during response inhibition, working memory, and emotion processing. There are, however, several limitations of the abuse research literature which are discussed, most prominently the lack of control for co-morbid psychiatric disorders, which make it difficult to disentangle which of the above effects are due to maltreatment, the associated psychiatric conditions or a combination or interaction between both. Overall, the better controlled studies that show a direct correlation between childhood abuse and brain measures suggest that the most prominent deficits associated with early childhood abuse are in the function and structure of lateral and ventromedial fronto-limbic brain areas and networks that mediate behavioral and affect control. Future, large scale multimodal neuroimaging studies in medication-naïve subjects, however, are needed that control for psychiatric co-morbidities in order to elucidate the structural and functional brain sequelae that are associated with early environmental adversity

  13. Neuroimaging in Psychiatric Pharmacogenetics Research: The Promise and Pitfalls

    PubMed Central

    Falcone, Mary; Smith, Ryan M; Chenoweth, Meghan J; Kumar Bhattacharjee, Abesh; Kelsoe, John R; Tyndale, Rachel F; Lerman, Caryn

    2013-01-01

    The integration of research on neuroimaging and pharmacogenetics holds promise for improving treatment for neuropsychiatric conditions. Neuroimaging may provide a more sensitive early measure of treatment response in genetically defined patient groups, and could facilitate development of novel therapies based on an improved understanding of pathogenic mechanisms underlying pharmacogenetic associations. This review summarizes progress in efforts to incorporate neuroimaging into genetics and treatment research on major psychiatric disorders, such as schizophrenia, major depressive disorder, bipolar disorder, attention-deficit/hyperactivity disorder, and addiction. Methodological challenges include: performing genetic analyses in small study populations used in imaging studies; inclusion of patients with psychiatric comorbidities; and the extensive variability across studies in neuroimaging protocols, neurobehavioral task probes, and analytic strategies. Moreover, few studies use pharmacogenetic designs that permit testing of genotype × drug effects. As a result of these limitations, few findings have been fully replicated. Future studies that pre-screen participants for genetic variants selected a priori based on drug metabolism and targets have the greatest potential to advance the science and practice of psychiatric treatment. PMID:23793356

  14. Leisure Items as Controls in the Attention Condition of Functional Analyses

    ERIC Educational Resources Information Center

    McCord, Brandon E.; Neef, Nancy A.

    2005-01-01

    Leisure items (e.g., games, toys) are commonly made available as controls during attention conditions of functional analyses (Ringdahl, Winborn, Andelman, & Kitsukawa, 2002). However, Ringdahl et al. raised questions about this practice. This paper reviews research that supports and conflicts with the inclusion of leisure items as controls,…

  15. Use of Latency to Problem Behavior to Evaluate Demands for Inclusion in Functional Analyses

    ERIC Educational Resources Information Center

    Call, Nathan A.; Pabico, Ryan S.; Lomas, Joanna E.

    2009-01-01

    Few direct-assessment procedures are designed to identify potential negative reinforcers (e.g., including demands in the escape condition of functional analyses). Two participants were systematically exposed to a series of demands nominated by caregivers as potential negative reinforcers. Sessions ended following the first instance of problem…

  16. Functional analyses of the digestive ß-Glucosidase of Formosan Subterranean Termites (Coptotermes formosanus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The research was to elucidate the function of the ß-glucosidase of Formosan subterranean termites in vitro and in vivo. Quantitative RT-PCR analyses indicated that the gene transcript was relatively more abundant in the foraging worker caste than in other castes and salivary glands were the major ex...

  17. A Comparison of Outcomes from Descriptive and Functional Analyses of Problem Behavior

    ERIC Educational Resources Information Center

    Thompson, Rachel H.; Iwata, Brian A.

    2007-01-01

    We compared results of descriptive and functional analyses of problem behavior for 12 participants whose descriptive data have been reported previously (Thompson & Iwata, 2001). Results indicated that in only 3 of the 12 cases was problem behavior maintained by the consequence observed most frequently during the descriptive analysis. Attention was…

  18. Play versus Alone Conditions as Controls during Functional Analyses of Self-Injurious Escape Behavior.

    ERIC Educational Resources Information Center

    Kahng, SungWoo; Iwata, Brian A.

    1998-01-01

    A study compared effects of continuous reinforcement (play) and alone conditions as controls during functional analyses for 66 individuals whose self-injurious behavior (SIB) was maintained by escape. SIB was lower during both control conditions than it was during the test (demand) condition. SIB was lowest during the alone condition. (Author/CR)

  19. Analysing Symbolic Expressions in Secondary School Chemistry: Their Functions and Implications for Pedagogy

    ERIC Educational Resources Information Center

    Liu, Yu; Taber, Keith S.

    2016-01-01

    Symbolic expressions are essential resources for producing knowledge, yet they are a source of learning difficulties in chemistry education. This study aims to employ social semiotics to analyse the symbolic representation of chemistry from two complementary perspectives, referred to here as contextual (i.e., historical) and functional. First, the…

  20. The Matching Criterion Purification for Differential Item Functioning Analyses in a Large-Scale Assessment

    ERIC Educational Resources Information Center

    Lee, HyeSun; Geisinger, Kurt F.

    2016-01-01

    The current study investigated the impact of matching criterion purification on the accuracy of differential item functioning (DIF) detection in large-scale assessments. The three matching approaches for DIF analyses (block-level matching, pooled booklet matching, and equated pooled booklet matching) were employed with the Mantel-Haenszel…

  1. Using Additional Analyses to Clarify the Functions of Problem Behavior: An Analysis of Two Cases

    ERIC Educational Resources Information Center

    Payne, Steven W.; Dozier, Claudia L.; Neidert, Pamela L.; Jowett, Erica S.; Newquist, Matthew H.

    2014-01-01

    Functional analyses (FA) have proven useful for identifying contingencies that influence problem behavior. Research has shown that some problem behavior may only occur in specific contexts or be influenced by multiple or idiosyncratic variables. When these contexts or sources of influence are not assessed in an FA, further assessment may be…

  2. Autism spectrum disorder: does neuroimaging support the DSM-5 proposal for a symptom dyad? A systematic review of functional magnetic resonance imaging and diffusion tensor imaging studies.

    PubMed

    Pina-Camacho, Laura; Villero, Sonia; Fraguas, David; Boada, Leticia; Janssen, Joost; Navas-Sánchez, Francisco J; Mayoral, Maria; Llorente, Cloe; Arango, Celso; Parellada, Mara

    2012-07-01

    A systematic review of 208 studies comprising functional magnetic resonance imaging and diffusion tensor imaging data in patients with 'autism spectrum disorder' (ASD) was conducted, in order to determine whether these data support the forthcoming DSM-5 proposal of a social communication and behavioral symptom dyad. Studies consistently reported abnormal function and structure of fronto-temporal and limbic networks with social and pragmatic language deficits, of temporo-parieto-occipital networks with syntactic-semantic language deficits, and of fronto-striato-cerebellar networks with repetitive behaviors and restricted interests in ASD patients. Therefore, this review partially supports the DSM-5 proposal for the ASD dyad.

  3. [Side effects analyses in consideration of renal function for S-1-administered patients].

    PubMed

    Iwai, Mina; Kimura, Michio; Yoshimura, Tomoaki; Yasuda, Tadashi

    2011-06-01

    Although many analyses of S-1 side effects are reported, there are no reports where the analyses of side effects were performed in consideration of renal function, which is an important index of medication dose. Therefore, we investigated side effects in consideration of renal function. The subjects were 163 patients administered S-1 at the Department of Surgery of Ogaki Municipal Hospital, between October 2008 and December 2009. The frequency and severity of side effects were high and serious in the groupwhose creatinine clearance was low. A significant difference was observed among 3 groups with regard to thrombocytopenia and dehydration. In conclusion, we think that pharmacists must take renal function into consideration when administering medication, to keepclose medicinal guidance, and to actively observe progress.

  4. Autism Spectrum Disorder: Does Neuroimaging Support the DSM-5 Proposal for a Symptom Dyad? A Systematic Review of Functional Magnetic Resonance Imaging and Diffusion Tensor Imaging Studies

    ERIC Educational Resources Information Center

    Pina-Camacho, Laura; Villero, Sonia; Fraguas, David; Boada, Leticia; Janssen, Joost; Navas-Sanchez, Francisco J.; Mayoral, Maria; Llorente, Cloe; Arango, Celso; Parellada, Mara

    2012-01-01

    A systematic review of 208 studies comprising functional magnetic resonance imaging and diffusion tensor imaging data in patients with "autism spectrum disorder" (ASD) was conducted, in order to determine whether these data support the forthcoming DSM-5 proposal of a social communication and behavioral symptom dyad. Studies consistently reported…

  5. Neuroimaging Week: A Novel, Engaging, and Effective Curriculum for Teaching Neuroimaging to Junior Psychiatric Residents

    ERIC Educational Resources Information Center

    Downar, Jonathan; Krizova, Adriana; Ghaffar, Omar; Zaretsky, Ari

    2010-01-01

    Objective: Neuroimaging techniques are increasingly important in psychiatric research and clinical practice, but few postgraduate psychiatry programs offer formal training in neuroimaging. To address this need, the authors developed a course to prepare psychiatric residents to use neuroimaging techniques effectively in independent practice.…

  6. Neuroimaging for drug addiction and related behaviors

    SciTech Connect

    Parvaz M. A.; Parvaz, M.A.; Alia-Klein, N.; Woicik,P.A.; Volkow, N.D.; Goldstein, R.Z.

    2011-10-01

    In this review, we highlight the role of neuroimaging techniques in studying the emotional and cognitive-behavioral components of the addiction syndrome by focusing on the neural substrates subserving them. The phenomenology of drug addiction can be characterized by a recurrent pattern of subjective experiences that includes drug intoxication, craving, bingeing, and withdrawal with the cycle culminating in a persistent preoccupation with obtaining, consuming, and recovering from the drug. In the past two decades, imaging studies of drug addiction have demonstrated deficits in brain circuits related to reward and impulsivity. The current review focuses on studies employing positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and electroencephalography (EEG) to investigate these behaviors in drug-addicted human populations. We begin with a brief account of drug addiction followed by a technical account of each of these imaging modalities. We then discuss how these techniques have uniquely contributed to a deeper understanding of addictive behaviors.

  7. Neuroimaging for drug addiction and related behaviors

    PubMed Central

    Parvaz, Muhammad A.; Alia-Klein, Nelly; Woicik, Patricia A.; Volkow, Nora D.; Goldstein, Rita Z.

    2012-01-01

    In this review, we highlight the role of neuroimaging techniques in studying the emotional and cognitive-behavioral components of the addiction syndrome by focusing on the neural substrates subserving them. The phenomenology of drug addiction can be characterized by a recurrent pattern of subjective experiences that includes drug intoxication, craving, bingeing, and withdrawal with the cycle culminating in a persistent preoccupation with obtaining, consuming, and recovering from the drug. In the past two decades, imaging studies of drug addiction have demonstrated deficits in brain circuits related to reward and impulsivity. The current review focuses on studies employing positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and electroencephalography (EEG) to investigate these behaviors in drug-addicted human populations. We begin with a brief account of drug addiction followed by a technical account of each of these imaging modalities. We then discuss how these techniques have uniquely contributed to a deeper understanding of addictive behaviors. PMID:22117165

  8. The experience of art: insights from neuroimaging.

    PubMed

    Nadal, Marcos

    2013-01-01

    The experience of art is a complex one. It emerges from the interaction of multiple cognitive and affective processes. Neuropsychological and neuroimaging studies are revealing the broadly distributed network of brain regions upon which it relies. This network can be divided into three functional components: (i) prefrontal, parietal, and temporal cortical regions support evaluative judgment, attentional processing, and memory retrieval; (ii) the reward circuit, including cortical, subcortical regions, and some of its regulators, is involved in the generation of pleasurable feelings and emotions, and the valuation and anticipation of reward; and (iii) attentional modulation of activity in low-, mid-, and high-level cortical sensory regions enhances the perceptual processing of certain features, relations, locations, or objects. Understanding how these regions act in concert to produce unique and moving art experiences and determining the impact of personal and cultural meaning and context on this network the biological foundation of the experience of art--remain future challenges.

  9. Overlapping prefrontal systems involved in cognitive and emotional processing in euthymic bipolar disorder and following sleep deprivation: A review of functional neuroimaging studies

    PubMed Central

    McKenna, Benjamin S; Eyler, Lisa T

    2013-01-01

    Prefrontal cortex (PFC) mediated cognitive and emotional processing deficits in bipolar disorder lead to functional limitations even during periods of mood stability. Alterations of sleep and circadian functioning are well-documented in bipolar disorder, but there is little research directly examining the mechanistic role of sleep and/or circadian rhythms in the observed cognitive and emotional processing deficits. We systematically review the cognitive and emotional processing deficits reliant upon PFC functioning of euthymic patients with bipolar disorder and in healthy individuals deprived of sleep. The evidence from two parallel lines of investigation suggests that sleep and circadian rhythms may be involved in the cognitive and emotional processing deficits seen in bipolar disorder through overlapping neurobiological systems. We discuss current models of bipolar highlighting the PFC-limbic connections and discuss inclusion of sleep-related mechanisms. Sleep and circadian dysfunction is a core feature of bipolar disorder and models of neurobiological abnormalities should incorporate chronobiological measures. Further research into the role of sleep and circadian rhythms in cognition and emotional processing in bipolar disorder is warranted. PMID:22926687

  10. Perception of affective and linguistic prosody: an ALE meta-analysis of neuroimaging studies.

    PubMed

    Belyk, Michel; Brown, Steven

    2014-09-01

    Prosody refers to the melodic and rhythmic aspects of speech. Two forms of prosody are typically distinguished: 'affective prosody' refers to the expression of emotion in speech, whereas 'linguistic prosody' relates to the intonation of sentences, including the specification of focus within sentences and stress within polysyllabic words. While these two processes are united by their use of vocal pitch modulation, they are functionally distinct. In order to examine the localization and lateralization of speech prosody in the brain, we performed two voxel-based meta-analyses of neuroimaging studies of the perception of affective and linguistic prosody. There was substantial sharing of brain activations between analyses, particularly in right-hemisphere auditory areas. However, a major point of divergence was observed in the inferior frontal gyrus: affective prosody was more likely to activate Brodmann area 47, while linguistic prosody was more likely to activate the ventral part of area 44.

  11. Three brain collections for comparative neuroanatomy and neuroimaging.

    PubMed

    Zilles, Karl; Amunts, Katrin; Smaers, Jeroen B

    2011-05-01

    In the context of increasing extinction rates and the potential loss of essential evolutionary biological and anthropological information, it is an important task to support efforts to prepare, preserve, and curate collections of histological brain sections; to disseminate information on such collections in the neuroscience community; and to make the collections publicly available. This review emphasizes the importance of complete, serially sectioned human brains of different ontogenetic stages as well as those of adult and old human individuals for neurobiological and medical research. Such histological sections enable microstructural analyses and anatomical evaluations of functional and structural neuroimaging data, for example, based on magnetic resonance imaging. Here, this review provides the first detailed and updated account of the content of the Stephan, Zilles, and Zilles-Amunts collections, which consist of serially sectioned and cell body- and myelin-stained histological preparations. Finally, this review will give an overview of past and recent research using these collections to increase our understanding of the detailed patterns of divergent brain evolution in primates as well as of the structural organization of the human brain.

  12. Classification and Functional Analyses of Putative Conserved Proteins from Chlamydophila pneumoniae CWL029.

    PubMed

    Khan, Shama; Shahbaaz, Mohd; Bisetty, Krishna; Ahmad, Faizan; Hassan, Md Imtaiyaz

    2017-03-01

    Chlamydophila pneumoniae, a Gram-negative bacterium belongs to the family Chlamydiaceae, is known to cause community-acquired pneumonia and bronchitis. There is a need for genomic analyses of C. pneumoniae as its chronic infections result in reactive airway disease, lung cancer and asthma. Recent advancement in the sequencing techniques led to the generation of large genomic data. In order to utilize these data, sequence-based function predictions were used for annotating the uncharacterized genes. The genome of C. pneumoniae encodes 1052 proteins, which include a group of 366 functionally uncharacterized proteins, known as "hypothetical proteins" (HPs). Functions of these HPs were predicted by utilizing an integrated approach that combines varieties of bioinformatics tools. The functions of 142 proteins were successfully predicted and categorized into different classes of enzymes, transport proteins, binding proteins and virulence factors. Among these functionally annotated HPs, we were able to identify 12 virulent HPs. Furthermore, the HP with the highest virulence score was subjected to molecular dynamics (MD) simulations to better understand their dynamical behavior in explicit water conditions. These analyses could be utilized for an in-depth understanding of virulence mechanism. The functional knowledge of these proteins could be useful in drug design and discovery process of infections caused by C. pneumoniae.

  13. Neuroimaging findings in late-onset schizophrenia and bipolar disorder.

    PubMed

    Hahn, Changtae; Lim, Hyun Kook; Lee, Chang Uk

    2014-03-01

    In recent years, there has been an increasing interest in late-onset mental disorders. Among them, geriatric schizophrenia and bipolar disorder are significant health care risks and major causes of disability. We discussed whether late-onset schizophrenia (LOS) and late-onset bipolar (LOB) disorder can be a separate entity from early-onset schizophrenia (EOS) and early-onset bipolar (EOB) disorder in a subset of late-life schizophrenia or late-life bipolar disorder through neuroimaging studies. A literature search for imaging studies of LOS or LOB was performed in the PubMed database. Search terms used were "(imaging OR MRI OR CT OR SPECT OR DTI OR PET OR fMRI) AND (schizophrenia or bipolar disorder) AND late onset." Articles that were published in English before October 2013 were included. There were a few neuroimaging studies assessing whether LOS and LOB had different disease-specific neural substrates compared with EOS and EOB. These researches mainly observed volumetric differences in specific brain regions, white matter hyperintensities, diffusion tensor imaging, or functional neuroimaging to explore the differences between LOS and LOB and EOS and EOB. The aim of this review was to highlight the neural substrates involved in LOS and LOB through neuroimaging studies. The exploration of neuroanatomical markers may be the key to the understanding of underlying neurobiology in LOS and LOB.

  14. Individual-based analyses reveal limited functional overlap in a coral reef fish community.

    PubMed

    Brandl, Simon J; Bellwood, David R

    2014-05-01

    Detailed knowledge of a species' functional niche is crucial for the study of ecological communities and processes. The extent of niche overlap, functional redundancy and functional complementarity is of particular importance if we are to understand ecosystem processes and their vulnerability to disturbances. Coral reefs are among the most threatened marine systems, and anthropogenic activity is changing the functional composition of reefs. The loss of herbivorous fishes is particularly concerning as the removal of algae is crucial for the growth and survival of corals. Yet, the foraging patterns of the various herbivorous fish species are poorly understood. Using a multidimensional framework, we present novel individual-based analyses of species' realized functional niches, which we apply to a herbivorous coral reef fish community. In calculating niche volumes for 21 species, based on their microhabitat utilization patterns during foraging, and computing functional overlaps, we provide a measurement of functional redundancy or complementarity. Complementarity is the inverse of redundancy and is defined as less than 50% overlap in niche volumes. The analyses reveal extensive complementarity with an average functional overlap of just 15.2%. Furthermore, the analyses divide herbivorous reef fishes into two broad groups. The first group (predominantly surgeonfishes and parrotfishes) comprises species feeding on exposed surfaces and predominantly open reef matrix or sandy substrata, resulting in small niche volumes and extensive complementarity. In contrast, the second group consists of species (predominantly rabbitfishes) that feed over a wider range of microhabitats, penetrating the reef matrix to exploit concealed surfaces of various substratum types. These species show high variation among individuals, leading to large niche volumes, more overlap and less complementarity. These results may have crucial consequences for our understanding of herbivorous processes on

  15. The Decoding Toolbox (TDT): a versatile software package for multivariate analyses of functional imaging data

    PubMed Central

    Hebart, Martin N.; Görgen, Kai; Haynes, John-Dylan

    2015-01-01

    The multivariate analysis of brain signals has recently sparked a great amount of interest, yet accessible and versatile tools to carry out decoding analyses are scarce. Here we introduce The Decoding Toolbox (TDT) which represents a user-friendly, powerful and flexible package for multivariate analysis of functional brain imaging data. TDT is written in Matlab and equipped with an interface to the widely used brain data analysis package SPM. The toolbox allows running fast whole-brain analyses, region-of-interest analyses and searchlight analyses, using machine learning classifiers, pattern correlation analysis, or representational similarity analysis. It offers automatic creation and visualization of diverse cross-validation schemes, feature scaling, nested parameter selection, a variety of feature selection methods, multiclass capabilities, and pattern reconstruction from classifier weights. While basic users can implement a generic analysis in one line of code, advanced users can extend the toolbox to their needs or exploit the structure to combine it with external high-performance classification toolboxes. The toolbox comes with an example data set which can be used to try out the various analysis methods. Taken together, TDT offers a promising option for researchers who want to employ multivariate analyses of brain activity patterns. PMID:25610393

  16. Intergenerational Neuroimaging of Human Brain Circuitry.

    PubMed

    Ho, Tiffany C; Sanders, Stephan J; Gotlib, Ian H; Hoeft, Fumiko

    2016-10-01

    Neuroscientists are increasingly using advanced neuroimaging methods to elucidate the intergenerational transmission of human brain circuitry. This new line of work promises to shed light on the ontogeny of complex behavioral traits, including psychiatric disorders, and possible mechanisms of transmission. Here we highlight recent intergenerational neuroimaging studies and provide recommendations for future work.

  17. Neuroimaging and Research into Second Language Acquisition

    ERIC Educational Resources Information Center

    Sabourin, Laura

    2009-01-01

    Neuroimaging techniques are becoming not only more and more sophisticated but are also coming to be increasingly accessible to researchers. One thing that one should take note of is the potential of neuroimaging research within second language acquisition (SLA) to contribute to issues pertaining to the plasticity of the adult brain and to general…

  18. The neural network for tool-related cognition: An activation likelihood estimation meta-analysis of 70 neuroimaging contrasts

    PubMed Central

    Ishibashi, Ryo; Pobric, Gorana; Saito, Satoru; Lambon Ralph, Matthew A.

    2016-01-01

    ABSTRACT The ability to recognize and use a variety of tools is an intriguing human cognitive function. Multiple neuroimaging studies have investigated neural activations with various types of tool-related tasks. In the present paper, we reviewed tool-related neural activations reported in 70 contrasts from 56 neuroimaging studies and performed a series of activation likelihood estimation (ALE) meta-analyses to identify tool-related cortical circuits dedicated either to general tool knowledge or to task-specific processes. The results indicate the following: (a) Common, task-general processing regions for tools are located in the left inferior parietal lobule (IPL) and ventral premotor cortex; and (b) task-specific regions are located in superior parietal lobule (SPL) and dorsal premotor area for imagining/executing actions with tools and in bilateral occipito-temporal cortex for recognizing/naming tools. The roles of these regions in task-general and task-specific activities are discussed with reference to evidence from neuropsychology, experimental psychology and other neuroimaging studies. PMID:27362967

  19. The Generality of Interview-Informed Functional Analyses: Systematic Replications in School and Home.

    PubMed

    Santiago, Joana L; Hanley, Gregory P; Moore, Keira; Jin, C Sandy

    2016-03-01

    Behavioral interventions preceded by a functional analysis have been proven efficacious in treating severe problem behavior associated with autism. There is, however, a lack of research showing socially validated outcomes when assessment and treatment procedures are conducted by ecologically relevant individuals in typical settings. In this study, interview-informed functional analyses and skill-based treatments (Hanley et al. in J Appl Behav Anal 47:16-36, 2014) were applied by a teacher and home-based provider in the classroom and home of two children with autism. The function-based treatments resulted in socially validated reductions in severe problem behavior (self-injury, aggression, property destruction). Furthermore, skills lacking in baseline-functional communication, denial and delay tolerance, and compliance with adult instructions-occurred with regularity following intervention. The generality and costs of the process are discussed.

  20. A simple tool for neuroimaging data sharing

    PubMed Central

    Haselgrove, Christian; Poline, Jean-Baptiste; Kennedy, David N.

    2014-01-01

    Data sharing is becoming increasingly common, but despite encouragement and facilitation by funding agencies, journals, and some research efforts, most neuroimaging data acquired today is still not shared due to political, financial, social, and technical barriers to sharing data that remain. In particular, technical solutions are few for researchers that are not a part of larger efforts with dedicated sharing infrastructures, and social barriers such as the time commitment required to share can keep data from becoming publicly available. We present a system for sharing neuroimaging data, designed to be simple to use and to provide benefit to the data provider. The system consists of a server at the International Neuroinformatics Coordinating Facility (INCF) and user tools for uploading data to the server. The primary design principle for the user tools is ease of use: the user identifies a directory containing Digital Imaging and Communications in Medicine (DICOM) data, provides their INCF Portal authentication, and provides identifiers for the subject and imaging session. The user tool anonymizes the data and sends it to the server. The server then runs quality control routines on the data, and the data and the quality control reports are made public. The user retains control of the data and may change the sharing policy as they need. The result is that in a few minutes of the user’s time, DICOM data can be anonymized and made publicly available, and an initial quality control assessment can be performed on the data. The system is currently functional, and user tools and access to the public image database are available at http://xnat.incf.org/. PMID:24904398

  1. Sharing brain mapping statistical results with the neuroimaging data model

    PubMed Central

    Maumet, Camille; Auer, Tibor; Bowring, Alexander; Chen, Gang; Das, Samir; Flandin, Guillaume; Ghosh, Satrajit; Glatard, Tristan; Gorgolewski, Krzysztof J.; Helmer, Karl G.; Jenkinson, Mark; Keator, David B.; Nichols, B. Nolan; Poline, Jean-Baptiste; Reynolds, Richard; Sochat, Vanessa; Turner, Jessica; Nichols, Thomas E.

    2016-01-01

    Only a tiny fraction of the data and metadata produced by an fMRI study is finally conveyed to the community. This lack of transparency not only hinders the reproducibility of neuroimaging results but also impairs future meta-analyses. In this work we introduce NIDM-Results, a format specification providing a machine-readable description of neuroimaging statistical results along with key image data summarising the experiment. NIDM-Results provides a unified representation of mass univariate analyses including a level of detail consistent with available best practices. This standardized representation allows authors to relay methods and results in a platform-independent regularized format that is not tied to a particular neuroimaging software package. Tools are available to export NIDM-Result graphs and associated files from the widely used SPM and FSL software packages, and the NeuroVault repository can import NIDM-Results archives. The specification is publically available at: http://nidm.nidash.org/specs/nidm-results.html. PMID:27922621

  2. Sharing brain mapping statistical results with the neuroimaging data model.

    PubMed

    Maumet, Camille; Auer, Tibor; Bowring, Alexander; Chen, Gang; Das, Samir; Flandin, Guillaume; Ghosh, Satrajit; Glatard, Tristan; Gorgolewski, Krzysztof J; Helmer, Karl G; Jenkinson, Mark; Keator, David B; Nichols, B Nolan; Poline, Jean-Baptiste; Reynolds, Richard; Sochat, Vanessa; Turner, Jessica; Nichols, Thomas E

    2016-12-06

    Only a tiny fraction of the data and metadata produced by an fMRI study is finally conveyed to the community. This lack of transparency not only hinders the reproducibility of neuroimaging results but also impairs future meta-analyses. In this work we introduce NIDM-Results, a format specification providing a machine-readable description of neuroimaging statistical results along with key image data summarising the experiment. NIDM-Results provides a unified representation of mass univariate analyses including a level of detail consistent with available best practices. This standardized representation allows authors to relay methods and results in a platform-independent regularized format that is not tied to a particular neuroimaging software package. Tools are available to export NIDM-Result graphs and associated files from the widely used SPM and FSL software packages, and the NeuroVault repository can import NIDM-Results archives. The specification is publically available at: http://nidm.nidash.org/specs/nidm-results.html.

  3. Genetic imaging consortium for addiction medicine: From neuroimaging to genes.

    PubMed

    Mackey, Scott; Kan, Kees-Jan; Chaarani, Bader; Alia-Klein, Nelly; Batalla, Albert; Brooks, Samantha; Cousijn, Janna; Dagher, Alain; de Ruiter, Michiel; Desrivieres, Sylvane; Feldstein Ewing, Sarah W; Goldstein, Rita Z; Goudriaan, Anna E; Heitzeg, Mary M; Hutchison, Kent; Li, Chiang-Shan R; London, Edythe D; Lorenzetti, Valentina; Luijten, Maartje; Martin-Santos, Rocio; Morales, Angelica M; Paulus, Martin P; Paus, Tomas; Pearlson, Godfrey; Schluter, Renée; Momenan, Reza; Schmaal, Lianne; Schumann, Gunter; Sinha, Rajita; Sjoerds, Zsuzsika; Stein, Dan J; Stein, Elliot A; Solowij, Nadia; Tapert, Susan; Uhlmann, Anne; Veltman, Dick; van Holst, Ruth; Walter, Henrik; Wright, Margaret J; Yucel, Murat; Yurgelun-Todd, Deborah; Hibar, Derrek P; Jahanshad, Neda; Thompson, Paul M; Glahn, David C; Garavan, Hugh; Conrod, Patricia

    2016-01-01

    Since the sample size of a typical neuroimaging study lacks sufficient statistical power to explore unknown genomic associations with brain phenotypes, several international genetic imaging consortia have been organized in recent years to pool data across sites. The challenges and achievements of these consortia are considered here with the goal of leveraging these resources to study addiction. The authors of this review have joined together to form an Addiction working group within the framework of the ENIGMA project, a meta-analytic approach to multisite genetic imaging data. Collectively, the Addiction working group possesses neuroimaging and genomic data obtained from over 10,000 subjects. The deadline for contributing data to the first round of analyses occurred at the beginning of May 2015. The studies performed on this data should significantly impact our understanding of the genetic and neurobiological basis of addiction.

  4. Nonhuman primate positron emission tomography neuroimaging in drug abuse research.

    PubMed

    Howell, Leonard Lee; Murnane, Kevin Sean

    2011-05-01

    Positron emission tomography (PET) neuroimaging in nonhuman primates has led to significant advances in our current understanding of the neurobiology and treatment of stimulant addiction in humans. PET neuroimaging has defined the in vivo biodistribution and pharmacokinetics of abused drugs and related these findings to the time course of behavioral effects associated with their addictive properties. With novel radiotracers and enhanced resolution, PET neuroimaging techniques have also characterized in vivo drug interactions with specific protein targets in the brain, including neurotransmitter receptors and transporters. In vivo determinations of cerebral blood flow and metabolism have localized brain circuits implicated in the effects of abused drugs and drug-associated stimuli. Moreover, determinations of the predisposing factors to chronic drug use and long-term neurobiological consequences of chronic drug use, such as potential neurotoxicity, have led to novel insights regarding the pathology and treatment of drug addiction. However, similar approaches clearly need to be extended to drug classes other than stimulants. Although dopaminergic systems have been extensively studied, other neurotransmitter systems known to play a critical role in the pharmacological effects of abused drugs have been largely ignored in nonhuman primate PET neuroimaging. Finally, the study of brain activation with PET neuroimaging has been replaced in humans mostly by functional magnetic resonance imaging (fMRI). There has been some success in implementing pharmacological fMRI in awake nonhuman primates. Nevertheless, the unique versatility of PET imaging will continue to complement the systems-level strengths of fMRI, especially in the context of nonhuman primate drug abuse research.

  5. An empirical comparison of different approaches for combining multimodal neuroimaging data with support vector machine.

    PubMed

    Pettersson-Yeo, William; Benetti, Stefania; Marquand, Andre F; Joules, Richard; Catani, Marco; Williams, Steve C R; Allen, Paul; McGuire, Philip; Mechelli, Andrea

    2014-01-01

    In the pursuit of clinical utility, neuroimaging researchers of psychiatric and neurological illness are increasingly using analyses, such as support vector machine, that allow inference at the single-subject level. Recent studies employing single-modality data, however, suggest that classification accuracies must be improved for such utility to be realized. One possible solution is to integrate different data types to provide a single combined output classification; either by generating a single decision function based on an integrated kernel matrix, or, by creating an ensemble of multiple single modality classifiers and integrating their predictions. Here, we describe four integrative approaches: (1) an un-weighted sum of kernels, (2) multi-kernel learning, (3) prediction averaging, and (4) majority voting, and compare their ability to enhance classification accuracy relative to the best single-modality classification accuracy. We achieve this by integrating structural, functional, and diffusion tensor magnetic resonance imaging data, in order to compare ultra-high risk (n = 19), first episode psychosis (n = 19) and healthy control subjects (n = 23). Our results show that (i) whilst integration can enhance classification accuracy by up to 13%, the frequency of such instances may be limited, (ii) where classification can be enhanced, simple methods may yield greater increases relative to more computationally complex alternatives, and, (iii) the potential for classification enhancement is highly influenced by the specific diagnostic comparison under consideration. In conclusion, our findings suggest that for moderately sized clinical neuroimaging datasets, combining different imaging modalities in a data-driven manner is no "magic bullet" for increasing classification accuracy. However, it remains possible that this conclusion is dependent on the use of neuroimaging modalities that had little, or no, complementary information to offer one another, and that the

  6. Functional Gene Networks: R/Bioc package to generate and analyse gene networks derived from functional enrichment and clustering

    PubMed Central

    Aibar, Sara; Fontanillo, Celia; Droste, Conrad; De Las Rivas, Javier

    2015-01-01

    Summary: Functional Gene Networks (FGNet) is an R/Bioconductor package that generates gene networks derived from the results of functional enrichment analysis (FEA) and annotation clustering. The sets of genes enriched with specific biological terms (obtained from a FEA platform) are transformed into a network by establishing links between genes based on common functional annotations and common clusters. The network provides a new view of FEA results revealing gene modules with similar functions and genes that are related to multiple functions. In addition to building the functional network, FGNet analyses the similarity between the groups of genes and provides a distance heatmap and a bipartite network of functionally overlapping genes. The application includes an interface to directly perform FEA queries using different external tools: DAVID, GeneTerm Linker, TopGO or GAGE; and a graphical interface to facilitate the use. Availability and implementation: FGNet is available in Bioconductor, including a tutorial. URL: http://bioconductor.org/packages/release/bioc/html/FGNet.html Contact: jrivas@usal.es Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25600944

  7. Functional Analyses of the Crohn’s Disease Risk Gene LACC1

    PubMed Central

    Vesterlund, Liselotte; Bonfiglio, Ferdinando; Mazzurana, Luca; Cordeddu, Lina; Schepis, Danika; Mjösberg, Jenny; Ruhrmann, Sabrina; Fabbri, Alessia; Vukojevic, Vladana; Percipalle, Piergiorgio; Salomons, Florian A.; Laurencikiene, Jurga; Törkvist, Leif; Halfvarson, Jonas; D’Amato, Mauro

    2016-01-01

    Background Genetic variation in the Laccase (multicopper oxidoreductase) domain-containing 1 (LACC1) gene has been shown to affect the risk of Crohn’s disease, leprosy and, more recently, ulcerative colitis and juvenile idiopathic arthritis. LACC1 function appears to promote fatty-acid oxidation, with concomitant inflammasome activation, reactive oxygen species production, and anti-bacterial responses in macrophages. We sought to contribute to elucidating LACC1 biological function by extensive characterization of its expression in human tissues and cells, and through preliminary analyses of the regulatory mechanisms driving such expression. Methods We implemented Western blot, quantitative real-time PCR, immunofluorescence microscopy, and flow cytometry analyses to investigate fatty acid metabolism-immune nexus (FAMIN; the LACC1 encoded protein) expression in subcellular compartments, cell lines and relevant human tissues. Gene-set enrichment analyses were performed to initially investigate modulatory mechanisms of LACC1 expression. A small-interference RNA knockdown in vitro model system was used to study the effect of FAMIN depletion on peroxisome function. Results FAMIN expression was detected in macrophage-differentiated THP-1 cells and several human tissues, being highest in neutrophils, monocytes/macrophages, myeloid and plasmacytoid dendritic cells among peripheral blood cells. Subcellular co-localization was exclusively confined to peroxisomes, with some additional positivity for organelle endomembrane structures. LACC1 co-expression signatures were enriched for genes involved in peroxisome proliferator-activated receptors (PPAR) signaling pathways, and PPAR ligands downregulated FAMIN expression in in vitro model systems. Conclusion FAMIN is a peroxisome-associated protein with primary role(s) in macrophages and other immune cells, where its metabolic functions may be modulated by PPAR signaling events. However, the precise molecular mechanisms through

  8. Functional and structural analyses of behavior: approaches leading to reduced use of punishment procedures?

    PubMed

    Axelrod, S

    1987-01-01

    A common approach to dealing with the serious misbehaviors of handicapped individuals is to use punishment procedures. Although punishment techniques are often effective, many claim that their use is restrictive. Emerging approaches for dealing with inappropriate behavior are to conduct a functional or structural analysis of behavior. These approaches allow practitioners to isolate and manipulate the factors responsible for aberrant behaviors. Such analyses may reveal that a maladaptive behavior results in adult attention, is associated with demand situations, or provides reinforcing sensory feedback. In each case corrective procedures relevant to the function of the inappropriate behavior or its associated stimuli, can be applied. In some cases the analysis will reveal alternative approaches to the use of punishment procedures. In other cases it may not. Presently, there have been relatively few examples of the functional and structural analysis approaches; results thus far, however, have been encouraging.

  9. Protein function prediction by massive integration of evolutionary analyses and multiple data sources

    PubMed Central

    2013-01-01

    Background Accurate protein function annotation is a severe bottleneck when utilizing the deluge of high-throughput, next generation sequencing data. Keeping database annotations up-to-date has become a major scientific challenge that requires the development of reliable automatic predictors of protein function. The CAFA experiment provided a unique opportunity to undertake comprehensive 'blind testing' of many diverse approaches for automated function prediction. We report on the methodology we used for this challenge and on the lessons we learnt. Methods Our method integrates into a single framework a wide variety of biological information sources, encompassing sequence, gene expression and protein-protein interaction data, as well as annotations in UniProt entries. The methodology transfers functional categories based on the results from complementary homology-based and feature-based analyses. We generated the final molecular function and biological process assignments by combining the initial predictions in a probabilistic manner, which takes into account the Gene Ontology hierarchical structure. Results We propose a novel scoring function called COmbined Graph-Information Content similarity (COGIC) score for the comparison of predicted functional categories and benchmark data. We demonstrate that our integrative approach provides increased scope and accuracy over both the component methods and the naïve predictors. In line with previous studies, we find that molecular function predictions are more accurate than biological process assignments. Conclusions Overall, the results indicate that there is considerable room for improvement in the field. It still remains for the community to invest a great deal of effort to make automated function prediction a useful and routine component in the toolbox of life scientists. As already witnessed in other areas, community-wide blind testing experiments will be pivotal in establishing standards for the evaluation of

  10. Meta-Analysis in Human Neuroimaging: Computational Modeling of Large-Scale Databases

    PubMed Central

    Fox, Peter T.; Lancaster, Jack L.; Laird, Angela R.; Eickhoff, Simon B.

    2016-01-01

    Spatial normalization—applying standardized coordinates as anatomical addresses within a reference space—was introduced to human neuroimaging research nearly 30 years ago. Over these three decades, an impressive series of methodological advances have adopted, extended, and popularized this standard. Collectively, this work has generated a methodologically coherent literature of unprecedented rigor, size, and scope. Large-scale online databases have compiled these observations and their associated meta-data, stimulating the development of meta-analytic methods to exploit this expanding corpus. Coordinate-based meta-analytic methods have emerged and evolved in rigor and utility. Early methods computed cross-study consensus, in a manner roughly comparable to traditional (nonimaging) meta-analysis. Recent advances now compute coactivation-based connectivity, connectivity-based functional parcellation, and complex network models powered from data sets representing tens of thousands of subjects. Meta-analyses of human neuroimaging data in large-scale databases now stand at the forefront of computational neurobiology. PMID:25032500

  11. Sleep neuroimaging and models of consciousness.

    PubMed

    Tagliazucchi, Enzo; Behrens, Marion; Laufs, Helmut

    2013-01-01

    Human deep sleep is characterized by reduced sensory activity, responsiveness to stimuli, and conscious awareness. Given its ubiquity and reversible nature, it represents an attractive paradigm to study the neural changes which accompany the loss of consciousness in humans. In particular, the deepest stages of sleep can serve as an empirical test for the predictions of theoretical models relating the phenomenology of consciousness with underlying neural activity. A relatively recent shift of attention from the analysis of evoked responses toward spontaneous (or "resting state") activity has taken place in the neuroimaging community, together with the development of tools suitable to study distributed functional interactions. In this review we focus on recent functional Magnetic Resonance Imaging (fMRI) studies of spontaneous activity during sleep and their relationship with theoretical models for human consciousness generation, considering the global workspace theory, the information integration theory, and the dynamical core hypothesis. We discuss the venues of research opened by these results, emphasizing the need to extend the analytic methodology in order to obtain a dynamical picture of how functional interactions change over time and how their evolution is modulated during different conscious states. Finally, we discuss the need to experimentally establish absent or reduced conscious content, even when studying the deepest sleep stages.

  12. Sleep Neuroimaging and Models of Consciousness

    PubMed Central

    Tagliazucchi, Enzo; Behrens, Marion; Laufs, Helmut

    2013-01-01

    Human deep sleep is characterized by reduced sensory activity, responsiveness to stimuli, and conscious awareness. Given its ubiquity and reversible nature, it represents an attractive paradigm to study the neural changes which accompany the loss of consciousness in humans. In particular, the deepest stages of sleep can serve as an empirical test for the predictions of theoretical models relating the phenomenology of consciousness with underlying neural activity. A relatively recent shift of attention from the analysis of evoked responses toward spontaneous (or “resting state”) activity has taken place in the neuroimaging community, together with the development of tools suitable to study distributed functional interactions. In this review we focus on recent functional Magnetic Resonance Imaging (fMRI) studies of spontaneous activity during sleep and their relationship with theoretical models for human consciousness generation, considering the global workspace theory, the information integration theory, and the dynamical core hypothesis. We discuss the venues of research opened by these results, emphasizing the need to extend the analytic methodology in order to obtain a dynamical picture of how functional interactions change over time and how their evolution is modulated during different conscious states. Finally, we discuss the need to experimentally establish absent or reduced conscious content, even when studying the deepest sleep stages. PMID:23717291

  13. Neuroimaging after mild traumatic brain injury: Review and meta-analysis☆

    PubMed Central

    Eierud, Cyrus; Craddock, R. Cameron; Fletcher, Sean; Aulakh, Manek; King-Casas, Brooks; Kuehl, Damon; LaConte, Stephen M.

    2014-01-01

    This paper broadly reviews the study of mild traumatic brain injury (mTBI), across the spectrum of neuroimaging modalities. Among the range of imaging methods, however, magnetic resonance imaging (MRI) is unique in its applicability to studying both structure and function. Thus we additionally performed meta-analyses of MRI results to examine 1) the issue of anatomical variability and consistency for functional MRI (fMRI) findings, 2) the analogous issue of anatomical consistency for white-matter findings, and 3) the importance of accounting for the time post injury in diffusion weighted imaging reports. As we discuss, the human neuroimaging literature consists of both small and large studies spanning acute to chronic time points that have examined both structural and functional changes with mTBI, using virtually every available medical imaging modality. Two key commonalities have been used across the majority of imaging studies. The first is the comparison between mTBI and control populations. The second is the attempt to link imaging results with neuropsychological assessments. Our fMRI meta-analysis demonstrates a frontal vulnerability to mTBI, demonstrated by decreased signal in prefrontal cortex compared to controls. This vulnerability is further highlighted by examining the frequency of reported mTBI white matter anisotropy, in which we show a strong anterior-to-posterior gradient (with anterior regions being more frequently reported in mTBI). Our final DTI meta-analysis examines a debated topic arising from inconsistent anisotropy findings across studies. Our results support the hypothesis that acute mTBI is associated with elevated anisotropy values and chronic mTBI complaints are correlated with depressed anisotropy. Thus, this review and set of meta-analyses demonstrate several important points about the ongoing use of neuroimaging to understand the functional and structural changes that occur throughout the time course of mTBI recovery. Based on the

  14. Neuroimaging after mild traumatic brain injury: review and meta-analysis.

    PubMed

    Eierud, Cyrus; Craddock, R Cameron; Fletcher, Sean; Aulakh, Manek; King-Casas, Brooks; Kuehl, Damon; LaConte, Stephen M

    2014-01-01

    This paper broadly reviews the study of mild traumatic brain injury (mTBI), across the spectrum of neuroimaging modalities. Among the range of imaging methods, however, magnetic resonance imaging (MRI) is unique in its applicability to studying both structure and function. Thus we additionally performed meta-analyses of MRI results to examine 1) the issue of anatomical variability and consistency for functional MRI (fMRI) findings, 2) the analogous issue of anatomical consistency for white-matter findings, and 3) the importance of accounting for the time post injury in diffusion weighted imaging reports. As we discuss, the human neuroimaging literature consists of both small and large studies spanning acute to chronic time points that have examined both structural and functional changes with mTBI, using virtually every available medical imaging modality. Two key commonalities have been used across the majority of imaging studies. The first is the comparison between mTBI and control populations. The second is the attempt to link imaging results with neuropsychological assessments. Our fMRI meta-analysis demonstrates a frontal vulnerability to mTBI, demonstrated by decreased signal in prefrontal cortex compared to controls. This vulnerability is further highlighted by examining the frequency of reported mTBI white matter anisotropy, in which we show a strong anterior-to-posterior gradient (with anterior regions being more frequently reported in mTBI). Our final DTI meta-analysis examines a debated topic arising from inconsistent anisotropy findings across studies. Our results support the hypothesis that acute mTBI is associated with elevated anisotropy values and chronic mTBI complaints are correlated with depressed anisotropy. Thus, this review and set of meta-analyses demonstrate several important points about the ongoing use of neuroimaging to understand the functional and structural changes that occur throughout the time course of mTBI recovery. Based on the

  15. [Recent progress of neuroimaging studies on sleeping brain].

    PubMed

    Sasaki, Yuka

    2012-06-01

    Although sleep is a familiar phenomenon, its functions are yet to be elucidated. Understanding these functions of sleep is an important focus area in neuroscience. Electroencephalography (EEG) has been the predominantly used method in human sleep research but does not provide detailed spatial information about brain activation during sleep. To supplement the spatial information provided by this method, researchers have started using a combination of EEG and various advanced neuroimaging techniques that have been recently developed, including positron emission tomography (PET) and magnetic resonance imaging (MRI). In this paper, we will review the recent progress in sleep studies, especially studies that have used such advanced neuroimaging techniques. First, we will briefly introduce several neuroimaging techniques available for use in sleep studies. Next, we will review the spatiotemporal brain activation patterns during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, the dynamics of functional connectivity during sleep, and the consolidation of learning and memory during sleep; studies on the neural correlates of dreams, which have not yet been identified, will also be discussed. Lastly, possible directions for future research in this area will be discussed.

  16. Derivation of satellite wind model functions using operational surface wind analyses - An altimeter example

    NASA Technical Reports Server (NTRS)

    Freilich, Michael H.; Dunbar, R. S.

    1993-01-01

    One year of global surface wind products from multiple operational numerical weather prediction (NWP) forecast/analysis systems are used as comparison data to derive an empirical wind speed model function for the Geosat altimeter. The resulting model function is nearly identical to the modified Chelton-Wentz model for wind speeds from 4.5 to 15 m/s. Highly skewed distributions at low wind speeds are consistent with specular reflections and antenna mispointing errors hypothesized by others on the basis of extremely limited data. Mesoscale variability in the wind field and synoptic scale errors in the NWP products are shown to account for about 30 percent of the observed scatter of sigma(0) at each wind speed. The remaining scatter is largest at low winds, and decreases to a nearly constant value of about 12 percent at speeds greater than 7 m/s. Model function uncertainty expressed more traditionally in units of wind speed is examined for historical model functions as well as the present NWP-based model. The historical models have significant biases at high wind speeds owing to the lack of comparison in situ data used in their construction. The present study demonstrates that modern operational NWP surface wind products are sufficiently accurate to allow development of fully empirical model functions and associated error analyses.

  17. Molecular Neuroimaging in Posttraumatic Stress Disorder

    PubMed Central

    Im, Jooyeon Jamie; Namgung, Eun; Choi, Yejee; Kim, Jung Yoon; Rhie, Sandy Jeong

    2016-01-01

    Over the past decade, an increasing number of neuroimaging studies have provided insight into the neurobiological mechanisms of posttraumatic stress disorder (PSTD). In particular, molecular neuroimaging techniques have been employed in examining metabolic and neurochemical processes in PTSD. This article reviews molecular neuroimaging studies in PTSD and focuses on findings using three imaging modalities including positron emission tomography (PET), single photon emission computed tomography (SPECT), and magnetic resonance spectroscopy (MRS). Although there were some inconsistences in the findings, patients with PTSD showed altered cerebral metabolism and perfusion, receptor bindings, and metabolite profiles in the limbic regions, medial prefrontal cortex, and temporal cortex. Studies that have investigated brain correlates of treatment response are also reviewed. Lastly, the limitations of the molecular neuroimaging studies and potential future research directions are discussed. PMID:28035179

  18. Neuroimaging Biomarkers of Neurodegenerative Diseases and Dementia

    PubMed Central

    Risacher, Shannon L.; Saykin, Andrew J.

    2014-01-01

    Neurodegenerative disorders leading to dementia are common diseases that affect many older and some young adults. Neuroimaging methods are important tools for assessing and monitoring pathological brain changes associated with progressive neurodegenerative conditions. In this review, the authors describe key findings from neuroimaging studies (magnetic resonance imaging and radionucleotide imaging) in neurodegenerative disorders, including Alzheimer’s disease (AD) and prodromal stages, familial and atypical AD syndromes, frontotemporal dementia, amyotrophic lateral sclerosis with and without dementia, Parkinson’s disease with and without dementia, dementia with Lewy bodies, Huntington’s disease, multiple sclerosis, HIV-associated neurocognitive disorder, and prion protein associated diseases (i.e., Creutzfeldt-Jakob disease). The authors focus on neuroimaging findings of in vivo pathology in these disorders, as well as the potential for neuroimaging to provide useful information for differential diagnosis of neurodegenerative disorders. PMID:24234359

  19. Molecular neuroimaging in degenerative dementias.

    PubMed

    Jiménez Bonilla, J F; Carril Carril, J M

    2013-01-01

    In the context of the limitations of structural imaging, brain perfusion and metabolism using SPECT and PET have provided relevant information for the study of cognitive decline. The introduction of the radiotracers for cerebral amyloid imaging has changed the diagnostic strategy regarding Alzheimer's disease, which is currently considered to be a "continuum." According to this new paradigm, the increasing amyloid load would be associated to the preclinical phase and mild cognitive impairment. It has been possible to observe "in vivo" images using 11C-PIB and PET scans. The characteristics of the 11C-PIB image include specific high brain cortical area retention in the positive cases with typical distribution pattern and no retention in the negative cases. This, in combination with 18F-FDG PET, is the basis of molecular neuroimaging as a biomarker. At present, its prognostic value is being evaluated in longitudinal studies. 11C-PIB-PET has become the reference radiotracer to evaluate the presence of cerebral amyloid. However, its availability is limited due to the need for a nearby cyclotron. Therefore, 18F labeled radiotracers are being introduced. Our experience in the last two years with 11C-PIB, first in the research phase and then as being clinically applied, has shown the utility of the technique in the clinical field, either alone or in combination with FDG. Thus, amyloid image is a useful tool for the differential diagnosis of dementia and it is a potentially useful method for early diagnosis and evaluation of future treatments.

  20. Neuroimaging revolutionizes therapeutic approaches to chronic pain

    PubMed Central

    Borsook, David; Moulton, Eric A; Schmidt, Karl F; Becerra, Lino R

    2007-01-01

    An understanding of how the brain changes in chronic pain or responds to pharmacological or other therapeutic interventions has been significantly changed as a result of developments in neuroimaging of the CNS. These developments have occurred in 3 domains : (1) Anatomical Imaging which has demonstrated changes in brain volume in chronic pain; (2) Functional Imaging (fMRI) that has demonstrated an altered state in the brain in chronic pain conditions including back pain, neuropathic pain, and complex regional pain syndromes. In addition the response of the brain to drugs has provided new insights into how these may modify normal and abnormal circuits (phMRI or pharmacological MRI); (3) Chemical Imaging (Magnetic Resonance Spectroscopy or MRS) has helped our understanding of measures of chemical changes in chronic pain. Taken together these three domains have already changed the way in which we think of pain – it should now be considered an altered brain state in which there may be altered functional connections or systems and a state that has components of degenerative aspects of the CNS. PMID:17848191

  1. Neuroimaging in Tourette Syndrome: Research Highlights From 2014–2015

    PubMed Central

    Greene, Deanna J.; Schlaggar, Bradley L.; Black, Kevin J.

    2015-01-01

    Tourette Syndrome (ts) is a developmental neuropsychiatric disorder of the central nervous system defined by the presence of chronic tics. While investigations of the underlying brain mechanisms have provided valuable information, a complete understanding of the pathophysiology of ts remains elusive. Neuroimaging methods provide remarkable tools for examining the human brain, and have been used to study brain structure and function in ts. In this article, we review ts neuroimaging studies published in 2014–2015. We highlight a number of noteworthy studies due to their innovative methods and interesting findings. Yet, we note that many of the recent studies share common concerns, specifically susceptibility to motion artifacts and modest sample sizes. Thus, we encourage future work to carefully address potential methodological confounds and to study larger samples to increase the potential for replicable results. PMID:26543796

  2. Cognitive and emotional processes during dreaming: a neuroimaging view.

    PubMed

    Desseilles, Martin; Dang-Vu, Thien Thanh; Sterpenich, Virginie; Schwartz, Sophie

    2011-12-01

    Dream is a state of consciousness characterized by internally-generated sensory, cognitive and emotional experiences occurring during sleep. Dream reports tend to be particularly abundant, with complex, emotional, and perceptually vivid experiences after awakenings from rapid eye movement (REM) sleep. This is why our current knowledge of the cerebral correlates of dreaming, mainly derives from studies of REM sleep. Neuroimaging results show that REM sleep is characterized by a specific pattern of regional brain activity. We demonstrate that this heterogeneous distribution of brain activity during sleep explains many typical features in dreams. Reciprocally, specific dream characteristics suggest the activation of selective brain regions during sleep. Such an integration of neuroimaging data of human sleep, mental imagery, and the content of dreams is critical for current models of dreaming; it also provides neurobiological support for an implication of sleep and dreaming in some important functions such as emotional regulation.

  3. Heads in the Cloud: A Primer on Neuroimaging Applications of High Performance Computing

    PubMed Central

    Shatil, Anwar S.; Younas, Sohail; Pourreza, Hossein; Figley, Chase R.

    2015-01-01

    With larger data sets and more sophisticated analyses, it is becoming increasingly common for neuroimaging researchers to push (or exceed) the limitations of standalone computer workstations. Nonetheless, although high-performance computing platforms such as clusters, grids and clouds are already in routine use by a small handful of neuroimaging researchers to increase their storage and/or computational power, the adoption of such resources by the broader neuroimaging community remains relatively uncommon. Therefore, the goal of the current manuscript is to: 1) inform prospective users about the similarities and differences between computing clusters, grids and clouds; 2) highlight their main advantages; 3) discuss when it may (and may not) be advisable to use them; 4) review some of their potential problems and barriers to access; and finally 5) give a few practical suggestions for how interested new users can start analyzing their neuroimaging data using cloud resources. Although the aim of cloud computing is to hide most of the complexity of the infrastructure management from end-users, we recognize that this can still be an intimidating area for cognitive neuroscientists, psychologists, neurologists, radiologists, and other neuroimaging researchers lacking a strong computational background. Therefore, with this in mind, we have aimed to provide a basic introduction to cloud computing in general (including some of the basic terminology, computer architectures, infrastructure and service models, etc.), a practical overview of the benefits and drawbacks, and a specific focus on how cloud resources can be used for various neuroimaging applications. PMID:27279746

  4. Heads in the Cloud: A Primer on Neuroimaging Applications of High Performance Computing.

    PubMed

    Shatil, Anwar S; Younas, Sohail; Pourreza, Hossein; Figley, Chase R

    2015-01-01

    With larger data sets and more sophisticated analyses, it is becoming increasingly common for neuroimaging researchers to push (or exceed) the limitations of standalone computer workstations. Nonetheless, although high-performance computing platforms such as clusters, grids and clouds are already in routine use by a small handful of neuroimaging researchers to increase their storage and/or computational power, the adoption of such resources by the broader neuroimaging community remains relatively uncommon. Therefore, the goal of the current manuscript is to: 1) inform prospective users about the similarities and differences between computing clusters, grids and clouds; 2) highlight their main advantages; 3) discuss when it may (and may not) be advisable to use them; 4) review some of their potential problems and barriers to access; and finally 5) give a few practical suggestions for how interested new users can start analyzing their neuroimaging data using cloud resources. Although the aim of cloud computing is to hide most of the complexity of the infrastructure management from end-users, we recognize that this can still be an intimidating area for cognitive neuroscientists, psychologists, neurologists, radiologists, and other neuroimaging researchers lacking a strong computational background. Therefore, with this in mind, we have aimed to provide a basic introduction to cloud computing in general (including some of the basic terminology, computer architectures, infrastructure and service models, etc.), a practical overview of the benefits and drawbacks, and a specific focus on how cloud resources can be used for various neuroimaging applications.

  5. Research updates in neuroimaging studies of children who stutter.

    PubMed

    Chang, Soo-Eun

    2014-05-01

    In the past two decades, neuroimaging investigations of stuttering have led to important discoveries of structural and functional brain differences in people who stutter, providing significant clues to the neurological basis of stuttering. One major limitation, however, has been that most studies so far have only examined adults who stutter, whose brain and behavior likely would have adopted compensatory reactions to their stuttering; these confounding factors have made interpretations of the findings difficult. Developmental stuttering is a neurodevelopmental condition, and like many other neurodevelopmental disorders, stuttering is associated with an early childhood onset of symptoms and greater incidence in males relative to females. More recent studies have begun to examine children who stutter using various neuroimaging techniques that allow examination of functional neuroanatomy and interaction of major brain areas that differentiate children who stutter compared with age-matched controls. In this article, I review these more recent neuroimaging investigations of children who stutter, in the context of what we know about typical brain development, neuroplasticity, and sex differences relevant to speech and language development. Although the picture is still far from complete, these studies have potential to provide information that can be used as early objective markers, or prognostic indicators, for persistent stuttering in the future. Furthermore, these studies are the first steps in finding potential neural targets for novel therapies that may involve modulating neuroplastic growth conducive to developing and maintaining fluent speech, which can be applied to treatment of young children who stutter.

  6. Human neuroimaging as a "Big Data" science.

    PubMed

    Van Horn, John Darrell; Toga, Arthur W

    2014-06-01

    The maturation of in vivo neuroimaging has led to incredible quantities of digital information about the human brain. While much is made of the data deluge in science, neuroimaging represents the leading edge of this onslaught of "big data". A range of neuroimaging databasing approaches has streamlined the transmission, storage, and dissemination of data from such brain imaging studies. Yet few, if any, common solutions exist to support the science of neuroimaging. In this article, we discuss how modern neuroimaging research represents a multifactorial and broad ranging data challenge, involving the growing size of the data being acquired; sociological and logistical sharing issues; infrastructural challenges for multi-site, multi-datatype archiving; and the means by which to explore and mine these data. As neuroimaging advances further, e.g. aging, genetics, and age-related disease, new vision is needed to manage and process this information while marshalling of these resources into novel results. Thus, "big data" can become "big" brain science.

  7. Neuroimaging essentials in essential tremor: A systematic review

    PubMed Central

    Sharifi, Sarvi; Nederveen, Aart J.; Booij, Jan; van Rootselaar, Anne-Fleur

    2014-01-01

    Background Essential tremor is regarded to be a disease of the central nervous system. Neuroimaging is a rapidly growing field with potential benefits to both diagnostics and research. The exact role of imaging techniques with respect to essential tremor in research and clinical practice is not clear. A systematic review of the different imaging techniques in essential tremor is lacking in the literature. Methods We performed a systematic literature search combining the terms essential tremor and familial tremor with the following keywords: imaging, MRI, VBM, DWI, fMRI, PET and SPECT, both in abbreviated form as well as in full form. We summarize and discuss the quality and the external validity of each study and place the results in the context of existing knowledge regarding the pathophysiology of essential tremor. Results A total of 48 neuroimaging studies met our search criteria, roughly divided into 19 structural and 29 functional and metabolic studies. The quality of the studies varied, especially concerning inclusion criteria. Functional imaging studies indicated cerebellar hyperactivity during rest and during tremor. The studies also pointed to the involvement of the thalamus, the inferior olive and the red nucleus. Structural studies showed less consistent results. Discussion and conclusion Neuroimaging techniques in essential tremor give insight into the pathophysiology of essential tremor indicating the involvement of the cerebellum as the most consistent finding. GABAergic dysfunction might be a major premise in the pathophysiological hypotheses. Inconsistencies between studies can be partly explained by the inclusion of heterogeneous patient groups. Improvement of scientific research requires more stringent inclusion criteria and application of advanced analysis techniques. Also, the use of multimodal neuroimaging techniques is a promising development in movement disorders research. Currently, the role of imaging techniques in essential tremor in daily

  8. Brain signature of chronic orofacial pain: a systematic review and meta-analysis on neuroimaging research of trigeminal neuropathic pain and temporomandibular joint disorders.

    PubMed

    Lin, Chia-Shu

    2014-01-01

    Brain neuroimaging has been widely used to investigate the bran signature of chronic orofacial pain, including trigeminal neuropathic pain (TNP) and pain related to temporomandibular joint disorders (TMD). We here systematically reviewed the neuroimaging literature regarding the functional and structural changes in the brain of TNP and TMD pain patients, using a computerized search of journal articles via PubMed. Ten TNP studies and 14 TMD studies were reviewed. Study quality and risk of bias were assessed based on the criteria of patient selection, the history of medication, the use of standardized pain/psychological assessments, and the model and statistics of imaging analyses. Qualitative meta-analysis was performed by examining the brain regions which showed significant changes in either brain functions (including the blood-oxygen-level dependent signal, cerebral blood flow and the magnetic resonance spectroscopy signal) or brain structure (including gray matter and white matter anatomy). We hypothesized that the neuroimaging findings would display a common pattern as well as distinct patterns of brain signature in the disorders. This major hypothesis was supported by the following findings: (1) TNP and TMD patients showed consistent functional/structural changes in the thalamus and the primary somatosensory cortex, indicating the thalamocortical pathway as the major site of plasticity. (2) The TNP patients showed more alterations at the thalamocortical pathway, and the two disorders showed distinct patterns of thalamic and insular connectivity. Additionally, functional and structural changes were frequently reported in the prefrontal cortex and the basal ganglia, suggesting the role of cognitive modulation and reward processing in chronic orofacial pain. The findings highlight the potential for brain neuroimaging as an investigating tool for understanding chronic orofacial pain.

  9. Elucidation of molecular and functional heterogeneity through differential expression network analyses of discrete tumor subsets

    PubMed Central

    Naik, Rutika R.; Gardi, Nilesh L.; Bapat, Sharmila A.

    2016-01-01

    Intratumor heterogeneity presents a major hurdle in cancer therapy. Most current research studies consider tumors as single entities and overlook molecular diversity between heterogeneous state(s) of different cells assumed to be homogenous. The present approach was designed for fluorescence-activated cell sorting-based resolution of heterogeneity arising from cancer stem cell (CSC) hierarchies and genetic instability in ovarian tumors, followed by microarray-based expression profiling of sorted fractions. Through weighted gene correlation network analyses, we could assign enriched modules of co-regulated genes to each fraction. Such gene modules often correlate with biological functions; one such specific association was the enrichment of CD53 expression in CSCs, functional validation indicated CD53 to be a tumor-initiating cell- rather than quiescent CSC-marker. Another association defined a state of poise for stress-induced metastases in aneuploid cells. Our results thus emphasize the need for studying cell-specific functionalities relevant to regeneration, drug resistance and disease progression in discrete tumor cell fractions. PMID:27140846

  10. Phenetic and functional analyses of the distal ulna of Australopithecus afarensis and Australopithecus africanus.

    PubMed

    Tallman, Melissa

    2015-01-01

    The morphology of the distal portion of the hominoid ulna is poorly studied despite its important functional role at the wrist joint. There are five qualitatively well-described fossil hominin distal ulnae belonging to Australopithecus afarensis and Australopithecus africanus, but there have been few efforts to quantify their morphology or relate it to their functional abilities. This article presents an effort to do so, using three-dimensional geometric morphometrics to analyze the shape of the distal ulna of the Plio-Pleistocene hominins and an extant comparative sample of great apes and humans. For the extant taxa, results show that the morphology of Pan and Pongo is distinct from that of Homo, and that these differences are likely related to climbing, clambering and below-branch suspension in the former, and the release of the limbs from locomotion and (potentially) tool manufacture in the latter. For the australopiths, results indicate that the A. afarensis sample is relatively heterogeneous. These results are driven by the morphology of A.L. 333-12, which is the largest ulna in the sample and has a unique combination of traits when compared with the other two A. afarensis specimens. Overall, the morphology of all the hominins was most consistent with the pattern displayed by extant great apes, and specifically Pan and Pongo; however, large overlap in shape in the distal ulna in the extant sample indicates that other areas of the skeleton may be more informative for functional analyses.

  11. Computer-aided analyses of transport protein sequences: gleaning evidence concerning function, structure, biogenesis, and evolution.

    PubMed Central

    Saier, M H

    1994-01-01

    Three-dimensional structures have been elucidated for very few integral membrane proteins. Computer methods can be used as guides for estimation of solute transport protein structure, function, biogenesis, and evolution. In this paper the application of currently available computer programs to over a dozen distinct families of transport proteins is reviewed. The reliability of sequence-based topological and localization analyses and the importance of sequence and residue conservation to structure and function are evaluated. Evidence concerning the nature and frequency of occurrence of domain shuffling, splicing, fusion, deletion, and duplication during evolution of specific transport protein families is also evaluated. Channel proteins are proposed to be functionally related to carriers. It is argued that energy coupling to transport was a late occurrence, superimposed on preexisting mechanisms of solute facilitation. It is shown that several transport protein families have evolved independently of each other, employing different routes, at different times in evolutionary history, to give topologically similar transmembrane protein complexes. The possible significance of this apparent topological convergence is discussed. PMID:8177172

  12. Evolutionary Analyses Suggest a Function of MxB Immunity Proteins Beyond Lentivirus Restriction

    PubMed Central

    Mitchell, Patrick S.; Young, Janet M.; Emerman, Michael; Malik, Harmit S.

    2015-01-01

    Viruses impose diverse and dynamic challenges on host defenses. Diversifying selection of codons and gene copy number variation are two hallmarks of genetic innovation in antiviral genes engaged in host-virus genetic conflicts. The myxovirus resistance (Mx) genes encode interferon-inducible GTPases that constitute a major arm of the cell-autonomous defense against viral infection. Unlike the broad antiviral activity of MxA, primate MxB was recently shown to specifically inhibit lentiviruses including HIV-1. We carried out detailed evolutionary analyses to investigate whether genetic conflict with lentiviruses has shaped MxB evolution in primates. We found strong evidence for diversifying selection in the MxB N-terminal tail, which contains molecular determinants of MxB anti-lentivirus specificity. However, we found no overlap between previously-mapped residues that dictate lentiviral restriction and those that have evolved under diversifying selection. Instead, our findings are consistent with MxB having a long-standing and important role in the interferon response to viral infection against a broader range of pathogens than is currently appreciated. Despite its critical role in host innate immunity, we also uncovered multiple functional losses of MxB during mammalian evolution, either by pseudogenization or by gene conversion from MxA genes. Thus, although the majority of mammalian genomes encode two Mx genes, this apparent stasis masks the dramatic effects that recombination and diversifying selection have played in shaping the evolutionary history of Mx genes. Discrepancies between our study and previous publications highlight the need to account for recombination in analyses of positive selection, as well as the importance of using sequence datasets with appropriate depth of divergence. Our study also illustrates that evolutionary analyses of antiviral gene families are critical towards understanding molecular principles that govern host-virus interactions and

  13. Transcriptome analyses reveal molecular mechanisms underlying functional recovery after spinal cord injury

    PubMed Central

    Duan, Hongmei; Ge, Weihong; Zhang, Aifeng; Xi, Yue; Chen, Zhihua; Luo, Dandan; Cheng, Yin; Fan, Kevin S.; Horvath, Steve; Sofroniew, Michael V.; Cheng, Liming; Yang, Zhaoyang; Sun, Yi E.; Li, Xiaoguang

    2015-01-01

    Spinal cord injury (SCI) is considered incurable because axonal regeneration in the central nervous system (CNS) is extremely challenging, due to harsh CNS injury environment and weak intrinsic regeneration capability of CNS neurons. We discovered that neurotrophin-3 (NT3)-loaded chitosan provided an excellent microenvironment to facilitate nerve growth, new neurogenesis, and functional recovery of completely transected spinal cord in rats. To acquire mechanistic insight, we conducted a series of comprehensive transcriptome analyses of spinal cord segments at the lesion site, as well as regions immediately rostral and caudal to the lesion, over a period of 90 days after SCI. Using weighted gene coexpression network analysis (WGCNA), we established gene modules/programs corresponding to various pathological events at different times after SCI. These objective measures of gene module expression also revealed that enhanced new neurogenesis and angiogenesis, and reduced inflammatory responses were keys to conferring the effect of NT3-chitosan on regeneration. PMID:26460053

  14. Advances in Omics and Bioinformatics Tools for Systems Analyses of Plant Functions

    PubMed Central

    Mochida, Keiichi; Shinozaki, Kazuo

    2011-01-01

    Omics and bioinformatics are essential to understanding the molecular systems that underlie various plant functions. Recent game-changing sequencing technologies have revitalized sequencing approaches in genomics and have produced opportunities for various emerging analytical applications. Driven by technological advances, several new omics layers such as the interactome, epigenome and hormonome have emerged. Furthermore, in several plant species, the development of omics resources has progressed to address particular biological properties of individual species. Integration of knowledge from omics-based research is an emerging issue as researchers seek to identify significance, gain biological insights and promote translational research. From these perspectives, we provide this review of the emerging aspects of plant systems research based on omics and bioinformatics analyses together with their associated resources and technological advances. PMID:22156726

  15. Integrative functional genomic analyses implicate specific molecular pathways and circuits in autism.

    PubMed

    Parikshak, Neelroop N; Luo, Rui; Zhang, Alice; Won, Hyejung; Lowe, Jennifer K; Chandran, Vijayendran; Horvath, Steve; Geschwind, Daniel H

    2013-11-21

    Genetic studies have identified dozens of autism spectrum disorder (ASD) susceptibility genes, raising two critical questions: (1) do these genetic loci converge on specific biological processes, and (2) where does the phenotypic specificity of ASD arise, given its genetic overlap with intellectual disability (ID)? To address this, we mapped ASD and ID risk genes onto coexpression networks representing developmental trajectories and transcriptional profiles representing fetal and adult cortical laminae. ASD genes tightly coalesce in modules that implicate distinct biological functions during human cortical development, including early transcriptional regulation and synaptic development. Bioinformatic analyses suggest that translational regulation by FMRP and transcriptional coregulation by common transcription factors connect these processes. At a circuit level, ASD genes are enriched in superficial cortical layers and glutamatergic projection neurons. Furthermore, we show that the patterns of ASD and ID risk genes are distinct, providing a biological framework for further investigating the pathophysiology of ASD.

  16. Transcriptome analyses reveal molecular mechanisms underlying functional recovery after spinal cord injury.

    PubMed

    Duan, Hongmei; Ge, Weihong; Zhang, Aifeng; Xi, Yue; Chen, Zhihua; Luo, Dandan; Cheng, Yin; Fan, Kevin S; Horvath, Steve; Sofroniew, Michael V; Cheng, Liming; Yang, Zhaoyang; Sun, Yi E; Li, Xiaoguang

    2015-10-27

    Spinal cord injury (SCI) is considered incurable because axonal regeneration in the central nervous system (CNS) is extremely challenging, due to harsh CNS injury environment and weak intrinsic regeneration capability of CNS neurons. We discovered that neurotrophin-3 (NT3)-loaded chitosan provided an excellent microenvironment to facilitate nerve growth, new neurogenesis, and functional recovery of completely transected spinal cord in rats. To acquire mechanistic insight, we conducted a series of comprehensive transcriptome analyses of spinal cord segments at the lesion site, as well as regions immediately rostral and caudal to the lesion, over a period of 90 days after SCI. Using weighted gene coexpression network analysis (WGCNA), we established gene modules/programs corresponding to various pathological events at different times after SCI. These objective measures of gene module expression also revealed that enhanced new neurogenesis and angiogenesis, and reduced inflammatory responses were keys to conferring the effect of NT3-chitosan on regeneration.

  17. Neuroimaging studies in people with gender incongruence.

    PubMed

    Kreukels, Baudewijntje P C; Guillamon, Antonio

    2016-01-01

    The current review gives an overview of brain studies in transgender people. First, we describe studies into the aetiology of feelings of gender incongruence, primarily addressing the sexual differentiation hypothesis: does the brain of transgender individuals resemble that of their natal sex, or that of their experienced gender? Findings from neuroimaging studies focusing on brain structure suggest that the brain phenotypes of trans women (MtF) and trans men (FtM) differ in various ways from control men and women with feminine, masculine, demasculinized and defeminized features. The brain phenotypes of people with feelings of gender incongruence may help us to figure out whether sex differentiation of the brain is atypical in these individuals, and shed light on gender identity development. Task-related imaging studies may show whether brain activation and task performance in transgender people is sex-atypical. Second, we review studies that evaluate the effects of cross-sex hormone treatment on the brain. This type of research provides knowledge on how changes in sex hormone levels may affect brain structure and function.

  18. Functional and structural analyses of mouse genomic regions screened by the morphological specific-locus test.

    PubMed

    Russell, L B

    1989-05-01

    Genetic analyses of certain classes of mutations recovered in the mouse specific-locus test (SLT) have characterized arrays of deletions, overlapping at the marked loci. Complementation maps, generated for several of the regions, have identified a number of functional units surrounding each marked locus and have ordered the mutations into complementation groups. Molecular entry to all but one of the marked regions has been achieved by (1) identifying proviral integrations in, or close to, the specific loci (d, se, a, c); (2) mapping random anonymous clones from appropriately enriched libraries to the longest deleted segments, then submapping to more limited segments on the basis of complementation and deletion-breakpoint maps (c, p); (3) similarly mapping known clones thought to be located in pertinent chromosomal regions (p, c, d); and (4) cloning specific genes that reside in regions corresponding to the deletions (b, c, p). The molecular analyses have confirmed that genetically-inferred deletions are structural deletions of DNA. The emerging physical maps are concordant with the complementation maps, and in several cases have discriminated among members of a complementation group with respect to breakpoint positions. Deletion-breakpoint-fusion fragments have prove to be highly useful for making large chromosomal jumps to facilitate physical mapping. The recent advances toward correlating physical and functional maps of specific regions of the mouse genome owe much to the existence of arrays of mutations involving loci marked in the SLT. In turn, the characterizations of these regions have made it possible to demonstrate qualitative differences among mutations resulting from different treatments. This new capability for qualitative analysis, which will increase as the molecular studies proceed, further enhances the value of the SLT, which has been extensively used for quantitative studies in germ-cell mutagenesis.

  19. Genome-wide identification and functional analyses of calmodulin genes in Solanaceous species

    PubMed Central

    2013-01-01

    Background Calmodulin (CaM) is a major calcium sensor in all eukaryotes. It binds calcium and modulates the activity of a wide range of downstream proteins in response to calcium signals. However, little is known about the CaM gene family in Solanaceous species, including the economically important species, tomato (Solanum lycopersicum), and the gene silencing model plant, Nicotiana benthamiana. Moreover, the potential function of CaM in plant disease resistance remains largely unclear. Results We performed genome-wide identification of CaM gene families in Solanaceous species. Employing bioinformatics approaches, multiple full-length CaM genes were identified from tomato, N. benthamiana and potato (S. tuberosum) genomes, with tomato having 6 CaM genes, N. benthamiana having 7 CaM genes, and potato having 4 CaM genes. Sequence comparison analyses showed that three tomato genes, SlCaM3/4/5, two potato genes StCaM2/3, and two sets of N. benthamiana genes, NbCaM1/2/3/4 and NbCaM5/6, encode identical CaM proteins, yet the genes contain different intron/exon organization and are located on different chromosomes. Further sequence comparisons and gene structural and phylogenetic analyses reveal that Solanaceous species gained a new group of CaM genes during evolution. These new CaM genes are unusual in that they contain three introns in contrast to only a single intron typical of known CaM genes in plants. The tomato CaM (SlCaM) genes were found to be expressed in all organs. Prediction of cis-acting elements in 5' upstream sequences and expression analyses demonstrated that SlCaM genes have potential to be highly responsive to a variety of biotic and abiotic stimuli. Additionally, silencing of SlCaM2 and SlCaM6 altered expression of a set of signaling and defense-related genes and resulted in significantly lower resistance to Tobacco rattle virus and the oomycete pathogen, Pythium aphanidermatum. Conclusions The CaM gene families in the Solanaceous species tomato, N

  20. Remember the Future II: Meta-analyses and Functional Overlap of Working Memory and Delay Discounting

    PubMed Central

    Wesley, Michael J.; Bickel, Warren K.

    2013-01-01

    Background Previously we showed that working memory training decreased the discounting of future rewards in stimulant addicts without affecting a Go/NoGo task. While a relationship between delay discounting and working memory is consistent with other studies, the unique brain regions of plausible causality between these two abilities have yet to be determined. Methods Activation likelihood estimation (ALE) meta-analyses were performed on foci from studies of delay discounting (DD = 449), working memory (WM = 452), finger tapping (FT = 450), and response inhibition (RI = 450). Activity maps from relatively less (FT) and more (RI) demanding executive tasks were contrasted with maps of DD and WM. Overlap analysis identified unique functional coincidence between DD and WM. Results The anterior cingulate cortex was engaged by all tasks. FT largely engaged motor-related brain areas. In addition to motor-related areas, RI engaged frontal brain regions. The right lateral prefrontal cortex was engaged by RI, DD and WM and was contrasted out of overlap maps. A functional cluster in the posterior portion of the left lateral prefrontal cortex emerged as the largest location of unique overlap between DD and WM. Conclusions A portion of the left lateral prefrontal cortex is a unique location where delay discounting and working memory processes overlap in the brain. This area, therefore, represents a therapeutic target for improving behaviors that rely on the integration of the recent past with the foreseeable future. PMID:24041504

  1. Evolution-guided functional analyses reveal diverse antiviral specificities encoded by IFIT1 genes in mammals

    PubMed Central

    Daugherty, Matthew D; Schaller, Aaron M; Geballe, Adam P; Malik, Harmit S

    2016-01-01

    IFIT (interferon-induced with tetratricopeptide repeats) proteins are critical mediators of mammalian innate antiviral immunity. Mouse IFIT1 selectively inhibits viruses that lack 2'O-methylation of their mRNA 5' caps. Surprisingly, human IFIT1 does not share this antiviral specificity. Here, we resolve this discrepancy by demonstrating that human and mouse IFIT1 have evolved distinct functions using a combination of evolutionary, genetic and virological analyses. First, we show that human IFIT1 and mouse IFIT1 (renamed IFIT1B) are not orthologs, but are paralogs that diverged >100 mya. Second, using a yeast genetic assay, we show that IFIT1 and IFIT1B proteins differ in their ability to be suppressed by a cap 2'O-methyltransferase. Finally, we demonstrate that IFIT1 and IFIT1B have divergent antiviral specificities, including the discovery that only IFIT1 proteins inhibit a virus encoding a cap 2'O-methyltransferase. These functional data, combined with widespread turnover of mammalian IFIT genes, reveal dramatic species-specific differences in IFIT-mediated antiviral repertoires. DOI: http://dx.doi.org/10.7554/eLife.14228.001 PMID:27240734

  2. Cognitive disorders in pediatric medulloblastoma: what neuroimaging has to offer.

    PubMed

    Hoang, Duc Ha; Pagnier, Anne; Guichardet, Karine; Dubois-Teklali, Fanny; Schiff, Isabelle; Lyard, Geneviève; Cousin, Emilie; Krainik, Alexandre

    2014-08-01

    Medulloblastomas are the most common malignant childhood brain tumors arising in the posterior fossa. Treatment improvements for these tumors have meant that there are a greater number of survivors, but this long-term patient survival has increased the awareness of resulting neurocognitive deficits. Impairments in attention, memory, executive functions, and intelligence quotient demonstrate that the cerebellum likely plays a significant role in numerous higher cognitive functions such as language, cognitive, and emotional functions. In addition, children with medulloblastoma not only have cerebellar lesions but also brain white matter damages due to radiation and chemotherapy. Functional neuroimaging, a noninvasive method with many advantages, has become the standard tool in clinical and cognitive neuroscience research. By reviewing functional neuroimaging studies, this review aims to clarify the role of the cerebellum in cognitive function and explain more clearly cognitive sequelae due to polytherapy in children with medulloblastoma. This review suggests that the posterior cerebellar lobes are crucial to maintaining cognitive performance. Clinical investigations could help to better assess the involvement of these lobes in cognitive functions.

  3. Preliminary results of receiver function analyses at three sites across the Bransfield Strait, Antarctica

    NASA Astrophysics Data System (ADS)

    Martínez Arévalo, C.; Mancilla, F.; Almendros, J.; Aznarte, J. L.; Alguacil, G.

    2009-04-01

    In February 2008, in the framework of the International Polar Year 2008-2009 under grant POL2006-08663 of the spanish Ministry of Education, we deployed three broadband seismometers at points forming a N-S profile across the Bransfield Strait, Antarctica, in the region between the South Shetland Islands and the Antarctic Peninsula. This region is very interesting from a tectonic point of view, due to the opening of the rift of the Bransfield and the presence of the South Shetland microplate. For logistic reasons, our instruments where located in the vicinity of the Antarctic bases Juan Carlos I (Livingston Island), Gabriel de Castilla (Deception Island), and Primavera (Antarctic Peninsula). Each seismic station consisted of a broad-band, three-component electrolitic seismometer equiped with a 24-bit data acquisition system. The energy was provided by wind generators and solar panels connected to a battery bank, a combination that has been able to provide enough power at all sites, even during the Antarctic winter. All components were designed to function under the extreme conditions of the Antarctic weather. The main objective of this experiment was to use receiver function techniques on teleseism data to investigate the structure of the crust under the sites, in order to compare with other studies and shed light on the structure and tectonics of the region. During this past year, we have recorded several tens of teleseisms at distances appropriate for receiver function analyses. Preliminary results will add information on critical issues regarding the structure of the Bransfield Strait region. Although the Earth models obtained will contain extra information, we are specially interested in the determination of the depth of the Moho at each site, a controversial point in this area. These results will be compared with estimates obtained by different techniques. We are also interested in the determination of the vertical extent of the magma chamber recently imaged by

  4. Derivation, Replication, and Validity Analyses of a Screener for the Behavioral Assessment of Executive Functions in Young Adults.

    PubMed

    Duggan, Emily C; Garcia-Barrera, Mauricio A; Müller, Ulrich

    2016-09-21

    Ecologically valid indicators of executive functions are designed to capture dysfunction not easily measured in a lab setting. Here, we present two studies on the development and validity analyses of a behavioral screener for executive functions among young adults. In Study 1, we derived a four-factor (problem solving, attentional control, behavioral control, and emotional control) behavioral screener using a sample of 765 individuals. We used invariance analyses to evaluate the screener's measurement reliability across sex. In Study 2, we replicated the screener derivation analyses using an independent sample of 197 undergraduates. To further examine the screener's validity, we evaluated it against a well-known executive functions rating scale. The four-factor model was supported in both samples and analyses provided support for this screener as a valid and reliable measure for everyday executive functions among young adults.

  5. Genome-Wide Identification and Function Analyses of Heat Shock Transcription Factors in Potato

    PubMed Central

    Tang, Ruimin; Zhu, Wenjiao; Song, Xiaoyan; Lin, Xingzhong; Cai, Jinghui; Wang, Man; Yang, Qing

    2016-01-01

    Heat shock transcription factors (Hsfs) play vital roles in the regulation of tolerance to various stresses in living organisms. To dissect the mechanisms of the Hsfs in potato adaptation to abiotic stresses, genome and transcriptome analyses of Hsf gene family were investigated in Solanum tuberosum L. Twenty-seven StHsf members were identified by bioinformatics and phylogenetic analyses and were classified into A, B, and C groups according to their structural and phylogenetic features. StHsfs in the same class shared similar gene structures and conserved motifs. The chromosomal location analysis showed that 27 Hsfs were located in 10 of 12 chromosomes (except chromosome 1 and chromosome 5) and that 18 of these genes formed 9 paralogous pairs. Expression profiles of StHsfs in 12 different organs and tissues uncovered distinct spatial expression patterns of these genes and their potential roles in the process of growth and development. Promoter and quantitative real-time polymerase chain reaction (qRT-PCR) detections of StHsfs were conducted and demonstrated that these genes were all responsive to various stresses. StHsf004, StHsf007, StHsf009, StHsf014, and StHsf019 were constitutively expressed under non-stress conditions, and some specific Hsfs became the predominant Hsfs in response to different abiotic stresses, indicating their important and diverse regulatory roles in adverse conditions. A co-expression network between StHsfs and StHsf -co-expressed genes was generated based on the publicly-available potato transcriptomic databases and identified key candidate StHsfs for further functional studies. PMID:27148315

  6. Neuroimaging characteristics of dementia with Lewy bodies.

    PubMed

    Mak, Elijah; Su, Li; Williams, Guy B; O'Brien, John T

    2014-01-01

    This review summarises the findings and applications from neuroimaging studies in dementia with Lewy bodies (DLB), highlighting key differences between DLB and other subtypes of dementia. We also discuss the increasingly important role of imaging biomarkers in differential diagnosis and outline promising areas for future research in DLB. DLB shares common clinical, neuropsychological and pathological features with Parkinson's disease dementia and other dementia subtypes, such as Alzheimer's disease. Despite the development of consensus diagnostic criteria, the sensitivity for differential diagnosis of DLB in clinical practice remains low and many DLB patients will be misdiagnosed. The importance of developing accurate imaging markers in dementia is highlighted by the potential for treatments targeting specific molecular abnormalities as well as the responsiveness to cholinesterase inhibitors and marked neuroleptic sensitivity of DLB. We review various brain imaging techniques that have been applied to investigate DLB, including the characteristic nigrostriatal degeneration in DLB using positron emission tomography (PET) and single-photon emission computed tomography (SPECT) tracers. Dopamine transporter loss has proven to reliably differentiate DLB from other dementias and has been incorporated into the revised clinical diagnostic criteria for DLB. To date, this remains the 'gold standard' for diagnostic imaging of DLB. Regional cerebral blood flow, 18 F-fluorodeoxygluclose-PET and SPECT have also identified marked deficits in the occipital regions with relative sparing of the medial temporal lobe when compared to Alzheimer's disease. In addition, structural, diffusion, and functional magnetic resonance imaging techniques have shown alterations in structure, white matter integrity, and functional activity in DLB. We argue that the multimodal identification of DLB-specific biomarkers has the potential to improve ante-mortem diagnosis and contribute to our

  7. Multimodal neuroimaging computing: the workflows, methods, and platforms.

    PubMed

    Liu, Sidong; Cai, Weidong; Liu, Siqi; Zhang, Fan; Fulham, Michael; Feng, Dagan; Pujol, Sonia; Kikinis, Ron

    The last two decades have witnessed the explosive growth in the development and use of noninvasive neuroimaging technologies that advance the research on human brain under normal and pathological conditions. Multimodal neuroimaging has become a major driver of current neuroimaging research due to the recognition of the clinical benefits of multimodal data, and the better access to hybrid devices. Multimodal neuroimaging computing is very challenging, and requires sophisticated computing to address the variations in spatiotemporal resolution and merge the biophysical/biochemical information. We review the current workflows and methods for multimodal neuroimaging computing, and also demonstrate how to conduct research using the established neuroimaging computing packages and platforms.

  8. Multimodal neuroimaging computing: the workflows, methods, and platforms.

    PubMed

    Liu, Sidong; Cai, Weidong; Liu, Siqi; Zhang, Fan; Fulham, Michael; Feng, Dagan; Pujol, Sonia; Kikinis, Ron

    2015-09-01

    The last two decades have witnessed the explosive growth in the development and use of noninvasive neuroimaging technologies that advance the research on human brain under normal and pathological conditions. Multimodal neuroimaging has become a major driver of current neuroimaging research due to the recognition of the clinical benefits of multimodal data, and the better access to hybrid devices. Multimodal neuroimaging computing is very challenging, and requires sophisticated computing to address the variations in spatiotemporal resolution and merge the biophysical/biochemical information. We review the current workflows and methods for multimodal neuroimaging computing, and also demonstrate how to conduct research using the established neuroimaging computing packages and platforms.

  9. Molecular neuroimaging of emotional decision-making.

    PubMed

    Takahashi, Hidehiko

    2013-04-01

    With the dissemination of non-invasive human neuroimaging techniques such as fMRI and the advancement of cognitive science, neuroimaging studies focusing on emotions and social cognition have become established. Along with this advancement, behavioral economics taking emotional and social factors into account for economic decisions has been merged with neuroscientific studies, and this interdisciplinary approach is called neuroeconomics. Past neuroeconomics studies have demonstrated that subcortical emotion-related brain structures play an important role in "irrational" decision-making. The research field that investigates the role of central neurotransmitters in this process is worthy of further development. Here, we provide an overview of recent molecular neuroimaging studies to further the understanding of the neurochemical basis of "irrational" or emotional decision-making and the future direction, including clinical implications, of the field.

  10. Using Dual Regression to Investigate Network Shape and Amplitude in Functional Connectivity Analyses

    PubMed Central

    Nickerson, Lisa D.; Smith, Stephen M.; Öngür, Döst; Beckmann, Christian F.

    2017-01-01

    Independent Component Analysis (ICA) is one of the most popular techniques for the analysis of resting state FMRI data because it has several advantageous properties when compared with other techniques. Most notably, in contrast to a conventional seed-based correlation analysis, it is model-free and multivariate, thus switching the focus from evaluating the functional connectivity of single brain regions identified a priori to evaluating brain connectivity in terms of all brain resting state networks (RSNs) that simultaneously engage in oscillatory activity. Furthermore, typical seed-based analysis characterizes RSNs in terms of spatially distributed patterns of correlation (typically by means of simple Pearson's coefficients) and thereby confounds together amplitude information of oscillatory activity and noise. ICA and other regression techniques, on the other hand, retain magnitude information and therefore can be sensitive to both changes in the spatially distributed nature of correlations (differences in the spatial pattern or “shape”) as well as the amplitude of the network activity. Furthermore, motion can mimic amplitude effects so it is crucial to use a technique that retains such information to ensure that connectivity differences are accurately localized. In this work, we investigate the dual regression approach that is frequently applied with group ICA to assess group differences in resting state functional connectivity of brain networks. We show how ignoring amplitude effects and how excessive motion corrupts connectivity maps and results in spurious connectivity differences. We also show how to implement the dual regression to retain amplitude information and how to use dual regression outputs to identify potential motion effects. Two key findings are that using a technique that retains magnitude information, e.g., dual regression, and using strict motion criteria are crucial for controlling both network amplitude and motion-related amplitude

  11. Using Dual Regression to Investigate Network Shape and Amplitude in Functional Connectivity Analyses.

    PubMed

    Nickerson, Lisa D; Smith, Stephen M; Öngür, Döst; Beckmann, Christian F

    2017-01-01

    Independent Component Analysis (ICA) is one of the most popular techniques for the analysis of resting state FMRI data because it has several advantageous properties when compared with other techniques. Most notably, in contrast to a conventional seed-based correlation analysis, it is model-free and multivariate, thus switching the focus from evaluating the functional connectivity of single brain regions identified a priori to evaluating brain connectivity in terms of all brain resting state networks (RSNs) that simultaneously engage in oscillatory activity. Furthermore, typical seed-based analysis characterizes RSNs in terms of spatially distributed patterns of correlation (typically by means of simple Pearson's coefficients) and thereby confounds together amplitude information of oscillatory activity and noise. ICA and other regression techniques, on the other hand, retain magnitude information and therefore can be sensitive to both changes in the spatially distributed nature of correlations (differences in the spatial pattern or "shape") as well as the amplitude of the network activity. Furthermore, motion can mimic amplitude effects so it is crucial to use a technique that retains such information to ensure that connectivity differences are accurately localized. In this work, we investigate the dual regression approach that is frequently applied with group ICA to assess group differences in resting state functional connectivity of brain networks. We show how ignoring amplitude effects and how excessive motion corrupts connectivity maps and results in spurious connectivity differences. We also show how to implement the dual regression to retain amplitude information and how to use dual regression outputs to identify potential motion effects. Two key findings are that using a technique that retains magnitude information, e.g., dual regression, and using strict motion criteria are crucial for controlling both network amplitude and motion-related amplitude effects

  12. Cold-Regulated Cereal Chloroplast Late Embryogenesis Abundant-Like Proteins. Molecular Characterization and Functional Analyses

    PubMed Central

    NDong, Christian; Danyluk, Jean; Wilson, Kenneth E.; Pocock, Tessa; Huner, Norman P.A.; Sarhan, Fathey

    2002-01-01

    Cold acclimation and freezing tolerance are the result of complex interaction between low temperature, light, and photosystem II (PSII) excitation pressure. Previous results have shown that expression of the Wcs19 gene is correlated with PSII excitation pressure measured in vivo as the relative reduction state of PSII. Using cDNA library screening and data mining, we have identified three different groups of proteins, late embryogenesis abundant (LEA) 3-L1, LEA3-L2, and LEA3-L3, sharing identities with WCS19. These groups represent a new class of proteins in cereals related to group 3 LEA proteins. They share important characteristics such as a sorting signal that is predicted to target them to either the chloroplast or mitochondria and a C-terminal sequence that may be involved in oligomerization. The results of subcellular fractionation, immunolocalization by electron microscopy and the analyses of target sequences within the Wcs19 gene are consistent with the localization of WCS19 within the chloroplast stroma of wheat (Triticum aestivum) and rye (Secale cereale). Western analysis showed that the accumulation of chloroplastic LEA3-L2 proteins is correlated with the capacity of different wheat and rye cultivars to develop freezing tolerance. Arabidopsis was transformed with the Wcs19 gene and the transgenic plants showed a significant increase in their freezing tolerance. This increase was only evident in cold-acclimated plants. The putative function of this protein in the enhancement of freezing tolerance is discussed. PMID:12114590

  13. Molecular and functional analyses of the contractile apparatus in lymphatic muscle

    NASA Technical Reports Server (NTRS)

    Muthuchamy, Mariappan; Gashev, Anatoliy; Boswell, Niven; Dawson, Nancy; Zawieja, David; Delp, Z. (Principal Investigator)

    2003-01-01

    Lymphatics are necessary for the generation and regulation of lymph flow. Lymphatics use phasic contractions and extrinsic compressions to generate flow; tonic contractions alter resistance. Lymphatic muscle exhibits important differences from typical vascular smooth muscle. In this study, the thoracic duct exhibited significant functional differences from mesenteric lymphatics. To understand the molecular basis for these differences, we examined the profiles of contractile proteins and their messages in mesenteric lymphatics, thoracic duct, and arterioles. Results demonstrated that mesenteric lymphatics express only SMB smooth muscle myosin heavy chain (SM-MHC), whereas thoracic duct and arterioles expressed both SMA and SMB isoforms. Both SM1 and SM2 isoforms of SM-MHC were detected in arterioles and mesenteric and thoracic lymphatics. In addition, the fetal cardiac/skeletal slow-twitch muscle-specific beta-MHC message was detected only in mesenteric lymphatics. All four actin messages, cardiac alpha-actin, vascular alpha-actin, enteric gamma-actin, and skeletal alpha-actin, were present in both mesenteric lymphatics and arterioles. However, in thoracic duct, predominantly cardiac alpha-actin and vascular alpha-actin were found. Western blot and immunohistochemical analyses corroborated the mRNA studies. However, in arterioles only vascular alpha-actin protein was detected. These data indicate that lymphatics display genotypic and phenotypic characteristics of vascular, cardiac, and visceral myocytes, which are needed to fulfill the unique roles of the lymphatic system.

  14. Simultaneous Extraction from Bacterioplankton of Total RNA and DNA Suitable for Quantitative Structure and Function Analyses

    PubMed Central

    Weinbauer, Markus G.; Fritz, Ingo; Wenderoth, Dirk F.; Höfle, Manfred G.

    2002-01-01

    The aim of this study was to develop a protocol for the simultaneous extraction from bacterioplankton of RNA and DNA suitable for quantitative molecular analysis. By using a combined mechanical and chemical extraction method, the highest RNA and DNA yield was obtained with sodium lauryl sarcosinate-phenol or DivoLab-phenol as the extraction mix. The efficiency of extraction of nucleic acids was comparatively high and varied only moderately in gram-negative bacterial isolates and bacterioplankton (RNA, 52 to 66%; DNA, 43 to 61%); significant amounts of nucleic acids were also obtained for a gram-positive bacterial isolate (RNA, 20 to 30%; DNA, 20 to 25%). Reverse transcription-PCR and PCR amplification products of fragments of 16S rRNA and its genes were obtained from all isolates and communities, indicating that the extracted nucleic acids were intact and pure enough for community structure analyses. By using single-strand conformation polymorphism of fragments of 16S rRNA and its gene, community fingerprints were obtained from pond bacterioplankton. mRNA transcripts encoding fragments of the enzyme nitrite reductase gene (nir gene) could be detected in a pond water sample, indicating that the extraction method is also suitable for studying gene expression. The extraction method presented yields nucleic acids that can be used to perform structural and functional studies of bacterioplankton communities from a single sample. PMID:11872453

  15. Model-based neuroimaging for cognitive computing.

    PubMed

    Poznanski, Roman R

    2009-09-01

    The continuity of the mind is suggested to mean the continuous spatiotemporal dynamics arising from the electrochemical signature of the neocortex: (i) globally through volume transmission in the gray matter as fields of neural activity, and (ii) locally through extrasynaptic signaling between fine distal dendrites of cortical neurons. If the continuity of dynamical systems across spatiotemporal scales defines a stream of consciousness then intentional metarepresentations as templates of dynamic continuity allow qualia to be semantically mapped during neuroimaging of specific cognitive tasks. When interfaced with a computer, such model-based neuroimaging requiring new mathematics of the brain will begin to decipher higher cognitive operations not possible with existing brain-machine interfaces.

  16. Multimodal neuroimaging based classification of autism spectrum disorder using anatomical, neurochemical, and white matter correlates

    PubMed Central

    Libero, Lauren E.; DeRamus, Thomas P.; Lahti, Adrienne C.; Deshpande, Gopikrishna; Kana, Rajesh K.

    2016-01-01

    Neuroimaging techniques, such as fMRI, structural MRI, diffusion tensor imaging (DTI), and proton magnetic resonance spectroscopy (1H-MRS) have uncovered evidence for widespread functional and anatomical brain abnormalities in autism spectrum disorder (ASD) suggesting it to be a system-wide neural systems disorder. Nevertheless, most previous studies have focused on examining one index of neuropathology through a single neuroimaging modality, and seldom using multiple modalities to examine the same cohort of individuals. The current study aims to bring together multiple brain imaging modalities (structural MRI, DTI, and 1H-MRS) to investigate the neural architecture in the same set of individuals (19 high-functioning adults with ASD and 18 typically developing (TD) peers). Morphometry analysis revealed increased cortical thickness in ASD participants, relative to typical controls, across the left cingulate, left pars opercularis of the inferior frontal gyrus, left inferior temporal cortex, and right precuneus, and reduced cortical thickness in right cuneus and right precentral gyrus. ASD adults also had reduced fractional anisotropy (FA) and increased radial diffusivity (RD) for two clusters on the forceps minor of the corpus callosum, revealed by DTI analyses. 1H-MRS results showed a reduction in the N-acetylaspartate/Creatine ratio in dorsal anterior cingulate cortex (dACC) in ASD participants. A decision tree classification analysis across the three modalities resulted in classification accuracy of 91.9% with FA, RD, and cortical thickness as key predictors. Examining the same cohort of adults with ASD and their TD peers, this study found alterations in cortical thickness, white matter (WM) connectivity, and neurochemical concentration in ASD. These findings underscore the potential for multimodal imaging to better inform on the neural characteristics most relevant to the disorder. PMID:25797658

  17. Heritability and Genetic Association Analysis of Neuroimaging Measures in the Diabetes Heart Study

    PubMed Central

    Raffield, Laura M; Cox, Amanda J; Hugenschmidt, Christina E; Freedman, Barry I; Langefeld, Carl D; Williamson, Jeff D; Hsu, Fang-Chi; Maldjian, Joseph A; Bowden, Donald W

    2014-01-01

    Patients with type 2 diabetes are at increased risk of age-related cognitive decline and dementia. Neuroimaging measures such as white matter lesion volume, brain volume, and fractional anisotropy may reflect the pathogenesis of these cognitive declines, and genetic factors may contribute to variability in these measures. This study examined multiple neuroimaging measures in 465 participants from 238 families with extensive genotype data in the type 2 diabetes enriched Diabetes Heart Study-Mind cohort. Heritability of these phenotypes and their association with candidate single nucleotide polymorphisms (SNPs) and SNP data from genome-and exome-wide arrays was explored. All neuroimaging measures analysed were significantly heritable (ĥ2 =0.55–0.99 in unadjusted models). Seventeen candidate SNPs (from 16 genes/regions) associated with neuroimaging phenotypes in prior studies showed no significant evidence of association. A missense variant (rs150706952, A432V) in PLEKHG4B from the exome-wide array was significantly associated with white matter mean diffusivity (p=3.66×10−7) and gray matter mean diffusivity (p=2.14×10−7). This analysis suggests genetic factors contribute to variation in neuroimaging measures in a population enriched for metabolic disease and other associated comorbidities. PMID:25523635

  18. Functional assays and metagenomic analyses reveals differences between the microbial communities inhabiting the soil horizons of a Norway spruce plantation.

    PubMed

    Uroz, Stéphane; Ioannidis, Panos; Lengelle, Juliette; Cébron, Aurélie; Morin, Emmanuelle; Buée, Marc; Martin, Francis

    2013-01-01

    In temperate ecosystems, acidic forest soils are among the most nutrient-poor terrestrial environments. In this context, the long-term differentiation of the forest soils into horizons may impact the assembly and the functions of the soil microbial communities. To gain a more comprehensive understanding of the ecology and functional potentials of these microbial communities, a suite of analyses including comparative metagenomics was applied on independent soil samples from a spruce plantation (Breuil-Chenue, France). The objectives were to assess whether the decreasing nutrient bioavailability and pH variations that naturally occurs between the organic and mineral horizons affects the soil microbial functional biodiversity. The 14 Gbp of pyrosequencing and Illumina sequences generated in this study revealed complex microbial communities dominated by bacteria. Detailed analyses showed that the organic soil horizon was significantly enriched in sequences related to Bacteria, Chordata, Arthropoda and Ascomycota. On the contrary the mineral horizon was significantly enriched in sequences related to Archaea. Our analyses also highlighted that the microbial communities inhabiting the two soil horizons differed significantly in their functional potentials according to functional assays and MG-RAST analyses, suggesting a functional specialisation of these microbial communities. Consistent with this specialisation, our shotgun metagenomic approach revealed a significant increase in the relative abundance of sequences related glycoside hydrolases in the organic horizon compared to the mineral horizon that was significantly enriched in glycoside transferases. This functional stratification according to the soil horizon was also confirmed by a significant correlation between the functional assays performed in this study and the functional metagenomic analyses. Together, our results suggest that the soil stratification and particularly the soil resource availability impact the

  19. Neuroimaging and Fetal Alcohol Spectrum Disorders

    ERIC Educational Resources Information Center

    Norman, Andria L.; Crocker, Nicole; Mattson, Sarah N.; Riley, Edward P.

    2009-01-01

    The detrimental effects of prenatal alcohol exposure on the developing brain include structural brain anomalies as well as cognitive and behavioral deficits. Initial neuroimaging studies of fetal alcohol spectrum disorders (FASD) using magnetic resonance imaging (MRI) confirmed previous autopsy reports of overall reduction in brain volume and…

  20. Neuroimaging studies of aggressive and violent behavior: current findings and implications for criminology and criminal justice.

    PubMed

    Bufkin, Jana L; Luttrell, Vickie R

    2005-04-01

    With the availability of new functional and structural neuroimaging techniques, researchers have begun to localize brain areas that may be dysfunctional in offenders who are aggressive and violent. Our review of 17 neuroimaging studies reveals that the areas associated with aggressive and/or violent behavioral histories, particularly impulsive acts, are located in the prefrontal cortex and the medial temporal regions. These findings are explained in the context of negative emotion regulation, and suggestions are provided concerning how such findings may affect future theoretical frameworks in criminology, crime prevention efforts, and the functioning of the criminal justice system.

  1. Behavioral, computational, and neuroimaging studies of acquired apraxia of speech

    PubMed Central

    Ballard, Kirrie J.; Tourville, Jason A.; Robin, Donald A.

    2014-01-01

    A critical examination of speech motor control depends on an in-depth understanding of network connectivity associated with Brodmann areas 44 and 45 and surrounding cortices. Damage to these areas has been associated with two conditions—the speech motor programming disorder apraxia of speech (AOS) and the linguistic/grammatical disorder of Broca’s aphasia. Here we focus on AOS, which is most commonly associated with damage to posterior Broca’s area (BA) and adjacent cortex. We provide an overview of our own studies into the nature of AOS, including behavioral and neuroimaging methods, to explore components of the speech motor network that are associated with normal and disordered speech motor programming in AOS. Behavioral, neuroimaging, and computational modeling studies are indicating that AOS is associated with impairment in learning feedforward models and/or implementing feedback mechanisms and with the functional contribution of BA6. While functional connectivity methods are not yet routinely applied to the study of AOS, we highlight the need for focusing on the functional impact of localized lesions throughout the speech network, as well as larger scale comparative studies to distinguish the unique behavioral and neurological signature of AOS. By coupling these methods with neural network models, we have a powerful set of tools to improve our understanding of the neural mechanisms that underlie AOS, and speech production generally. PMID:25404911

  2. The Cerebellum and Addiction: Insights Gained from Neuroimaging Research

    PubMed Central

    Moulton, Eric A; Elman, Igor; Becerra, Lino R; Goldstein, Rita Z; Borsook, David

    2013-01-01

    Although cerebellar alterations have been consistently noted in the addiction literature, the pathophysiology of this link remains unclear. The cerebellum is commonly classified as a motor structure, but human functional neuroimaging along with clinical observations in cerebellar stroke patients and anatomical tract tracing in non-human primates suggest its involvement in cognitive and affective processing. A comprehensive literature search on the role of the cerebellum in addiction was performed. This review article (1) considers the potential role of the cerebellum in addiction, (2) summarizes the cerebellar structural alterations linked to addiction, (3) presents the functional neuroimaging evidence linking the cerebellum with addiction, and (4) proposes a model for addiction that underscores the role of the cerebellum. The data implicate the cerebellum as an intermediary between motor and reward, motivation and cognitive control systems, as all are relevant etiologic factors in addiction. Furthermore, consideration of these findings could contribute to deeper and more sophisticated insights into normal reward and motivational function. The goal of this review is to spread awareness of cerebellar involvement in addictive processes, and to suggest a preliminary model for its potential role. PMID:24851284

  3. Real-World Neuroimaging Technologies

    DTIC Science & Technology

    2013-05-10

    Voinescu, and S. Fazli, ‘‘Bristle-sensors–low-cost flexi- ble passive dry EEG electrodes for neurofeedback and BCI applications,’’ J. Neural Eng., vol...techniques (e.g., electroencephalography [ EEG ], functional magnetic resonance imaging, functional near-infrared spectroscopy, magnetoencephalography...collection and integration, a laboratory grade, dry electrode, wirelesss, high resolution EEG system, a Bioharness 3, and an Affectiva Qsensor. Android

  4. Multivariate and repeated measures (MRM): A new toolbox for dependent and multimodal group-level neuroimaging data

    PubMed Central

    McFarquhar, Martyn; McKie, Shane; Emsley, Richard; Suckling, John; Elliott, Rebecca; Williams, Stephen

    2016-01-01

    Repeated measurements and multimodal data are common in neuroimaging research. Despite this, conventional approaches to group level analysis ignore these repeated measurements in favour of multiple between-subject models using contrasts of interest. This approach has a number of drawbacks as certain designs and comparisons of interest are either not possible or complex to implement. Unfortunately, even when attempting to analyse group level data within a repeated-measures framework, the methods implemented in popular software packages make potentially unrealistic assumptions about the covariance structure across the brain. In this paper, we describe how this issue can be addressed in a simple and efficient manner using the multivariate form of the familiar general linear model (GLM), as implemented in a new MATLAB toolbox. This multivariate framework is discussed, paying particular attention to methods of inference by permutation. Comparisons with existing approaches and software packages for dependent group-level neuroimaging data are made. We also demonstrate how this method is easily adapted for dependency at the group level when multiple modalities of imaging are collected from the same individuals. Follow-up of these multimodal models using linear discriminant functions (LDA) is also discussed, with applications to future studies wishing to integrate multiple scanning techniques into investigating populations of interest. PMID:26921716

  5. Neuromarketing: the hope and hype of neuroimaging in business.

    PubMed

    Ariely, Dan; Berns, Gregory S

    2010-04-01

    The application of neuroimaging methods to product marketing - neuromarketing - has recently gained considerable popularity. We propose that there are two main reasons for this trend. First, the possibility that neuroimaging will become cheaper and faster than other marketing methods; and second, the hope that neuroimaging will provide marketers with information that is not obtainable through conventional marketing methods. Although neuroimaging is unlikely to be cheaper than other tools in the near future, there is growing evidence that it may provide hidden information about the consumer experience. The most promising application of neuroimaging methods to marketing may come before a product is even released - when it is just an idea being developed.

  6. Multiple brain atlas database and atlas-based neuroimaging system.

    PubMed

    Nowinski, W L; Fang, A; Nguyen, B T; Raphel, J K; Jagannathan, L; Raghavan, R; Bryan, R N; Miller, G A

    1997-01-01

    For the purpose of developing multiple, complementary, fully labeled electronic brain atlases and an atlas-based neuroimaging system for analysis, quantification, and real-time manipulation of cerebral structures in two and three dimensions, we have digitized, enhanced, segmented, and labeled the following print brain atlases: Co-Planar Stereotaxic Atlas of the Human Brain by Talairach and Tournoux, Atlas for Stereotaxy of the Human Brain by Schaltenbrand and Wahren, Referentially Oriented Cerebral MRI Anatomy by Talairach and Tournoux, and Atlas of the Cerebral Sulci by Ono, Kubik, and Abernathey. Three-dimensional extensions of these atlases have been developed as well. All two- and three-dimensional atlases are mutually preregistered and may be interactively registered with an actual patient's data. An atlas-based neuroimaging system has been developed that provides support for reformatting, registration, visualization, navigation, image processing, and quantification of clinical data. The anatomical index contains about 1,000 structures and over 400 sulcal patterns. Several new applications of the brain atlas database also have been developed, supported by various technologies such as virtual reality, the Internet, and electronic publishing. Fusion of information from multiple atlases assists the user in comprehensively understanding brain structures and identifying and quantifying anatomical regions in clinical data. The multiple brain atlas database and atlas-based neuroimaging system have substantial potential impact in stereotactic neurosurgery and radiotherapy by assisting in visualization and real-time manipulation in three dimensions of anatomical structures, in quantitative neuroradiology by allowing interactive analysis of clinical data, in three-dimensional neuroeducation, and in brain function studies.

  7. The 100 most-cited articles in neuroimaging: A bibliometric analysis.

    PubMed

    Kim, Hye Jeong; Yoon, Dae Young; Kim, Eun Soo; Lee, Kwanseop; Bae, Jong Seok; Lee, Ju-Hun

    2016-06-18

    The purpose of our study was to identify and characterize the 100 most-cited articles in neuroimaging. Based on the database of Journal Citation Reports, we selected 669 journals that were considered as potential outlets for neuroimaging articles. The Web of Science search tools were used to identify the 100 most-cited articles relevant to neuroimaging within the selected journals. The following information was recorded for each article: publication year, journal, category and impact factor of journal, number of citations, number of annual citations, authorship, department, institution, country, article type, imaging technique used, and topic. The 100 most-cited articles in neuroimaging were published between 1980 and 2012, with 1995-2004 producing 69 articles. Citations ranged from 4384 to 673 and annual citations ranged from 313.1 to 24.9. The majority of articles were published in radiology/imaging journals (n=75), originated in the United States (n=58), were original articles (n=63), used MRI as imaging modality (n=85), and dealt with imaging technique (n=45). The Oxford Centre for Functional Magnetic Resonance Imaging of the Brain at John Radcliffe Hospital (n=10) was the leading institutions and Karl J. Friston (n=11) was the most prolific author. Our study presents a detailed list and an analysis of the 100 most-cited articles in the field of neuroimaging, which provides an insight into historical developments and allows for recognition of the important advances in this field.

  8. Integration of a neuroimaging processing pipeline into a pan-canadian computing grid

    NASA Astrophysics Data System (ADS)

    Lavoie-Courchesne, S.; Rioux, P.; Chouinard-Decorte, F.; Sherif, T.; Rousseau, M.-E.; Das, S.; Adalat, R.; Doyon, J.; Craddock, C.; Margulies, D.; Chu, C.; Lyttelton, O.; Evans, A. C.; Bellec, P.

    2012-02-01

    The ethos of the neuroimaging field is quickly moving towards the open sharing of resources, including both imaging databases and processing tools. As a neuroimaging database represents a large volume of datasets and as neuroimaging processing pipelines are composed of heterogeneous, computationally intensive tools, such open sharing raises specific computational challenges. This motivates the design of novel dedicated computing infrastructures. This paper describes an interface between PSOM, a code-oriented pipeline development framework, and CBRAIN, a web-oriented platform for grid computing. This interface was used to integrate a PSOM-compliant pipeline for preprocessing of structural and functional magnetic resonance imaging into CBRAIN. We further tested the capacity of our infrastructure to handle a real large-scale project. A neuroimaging database including close to 1000 subjects was preprocessed using our interface and publicly released to help the participants of the ADHD-200 international competition. This successful experiment demonstrated that our integrated grid-computing platform is a powerful solution for high-throughput pipeline analysis in the field of neuroimaging.

  9. Frontal lobe alterations in schizophrenia: neuroimaging and neuropsychological findings.

    PubMed

    de la Torre, Juan Carlos Sanz; Barrios, Maite; Junqué, Carme

    2005-08-01

    Functional neuroimaging and neuropsychological performance indicate a prefrontal dysfunction in schizophrenia patients. Frontal morphological brain abnormalities are also evident in these patients, but the relationship between neuropsychology and neuroimaging findings remains unclear. In this study, thirty patients with schizophrenia and 30 control participants were assessed using a neuropsychological test battery sensitive to fronto-striatal system dysfunction. Computed tomography (CT) scans were used to calculate the distance from the corpus callosum to the frontal pole corrected for brain size (anterioposterior length) in the group of patients and in a group of control participants with negative radiological findings. Schizophrenia patients performed significantly worse than controls in all frontal lobe tests. Corrected length from the corpus callosum to the frontal pole was reduced in patients with schizophrenia. This easy-to-perform measurement has not been used in previous studies, and indicates that schizophrenia patients have structural frontal abnormalities. However, correlations between structural and functional measures fail to show a clear relationship between the prefrontal performance and the main CT measures. As a rule, the trend observed in the correlation matrix pointed towards a relationship between CT parameters and a dysfunction on neuropsychological tests sensitive to frontal lobe damage.

  10. Neuroimaging correlates of pharmacological and psychological treatments for specific phobia.

    PubMed

    Linares, Ila M; Chags, Marcos H N; Machado-de-Sousa, João P; Crippa, José A S; Hallak, Jaime E C

    2014-01-01

    Specific phobia is an anxiety disorder characterized by irrational fear and avoidance of specific things or situations, interfering significantly with the patients' daily life. Treatment for the disorder consists of both pharmacological and psychological approaches, mainly cognitive behavioral therapy (CBT). Neuroimaging techniques have been used in an attempt to improve our understanding of the neurobiology of SP and of the effects of treatment options available. This review describes the design and results of eight articles investigating the neuroimaging correlates of pharmacological and psychological treatments for SP. The studies show that CBT is effective in SP, leading to a reduction of anxiety symptoms that is accompanied by functional alterations in the brain. The results of pharmacological interventions for SP are less uniform, but suggest that the partial agonist of the NMDA (N-methyl D-aspartate) receptor DCS (D-cycloserine) can be used in combination with psychotherapy techniques for the achievement of quicker treatment response and that DCS modulates the function of structures implicated in the neurobiology of SP. Further research should explore the augmentation of CBT treatment with DCS in controlled trials.

  11. Crucial role of detailed function, task, timeline, link and human vulnerability analyses in HRA. [Human Reliability Analysis (HRA)

    SciTech Connect

    Ryan, T.G.; Haney, L.N.; Ostrom, L.T.

    1992-01-01

    This paper addresses one major cause for large uncertainties in human reliability analysis (HRA) results, that is, an absence of detailed function, task, timeline, link and human vulnerability analyses. All too often this crucial step in the HRA process is done in a cursory fashion using word of mouth or written procedures which themselves may incompletely or inaccurately represent the human action sequences and human error vulnerabilities being analyzed. The paper examines the potential contributions these detailed analyses can make in achieving quantitative and qualitative HRA results which are: (1) creditable, that is, minimize uncertainty, (2) auditable, that is, systematically linking quantitative results and qualitative information from which the results are derived, (3) capable of supporting root cause analyses on human reliability factors determined to be major contributors to risk, and (4) capable of repeated measures and being combined with similar results from other analyses to examine HRA issues transcending individual systems and facilities. Based on experience analyzing test and commercial nuclear reactors, and medical applications of nuclear technology, an iterative process is suggested for doing detailed function, task, timeline, link and human vulnerability analyses using documentation reviews, open-ended and structured interviews, direct observations, and group techniques. Finally, the paper concludes that detailed analyses done in this manner by knowledgeable human factors practitioners, can contribute significantly to the credibility, auditability, causal factor analysis, and combining goals of the HRA.

  12. Combined Functional and Causal Connectivity Analyses of Language Networks in Children: A Feasibility Study

    ERIC Educational Resources Information Center

    Wilke, Marko; Lidzba, Karen; Krageloh-Mann, Ingeborg

    2009-01-01

    Instead of assessing activation in distinct brain regions, approaches to investigating the networks underlying distinct brain functions have come into the focus of neuroscience research. Here, we provide a completely data-driven framework for assessing functional and causal connectivity in functional magnetic resonance imaging (fMRI) data,…

  13. Meta-Analyses of Ethnic Match as a Predictor of Dropout, Utilization, and Level of Functioning.

    ERIC Educational Resources Information Center

    Maramba, Gloria Gia; Hall, Gordon C. Nagayama

    2002-01-01

    Meta-analyses were performed on seven studies of ethnic match and psychotherapy. Results reveal a small dropout and utilization effect sizes, indicating that ethnic match is not a significant clinical predictor of decreasing dropout after the first session or increasing number of sessions attended. (Contains references and tables.) (GCP)

  14. Neuroimaging and genetic risk for Alzheimer's disease and addiction-related degenerative brain disorders.

    PubMed

    Roussotte, Florence F; Daianu, Madelaine; Jahanshad, Neda; Leonardo, Cassandra D; Thompson, Paul M

    2014-06-01

    Neuroimaging offers a powerful means to assess the trajectory of brain degeneration in a variety of disorders, including Alzheimer's disease (AD). Here we describe how multi-modal imaging can be used to study the changing brain during the different stages of AD. We integrate findings from a range of studies using magnetic resonance imaging (MRI), positron emission tomography (PET), functional MRI (fMRI) and diffusion weighted imaging (DWI). Neuroimaging reveals how risk genes for degenerative disorders affect the brain, including several recently discovered genetic variants that may disrupt brain connectivity. We review some recent neuroimaging studies of genetic polymorphisms associated with increased risk for late-onset Alzheimer's disease (LOAD). Some genetic variants that increase risk for drug addiction may overlap with those associated with degenerative brain disorders. These common associations offer new insight into mechanisms underlying neurodegeneration and addictive behaviors, and may offer new leads for treating them before severe and irreversible neurological symptoms appear.

  15. The effects of acute alcohol administration on the human brain: insights from neuroimaging.

    PubMed

    Bjork, James M; Gilman, Jodi M

    2014-09-01

    Over the last quarter century, researchers have peered into the living human brain to develop and refine mechanistic accounts of alcohol-induced behavior, as well as neurobiological mechanisms for development and maintenance of addiction. These in vivo neuroimaging studies generally show that acute alcohol administration affects brain structures implicated in motivation and behavior control, and that chronic intoxication is correlated with structural and functional abnormalities in these same structures, where some elements of these decrements normalize with extended sobriety. In this review, we will summarize recent findings about acute human brain responses to alcohol using neuroimaging techniques, and how they might explain behavioral effects of alcohol intoxication. We then briefly address how chronic alcohol intoxication (as inferred from cross-sectional differences between various drinking populations and controls) may yield individual brain differences between drinking subjects that may confound interpretation of acute alcohol administration effects. This article is part of the Special Issue Section entitled 'Neuroimaging in Neuropharmacology'.

  16. Mind-Body Practices and the Adolescent Brain: Clinical Neuroimaging Studies

    PubMed Central

    Sharma, Anup; Newberg, Andrew B

    2016-01-01

    Background Mind-Body practices constitute a large and diverse group of practices that can substantially affect neurophysiology in both healthy individuals and those with various psychiatric disorders. In spite of the growing literature on the clinical and physiological effects of mind-body practices, very little is known about their impact on central nervous system (CNS) structure and function in adolescents with psychiatric disorders. Method This overview highlights findings in a select group of mind-body practices including yoga postures, yoga breathing techniques and meditation practices. Results Mind-body practices offer novel therapeutic approaches for adolescents with psychiatric disorders. Findings from these studies provide insights into the design and implementation of neuroimaging studies for adolescents with psychiatric disorders. Conclusions Clinical neuroimaging studies will be critical in understanding how different practices affect disease pathogenesis and symptomatology in adolescents. Neuroimaging of mind-body practices on adolescents with psychiatric disorders will certainly be an open and exciting area of investigation. PMID:27347478

  17. Neuroimage evidence and the insanity defense.

    PubMed

    Schweitzer, N J; Saks, Michael J

    2011-01-01

    The introduction of neuroscientific evidence in criminal trials has given rise to fears that neuroimagery presented by an expert witness might inordinately influence jurors' evaluations of the defendant. In this experiment, a diverse sample of 1,170 community members from throughout the U.S. evaluated a written mock trial in which psychological, neuropsychological, neuroscientific, and neuroimage-based expert evidence was presented in support of a not guilty by reason of insanity (NGRI) defense. No evidence of an independent influence of neuroimagery was found. Overall, neuroscience-based evidence was found to be more persuasive than psychological and anecdotal family history evidence. These effects were consistent across different insanity standards. Despite the non-influence of neuroimagery, however, jurors who were not provided with a neuroimage indicated that they believed neuroimagery would have been the most helpful kind of evidence in their evaluations of the defendant.

  18. Inferring mental states from neuroimaging data: From reverse inference to large-scale decoding

    PubMed Central

    Poldrack, Russell A.

    2011-01-01

    A common goal of neuroimaging research is to use imaging data to identify the mental processes that are engaged when a subject performs a mental task. The use of reasoning from activation to mental functions, known as “reverse inference”, has been previously criticized on the basis that it does not take into account how selectively the area is activated by the mental process in question. In this Perspective, I outline the critique of informal reverse inference, and describe a number of new developments that provide the ability to more formally test the predictive power of neuroimaging data. PMID:22153367

  19. Deficient approaches to human neuroimaging

    PubMed Central

    Stelzer, Johannes; Lohmann, Gabriele; Mueller, Karsten; Buschmann, Tilo; Turner, Robert

    2014-01-01

    Functional magnetic resonance imaging (fMRI) is the workhorse of imaging-based human cognitive neuroscience. The use of fMRI is ever-increasing; within the last 4 years more fMRI studies have been published than in the previous 17 years. This large body of research has mainly focused on the functional localization of condition- or stimulus-dependent changes in the blood-oxygenation-level dependent signal. In recent years, however, many aspects of the commonly practiced analysis frameworks and methodologies have been critically reassessed. Here we summarize these critiques, providing an overview of the major conceptual and practical deficiencies in widely used brain-mapping approaches, and exemplify some of these issues by the use of imaging data and simulations. In particular, we discuss the inherent pitfalls and shortcomings of methodologies for statistical parametric mapping. Our critique emphasizes recent reports of excessively high numbers of both false positive and false negative findings in fMRI brain mapping. We outline our view regarding the broader scientific implications of these methodological considerations and briefly discuss possible solutions. PMID:25071503

  20. AN IMPROVED CELL ISOLATION METHOD FOR FLOW CYTOMETRIC AND FUNCTIONAL ANALYSES OF CUTANEOUS WOUND LEUKOCYTES

    PubMed Central

    Brubaker, Aleah L.; Schneider, David F.; Palmer, Jessica L.; Faunce, Douglas E.; Kovacs, Elizabeth J.

    2011-01-01

    Isolation of leukocytes from full-thickness excisional wounds has proven to be a difficult process that results in poor cell yield and holds significant limitations for functional assays. Given the increased interest in the isolation, characterization and functional measurements of wound-derived cell populations, herein we describe a method for preparing wound cell suspensions with an improved yield that enables both phenotypic and functional assessments. PMID:21889511

  1. Human auditory neuroimaging of intensity and loudness.

    PubMed

    Uppenkamp, Stefan; Röhl, Markus

    2014-01-01

    The physical intensity of a sound, usually expressed in dB on a logarithmic ratio scale, can easily be measured using technical equipment. Loudness is the perceptual correlate of sound intensity, and is usually determined by means of some sort of psychophysical scaling procedure. The interrelation of sound intensity and perceived loudness is still a matter of debate, and the physiological correlate of loudness perception in the human auditory pathway is not completely understood. Various studies indicate that the activation in human auditory cortex is more a representation of loudness sensation rather than of physical sound pressure level. This raises the questions (1), at what stage or stages in the ascending auditory pathway is the transformation of the physical stimulus into its perceptual correlate completed, and (2), to what extent other factors affecting individual loudness judgements might modulate the brain activation as registered by auditory neuroimaging. An overview is given about recent studies on the effects of sound intensity, duration, bandwidth and individual hearing status on the activation in the human auditory system, as measured by various approaches in auditory neuroimaging. This article is part of a Special Issue entitled Human Auditory Neuroimaging.

  2. Neuroimaging: beginning to appreciate its complexities.

    PubMed

    Parens, Erik; Johnston, Josephine

    2014-01-01

    For over a century, scientists have sought to see through the protective shield of the human skull and into the living brain. Today, an array of technologies allows researchers and clinicians to create astonishingly detailed images of our brain's structure as well as colorful depictions of the electrical and physiological changes that occur within it when we see, hear, think and feel. These technologies-and the images they generate-are an increasingly important tool in medicine and science. Given the role that neuroimaging technologies now play in biomedical research, both neuroscientists and nonexperts should aim to be as clear as possible about how neuroimages are made and what they can-and cannot-tell us. Add to this that neuroimages have begun to be used in courtrooms at both the determination of guilt and sentencing stages, that they are being employed by marketers to refine advertisements and develop new products, that they are being sold to consumers for the diagnosis of mental disorders and for the detection of lies, and that they are being employed in arguments about the nature (or absence) of powerful concepts like free will and personhood, and the need for citizens to have a basic understanding of how this technology works and what it can and cannot tell us becomes even more pressing.

  3. Implementation and Validation of Trial-Based Functional Analyses in Public Elementary School Settings

    ERIC Educational Resources Information Center

    Lloyd, Blair P.; Wehby, Joseph H.; Weaver, Emily S.; Goldman, Samantha E.; Harvey, Michelle N.; Sherlock, Daniel R.

    2015-01-01

    Although functional analysis (FA) remains the standard for identifying the function of problem behavior for students with developmental disabilities, traditional FA procedures are typically costly in terms of time, resources, and perceived risks. Preliminary research suggests that trial-based FA may be a less costly alternative. The purpose of…

  4. Teacher-Conducted Trial-Based Functional Analyses as the Basis for Intervention

    ERIC Educational Resources Information Center

    Bloom, Sarah E.; Lambert, Joseph M.; Dayton, Elizabeth; Samaha, Andrew L.

    2013-01-01

    Previous studies have focused on whether a trial-based functional analysis (FA) yields the same outcomes as more traditional FAs, and whether interventions based on trial-based FAs can reduce socially maintained problem behavior. We included a full range of behavior functions and taught 3 teachers to conduct a trial-based FA with 3 boys with…

  5. Comparison of Traditional and Trial-Based Methodologies for Conducting Functional Analyses

    ERIC Educational Resources Information Center

    LaRue, Robert H.; Lenard, Karen; Weiss, Mary Jane; Bamond, Meredith; Palmieri, Mark; Kelley, Michael E.

    2010-01-01

    Functional analysis represents a sophisticated and empirically supported functional assessment procedure. While these procedures have garnered considerable empirical support, they are often underused in clinical practice. Safety risks resulting from the evocation of maladaptive behavior and the length of time required to conduct functional…

  6. Integrating Genetic, Psychopharmacological and Neuroimaging Studies: A Converging Methods Approach to Understanding the Neurobiology of ADHD

    ERIC Educational Resources Information Center

    Durston, Sarah; Konrad, Kerstin

    2007-01-01

    This paper aims to illustrate how combining multiple approaches can inform us about the neurobiology of ADHD. Converging evidence from genetic, psychopharmacological and functional neuroimaging studies has implicated dopaminergic fronto-striatal circuitry in ADHD. However, while the observation of converging evidence from multiple vantage points…

  7. Neuroimaging procedures and related acquisitions in bipolar disorder: state of the art.

    PubMed

    Dell'Osso, Bernardo; Dobrea, Cristina; Palazzo, Maria Carlotta; Cremaschi, Laura; Penzo, Beatrice; Benatti, Beatrice; Camuri, Giulia; Arici, Chiara; Suppes, Trisha; Altamura, A Carlo

    2014-01-01

    Bipolar disorder (BD) is a chronic and disabling mood disorder, with significant suicide rates among psychiatric disorders. Although the pathophysiological bases of BD have not been fully elucidated yet, over the last two decades, neuroimaging research has documented specific neuroanatomic and functional abnormalities in bipolar patients. The present review was aimed to provide an updated and comprehensive overview about currently available evidence on main structural and functional alterations documented in BD by neuroimaging procedures, through a Medline research. Among the structural alterations, the most consistent ones seem to be at the level of frontal, temporal and insular cortices, amygdala and basal ganglia, having been ventriculomegaly reported as well. Magnetic resonance spectroscopy findings showed, in turn, biochemical alterations in several neurotransmitter systems. Functional neuroimaging data are quite heterogeneous with positron emission tomography and single photon emission computed tomography studies showing phase-specific abnormalities of blood flow and glucose metabolism, as well as modifications of serotonin transporter density and binding. Functional magnetic resonance imaging data documented impaired neural networks involved in emotional regulation, including anterior limbic, ventral and dorsal prefrontal regions. Taken as a whole, neuroimaging data are strongly advancing the understanding of the neural bases of BD as described in the present review.

  8. What have we learned about cognitive development from neuroimaging?

    PubMed

    Durston, Sarah; Casey, B J

    2006-01-01

    Changes in many domains of cognition occur with development. In this paper, we discuss neuroimaging approaches to understanding these changes at a neural level. We highlight how modern imaging methods such as functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) are being used to examine how cognitive development is supported by the maturation of the brain. Some reports suggest developmental changes in patterns of brain activity appear to involve a shift from diffuse to more focal activation, likely representing a fine-tuning of relevant neural systems with experience. One of the challenges in investigating the interplay between cognitive development and maturation of the brain is to separate the contributions of neural changes specific to development and learning. Examples are given from the developmental neuroimaging literature. The focus is on the development of cognitive control, as the protracted developmental course of this ability into adolescence raises key issues. Finally, the relevance of normative studies for understanding neural and cognitive changes in developmental disorders is discussed.

  9. Self-development: integrating cognitive, socioemotional, and neuroimaging perspectives.

    PubMed

    Pfeifer, Jennifer H; Peake, Shannon J

    2012-01-01

    This review integrates cognitive, socioemotional, and neuroimaging perspectives on self-development. Neural correlates of key processes implicated in personal and social identity are reported from studies of children, adolescents, and adults, including autobiographical memory, direct and reflected self-appraisals, and social exclusion. While cortical midline structures of medial prefrontal cortex and medial posterior parietal cortex are consistently identified in neuroimaging studies considering personal identity from a primarily cognitive perspective ("who am I?"), additional regions are implicated by studies considering personal and social identity from a more socioemotional perspective ("what do others think about me, where do I fit in?"), especially in child or adolescent samples. The involvement of these additional regions (including tempo-parietal junction and posterior superior temporal sulcus, temporal poles, anterior insula, ventral striatum, anterior cingulate cortex, middle cingulate cortex, and ventrolateral prefrontal cortex) suggests mentalizing, emotion, and emotion regulation are central to self-development. In addition, these regions appear to function atypically during personal and social identity tasks in autism and depression, exhibiting a broad pattern of hypoactivation and hyperactivation, respectively.

  10. Understanding face perception by means of prosopagnosia and neuroimaging.

    PubMed

    Rossion, Bruno

    2014-06-01

    Understanding the human neuro-anatomy of face recognition is a long-standing goal of Cognitive Neuroscience. Studies of patients with face recognition impairment following brain damage (i.e., acquired prosopagnosia) have revealed the specificity of face recognition, the importance and nature of holistic/configural perception of individual faces, and the distribution of this function in the ventral occipito-temporal (VOT) cortex, with a right hemispheric dominance. Yet, neuroimaging studies in this field have essentially focused on a single face-selective area of the VOT and underestimated the right hemisphere superiority. Findings in these studies have also been taken as supporting a hierarchical view of face perception, according to which a face is decomposed into parts in early face-selective areas, these parts being subsequently integrated into a whole representation in higher-order areas. This review takes a historical and current perspective on the study of acquired prosopagnosia and neuroimaging that challenges this latter view. It argues for a combination of these methods, an approach suggesting a coarse-to-fine emergence of the holistic face percept in a non-hierarchical network of cortical face-selective areas.

  11. Bioinformatics and functional analyses of coronavirus nonstructural proteins involved in the formation of replicative organelles.

    PubMed

    Neuman, Benjamin W

    2016-11-01

    Replication of eukaryotic positive-stranded RNA viruses is usually linked to the presence of membrane-associated replicative organelles. The purpose of this review is to discuss the function of proteins responsible for formation of the coronavirus replicative organelle. This will be done by identifying domains that are conserved across the order Nidovirales, and by summarizing what is known about function and structure at the level of protein domains.

  12. Functional Analyses of Bitter Taste Receptors in Domestic Cats (Felis catus)

    PubMed Central

    Lei, Weiwei; Ravoninjohary, Aurore; Li, Xia; Margolskee, Robert F.; Reed, Danielle R.; Beauchamp, Gary K.; Jiang, Peihua

    2015-01-01

    Cats are obligate carnivores and under most circumstances eat only animal products. Owing to the pseudogenization of one of two subunits of the sweet receptor gene, they are indifferent to sweeteners, presumably having no need to detect plant-based sugars in their diet. Following this reasoning and a recent report of a positive correlation between the proportion of dietary plants and the number of Tas2r (bitter receptor) genes in vertebrate species, we tested the hypothesis that if bitter perception exists primarily to protect animals from poisonous plant compounds, the genome of the domestic cat (Felis catus) should have lost functional bitter receptors and they should also have reduced bitter receptor function. To test functionality of cat bitter receptors, we expressed cat Tas2R receptors in cell-based assays. We found that they have at least 7 functional receptors with distinct receptive ranges, showing many similarities, along with some differences, with human bitter receptors. To provide a comparative perspective, we compared the cat repertoire of intact receptors with those of a restricted number of members of the order Carnivora, with a range of dietary habits as reported in the literature. The numbers of functional bitter receptors in the terrestrial Carnivora we examined, including omnivorous and herbivorous species, were roughly comparable to that of cats thereby providing no strong support for the hypothesis that a strict meat diet influences bitter receptor number or function. Maintenance of bitter receptor function in terrestrial obligate carnivores may be due to the presence of bitter compounds in vertebrate and invertebrate prey, to the necessary role these receptors play in non-oral perception, or to other unknown factors. We also found that the two aquatic Carnivora species examined had fewer intact bitter receptors. Further comparative studies of factors driving numbers and functions of bitter taste receptors will aid in understanding the forces

  13. Cross-biome metagenomic analyses of soil microbial communities and their functional attributes.

    PubMed

    Fierer, Noah; Leff, Jonathan W; Adams, Byron J; Nielsen, Uffe N; Bates, Scott Thomas; Lauber, Christian L; Owens, Sarah; Gilbert, Jack A; Wall, Diana H; Caporaso, J Gregory

    2012-12-26

    For centuries ecologists have studied how the diversity and functional traits of plant and animal communities vary across biomes. In contrast, we have only just begun exploring similar questions for soil microbial communities despite soil microbes being the dominant engines of biogeochemical cycles and a major pool of living biomass in terrestrial ecosystems. We used metagenomic sequencing to compare the composition and functional attributes of 16 soil microbial communities collected from cold deserts, hot deserts, forests, grasslands, and tundra. Those communities found in plant-free cold desert soils typically had the lowest levels of functional diversity (diversity of protein-coding gene categories) and the lowest levels of phylogenetic and taxonomic diversity. Across all soils, functional beta diversity was strongly correlated with taxonomic and phylogenetic beta diversity; the desert microbial communities were clearly distinct from the nondesert communities regardless of the metric used. The desert communities had higher relative abundances of genes associated with osmoregulation and dormancy, but lower relative abundances of genes associated with nutrient cycling and the catabolism of plant-derived organic compounds. Antibiotic resistance genes were consistently threefold less abundant in the desert soils than in the nondesert soils, suggesting that abiotic conditions, not competitive interactions, are more important in shaping the desert microbial communities. As the most comprehensive survey of soil taxonomic, phylogenetic, and functional diversity to date, this study demonstrates that metagenomic approaches can be used to build a predictive understanding of how microbial diversity and function vary across terrestrial biomes.

  14. Comparative transcriptome analyses of seven anurans reveal functions and adaptations of amphibian skin

    PubMed Central

    Huang, Li; Li, Jun; Anboukaria, Housseni; Luo, Zhenhua; Zhao, Mian; Wu, Hua

    2016-01-01

    Animal skin, which is the tissue that directly contacts the external surroundings, has evolved diverse functions to adapt to various environments. Amphibians represent the transitional taxon from aquatic to terrestrial life. Exploring the molecular basis of their skin function and adaptation is important to understand the survival and evolutionary mechanisms of vertebrates. However, comprehensive studies on the molecular mechanisms of skin functions in amphibians are scarce. In this study, we sequenced the skin transcriptomes of seven anurans belonging to three families and compared the similarities and differences in expressed genes and proteins. Unigenes and pathways related to basic biological processes and special functions, such as defense, immunity, and respiration, were enriched in functional annotations. A total of 108 antimicrobial peptides were identified. The highly expressed genes were similar in species of the same family but were different among families. Additionally, the positively selected orthologous groups were involved in biosynthesis, metabolism, immunity, and defense processes. This study is the first to generate extensive transcriptome data for the skin of seven anurans and provides unigenes and pathway candidates for further studies on amphibian skin function and adaptation. PMID:27040083

  15. In actio optophysiological analyses reveal functional diversification of dopaminergic neurons in the nematode C. elegans

    NASA Astrophysics Data System (ADS)

    Tanimoto, Yuki; Zheng, Ying Grace; Fei, Xianfeng; Fujie, Yukako; Hashimoto, Koichi; Kimura, Koutarou D.

    2016-05-01

    Many neuronal groups such as dopamine-releasing (dopaminergic) neurons are functionally divergent, although the details of such divergence are not well understood. Dopamine in the nematode Caenorhabditis elegans modulates various neural functions and is released from four left-right pairs of neurons. The terminal identities of these dopaminergic neurons are regulated by the same genetic program, and previous studies have suggested that they are functionally redundant. In this study, however, we show functional divergence within the dopaminergic neurons of C. elegans. Because dopaminergic neurons of the animals were supposedly activated by mechanical stimulus upon entry into a lawn of their food bacteria, we developed a novel integrated microscope system that can auto-track a freely-moving (in actio) C. elegans to individually monitor and stimulate the neuronal activities of multiple neurons. We found that only head-dorsal pair of dopaminergic neurons (CEPD), but not head-ventral or posterior pairs, were preferentially activated upon food entry. In addition, the optogenetic activation of CEPD neurons alone exhibited effects similar to those observed upon food entry. Thus, our results demonstrated functional divergence in the genetically similar dopaminergic neurons, which may provide a new entry point toward understanding functional diversity of neurons beyond genetic terminal identification.

  16. A review of longitudinal electroconvulsive therapy: neuroimaging investigations.

    PubMed

    Abbott, Christopher C; Gallegos, Patrick; Rediske, Nathan; Lemke, Nicholas T; Quinn, Davin K

    2014-03-01

    Electroconvulsive therapy (ECT) is the most effective treatment for a depressive episode but the mechanism of action and neural correlates of response are poorly understood. Different theories have suggested that anticonvulsant properties or neurotrophic effects are related to the unique mechanism of action of ECT. This review assessed longitudinal imaging investigations (both structural and functional) associated with ECT response published from 2002 to August 2013. We identified 26 investigations that used a variety of different imaging modalities and data analysis methods. Despite these methodological differences, we summarized the major findings of each investigation and identified common patterns that exist across multiple investigations. The ECT response is associated with decreased frontal perfusion, metabolism, and functional connectivity and increased volume and neuronal chemical metabolites. The general collective of longitudinal neuroimaging investigations support both the anticonvulsant and the neurotrophic effects of ECT. We propose a conceptual framework that integrates these seemingly contradictory hypotheses.

  17. Subshell fitting of relativistic atomic core electron densities for use in QTAIM analyses of ECP-based wave functions.

    PubMed

    Keith, Todd A; Frisch, Michael J

    2011-11-17

    Scalar-relativistic, all-electron density functional theory (DFT) calculations were done for free, neutral atoms of all elements of the periodic table using the universal Gaussian basis set. Each core, closed-subshell contribution to a total atomic electron density distribution was separately fitted to a spherical electron density function: a linear combination of s-type Gaussian functions. The resulting core subshell electron densities are useful for systematically and compactly approximating total core electron densities of atoms in molecules, for any atomic core defined in terms of closed subshells. When used to augment the electron density from a wave function based on a calculation using effective core potentials (ECPs) in the Hamiltonian, the atomic core electron densities are sufficient to restore the otherwise-absent electron density maxima at the nuclear positions and eliminate spurious critical points in the neighborhood of the atom, thus enabling quantum theory of atoms in molecules (QTAIM) analyses to be done in the neighborhoods of atoms for which ECPs were used. Comparison of results from QTAIM analyses with all-electron, relativistic and nonrelativistic molecular wave functions validates the use of the atomic core electron densities for augmenting electron densities from ECP-based wave functions. For an atom in a molecule for which a small-core or medium-core ECPs is used, simply representing the core using a simplistic, tightly localized electron density function is actually sufficient to obtain a correct electron density topology and perform QTAIM analyses to obtain at least semiquantitatively meaningful results, but this is often not true when a large-core ECP is used. Comparison of QTAIM results from augmenting ECP-based molecular wave functions with the realistic atomic core electron densities presented here versus augmenting with the limiting case of tight core densities may be useful for diagnosing the reliability of large-core ECP models in

  18. Analyses of soil microbial community compositions and functional genes reveal potential consequences of natural forest succession

    NASA Astrophysics Data System (ADS)

    Cong, Jing; Yang, Yunfeng; Liu, Xueduan; Lu, Hui; Liu, Xiao; Zhou, Jizhong; Li, Diqiang; Yin, Huaqun; Ding, Junjun; Zhang, Yuguang

    2015-05-01

    The succession of microbial community structure and function is a central ecological topic, as microbes drive the Earth’s biogeochemical cycles. To elucidate the response and mechanistic underpinnings of soil microbial community structure and metabolic potential relevant to natural forest succession, we compared soil microbial communities from three adjacent natural forests: a coniferous forest (CF), a mixed broadleaf forest (MBF) and a deciduous broadleaf forest (DBF) on Shennongjia Mountain in central China. In contrary to plant communities, the microbial taxonomic diversity of the DBF was significantly (P < 0.05) higher than those of CF and MBF, rendering their microbial community compositions markedly different. Consistently, microbial functional diversity was also highest in the DBF. Furthermore, a network analysis of microbial carbon and nitrogen cycling genes showed the network for the DBF samples was relatively large and tight, revealing strong couplings between microbes. Soil temperature, reflective of climate regimes, was important in shaping microbial communities at both taxonomic and functional gene levels. As a first glimpse of both the taxonomic and functional compositions of soil microbial communities, our results suggest that microbial community structure and function potentials will be altered by future environmental changes, which have implications for forest succession.

  19. Analyses of soil microbial community compositions and functional genes reveal potential consequences of natural forest succession

    PubMed Central

    Cong, Jing; Yang, Yunfeng; Liu, Xueduan; Lu, Hui; Liu, Xiao; Zhou, Jizhong; Li, Diqiang; Yin, Huaqun; Ding, Junjun; Zhang, Yuguang

    2015-01-01

    The succession of microbial community structure and function is a central ecological topic, as microbes drive the Earth’s biogeochemical cycles. To elucidate the response and mechanistic underpinnings of soil microbial community structure and metabolic potential relevant to natural forest succession, we compared soil microbial communities from three adjacent natural forests: a coniferous forest (CF), a mixed broadleaf forest (MBF) and a deciduous broadleaf forest (DBF) on Shennongjia Mountain in central China. In contrary to plant communities, the microbial taxonomic diversity of the DBF was significantly (P < 0.05) higher than those of CF and MBF, rendering their microbial community compositions markedly different. Consistently, microbial functional diversity was also highest in the DBF. Furthermore, a network analysis of microbial carbon and nitrogen cycling genes showed the network for the DBF samples was relatively large and tight, revealing strong couplings between microbes. Soil temperature, reflective of climate regimes, was important in shaping microbial communities at both taxonomic and functional gene levels. As a first glimpse of both the taxonomic and functional compositions of soil microbial communities, our results suggest that microbial community structure and function potentials will be altered by future environmental changes, which have implications for forest succession. PMID:25943705

  20. Analyses of soil microbial community compositions and functional genes reveal potential consequences of natural forest succession.

    PubMed

    Cong, Jing; Yang, Yunfeng; Liu, Xueduan; Lu, Hui; Liu, Xiao; Zhou, Jizhong; Li, Diqiang; Yin, Huaqun; Ding, Junjun; Zhang, Yuguang

    2015-05-06

    The succession of microbial community structure and function is a central ecological topic, as microbes drive the Earth's biogeochemical cycles. To elucidate the response and mechanistic underpinnings of soil microbial community structure and metabolic potential relevant to natural forest succession, we compared soil microbial communities from three adjacent natural forests: a coniferous forest (CF), a mixed broadleaf forest (MBF) and a deciduous broadleaf forest (DBF) on Shennongjia Mountain in central China. In contrary to plant communities, the microbial taxonomic diversity of the DBF was significantly (P < 0.05) higher than those of CF and MBF, rendering their microbial community compositions markedly different. Consistently, microbial functional diversity was also highest in the DBF. Furthermore, a network analysis of microbial carbon and nitrogen cycling genes showed the network for the DBF samples was relatively large and tight, revealing strong couplings between microbes. Soil temperature, reflective of climate regimes, was important in shaping microbial communities at both taxonomic and functional gene levels. As a first glimpse of both the taxonomic and functional compositions of soil microbial communities, our results suggest that microbial community structure and function potentials will be altered by future environmental changes, which have implications for forest succession.

  1. Functional Analyses of Human DNA Repair Proteins Important for Aging and Genomic Stability Using Yeast Genetics

    PubMed Central

    Aggarwal, Monika; Brosh, Robert M.

    2012-01-01

    Model systems have been extremely useful for studying various theories of aging. Studies of yeast have been particularly helpful to explore the molecular mechanisms and pathways that affect aging at the cellular level in the simple eukaryote. Although genetic analysis has been useful to interrogate the aging process, there has been both interest and debate over how functionally conserved the mechanisms of aging are between yeast and higher eukaryotes, especially mammalian cells. One area of interest has been the importance of genomic stability for age-related processes, and the potential conservation of proteins and pathways between yeast and human. Translational genetics have been employed to examine the functional roles of mammalian proteins using yeast as a pliable model system. In the current review recent advancements made in this area are discussed, highlighting work which shows that the cellular functions of human proteins in DNA repair and maintenance of genomic stability can be elucidated by genetic rescue experiments performed in yeast. PMID:22349084

  2. In vivo function and comparative genomic analyses of the Drosophila gut microbiota identify candidate symbiosis factors

    PubMed Central

    Newell, Peter D.; Chaston, John M.; Wang, Yiping; Winans, Nathan J.; Sannino, David R.; Wong, Adam C. N.; Dobson, Adam J.; Kagle, Jeanne; Douglas, Angela E.

    2014-01-01

    Symbiosis is often characterized by co-evolutionary changes in the genomes of the partners involved. An understanding of these changes can provide insight into the nature of the relationship, including the mechanisms that initiate and maintain an association between organisms. In this study we examined the genome sequences of bacteria isolated from the Drosophila melanogaster gut with the objective of identifying genes that are important for function in the host. We compared microbiota isolates with con-specific or closely related bacterial species isolated from non-fly environments. First the phenotype of germ-free Drosophila (axenic flies) was compared to that of flies colonized with specific bacteria (gnotobiotic flies) as a measure of symbiotic function. Non-fly isolates were functionally distinct from bacteria isolated from flies, conferring slower development and an altered nutrient profile in the host, traits known to be microbiota-dependent. Comparative genomic methods were next employed to identify putative symbiosis factors: genes found in bacteria that restore microbiota-dependent traits to gnotobiotic flies, but absent from those that do not. Factors identified include riboflavin synthesis and stress resistance. We also used a phylogenomic approach to identify protein coding genes for which fly-isolate sequences were more similar to each other than to other sequences, reasoning that these genes may have a shared function unique to the fly environment. This method identified genes in Acetobacter species that cluster in two distinct genomic loci: one predicted to be involved in oxidative stress detoxification and another encoding an efflux pump. In summary, we leveraged genomic and in vivo functional comparisons to identify candidate traits that distinguish symbiotic bacteria. These candidates can serve as the basis for further work investigating the genetic requirements of bacteria for function and persistence in the Drosophila gut. PMID:25408687

  3. Overview of a Surface-Ripened Cheese Community Functioning by Meta-Omics Analyses

    PubMed Central

    Teissandier, Aurélie; Onésime, Djamila; Loux, Valentin; Monnet, Christophe; Irlinger, Françoise; Landaud, Sophie; Leclercq-Perlat, Marie-Noëlle; Bento, Pascal; Fraud, Sébastien; Gibrat, Jean-François; Aubert, Julie; Fer, Frédéric; Guédon, Eric; Pons, Nicolas; Kennedy, Sean; Beckerich, Jean-Marie; Swennen, Dominique; Bonnarme, Pascal

    2015-01-01

    Cheese ripening is a complex biochemical process driven by microbial communities composed of both eukaryotes and prokaryotes. Surface-ripened cheeses are widely consumed all over the world and are appreciated for their characteristic flavor. Microbial community composition has been studied for a long time on surface-ripened cheeses, but only limited knowledge has been acquired about its in situ metabolic activities. We applied metagenomic, metatranscriptomic and biochemical analyses to an experimental surface-ripened cheese composed of nine microbial species during four weeks of ripening. By combining all of the data, we were able to obtain an overview of the cheese maturation process and to better understand the metabolic activities of the different community members and their possible interactions. Furthermore, differential expression analysis was used to select a set of biomarker genes, providing a valuable tool that can be used to monitor the cheese-making process. PMID:25867897

  4. An Approximate Dissipation Function for Large Strain Rubber Thermo-Mechanical Analyses

    NASA Technical Reports Server (NTRS)

    Johnson, Arthur R.; Chen, Tzi-Kang

    2003-01-01

    Mechanically induced viscoelastic dissipation is difficult to compute. When the constitutive model is defined by history integrals, the formula for dissipation is a double convolution integral. Since double convolution integrals are difficult to approximate, coupled thermo-mechanical analyses of highly viscous rubber-like materials cannot be made with most commercial finite element software. In this study, we present a method to approximate the dissipation for history integral constitutive models that represent Maxwell-like materials without approximating the double convolution integral. The method requires that the total stress can be separated into elastic and viscous components, and that the relaxation form of the constitutive law is defined with a Prony series. Numerical data is provided to demonstrate the limitations of this approximate method for determining dissipation. Rubber cylinders with imbedded steel disks and with an imbedded steel ball are dynamically loaded, and the nonuniform heating within the cylinders is computed.

  5. The Generality of Interview-Informed Functional Analyses: Systematic Replications in School and Home

    ERIC Educational Resources Information Center

    Santiago, Joana L.; Hanley, Gregory P.; Moore, Keira; Jin, C. Sandy

    2016-01-01

    Behavioral interventions preceded by a functional analysis have been proven efficacious in treating severe problem behavior associated with autism. There is, however, a lack of research showing socially validated outcomes when assessment and treatment procedures are conducted by ecologically relevant individuals in typical settings. In this study,…

  6. Expression and in vitro functional analyses of recombinant Gam1 protein.

    PubMed

    Avila, Gustavo A; Ramirez, Daniel H; Hildenbrand, Zacariah L; Jacquez, Pedro; Chiocca, Susanna; Sun, Jianjun; Rosas-Acosta, German; Xiao, Chuan

    2015-01-01

    Gam1, an early gene product of an avian adenovirus, is essential for viral replication. Gam1 is the first viral protein found to globally inhibit cellular SUMOylation, a critical posttranslational modification that alters the function and cellular localization of proteins. The interaction details at the interface between Gam1 and its cellular targets remain unclear due to the lack of structural information. Although Gam1 has been previously characterized, the purity of the protein was not suitable for structural investigations. In the present study, the gene of Gam1 was cloned and expressed in various bacterial expression systems to obtain pure and soluble recombinant Gam1 protein for in vitro functional and structural studies. While Gam1 was insoluble in most expression systems tested, it became soluble when it was expressed as a fusion protein with trigger factor (TF), a ribosome associated bacterial chaperone, under the control of a cold shock promoter. Careful optimization indicates that both low temperature induction and the chaperone function of TF play critical roles in increasing Gam1 solubility. Soluble Gam1 was purified to homogeneity through sequential chromatography techniques. Monomeric Gam1 was obtained via size exclusion chromatography and analyzed by dynamic light scattering. The SUMOylation inhibitory function of the purified Gam1 was confirmed in an in vitro assay. These results have built the foundation for further structural investigations that will broaden our understanding of Gam1's roles in viral replication.

  7. Replicated landscape genetic and network analyses reveal wide variation in functional connectivity for American pikas.

    PubMed

    Castillo, Jessica A; Epps, Clinton W; Jeffress, Mackenzie R; Ray, Chris; Rodhouse, Thomas J; Schwalm, Donelle

    2016-09-01

    Landscape connectivity is essential for maintaining viable populations, particularly for species restricted to fragmented habitats or naturally arrayed in metapopulations and facing rapid climate change. The importance of assessing both structural connectivity (physical distribution of favorable habitat patches) and functional connectivity (how species move among habitat patches) for managing such species is well understood. However, the degree to which functional connectivity for a species varies among landscapes, and the resulting implications for conservation, have rarely been assessed. We used a landscape genetics approach to evaluate resistance to gene flow and, thus, to determine how landscape and climate-related variables influence gene flow for American pikas (Ochotona princeps) in eight federally managed sites in the western United States. We used empirically derived, individual-based landscape resistance models in conjunction with predictive occupancy models to generate patch-based network models describing functional landscape connectivity. Metareplication across landscapes enabled identification of limiting factors for dispersal that would not otherwise have been apparent. Despite the cool microclimates characteristic of pika habitat, south-facing aspects consistently represented higher resistance to movement, supporting the previous hypothesis that exposure to relatively high temperatures may limit dispersal in American pikas. We found that other barriers to dispersal included areas with a high degree of topographic relief, such as cliffs and ravines, as well as streams and distances greater than 1-4 km depending on the site. Using the empirically derived network models of habitat patch connectivity, we identified habitat patches that were likely disproportionately important for maintaining functional connectivity, areas in which habitat appeared fragmented, and locations that could be targeted for management actions to improve functional connectivity

  8. Structure-function analyses of microsomal triglyceride transfer protein missense mutations in abetalipoproteinemia and hypobetalipoproteinemia subjects.

    PubMed

    Walsh, Meghan T; Di Leo, Enza; Okur, Ilyas; Tarugi, Patrizia; Hussain, M Mahmood

    2016-11-01

    We describe two new hypolipidemic patients with very low plasma triglyceride and apolipoprotein B (apoB) levels with plasma lipid profiles similar to abetalipoproteinemia (ABL) patients. In these patients, we identified two previously uncharacterized missense mutations in the microsomal triglyceride transfer protein (MTP) gene, R46G and D361Y, and studied their functional effects. We also characterized three missense mutations (H297Q, D384A, and G661A) reported earlier in a familial hypobetalipoproteinemia patient. R46G had no effect on MTP expression or function and supported apoB secretion. H297Q, D384A, and G661A mutants also supported apoB secretion similarly to WT MTP. Contrary to these four missense mutations, D361Y was unable to support apoB secretion. Functional analysis revealed that this mutant was unable to bind protein disulfide isomerase (PDI) or transfer lipids. The negative charge at residue 361 was critical for MTP function as D361E was able to support apoB secretion and transfer lipids. D361Y most likely disrupts the tightly packed middle α-helical region of MTP, mitigates PDI binding, abolishes lipid transfer activity, and causes ABL. On the other hand, the hypolipidemia in the other two patients was not due to MTP dysfunction. Thus, in this study of five missense mutations spread throughout MTP's three structural domains found in three hypolipidemic patients, we found that four of the mutations did not affect MTP function. Thus, novel mutations that cause severe hypolipidemia probably exist in other genes in these patients, and their recognition may identify novel proteins involved in the synthesis and/or catabolism of plasma lipoproteins.

  9. Comparative Analyses of Aryl Hydrocarbon Receptor Structure, Function, and Evolution in Marine Mammals

    DTIC Science & Technology

    2007-02-01

    established that bony fishes possess mechanisms of detoxication (Andersson and Forlin 1992; Hahn et al. 1998) that could effectively reduce their PAH...differences that can be critically important in predicting the effects of drugs or toxicants in humans. It is vital to understand such differences in order...Species-specific differences in AHR structure can affect an organism’s susceptibility to the effects of DLC. The structures and functions of several

  10. A cell-permeable tool for analysing APP intracellular domain function and manipulation of PIKfyve activity

    PubMed Central

    Guscott, Benjamin; Balklava, Zita; Safrany, Stephen T.; Wassmer, Thomas

    2016-01-01

    The mechanisms for regulating PIKfyve complex activity are currently emerging. The PIKfyve complex, consisting of the phosphoinositide kinase PIKfyve (also known as FAB1), VAC14 and FIG4, is required for the production of phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2]. PIKfyve function is required for homoeostasis of the endo/lysosomal system and is crucially implicated in neuronal function and integrity, as loss of function mutations in the PIKfyve complex lead to neurodegeneration in mouse models and human patients. Our recent work has shown that the intracellular domain of the amyloid precursor protein (APP), a molecule central to the aetiology of Alzheimer's disease binds to VAC14 and enhances PIKfyve function. In the present study, we utilize this recent advance to create an easy-to-use tool for increasing PIKfyve activity in cells. We fused APP intracellular domain (AICD) to the HIV TAT domain, a cell-permeable peptide allowing proteins to penetrate cells. The resultant TAT–AICD fusion protein is cell permeable and triggers an increase in PI(3,5)P2. Using the PI(3,5)P2 specific GFP-ML1Nx2 probe, we show that cell-permeable AICD alters PI(3,5)P2 dynamics. TAT–AICD also provides partial protection from pharmacological inhibition of PIKfyve. All three lines of evidence show that the AICD activates the PIKfyve complex in cells, a finding that is important for our understanding of the mechanism of neurodegeneration in Alzheimer's disease. PMID:26934981

  11. Functional analyses of carnivorous plant-specific amino acid residues in S-like ribonucleases.

    PubMed

    Arai, Naoki; Nishimura, Emi; Kikuchi, Yo; Ohyama, Takashi

    2015-09-11

    Unlike plants with no carnivory, carnivorous plants seem to use S-like ribonucleases (RNases) as an enzyme for carnivory. Carnivorous plant-specific conserved amino acid residues are present at four positions around the conserved active site (CAS). The roles of these conserved amino acid residues in the enzymatic function were explored in the current study by preparing five recombinant variants of DA-I, the S-like RNase of Drosera adelae. The kcat and kcat/Km values of the enzymes revealed that among the four variants with a single mutation, the serine to glycine mutation at position 111 most negatively influenced the enzymatic activity. The change in the bulkiness of the amino acid residue side-chain seemed to be the major cause of the above effect. Modeling of the three dimensional (3D) structures strongly suggested that the S to G mutation at 111 greatly altered the overall enzyme conformation. The conserved four amino acid residues are likely to function in keeping the two histidine residues, which are essential for the cleavage of RNA strands, and the CAS in the most functional enzymatic conformation.

  12. Performance of the platelet function analyser PFA-100 in testing abnormalities of primary haemostasis.

    PubMed

    Harrison, P; Robinson, M S; Mackie, I J; Joseph, J; McDonald, S J; Liesner, R; Savidge, G F; Pasi, J; Machin, S J

    1999-01-01

    The PFA-100 device is a new instrument for the in-vitro testing of platelet function. Primary haemostasis is stimulated by recording the closure time taken for platelets to seal a 150 microm aperture in the centre of a membrane coated with collagen and either epinephrine or ADP. Patients with type 3 von Willebrand's disease (n = 4) all had infinitely prolonged closure times (> 200 s) with both types of cartridge. A patient with afibrinogenemia exhibited only slightly prolonged closure times of 111 and 166 s for the ADP and epinephrine membranes, respectively. Patients with Glanzmann's thrombasthenia (n = 6) and Bernard Soulier syndrome (n = 2) had grossly prolonged closure times (> 200 s) with both types of cartridges. These results confirmed that the PFA-100 system was highly dependent on normal von Willebrand factor, glycoprotein Ib and glycoprotein IIb/IIIa levels but not on plasma fibrinogen. Patients with storage pool disease (n = 6) and Hermansky Pudlak syndrome (n = 7) had prolonged closure times with the epinephrine cartridge. There was no evidence of enhanced platelet function in patients with antiphospholipid syndrome, in sickle-cell disease or thalassemia. However, ingestion of aspirin resulted in a near consistent and significant prolongation of the closure time for the epinephrine cartridge but not for the ADP cartridge in both normal subjects and patients. The test offers a reliable, reproducible, rapid and simple means of assessing high-shear platelet function in vitro.

  13. Genomic and functional analyses of Mycobacterium tuberculosis strains implicate ald in D-cycloserine resistance

    PubMed Central

    Desjardins, Christopher A.; Cohen, Keira A.; Munsamy, Vanisha; Abeel, Thomas; Maharaj, Kashmeel; Walker, Bruce J.; Shea, Terrance P.; Almeida, Deepak V.; Manson, Abigail L.; Salazar, Alex; Padayatchi, Nesri; O’Donnell, Max R.; Mlisana, Koleka P.; Wortman, Jennifer; Birren, Bruce W.; Grosset, Jacques; Earl, Ashlee M.; Pym, Alexander S.

    2016-01-01

    A more complete understanding of the genetic basis of drug resistance in Mycobacterium tuberculosis is critical for prompt diagnosis and optimal treatment, particularly for toxic second-line drugs like D-cycloserine. Here, we used whole-genome sequences from 498 strains of M. tuberculosis to identify novel resistance-conferring genotypes. By combining association and correlated evolution tests with strategies for amplifying signal from rare variants, we found that loss-of-function mutations in ald (Rv2780), encoding L-alanine dehydrogenase, were associated with unexplained drug resistance. Convergent evolution of this loss-of-function was observed exclusively among multidrug-resistant strains. Drug susceptibility testing established that ald loss-of-function conferred resistance to D-cycloserine, and susceptibility to the drug was partially restored by complementation of ald. Clinical strains with mutations in ald and alr exhibited increased resistance to D-cycloserine when cultured in vitro. Incorporation of D-cycloserine resistance in novel molecular diagnostics could allow for targeted utilization of this toxic drug among patients with susceptible infections. PMID:27064254

  14. The extended fronto-striatal model of obsessive compulsive disorder: convergence from event-related potentials, neuropsychology and neuroimaging

    PubMed Central

    Melloni, Margherita; Urbistondo, Claudia; Sedeño, Lucas; Gelormini, Carlos; Kichic, Rafael; Ibanez, Agustin

    2012-01-01

    In this work, we explored convergent evidence supporting the fronto-striatal model of obsessive-compulsive disorder (FSMOCD) and the contribution of event-related potential (ERP) studies to this model. First, we considered minor modifications to the FSMOCD model based on neuroimaging and neuropsychological data. We noted the brain areas most affected in this disorder -anterior cingulate cortex (ACC), basal ganglia (BG), and orbito-frontal cortex (OFC) and their related cognitive functions, such as monitoring and inhibition. Then, we assessed the ERPs that are directly related to the FSMOCD, including the error-related negativity (ERN), N200, and P600. Several OCD studies present enhanced ERN and N2 responses during conflict tasks as well as an enhanced P600 during working memory (WM) tasks. Evidence from ERP studies (especially regarding ERN and N200 amplitude enhancement), neuroimaging and neuropsychological findings suggests abnormal activity in the OFC, ACC, and BG in OCD patients. Moreover, additional findings from these analyses suggest dorsolateral prefrontal and parietal cortex involvement, which might be related to executive function (EF) deficits. Thus, these convergent results suggest the existence of a self-monitoring imbalance involving inhibitory deficits and executive dysfunctions. OCD patients present an impaired ability to monitor, control, and inhibit intrusive thoughts, urges, feelings, and behaviors. In the current model, this imbalance is triggered by an excitatory role of the BG (associated with cognitive or motor actions without volitional control) and inhibitory activity of the OFC as well as excessive monitoring of the ACC to block excitatory impulses. This imbalance would interact with the reduced activation of the parietal-DLPC network, leading to executive dysfunction. ERP research may provide further insight regarding the temporal dynamics of action monitoring and executive functioning in OCD. PMID:23015786

  15. Survival features of EBV-stabilized cells from centenarians: morpho-functional and transcriptomic analyses.

    PubMed

    Matarrese, Paola; Tinari, Antonella; Ascione, Barbara; Gambardella, Lucrezia; Remondini, Daniel; Salvioli, Stefano; Tenedini, Elena; Tagliafico, Enrico; Franceschi, Claudio; Malorni, Walter

    2012-12-01

    In the present work, we analyzed the survival features of six different Epstein-Barr virus (EBV)-stabilized lymphoid cell lines obtained from adult subjects and from subjects of more than 95 years. For the first, we found that lymphoid B cells from centenarians were more resistant to apoptosis induction and displayed a more developed lysosomal compartment, the most critical component of phagic machinery, in comparison with lymphoid B cells from adult subjects. In addition, cells from centenarians were capable of engulfing and digesting other cells, i.e., their siblings (even entire cells), whereas lymphoid cells from "control samples", i.e., from adults, did not. This behavior was improved by nutrient deprivation but, strikingly, it was unaffected by the autophagy-modulating drug, rapamycin, an autophagy inducer, and 3-methyladenine, an autophagy inhibitor. Transcriptomic analyses indicated that: (1) aspartyl proteases, (2) cell surface molecules such as integrins and cadherins, and (3) some components of cytoskeletal network could contribute to establish this survival phenotype. Also, Kyoto Encyclopedia of Genes and Genomes pathways such as Wnt signaling pathway, an essential contributor to cell migration and actin cytoskeleton remodeling, appeared as prominent. Although we cannot rule out the possibility that EBV-immortalization could play a role, since we observed this phagic behavior in cells from centenarians but not in those from adults, we hypothesize that it may represent an important survival determinant in cells from centenarians.

  16. Characterization of branch complexity by fractal analyses and detect plant functional adaptations

    USGS Publications Warehouse

    Alados, C.L.; Escos, J.; Emlen, J.M.; Freeman, D.C.

    1999-01-01

    The comparison between complexity in the sense of space occupancy (box-counting fractal dimension Dc and information dimension DI ) and heterogeneity in the sense of space distribution (average evenness index and evenness variation coefficient JCV) were investigated in mathematical fractal objects and natural branch ¯ J structures. In general, increased fractal dimension was paired with low heterogeneity. Comparisons between branch architecture in Anthyllis cytisoides under different slope exposure and grazing impact revealed that branches were more complex and more homogeneously distributed for plants on northern exposures than southern, while grazing had no impact during a wet year. Developmental instability was also investigated by the statistical noise of the allometric relation between internode length and node order. In conclusion, our study demonstrated that fractal dimension of branch structure can be used to analyze the structural organization of plants, especially if we consider not only fractal dimension but also shoot distribution within the canopy (lacunarity). These indexes together with developmental instability analyses are good indicators of growth responses to the environment.

  17. Functional and fluorescence analyses of tryptophan residues in H+-pyrophosphatase of Clostridium tetani.

    PubMed

    Chen, Yen-Wei; Lee, Ching-Hung; Huang, Yun-Tzu; Pan, Yih-Jiuan; Lin, Shih-Ming; Lo, Yueh-Yu; Lee, Chien-Hsien; Huang, Lin-Kun; Huang, Yu-Fen; Hsu, Yu-Di; Pan, Rong-Long

    2014-04-01

    Homodimeric proton-translocating pyrophosphatase (H+-PPase; EC 3.6.1.1) maintains the cytoplasmic pH homeostasis of many bacteria and higher plants by coupling pyrophosphate (PPi) hydrolysis and proton translocation. H+-PPase accommodates several essential motifs involved in the catalytic mechanism, including the PPi binding motif and Acidic I and II motifs. In this study, 3 intrinsic tryptophan residues, Trp-75, Trp-365, and Trp-602, in H+-PPase from Clostridium tetani were used as internal probes to monitor the local conformational state of the periplasm domain, transmembrane region, and cytoplasmic domain, respectively. Upon binding of the substrate analog Mg-imidodiphosphate (Mg-IDP), local structural changes prevented the modification of tryptophan residues by N-bromosuccinimide (NBS), especially at Trp-602. Following Mg-Pi binding, Trp-75 and Trp-365, but not Trp-602, were slightly protected from structural modifications by NBS. These results reveal the conformation of H+-PPase is distinct in the presence of different ligands. Moreover, analyses of the Stern-Volmer relationship and steady-state fluorescence anisotropy also indicate that the local structure around Trp-602 is more exposed to solvent and varied under different environments. In addition, Trp-602 was identified to be a crucial residue in the H+-PPase that may potentially be involved in stabilizing the structure of the catalytic region by site-directed mutagenesis analysis.

  18. Functional and expression analyses of transcripts based on full-length cDNAs of Sorghum bicolor.

    PubMed

    Shimada, Setsuko; Makita, Yuko; Kuriyama-Kondou, Tomoko; Kawashima, Mika; Mochizuki, Yoshiki; Hirakawa, Hideki; Sato, Shusei; Toyoda, Tetsuro; Matsui, Minami

    2015-12-01

    Sorghum bicolor is one of the most important crops for food and bioethanol production. Its small diploid genome and resistance to environmental stress make sorghum an attractive model for studying the functional genomics of the Saccharinae and other C4 grasses. We analyzed the domain-based functional annotation of the cDNAs using the gene ontology (GO) categories for molecular function to characterize all the genes cloned in the full-length cDNA library of sorghum. The sorghum cDNA library successfully captured a wide range of cDNA-encoded proteins with various functions. To characterize the protein function of newly identified cDNAs, a search of their deduced domains and comparative analyses in the Oryza sativa and Zea mays genomes were carried out. Furthermore, genes on the sense strand corresponding to antisense transcripts were classified based on the GO of molecular function. To add more information about these genes, we have analyzed the expression profiles using RNA-Seq of three tissues (spikelet, seed and stem) during the starch-filling phase. We performed functional analysis of tissue-specific genes and expression analysis of genes of starch biosynthesis enzymes. This functional analysis of sorghum full-length cDNAs and the transcriptome information will facilitate further analysis of the Saccharinae and grass families.

  19. Functional and expression analyses of transcripts based on full-length cDNAs of Sorghum bicolor

    PubMed Central

    Shimada, Setsuko; Makita, Yuko; Kuriyama-Kondou, Tomoko; Kawashima, Mika; Mochizuki, Yoshiki; Hirakawa, Hideki; Sato, Shusei; Toyoda, Tetsuro; Matsui, Minami

    2015-01-01

    Sorghum bicolor is one of the most important crops for food and bioethanol production. Its small diploid genome and resistance to environmental stress make sorghum an attractive model for studying the functional genomics of the Saccharinae and other C4 grasses. We analyzed the domain-based functional annotation of the cDNAs using the gene ontology (GO) categories for molecular function to characterize all the genes cloned in the full-length cDNA library of sorghum. The sorghum cDNA library successfully captured a wide range of cDNA-encoded proteins with various functions. To characterize the protein function of newly identified cDNAs, a search of their deduced domains and comparative analyses in the Oryza sativa and Zea mays genomes were carried out. Furthermore, genes on the sense strand corresponding to antisense transcripts were classified based on the GO of molecular function. To add more information about these genes, we have analyzed the expression profiles using RNA-Seq of three tissues (spikelet, seed and stem) during the starch-filling phase. We performed functional analysis of tissue-specific genes and expression analysis of genes of starch biosynthesis enzymes. This functional analysis of sorghum full-length cDNAs and the transcriptome information will facilitate further analysis of the Saccharinae and grass families. PMID:26546227

  20. Practical management of heterogeneous neuroimaging metadata by global neuroimaging data repositories.

    PubMed

    Neu, Scott C; Crawford, Karen L; Toga, Arthur W

    2012-01-01

    Rapidly evolving neuroimaging techniques are producing unprecedented quantities of digital data at the same time that many research studies are evolving into global, multi-disciplinary collaborations between geographically distributed scientists. While networked computers have made it almost trivial to transmit data across long distances, collecting and analyzing this data requires extensive metadata if the data is to be maximally shared. Though it is typically straightforward to encode text and numerical values into files and send content between different locations, it is often difficult to attach context and implicit assumptions to the content. As the number of and geographic separation between data contributors grows to national and global scales, the heterogeneity of the collected metadata increases and conformance to a single standardization becomes implausible. Neuroimaging data repositories must then not only accumulate data but must also consolidate disparate metadata into an integrated view. In this article, using specific examples from our experiences, we demonstrate how standardization alone cannot achieve full integration of neuroimaging data from multiple heterogeneous sources and why a fundamental change in the architecture of neuroimaging data repositories is needed instead.

  1. The Extensible Neuroimaging Archive Toolkit: an informatics platform for managing, exploring, and sharing neuroimaging data.

    PubMed

    Marcus, Daniel S; Olsen, Timothy R; Ramaratnam, Mohana; Buckner, Randy L

    2007-01-01

    The Extensible Neuroimaging Archive Toolkit (XNAT) is a software platform designed to facilitate common management and productivity tasks for neuroimaging and associated data. In particular, XNAT enables qualitycontrol procedures and provides secure access to and storage of data. XNAT follows a threetiered architecture that includes a data archive, user interface, and middleware engine. Data can be entered into the archive as XML or through data entry forms. Newly added data are stored in a virtual quarantine until an authorized user has validated it. XNAT subsequently maintains a history profile to track all changes made to the managed data. User access to the archive is provided by a secure web application. The web application provides a number of quality control and productivity features, including data entry forms, data-type-specific searches, searches that combine across data types, detailed reports, and listings of experimental data, upload/download tools, access to standard laboratory workflows, and administration and security tools. XNAT also includes an online image viewer that supports a number of common neuroimaging formats, including DICOM and Analyze. The viewer can be extended to support additional formats and to generate custom displays. By managing data with XNAT, laboratories are prepared to better maintain the long-term integrity of their data, to explore emergent relations across data types, and to share their data with the broader neuroimaging community.

  2. Functional analyses of the Physcomitrella patens phytochromes in regulating chloroplast avoidance movement.

    PubMed

    Uenaka, Hidetoshi; Kadota, Akeo

    2007-09-01

    Red light-induced chloroplast movement in Physcomitrella patens (Pp) is mediated by dichroic phytochrome in the cytoplasm. To analyze the molecular function of the photoreceptor in the cytoplasm, we developed a protoplast system in which chloroplast photomovement was exclusively dependent on the expression of phytochrome cDNA constructs introduced by polyethylene glycol (PEG) transformation. YFP was fused to the phytochrome constructs and their expression was detected by fluorescence. The chloroplast avoidance response was induced in the protoplasts expressing a YFP fusion of PHY1-PHY3, but not of PHY4 or YFP alone. Phy::yfp fluorescence was detected in the cytoplasm. No change in the location of phy1::yfp or phy2::yfp was revealed before and after photomovement. When phy1::yfp and phy2::yfp were targeted to the nucleus by fusing a nuclear localization signal to the constructs, red light avoidance was not induced. To determine the domains of PHY2 essential for avoidance response, various partially-deleted PHY2::YFP constructs were tested. The N-terminal extension domain (NTE) was found to be necessary but the C-terminal histidine kinase-related domain (HKRD) was dispensable. An avoidance response was not induced under expression of phytochrome N-terminal half domain [deleting both the PAS (Per, Arnt, Sim)-related domain (PRD) and HKRD]. GUS fusion of this N-terminal half domain, reported to be fully functional in Arabidopsis for several phyA- and phyB-regulated responses was not effective in chloroplast avoidance movement. Domain requirement and GUS fusion effect were also confirmed in PHY1. These results indicate that Pp phy1-Pp phy3 in the cytoplasm mediate chloroplast avoidance movement, and that NTE and PRD, but not HKRD, are required for their function.

  3. Functional connectivity analyses in imaging genetics: considerations on methods and data interpretation.

    PubMed

    Bedenbender, Johannes; Paulus, Frieder M; Krach, Sören; Pyka, Martin; Sommer, Jens; Krug, Axel; Witt, Stephanie H; Rietschel, Marcella; Laneri, Davide; Kircher, Tilo; Jansen, Andreas

    2011-01-01

    Functional magnetic resonance imaging (fMRI) can be combined with genotype assessment to identify brain systems that mediate genetic vulnerability to mental disorders ("imaging genetics"). A data analysis approach that is widely applied is "functional connectivity". In this approach, the temporal correlation between the fMRI signal from a pre-defined brain region (the so-called "seed point") and other brain voxels is determined. In this technical note, we show how the choice of freely selectable data analysis parameters strongly influences the assessment of the genetic modulation of connectivity features. In our data analysis we exemplarily focus on three methodological parameters: (i) seed voxel selection, (ii) noise reduction algorithms, and (iii) use of additional second level covariates. Our results show that even small variations in the implementation of a functional connectivity analysis can have an impact on the connectivity pattern that is as strong as the potential modulation by genetic allele variants. Some effects of genetic variation can only be found for one specific implementation of the connectivity analysis. A reoccurring difficulty in the field of psychiatric genetics is the non-replication of initially promising findings, partly caused by the small effects of single genes. The replication of imaging genetic results is therefore crucial for the long-term assessment of genetic effects on neural connectivity parameters. For a meaningful comparison of imaging genetics studies however, it is therefore necessary to provide more details on specific methodological parameters (e.g., seed voxel distribution) and to give information how robust effects are across the choice of methodological parameters.

  4. Functional and comparative genomics analyses of pmp22 in medaka fish

    PubMed Central

    Itou, Junji; Suyama, Mikita; Imamura, Yukio; Deguchi, Tomonori; Fujimori, Kazuhiro; Yuba, Shunsuke; Kawarabayasi, Yutaka; Kawasaki, Takashi

    2009-01-01

    Background Pmp22, a member of the junction protein family Claudin/EMP/PMP22, plays an important role in myelin formation. Increase of pmp22 transcription causes peripheral neuropathy, Charcot-Marie-Tooth disease type1A (CMT1A). The pathophysiological phenotype of CMT1A is aberrant axonal myelination which induces a reduction in nerve conduction velocity (NCV). Several CMT1A model rodents have been established by overexpressing pmp22. Thus, it is thought that pmp22 expression must be tightly regulated for correct myelin formation in mammals. Interestingly, the myelin sheath is also present in other jawed vertebrates. The purpose of this study is to analyze the evolutionary conservation of the association between pmp22 transcription level and vertebrate myelin formation, and to find the conserved non-coding sequences for pmp22 regulation by comparative genomics analyses between jawed fishes and mammals. Results A transgenic pmp22 over-expression medaka fish line was established. The transgenic fish had approximately one fifth the peripheral NCV values of controls, and aberrant myelination of transgenic fish in the peripheral nerve system (PNS) was observed. We successfully confirmed that medaka fish pmp22 has the same exon-intron structure as mammals, and identified some known conserved regulatory motifs. Furthermore, we found novel conserved sequences in the first intron and 3'UTR. Conclusion Medaka fish undergo abnormalities in the PNS when pmp22 transcription increases. This result indicates that an adequate pmp22 transcription level is necessary for correct myelination of jawed vertebrates. Comparison of pmp22 orthologs between distantly related species identifies evolutionary conserved sequences that contribute to precise regulation of pmp22 expression. PMID:19534778

  5. Structural, functional, and genetic analyses of the actinobacterial transcription factor RbpA.

    PubMed

    Hubin, Elizabeth A; Tabib-Salazar, Aline; Humphrey, Laurence J; Flack, Joshua E; Olinares, Paul Dominic B; Darst, Seth A; Campbell, Elizabeth A; Paget, Mark S

    2015-06-09

    Gene expression is highly regulated at the step of transcription initiation, and transcription activators play a critical role in this process. RbpA, an actinobacterial transcription activator that is essential in Mycobacterium tuberculosis (Mtb), binds selectively to group 1 and certain group 2 σ-factors. To delineate the molecular mechanism of RbpA, we show that the Mtb RbpA σ-interacting domain (SID) and basic linker are sufficient for transcription activation. We also present the crystal structure of the Mtb RbpA-SID in complex with domain 2 of the housekeeping σ-factor, σ(A). The structure explains the basis of σ-selectivity by RbpA, showing that RbpA interacts with conserved regions of σ(A) as well as the nonconserved region (NCR), which is present only in housekeeping σ-factors. Thus, the structure is the first, to our knowledge, to show a protein interacting with the NCR of a σ-factor. We confirm the basis of selectivity and the observed interactions using mutagenesis and functional studies. In addition, the structure allows for a model of the RbpA-SID in the context of a transcription initiation complex. Unexpectedly, the structural modeling suggests that RbpA contacts the promoter DNA, and we present in vivo and in vitro studies supporting this finding. Our combined data lead to a better understanding of the mechanism of RbpA function as a transcription activator.

  6. Functional proteomic analyses of Bothrops atrox venom reveals phenotypes associated with habitat variation in the Amazon.

    PubMed

    Sousa, Leijiane F; Portes-Junior, José A; Nicolau, Carolina A; Bernardoni, Juliana L; Nishiyama-Jr, Milton Y; Amazonas, Diana R; Freitas-de-Sousa, Luciana A; Mourão, Rosa Hv; Chalkidis, Hipócrates M; Valente, Richard H; Moura-da-Silva, Ana M

    2017-03-06

    Venom variability is commonly reported for venomous snakes including Bothrops atrox. Here, we compared the composition of venoms from B. atrox snakes collected at Amazonian conserved habitats (terra-firme upland forest and várzea) and human modified areas (pasture and degraded areas). Venom samples were submitted to shotgun proteomic analysis as a whole or compared after fractionation by reversed-phase chromatography. Whole venom proteomes revealed a similar composition among the venoms with predominance of SVMPs, CTLs, and SVSPs and intermediate amounts of PLA2s and LAAOs. However, when distribution of particular isoforms was analyzed by either method, the venom from várzea snakes showed a decrease in hemorrhagic SVMPs and an increase in SVSPs, and procoagulant SVMPs and PLA2s. These differences were validated by experimental approaches including both enzymatic and in vivo assays, and indicated restrictions in respect to antivenom efficacy to variable components. Thus, proteomic analysis at the isoform level combined to in silico prediction of functional properties may indicate venom biological activity. These results also suggest that the prevalence of functionally distinct isoforms contributes to the variability of the venoms and could reflect the adaptation of B. atrox to distinct prey communities in different Amazon habitats.

  7. Genomic distribution and functional analyses of potential G-quadruplex-forming sequences in Saccharomyces cerevisiae

    PubMed Central

    Hershman, Steve G.; Chen, Qijun; Lee, Julia Y.; Kozak, Marina L.; Yue, Peng; Wang, Li-San; Johnson, F. Brad

    2008-01-01

    Although well studied in vitro, the in vivo functions of G-quadruplexes (G4-DNA and G4-RNA) are only beginning to be defined. Recent studies have demonstrated enrichment for sequences with intramolecular G-quadruplex forming potential (QFP) in transcriptional promoters of humans, chickens and bacteria. Here we survey the yeast genome for QFP sequences and similarly find strong enrichment for these sequences in upstream promoter regions, as well as weaker but significant enrichment in open reading frames (ORFs). Further, four findings are consistent with roles for QFP sequences in transcriptional regulation. First, QFP is correlated with upstream promoter regions with low histone occupancy. Second, treatment of cells with N-methyl mesoporphyrin IX (NMM), which binds G-quadruplexes selectively in vitro, causes significant upregulation of loci with QFP-possessing promoters or ORFs. NMM also causes downregulation of loci connected with the function of the ribosomal DNA (rDNA), which itself has high QFP. Third, ORFs with QFP are selectively downregulated in sgs1 mutants that lack the G4-DNA-unwinding helicase Sgs1p. Fourth, a screen for yeast mutants that enhance or suppress growth inhibition by NMM revealed enrichment for chromatin and transcriptional regulators, as well as telomere maintenance factors. These findings raise the possibility that QFP sequences form bona fide G-quadruplexes in vivo and thus regulate transcription. PMID:17999996

  8. Analyses of Old “Prokaryotic” Proteins Indicate Functional Diversification in Arabidopsis and Oryza sativa

    PubMed Central

    Singh, Anupama; Jethva, Minesh; Singla-Pareek, Sneh L.; Pareek, Ashwani; Kushwaha, Hemant R.

    2016-01-01

    During evolution, various processes such as duplication, divergence, recombination, and many other events leads to the evolution of new genes with novel functions. These evolutionary events, thus significantly impact the evolution of cellular, physiological, morphological, and other phenotypic trait of organisms. While evolving, eukaryotes have acquired large number of genes from the earlier prokaryotes. This work is focused upon identification of old “prokaryotic” proteins in Arabidopsis and Oryza sativa genome, further highlighting their possible role(s) in the two genomes. Our results suggest that with respect to their genome size, the fraction of old “prokaryotic” proteins is higher in Arabidopsis than in Oryza sativa. The large fractions of such proteins encoding genes were found to be localized in various endo-symbiotic organelles. The domain architecture of the old “prokaryotic” proteins revealed similar distribution in both Arabidopsis and Oryza sativa genomes showing their conserved evolution. In Oryza sativa, the old “prokaryotic” proteins were more involved in developmental processes, might be due to constant man-made selection pressure for better agronomic traits/productivity. While in Arabidopsis, these proteins were involved in metabolic functions. Overall, the analysis indicates the distinct pattern of evolution of old “prokaryotic” proteins in Arabidopsis and Oryza sativa. PMID:27014324

  9. Are pinnipeds functionally different from fissiped carnivores? The importance of phylogenetic comparative analyses.

    PubMed

    Bininda-Emonds, O R; Gittleman, J L

    2000-06-01

    It is widely assumed that adaptations to an aquatic lifestyle are so profound as to produce only obvious differences between pinnipeds and the remaining, largely terrestrial carnivore species ("fissipeds"). Thus, comparative studies of the order Carnivora routinely examine these groups independently. This approach is invalid for two reasons. First, fissipeds are a paraphyletic assemblage, which raises the general issue of when it is appropriate to ignore monophyly as a criterion for inclusion in comparative studies. Second, the claim that most functional characters (beyond a few undoubted characteristic features) are different in pinnipeds and fissipeds has never been quantitatively examined, nor with phylogenetic comparative methods. We test for possible differences between these two groups in relation to 20 morphological, life-history, physiological, and ecological variables. Comparisons employed the method of independent contrasts based on a complete and dated species-level phylogeny of the extant Carnivora. Pinnipeds differ from fissipeds only through evolutionary grade shifts in a limited number of life-history traits: litter weight (vs. gestation length), birth weight, and age of eyes opening (both vs. size). Otherwise, pinnipeds display the same rate of evolution as phylogenetically equivalent fissiped taxa for all variables. Overall functional differences between pinnipeds and fissipeds appear to have been overstated and may be no greater than those among major fissiped groups. Recognition of this fact should lead to a more complete understanding of carnivore biology as a whole through more unified comparative tests. Comparative studies that do not include monophyletic groups for phylogenetically based comparative tests should be reconsidered.

  10. [Side effect analyses in consideration of renal functions for capecitabine-administered patients].

    PubMed

    Iwai, Mina; Kimura, Michio; Yoshimura, Tomoaki; Yasuda, Tadashi

    2012-05-01

    There is a high frequency of serious side effects overseas in cases with a reduced creatinine clearance, for whom a 75% reduction in dose administration is recommended. The insidence of hematological toxicity was investigated in 89 cases[L group: Ccr<5 0mL/min(6 cases), M group: 50mL/min≤Ccr<80mL/min(34 cases), and H group: 80mL/min≤Ccr(49 cases)]who took capecitabine alone. The frequency of side effects was significantly high in group L[L: 6 cases(100%), M: 30 cases(88. 2%), and H: 30 cases(61. 2%)]. The frequency of grade 2 or more was higher in cases with a reduced renal function[L: 5 cases(83. 3%),M: 17 cases(50. 0%), and H: 18 cases(36. 7%)]. A significantly high decrease in hemoglobin was seen in group L[all grades; L: 5 cases(83. 3%),M: 20 cases(58. 8%), and H: 12 cases(24. 5%), and a grade 2 or more; L: 5 cases (83. 3%), M: 7 cases(20. 6%), and H: 5 cases (10. 2%)]. Moreover, there was little improvement when a decrease in hemoglobin occurred in grade 3 cases. Our findings suggest that it is necessary to manage drug dosage for Japanese patients while considering their renal function, and to actively monitor for any side effects.

  11. Integrative analyses of transcriptome sequencing identify novel functional lncRNAs in esophageal squamous cell carcinoma

    PubMed Central

    Li, C-Q; Huang, G-W; Wu, Z-Y; Xu, Y-J; Li, X-C; Xue, Y-J; Zhu, Y; Zhao, J-M; Li, M; Zhang, J; Wu, J-Y; Lei, F; Wang, Q-Y; Li, S; Zheng, C-P; Ai, B; Tang, Z-D; Feng, C-C; Liao, L-D; Wang, S-H; Shen, J-H; Liu, Y-J; Bai, X-F; He, J-Z; Cao, H-H; Wu, B-L; Wang, M-R; Lin, D-C; Koeffler, H P; Wang, L-D; Li, X; Li, E-M; Xu, L-Y

    2017-01-01

    Long non-coding RNAs (lncRNAs) have a critical role in cancer initiation and progression, and thus may mediate oncogenic or tumor suppressing effects, as well as be a new class of cancer therapeutic targets. We performed high-throughput sequencing of RNA (RNA-seq) to investigate the expression level of lncRNAs and protein-coding genes in 30 esophageal samples, comprised of 15 esophageal squamous cell carcinoma (ESCC) samples and their 15 paired non-tumor tissues. We further developed an integrative bioinformatics method, denoted URW-LPE, to identify key functional lncRNAs that regulate expression of downstream protein-coding genes in ESCC. A number of known onco-lncRNA and many putative novel ones were effectively identified by URW-LPE. Importantly, we identified lncRNA625 as a novel regulator of ESCC cell proliferation, invasion and migration. ESCC patients with high lncRNA625 expression had significantly shorter survival time than those with low expression. LncRNA625 also showed specific prognostic value for patients with metastatic ESCC. Finally, we identified E1A-binding protein p300 (EP300) as a downstream executor of lncRNA625-induced transcriptional responses. These findings establish a catalog of novel cancer-associated functional lncRNAs, which will promote our understanding of lncRNA-mediated regulation in this malignancy. PMID:28194033

  12. Tetrahydrolipstatin Inhibition, Functional Analyses, and Three-dimensional Structure of a Lipase Essential for Mycobacterial Viability

    SciTech Connect

    Crellin, Paul K.; Vivian, Julian P.; Scoble, Judith; Chow, Frances M.; West, Nicholas P.; Brammananth, Rajini; Proellocks, Nicholas I.; Shahine, Adam; Le Nours, Jerome; Wilce, Matthew C.J.; Britton, Warwick J.; Coppel, Ross L.; Rossjohn, Jamie; Beddoe, Travis

    2010-09-17

    The highly complex and unique mycobacterial cell wall is critical to the survival of Mycobacteria in host cells. However, the biosynthetic pathways responsible for its synthesis are, in general, incompletely characterized. Rv3802c from Mycobacterium tuberculosis is a partially characterized phospholipase/thioesterase encoded within a genetic cluster dedicated to the synthesis of core structures of the mycobacterial cell wall, including mycolic acids and arabinogalactan. Enzymatic assays performed with purified recombinant proteins Rv3802c and its close homologs from Mycobacterium smegmatis (MSMEG{_}6394) and Corynebacterium glutamicum (NCgl2775) show that they all have significant lipase activities that are inhibited by tetrahydrolipstatin, an anti-obesity drug that coincidently inhibits mycobacterial cell wall biosynthesis. The crystal structure of MSMEG{_}6394, solved to 2.9 {angstrom} resolution, revealed an {alpha}/{beta} hydrolase fold and a catalytic triad typically present in esterases and lipases. Furthermore, we demonstrate direct evidence of gene essentiality in M. smegmatis and show the structural consequences of loss of MSMEG{_}6394 function on the cellular integrity of the organism. These findings, combined with the predicted essentiality of Rv3802c in M. tuberculosis, indicate that the Rv3802c family performs a fundamental and indispensable lipase-associated function in mycobacteria.

  13. Analysing the eosinophil cationic protein - a clue to the function of the eosinophil granulocyte

    PubMed Central

    2011-01-01

    Eosinophil granulocytes reside in respiratory mucosa including lungs, in the gastro-intestinal tract, and in lymphocyte associated organs, the thymus, lymph nodes and the spleen. In parasitic infections, atopic diseases such as atopic dermatitis and asthma, the numbers of the circulating eosinophils are frequently elevated. In conditions such as Hypereosinophilic Syndrome (HES) circulating eosinophil levels are even further raised. Although, eosinophils were identified more than hundred years ago, their roles in homeostasis and in disease still remain unclear. The most prominent feature of the eosinophils are their large secondary granules, each containing four basic proteins, the best known being the eosinophil cationic protein (ECP). This protein has been developed as a marker for eosinophilic disease and quantified in biological fluids including serum, bronchoalveolar lavage and nasal secretions. Elevated ECP levels are found in T helper lymphocyte type 2 (atopic) diseases such as allergic asthma and allergic rhinitis but also occasionally in other diseases such as bacterial sinusitis. ECP is a ribonuclease which has been attributed with cytotoxic, neurotoxic, fibrosis promoting and immune-regulatory functions. ECP regulates mucosal and immune cells and may directly act against helminth, bacterial and viral infections. The levels of ECP measured in disease in combination with the catalogue of known functions of the protein and its polymorphisms presented here will build a foundation for further speculations of the role of ECP, and ultimately the role of the eosinophil. PMID:21235798

  14. Neuroimaging studies of striatum in cognition part II: Parkinson's disease

    PubMed Central

    Hanganu, Alexandru; Provost, Jean-Sebastien; Monchi, Oury

    2015-01-01

    In recent years a gradual shift in the definition of Parkinson's disease (PD) has been established, from a classical akinetic-rigid movement disorder to a multi-system neurodegenerative disease. While the pathophysiology of PD is complex and goes much beyond the nigro-striatal degeneration, the striatum has been shown to be responsible for many cognitive functions. Patients with PD develop impairments in multiple cognitive domains and the PD model is probably the most extensively studied regarding striatum dysfunction and its influence on cognition. Up to 40% of PD patients present cognitive impairment even in the early stages of disease development. Thus, understanding the key patterns of striatum and connecting regions' influence on cognition will help develop more specific approaches to alleviate cognitive impairment and slow down its decline. This review focuses on the contribution of neuroimaging studies in understanding how striatum impairment affects cognition in PD. PMID:26500512

  15. Manganese-Enhanced MRI: An Exceptional Tool in Translational Neuroimaging

    PubMed Central

    Silva, Afonso C.; Bock, Nicholas A.

    2008-01-01

    The metal manganese is a potent magnetic resonance imaging (MRI) contrast agent that is essential in cell biology. Manganese-enhanced magnetic resonance imaging (MEMRI) is providing unique information in an ever-growing number of applications aimed at understanding the anatomy, the integration, and the function of neural circuits both in normal brain physiology as well as in translational models of brain disease. A major drawback to the use of manganese as a contrast agent, however, is its cellular toxicity. Therefore, paramount to the successful application of MEMRI is the ability to deliver Mn2+ to the site of interest using as low a dose as possible while preserving detectability by MRI. In the present work, the different approaches to MEMRI in translational neuroimaging are reviewed and challenges for future identified from a practical standpoint. PMID:18550591

  16. Neuroimaging: a story of physicians and basic scientists.

    PubMed

    Lucignani, Giovanni; Bastianello, Stefano

    2006-01-01

    Until just a few decades ago, it was very difficult to detect, non invasively, physiological signals from the brain. However, the discoveries in physics, the evolution of information technology, and the invention of non-invasive biomedical technologies in the last decades of the twentieth century transformed this scenario and created numerous opportunities for studying the brain in living subjects. The authors trace the extraordinary evolution of brain imaging techniques (magnetic resonance imaging, emission tomography, and ?functional neuroimaging?) in the second part of the twentieth century. Not only have these methods had a remarkable clinical impact, they have also been outstanding research tools in the field of the neurosciences. In their most recent applications, they are employed in the quest to uncover the neuronal substrate of the human mind.

  17. Working memory circuit as a function of increasing age in healthy adolescence: A systematic review and meta-analyses.

    PubMed

    Andre, Julia; Picchioni, Marco; Zhang, Ruibin; Toulopoulou, Timothea

    2016-01-01

    Working memory ability matures through puberty and early adulthood. Deficits in working memory are linked to the risk of onset of neurodevelopmental disorders such as schizophrenia, and there is a significant temporal overlap between the peak of first episode psychosis risk and working memory maturation. In order to characterize the normal working memory functional maturation process through this critical phase of cognitive development we conducted a systematic review and coordinate based meta-analyses of all the available primary functional magnetic resonance imaging studies (n = 382) that mapped WM function in healthy adolescents (10-17 years) and young adults (18-30 years). Activation Likelihood Estimation analyses across all WM tasks revealed increased activation with increasing subject age in the middle frontal gyrus (BA6) bilaterally, the left middle frontal gyrus (BA10), the left precuneus and left inferior parietal gyri (BA7; 40). Decreased activation with increasing age was found in the right superior frontal (BA8), left junction of postcentral and inferior parietal (BA3/40), and left limbic cingulate gyrus (BA31). These results suggest that brain activation during adolescence increased with age principally in higher order cortices, part of the core working memory network, while reductions were detected in more diffuse and potentially more immature neural networks. Understanding the process by which the brain and its cognitive functions mature through healthy adulthood may provide us with new clues to understanding the vulnerability to neurodevelopmental disorders.

  18. Phylogeny and evolution of plant cyclic nucleotide-gated ion channel (CNGC) gene family and functional analyses of tomato CNGCs

    PubMed Central

    Saand, Mumtaz Ali; Xu, You-Ping; Munyampundu, Jean-Pierre; Li, Wen; Zhang, Xuan-Rui; Cai, Xin-Zhong

    2015-01-01

    Cyclic nucleotide-gated ion channels (CNGCs) are calcium-permeable channels that are involved in various biological functions. Nevertheless, phylogeny and function of plant CNGCs are not well understood. In this study, 333 CNGC genes from 15 plant species were identified using comprehensive bioinformatics approaches. Extensive bioinformatics analyses demonstrated that CNGCs of Group IVa were distinct to those of other groups in gene structure and amino acid sequence of cyclic nucleotide-binding domain. A CNGC-specific motif that recognizes all identified plant CNGCs was generated. Phylogenetic analysis indicated that CNGC proteins of flowering plant species formed five groups. However, CNGCs of the non-vascular plant Physcomitrella patens clustered only in two groups (IVa and IVb), while those of the vascular non-flowering plant Selaginella moellendorffii gathered in four (IVa, IVb, I and II). These data suggest that Group IV CNGCs are most ancient and Group III CNGCs are most recently evolved in flowering plants. Furthermore, silencing analyses revealed that a set of CNGC genes might be involved in disease resistance and abiotic stress responses in tomato and function of SlCNGCs does not correlate with the group that they are belonging to. Our results indicate that Group IVa CNGCs are structurally but not functionally unique among plant CNGCs. PMID:26546226

  19. Phylogeny and evolution of plant cyclic nucleotide-gated ion channel (CNGC) gene family and functional analyses of tomato CNGCs.

    PubMed

    Saand, Mumtaz Ali; Xu, You-Ping; Munyampundu, Jean-Pierre; Li, Wen; Zhang, Xuan-Rui; Cai, Xin-Zhong

    2015-12-01

    Cyclic nucleotide-gated ion channels (CNGCs) are calcium-permeable channels that are involved in various biological functions. Nevertheless, phylogeny and function of plant CNGCs are not well understood. In this study, 333 CNGC genes from 15 plant species were identified using comprehensive bioinformatics approaches. Extensive bioinformatics analyses demonstrated that CNGCs of Group IVa were distinct to those of other groups in gene structure and amino acid sequence of cyclic nucleotide-binding domain. A CNGC-specific motif that recognizes all identified plant CNGCs was generated. Phylogenetic analysis indicated that CNGC proteins of flowering plant species formed five groups. However, CNGCs of the non-vascular plant Physcomitrella patens clustered only in two groups (IVa and IVb), while those of the vascular non-flowering plant Selaginella moellendorffii gathered in four (IVa, IVb, I and II). These data suggest that Group IV CNGCs are most ancient and Group III CNGCs are most recently evolved in flowering plants. Furthermore, silencing analyses revealed that a set of CNGC genes might be involved in disease resistance and abiotic stress responses in tomato and function of SlCNGCs does not correlate with the group that they are belonging to. Our results indicate that Group IVa CNGCs are structurally but not functionally unique among plant CNGCs.

  20. MRI findings and cognitive functions in a small cohort of myotonic dystrophy type 1: Retrospective analyses.

    PubMed

    Bajrami, Arsida; Azman, Filiz; Yayla, Vildan; Cagirici, Sultan; Keskinkiliç, Cahit; Sozer, Nejla

    2017-02-01

    Myotonic dystrophy type 1 (DM1) is a progressive multisystemic disease with common cognitive deficits and potential brain involvement in addition to the cardinal muscular and systemic symptoms. Impaired mental function associated with nonspecific pathological findings such as white-matter hyperintense lesions (WMHLs), ventricular enlargement and brain atrophy on brain MRI have been previously reported in DM1 patients. While some studies showed correlation of brain morphological changes with neuropsychological and clinical parameters including CTG repeat sizes and disease severity scales in DM1, others failed. The goal of this study was to retrospectively investigate cranial MR abnormalities, predominantly WMHLs, and their effects on clinical and cognitive deficits in a small, phenotypically or genotypically well-characterized cohort of DM1 patients.

  1. Analyses of gene function in amphioxus embryos by microinjection of mRNAs and morpholino oligonucleotides.

    PubMed

    Holland, Linda Z; Onai, Takayuki

    2011-01-01

    The invertebrate chordate amphioxus (Branchiostoma), which is the most basal living chordate, has become an accepted model for the vertebrate ancestor in studies of development and evolution. Amphioxus resembles vertebrates in regard to morphology, developmental gene expression, and gene function. In addition, the amphioxus genome has representatives of most vertebrate gene families. Although it has not undergone the two rounds of whole genome duplications that occurred early in the vertebrate lineage, the amphioxus genome has retained considerable synteny with vertebrate genomes. Thus, studies of genes and development in amphioxus embryos can reveal the fundamental genetic basis of the vertebrate body plan, giving insights into the developmental mechanisms of such organs as the somites, pharynx, kidney, and the central nervous system. Moreover, amphioxus is very useful for understanding how these characters evolved. This chapter details methods for microinjection of amphioxus eggs with mRNAs or morpholino antisense oligonucleotides to analyze gene networks operating in early development.

  2. Aspects of language in children with ADHD: applying functional analyses to explore language use.

    PubMed

    Mathers, Margaret E

    2006-02-01

    This article reports some outcomes from an exploratory study that compares children diagnosed with ADHD and without language impairment with typically developing children for aspects of language use. Discourse analysis based on a systemic functional linguistics approach is applied to spoken and written samples from three different text types that are supplied by 11 children diagnosed with ADHD and 11 typically developing children. Comparisons of multiple variables most often show differences in use between the groups. Closer examination of these differences shows that relative to the controls, the ADHD group uses fewer strategies of textual organization and more avoidance, tangential, and unrelated meanings and more abandoned utterances and spelling and punctuation errors. Clinical implications suggest that careful linguistic analysis of spoken and written language of children with ADHD cannot only identify the linguistic resources they use within everyday contexts but may also indicate areas where intervention may be beneficial.

  3. Structural and Functional Analyses of a Conserved Hydrophobic Pocket of Flavivirus Methyltransferase*

    PubMed Central

    Dong, Hongping; Liu, Lihui; Zou, Gang; Zhao, Yiwei; Li, Zhong; Lim, Siew Pheng; Shi, Pei-Yong; Li, Hongmin

    2010-01-01

    The flavivirus methyltransferase (MTase) sequentially methylates the N7 and 2′-O positions of the viral RNA cap (GpppA-RNA → m7GpppA-RNA → m7GpppAm-RNA), using S-adenosyl-l-methionine (AdoMet) as a methyl donor. We report here that sinefungin (SIN), an AdoMet analog, inhibits several flaviviruses through suppression of viral MTase. The crystal structure of West Nile virus MTase in complex with SIN inhibitor at 2.0-Å resolution revealed a flavivirus-conserved hydrophobic pocket located next to the AdoMet-binding site. The pocket is functionally critical in the viral replication and cap methylations. In addition, the N7 methylation efficiency was found to correlate with the viral replication ability. Thus, SIN analogs with modifications that interact with the hydrophobic pocket are potential specific inhibitors of flavivirus MTase. PMID:20685660

  4. Isolation of translating ribosomes containing peptidyl-tRNAs for functional and structural analyses.

    PubMed

    Shirole, Nitin; Balasubramanian, Sreeram; Yanofsky, Charles; Cruz-Vera, Luis

    2011-02-25

    Recently, structural and biochemical studies have detailed many of the molecular events that occur in the ribosome during inhibition of protein synthesis by antibiotics and during nascent polypeptide synthesis. Some of these antibiotics, and regulatory nascent polypeptides mostly in the form of peptidyl-tRNAs, inhibit either peptide bond formation or translation termination. These inhibitory events can stop the movement of the ribosome, a phenomenon termed "translational arrest". Translation arrest induced by either an antibiotic or a nascent polypeptide has been shown to regulate the expression of genes involved in diverse cellular functions such as cell growth, antibiotic resistance, protein translocation and cell metabolism. Knowledge of how antibiotics and regulatory nascent polypeptides alter ribosome function is essential if we are to understand the complete role of the ribosome in translation, in every organism. Here, we describe a simple methodology that can be used to purify, exclusively, for analysis, those ribosomes translating a specific mRNA and containing a specific peptidyl-tRNA. This procedure is based on selective isolation of translating ribosomes bound to a biotin-labeled mRNA. These translational complexes are separated from other ribosomes in the same mixture, using streptavidin paramagnetic beads (SMB) and a magnetic field (MF). Biotin-labeled mRNAs are synthesized by run-off transcription assays using as templates PCR-generated DNA fragments that contain T7 transcriptional promoters. T7 RNA polymerase incorporates biotin-16-UMP from biotin-UTP; under our conditions approximately ten biotin-16-UMP molecules are incorporated in a 600 nt mRNA with a 25% UMP content. These biotin-labeled mRNAs are then isolated, and used in in vitro translation assays performed with release factor 2 (RF2)-depleted cell-free extracts obtained from Escherichia coli strains containing wild type or mutant ribosomes. Ribosomes translating the biotin-labeled m

  5. Functional Studies and In Silico Analyses to Evaluate Non-Coding Variants in Inherited Cardiomyopathies

    PubMed Central

    Frisso, Giulia; Detta, Nicola; Coppola, Pamela; Mazzaccara, Cristina; Pricolo, Maria Rosaria; D’Onofrio, Antonio; Limongelli, Giuseppe; Calabrò, Raffaele; Salvatore, Francesco

    2016-01-01

    Point mutations are the most common cause of inherited diseases. Bioinformatics tools can help to predict the pathogenicity of mutations found during genetic screening, but they may work less well in determining the effect of point mutations in non-coding regions. In silico analysis of intronic variants can reveal their impact on the splicing process, but the consequence of a given substitution is generally not predictable. The aim of this study was to functionally test five intronic variants (MYBPC3-c.506-2A>C, MYBPC3-c.906-7G>T, MYBPC3-c.2308+3G>C, SCN5A-c.393-5C>A, and ACTC1-c.617-7T>C) found in five patients affected by inherited cardiomyopathies in the attempt to verify their pathogenic role. Analysis of the MYBPC3-c.506-2A>C mutation in mRNA from the peripheral blood of one of the patients affected by hypertrophic cardiac myopathy revealed the loss of the canonical splice site and the use of an alternative splicing site, which caused the loss of the first seven nucleotides of exon 5 (MYBPC3-G169AfsX14). In the other four patients, we generated minigene constructs and transfected them in HEK-293 cells. This minigene approach showed that MYBPC3-c.2308+3G>C and SCN5A-c.393-5C>A altered pre-mRNA processing, thus resulting in the skipping of one exon. No alterations were found in either MYBPC3-c.906-7G>T or ACTC1-c.617-7T>C. In conclusion, functional in vitro analysis of the effects of potential splicing mutations can confirm or otherwise the putative pathogenicity of non-coding mutations, and thus help to guide the patient's clinical management and improve genetic counseling in affected families. PMID:27834932

  6. Neural correlates of the LSD experience revealed by multimodal neuroimaging.

    PubMed

    Carhart-Harris, Robin L; Muthukumaraswamy, Suresh; Roseman, Leor; Kaelen, Mendel; Droog, Wouter; Murphy, Kevin; Tagliazucchi, Enzo; Schenberg, Eduardo E; Nest, Timothy; Orban, Csaba; Leech, Robert; Williams, Luke T; Williams, Tim M; Bolstridge, Mark; Sessa, Ben; McGonigle, John; Sereno, Martin I; Nichols, David; Hellyer, Peter J; Hobden, Peter; Evans, John; Singh, Krish D; Wise, Richard G; Curran, H Valerie; Feilding, Amanda; Nutt, David J

    2016-04-26

    Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD's marked effects on the visual cortex did not significantly correlate with the drug's other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of "ego-dissolution" and "altered meaning," implying the importance of this particular circuit for the maintenance of "self" or "ego" and its processing of "meaning." Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others.

  7. Neural correlates of the LSD experience revealed by multimodal neuroimaging

    PubMed Central

    Carhart-Harris, Robin L.; Muthukumaraswamy, Suresh; Roseman, Leor; Kaelen, Mendel; Droog, Wouter; Murphy, Kevin; Tagliazucchi, Enzo; Schenberg, Eduardo E.; Nest, Timothy; Orban, Csaba; Leech, Robert; Williams, Luke T.; Williams, Tim M.; Bolstridge, Mark; Sessa, Ben; McGonigle, John; Sereno, Martin I.; Nichols, David; Hobden, Peter; Evans, John; Singh, Krish D.; Wise, Richard G.; Curran, H. Valerie; Feilding, Amanda; Nutt, David J.

    2016-01-01

    Lysergic acid diethylamide (LSD) is the prototypical psychedelic drug, but its effects on the human brain have never been studied before with modern neuroimaging. Here, three complementary neuroimaging techniques: arterial spin labeling (ASL), blood oxygen level-dependent (BOLD) measures, and magnetoencephalography (MEG), implemented during resting state conditions, revealed marked changes in brain activity after LSD that correlated strongly with its characteristic psychological effects. Increased visual cortex cerebral blood flow (CBF), decreased visual cortex alpha power, and a greatly expanded primary visual cortex (V1) functional connectivity profile correlated strongly with ratings of visual hallucinations, implying that intrinsic brain activity exerts greater influence on visual processing in the psychedelic state, thereby defining its hallucinatory quality. LSD’s marked effects on the visual cortex did not significantly correlate with the drug’s other characteristic effects on consciousness, however. Rather, decreased connectivity between the parahippocampus and retrosplenial cortex (RSC) correlated strongly with ratings of “ego-dissolution” and “altered meaning,” implying the importance of this particular circuit for the maintenance of “self” or “ego” and its processing of “meaning.” Strong relationships were also found between the different imaging metrics, enabling firmer inferences to be made about their functional significance. This uniquely comprehensive examination of the LSD state represents an important advance in scientific research with psychedelic drugs at a time of growing interest in their scientific and therapeutic value. The present results contribute important new insights into the characteristic hallucinatory and consciousness-altering properties of psychedelics that inform on how they can model certain pathological states and potentially treat others. PMID:27071089

  8. Ethical concepts and future challenges of neuroimaging: an Islamic perspective.

    PubMed

    Al-Delaimy, Wael K

    2012-09-01

    Neuroscience is advancing at a rapid pace, with new technologies and approaches that are creating ethical challenges not easily addressed by current ethical frameworks and guidelines. One fascinating technology is neuroimaging, especially functional Magnetic Resonance Imaging (fMRI). Although still in its infancy, fMRI is breaking new ground in neuroscience, potentially offering increased understanding of brain function. Different populations and faith traditions will likely have different reactions to these new technologies and the ethical challenges they bring with them. Muslims are approximately one-fifth of world population and they have a specific and highly regulated ethical and moral code, which helps them deal with scientific advances and decision making processes in an Islamically ethical manner. From this ethical perspective, in light of the relevant tenets of Islam, neuroimaging poses various challenges. The privacy of spirituality and the thought process, the requirement to put community interest before individual interest, and emphasis on conscious confession in legal situations are Islamic concepts that can pose a challenge for the use of something intrusive such as an fMRI. Muslim moral concepts such as There shall be no harm inflicted or reciprocated in Islam and Necessities overrule prohibitions are some of the criteria that might appropriately be used to guide advancing neuroscience. Neuroscientists should be particularly prudent and well prepared in implementing neuroscience advances that are breaking new scientific and ethical ground. Neuroscientists should also be prepared to assist in setting the ethical frameworks in place in advance of what might be perceived as runaway applications of technology.

  9. Functional analyses of AmpC beta-lactamase through differential stability.

    PubMed Central

    Beadle, B. M.; McGovern, S. L.; Patera, A.; Shoichet, B. K.

    1999-01-01

    adducts with Y150F were significantly destabilized relative to their WT counterparts, suggesting that this residue plays a role in recognizing the acylated intermediate of the beta-lactamase reaction. Reversible denaturation allows for energetic analyses of the complementarity of AmpC for beta-lactams, through ligand binding, and for itself, through residue substitution. Reversible denaturation may be a useful way to study ligand complementarity to other beta-lactam binding proteins as well. PMID:10493583

  10. Statistical improvements in functional magnetic resonance imaging analyses produced by censoring high-motion data points.

    PubMed

    Siegel, Joshua S; Power, Jonathan D; Dubis, Joseph W; Vogel, Alecia C; Church, Jessica A; Schlaggar, Bradley L; Petersen, Steven E

    2014-05-01

    Subject motion degrades the quality of task functional magnetic resonance imaging (fMRI) data. Here, we test two classes of methods to counteract the effects of motion in task fMRI data: (1) a variety of motion regressions and (2) motion censoring ("motion scrubbing"). In motion regression, various regressors based on realignment estimates were included as nuisance regressors in general linear model (GLM) estimation. In motion censoring, volumes in which head motion exceeded a threshold were withheld from GLM estimation. The effects of each method were explored in several task fMRI data sets and compared using indicators of data quality and signal-to-noise ratio. Motion censoring decreased variance in parameter estimates within- and across-subjects, reduced residual error in GLM estimation, and increased the magnitude of statistical effects. Motion censoring performed better than all forms of motion regression and also performed well across a variety of parameter spaces, in GLMs with assumed or unassumed response shapes. We conclude that motion censoring improves the quality of task fMRI data and can be a valuable processing step in studies involving populations with even mild amounts of head movement.

  11. Structural and functional analyses of DM43, a snake venom metalloproteinase inhibitor from Didelphis marsupialis serum.

    PubMed

    Neves-Ferreira, Ana G C; Perales, Jonas; Fox, Jay W; Shannon, John D; Makino, Débora L; Garratt, Richard C; Domont, Gilberto B

    2002-04-12

    DM43, an opossum serum protein inhibitor of snake venom metalloproteinases, has been completely sequenced, and its disulfide bond pattern has been experimentally determined. It shows homology to human alpha(1)B-glycoprotein, a plasma protein of unknown function and a member of the immunoglobulin supergene family. Size exclusion and dynamic laser light scattering data indicated that two monomers of DM43, each composed of three immunoglobulin-like domains, associated to form a homodimer in solution. Analysis of its glycan moiety showed the presence of N-acetylglucosamine, mannose, galactose, and sialic acid, most probably forming four biantennary N-linked chains. DM43 inhibited the fibrinogenolytic activities of bothrolysin and jararhagin and formed 1:1 stoichiometric stable complexes with both metalloproteinases. DM43 was ineffective against atrolysin C or A. No complex formation was detected between DM43 and jararhagin C, indicating the essential role of the metalloproteinase domain for interaction. Homology modeling based on the crystal structure of a killer cell inhibitory receptor suggested the existence of an I-type Ig fold, a hydrophobic dimerization surface and six surface loops potentially forming the metalloproteinase-binding surface on DM43.

  12. Physiological and Transcriptomic Analyses to Characterize the Function of Fur and Iron Response in Shewanella oneidensis

    SciTech Connect

    Yang, Yunfeng; Harris, Daniel P; Luo, Feng; Wu, Liyou; Parsons, Andrea; Palumbo, Anthony Vito; Zhou, Jizhong

    2008-01-01

    Maintaining iron homeostasis is a key metabolic challenge for most organisms. In many bacterial species, regulation of iron homeostasis is carried out by the global transcriptional regulator Fur. Physiological examination showed that Shewanella oneidensis harboring a fur deletion mutation had deficiencies in both growth and acid tolerance response. However, the fur mutant better tolerated iron-limited environments than the wild-type strain MR-1. Transcriptomic studies comparing the fur mutant and MR-1 confirmed previous findings that iron acquisition systems were highly induced by Fur inactivation. In addition, the temporal gene expression profiling of the fur mutant in response to iron depletion and repletion suggested that a number of genes involved in energy transport were iron-responsive but Fur-independent. Further identification of Fur-independent genes was obtained by generating a gene co-expression network from temporal gene expression profiles. A group of genes is involved in heat shock and has an rpoH-binding site at their promoters, and genes related to anaerobic energy transport has a highly conserved Crp binding site at the promoters. Together, this work provides useful information for the characterization of the function of Fur and the iron response in S. oneidensis.

  13. Identification of a novel antimicrobial peptide from amphioxus Branchiostoma japonicum by in silico and functional analyses.

    PubMed

    Liu, Haohan; Lei, Miaomiao; Du, Xiaoyuan; Cui, Pengfei; Zhang, Shicui

    2015-12-18

    The emergence of multi-drug resistant (MDR) microbes leads to urgent demands for novel antibiotics exploration. We demonstrated a cDNA from amphioxus Branchiostoma japonicum, designated Bjamp1, encoded a protein with features typical of antimicrobial peptides (AMPs), which is not homologous to any AMPs currently discovered. It was found that Bjamp1 was expressed in distinct tissues, and its expression was remarkably up-regulated following challenge with LPS and LTA. Moreover, the synthesized putative mature AMP, mBjAMP1, underwent a coil-to-helix transition in the presence of TFE or SDS, agreeing well with the expectation that BjAMP1 was a potential AMP. Functional assays showed that mBjAMP1 inhibited the growth of all the bacteria tested, and induced membrane/cytoplasmic damage. ELISA indicated that mBjAMP1 was a pattern recognition molecule capable of identifying LPS and LTA. Importantly, mBjAMP1 disrupted the bacterial membranes by a membranolytic mechanism. Additionally, mBjAMP1 was non-cytotoxic to mammalian cells. Collectively, these data indicate that mBjAMP1 is a new AMP with a high bacterial membrane selectivity, rendering it a promising template for the design of novel peptide antibiotics against MDR microbes. It also shows for the first time that use of signal conserved sequence of AMPs is effective identifying potential AMPs across different animal classes.

  14. Identification of a novel antimicrobial peptide from amphioxus Branchiostoma japonicum by in silico and functional analyses

    PubMed Central

    Liu, Haohan; Lei, Miaomiao; Du, Xiaoyuan; Cui, Pengfei; Zhang, Shicui

    2015-01-01

    The emergence of multi-drug resistant (MDR) microbes leads to urgent demands for novel antibiotics exploration. We demonstrated a cDNA from amphioxus Branchiostoma japonicum, designated Bjamp1, encoded a protein with features typical of antimicrobial peptides (AMPs), which is not homologous to any AMPs currently discovered. It was found that Bjamp1 was expressed in distinct tissues, and its expression was remarkably up-regulated following challenge with LPS and LTA. Moreover, the synthesized putative mature AMP, mBjAMP1, underwent a coil-to-helix transition in the presence of TFE or SDS, agreeing well with the expectation that BjAMP1 was a potential AMP. Functional assays showed that mBjAMP1 inhibited the growth of all the bacteria tested, and induced membrane/cytoplasmic damage. ELISA indicated that mBjAMP1 was a pattern recognition molecule capable of identifying LPS and LTA. Importantly, mBjAMP1 disrupted the bacterial membranes by a membranolytic mechanism. Additionally, mBjAMP1 was non-cytotoxic to mammalian cells. Collectively, these data indicate that mBjAMP1 is a new AMP with a high bacterial membrane selectivity, rendering it a promising template for the design of novel peptide antibiotics against MDR microbes. It also shows for the first time that use of signal conserved sequence of AMPs is effective identifying potential AMPs across different animal classes. PMID:26680226

  15. Proteomic and functional analyses of Nelumbo nucifera annexins involved in seed thermotolerance and germination vigor.

    PubMed

    Chu, Pu; Chen, Huhui; Zhou, Yuliang; Li, Yin; Ding, Yu; Jiang, Liwen; Tsang, Edward W T; Wu, Keqiang; Huang, Shangzhi

    2012-06-01

    Annexins are multifunctional proteins characterized by their capacity to bind calcium ions and negatively charged lipids. Although there is increasing evidence implicating their importance in plant stress responses, their functions in seeds remain to be further studied. In this study, we identified a heat-induced annexin, NnANN1, from the embryonic axes of sacred lotus (Nelumbo nucifera Gaertn.) using comparative proteomics approach. Moreover, the expression of NnANN1 increased considerably in response to high-temperature treatment. Quantitative real-time PCR (qRT-PCR) revealed that the transcripts of NnANN1 were detected predominantly during seed development and germination in sacred lotus, implicating a role for NnANN1 in plant seeds. Ectopic expression of NnANN1 in Arabidopsis resulted in enhanced tolerance to heat stress in transgenic seeds. In addition, compared to the wild-type seeds, transgenic seeds ectopically expressing NnANN1 exhibited improved resistance to accelerated aging treatment used for assessing seed vigor. Furthermore, transgenic seeds showed enhanced peroxidase activities, accompanied with reduced lipid peroxidation and reduced ROS release levels compared to the wild-type seeds. Taken together, these results indicate that NnANN1 plays an important role in seed thermotolerance and germination vigor.

  16. Functional analyses of cellulose synthase genes in flax (Linum usitatissimum) by virus-induced gene silencing.

    PubMed

    Chantreau, Maxime; Chabbert, Brigitte; Billiard, Sylvain; Hawkins, Simon; Neutelings, Godfrey

    2015-12-01

    Flax (Linum usitatissimum) bast fibres are located in the stem cortex where they play an important role in mechanical support. They contain high amounts of cellulose and so are used for linen textiles and in the composite industry. In this study, we screened the annotated flax genome and identified 14 distinct cellulose synthase (CESA) genes using orthologous sequences previously identified. Transcriptomics of 'primary cell wall' and 'secondary cell wall' flax CESA genes showed that some were preferentially expressed in different organs and stem tissues providing clues as to their biological role(s) in planta. The development for the first time in flax of a virus-induced gene silencing (VIGS) approach was used to functionally evaluate the biological role of different CESA genes in stem tissues. Quantification of transcript accumulation showed that in many cases, silencing not only affected targeted CESA clades, but also had an impact on other CESA genes. Whatever the targeted clade, inactivation by VIGS affected plant growth. In contrast, only clade 1- and clade 6-targeted plants showed modifications in outer-stem tissue organization and secondary cell wall formation. In these plants, bast fibre number and structure were severely impacted, suggesting that the targeted genes may play an important role in the establishment of the fibre cell wall. Our results provide new fundamental information about cellulose biosynthesis in flax that should facilitate future plant improvement/engineering.

  17. Computational and