Mind Research Network
Mind Research Network
White T.,Erasmus Medical Center |
Schmidt M.,Erasmus Medical Center |
Kim D.I.,Mind Research Network |
Calhoun V.D.,Mind Research Network |
Calhoun V.D.,University of New Mexico
Cerebral Cortex | Year: 2011
Children and adolescents who develop schizophrenia tend to have greater symptom severity than adults who develop the illness. Since the brain continues to mature into early adulthood, developmental differences in brain structure and function may provide clues to the underlying neurobiology of schizophrenia. With an emerging body of evidence supporting disrupted connectivity contributing to the underlying pathophysiology of schizophrenia, it was our goal to assess differences in functional connectivity in children and adolescents who develop schizophrenia. Participants included a total of 28 children and adolescents (14 patients with schizophrenia and 14 age- and gender-matched controls). All subjects underwent a functional magnetic resonance imaging scan involving a modified Sternberg Item Recognition Paradigm with 3 working memory (WkM) loads. Patients had poorer performance at all 3 WkM loads without a load by diagnosis interaction. Functional imaging results demonstrated 3 specific brain networks disrupted in children and adolescents with schizophrenia. These networks include 1) the anterior cingulate and the temporal lobes, bilaterally; 2) the cerebellum with subcortical regions; and 3) the occipital lobe and the cerebellum. Patients with early-onset schizophrenia demonstrate abnormal functional connectivity in networks involving limbic, temporal lobe, cerebellum, and early visual processing streams. © 2010 The Author.
Allen E.A.,Mind Research Network |
Allen E.A.,Kg Jebsen Center For Research On Neuropsychiatric Disorders And |
Allen E.A.,University of Bergen |
Damaraju E.,Mind Research Network |
And 7 more authors.
Cerebral Cortex | Year: 2014
Spontaneous fluctuations are a hallmark of recordings of neural signals, emergent over time scales spanning milliseconds and tens of minutes. However, investigations of intrinsic brain organization based on resting-state functional magnetic resonance imaging have largely not taken into account the presence and potential of temporal variability, as most current approaches to examine functional connectivity (FC) implicitly assume that relationships are constant throughout the length of the recording. In this work, we describe an approach to assess whole-brain FC dynamics based on spatial independent component analysis, sliding time window correlation, and k-means clustering of windowed correlation matrices. The method is applied to resting-state data from a large sample (n = 405) of young adults. Our analysis of FC variability highlights particularly flexible connections between regions in lateral parietal and cingulate cortex, and argues against a labeling scheme where such regions are treated as separate and antagonistic entities. Additionally, clustering analysis reveals unanticipated FC states that in part diverge strongly from stationary connectivity patterns and challenge current descriptions of interactions between large-scale networks. Temporal trends in the occurrence of different FC states motivate theories regarding their functional roles and relationships with vigilance/arousal. Overall, we suggest that the study of time-varying aspects of FC can unveil flexibility in the functional coordination between different neural systems, and that the exploitation of these dynamics in further investigations may improve our understanding of behavioral shifts and adaptive processes. © 2012 The Author.
Schacht J.P.,Medical University of South Carolina |
Hutchison K.E.,University of Colorado at Boulder |
Hutchison K.E.,Mind Research Network |
Filbey F.M.,University of Texas at Dallas
Neuropsychopharmacology | Year: 2012
Heavy cannabis users display smaller amygdalae and hippocampi than controls, and genetic variation accounts for a large proportion of variance in liability to cannabis dependence (CD). A single nucleotide polymorphism in the cannabis receptor-1 gene (CNR1), rs2023239, has been associated with CD diagnosis and intermediate phenotypes, including abstinence-induced withdrawal, cue-elicited craving, and parahippocampal activation to cannabis cues. This study compared hippocampal and amygdalar volumes (potential CD intermediate phenotypes) between heavy cannabis users and healthy controls, and analyzed interactions between group, rs2023239 variation, and the volumes of these structures. Ninety-four heavy cannabis users participated, of whom 37 (14 men, 23 women; mean age27.8) were matched to 37 healthy controls (14 men, 23 women; mean age27.3) for case-control analyses. Controlling for total intracranial volume and other confounding variables, matched cannabis users had smaller bilateral hippocampi (left, p=0.002; right, p=0.001) and left amygdalae (p=0.01) than controls. When genotype was considered in the case-control analyses, there was a group by genotype interaction, such that the rs2023239 G allele predicted lower volume of bilateral hippocampi among cannabis users relative to controls (both p=0.001). This interaction persisted when all 94 cannabis users were compared to controls. There were no group by genotype interactions on amygdalar volume. These data replicate previous findings of reduced hippocampal and amygdalar volume among heavy cannabis users, and suggest that CNR1 rs2023239 variation may predispose smaller hippocampal volume after heavy cannabis use. This association should be tested in future studies of brain volume differences in CD. © 2012 American College of Neuropsychopharmacology. All rights reserved.
Huster R.J.,Carl von Ossietzky University |
Debener S.,Carl von Ossietzky University |
Eichele T.,University of Bergen |
Eichele T.,Mind Research Network |
Herrmann C.S.,Carl von Ossietzky University
Journal of Neuroscience | Year: 2012
The simultaneous recording and analysis of electroencephalography (EEG) and fMRI data in human systems, cognitive and clinical neurosciences is rapidly evolving and has received substantial attention. The significance of multimodal brain imaging is documented by a steadily increasing number of laboratories now using simultaneous EEG-fMRI aiming to achieve both high temporal and spatial resolution of human brain function. Due to recent developments in technical and algorithmic instrumentation, the rate-limiting step in multimodal studies has shifted from data acquisition to analytic aspects. Here, we introduce and compare different methods for data integration and identify the benefits that come with each approach, guiding the reader toward an understanding and informed selection of the integration approach most suitable for addressing a particular research question. © 2012 the authors.
Anderson N.E.,Mind Research Network |
Kiehl K.A.,Mind Research Network
Trends in Cognitive Sciences | Year: 2012
Psychopaths commit a disproportionate amount of violent crime, and this places a substantial economic and emotional burden on society. Elucidation of the neural correlates of psychopathy may lead to improved management and treatment of the condition. Although some methodological issues remain, the neuroimaging literature is generally converging on a set of brain regions and circuits that are consistently implicated in the condition: the orbitofrontal cortex, amygdala, and the anterior and posterior cingulate and adjacent (para)limbic structures. We discuss these findings in the context of extant theories of psychopathy and highlight the potential legal and policy implications of this body of work. © 2011 Elsevier Ltd.
Turner J.A.,Mind Research Network |
Laird A.R.,University of Texas Health Science Center at San Antonio
Neuroinformatics | Year: 2012
We present the basic structure of the Cognitive Paradigm Ontology (CogPO) for human behavioral experiments. While the experimental psychology and cognitive neuroscience literature may refer to certain behavioral tasks by name (e.g., the Stroop paradigm or the Sternberg paradigm) or by function (a working memory task, a visual attention task), these paradigms can vary tremendously in the stimuli that are presented to the subject, the response expected from the subject, and the instructions given to the subject. Drawing from the taxonomy developed and used by the BrainMap project (www.brainmap.org) for almost two decades to describe key components of published functional imaging results, we have developed an ontology capable of representing certain characteristics of the cognitive paradigms used in the fMRI and PET literature. The Cognitive Paradigm Ontology is being developed to be compliant with the Basic Formal Ontology (BFO), and to harmonize where possible with larger ontologies such as RadLex, NeuroLex, or the Ontology of Biomedical Investigations (OBI). The key components of CogPO include the representation of experimental conditions focused on the stimuli presented, the instructions given, and the responses requested. The use of alternate and even competitive terminologies can often impede scientific discoveries. Categorization of paradigms according to stimulus, response, and instruction has been shown to allow advanced data retrieval techniques by searching for similarities and contrasts across multiple paradigm levels. The goal of CogPO is to develop, evaluate, and distribute a domain ontology of cognitive paradigms for application and use in the functional neuroimaging community. © Springer Science+Business Media, LLC 2011.
Littlewood R.A.,Mind Research Network |
Vanable P.A.,Syracuse University
Current HIV/AIDS Reports | Year: 2011
Complementary and alternative medicine (CAM) is a popular adjunct to conventional medicine across medical populations, and is particularly relevant in the global HIV epidemic. Use of antiretroviral therapy (ART) to treat HIV is ubiquitous in high-resource areas and efforts to increase coverage in low-resource areas are underway. To better understand the role of CAM in HIV treatment and the implications of CAM use for ART uptake and adherence, we review international research published between 2007 and 2011. Findings confirm that CAM is commonly used as an adjunct to ART; however, in countries where ART is less accessible, many HIV-positive individuals take a pluralistic approach to health care, incorporating both traditional and, when available, conventional medicine. The reviewed studies provide no consensus on whether the use of CAM interferes with ART uptake or adherence; instead, research suggests that illness-related behaviors are driven by multiple factors and determined, at least in part, by the availability and accessibility of ART. © 2011 Springer Science+Business Media, LLC.
McEachern A.D.,Mind Research Network |
Snyder J.,Wichita State University
Journal of Abnormal Child Psychology | Year: 2012
This study investigated gender differences in the relationship of early physical and relational aggression to later peer rejection and overt and covert antisocial behaviors. Significant gender differences were found indicating physically aggressive boys were more likely than girls to experience later peer rejection. Early physical aggression was related to later overt antisocial behavior for boys and girls, and more strongly for girls than for boys. Early relational aggression was not associated with later forms of antisocial behavior. In the context of early physical aggression, for boys and girls peer rejection generally served to increment risk for later overt and covert antisocial behavior in an additive fashion. The data suggest some gender specificity in the social risk processes associated with the development of early overt and covert antisocial behaviors. © Springer Science+Business Media, LLC 2011.
Johnson C.,Sandia National Laboratories |
Schwindt P.D.D.,Sandia National Laboratories |
Weisend M.,Mind Research Network
Applied Physics Letters | Year: 2010
The authors have detected magnetic fields from the human brain with a compact, fiber-coupled rubidium spin-exchange-relaxation-free magnetometer. Optical pumping is performed on the D1 transition and Faraday rotation is measured on the D2 transition. The beams share an optical axis, with dichroic optics preparing beam polarizations appropriately. A sensitivity of <5 fT/ Hz is achieved. Evoked responses resulting from median nerve and auditory stimulation were recorded with the atomic magnetometer. Recordings were validated by comparison with those taken by a commercial magnetoencephalography system. The design is amenable to arraying sensors around the head, providing a framework for noncryogenic, whole-head magnetoencephalography. © 2010 American Institute of Physics.
Anderson N.E.,Mind Research Network |
Stanford M.S.,Baylor University
Psychophysiology | Year: 2012
Psychopaths exhibit abnormalities processing emotional information, but there is less certainty regarding the role attention plays in these processes. We present data from two affective picture-viewing tasks comparing event-related potential (ERP) modulation effects when emotional information is present but not task relevant (Task 1) followed by a condition directing attention to the categorization of emotional content (Task 2). Controls show a robust, persistent ERP positivity (200-900ms) associated with emotional target photos compared to neutral targets in both tasks. Individuals with psychopathy only showed this differentiation when explicitly attending to the emotional content of the photos (Task 2), and these effects remained smaller than the amplitude differences demonstrated by controls. Although abnormal allocation of attention may play a critical role, this cannot completely account for emotional processing deficits associated with psychopathy. © 2012 Society for Psychophysiological Research.