Author
Bryon A. Mueller
Other affiliations: University of Antioquia
Bio: Bryon A. Mueller is an academic researcher from University of Minnesota. The author has contributed to research in topics: Resting state fMRI & Diffusion MRI. The author has an hindex of 43, co-authored 155 publications receiving 7640 citations. Previous affiliations of Bryon A. Mueller include University of Antioquia.
Papers published on a yearly basis
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University of California, Irvine1, University of Southern California2, Yale University3, Oslo University Hospital4, Karolinska Institutet5, University of Oslo6, University of California, San Diego7, University of Göttingen8, Trinity College, Dublin9, National University of Ireland, Galway10, University of Amsterdam11, VU University Amsterdam12, University of Pennsylvania13, San Francisco VA Medical Center14, University of California, San Francisco15, University of Minnesota16, Dresden University of Technology17, Harvard University18, University of New Mexico19, University of Iowa20, Utrecht University21, University of California, Los Angeles22, University of Cantabria23, Northwestern University24, University of Edinburgh25, Osaka University26, Georgia State University27
TL;DR: Worldwide cooperative analyses of brain imaging data support a profile of subcortical abnormalities in schizophrenia, which is consistent with that based on traditional meta-analytic approaches, and validates that collaborative data analyses can readily be used across brain phenotypes and disorders.
Abstract: The profile of brain structural abnormalities in schizophrenia is still not fully understood, despite decades of research using brain scans. To validate a prospective meta-analysis approach to analyzing multicenter neuroimaging data, we analyzed brain MRI scans from 2028 schizophrenia patients and 2540 healthy controls, assessed with standardized methods at 15 centers worldwide. We identified subcortical brain volumes that differentiated patients from controls, and ranked them according to their effect sizes. Compared with healthy controls, patients with schizophrenia had smaller hippocampus (Cohen's d=-0.46), amygdala (d=-0.31), thalamus (d=-0.31), accumbens (d=-0.25) and intracranial volumes (d=-0.12), as well as larger pallidum (d=0.21) and lateral ventricle volumes (d=0.37). Putamen and pallidum volume augmentations were positively associated with duration of illness and hippocampal deficits scaled with the proportion of unmedicated patients. Worldwide cooperative analyses of brain imaging data support a profile of subcortical abnormalities in schizophrenia, which is consistent with that based on traditional meta-analytic approaches. This first ENIGMA Schizophrenia Working Group study validates that collaborative data analyses can readily be used across brain phenotypes and disorders and encourages analysis and data sharing efforts to further our understanding of severe mental illness.
919 citations
The Mind Research Network1, University of Bergen2, University of North Carolina at Chapel Hill3, University of California, San Francisco4, Veterans Health Administration5, University of California, Los Angeles6, University of Minnesota7, Yale University8, University of California, Irvine9, Georgia State University10, University of Iowa11, University of New Mexico12
TL;DR: The results support and expand current knowledge regarding dysconnectivity in schizophrenia, and strongly advocate the use of dynamic analyses to better account for and understand functional connectivity differences.
906 citations
TL;DR: The present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide, and is believed to be the first ever large-scale coordinated study of WM microstructural differences in schizophrenia.
Abstract: The regional distribution of white matter (WM) abnormalities in schizophrenia remains poorly understood, and reported disease effects on the brain vary widely between studies. In an effort to identify commonalities across studies, we perform what we believe is the first ever large-scale coordinated study of WM microstructural differences in schizophrenia. Our analysis consisted of 2359 healthy controls and 1963 schizophrenia patients from 29 independent international studies; we harmonized the processing and statistical analyses of diffusion tensor imaging (DTI) data across sites and meta-analyzed effects across studies. Significant reductions in fractional anisotropy (FA) in schizophrenia patients were widespread, and detected in 20 of 25 regions of interest within a WM skeleton representing all major WM fasciculi. Effect sizes varied by region, peaking at (d=0.42) for the entire WM skeleton, driven more by peripheral areas as opposed to the core WM where regions of interest were defined. The anterior corona radiata (d=0.40) and corpus callosum (d=0.39), specifically its body (d=0.39) and genu (d=0.37), showed greatest effects. Significant decreases, to lesser degrees, were observed in almost all regions analyzed. Larger effect sizes were observed for FA than diffusivity measures; significantly higher mean and radial diffusivity was observed for schizophrenia patients compared with controls. No significant effects of age at onset of schizophrenia or medication dosage were detected. As the largest coordinated analysis of WM differences in a psychiatric disorder to date, the present study provides a robust profile of widespread WM abnormalities in schizophrenia patients worldwide. Interactive three-dimensional visualization of the results is available at www.enigma-viewer.org.
480 citations
TL;DR: This work quantitatively characterize the univariate wavelet entropy of regional activity, the bivariate pairwise functional connectivity between regions, and the multivariate network organization of connectivity patterns, and develops a general statistical framework for the testing of group differences in network properties, broadly applicable to studies where changes in network organization are crucial to the understanding of brain function.
398 citations
TL;DR: Convergent fMRI and DTI findings that are consistent with the disconnection hypothesis in schizophrenia, particularly in medial frontal regions, while adding some insight of the relationship between brain disconnectivity and behavior are shown.
Abstract: Background: Schizophrenia is characterized by a lack of integration between thought, emotion, and behavior. A disruption in the connectivity between brain processes may underlie this schism. Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) were used to evaluate functional and anatomical brain connectivity in schizophrenia. Methods: In all, 29 chronic schizophrenia patients (11 females, age: mean = 41.3, SD = 9.28) and 29 controls (11 females, age: mean = 41.1, SD = 10.6) were recruited. Schizophrenia patients were assessed for severity of negative and positive symptoms and general cognitive abilities of attention/concentration and memory. Participants underwent a resting-fMRI scan and a DTI scan. For fMRI data, a hybrid independent components analysis was used to extract the group default mode network (DMN) and accompanying time-courses. Voxel-wise whole-brain multiple regressions with corresponding DMN time-courses was conducted for each subject. A t-test was conducted on resulting DMN correlation maps to look between-group differences. For DTI data, voxel-wise statistical analysis of the fractional anisotropy data was carried out to look for between-group differences. Voxel-wise correlations were conducted to investigate the relationship between brain connectivity and behavioral measures. Results: Results revealed altered functional and anatomical connectivity in medial frontal and anterior cingulate gyri of schizophrenia patients. In addition, frontal connectivity in schizophrenia patients was positively associated with symptoms as well as with general cognitive ability measures. Discussion: The present study shows convergent fMRI and DTI findings that are consistent with the disconnection hypothesis in schizophrenia, particularly in medial frontal regions, while adding some insight of the relationship between brain disconnectivity and behavior.
348 citations
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TL;DR: A triple network model of aberrant saliency mapping and cognitive dysfunction in psychopathology is proposed, emphasizing the surprising parallels that are beginning to emerge across psychiatric and neurological disorders.
2,712 citations
TL;DR: A survey of factor analytic studies of human cognitive abilities can be found in this paper, with a focus on the role of factor analysis in human cognitive ability evaluation and cognition. But this survey is limited.
Abstract: (1998). Human cognitive abilities: A survey of factor analytic studies. Gifted and Talented International: Vol. 13, No. 2, pp. 97-98.
2,388 citations
Florey Institute of Neuroscience and Mental Health1, University of Calgary2, Boston Medical Center3, University of Zurich4, University of Missouri–Kansas City5, University of Oslo6, International Olympic Committee7, University of Toronto8, University of Michigan9, Vanderbilt University Medical Center10, University of Washington11, University of North Carolina at Chapel Hill12, University of British Columbia13, Burke Rehabilitation Hospital14, Cornell University15, University of Ottawa16, Medical College of Wisconsin17, Monash University18, University of New South Wales19, University of Melbourne20, McMaster University21, University of Medicine and Dentistry of New Jersey22, Princeton University23
TL;DR: The 4th International Conference on Concussion in Sport held in Zurich, November 2012 was attended by Paul McCrory, Willem H Meeuwisse, Mark Aubry, Jiří Dvořák, Ruben J Echemendia, Lars Engebretsen, Karen Johnston, Jeffrey S Kutcher, Martin Raftery, Allen Sills and Kathryn Schneider.
2,293 citations
Florey Institute of Neuroscience and Mental Health1, University of Calgary2, Boston University3, University of Missouri–Kansas City4, International Olympic Committee5, University of Michigan6, Veterans Health Administration7, University of North Carolina at Chapel Hill8, University of British Columbia9, Medical College of Wisconsin10, University of Melbourne11, McMaster University12, Rutgers University13
TL;DR: This paper is a revision and update of the recommendations developed following the 1st (Vienna 2001), 2nd (Prague 2004) and 3rd (Zurich 2008) International Consensus Conferences on Concussions in Sport and is based on the deliberations at the 4th International Conference on Concussion in Sport held in Zurich, November 2012.
Abstract: The new 2012 Zurich Consensus statement is designed to build on the principles outlined in the previous documents and to develop further conceptual understanding of this problem using a formal consensus-based approach. A detailed description of the consensus process is outlined at the end of this document under the Background section. This document is developed primarily for use by physicians and healthcare professionals who are involved in the care of injured athletes, whether at the recreational, elite or professional level.
2,269 citations