Mapping brain asymmetry in health and disease through the ENIGMA consortium

• Authors: Xiang-Zhen Kong, Max Planck Institute for Psycholinguistics; Merel C Postema, Max Planck Institute for Psycholinguistics; Tulio Guadalupe, Max Planck Institute for Psycholinguistics; Carolien de Kovel, Max Planck Institute for Psycholinguistics; Premika SW Boedhoe, Vrije Universiteit Amsterdam; Martine Hoogman, Radboud University Nijmegen; Samuel R Mathias, Boston Childrens Hospital; Daan van Rooij, Radboud University Nijmegen; Dick Schijven, Max Planck Institute for Psycholinguistics; David C Glahn, Boston Childrens Hospital; Sarah E Medland, QIMR Berghofer Medical Research Institute; Neda Jahanshad, University of Southern California; Sophia I Thomopoulos, University of Southern California; Jessica A Turner, Emory University; Jan Buitelaar, Radboud University Nijmegen; Theo GM van Erp, University of California Irvine; Barbara Franke, Radboud University Nijmegen; Simon E Fisher, Max Planck Institute for Psycholinguistics; Odile A van den Heuvel, Vrije Universiteit Amsterdam; Lianne Schmaal, Orygen, The National Centre of Excellence in Youth Mental Health; Paul M Thompson, Emory University; Clyde Francks, Max Planck Institute for Psycholinguistics
• Journal Title: HUMAN BRAIN MAPPING
• Volume: Volume 43, Number 1
• Publisher: WILEY | 2020-05-18, Pages 167-181
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1002/hbm.25033
• Subjects: Psychology, Behavioral; Health Sciences, Mental Health
• Keywords: Science & Technology; Life Sciences & Biomedicine; Neurosciences; Neuroimaging; Radiology, Nuclear Medicine & Medical Imaging; Neurosciences & Neurology; autism spectrum disorder; brain asymmetry; brain laterality; major depressive disorder; mega-analysis; meta-analysis; obsessive-compulsive disorder; structural imaging; OBSESSIVE-COMPULSIVE DISORDER; AUTISM SPECTRUM DISORDER; FRONTAL EEG ASYMMETRY; HUMAN CEREBRAL-CORTEX; FUNCTIONAL LATERALIZATION; HEMISPHERIC-ASYMMETRY; MAGNETIC-RESONANCE; CORTICAL THICKNESS; SPATIAL ATTENTION; ALPHA ASYMMETRY

Abstract

Left–right asymmetry of the human brain is one of its cardinal features, and also a complex, multivariate trait. Decades of research have suggested that brain asymmetry may be altered in psychiatric disorders. However, findings have been inconsistent and often based on small sample sizes. There are also open questions surrounding which structures are asymmetrical on average in the healthy population, and how variability in brain asymmetry relates to basic biological variables such as age and sex. Over the last 4 years, the ENIGMA-Laterality Working Group has published six studies of gray matter morphological asymmetry based on total sample sizes from roughly 3,500 to 17,000 individuals, which were between one and two orders of magnitude larger than those published in previous decades. A population-level mapping of average asymmetry was achieved, including an intriguing fronto-occipital gradient of cortical thickness asymmetry in healthy brains. ENIGMA's multi-dataset approach also supported an empirical illustration of reproducibility of hemispheric differences across datasets. Effect sizes were estimated for gray matter asymmetry based on large, international, samples in relation to age, sex, handedness, and brain volume, as well as for three psychiatric disorders: autism spectrum disorder was associated with subtly reduced asymmetry of cortical thickness at regions spread widely over the cortex; pediatric obsessive–compulsive disorder was associated with altered subcortical asymmetry; major depressive disorder was not significantly associated with changes of asymmetry. Ongoing studies are examining brain asymmetry in other disorders. Moreover, a groundwork has been laid for possibly identifying shared genetic contributions to brain asymmetry and disorders.