Cortical inhibition is theorized to reflect an underlying property of human brain function, sharpening tuning and shaping connectivity. Although age and sex effects on large-scale resting-state brain connectivity have been well documented, effects on local cortical inhibition have received relatively limited attention. Here, we evaluated age and sex effects on presumed local inhibitory interactions in 6 lateral cortical areas using resting-state functional magnetic resonance imaging (fMRI) data acquired from 1054 young adults who participated in the Human Connectome Project. For each area, all possible pairwise crosscorrelations between prewhitened blood oxygenation level-dependent (BOLD) time series were calculated, and the highest value (CCmax) was retained to determine the mean and percentage of negative and positive CCmax. Here, we focused on the percentage of negative CCmax which we referred to as presumed “percent inhibition”. The results documented regional differences in percent inhibition as well as age and sex effects, such that women’s brains were characterized by significantly higher percent inhibition than men overall and in 4 of the 6 cortical areas, and the percent inhibition increased significantly with age in all 6 areas for women but in only one area for men. The findings from this young adult sample are presumed to reflect ongoing maturational processes involving local network connectivity that may be shaped by sex differences in brain structure, function, and neurochemistry.
Bibliographical noteFunding Information:
Data were provided by the Human Connectome Project, WU-Minn Consortium (Principal Investigators: David Van Essen and Kamil Ugurbil; 1U54MH091657) funded by the 16 National Institutes of Health (NIH) institutes and centers that support the NIH Blueprint for Neuroscience Research and by the McDonnell Center for Systems Neuroscience at Washington University.
Partial funding for this study was provided by the University of Minnesota (the Anita Kunin Chair in Women's Healthy Brain Aging, the Brain and Genomics Fund, the McKnight Presidential Chair of Cognitive Neuroscience, and the American Legion Brain Sciences Chair) and the U.S. Department of Veterans Affairs. The sponsors had no role in the current study design, analysis, or interpretation, or in the writing of this paper. The contents do not represent the views of the U.S. Department of Veterans Affairs or the United States Government.
© 2021, This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.
- Functional magnetic resonance imaging
- Resting state
- Magnetic Resonance Imaging/methods
- Young Adult
- Cerebral Cortex/diagnostic imaging
- Nerve Net/physiology
PubMed: MeSH publication types
- Journal Article