Intrinsic Functional Connectivity of the Brain in Adults with a Single Cerebral Hemisphere
A reliable set of functional brain networks is found in healthy people and thought to underlie our cognition, emotion, and behavior. Here, we investigated these networks by quantifying intrinsic functional connectivity in six individuals who had undergone surgical removal of one hemisphere. Hemispherectomy subjects and healthy controls were scanned with identical parameters on the same scanner and compared to a large normative sample (n = 1,482). Surprisingly, hemispherectomy subjects and controls all showed strong and equivalent intrahemispheric connectivity between brain regions typically assigned to the same functional network. Connectivity between parts of different networks, however, was markedly increased for almost all hemispherectomy participants and across all networks. These results support the hypothesis of a shared set of functional networks that underlie cognition and suggest that between-network interactions may characterize functional reorganization in hemispherectomy.
Additional Information© 2019 The Authors. Under a Creative Commons license - Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) Received 8 February 2019, Revised 26 July 2019, Accepted 15 October 2019, Available online 19 November 2019. We thank the participants and their families for their important contribution to our ongoing work on this condition. We thank Monika Jones for great encouragement and organizational support. We thank Dr. Aria Fallah and Dr. H. Westley Phillips for reviewing the hemispherectomy MRIs included in this study. This project was funded in large part by The Brain Recovery Project: Childhood Epilepsy Surgery Foundation. D.K. was in part funded by the Della Martin Foundation for Mental Illness. R.A., J.D., and L.K.P. were funded in part by NSF grant BCS-1845958. B.T.T.Y. is supported by the NUS Strategic Research (DPRT/944/09/14), NUS SOM Aspiration Fund (R185000271720), Singapore NMRC (CBRG/0088/2015), NUS YIA, and the Singapore National Research Foundation (NRF) fellowship (class of 2017). B.F. and this research was supported in part by the BRAIN Initiative Cell Census Network (grant U01MH117023), the National Institute for Biomedical Imaging and Bioengineering (P41EB015896, 1R01EB023281, R01EB006758, R21EB018907, and R01EB019956), the National Institute on Aging (5R01AG008122, R01AG016495, and R56AG064027), and the National Institute for Neurological Disorders and Stroke (R01NS0525851, R21NS072652, R01NS070963, R01NS083534, 5U01NS086625, and R01NS105820), and this study was made possible by the resources provided by shared instrumentation grants 1S10RR023401, 1S10RR019307, and 1S10RR023043. Data were provided in part by Caltech Conte Center for the Neurobiology of Social Decision Making (2P50-MH094258) and the Brain Genomics Superstruct Project of Harvard University and the Massachusetts General Hospital (principal investigators: Randy Buckner, Joshua Roffman, and Jordan Smoller), with support from the Center for Brain Science Neuroinformatics Research Group, the Athinoula A. Martinos Center for Biomedical Imaging, and the Center for Human Genetic Research. 20 individual investigators at Harvard and MGH generously contributed data to the overall project. Author Contributions: D.K., R.A., J.M.T., and L.K.P. designed the experiments; D.K., J.M.T., L.K.P., and R.N. conducted the experiments; D.K., B.F., and B.T.T.Y. analyzed the data; D.K. and R.A. wrote the paper; and J.M.T., B.F., B.T.T.Y., J.D., and L.K.P. provided feedback for analyses and paper. Data and Code Availability: The GSP dataset is available at https://dataverse.harvard.edu/dataverse/GSP (https://doi.org/10.7910/DVN/25833). The Caltech control data is available from (https://openneuro.org/datasets/ds002232). The hemispherectomy data is currently only available upon request due to pending IRB decisions. If the data will be made publicly available in the future, it will be deposited into the Caltech control repository. Code to preprocess and create FC for the GSP data is available at https://github.com/ThomasYeoLab/CBIG, subsequent GSP analyses and code to process Caltech datasets is available from the corresponding author upon request (https://github.com/doritdorit/). Declaration of Interests: B.F. has a financial interest in CorticoMetrics, a company whose medical pursuits focus on brain imaging and measurement technologies. B.F.'s interests were reviewed and are managed by Massachusetts General Hospital and Partners HealthCare in accordance with their conflict of interest policies. All other authors declare no competing interests.
Published - Kliemann_2019_Final.pdf
Accepted Version - nihms-1544231.pdf
Supplemental Material - 1-s2.0-S2211124719313816-mmc1.pdf