Distinct cortical correlates of perception and motor function in balance control

• Type of Material: Article
• Authors: Jasmine Mirdamadi, Emory University; Lena Ting, Emory University; Michael R. Borich, Emory University
• Language: English
• Date: 2023-08-23
• Publisher: NIH
• Publication Version: Preprint (Prior to Peer Review)
• Copyright Statement: The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.
• License: Creative Commons Attribution-NoDerivs 4.0 International
• Final Published Version (URL): https://doi.org/10.1101%2F2023.08.22.554282
• Title of Journal or Parent Work: bioRxiv
• Grant/Funding Information: This work was supported by National Institutes of Health Eunice Kennedy Shriver National Institutes of Child Health & Human Development (F32HD105458 to JLM), National Institute of Neurological Disorders and Stroke (5T32NS007480-15 to JLM), and National Institute on Aging (R01 AG072756 to LHT and MRB).
• Keywords: Cortical sensorimotor signals; brain state; eletroencephalography
• Research Categories: Biology, Neuroscience

Abstract

Fluctuations in brain state alter how we perceive our body and generate movements but have not been investigated in functional whole-body behaviors. During reactive balance control, we recently showed that evoked brain activity is associated with balance ability in healthy young individuals. Further, in individuals with Parkinson’s disease, impairments in whole-body motion perception in reactive balance are associated with clinical balance impairment. Here we investigated brain activity during whole-body motion perception in reactive balance in healthy young adults. We hypothesized that flexibility in brain states underlies successful perception and movement during whole-body movement. We characterized two cortical sensorimotor signals using electroencephalography localized to the supplementary motor area: 1) the “N1 response”, a perturbation-evoked potential that decreases in amplitude with expectancy and is larger in individuals with lower balance function; and 2) pre-perturbation beta oscillatory activity, a rhythm that favors maintenance of the current sensorimotor state and is inversely associated with perception in seated somatosensory perceptual tasks. In a two-alternative forced choice task, participants judged whether pairs of backward support-surface perturbations during standing were in the “same” or “different” direction. As expected, lower whole-body perception was associated with lower balance ability. Within a perturbation pair, N1 attenuation was larger on correctly perceived trials and associated with better balance, but not perception. In contrast, pre-perturbation beta power was higher on incorrectly perceived trials and associated with poorer perception, but not balance. Taken together, flexibility in different cortical processes influences perceptual accuracy but have distinct associations with balance and perceptual ability.