Cortical Beta Oscillatory Activity Evoked during Reactive Balance Recovery Scales with Perturbation Difficulty and Individual Balance Ability

• Type of Material: Article
• Authors: Nina J. Ghosn, Georgia Institute of Technology; Jacqueline A. Palmer, Emory University; Michael Borich, Emory University; Lena Ting, Emory University; Aiden M. Payne, Emory University
• Language: English
• Date: 2020-11-16
• Publisher: MDPI AG
• Publication Version: Final Published Version
• Copyright Statement: © 2020 by the authors.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.3390/brainsci10110860
• Title of Journal or Parent Work: Brain Sciences
• Volume: 10
• Issue: 11
• Grant/Funding Information: This research was supported by the Eunice Kennedy Shriver National Institutes of Child Health & Human Development of the National Institutes of Health [R01 HD46922-10, F32HD096816, K12HD055931], the National Institute of Neurological Disorders and Stroke of the National Institutes of Health [1P50NS098685], the National Institute on Drug Abuse of the National Institutes of Health [5T90DA032466], the Division of Emerging Frontiers and Multidisciplinary Activities at the National Science Foundation (1137229), the Georgia Tech Neural Engineering Center, the President’s Undergraduate Research Award provided by the Undergraduate Research Opportunities Program at Georgia Tech, and the Andy Zebrowitz Memorial Brain Research Fellowship Award (2017–2018).
• Keywords: skill; EEG; walking
• Research Categories: Biology, Physiology; Biology, Neuroscience

Abstract

Cortical beta oscillations (13–30 Hz) reflect sensorimotor processing, but are not well understood in balance recovery. We hypothesized that sensorimotor cortical activity would increase under challenging balance conditions. We predicted greater beta power when balance was challenged, either by more difficult perturbations or by lower balance ability. In 19 young adults, we measured beta power over motor cortical areas (electroencephalography, Cz electrode) during three magnitudes of backward support -surface translations. Peak beta power was measured during early (50–150 ms), late (150–250 ms), and overall (0–400 ms) time bins, and wavelet-based analyses quantified the time course of evoked beta power. An ANOVA was used to compare peak beta power across perturbation magnitudes in each time bin. We further tested the association between perturbation-evoked beta power and individual balance ability measured in a challenging beam walking task. Beta power increased ~50 ms after perturbation, and to a greater extent in larger perturbations. Lower individual balance ability was associated with greater beta power in only the late (150–250 ms) time bin. These findings demonstrate greater sensorimotor cortical engagement under more challenging balance conditions, which may provide a biomarker for reduced automaticity in balance control that could be used in populations with neurological impairments.