A "conscious" loss of balance: directing attention to movement can impair the cortical response to postural perturbations
File(s)
Published version
Author(s)
Parr, Johnny VV
Mills, Richard
Kal, Elmar
Bronstein, Adolfo M
Ellmers, Toby J
Type
Journal Article
Abstract
“Trying too hard” can interfere with skilled movement, such as sports and music playing. Postural control can similarly suffer when conscious attention is directed toward it (“conscious movement processing”; CMP). However, the neural mechanisms through which CMP influences balance remain poorly understood. We explored the effects of CMP on electroencephalographic (EEG) perturbation-evoked cortical responses and subsequent balance performance. Twenty healthy young adults (age = 25.1 ± 5 years; 10 males and 10 females) stood on a force plate-embedded moveable platform while mobile EEG was recorded. Participants completed two blocks of 50 discrete perturbations, containing an even mix of slower (186 mm/s peak velocity) and faster (225 mm/s peak velocity) perturbations. One block was performed under conditions of CMP (i.e., instructions to consciously control balance), while the other was performed under “Control” conditions with no additional instructions. For both slow and fast perturbations, CMP resulted in significantly smaller cortical N1 signals (a perturbation-evoked potential localized to the supplementary motor area) and lower sensorimotor beta EEG activity 200–400 ms postperturbation. Significantly greater peak velocities of the center of pressure (i.e., greater postural instability) were also observed during the CMP condition. Our findings provide the first evidence that disruptions to postural control during CMP may be a consequence of insufficient cortical activation relevant for balance (i.e., insufficient cortical N1 responses followed by enhanced beta suppression). We propose that conscious attempts to minimize postural instability through CMP acts as a cognitive dual-task that dampens the sensitivity of the sensorimotor system for future losses of balance.
Date Issued
2024-11-27
Date Acceptance
2024-09-26
Citation
The Journal of Neuroscience, 2024, 44 (48)
ISSN
0270-6474
Publisher
Society for Neuroscience
Journal / Book Title
The Journal of Neuroscience
Volume
44
Issue
48
Copyright Statement
© 2024 Parr et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license, which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
License URL
Identifier
10.1523/JNEUROSCI.0810-24.2024
Subjects
balance
conscious control
EEG
kinetics
LARGER
Life Sciences & Biomedicine
MUSCLE
N1
Neurosciences
Neurosciences & Neurology
perturbation
posture
PRESSURE
Science & Technology
THREAT
YOUNG
Publication Status
Published
Article Number
e0810242024
Date Publish Online
2024-11-27