Low-alcohol doses reduce common 10- to 15-Hz input to bilateral leg muscles during quiet standing.
The effects of low doses of alcohol on neural synchronization in muscular activity were investigated in ten participants during quiet standing with eyes open or closed. We focused on changes in common input to bilateral motor unit pools as evident in surface electromyographic (EMG) recordings of lower leg extensor and flexor muscles. The extensor muscles exhibited bilateral synchronization in two distinct frequency bands (i.e., 0-5 and 10-15 Hz), whereas synchronization between flexor muscles was minimal. As expected, alcohol ingestion affected postural sway, yielding increased sway at higher blood-alcohol levels. Whereas vision affected bilateral synchronization only at 0-5 Hz, alcohol ingestion resulted in a progressive decrease of synchronization at 10-15 Hz between the EMG activities of the extensor muscles. The decrease in common bilateral input is most likely related to reduced reticulospinal activity with alcohol ingestion.
Boonstra
T W
TW
Research Institute MOVE, Faculty of Human Movement Sciences, VU University Amsterdam, The Netherlands. t.boonstra@unsw.edu.au
Roerdink
M
M
Daffertshofer
A
A
van Vugt
B
B
van Werven
G
G
Beek
P J
PJ
D000328:Adult; D000704:Analysis of Variance; D002492:Central Nervous System Depressants / Q000097:blood / Q000494:pharmacology*; D003627:Data Interpretation, Statistical; D004305:Dose-Response Relationship, Drug; D004576:Electromyography; D000431:Ethanol / Q000097:blood / Q000494:pharmacology*; D006801:Humans; D007866:Leg / Q000294:innervation / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000294:innervation / Q000502:physiology*; D004856:Postural Balance / Q000187:drug effects* / Q000502:physiology; D011187:Posture / Q000502:physiology
D002492:Central Nervous System Depressants; D000431:Ethanol