Posterior Alpha Power During Working Memory Maintenance in Alcohol Use Disorder

Abstract

Individuals with alcohol use disorder (AUD) display modest neurobehavioral deficits on cognitive tasks such as working memory (WM). Neurophysiology (i.e. posterior alpha power) during the maintenance phase of a WM task was compared. Healthy controls (HC, n=50) and newly abstinent individuals with AUD (n=42) completed a directed attend/ignore WM task. Spectral alpha power was extracted from the posterior portion of the scalp. A mixed linear model compared posterior alpha power controlling for alpha power in a baseline condition between group (HC vs. AUD) and sex (male vs. female). Main effects for group (p=.01) and sex (p=.003) were significant. HC displayed a higher alpha power compared to that of individuals with AUD. Males also presented with higher alpha power compared to women. There was no significant interaction between group and sex. An exploratory analysis to determine a relationship between alpha power and performance on the task was conducted and a differential relationship between groups (p<.001) was found. There was no significant relationship between performance and spectral power for HC, but a negative relationship was found for individuals with AUD. Higher alpha power was associated with decreased accuracy (p=.09). Individuals with AUD display a lower alpha power compared to HC, and this is associated with increased accuracy. Whether this signifies a compensatory mechanism remains a question intended for investigation.