whereRU: Aresty Poster 146 - Effect of Alcohol on Nervous System Activity by Aresty Posters 2009

Having a family history of alcohol use disorders (FH+) imparts a fourfold increase in the risk of developing an alcohol use disorder compared individuals who have no such history (FH-). Although there is evidence that FH+ and FH- individuals differ in the effects of alcohol on autonomic activity, sympathetic (SNS) and parasympathetic (PNS) autonomic components have seldom been differentiated. I examined this question in 125 social drinkers who were randomly assigned to an alcohol, placebo, or control beverage group. Skin conductance and pulse transit time (PTT) were indicators of SNS activity, and high-frequency heart rate variability measured PNS activity. Alcohol generally suppressed PNS and activated SNS in both FH+ and FH- groups. FH did not differentially affect PNS activation. However, only FH+ individuals showed a significant decrease in SNS activity following placebo, suggesting an antagonistic placebo response. Results suggest that cognitive expectancies about the effects of alcohol may differentially affect physiology in FH+ and FH- groups.