The Effects Of Acute Alcohol Consumption On Empathy For Pain:An ERP Study

Empathy refers to the ability to understand others’feelings and emotional state and it is an important high-level social emotion. Previous researches indicated that there were two stages in empathy:a bottom-up processing of affective sharing and a top-down processing of cognitive regulation. Alcohol is a popular social beverage. However, a recent functional magnetic resonance imaging (fMRI) study found that empathic neural activity in certain region of empathy network was significantly reduced after alcohol intoxication, compared with those in placebo session indicating that alcohol intoxication may reduce individual’s empathy for others’pain. However, due to a low time resolution of fMRI we cannot know which stage of empathy was influenced by alcohol.Therefore, this study employed Event-Related Potentials (ERPs) to further investigate when and how acute intoxication influenced empathy. A double-blinded within-subjects design was adopted. Twenty-two healthy social drinkers participated in this study. They were asked to watch pictures depicting painful or non-painful situations of body parts carefully in the target trials and perform a pain judgment task in the catch trials either in the alcohol or placebo session. We found that,1) compared to placebo, alcohol significantly reduced N1over occipital area and P1over frontal-central area when processing painful stimulus and reduced LPP over frontal-central area when both processing painful and non-painful stimulus. These results suggested that alcohol specifically suppressed early visual processing for painful stimulus and generally suppressed late controlled cognitive processing.2) Compared to non-painful stimulus, the painful stimulus elicited a more positive shift during N2and LPP over central area in placebo condition while in the alcohol condition, a reverse effect was observed in N2and no significant difference was observed in LPP over central area. The left hemisphere played a dominant role in empathy processing in both situations. These results suggested alcohol suppressed the top-down processing of cognitive evaluation stage of empathy.