A study examining the effects of alcohol on emotion recognition and empathy found that alcohol impaired the recognition of anger, but not other specific emotions.
Participants who drank alcohol reported higher affective empathy, i.e. better communication with other study participants. The study is published in Scientific Reports.
After a person ingests alcohol, it is rapidly absorbed through the stomach and small intestine into the bloodstream. The alcohol then travels to the brain, where it affects the release of neurotransmitters, causing relaxation and reduced inhibition. As blood alcohol concentration increases, judgment, coordination, and reaction time become increasingly impaired. The liver begins to metabolize alcohol, but can only process a limited amount per hour, resulting in excess alcohol circulating in the body.
Alcohol also affects the cardiovascular system by dilating blood vessels, which can create a feeling of warmth while lowering body temperature. In the short term, drinking can increase urine production, leading to dehydration and electrolyte imbalance. The gastrointestinal system can become irritated, leading to nausea or vomiting at higher doses.
As alcohol continues to circulate, it disrupts normal sleep, reducing the restorative REM phase of sleep, although it does make people feel sleepy. As blood alcohol levels begin to decline, some people may experience withdrawal-like symptoms, such as anxiety or irritability.
Study author Lakshmi Kumar and colleagues investigated how an intoxicating dose of alcohol (0.74 g/kg for women and 0.82 g/kg for men) affects cognitive and affective empathy. Because previous studies have been inclusive, they began this study without specific hypotheses about the direction of the expected effect.
The study participants were 156 people who reported drinking at least one day a week and binge drinking at least four times in the past month. The average age of the participants was 23 years old. Thirty-one percent of them were women.
Binge drinking was defined as 5 or more standard alcoholic drinks at a time for men and 4 or more for women. A standard alcoholic drink is a drink containing about 14 grams of pure ethanol. This is roughly equivalent to a small beer (350 ml), a glass of wine (150 ml) or a shot of spirits (45 ml).
The participants were randomly assigned to groups of 3 strangers. Each of these groups of three people was randomly assigned to drink either an alcoholic drink or a placebo drink. Thus, 117 participants were assigned to drink alcohol and 39 to drink the placebo drink. However, the participants did not know which drink they were going to drink - they all believed that they were going to drink alcohol.
The alcoholic drink was a cranberry-vodka cocktail, dosed for each participant to achieve a peak blood alcohol concentration of 0.08%. The placebo drink was diluted with water, and the study authors showed these participants fake blood alcohol level recordings to maintain their belief that they were drinking alcohol.
After drinking the designated drink, participants completed 3 assessments of subjective intoxication experience and blood alcohol level (using a breathalyzer) at 30-minute intervals. As blood alcohol level increased after drinking, participants completed assessments of empathy and emotion recognition.
The results showed that participants who had drunk alcohol had impaired recognition of anger, but not other specific emotions. They reported higher affective empathy, i.e. that they relate well to another participant, in response to direct interactions with other participants.
“The results indicate that alcohol impairs anger recognition and increases perceptions of relating to another“, the study authors conclude.
The study adds to the scientific understanding of the psychological effects of alcohol. However, the study authors note that participants interacted in groups of strangers (other study participants with whom they had not previously been acquainted) before completing the emotion recognition and empathy assessments. Differences in these interactions could influence participants' levels of engagement and subsequently reported empathy.
The analysis, titled “Acute Effects of Alcohol on Emotion Recognition and Empathy in Young Heavy Drinkers“, was written by Lakshmi Kumar, Casey G. Creswell, Kirk W. Brown, Greta Lyons, and Brooke K. Feeney.