Just One Drink Disrupts Ability to Read Emotions, Body Language
Just one glass of wine may be enough to impair your ability to read other people's emotions and body language, according to a new study.
New brain imaging research reveals that one alcoholic drink affects behavior by interrupting communication between the amygdala and parts of the prefrontal cortex, two parts of the brain that control behavior.
Investigators said this breakdown in communication could explain why having a few drinks triggers disinhibition, aggression and social withdrawal symptoms.
The study involved using MRI scans to see what how beverages containing alcohol at 16 percent influences a person's ability to make decisions and read emotions like fear, anger and happiness.
"How the amygdala and prefrontal cortex interact enables us to accurately appraise our environment and modulate our reactions to it," said researcher Dr. Luan Phan, a professor at the University of Illinois and Chicago (UIC) College of Medicine, according to the Daily Mail. "Emotional processing involves both the amygdala and areas of the brain located in the prefrontal cortex responsible for cognition and modulation of behavior."
"This research gives us a much better idea of what is going on in the brain that leads to some of the maladaptive behaviors we see in alcohol intoxication including social disinhibition, aggression and social withdrawal," Phan added.
The latest study involved 12 heavy social drinkers who were on average 23 years of age. Participants were given either an alcoholic drink or a placebo. Afterwards, researchers hooked participants up to fMRI scanners and showed them a series of faces.
Participants' brain activity was monitored while they tried to identify emotions of people in the pictures.
The findings revealed that alcohol reduced the connection between the amygdala and the orbitofrontal cortex when participants were trying to match up angry, fearful and happy faces.
The latest study also supported previous findings that alcohol impairs the amygdala's ability to identify threat signals.
"This suggests that during acute alcohol intoxication, emotional cues that signal threat are not being processed in the brain normally because the amygdala is not responding as it should be," said Phan, according to Psychcentral.
"The amygdala and the prefrontal cortex have a dynamic, interactive relationship," he explained. "If these two areas are uncoupled, as they are during acute alcohol intoxication, then our ability to assess and appropriately respond to the non-verbal message conveyed on the faces of others may be impaired."