Alcohol can cause a striking mental change in drinkers.
People who drink alcohol excessively show more extensive dysfunction in their brains than previously thought. This is indicated by the results of a new study conducted by the team of Theodora Duka and Charlotte Rae, from the School of Psychology at the University of Sussex, United Kingdom.
The main finding of this research is that brains of those who drink a lot of alcohol have to work harder than those of normal people to feel empathy for other people who suffer.
The research was done with 71 study subjects (from France and the UK). Brain activity of these people was observed by functional magnetic resonance imaging scanners while they were performing a task of assessing the pain suffered by others. Half of these individuals were classified as heavy alcohol users and half were not. The drinkers were sober during the experiments.
Excessive alcohol consumption was defined as the consumption of more than 60 grams of pure alcohol (equivalent to about three-quarters of a bottle of wine) on at least one occasion in the last 30 days.
In the task, participants were shown an image of an injured limb, and asked to imagine that the body part was someone else's, and to state how much pain was associated with the image. Participants who drank alcohol excessively had to work harder than participants without that problem when they tried to adopt the perspective of another person experiencing the pain; they took longer to respond and the scans revealed that their brains had to work harder (use more neural resources) to appreciate the intensity with which another person would feel the pain.
"Our results are pretty amazing," Rae confesses. "Our data show that consumers of excessive amounts of alcohol need to work harder to empathize with other people in pain. They need to use more resources in terms of higher brain activity than moderate drinkers. What this means in everyday life is that people who drink excessive amounts of alcohol may have difficulty perceiving the pain of others. It's not that they feel less empathy, but that they need to allocate more brain resources in order to do so. However, under certain circumstances, when those resources are limited, those drinkers may have difficulty in reacting with empathy to others," he concludes.