A new study published in the Journal of Neuroscience sheds light on the neural mechanisms that may explain why people with alcohol dependence often prefer alcohol over other rewards.

Researchers from Amsterdam University Medical Center, led by Nathan Marchant, used rat models to investigate how activity in a specific brain region influences the choice between alcohol and social interaction.

The rats were trained to press levers to receive two types of rewards: alcohol or the opportunity to interact with other rats. The results showed a clear preference for alcohol. At the same time, the anterior insular cortex — a brain region involved in planning and decision-making — was more active during alcohol-related actions than during choices involving social interaction. A particularly strong increase in activity was observed immediately before a decision was made.

A mathematical model of the data revealed that activity in the anterior insular cortex correlated with the speed at which rats chose alcohol once a preference had been established. This suggests that this brain region may encode a bias in the decision-making process, reinforcing the selection of alcohol over other rewards.

According to Nathan Marchant, such models help break down decision-making into variables that explain animal behavior and may also be applicable to humans with alcohol dependence.

This is especially important for understanding maladaptive alcohol-related choices characteristic of addiction and could potentially form the basis for developing new therapeutic strategies.

Overall, the study indicates that neural signals in the anterior insular cortex play a key role in how alcohol preferences are formed and opens new avenues for more precise understanding and treatment of alcohol addiction in humans.