Abnormal EEG synchronisation in heavily drinking students

Objective: In alcoholics, grey and white brain matter is damaged. In addition, functional brain connectivity as measured by EEG coherence is abnormal. We investigated whether heavily drinking students, although drinking for a shorter period than alcoholics, already show differences in functional connectivity compared to light-drinking controls. Methods: EEG was recorded in 11 light and 11 heavy male student drinkers during eyes closed, and eyes closed plus mental rehearsal of pictures. Functional connectivity was assessed with the Synchronisation Likelihood method. Results: Heavily drinking students had more synchronisation in the theta (4–8 Hz) and gamma (30–45 Hz) band than lightly drinking students during eyes closed, both with and without a mental-rehearsal task. Conclusions: Heavy student drinkers have increases in EEG synchronisation that are indicative of changes in hippocampal–neocortical connectivity. Significance: Heavy student drinkers show differences in functional connectivity as compared to their lightly drinking counterparts, even though they have a relatively short drinking history.