Alcohol Reduces Cross-Frequency Theta-Phase Gamma-Amplitude Coupling in Resting Electroencephalography

BackgroundThe electrophysiological inhibitory mechanism of cognitive control for alcohol remains largely unknown. The purpose of the study was to compare electroencephalogram (EEG) power spectra and cross-frequency phase-amplitude coupling (CFPAC) at rest and during a simple subtraction task after acute alcohol ingestion. MethodsTwenty-one healthy subjects participated in this study. Two experiments were performed 1week apart, and the order of the experiments was randomly assigned to each subject. During the experiments, each subject was provided with orange juice containing alcohol or orange juice only. We recorded EEG activity and analyzed power spectra and CFPAC data. ResultsThe results showed prominent theta-phase gamma-amplitude coupling at the frontal and parietal electrodes at rest. This effect was significantly reduced after alcohol ingestion. ConclusionsOur findings suggest that theta-phase gamma-amplitude coupling is deficiently synchronized at rest after alcohol ingestion. Therefore, cross-frequency coupling could be a useful tool for studying the effects of alcohol on the brain and investigating alcohol addiction.