Effects of an acute dose of palm alcohol on normal brain functioning: an auditory, event-related-potential study

The effects of an acute and high dose of palm alcohol (900 mg/kg bodyweight) on brain functioning were investigated in 10 healthy, non-alcoholic men. Each was given randomly-interspaced, paired, frequent standard (80%) and rare target auditory stimuli and asked to detect and signal the target tone by pressing a push button. These brain function tests were carried out before (control) and 1 and 4 h after the subjects began drinking the alcohol. During each experimental session, late, event-related-potential (ERP) components were recorded at the central midline scalp location (Cz). At both times after alcoholization, contingent negative variations and late auditory ERP were lower than those recorded during the control session. Maximal amplitude reduction for N1 and P3 waves was seen 240 min after ingesting alcohol. Reaction times were not significantly longer than those recorded pre-alcoholization but performances were lower at both times post-alcoholization. The results are consistent with the ERP changes reported in subjects under acute ethanol intoxication but they are more pronounced and probably reflect a momentary disruption of central processes rather than sensory impairment at the peripheral level.