Alcohol intoxication alters cognitive skills mediated by frontal and temporal brain regions

• Moderate and high doses of alcohol impair frontally- and temporally-mediated cognitive skills.
• Alcohol intoxication impairs sustained attention in males but not females.
• The effects of alcohol on sustained attention and verbal memory follow a U shape.
• Greatest impairment in attention and memory occurs at moderate doses of alcohol.
• Expectancy effects of alcohol did not impair cognitive performance.

Alcohol intoxication affects frontal and temporal brain areas and may functionally impair cognitive processes mediated by these regions. This study examined this hypothesis by testing the effects of alcohol on sustained attention, impulsivity, and verbal memory. Sober and placebo control groups were used to distinguish pharmacological from expectancy effects of alcohol. One hundred nine university students were assigned to an alcohol (low, medium, or high dose), placebo or sober group. Moderate and high doses of alcohol impaired all cognitive measures. A gender effect was revealed in that alcohol impaired sustained attention in males, but not females. Both sustained attention and verbal memory exhibited a U-shaped pattern, in that the medium-dose alcohol group showed the greatest impairment. This study adds to knowledge about the effects of alcohol intoxication on frontally- and temporally-mediated cognitive function. These findings have specific relevance for heavy-drinking undergraduate populations, particularly in light of the fact that repeated alcohol administration produces persistent changes in brain neurocircuitry.