Decreases in recollective experience following acute alcohol: a dose-response study

Acute alcohol intoxication induces a selective impairment of recognition memory associated with conscious recollection whilst recognition based on familiarity is left intact.

We aimed to further elucidate the acute effects of alcohol on recognition memory by assessing three different doses of alcohol and examining the way in which this affected the recollection and familiarity components of recognition memory in comparison to a placebo group.

A double-blind independent design was used, and participants received either alcohol (0.4, 0.6 or 0.8 g/kg) or a placebo drink. Participants encoded word pairs with depth of processing manipulated under generate and read conditions. Recognition memory was assessed and recollective awareness was examined through use of the remember-know procedure.

Alcohol produced a dose-dependent reduction in recognition memory associated with recollection, evidenced by decreases in the number of correctly recognised items with 'remember' responses compared to placebo. Recognition based on a familiarity, evidenced by 'know' responses, showed no differences between groups or pattern of reduction compared to the placebo group. However, a negative correlation was found between recognition based on familiarity and levels of intoxication.

Alcohol-induced impairments in recognition memory occur in a dose-dependent manner, specifically driven by reductions in recognition associated with conscious awareness.