Cognitive flexibility during breath alcohol plateau is associated with previous drinking measures

Although the biphasic effects of acute alcohol during ascending and descending Breath Alcohol Concentrations (BrACs) are well described, the plateau period between peak and steadily descending BrACs is generally unrecognized and under-studied by researchers. Naturalistic examinations indicate such periods persist for substantial intervals, with a time frame of onset suggesting BrAC plateaus may co-occur with potentially risky behaviors (e.g., driving). The current pilot study examined neurocognitive performance during this period. Participants were healthy, community-residing moderate drinkers (n = 18). In the first phase of the study, the Digit Symbol Substitution and Trail Making Tasks were administered during BrAC plateau (M = 62 mg/dL). BrACs were negatively correlated with Digit Symbol performance but unrelated to other tasks. In contrast, performance on a derived Trail Making measure of set-shifting was positively associated with the maximum alcohol doses consumed in the preceding 6 months. Phase 2 analyses demonstrated that relationships between previous alcohol experience and cognitive performance were absent among individuals receiving placebo beverages. Taken together, these data suggest a relationship worthy of investigation between previous drinking experiences and cognitive flexibility during the plateau phase.