Neurocognitive and mood effects of alcohol in a naturalistic setting.

Objective: The current pilot study aimed to assess the effects of drinking alcohol in a naturalistic setting on aspects of performance.

Methods: Thirty individuals were approached and tested individually in a university campus bar. They provided details regarding alcoholic drinks consumption. Each was breathalysed before and after completion of a computerised test battery administered on a handheld device. The battery consisted of visual analogue mood scales, a series of alcohol-sensitive psychomotor and cognitive tests.

Results: There were highly significant correlations between measured blood alcohol concentrations, estimated units of alcohol consumed and scores on a 'sober-drunk' VAS (p < 0.001 in all cases). For performance, there was a characteristic alcohol-associated shift in the speed/accuracy trade-off (SATO), which was reflected as significantly more errors with less effect on speed across several measures (including maze performance and Serial Sevens). Individuals who were more intoxicated were also significantly less alert.

Conclusions: The data suggest that controlled laboratory tests into the effects of alcohol intoxication may have ecological validity, with SATO shifts amongst the characteristic impairments seen in both controlled and naturalistic settings.