Effects of moderate doses of alcohol on immediate recall of numbers: some implications for information technology

OBJECTIVE: Moderate doses of alcohol will have detrimental effects on memory functions used in various aspects of human interaction with information technology. The need to deal with multidigit numbers while under alcohol intoxication (e.g., making telephone calls) is a reality of life. To determine these relations, the effects of alcohol on immediate ordered recall were studied in a practical number-dialing task. METHOD: Immediate ordered recall of eight-digit numbers, presented visually or auditorily, was tested in read-and-dial or listen-and-dial forced ordered recall tasks with male subjects (N = 11) under two levels of blood alcohol concentration (BrAC = 0.05% and BrAC = 0.1%) and a no-alcohol placebo control condition (BrAC = 0.0%). RESULTS: With increasing alcohol level, immediate ordered recall of whole numbers (all eight digits correct and in the right order) fell by 9% (visual presentation) and 15% (auditory presentation). No significant interaction effect between alcohol level and digit position in the number was found for visually presented numbers, while a weak, but significant, effect was found for auditorily presented numbers (most prominent at digit positions 5, 6 and 7). This is probably due to the difference in rehearsal opportunities in the two presentation modes. No significant interaction effects between alcohol level and presentation modality were found. CONCLUSIONS: The results, tailored to a practical everyday task of dialing unfamiliar eight-digit telephone numbers, show that even moderate doses of alcohol will affect the performance of an already fragile short-term memory system engaged whenever reproduction of digit strings is required.