It is well known that alcohol acutely impairs ‘retrospective memory’ – our recollection of past events. In everyday life, most forgetting involves failures of ‘prospective memory’ – not remembering to do something we intended to do in the future such as taking particular papers to work or calling a friend that evening. As no study had objectively determined alcohol’s acute effects on prospective memory (PM), we1 administered 0.6g/kg ethanol or a matched placebo to 40 healthy volunteers in a double-blind, independent group study and assessed their performance on a behavioural measure of PM – the ‘Virtual Week’2. Alcohol acutely produced global impairments across the different types of PM tasks (regular, irregular; event-based and time-based). These findings on an ecological measure suggest that 4-5 units of alcohol will compromise PM abilities in everyday life.
In healthy, sober individuals, mentally ‘simulating’ future events enhances PM. So in a second study we set out to see if these acute alcohol-induced impairments could be attenuated by mental simulation. Again using an independent group, double-blind design, 32 healthy volunteers were administered a 0.6g/kg dose of ethanol or matched placebo and assessed PM using the ‘Virtual Week’. We replicated our previous finding that acute alcohol consumption impairs prospective memory for event-based tasks. Future event simulation significantly improved PM performance on these tasks and eliminated the PM deficit caused by acute alcohol consumption. This is the first evidence that future event simulation can overcome alcohol-induced deficits in prospective memory. The next stage in this research is to see whether these findings translate and have any clinical implications for the rehabilitation of chronic alcohol users.
Acknowlegement: we are grateful to the AERC for a small grant which funded the first study.
1. Leitz JR, Morgan CJA, Bisby JA, Rendell PG, Curran HV (2009) Global Impairment of Prospective Memory following Acute Alcohol. Psychopharmacology 205:379-387.
2. Rendell, P. G. & Craik, F. I. M. (2000). Virtual week and actual week: Age-related differences in prospective memory. Applied Cognitive Psychology, 14, 43-62. 22
3. Paraskevaides T, Morgan CJA, Leitz J, Bisby J, Rendell P & Curran HV. Drinking and future thinking: acute effects of alcohol on prospective memory and future simulation. Psychopharmacology, in press.