An Investigation of Episodic Future Thinking, Episodic Foresight, and Prospective Memory in the Context of Acute Alcohol Consumption

Background and Objectives: This research project aimed to investigate the effect of a moderate dose of alcohol on three key forms of prospection, namely episodic future thinking (EFT), episodic foresight, and prospective memory (PM). To date, limited research has directly examined the effect of acute alcohol consumption on prospection, with no studies investigating EFT or episodic foresight in the context of acute alcohol use, and only five studies investigating its effect on PM. Furthermore, very little is known about the cognitive abilities that have been proposed to underpin these forms of prospection, and thus, what may drive any acute alcohol-related impairment in these abilities. Additionally, research investigating the interrelations between the various forms of prospection is scarce, with the majority of empirical studies to date having investigated these abilities in isolation. Three empirical studies were therefore devised to directly investigate the effect of acute alcohol use on EFT, episodic foresight, and PM, as well as their potential cognitive underpinnings, and their interrelations. Specifically, Study 1 aimed to provide the first empirical assessment of EFT following a moderate dose of alcohol, and to examine if any observed difficulties were underpinned by acute alcohol-related difficulties in retrospective episodic memory and/or executive dysfunction. Study 2 aimed to provide the first empirical assessment of episodic foresight following a moderate dose of alcohol, and to examine the extent to which any observed impairment may be contributed to by difficulties in retrospective memory, executive functions, and/or EFT. Study 3 aimed to extend past research by clarifying the nature and magnitude of acute alcohol-related impairment in PM. In addition, Study 3 investigated the cognitive abilities that have been proposed to underpin PM, namely retrospective memory, executive functions, and EFT. Finally, this research project investigated sex differences in each of the key forms of prospection assessed.

Method and Results: A single sample of 124 healthy adult social drinkers aged 18-37 years were recruited and randomly assigned to either the alcohol (n = 61) or placebo (n = 63) condition in a double-blind independent group design. Participants were administered a dose of 0.6g/kg alcohol or a matched placebo drink and completed a comprehensive battery of measures selected to address all research questions of the three studies. Study 1 identified that EFT was impaired by acute alcohol consumption, and that this impairment was underpinned by difficulties engaging in retrospective episodic memory, but not executive functions. Study 2 found that episodic foresight was also impaired by acute alcohol use, and that acute alcohol-related deficits in retrospective memory contributed to episodic foresight performance in the alcohol group. However, executive functions and EFT were not found to underpin episodic foresight performance. Study 3 identified pervasive impairments in PM following acute alcohol consumption, but did not identify any contribution of retrospective memory, executive function, or EFT in PM performance. Finally, the results showed no sex differences in performance on any of the three forms of prospection following acute alcohol consumption.

Conclusions: Overall, this research project provided novel insights into the effect of acute alcohol consumption on cognition and suggests that prospection may be highly sensitive to the adverse effects of acute moderate alcohol consumption. Further research is now needed to clarify the mechanisms through which acute alcohol use induces impairment in these forms of prospection. Future research should also consider replicating this study using a range of doses of alcohol to produce a dose-response curve. These results increase understanding about the difficulties associated with consuming even a moderate dose of alcohol and have significant implications for policy making and the treatment of individuals with an alcohol use disorder.