Alcohol-Induced Retrograde Facilitation?

Somewhat counterintuitively, alcohol consumption following learning of new information has been shown to enhance performance on a delayed subsequent memory test. This phenomenon has become known as the retrograde facilitation effect (Parker et al., 1981). Although conceptually replicated repeatedly, serious methodological problems are associated with most previous demonstrations of retrograde facilitation. Moreover, two potential explanations have been proposed, the interference and the consolidation hypothesis. So far, empirical evidence for and against both hypotheses is inconclusive (Wixted, 2004). To scrutinize the existence of the effect, we conducted a pre-registered replication that avoided common methodological pitfalls. In addition, we used Küpper-Tetzel and Erdfelder's (2012) multinomial processing tree (MPT) model to disentangle encoding, maintenance, and retrieval contributions to memory performance. With a total sample size of N = 93, we found no evidence for retrograde facilitation in overall cued or free recall of previously presented word pairs. In line with this, MPT analyses also showed no reliable difference in maintenance probabilities. However, MPT analyses revealed a robust alcohol advantage in retrieval. We conclude that alcohol-induced retrograde facilitation might exist and be driven by an underlying retrieval benefit. Future research is needed to investigate potential moderators and mediators of the effect explicitly.