Dream, memory and Freud's reconciliation with the brain

Abstract

What is the function of dreaming? The vast contribution on dreams made by Freud and Jung has been largely ignored by science, which harshly criticized their approach for the lack of a quantitative method and of testable hypotheses. Here I review a series of experimental results that corroborate two important psychoanalytical insights regarding dreams: 1) that dreams often contain a "day residue" of the preceding waking experience, and 2) that such "residue" includes cognitive and mnemonic activities, therefore leading to a facilitation of learning. In particular, recent data suggests that dreams may play an essential role in memory consolidation, allowing recently-acquired memories to exit the hippocampus and settle in the neocortex. Taken together, these results call for a comprehensive scientific reassessment of the psychoanalytical legacy.