Mechanisms of sleep-dependent memory consolidation in human infants

Gomez, R.

The University of Arizona

Abstraction is a crucial form of learning involving retention of key aspects of experience that enable generalization to new information. This ability is crucial for young children who must apply new knowledge to similar but not identical instances to those encountered during learning. Our earlier work showed that infants who slept between training and test retained knowledge of a pattern they applied to highly similar test stimuli (Gómez et al., 2006). Here we ask whether sleep permits detection of the pattern in test stimuli that were made highly dissimilar by changing vocabulary between learning and test while retaining the underlying pattern. Two studies testing two developmental populations (12- and 18-month-olds) show successful detection of a pattern in highly dissimilar stimuli after sleep but not after wake, demonstrating portability of the knowledge abstracted with sleep and raising questions about the mechanisms involved. While work in adults implicates a role for active systems consolidation in the abstraction of an underlying pattern (Durrant, et al., 2012), brain development in the ages of the infants we tested is inconsistent with this hypothesis, leading us to favor an alternate explanation for the locus of the sleep-dependent effects in our young learners.