Rapid Cortical Plasticity Supports Long-Term Memory Formation

Abstract

The standard systems consolidation account posits that recently formed memories are initially dependent on the hippocampus and only gradually become instantiated in neocortical networks over a period of weeks to years. However, recent animal and human research has identified rapid formation of cortical engrams at the time of learning that can support hippocampal-independent memories within hours or days. Conditions that promote rapid cortical learning include relatedness to prior knowledge, activation of knowledge in the service of action selection or active discovery, and repeated retrieval. Here, we propose that cortical hubs can support rapid learning through synchronous activation of sensorimotor representational cortices. Candidate neurobiological mechanisms include unmasking of latent synaptic connections and rapid synaptic remodeling driven by disinhibitory processes.

Keywords: cortical learning; engrams; hippocampus; long-term memory.