Memory allocation and integration in rodents and humans

In rodents, recent studies indicate that levels of neuronal excitability dictate which cell populations encode a memory for a particular event (i.e. memory allocation), and whether memories for multiple events become linked. In human subjects, imaging methods now allow for detection of brain responses to specific events, and therefore make it possible to address whether analogous processes are engaged. Similar to rodents, these studies reveal that neural engagement prior to learning influences encoding in humans. Furthermore, they provide evidence that events that share content, or occur close together in time, become linked during learning or during later 'offline' processing (i.e. memory integration). These concepts of memory allocation and memory integration provide a common mechanistic framework for considering how knowledge emerges in rodents and humans.