Scientists now believe that the key factor in transferring information from short-term to long-term memory is a process called memory consolidation. This process involves the strengthening and stabilization of neural connections formed during initial encoding of information. Memory consolidation occurs during sleep, particularly during the deep sleep stage known as slow-wave sleep. During this time, memories are replayed and reactivated, which helps to reinforce connections and integrate new information into the existing network of long-term memories.
