Neurogenesis (“birth of neurons”) of neurons in the hippocampus can occur throughout the life of mammals, including humans.
A new study shows that adult born neurons (ABN) appear to be crucial to the formation and consolidation of new memories in the hippocampus.
The most recent research by Yanagisawa and colleagues suggests that during REM sleep, ABNs undergo synaptic changes that increase their plasticity and enable more robust memory consolidation. Additionally, the unique brain wave oscillations that occur during REM sleep may facilitate synchronization between specific adult-born neurons that are key to memory consolidation. (How Dreaming Helps the Brain Consolidate Memories)
The study can be found here: Sparse Activity of Hippocampal Adult-Born Neurons during REM Sleep Is Necessary for Memory Consolidation.