Researchers have shed light on the process that allows the brain to remember new memories while preserving old ones.
A study at the RIKEN-MIT Centre for Neural Circuit Genetics discovered that neurons in a brain region called the dentate gyrus have distinct roles in memory function.
Their formation depends on whether the neural stem cells that create them are of an old or young age.
The research could have a dramatic impact for treating conditions such as dementia that are characterised by memory disorders.
According to researchers, the study also indicates that an imbalance between young and old neurons could disrupt normal brain functioning during post-traumatic stress disorder and the ageing process.
Susumu Tonegawa, senior author of the study and 1987 Nobel Laureate, explained: "In animals, traumatic experiences and ageing often lead to decline of the birth of new neurons in the dentate gyrus.
"In humans, recent studies found dentate gyrus dysfunction and related memory impairments during normal ageing."
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