Neurogenesis helps break old circuits in the hippocampus
Old memories may get the boot from new brain cells.
A new rodent study shows that newborn neurons destabilize established connections among existing brain cells in the hippocampus, a part of the brain involved in learning and memory. Clearing old memories from the hippocampus makes way for new learning, researchers from Japan suggest in the Nov. 13 Cell.
Other researchers had proposed the idea that neurogenesis, the birth of new neurons, could disrupt existing memories, but the Cell paper is the first to show evidence supporting the idea, says Paul Frankland, a neuroscientist at the Hospital for Sick Children in Toronto.
Scientists have known that memories first form in the hippocampus and are later transferred to long-term storage in other parts of the brain. For some amount of time the memory resides both in the hippocampus and elsewhere in the brain. What’s not been known is how, after a few months or years, the memory is grad