Researchers at Columbia University Medical Center provide the first evidence that the number of neural stem cells of the hippocampus, the region of the brain responsible for memory, learning, and emotion, may not be constant, but can be altered by varying environmental conditions. Comparing the hippocampi of mice exposed to a stimulating environment or an isolated, stressful one, they found that the hippocampal stem cells of those held in isolation generated more neural stem cells than in the stimulated mice, whose neural stem cells differentiated to produce neurons only.
The researchers hypothesize that during times of stress or deprivation, the brain readies itself by stockpiling neural stem cells so that it can meet the demands of a more stimulating environment, which is known to fuel the production of more neurons. The results, published online in Neuron on June 9, demonstrate a new form of neural plasticity. Further research into the environmental factors that stimulate neuron and neural stem cell production, and the mechanisms that lead to such production, could inform new treatment options for people with neurodegenerative diseases, such as Alzheimer’s and Parkinson’s.