Neurogenesis in the Adult Brain

National Institute Of Mental Health

Investigators

Linked publications, trials & patents

Abstract

This project focuses on understanding the function of adult neurogenesis in the hippocampal region of the brain. We are interested in understanding how experiences, including positive and stressful experiences, regulate adult neurogenesis and how the new neurons alter behavior in different situations. We study the regulation and function of adult neurogenesis in rats and mice, which show continued production of new neurons throughout adulthood similar to that in primates, including humans. The hippocampus is thought to play an important role in spatial learning and memory, but many spatial tests for rodents are also stressful, making it difficult to determine whether any changes in behavior are due to effects on spatial abilities or stress response. We have focused recently on testing the effects of inhibiting adult neurogenesis in non-stressful tasks. In a rewarded operant task, in which rats have to choose between levers with different payout probabilities, rats lacking neurogenesis consistently do better than control rats with a normal complement of new neurons. However, in exploratory tests, rats without neurogenesis often show higher levels of caution, or anxiety-like behavior, and show greater behavioral change in response to stress. These effects are exacerbated in rats that stop making new granule neurons before they reach adulthood.