Gould New Neurons (image) Princeton University Caption A research team based at Princeton University found that physical activity reorganizes the brain so that its response to stress is reduced and anxiety is less likely to interfere with normal brain function. Running produced a large increase in the number of new neurons in the hippocampus -- a brain region shown to regulate anxiety -- of a mouse that ran for six weeks (above). The brown cells are new neurons, which are more numerous in active mice than sedentary mice, and the blue cells are mature neurons. Credit Photo courtesy of the Gould laboratory Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.