The long-held view that no new neurons form in the brain during adulthood has been proven incorrect. In fact, one brain region found to sprout new neurons throughout life is the hippocampus, the area linked to learning and memory.

Does this area grow new neurons in response to mental stimulation? The answer to this question is not yet known. However, it has been shown in studies with mice that those reared in a stimulating environment, containing toys, exercise apparatus, and opportunities for social interaction, generated new neurons at a greater rate than litter mates raised in standard cages. The mice with more cells also performed better on learning and memory tests involving negotiating mazes.

If these findings are also true for humans, then staying mentally and physically active would translate into improved memory and learning. However, the direct correlation between mental and physical activity and growth of new neurons in humans has not yet been shown.