Exercise good for those brain cells

According to Swedish researchers exercise may stimulate the production of new brain cells in the area of the brain that is important to memory and learning.

The new study conducted by Dr. Astrid Bjornebekk, of the Karolinska Institute, in Stockholm, Sweden, found that both exercise and antidepressants increase the formation of the new brain cells and exercise is a good complement to medicines.

Dr. Bjornebekk says she found, following a series of scientific experiments conducted on rats, that both exercise and antidepressants increase the formation of new cells and she proposes a model to explain how exercise can have an antidepressant effect in mild to moderately severe depression.

Bjornebekk says the studies confirm previous research results, and demonstrates that the effect of antidepressant therapy can be greatly strengthened by external environmental factors.

Other studies have shown that drug abusers have lowered levels of the dopamine D2 receptor in the brain's reward system and it has been suggested that this may be of significance to the depressive symptoms drug abusers often suffer from.

The animal studies show that genetic factors may influence how external environmental factors can regulate levels of the dopamine D2 receptor in the brain and that different individuals may have differing sensitivity to how stress lowers dopamine D2 receptor levels.

This says Dr. Bjornebekk may be significant in explaining why certain individuals develop depression more readily than others.