Depression caused by difficult and stressful psychosocial experiences can be alleviated thanks to interesting and stimulating activities, argue US scientists in the pages of Molecular Psychiatry. In their opinion, behavioral therapies that stimulate the formation of new neurons in the brain are a good way to treat the effects of stress.
Chronic stress inhibits the formation and survival of newly formed neurons in the brain, adversely affecting the brain’s ability to adapt to environmental changes. Not being able to notice and adapt to changing situations are symptoms of depression and post-traumatic stress disorder. The factor stimulating neurogenesis, i.e. the formation of new nerve cells, is the enrichment of the environment, enabling the performance of new, stimulating activities.
Michael Lehmann and colleagues at the National Institute of Mental Health in Bethesda set out to investigate the relationship between neurogenesis and the ability to cope with stress in mice. Scientists studied two groups of animals – ordinary mice and rodents genetically modified so that they did not develop new neurons in adulthood.
In order to induce stress, both groups of mice were exposed several times to a group of dominant, large and aggressive male mice. Then, the test mice were placed in cages equipped with running wheels, tunnels and platforms.
Scientists observed that in normal mice, enrichment of the environment abolished symptoms of depression, and in transgenic animals with blocked neurogenesis, it did not. According to the authors, this proves the important role of neurogenesis in behavioral therapy. (PAP)