Teen Stress Linked to Adult Mental Illnesses like Major Depression and Schizophrenia

Could teen angst cause adult schizophrenia, major depression and other serious mental illnesses?

Well if people are anything like mice (and apparently we are) for people already predisposed to mental illness, experiencing stress while a teen greatly increases the odds of developing full-blown mental illness as an adult.

The Experiment

John Hopkins Medical School researchers started off with a group of mice that had a genetic predisposition to serious mental illness.

• Half of the mice served as a control group, and were raised through adolescence as normal
• The other half served as the experimental group. During adolescence, these mice were placed in isolation for 3 weeks (Inducing stress)

The Results

• The mice that were stressed during adolescence were far more likely to exhibit symptoms of mental illness in adulthood than the mice that were raised as normal to adulthood.
• When the researchers examined the brains of the experimental mice they found that mice exposed to stress during adolescence had higher levels of the stress hormone cortisol and lower levels of the neurotransmitter dopamine in areas of the brain related to higher order brain function, like emotional regulation and thinking.
• To see if it was cortisol that was causing the reduction in dopamine, the researchers then chemically blocked cortisol transmission. This caused dopamine levels to normalize.

The Significance

Commenting on the significance of the research, the study authors point out that:

1. Gaining an understanding of the biological causes of elevated cortisol levels in the brain may help in the development of medications to control stress hormone levels and treat certain mental illnesses.
2. To prevent mental illness, we need to do a better job of protecting people already predisposed to mental illness from stress during adolescence, for example, by protecting children growing up in families with mental illness from experiencing neglect.

Read the full study results in Science.