What does chronic stress in adolescence mean at the molecular level?

In response to repeated stress, Yan and her colleagues found there was a loss of glutamate receptor expression and function in the prefrontal cortex. That loss resulted in a significant impairment in the ability of the adolescent animals to remember and recognize objects they had previously seen. The same cognitive deficit was not seen in the similarly stressed adults. 

"Because dysfunction in the prefrontal cortex has been implicated in stress-related mental illness, this research identifying how stress affects prefrontal cortical functions will help further unravel how and why mental illnesses occur and how to treat them," says Yan.