Researchers believe they have gained significant insight on how chronic stress clouds the ability to think clearly.

Scientists also believe their lab findings using rats can shed light on how adolescent stress can lead to adult mental illness.

The study, published by Cell Press in the journal Neuron, describes the method by which stress hormones influence the prefrontal cortex (PFC), a brain region that controls high level “executive” functions such as working memory and decision-making.

“Previous work has shown that chronic stress impairs PFC-mediated behaviors, like mental flexibility and attention. However, little is known about the physiological consequences and molecular targets of long-term stress in PFC, especially during the adolescent period when the brain is more sensitive to stressors,” said study author Zhen Yan, Ph.D.

Yan and colleagues examined whether repeated stress had a negative influence on glutamate receptors in juvenile rats. Glutamate signaling plays a critical role in PFC function.

Investigators found that in response to repeated stress, there was a significant loss of glutamate receptors, which resulted in a deficit of PFC-mediated cognitive processes.

The researchers went on to identify the molecular mechanisms that linked stress with the decrease in glutamate receptors and demonstrated that if they blocked these mechanisms, the stress-induced decrease in both glutamate receptors and recognition memory could be prevented.

This could mean that repeated or chronic stress can cause a loss of glutamate receptors and abnormal PFC function.

“Since PFC dysfunction has been implicated in various stress-related mental disorders, delineating molecular mechanisms by which stress affects the PFC should be critical for understanding the role of stress in influencing the disease process,” said Yan.

Source: Cell Press