Posted on Apr 02, 2012, 6 a.m.
Chronic stress may lead to memory problems by interfering with glutamate signaling in the prefrontal cortex, in a lab animal model.
Chronic stress can impair executive functions, such as memory and attention, and has been shown to trigger maladaptive changes associated with stress-related mental disorders. Some previous studies have suggested that stress hormones impair behaviors mediated by the prefrontal cortex, the brain region responsible for executive function. Zhen Yan, from the State University of New York (New York, USA), and colleagues exposed young male rats to repeated stress, which resulted in a significant impairment of the temporal order recognition memory – a cognitive process controlled by the prefrontal cortex, as well as suppression of the glutamate receptor expression pyramidal neurons in that same brain region. The study authors submit that: “Our results suggest that repeated stress dampens [prefrontal cortex] glutamatergic transmission by facilitating glutamate receptor turnover, which causes the detrimental effect on [prefrontal cortex]-dependent cognitive processes.”
Eunice Y. Yuen, Jing Wei, Wenhua Liu, Ping Zhong, Xiangning Li, Zhen Yan. “Repeated Stress Causes Cognitive Impairment by Suppressing Glutamate Receptor Expression and Function in Prefrontal Cortex,” Neuron, 73(5) pp. 962 – 977, 8 March 2012.