It’s long been known that experiencing control over a stressor immunizes a rat from developing a depression-like syndrome when it later encounters stressors that it can’t control.
Now, scientists funded by the National Institute of Mental Health (NIMH), part of the National Institutes of Health (NIH), have unraveled the workings of the brain circuitry that inoculates against such hard knocks ? the circuitry of resilience.
Control not only activated the brain’s executive hub, the prefrontal cortex, but also altered it so that it later activated even when the stressor was not controllable. This activation turned off mood-regulating cells in the brainstem’s alarm center. The immunizing effect was so powerful that even a week later, when confronted with an uncontrollable stressor, the cells behaved as if the stressor was controllable and the rat was protected.
“It’s as if the original experience with control leads the animal to later have the illusion of control even when it’s absent, thereby producing resilience in the face of challenge,” explained NIMH grantee Steven Maier, Ph.D., University of Colorado. “The prefrontal cortex is necessary for processing information about the controllability of stressors as well as applying this information to regulate responses to subsequent stressors.”