Researchers at the Society for Neuroscience meeting in New Orleans (Oct 13-17) presented studies showing how stress, no matter its cause, alters brain circuitry in ways that can have long-term effects on mental health.
Research by Dipesh Chaudhury of the Mount Sinai School of Medicine in New York shows that traumatic events appear to cause depression by derailing the brain’s so-called reward system, which normally causes pleasurable feelings whenever we engage in fun activities like spending time with friends. People who have suffered major stress, such as soldiers returning from combat, often report that they no longer find pleasure in these things.
Mice respond in a similar way to traumatic events, Chaudhury says. And his research shows that this response can be prevented by reducing the activity of certain brain cells involved in the reward system. [Source: NPR, October 15, 2012] A drug causing a similar outcome could eventually be effective in humans.
Stress also causes the release of chemicals that impair the function of the prefrontal cortex, home of higher level thinking. When we experience acute stress, these chemicals–including cortisol and norepinephrine–heighten our reactive tendencies by muting our reflective tendencies, leading to everything from anxiety to aggression to depression.
One of the drugs that appear to reverse these effects is ketamine (I wrote about it recently here), an anesthetic that has the ability to rejuvenate damaged nerve cells in hours, potentially making it a groundbreaking new type of antidepressant. Derivatives of the drug are already in human trials.
The American Psychological Association’s “Stress in America” report provides a useful table, shown below, indicating the effects of stress on your body, your mood, and your behavior.
|Common effects of stress …|
|… On your body||… On your mood||… On your behavior|
The opinions expressed are solely those of the author and do not necessarily reflect the views of Comcast.