New Research About Handling Stress

Two recent articles discussing studies of animals in stressful situations shed light on some valuable lessons about the role of stress in people’s lives.

In today’s New York Times Magazine, Gretchen Reynolds writes about an experiment in which two groups of rats ended up reacting differently to the same unpleasant situation. One group of rats exercised regularly for several weeks; the other group didn’t exercise at all. When both types of rats were exposed to stress -- specifically, forced to swim in cold water -- the brains of the exercising rats weren’t affected as negatively as those of the active rats. A related study indicated that, after an injection with chemicals designed to increase their stress level, active rats were less anxious than the idle ones. The studies support the idea that the physical stress of exercise helps the brain better handle emotional stress. But the payoff isn’t immediate. For rats, when it comes to seeing the benefits of exercise, the magic number is apparently between three and six weeks.

Meanwhile, in The Atlantic, David Dobbs writes about the insights of Stephen Suomi, a prominent researcher who has studied the emotional development of rhesus monkeys. Suomi has shown that when monkeys who are genetically handicapped in their ability to process a chemical in their brain known as serotonin -- a risk factor for anxiety and depression -- are raised as babies in poor environments, they grow up to process serotonin less efficiently as adults and are more likely to end up anxious and depressed. But when these genetically-handicapped monkeys are raised in ideal environments, they don’t just grow up to process serotonin efficiently; they do it more efficiently than those monkeys without the initial deficit. Monkeys who thrive despite this genetic weakness may in fact be more likely to prosper than your average monkey.

What does this mean for humans? Suomi’s research with monkeys is relevant to the study of what are sometimes known as “orchid children” -- children who possess gene variants that increase their susceptibility to problems such as depression, anxiety, and attention-deficit hyperactivity disorder. Given a stressful or abusive childhood, these kids are more likely to suffer negative consequences (versus “dandelion kids” who can pretty much thrive anywhere). But the article suggests that if these orchid children are raised in a more favorable environment, then these genetic variants can contribute to enhanced functioning. In short, what has usually been seen only as a liability can, under the right circumstances, be a strength.

As for the stressed-out rat experiments, it adds to a growing body of research indicating that exercise helps not only our physical health, but our mental health as well. As is the case with the rats in these studies, these stress-reducing benefits aren’t immediate. But there’s one important difference between people and the lab rats: Unlike the rats, no scientists are forcing us to exercise. People, unlike rats, need their own motivation. To reap enrichment from an exercise routine, they have to overcome inertia and push themselves to do something they might find unpleasant initially. But if they can stay the course until they start enjoying the returns, it’s worth it.