A new anatomical understanding of how movement controls the body’s stress response system
James Hamblin writes in the Atlantic:
Elite tennis players have an uncanny ability to clear their heads after making errors. They constantly move on and start fresh for the next point. They can’t afford to dwell on mistakes.
Peter Strick is not a professional tennis player. He’s a distinguished professor and chair of the department of neurobiology at the University of Pittsburgh Brain Institute. He’s the sort of person to dwell on mistakes, however small.
“My kids would tell me, dad, you ought to take up pilates. Do some yoga,” he said. “But I’d say, as far as I’m concerned, there’s no scientific evidence that this is going to help me.”
Still, the meticulous skeptic espoused more of a tennis approach to dealing with stressful situations: Just teach yourself to move on. Of course there is evidence that ties practicing yoga to good health, but not the sort that convinced Strick. Studies show correlations between the two, but he needed a physiological mechanism to explain the relationship. Vague conjecture that yoga “decreases stress” wasn’t sufficient. How? Simply by distracting the mind?
The stress response in humans is facilitated by the adrenal glands, which sit on top of our kidneys and spit adrenaline into our blood whenever we’re in need of fight or flight. That stress response is crucial in dire circumstances. But little of modern life truly requires it (especially among academic scientists). Most of the time, our stress responses are operating as a sort of background hum, keeping us on edge. Turn that off, and we relax.
For a long time, it has been understood that the adrenal glands were turned on and off by a couple discrete pathways coming from the brain. “Folks said there was one particular cortical area, perhaps two, that controlled the adrenal medulla,” Strick explained.
Randy Bruno, an associate professor of neuroscience at Columbia University, further explained that “the way people usually think about the cortex, it’s very hierarchical.” That is, perceptions come in from the world and get sent from one part of the brain to the next, to the next, to the next. They go all the way up the chain of command to the frontal cortex. That sends some signals down to create motor actions.
If stress is controlled by these few cortical areas—the part of the brain that deals in high-level executive functioning, our beliefs and existential understandings of ourselves—why would any sort of body movement play a part in decreasing stress?
Now Strick seems to have solved his own problem. In the journal Proceedings of the National Academy of Sciences, the Pittsburgh neuroscientists showed that they have discovered a discrete, elaborate network in the cerebral cortex that controls the adrenal medulla. It seems that the connections between the brain and the adrenal medulla are much more elaborate than previously understood. Complex networks throughout the primary sensory and motor cortices are tied directly to our stress responses.
That discovery transformed Stricks’ understanding of how bodily movements influence our health. He’s starting Pilates. . .