Welcome to my world!! I guess I’m so used to seeing the connection between stress, immunity, and the physical body, that I’m surprised that it’s still in question.
This is the original PNAS paper.
Some excerpts from the interview:
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…
The motor areas in the brain connect to the adrenal glands. In the primary motor cortex of the brain, there’s a map of the human body—areas that correspond to the face, arm, and leg area, as well as a region that controls the axial body muscles (known to many people now as “the core”).
The Pitt team didn’t think the primary motor cortex would control the adrenal medulla at all. But there are a whole lot of neurons there that do. And when you look at where those neurons are located, most are in the axial muscle part of that cortex.
“Something about axial control has an impact on stress responses,” Strick reasons. “There’s all this evidence that core strengthening has an impact on stress. And when you see somebody that’s depressed or stressed out, you notice changes in their posture. When you stand up straight, it has an effect on how you project yourself and how you feel. Well, lo and behold, core muscles have an impact on stress. And I suspect that if you activate core muscles inappropriately with poor posture, that’s going to have an impact on stress.”
With this come implications for what’s currently known as “psychosomatic illness”—how the mind has an impact over organ functions. The name tends to have a bad connotation. The notion that this mind-body connection isn’t really real; that psychosomatic illnesses are “all in your head.” Elaborate connections like this would explain that, yes, it is all in your head. The fact that cortical areas in the brain that have multi-synaptic connections that control organ function could strip the negative connotations.