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Rabies moves at a predictable rate, replicating every eight to 10 hours, moving rapidly through chains of neurons and revealing a network. The researchers could allow the virus to move up the nervous system and reach the brain but could sacrifice the monkey before it showed any symptoms of infection.

When the virus has had enough time to travel a predictable distance, the researchers anesthetize the animal, wash out its blood, perfuse the central nervous system with fixatives, and use antibodies to detect where the virus has spread. The kills were timed to various stages to create a map. By the time you’ve gone through several sets of synapses that mapping is an enormous task. There’s an exponential increase in the number of neurons.

the researchers were astounded at what they saw. 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”).

“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.”

“These neural pathways might explain our intuitive sense for why there are many different strategies for coping with stress,” said Bruno. “I like the examples they give in the paper—that maybe this is why yoga and pilates are so successful. But there are lots of other things where people talk about mental imagery and all sorts of other ways that people deal with stress. I think having so many neural pathways having direct lines to the stress control system, that’s really interesting.”

Bruno specializes more in sensory neuroscience, so he read a more into the findings in the primary somatosensory cortex. Some of these tactile areas in the brain seem to be providing as much input to the adrenal medulla as the cortical areas. “To me that's really new and interesting,” said Bruno. “It might explain why certain sensations we find very relaxing or stressful.”

“It's not clear to me—from our work, and from their work—that what we call motor cortex is really motor cortex,” he said. “Maybe the primary sensory cortex is doing something more than we thought. When I see results like these, I go, hm, maybe these areas aren’t so simple.”

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

As he put it, “How we move, think, and feel have an impact on the stress response through real neural connections.”