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.

“This is suggesting a much more decentralized process,” said Bruno of the findings. He was not involved in the study.“You have lots of different circuits built on top of one another, and they’re all feeding back to one of our most primitive and primordial response systems. They've really shown that stress is controlled by more than the traditional high-level cognitive areas. I think that’s a big deal.”

To explain the implications of this new brain-adrenal “connectome”—as new neural connections are often now being called—requires a look at the mapping process.

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Rabies can be a fantastic tool, in the right hands. Inject it into an organ, and the nerves that feed that organ will take the virus up and carry it backward toward the central nervous system. En route, the virus hijacks the machinery of the nerves in the cell body and dendrites to replicate and grow its numbers, then cross the synapse from a neuron backwards into all of its inputs.

By charting the progress of the virus, scientists can map out the neural connections between an organ and the brain in ways that were previously impossible. In this case, Strick and his team injected the adrenal glands of monkeys.

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.