There are a lot of scientific claims by respected writers that actually don’t hold up under scrutiny. For example, in his book The Biology of Transcendence, Joseph Chilton Pearce makes the eye-opening assertion that 60-65% of the heart’s cells are actually brain neurons. That seemed like a pretty radical claim. When I couldn’t find any evidence to either support it or deny it, I contacted Andrew Armour, M.D., editor of the journal Neurocardiology and asked him. What he told me is that it’s true that the heart contains brain cells, but they only number about 20,000 or so. It was his learned opinion that adding more (or substracting), would significantly interfere with the smooth function of the heart. So-called heart-felt emotions, he further added, are primarily a neurophysiological effect that is mostly centered in the brain (even though heart-felt emotions do have somatic components. It’s virtually impossible to be heart-felt when our limbic system is highjacked, for example. Heart-felt emotions appear to require significant brainstorms of dopamine and oxytocin, rather than cortisol and noradrenaline).
So, recognizing that all scientific claims can’t simply be taken at face value – the world and we are extraordinarily complex – here’s the latest brain fact that sent me cartwheeling to the library stacks (libraries still have stacks, believe it or not): 80% of the brain’s neurons are contained in a relatively small structure at the base of the skull called … the cerebellum, Latin for “the little brain.” 80%! If I’m on the original brain design team and I agree to allocate 80 percent of the brain’s resources to one group of functions, I probably think it’s a pretty important collection (Note: 80% of the brain’s connections are not found in the cerebellum).
These cells (pur-KIN-gee) have massive branching arbors and are primarily responsible for – guess what? – body movement coordination and motor learning – essentially learning to use skeletal muscles effectively. Like how to simultaneously walk and chew gum, or sprint with grace, or dance and not look like a dork. If you can’t do any of these things: 1. you can mostly fault your cerebellum; and 2. you have virtually unlimited capacity to actually learn how to do those things and many more with grace beyond measure! Spend a season on Dancing with the Stars. Regularly moving our body would appear to be REALLY important to the brain. A great way to spend a good part of every day?
And One More Thing, or Two
But the cerebellum is also radically wired into the limbic system. It’s got an undeniable reptilian ancestry. That suggests it plays an active role in the fight-flight-freeze response. Which further suggests it’s an active player in the formulation of and the retention of traumatic memories – perhaps even how we retain traumatic “body memories.”
But here’s something I find most interesting about Purkinje. He also traced fibers in the heart, where they are chiefly responsible for the pump action that results in … a heartbeat. I wonder what secret signals that life-long pulsation sends to its Purkinje brethren hanging out in my cerebellum when I’m 99% not paying attention?