John Phipps: The Reptile Portion of Our Brain Is to Blame

Maybe it would be more comforting if there were still a few dinosaurs left, on another continent, of course. It’s just the thought that the part of my brain labeled my reptile brain is tough to massage into a compliment. But at the top of our spinal cord, where the human brain developed, sits that lizard legacy.

Mostly it just abides, content to let the later-evolving mammalian sectors run our lives and make decisions of variable quality. However, because sensory information has to traverse those ganglia first, it can trigger a reaction before rational thought. We all have instinctive responses, few enjoyable. Farmers have their own collection.

Instant Triggers
For example, say you walk by grain bins of corn after a strenuous harvest. Two or three complex odor molecules of unmistakable sweetness prompt your lizard brain to electrify your heart and cue panic hormones. A second or two later the higher brain calls up ghastly images of black and blue chunks of moldy corn clogging unloader sumps while the truck fills with colorful dollars of damage dock.

Somewhat related is walking past your trusty combine after a particularly dry, windy day of soybean harvest when you think you might have almost sensed a tiny whiff of smoldering chaff. Frantic hoses and extinguishers nearly convince you have found the ultimate source, but your frontal cortex decides, “No sleep for you tonight.”

While smells are notorious triggers, there are visual stimuli with a similar effect. Any registered letter, for one. Good news does not need a government prod to be read. Likewise, an envelope from the IRS without a window, or any stationery from an unknown law firm. Technology has even given us a new one: the Spinning Ball of Death.

Auditory signals are another vehicle to reptilian overreaction, such as “The cattle are out!” or “There’s water in the basement” or “Eggplant tuna casserole tonight.”

Even our sense of touch can rouse our reptile. A barely felt lurch in a tractor transmission during tillage can snap us to alertness sufficient to examine readouts we haven’t noticed in days. Or emptiness in the wallet slot for your go-to credit card as you start to check out from the grocery.

Stress Point
These instantaneous day-ruiners might have helped our reptilian forerunners survive for millions of years, but not so much when Mr. Asteroid came calling. Now they persist to provide cardiovascular stress checks. Thanks a lot, you stupid pterodactyls. And, oh yeah — DUCK!