Is the Lizard Brain a Lie?

I am an animal. I may wear pants and have a Master’s degree and compete in lindy hop championships, yet I am more similar to a monkey or a fish than I was taught to believe.

I came to this realization in my life coach training when I learned that us humans have a “lizard brain” that we share with, well, lizards, and all other animals. Also called the “primitive brain” by coaches, this refers to the part of the brain that humans developed very early on which tells us when to fight, flight, or freeze. It includes the survival instincts that kept us alive and able to develop into the smartphone wielding, moon-visiting species we are today.  

But I know better than to get my science facts from a non-scientist without a grain of salt. So I was dismayed but not surprised when the idea of the “lizard brain” was smashed on an episode of Maintenance Phase, one of my favorite podcasts. They were doing a two-part take-down on Rachel Hollis, which included how none of her advice is backed by science, save for one mention of the Triune Brain Theory, which is where the term “lizard brain” comes from.

Referencing an academic article called Your Brain Is Not an Onion With a Tiny Reptile Inside, the MP hosts are quick to debunk the Triune Brain Theory that the human brain evolved linearly from lesser-evolved species, with one layer growing on top of the other. According to this theory, we have the reptilian “inner core” brain that controls our basic functions, covered by a mammalian limbic system that controls our emotional responses, and us humans developed an outer layer of a cerebral cortex that controls language and reasoning. According to this article, this theory was proved inaccurate even before it was published yet is still widely believed and popularized by books like Carl Sagan’s Pulitzer Prize winning book, The Dragons of Eden.

However, I also know better than to get my science facts from a journalists’ podcast. The MP hosts point out that “If you google this the third result is like, ‘why the triune theory is fake.’” But when one opens and reads those Google search results [i.e., the article referenced above], one learns that we do have common brain parts with other species, such as the amygdala, which activates the fight-or-flight response. Having a prefrontal cortex (which all mammals also have) does not mean we can override our fight-or-flight response. That’s why we might react to an email from our boss the same way we might a rustle in the bushes, but instead of putting up our fists or running away, we think of all the reasons why our boss is a jerk and jump on idealist.org to look for a new job. This is an integral concept to coaching and so helpful personally to understand that I had it tattooed on my arm.

I want to teach how to acknowledge, accept, and sooth ourselves when we are activated by our “lizard brain”. But as a sciencey-gal wanting to share my coaching toolkit with other sciencey-gals, I’m not going to get far with a term associated with theories disproven within the top three Google search result headlines (cause I know my people: we fact check.)  

And while the term “primitive brain” is another simple way to describe how we can be overwhelmed with emotions that feel uncontrollable, it also reinforces the believe that humans are more evolved than other animals. All vertebrates share the same brain regions, they just evolved differently. You can observe incredibly complex reasoning and behavior among species across the board. They exhibit willpower and decision making. They experience emotion. Humans might be unique in how we express our intelligence, but we are not unique in having it.

Acknowledging and respecting animal intelligence is a principle that has led me to a plant-based diet and donating to animal rights organizations. It also motivates me to stop using both lizard brain and primitive brain as shorthand for when our proto-human parts are taking the lead. I don’t want to perpetuate outdated ideas of the brain as an onion or the human as the top of the evolutionary totem-pole. I want to do better.

A quick survey of my life coach colleagues unearthed a plethora of other nicknames for the functions of the amygdala, such as primal brain, survival brain, automatic brain, and preservation brain. Some coaches (mainly the medical doctors who coach other medical doctors) responded that they just use the neuro-anatomical words like midbrain and brain stem, and I get that. “Downstairs brain” might be an easy way to teach children about the fight or flight response, the way some kids learn to call their vagina or penis their “downstairs parts”, but why be cutesy when teaching adults?

Because it’s more than just our fight or flight response. It’s everything animalistic in us, and I don’t mean that in a bad way. I’m talking about all our survival instincts that have kept us alive and procreating for millennia (thank you cerebellum). Our motivational triad which has us seeking pleasure, avoiding pain, and conserving energy so that we can run from that lion (thank you hypothalamus, medulla oblongata, among others). Our desire to people please, be reciprocal, and fit-in with the tribe so we are not left alone to starve (thanks frontal lobes!) Basically, everything that makes us human. And that is all our brain parts, working as a complex system, the same way an octopus or an ant’s brain works as a complex system for them.

At the end of the day, I’m a coach, not a neurobiologist, coaching other non-neurobiologists (to-date; not against it though!). I want a way for me and my clients to understand and make friends with our human nature so that we’re not ignoring or fighting against it. I want a way that is quick and easy to teach and understand, but most importantly, useful. Doing a neuroanatomy 101 lesson is not necessary to teach the role of our brain in our lives. If a client is curious to know exactly which part of the brain is responsible for the behavior we are discussing, I am happy for us to learn together. Whatever helps you have compassion and empathy for the (human) animal inside of you, let’s do it.

Want to learn how your life is impacted by your animal/human nature in subtle and not-so-subtle ways? Or maybe you have other ideas for nicknames for the collective actions of our proto-human brain? Either way, let’s chat!