The only animal with a lizard brain is a lizard

Everybody knows Seth Godin. If not, here is the list of the 21 books he wrote.

He is an excellent marketer. He can tell stories. In the below presentation, he talks about the importance of “shipping regularly”, that is, to release your ideas to the world, even if they are not perfect yet. People are afraid of the feedback of an audience. I agree.

Seth Godin talks about our overly sensitive “lizard brain” part of the brain that can be seen in dogs, chickens, and human, is responsible for holding us back.

He says evolution layered brain parts over brain parts.

First, we grew the lizard brain, then a new one on top, and the neocortex on top of that and - voilà!

Well, not exactly.

He also quotes that chicken are related to T. rex. That seems to actually be correct.

At least more correct than the lizard brain statement, which probably resulted from a famous theory, called the “Triune Brain” theory.

Triune brain theory

The “Triune Brain” is a popular theory developed by Paul McLean, a neuroscientist and physician. Carl Sagan picked it up in his book “The Dragons of Eden”, which won a Pulitzer price. And off the theory went into the world - and probably into the hands of Seth Godin.

The evolutionary theory claims that over time, the brain evolved in layers. Each layer had a distinct function.

The oldest layer, “lizard brain” responsible for survival, then comes the “limbic system” emotional layer, and then the newest layer adds superior functions resulting in us: humans.

It assumes that the brain operates in modular ways, with specific areas being responsible only for specific tasks.

The lizard brain is responsible for breathing and “being horny” (to quote Godin) and then the newest “neocortex” responsible for rational thinking only.

Each brain layer is in constant friction with the “lizard brain” over attention and resources.

Let’s talk about that “lizard brain” of ours for a second.

Evolutionary fun

There is no lizard brain in humans.

Mammals did not evolve from lizards. Humans ancestors were not lizards.

The fact is, we share ancestors, like 350 million-year-old ancestors. Then the lineage split, and lizards, within the group of reptiles, developed their brain on their own.

Because of that, as far as current science is aware, we do not have a lizard brain.

We do share similar structures with other animals. Some of these developed in parallel, others developed together until they diverged.

No lizard brain. No chicken brain. Sorry!

Back to the “Triune Brain”.

Science vs. pop culture model

When I got interested in neuroscience and the workings of the brains, I bought into the idea of the “triune brain” or “brain layers”.

Somehow, it made sense to think of evolutionary development like layers of soil over time. Instead of throwing “old” structures away, evolution built on top or around it, with some improvements to the overall system.

Triune brain is across Youtube, scientific books from renowned authors like Robert Sapolsky and even quoted in research.

It got stuck in pop culture. And until this day, you can find fascinating and emotional discussions like these or these on whether the Triune Brain is debunked or correct or just an oversimplified model of something more complex.

Psychology vs. Neuroscience

Indeed, the theory helps to have simple models to discuss the interconnection between emotions and rational thinking and therefore avoid complex terms and definitions in conversation with people outside the respective fields.

Scientifically, the “Triune Brain” theory is incorrect. We do not have a cake-like layered brain, developed of millions of years by evolution.

We humans thrive on simplified models.

But then it is a fine line then between factual truth and model-like abstraction.

And it becomes difficult when abstracted models are taken as truth or facts.

The learning?

Three-fold:

1. The “Triune Brain” theory used to be a model to describe the evolution of our human brain. Factually, it has been marked as outdated and incorrect. We do not have a “lizard brain”, we do not have a three-layered-cake-brain. This is rubbish.

2. Our brain has evolved into an integrated network. Signals are distributed across various areas. Accordingly, management and leadership, performance and risk management, neurotech and health tech need to avoid isolated approaches catering to only the “IQ” or “EQ”, or isolated brain regions.

3. There is a fine line between abstract models to offer ease-of-understanding and scientific proof. We easily fall into the trap of taking internet-chewable “abstractions” as truth. Asking how and why one more time, might actually be worth the time.

Cheers,

Alex