Neuroscience: The Reptilian Brain

Written by: S. Pradono Suryodiningrat

The reptilian brain is located deep inside the skull. It’s the home of our individual survival instincts and is responsible to deal with life threatening situations not to be technically correct.

The term reptilian brain refers to the erroneous belief that we inherited this part of the brain from our reptilian ancestors, this is incorrect however as amphibians and fish also share this part of the brain we most probably have to go back to our common evolutionary ancestor of all vertebrates.

This part of the brain is sometimes also referred to as the primitive brain. The reptilian brain has three ways of responding to a threat, they are flight, fight, and freeze.

In our lives the reptilian brain still gets activated in situations of life or death even if these are quite few. For example, if you’re crossing the street and a car comes right at you, you will have the same three instinctive reactions.

The first reaction is to jump away or flight. The second reaction is you might consider stopping the car with both your hands like Superman does. However, it might not work. The third reaction is to freeze like a rabbit caught in the spotlight at night, and you’ll just stop moving. Altogether. if you’re lucky the car might miss you.

Our reptilian brain also gets activated when our live is not in danger, but when we are stress. Stress is a defense mechanism to a perceived danger, because humans are probably the only species capable of worrying for something that might never happen anyway. So, when we feel stressed, we actually still use those same three strategies.

The fleeing becomes anxiety. Have you ever felt nervous before a test or when you had to give a presentation? That is the flee stress.

Fighting becomes aggressively. Have you ever come home after a nerve-wracking day at the office and you started shouting at the kids or your partner over something trivial? That is the fight stress in action.

And finally, the free stress becomes helplessness. Have you ever faced an overwhelming task where you didn’t even know where to begin? Only thinking about it made you feel depressed. Well, that is the freeze stress.

To summarize, the reptilian brain structure is responsible for our individual survival instincts. When activated, we feel stress, which can take three forms flight, fight, or freeze or translated in our modern world, anxiety, passivity, or helplessness

S. Pradono Suryodiningrat