THE FIGHT OR FLIGHT RESPONSE
Think back to your ancestors. Not your parents, not even your parent’s parents – think back to your hunter-gatherer ancestors. Let’s say you have a great, great, great, great, great, great grandpa called Org.
Most days, Org hangs out with his son, collects vegetables, rebuilds the family shelter, sharpens his weapons and hunts fish, small birds and animals. One sunny day, Org is playing with his son down at the local watering hole. Even though his body is in a relaxed state, Org’s ears, eyes, nose and other sensory receptors are constantly scanning the environment for potential danger. He notices a rustle in the bushes.
An alert signal travels rapidly to his brain, gearing up his body for a life or death situation. Within a matter of seconds, a pleasant day with his son has now become a frantic fight for survival. A tiger pounces from behind the bushes with razor-sharp teeth, lengthening claws and eyes focused on his potential lunch. Org grabs his son and, within seconds, is frantically trying to get away from a big and very hungry tiger.
Tigers, like most animals that could kill a human, are probably not going to chase Org and his son for days on end. Because of this, Org has become very efficient at activating a fight-or-flight stress response for only a small amount of time. This time, Org and his son were lucky enough to escape. They slowly walk back to their shelter checking for wounds and being thankful for not becoming tiger lunch.
Let’s have a look at the stress response that took place in Org’s body: When Org’s sensory receptors in his eyes and ears detect the presence of the tiger, a signal of DANGER is rapidly sent to a gland in the brain called the hypothalamus. The hypothalamus then delivers a message to the endocrine (hormonal) system to initiate the secretion of hormones. The hormones, primarily the stress hormones adrenaline and cortisol, flood the bloodstream and travel throughout the body to deliver information to his body system and cells that aid in creating the ability to run away or stand and fight.