THE BIOLOGICAL BASIS OF STRESS – THE UPSIDE
Although it is true that our beliefs shape us there are some biological facts that we also have to take into account. From an evolutionary perspective we have survived as a species because we learned to adapt to the need to defend ourselves in a hostile and dangerous world. In prehistoric times, early man had only the most rudimentary weapons with which to hunt and protect himself against wild animals and other dangers. He had a more developed brain than any other animal which enabled him to think and conceptualize but it also needed to provide him with ways to deal with forces physically much stronger than him. One of the most important mechanisms that evolved, one that we share with many other animals, is known as the Fight or Flight reaction. You can see this in a more rudimentary form when you startle an animal. It either immediately flees or if you are unlucky it tries to attacks you. It is this reaction that is triggered when we are faced with a life threatening situation. The body is put in a state of high alert. We experience the “rush” as adrenalin is pumped into our bodies and our heart starts beating harder. Many other reactions occur that focus all our resources on the need to deal with surviving the threat we face. The end result is that we are able to be at the peak of our physical abilities. We somehow have the energy to run faster than we could have thought possible and have the strength to fight we did not know was in us. The ability to sustain this heightened state is limited because we are drawing on our own reserves. As these reserves are used up we experience exhaustion.
These automatic responses do not rely on higher thinking processes to be activated. They are fast, immediate and focus all our awareness on the danger in front of us. On the downside their intense focus also makes us blind to any thing else that is going on in the environment. They also temporarily override our higher thinking. In redirecting our blood supply to areas of the body needed for our defense they take it from other vital functions like digestion and our immune system. As long as this is a short lived reaction no harm is done. The extra energy made available helps us deal with potentially threatening situations.