Our Brains and Decision-Making: Emotional or Rational?

Neuroscientists are now discovering more about the brain and how it processes information and makes decisions. While much remains to be learned, apparently we may not be as rational and in control of our senses as we think we are. The closer scientists look, the clearer it becomes that we are much like our animal ancestors. To understand the brain better, think of it in terms of three layers:

1. reptilian or primitive
2. dog
3. human

Three Brains in One

The reptilian brain consists of the top of the spinal cord and the base of the brain. It consists of those parts we share in common with reptiles and fish. It is responsible for many of our automatic systems for survival, such as breathing and hunger.

Wrapped around these structures is the ancient limbic system which is very similar to the brains of dogs and other mammals. It is the seat of basic emotions such as fear, aggressiveness and contentment.

And encasing these older structures is the modern cortex, the folded gray matter sets us apart from other mammals. Although many animals such as dogs and chimps have cortexes, the human cortex has grown to a huge size. It manages all sorts of things, like hearing and seeing, reasoning, abstract thinking, and our personalities.

We call the prefrontal cortex the ‘executive’ part of the brain because it considers all the input from the brain and makes decisions for goal planning and completion. Or, at least it makes decisions when we let it – when we don’t let our dog brain take over.

Who’s in Charge-Emotions or Reason?

According to scientists who take pictures of the brain during decision-making, the more ancient dog brain is activated as well as the executive brain. There appears to be an ongoing debate between the two brain parts before a decision is made. And, guess what? The dog brain can just as easily win the debate even when logic should win out.

Experiments have shown healthy adults to take a bet even when they are sure to lose, when they can also make their opponent lose. The desire to punish the opponent overrides the desire to win money.

We have dog brains with a human cortex on top. Although our cortexes represent all that is human, logical, rational, and civilized, our animal tendencies are not quiet. They sometimes win the argument over our civilized brain, and make decisions contrary to rationality.

Know Your Brain

We now know that our dog brains win out over our rationality many times, only we come up with logical excuses after the fact. These interactions occur deep within our brains so quickly, we aren’t aware of them.

This was what Malcolm Gladwell was illustrating in his book Blink. We make instant decisions without knowing why, and then make up rational reasons to justify an emotional decision. The picture that emerges from the neuroscience labs is that we ignore our guts at our own peril. We must gain an understanding of how much like other animals we are. Whether we are trusting our partner, buying clothes or a car, or hiring an employee, we must be aware that our dog brains are very busy making an assessment, but in a different way than our human brains. We have to pay attention to this part of ourselves, and realize its impact on our choices.