Brain Hemispheres And Personality: A Myth Collapses?

The relationship between personality and the dominance of one of the cerebral hemispheres has been of interest for years. We commonly divide people into two large groups according to their characteristics, and we tend to associate these personal traits with a greater predominance of one of the hemispheres.

Thus, analytical, objective and rational people are said to have a left brain predominance. On the contrary, there is a tendency to believe that those who are spontaneous, dreamy or passionate have a right predominance. But is this true?

In our functioning as human beings, does one of our hemispheres really dominate the other?  Is this the cause of the differences in personality? Throughout this article we will try to shed some light on this complex issue.

Our brain works in a network

We have the belief that our brain resembles a bunch of separate boxes that contain different things. In one is the function of sight, in another memory, in another emotions. According to this idea, our brain would have specialized areas exclusively dedicated to a task. The reality is that our brain is not compartmentalized.

The brain works as a network. Cognitive and emotional functions do not take place in a single location. On the contrary, to carry out any complex function, the intervention of various areas is essential. Our brain works through constant connections between various regions. Therefore, it is not entirely accurate to pigeonhole each capacity into a hemisphere.

However, it is true that each hemisphere has a greater involvement in certain tasks. The right hemisphere is more dominant in visual and spatial tasks, in creative and artistic activities, as well as in spontaneity. On the other hand, the left hemisphere is more involved in logical and objective thinking, abstraction or discipline.

Relationship between cerebral hemispheres and personality

Without losing sight of the fact that both hemispheres are involved in all functions, some correlations have been found between hemispheres and personality:

• Inhibition-Approach : The right prefrontal cortex has been found to be directly related to inhibition responses. On the other hand, the left is associated with approximation responses. In this way, individuals with greater activation of the right prefrontal cortex tend to experience negative emotions with greater intensity. They are also more sensitive to threatening stimuli and therefore more prone to inhibition.
• Field dependence-independence : this concept refers to the greater or lesser facility for a person to perceive reality as a whole, or to be able to isolate the elements. It has been proven that by blocking the right hemisphere of an individual, his field dependence increases.

• Neuroticism : It has been found that people who score high on this personality trait generally activate the right hemisphere more.

Correlation does not imply causality

At first glance, these findings could suggest that our brain structure determines our personality. However, we must bear in mind that correlation does not imply causality. That is to say, that two aspects appear together does not mean that one is the cause of the other. 

It is not correct to say that a person is neurotic because his right hemisphere is more active. Personality formation is a very complex matter that cannot be attributed to the use of either hemisphere. Many genetic and environmental influences coexist in the origin and development of our personal traits.

Does the domain of one of the cerebral hemispheres determine personality?

To answer the questions we asked ourselves at the beginning of the text, we must remember that there is no dominant hemisphere in each individual. A wide variety of brain regions are involved in all the processes that we set in motion. When you speak you are not only using your left hemisphere, just as when you paint you are not only activating the right.

Our brain works as a network of connections. And there is no scientific evidence that, in an individual, one hemisphere has greater government than the other over this network. Therefore, if we want to find the cause of our personality, we will have to investigate our genetic inheritance, as well as the environmental influences that we receive throughout our growth.