Dopamine and Personality

Biology and Personality: Dopamine, D4, and Personality

With hard “core environmentalism” discredited by almost every scientist today, it is then more important than ever to find a biological basis for personality, more importantly, what aspects of personality are inherited? Today we will look at the neurotransmitter dopamine as well as the dopamine D4 receptor, and their link to personality.

There is a wide variety of current research going on finding the link between dopamine and personality, many studies do tend to contradict each other, and so further research is definitely needed. One recurring theme however, that most of today’s research has found is that when dopamine is released into our bodies, our reward system is activated. Personality wise, this means that from the subjects studied, an increase for dopamine in the body lead to more positive feelings. People were more goal oriented, eager, and excited to peruse their desires for things such as money, sex, education. The role dopamine plays in these subjects suggests not that it is an immediate mood booster, rather it drives these individuals to go after their deepest (or shallowest) desires.

Some research has also suggested that dopamine may be the magic extraversion booster, making people more sociable; however there is also other research, which finds no correlation between dopamine and extraversion. Another interesting note about dopamine and the reward system is that it is similar to the reward seeking that cocaine abusers seek, so the question arises: Should injecting dopamine into ones system be a legal alternative to cocaine? Only time will tell.

Low levels of dopamine have been linked with people who have thrill seeking personalities, suggesting they are under aroused and have the need to be stimulated by environmental means. High levels of dopamine are found in Parkinson’s disease patients, this makes sense from the “thrill seeking” perspective as PD patients have the chronic inability to stay still. L-Dopa is a drug that is given to PD patients to alleviate some of their symptoms.

The density of D4 receptors in humans was found to be inversely related to novelty seeking. This finding is similar to the finding on high levels of dopamine and thrill seeking, as someone with many D4 receptors may not need that much external stimulation, A particular study on newborn babies found that the density of D4 receptors in these children was related to the amount of dopamine that binds. The gene for D4 receptors were found on chromosome 11, which also lead to the study that this “thrill seeking” trait is inherited, not that it is a thrill seeking gene, but the low levels of D4 receptors predispose ones personality to go out engaging in stimulating activity.

So what do we get from all of this? Dopamine is clearly still being heavily researched in regards to its link with personality. From what we have seen so far is that dopamine is linked with reward seeking, in a sense it is a motivational tool that drives people to pursue their goals. Low levels of dopamine have been linked with thrill seeking personalities, those of people who may be under stimulated. And the burning question of ethics is that should dopamine be a legal alternative to cocaine abusers? The future of dopamine research is far from over.