What is dopamine, and what role does it play in psychiatric disorders?
Dopamine is a neurotransmitter that plays an important role in carrying out many brain functions in humans and animals. Like other neurotransmitter, dopamine is a chemical that carries out communication and interaction between nerve cells.
What is dopamine?
Dopamine is more densely found in certain centres of the brain and influences the activities in that area. One of these centres is an area in the midbrain referred to as ‘substantia nigra’ which plays a role in the proper execution of body movement in humans. Damage to these and the surrounding nerve cells results in a movement disorder in which the movements of the body slow down, often accompanied by involuntary tremors. The most common of this type of disease is Parkinson’s disease. Treatment of Parkinson’s disease involves replacement of the missing neurotransmitter dopamine in the brain centres where it is absent because of nerve damage.
Dopamine’s role in psychiatric disorders
Dopamine plays an important role in psychiatric disorders. Dopamine to a large extent manages the interaction between the brain centre called ‘prefrontal cortex’, which is located in the front part of the brain and directs the intentional and goal orientated behaviour of the person, and the brain centres that are located further back.
Dopamine’s relationship with behaviour and habits
It is believed that dopamine is closely related to the tendency of the person to continue with a particular behaviour or habit (with the brain’s reward mechanism), and that as a result it plays an important role in the formation of the mechanism we see in alcohol dependency, gambling addition or internet-computer addiction.
Psychiatric disorders in which dopamine plays an important role
Another group of psychiatric disorders in which dopamine plays an important role, are psychotic disorders where the person’s ability to assess reality is severely affected. The condition is accompanied by delusions (beliefs that are clearly wrong but cannot be changed) and hallucinations.
It is proven that in these disorders the dopamine system functions excessively. In fact, anti-dopaminergic drugs (drugs that reduce the efficiency of dopamine) are used in the treatment of such psychiatric disorders so that the normal functions of the dopamine system can be maintained.