Dopamine malfunction

Apomorphine is an agonist at both the and D2 receptors. From the pathological viewpoint, a malfunction of the receptors has been implicated in the negative s)nnptoms of schizophrenia but as there is a close interaction between these receptor types it is difficult to conclude whether the changes seen in schizophrenia are attributable to a primary decrease in receptor function or an increase in D2 receptor function. The function of the D5 receptors is unclear these receptors, though widely distributed in the brain, are only present in a relatively low density in comparison to the other dopamine receptor types. 

Also, a malfunction in the dopamine system has been shown to make it more likely for a person to have a detached personality, which is a characteristic of patients with social anxiety disorder. Serotonin systems are thought to be involved because SSRIs are effective in treating this form of the disorder. Although these systems have been implicated, little is known about how they are malfunctioning to produce the symptoms that characterize this problem. 

All related disorders are attributed to a malfunction of the basal ganglia (which contain a rich array of neurotransmitters and receptors controlling muscular movements) and of the substantia nigra (where dopamine is produced). Dopamine is one of the brain chemicals involved in the control of physical movement, and Parkinsonism is characterized by dopamine depletion. Secondary Parkinsonism, in which symptoms are of a passing nature, is due to temporary dopamine depletion, induced most commonly by antipsychotic drugs. 

The movements of the body also begin to slow down as a result of this malfunction. Drug treatments are designed to increase the level of dopamine or inhibit the release of acetylcholine, which counteracts dopamine. 

The field of psychiatry is predicated on the assumpt-tion that serious mental disorders result from abnormalities in the structure or function of the brain. Although no specific brain anomalies have been identified as the definitive cause of mental illness, the latest neuroscientific studies suggest that imbalances in neurochemicals—also called neurotransmitters— or malfunctions in their transportation from nerve cell to nerve cell might be responsible for the symptoms of mental illness, such as anxiety, depression, hallucinations, and delusions. Neurotransmitters include dopamine, norepinephrine, serotonin, and gamma-amino-butyric acid. Most experts believe that the causes of mental illness stem from a combination of genes (nature) and experiences (nurture). 

Yes, having excess dopamine in the brain doesn t simply make you even happier In fact, overstimulation causes the brain to malfunction, leading to conditions such as schizophrenia, attention deficit hyperactivity disorder (ADHD) and restless leg syndrome. 

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