Dopamine Hypothesis of Schizophrenia

Professor Jeffrey Lieberman discusses the dopamine hypothesis, the predominant neurochemical theory of schizophrenia.

Professor Jeffrey Lieberman discusses the dopamine hypothesis, the predominant neurochemical theory of schizophrenia.

There are several neurochemical hypotheses as to why schizophrenia occurs. The first of these was the dopamine hypothesis. Dopamine is what's called a neurotransmitter, meaning that it’s a chemical that allows two neurons in the brains to communicate, produces a bridge across the synapse between two cells and allows continuation of the nerve impulse to progress. So, the dopamine hypothesis of schizophrenia basically says that the symptoms of schizophrenia, principally the hallucinations, the delusions, the psychosis is the result of too much dopamine being active in the brain, being secreted into the synapses within a certain neural circuit. And as a result of this, it produces this over-stimulation of the cells and these symptoms. One of the reasons that we know this is the case is because often times, people who have not had the illness will experiment with drugs like cocaine, or amphetamine, or methamphetamine, drugs that stimulate the release of dopamine in the brain. Their experimenting, taking these medications will precipitate the onset of the illness, will trigger the symptoms of the illness.