DAY FOUR

Major Dopamine Pathways

Before you start reading about dopamine pathways, let’s first talk a little about dopamine itself. What is it? Well, dopamine is a chemical in your brain that affects your emotions, movements, and your sensations of pleasure and pain. Dopamine neurotransmitters are located in the deep middle region of your brain called the substantia nigra. There are 5 dopamine receptors and several different pathways through which dopamine can act.

The dopamine hypothesis is a theory espoused by some scientists working to understand the brain. According to the theory, a schizophrenic person is producing too much dopamine. It is not that simple, as you will find out, but the concept behind the dopamine hypothesis has been useful in directing scientists to certain areas of research that have been revealing.

Major Dopamine Pathways in the Brain

Mesocortical pathway
Tuberoinfundibular pathway
Nigrostriatal pathway
Mesolimbic pathway

Select any of the four buttons on the illustration to learn more about each pathway and to understand how inhibition of dopamine in the pathway affects CNS function.

Abnormalities in the synaptic transmission of dopamine are thought to be involved in the pathogenesis of schizophrenia. As shown here, dopamine neurons are organized into 4 well-defined dopamine pathways.

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References

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