If a difficulty arises in the working of caudate nucleus situated in the basal ganglia, it causes a series of jerky, quasi-purposive movements of the limbs, neck face, etc. which often occur from one part of the body to another, again and again in the same order.
1. Chorea that occurs due to rheumatic fever.
2. Huntington’s chorea (hereditary).
3. Senile chorea.
4. Chorea that occurs in diseases like diphtheria, whooping cough, rubella etc.S.
5. Chorea due to increase in thyroid.
6. Neuroacanthosis Chorea.
7. Chorea due to side effects of the medicines especially drugs for mental disorders, contraceptive pills, lithium, antiemetic drugs (for vomiting), mercury poisoning etc.
As described earlier chorea occurs due to an increase in the levels of the chemical dopamine and so drugs like’ haloperidol, chlorpromazine, tetrabenazine, reserpin etc. (that oppose dopamine) are used.