Understanding Extrapyramidal Symptoms in Movement Disorders

Extrapyramidal refers to a group of neurological symptoms that are not directly related to the dopamine-producing neurons in the brain, specifically those located in the substantia nigra and the ventral tegmental area. These symptoms can occur in conditions such as Parkinson's disease, Huntington's disease, and other movement disorders.

The term "extrapyramidal" was coined to distinguish these symptoms from those that are directly related to the dopamine-producing neurons, which are called "pyramidal" symptoms. Pyramidal symptoms include tremors, rigidity, bradykinesia (slowness of movement), and loss of autonomic function.

Extrapyramidal symptoms can include:

1. Dystonia: a sustained or intermittent contraction of muscle groups that can cause abnormal postures or movements.
2. Chorea: an irregular, jerky movement that can affect the limbs, face, or tongue.
3. Athetosis: a slow, writhing movement that can affect the hands and feet.
4. Ballism: an excessive, large-amplitude movement that can affect the arms and legs.
5. Oculogyric crisis: a sudden, sustained upward deviation of the eyes that can be accompanied by neck stiffness and resistance to movement.
6. Tardive dyskinesia: a delayed, abnormal movement that can affect the face, tongue, or limbs.
7. Dysmetria: an abnormal increase or decrease in the range of motion of a body part.
8. Incoordination: a difficulty with coordinated movement.
9. Gait disturbances: abnormalities in walking pattern, such as a shuffling gait or a wide, unsteady gait.
10. Cognitive changes: difficulties with memory, attention, and other cognitive functions.

These symptoms can be caused by a variety of factors, including genetic mutations, injury to the brain, and certain medications. They can also be a side effect of deep brain stimulation, a surgical procedure used to treat movement disorders such as Parkinson's disease.