acetylcholine – A neurotransmitter.

akinesia – Inability to initiate voluntary and involuntary movements.

basal ganglia – A deep part of the brain.

bradykinesia – Slow movement.

dopamine – The primary chemical neurotransmitter of the basal ganglia.

dysarthria – Impaired vocalization.

dyskinesias – Abnormal involuntary movements.

dysphagia – Trouble swallowing.

dystonia – Tightness, spasm, or cramping of muscles.

festination – Slow, small, shuffling steps.

freezing – Inability to move or getting “stuck” as with the feet appearing to be glued to the floor.

gait – The manner in which a person walks.

hypomima – A reduction in the movements of small face muscles; masked-like expression.

Lewy body – A round inclusion seen in the dopamine producing nerve cells of substantia nigra which indicates a damaged or dying cell.

masked-like face – A face lacking expression.

micrographic – Very small handwriting.

motor symptoms – Difficulty walking and talking.

non-motor symptoms – Orthostatic hypotension, cardiac dysrhythmias, difficulty completing simple tasks, loss of bladder control, constipation and fatigue.

neuropsychiatric symptoms – Dementia, anxiety, depression, and mental/behavioral changes.

pallalia – Stuttering or stammering speech.

parkinsonian gait – A tendency to lean forward, develop stooped posture, take small quick steps, and no longer swing the arms when walking.

rigidity – A tightness of increase in muscle tone at rest or throughout the entire range of motion.

sialorrhea – Excessive salivation, drooling.

striatum – A part of the basal ganglia circuit that contains dopamine receptors and receives signals from the substantia nigra.

substantia nigra – A part of the brain stem that produces dopamine.

tremor – Rhythmic shaking.