Degeneration of dopamine-producing neurons in the substantia nigra impairs smooth movement in Parkinson's patients.

“People with Parkinson's have degeneration of neurons in an area of the brain called the substantia which is an area of the brain in the kind of bottom back part of the brain for ufan AOS it's the ventral tegmental area but you don't need to know that name these neurons contain dopamine and are essential for the generation of smooth movement patterns including walking and reaching and moving um one's hand to write Etc”