Applied Anatomy:

Deficits of basal ganglia function fall into one of the two categories:

  • Presence of extraneous unwanted movements.
  • Absence of, or diffficulty with intended movements.


Parkinson's disease

Caused by loss of dopaminergic neurons of the substantia nigra. Presents with three main symptoms:

  • Tremor, most apparent at rest.
  • Rigidity.
  • Bradykinesia or akinesia.

Huntington's disease

  • Results from degeneration of the caudate and putamen. It may be hereditary.
  • There is continous slow writhing vermicular involuntary movements of the face and limbs. The movements blend with each other to give the appearance of a continous mobile spasm.
  • When the movements involve axial muscles, they produce severe torsion of the neck, shoulder and pelvic girdle.


  • This is a brisk, graceful series of successive involuntary movements of considerable complexity. They resemble fragments of purposeful voluntary movements.
  • The movements involve distal portions of the extremities, the muscles of the facial expression, the tongue and muscles of swallowing.


  • This is invariably associated with lesions of the sub thalamic nucleus, and its connections.
  • This is a violent forceful, flinging movement involving primarily the proximal appendicular musculature, around the shoulder and pelvic girdles.