Movement disorders, basal ganglia.

Basal ganglia, dysfunctions.

Functional disorders linked to the basal ganglia manifest themselves primarily as changes in our normal movement patterns.
A distinction is usually made between hypokineticand hyper-kineticdisorders.

A hypokinetic disorder involves uncontrollable/involuntary impairment of muscular activity (hypokinesia) and is characterized by one or more of the following symptoms:
Akinesia = inability to perform a movement.
Bradykinesia = slow movements.
Dysarthria = speech difficulty.
Rigidity = muscle stiffness.
Tremor = tremors.
Postural instability = difficulty maintaining a normal body position.
Hypokinetic disorders are usually due to reduced activity along the "Direct pathway through the basal ganglia".
Parkinson's disease is the textbook example of a hypokinetic disorder.

A hyperkinetic disorder is an uncontrollable/involuntary increase in muscular activity (hyperkinesia/dyskinesia/dystonia) and is characterised by one or more of the following symptoms:
Athetosis = slow distorting, snakeing, movements of the arms, legs, torso and/or face. The symptom is seen, among other things, in people with cerebral palsy (CP).
Hemiballism = one half of the body performs continuously and again a movement pattern similar to that of throwing a ball. The symptom is rare and is caused by an injury in the subthalamic core of the opposite side.
Chorea = dancing sickness; involves sudden series of jerky and throwaway movements in different body parts. This includes the hereditary Huntington's chorea.
Myoclonus = short-term sudden contraction of one or more muscles. The symptom occurs in a variety of serious neurological diseases, e.g. multiple sclerosis, Alzheimer's disease, Parkinson's disease. Hiccups and "that sudden muscle twitch", just as you are about to fall asleep, are benign examples of myoclonus.
Tics = short-term sudden, more or less, controllable contraction of one or more muscles usually on the face and usually connected to one eye, nose or mouth.
Hyperkinetic disorders are usually due to impaired/disturbed activity along the "Indirect pathway through the basal ganglia".