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					Basal Nuclei
Location And Subdivisions Of Basal
             Ganglia
Location :
Subcortical, lies deep within the cerebral
  hemispheres

• Consist of the caudate nucleus, putamen,
  globus pallidus and substantia nigra
Putamen
Caudate
   nucleus
Globus
   pallidus
Thalamus
• The caudate nucleus and putamen along with the
  interposed anterior limb of the internal capsule are
  collectively known as the corpus striatum (i.e.
  striated body) because of their appearance.
• Similarly, the shape of the putamen and globus
  pallidus resembles a lens, and they are collectively
  called the lenticular nucleus.
• Basal ganglia associated with motor and learning
  functions
• It influences the skeletal muscle tone.
• Establishes postures.
• Controls voluntary movements
• Selects and maintaining purposeful motor activity
• Suppresses unwanted or useless movement.
• Monitor and coordinates slow, sustained contractions
  related to posture and support.
• Inhibits muscle tone throughout the body; proper
  muscle tone is normally maintained through a balance of
  excitatory and inihibtory inputs to the neurones that
  innervate skeletal muscle
• When the basal nuclei are affected by disease - say in
  disorders like Huntington disease, Parkinson’s disease or
  Wilson’s disease - the person has unwanted movements,
  such as involuntary jerking movements of an arm or leg or
  spasmodic movement of facial muscles.

• Injury to this area leads to rigidity, hypotonia

• In addition the basal ganglion houses the amygdala, which
  mediates inborn and acquired emotional responses.

• Mediates both conscious and unconscious emotional
  feelings. It connects, among other places, into the prefrontal
  lobe.
Disorders linked with the basal
            ganglia
• Huntington's disease
• Parkinson's disease
• Tourette's disorder
• Obsessive-compulsive disorder
• Attention-deficit hyperactivity disorder (ADHD)
• Athymhormic syndrome (PAP syndrome)
• Cerebral palsy: basal ganglia damage during
  second and third trimester of pregnancy
• Tardive dyskinesia, caused by chronic
  antipsychotic treatment
Structure-Function
Wilson Disease
  (Hepatolenticular Degeneration)
  Inheritance of a mutation on chromosome 13.
   The mutation prevents the body from eliminating
  excess copper.
Ceruloplasmin is the protein that binds and removes
  excess copper and its levels are greatly reduced in
  this disorder. Too much copper in the system
  damages the cells of the liver and leads to
  cirrhosis. Neurological damage primarily occurs in
  the putamen and globus pallidus, collectively known
  as the lenticular nucleus.
    Symptoms : -
•   A peculiar type of tremor in the upper extremities,
    slowness of movement and changes in
    temperament.
•    Persons may become exceptionally
    argumentative,
•   Overly emotional
•   Decrease in mental capabilities.
•   Kayser-Fleischer rings (a rusty brown
    discoloration at the rims of the corneas) as the
    copper begins to affect the nervous system.
•    The disease first affects the liver, and if treatment
    is administered early enough, damage to the
    nervous system is dramatically reduced.
  Treatment
• Elimination of copper containing foods such
  as chocolate and mushrooms.
• Chelate excess copper and eliminate it from
  the body.