Basal Ganglia


Basal Ganglia, Dorsal Striatum, Caudate Nucleus, Putamen, Globus Pallidus, Substantia Nigra, Nucleus Accumbens, Subthalamic Nucleus

  • Definitions
  1. Basal Ganglia
    1. Collection of Neurons and their nucleii near the Thalamus that function to coordinate movement
    2. Counters the excitatory signals from the Cerebellum to result in smooth movement
    3. Interconnections to the Cerebral Hemispheres, Cerebellum, Thalamus and Brainstem
  • Anatomy
  • Components
  1. Globus Pallidus
  2. Dorsal Striatum (Putamen, Caudate Nucleus)
    1. Medial Dorsal Striatum (Caudate Nucleus)
    2. Internal Capsule (courses between the Caudate Nucleus and Putamen)
    3. Lateral Dorsal Striatum (Putamen)
  3. Nucleus Accumbens
  4. Substantia Nigra (Midbrain)
    1. Divided into the pars compacta and pars reticulata
      1. Melanin containing cells in pars compacta produce Dopamine which is transmitted to the Dorsal Striatum
      2. Parkinsonism results when Dopamine production is deficient
    2. Functions
      1. Movement including eye movement (see Pars compacta as above
      2. Reward-seeking and addiction
  5. Subthalamic Nucleus
  • Anatomy
  • Images
  1. neuroBrainXsGrayBB716.gif Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
  2. neuroStriatumGrayBB741.gif Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
  • Pathophysiology
  1. See Movement Disorder
  2. Parkinsonism
    1. Associated with rigid slow movements, resting Tremor, shuffling gait, mask-like facies
    2. Basal Ganglia degeneration
    3. Substantia Nigra degeneration
  3. Athetosis
    1. Slow, writhing movements (esp. hand, wrist)
  4. Chorea (e.g. Huntington's Chorea, Sydenham's Chorea)
    1. Sudden, jerky movements
  5. Hemiballismus
    1. Sudden, incoordinated flailing of an extremity
  • References
  1. Goldberg (2021) Clinical Physiology, Medmaster, Miami, p. 106
  2. Goldberg (2014) Clinical Neuroanatomy, Medmaster, p. 61-4
  3. Netter (1997) Atlas Human Anatomy, ICON Learning, p. 104