BASAL GANGLIA

1. BASAL GANGLIA
DR TANAYA BARUAH

2. ANATOMY
• Basal ganglia include
1. Corpus striatum
2. Substantia nigra ( pars compacta and pars reticularis)
3. Subthalamic nucleus of Luys
4. Ventral tegmental area.
• The corpus striatum comprises the
1. Striatum proper (or neostriatum)
• Putamen
• Caudate nucleus
• nucleus accumbens
2. Globus pallidus (or paleostriatum)
• medial or internal (Gpi)
• lateral or external (Gpe)
3. ventral pallidum, with its internal and external portions.

4. Basal ganglia are responsible for
• automatic execution of learned motor plans
• movements that have been “laid down by practice” and that are
subconscious.

5. • Parkinson disease (PD) to deficient dopaminergic neurotransmission
in the striatum consequent to the death of dopaminergic neurons in
the substantia nigra pars compacta (SNc)
• Choreic movements in Huntington disease (HD) are linked to the
death of medium spiny neurons in the caudate and putamen.
• Hemiballism (HB) is typically associated with structural lesions in the
contralateral subthalamic nucleus (STN) or its afferent or efferent
connections

6. Animal models
1. 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD
2. Excitotoxic and transgenic models of HD
3. STN lesion model of HB
• confirm the central role of disordered basal ganglia function in these
conditions

7. References :
1. Bradley 8th ed
2. Dejong 8th ed chptr 26
3. Bd chaurasia