The basal ganglia are masses of grey matter located at the base of the forebrain and top of the midbrain. Anatomically, the basal ganglia consist of the corpus striatum, claustrum, and amygdaloid body, while functionally they also include the substantia nigra, subthalamus, and red nucleus. The basal ganglia are involved in controlling voluntary motor activity, timing and scaling movement intensity, and decreasing unwanted muscle activity. Disorders of the basal ganglia include Parkinson's disease, ballismus, chorea, athetosis, Wilson's disease, and Huntington's disease.

1. BASAL GANGLIA
PUBALI KALITA
BPT STUDENT

2. Contents
• Anatomy
• Classifications
• Functions
• Disorders

3. Anatomy --
• Definition :
The basal ganglia are masses of grey
matter embedded within the white matter
of cerebrum .
The basal ganglia are now recognised
as basal nuclei , but the former term is
still commonly used .
The basal ganglia are situated at the base
of the forebrain and top of the midbrain.

4. • Anatomically , it consists of ----
1. CORPUS STRAITUM
2. CLAUSTRUM
3. AMYGDALOID BODY
• Functionally , it consists of ----
1. CORPUS STRAITUM
2. CLAUSTRUM
3. AMYGDALOID BODY
4. SUBSTANTIA NIGRA
5. SUBTHALAMUS
6. RED NUCLEUS .

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9. CORPUS STRAITUM
• Corpus striatum consist of caudate nucleus & lentiform nucleus .
• Caudate nucleus is a C- shaped or comma shaped nucleus . It has head , body
& tail .
• Lentiform nucleus is a large lens shaped (biconvex) nucleus . It is divided into
globus pellidus (medial part ) & putamen (lateral part ) .
• Corpus striatum functionally consist of 2 units – 1) Paleostriatum & 2)
Neostriatum .
• Globus pellidus is included under Paleostriatum .
• Putamen & Caudate nucleus is included under Neostriatum .

10. CLAUSTRUM
• It is a saucer – shaped nucleus situated between the putamen and the insula .
• The word claustrum means ‘hidden away’, and indeed, the claustrum is a thin,
irregular sheet of grey matter, one sheet on each side of the head, concealed
between the inner surface of the neocortex.
• It’s function may be playing a role in synchronizing perceptual, cognitive and
motor processes and knowledge processing

12. AMYGDALOID BODY
• It is a small mass of grey matter attaches to the tail of caudate body .
• Topographically , it is continuous with the tail of the caudate nucleus , but functionally it is
related to the striaterminalis . It is a part of limbic system .

13. SUBSTANTIA NIGRA
• It is located in the mid- brain between the crus cerebri & tegmentum .
• The neurons of substantia nigra produce dopamine .

14. SUBTHALAMIC NUCLEUS
• It is a small mass of grey matter present under the thalamus .
• It is a lens shaped nucleus .
• Only portion of basal ganglia that actually produces an “ excitatory” , glutamate
neurotransmitter .

16. RED NUCLEUS
• It is a paired oval-shaped nucleus .
• It is located in the tegmentum of the midbrain next to the substantia nigra .
• The red nucleus is pale pink, which is believed to be due to the presence of iron in at least
two different forms: hemoglobin and ferritin.

17. FUNCTIONS OF BASAL GANGLIA
1. Control of voluntary motor activity :
• Cognitive control of motor activity .
• Most of the motor actions occur as a consequence of thought process in mind .
• So , basal ganglia is involved in planning and programming of movements .
2. Control of reflex muscular activity :
• Inhibitory effect on spinal reflexes .
• Regulate muscle which maintains posture.
• Mainly visual & labyrinthine reflexes .

18. 3. Timing & scaling of intensity of movements .
4. Decrease muscle tone & unwanted muscular activity .
5. Subconscious execution of some movements :
• Swinging of arm while walking.
• Crude movements of facial expressions with emotions.
• Movement of limbs while swimming .
6. Role in arousal mechanism :
• By connections of globus pallidus and red nucleus with reticular formation .

19. DISORDERS OF BASAL GANGLIA
1. PARKINSONISM
2. BALLISMUS – a) Hemiballismus , b) Monoballismus
3. CHOREA
4. ATHETOSIS
5. WILSON’S DISEASE
6. HUNTINGTON’S DISEASE .

20. Thank You😀