Basal nuclei & their connections
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Transcript of Basal nuclei & their connections
DR. RUSHDAN ZAKARIAHTRAINEE MEDICAL OFFICERNEUROLOGY DEPARTMENT
DMCH
BASAL NUCLEI & THEIR CONNECTIONS
Collection of masses of gray matter situated within each cerebral hemisphere.
The term ‘BASAL’ is used to denote the position of the nuclei at the base of forebrain.
What is Basal Nuclei ?
BASAL GANGLIA
BASAL NUCLEI
PRESENT NOMENCLATURE
ANATOMY
A) CAUDATE NUCLEUS
B) LENTIFORM NUCLEUS (GLOBUS PALLIDUS & PUTAMEN)
C) CLAUSTRUM
D) AMYGDALOID NUCLEUS
Basal Nuclei consists of
A) Sub thalamic nucleus
B) Substantia Nigra (Mid brain)
Functionally Related Nuclei
DEVELOPMENT: TELENCEPHALONMEDIAL GANGLIONIC EMINENCE: Projection neurons for Caudate,
Putamen
LATERAL GANGLIONIC EMINENCE: Projection
neurons for Globus Pallidus & most striated
inter neurons
BASAL NUCLEI ANATOMY
Lies lateral to the lateral ventricles, C shaped, encloses thalamus & internal capsule
o STRUCTURE: Head, Body and Tail
CAUDATE NUCLEUS
CAUDATE NUCLEUS:
Head: Lies into the space of Anterior horn
Body: Forms floor of central part
Tail: Forms roof of inferior horn, joins amygdaloid body
Relationship with Lateral Ventricle
LENTIFORM NUCLEUS:
Globus Pallidus:
Situated medially, got 2 segments,
GPi & GPe
Putamen: Situated laterally
Forms lateral boundary of internal capsule
LENTIFORM NUCLEUS
CLAUSTRUM
AMYGDALOID NUCLEUS
Nuclear mass in temporal lobe,
continuous with tail of caudate
nucleus
Function is closely related to limbic
system or hypothalamus
SUBSTANTIA NIGRA
MEDIUM SPINY NEURON
90% of the neurons
Primary Projection Neurons
Inhibitory (GABAergic)
Very little spontaneous activity
BASAL NUCLEI ANATOMY
BASAL NUCLEI ANATOMY
BLOOD SUPPLY
BLOOD SUPPLY
INPUT & OUTPUTMODULATION
Cerebral Cortex
Substantia
Nigra (Pc)
Thalamus
INPUT
Input modulation
The caudate & putamen receive input from the cortex, and …
… from the thalamus
OUTPUT
Substantia
Nigra (Pr) to
Thalamus
GPi to Thalamus
CONNECTIONS &
PATHWAYS
CONNECTIONS (Afferent and Efferent)
INTRINSIC PATHWAYSDirect Pathway: Striatum > GPi, SNr > Thalamus
Indirect Pathway: Striatum > GPe > STN > GPi, SNr > Thalamus
Net Effects:
Direct pathway: Thalamus (+): Facilitation of movement
Indirect pathway: Thalamus (-):Inhibition of movement
COMPARISON
FUNCTION
Cognition control
Movement Coordination
Voluntary movement control
THANK YOU !