neuroscience review pmdc step-1 day3
TRANSCRIPT
Prof. Dr. M. Saeed ShafiMBBS, M.Phil, FIAS (UK), DCPS (HPE), MP-HSE(US), FISAMS(PRC)
Member AACA (USA); Member AMEE(UK)
Member Pakistan Medical Research Council
Convenor, PMRC Expert Panel in Anatomy.
Principal &Dean
Sahara Medical College & Sughra Shafi Medical Complex, Narowal-Pakistan
(A Project of SAHARA for Life Trust- Registered Charity in Pak/USA/UK &Japan)
E-mail: [email protected] & [email protected]
URL: www.saharaforlife.org
Learning Outcomes
1.Identify cranial nerves nuclei & pathway; Correlate the
clinical manifestations of their injury to the site of lesion.
2.Interpret Hypothalamo-hypophyseal portal system & its
clinical significance in acromegaly, gigantism, Diabetes
inspidus, normal labour & lactation.
3.Define astereognosis. How it differs from tactile, auditory
or visual agnozia?
4.Interpret transmission of pain & proprioception from
great toe to specific areas of cerebral cortex.
5.Interpret role of thalamus in human brain functioning.
6.Compare & contrast upper &lower motor neuron lesions.
7.Interpret role of limbic system in emotions, memory&
behaviour.
3rd CN
3rd CN
4th CN
6th CN
MLF
5th CN
7th CN
7th CN
Ta
ste
Pa
thw
ay
9th CN
10th CN
11
thC
N
12th CN
Boundaries between
• Midbrain and diencephalon
– Posterior commissure Mammillary bodies)
• Diencephalon and Telencephalon
– (Interventricular foramen Optic Chiasma)
Components of Diencephalon
• Thalamus
• Hypothalamus
• Subthalamus
• Epithalamus
• Metathalamus
Morphology of thalamus
• Largest sensory relay station to cortex
• 3 x 1.5 x 1.5 cm
• Medial, Lateral, Dorsal &Ventral Surfaces
• Relation to 3rd ventricle & internal capsule
• Divisions into nuclei
• External medullary lamina
• Internal medullary lamina
Medial Geniculate nucleus
• AFF: Inferior Colliculus / inferior branchium
• EFF: Auditory radiations to Temporal lobe
Lateral geniculate nucleus
• AFF: Retina / OT / opposite visual filed
• EFF: Geniculocalcarine tract
VPN
• AFF: ML / SL / TL
• EFF:
– Sensory cortex (3,1,2,5,7)
– Medial nucleus
– Nonspecific nuclei
VA & VL nucleus
• AFF:
– Dentate N.
– Substantia nigra
– Corpus striatum
• EFF:
– Motor cortex (4,6)
Nonspecific nuclei
• AFF:
– VPN
– Intralaminar Nuclei
• EFF:
– Association cortex
Thalamic syndrome
• Korsakoff’s syndrome
• Sensory loss of opposite ½
• Threshold to pain increase
• Spontaneous pain, laughing, crying
• Intractable pain
• Emotional instability
• Amnesia
Subthalamus
• Subthalamic N.
• Fiber tracts – dentatothalamic SL, ML, TL,
Lenticular fasciculus, Ansa lenticularis
• Substantia nigra
• Zona incenta (Red nucleus)
• Hemiballisnus ?
Epithalamus
• Pineal gland
– Biological clock + circadian rhythm
– Neuroendocrine tranducer
– Epiphysis cerebri
• Habenular nucleus
– AFF:• Stria medullaris thalami, Stria terminalis
– EFF: • Habenulo interpeduncular fasciculus
Hypothalamus
• Medial area – Suprachiasmatic
• Supraoptic nucleus
• Paraventricular nucleus Hypothalamohypophygeal tract
• Anterior nucleus / preoptic area
– Tuberal • Ventromedial tuberal nucleus
• Dorsomedial nucleus
• Arcuate nucleus
– Mamillary • PHN
• MMN
• LMN
• Lateral area
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