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: msaeedshafi@hotmail.com & principal@saharaforlife.org

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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