Global institute of medical sciences 1. www.gims-org.com 2. www.usmletutor.org 3. www.mciscreeningtest.com

1. High yield FMGE - Neuroanatomy
NEURO ANATOMY
 Schwann cells - Myelin production in cns
 Oligodendrocytes - Myelin production in cns
 The fastest conduncting fibres are TYPE-A fibres
 TYPE-A:-
 α – Muscle spindle { Extra fusal muscle fibres }
 γ – Intra fusal muscle fibres
 δ – Collaterls to Aα
 Type-B:-
 Supplies preganglionic autonomic fibres and receives information
from skin,viscera,connective tissue .
 TYPE-C:-
 These are unmyelinated
 Sends efferents to post ganglionic autonomic fibres
 Jumping of AP from one node to other is Saltatory condunction
 Fibrous Astrocytes – Blood Brain Barrier {BBB}
 Spinal cord ends at L2 Verterbra
 Laminae I – Marginal cell
 Laminae II – Substantia gelatinosa of Rolando
 Laminae III – Chief – sensory cells
 Laminae IV – Clrake’s cells
 Laminae IX –Substantia gelatinosa centralis
 The occulomotor nerve emergsfrom medial aspect of crus cerebri
 The Trochlear nerve emergs from lateral aspect of crus cerebri
 A pair of superior and inferior colliculi forms corpora quadrigemina
 Telencephalon – Cerebral cortex , Basal ganglia
 Diencephalon – Thalamus , Hypothalamus
 Mesencephalon – Midbrain , cerebral penduncles
 Rhombcephalon – Pons , cerebellum , Medulla
 Spinal cord develops from the downward Continuation of Neural Tube
 Anterior Spinothalamic Tract – Crude touch sensations , Chief-Sensory cell
Global Institute Of Medical Sciences – www.gims-org.com

2. High yield FMGE - Neuroanatomy
 Lateral Spincothalamic Tract – Substantia geltinosa , Pain and
Temperature
 Renshaw cell –Laminae VII
 Laminae -IX – α OR γ Motor neurons
 Medulla oblongata –3cm length , 2cm width
 Anterior surface of pons is marked in the midline by shallow groove which
contains Basilar Artery
 Cerebello pontine angle has Facial Nerve , Vestibulo cochlear Nerve and
Glossopharyngeal Nerve emergs from Medial To Lateral
 Spinal nucleus of trigeminus presents on the Lateral aspect of medulla ,
More medially nucleus gracilis and nucleus cuneatus
 Medial lemniscus is formed by fibres arising from nucleus gracilis and
nucleus cuneatus
 Cerebrum and cerebellum are separated by Tentrioum cerebella
 Cerebellar nuclei – Dentate , Emboli form , Globose ,Fastigeal
 Dentate is the largest form of cerebellar nuclei
 Anterior spinal artery – Anterior 2/3 of spinal cord
 Posterior spinal artery – Posterior 1/3 of spinal cord
 Greater Anterior segmental medullary artery – Adam Kiewilz
 Directly arising from aorta
 Major source of blood to lower third of spinal cord
 Spinal shock is more common in Lower Third Of Spinal cord
 Anterior Longitudinal artery and Intra medullary arteries are end arteries
of spinal cord
 Spinal shock is seen Most common in Thoracic and Lumbar Area
 Lumbar spinal shock - Most common Abdominal Aortic Aneurysm
 Synaptic cleft - 20 - 40 nm Wide
 Subconscious Kinesthetic sensations from upperlimb – Cuneocerebellar
Tract
 Toxin induced neuronal degeneratiob – Injury to dorsal columns
 Lateral spinothalamic and anterior spinothalamic ascends in the form
Of spinal Lemniscus
 Dorsal spino cerebellar tract – Clarke’s column
Global Institute Of Medical Sciences – www.gims-org.com

3. High yield FMGE - Neuroanatomy
 Ventral spino cerebellat tract – Marginal cell
 Spino cerebellar tract carries Subconscious kinesthetic sensations
 Syringomyeliea – Dorsal Column Injury – Sensory Loss
 ARAS – Conscious And Awarness
 Upper motor neuron { UMN } – Spastic Paralysis
 Lower motor neuron { LMN } - Flaccid Paralysis
 Babinski sign positive – UMN Lesions
 CSF – 150 Ml
 Globus Pallidus + putamen = Lentiform Nucleus
 Lentiform Nucleus + Caudate Nucleus = Corpus Striatum
 Corpus striatum is important for Intelligence and Longterm Memory
and Development of IQ
 Flow of CSF from Lateral 2/3 rd ventricle – Foramen of Monro
 CSF from 3rd – 4th ventricle – Aqueduct of sylvius
 Area 4 – Primary Motor Area
 Area 6 – Pre Motor Area { Association Area }
 Area 8– Frontal eye field { Conjugate Movements of eye ball }
 Area 9,10,11 – Controls personality and intellect
 Area 3,2,1 – Primary sensory area
 Damage to somato sensory area causes deficit in fine touch ,position
and vibration sense ( Dorsal columns are more commonly involved )
 Area 17,18,19 – Visual Cortex
 Area 17 – Primary Visual Area
 Area 18 – Visual Association Area
 Area 19 – Identification and Analyzing
 Area 41 – Primary Auditory Area
 Area 42 – Auditory Association Area
 Area 22 – Wernicke’s Area
 Area 44,45 – Broca’s Area
 The posterior limb of internal capsule contains Cortico spinal tract
 Blood supply of internal capsule – Middle cerebral artery
 Specific Gravity of CSF – 1.005
 Concentration of Nacl is high in CSF when compared to plasma
Global Institute Of Medical Sciences – www.gims-org.com

4. High yield FMGE - Neuroanatomy
 Production of CSF – 0.3 ml / min
 Thalamus is supplied by Posterior cerebral Artery (75%) , Middle
Cerebral Artery (25%)
 Thalamus - Striate Vein - Venous Drianage of thalamus
 Lateral Hypothalamic Area considered as feeding ccentre
 Hypoglossal nucleus – Innervates Styloglossus and Genioglossus
 Arterial Supply Of Medulla
 Anterior spinal artery – Branch of veretebral artery
 Posterior spinal artery – Branch of veretebral artery
 Posterior inferior cerebellar artery –Branch of verterbral artery
 Substantia Nigra :-
 Dorsal part – Pars Compacta
 Ventral part –Pars Reticularis
 Pars Compacta contains Dopaminergic and Cholinergic Neurons
 Pars Reticularis contains Dopaminergic Neurons
 Trochlear Nerve is the only cranial nerve arises from Dorsal aspect of
brain { Posteriorly }
 Lesion in red nucleus causes Benedict’s syndrome
 Paranaud’s syndrome – Tumor at superior collicular which
compresses pineal body
 Blood supply of pons – Superior Cerebellar Artery , Posterior –
Inferior Cerebellar Artery
 Archicerebellum – Lingula + Floculla
 Function : Equilibrium – Tone and Posture of trunk muscles
 Paleo cerebellum – Tone and Posture of Anti gravity muscles
 Neopallial cortex – Skilled Movements
 Climbing Fibers , Mossy Fibers , Granular Fibers – { Excitatory
Neurotransmitters are Aspartate , Glutamate }
 Purkinjie cell – Neurotransmitter – GABA
 BBB is absent in Posterior Pituitary , Median Eminence , Pineal
Gland
 Putamen – Anterior Cerebral Artery
 Anterior Chorodial Artery – Optic Tract , Optic Chiasma
Global Institute Of Medical Sciences – www.gims-org.com

5. High yield FMGE - Neuroanatomy
 Globus pallidus – Straite Arteries – Branch of middle cerebral artery
 Tail of caudate nucleus and amygdaloid body are perforating
branches of middle cerebral artery
 Lesions in corpus striatum – Parkinsonism
 The cranial nerve which does not have parasympathetic component
–Abducens Nerve
Global Institute Of Medical Sciences – www.gims-org.com