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contains axons
of cortical neuronal cell bodies, traversing across and connecting corresponding regions of the
opposite cerebral cortex.

1 superior colliculus
2 periaqueductal grey
3 cerebral aqueduct
4 edinger westphal subnucleus
5 oculomotor nucleus
6 red nucleus
7 substantia nigra
8 cerebral peduncle
9 interpeduncular fossa

six,

five somatic subnuclei supply the motor inntervation for 4 of the 6 extraocular muscles that move each eye plus levator palpebrae superioris which elevates the uper eyelid
one medially situated parasympathetic edinger westhhal subnucleus.

superior orbital fissure

upper diviison and lower division

upper division: superior recturs and levator palpebrae superioris

lower division: medial rectus, inferior rectus and inferior oblique

trochlear

abducens

ciliary ganglion
postganglionic fibres run in the short ciliary nerves to sclera, pierce the lamina cribrosa and supply the ciliary and sphincter pupillae muscle

when light is shown on one eye it causes the the one but also the other to constrict (consensual light reflex)

complete 3rd nerve paralysis
- ptosis of the eyelid( uppossed action of orbicularis oculi)
- dialted non reactive upil (uopposed dilator pupillae)
- full abduction and depression fo the eye (unapposed lateral recuts and superior oblique)

parasympathetic fibres become compressed as they are the most superficial ones and are comressed against the petrous part of the temporal bone
causes pupil of affected side to dilate progressivley
may be caused by increased intracranial pressure and sxtra or subrudal ahemtatoma  (pupoils shoudl also be monitored in head injury, indicate compression)

inferior coliculi (go around periaquedcut and emerge ot dorsal surface inferior to inferior colliculi on the contralaertal side)

superior oblique

superior oribital frissure

1 trohlear nerve
2 inferior colloculus
3 cerebral aquiduct
4 periaquiductal grey matter
5 trochlear nuclues
6 median longitudional fasciculus
7 desuccation of superior cerebellar peduncles (cerebellar-rubro-thalamic pathway)
8 substantia nighra
9 cerebral peduncle
10 interpeduncular fossa
11 oculomotor nerve

double vision (down and out diplopia) when looking downwards

torticollis ( coensatory tiliting of the head to the side oposite the palsied ee

eye driting upwards, as superior oblique is paralysed, it normally helps the inferior rectus to pull the eyeball dwonwards in medial position . this is known as hypertropia.

1 levator palprae superioris
2 superior rectus
3 medial recturs
3 inverior rectus
4 lateral rectus
5 inferior obliaue
6 superior obliqze

1 superior rectus
2 sclera
3 choroid
4 ciliary muslce
5 ciliary process
6 ciliray body
7 posteror chamber
8 scleral venous sinus
9 dilator pupillae
10 iris
11 sphincter pupillae
12 conrea
13 anteror chmaber
14 zona fibres
15 lens

sensory

muscles of mastication (temporalis, masseter, medial and lateral pterygoid)

lie in the floow of the forth vetnricle at the level of the facial colliculi,
fibres run anteriorly and ipsilaterally though the pons to emerge at the inferior border near the midline

superior orbital frissure

lateral rectus muscles (ABducts)

1 facial colliculus
2 abducens nucleus
3 facial nucleus
4 pramidal tract
5 root of abducens nerve

muscles dervied form the second branchial arch wich are the muscles of facial expression as the
stapedius
posterior belly of the occipitofrontalis
stylphyoid
posterior belly of digastric

facial nerve though internal jugular foramen
no

sensory
one motor nerve to the stylopharyngeus

tympanic branch (sensory) and carotid branch

is sensory to the tympanic cativy where it suppplies the middle ear

affernt fibres project to the spinal trigeminal nucleus

parasympathetic  fibres of the tympanic nerve originate form the infeiror salivatory nucles ( part of the nuclei of the CN 9) and continue form the tympnaic plexus in the middle ear as the lesser petrosal nerve (the part of the typmanic nerve that is parasympathetic) to the otic gangion which which postgangionic fibres run in the auriculotemporal nerve (branch of the mandibular nerve v3) to supply the parotid gland.

carries afferent barorepective fibres which originate in the carotid sinus which are sensitive to systoic blood prssure. They procjet to the baroreceptor region of the nuclues solitarous

chemorecetpive fibres which supply the glommus cells ot the carotid body monitoring CO2 and O2 levels and projet to the dorsal resporatory region fo the nucleus solitarius

nucleus ambigous (This nucleus gives rise to the somatic efferent motor fibers of the vagus nerve (CN X) terminating in the laryngeal and pharyngeal muscles, as well as to the efferent motor fibers of the glossopharyngeal nerve (CN IX) terminating in the stylopharyngeus)

afferent fibres

-supply sensation to the posterior thir of the tongue ( gag reflex)
-musouc membrane
-taste fibres of the cicumvallate papillae at the back of the tongue project to the gustatory region o the nucleus solitarious

VISCERAL AND TASTE FIBRES ALL END IN THE NUCLEUS SOLITARIUS

AFFERENT FIBRES OF GENERAL SENSATION END IN THE TRIGEMINAL SENSory NUCELUS

internal jugular with the 9 and 11, sharin a sheath
forms a suerior jugular ganglion and a inferior nodose gangion both of which are sensory.

auricular branch
carries cutaneous sensation form the skin lining the external auditory meatus

menigeal branch
carris sensation form the postteror cranial fossa

both have their cell bodies in the jugular ganglion and their central processes project to the spinal trigeminal nucleus.

dorsal nucleus of the vagus ( nerves to alimentry tract between lower oesi and transverse colon)

nucleus ambiguus
fibre serving heart and lungs

arise form  nucleus ambiguus
form braches the pharyngeala nd the laryngeal of the vagus which supply :
solft palate, larnyx pharyx, levator palatini, upper striated muscles of the oesi
-> imortant for speech and swallowing

form heart and respiratroy and alimentary tracts
inferior nodose gangion
comissural region of the nucleus solitarius

motor
nucleus of the accessory  nerve (column af alpa and gamma neurons)
enter the cranium though the foramen magnum and leateit again through the jugular foramen
sternocleidomastoids  (alsong with C2 and 3)
trapezius  (along with c3 and 4)

somatif efferents
extrnsic and intrinsic muscles fo the tongue
reticular neurons (for automatic of reflex movements in eating of swallowing) and cortical fibres (for speech articulation)
hypoglossal canal

entrapemnt of any of the last four cranial nerves and or the neraby carotid nerve

tumor (primary form the nasopharynx or secondary from the uper cervical lymph nodes)

symptoms :
- pain in or behind ear due to irritation of the auricular branches of the 9 and 10
- headache due to irritation of the meningeal branch of 10
-hoarseness due to paralysis of the laryngeal nerves
- dysphagia (diffiuclty to swallow) due to paralysis of the pharyngomotor fibres
- honers syndrome ( ptosis of upper eyelid, pupillary constriction) due to interruption of sympathetic internal caortid nerve
- wasting of affected side of tongue and deviation of the protruded tongue to the affected side due to infranuclear paralysis of 12
- deviation of teh uvula away form the affected side due to unoposed action of levator palatini
- sensory loss in oroharynx on the affected side
- inabllity do adduct the voral cord to the midline
- weakness and wasting of sternocleidomastoid and treapezius due to interruption of 11

sympathetic signs may be absend if accessory nerves will be unaffected

vertebral arteries (from subclavian) and internal carotid (from common carotid)

1 hypophyseal branch wiithin the cavernous sinus to the neurohypophysis ( pituitary protal system)
2 opthalamic artery ( to orbit though optic cancal) supplies the following structures: - structures in orbit,
- the frontal and ethmoidal sinuses
-frontal scalp
-dorsum of  nouse
3  anterior choriodal artery supplies optic tract choroid plexus  of the ltateral ventrilce, hippocampus, deep structures of the cerebral hemisohere like the internal capsule and the pallidum
4 posteror communicating artery anastomses then with the posterior cerebral artery and forms the cerebral arterial circle of willis
5 and 6 terminal branches of it are the anterior and middle cerebral arteries

lateral surface of the frontal, parietal and temoral lobes, including the primary motor and sensory cortices and the whole of the body excpet hte lower limb and the auditory cortex and insula

motor and sensroy cortices of the lower limb
marrow miedial band ot the external surface of the frontal lobe and parietal cortices

anterior and posterior spinal arteries suppplying the medulla and spinal cord
posterior inferior cerebellar artery ( suppplies the inferor aspect of the cerebellum=
as the verteberal arteries merge together, they form the basilar artery which gibes rise to hte anteror inferior cerebllar artery (supplies the anterior and inferior part of hte cerebllum)
pontine branches
superior cerebral arteries (supplying the visual cortex and occpiputal lobe)

posterior communicating arteries

cerebrovascular accident (CVA)
ictus cerebri

sudden occlusion of the cerebral artery
rupture of blood vessel (cerebral haemorrhage)

focal epilepsy contrallteral sennsory motor deficit and psychological deficits (aphasia)

focal brainstem syndrome

1 posterior cerebral artery
2 middle cerebral artery
3 anterior communicating artery
4anterior cerebral artery
5 left internal carotid
6 basilar artery
7 vertebral artery

1 anterior cerebral artery
2 middle cerebral artery
3 anterior communicating artery
4 posterior cerebral artery
5 posteror communicating artery
6 internal carotid artery
7 common carotid artery
8 vertebral arteries
9 external carotid artery (not so important)
10 basilar artery
11right middle cerebral artery
12 circle of willis

A Granule cell (ranule cells refer to tiny neurons (a type of cell) that are around 10 micrometres in diameter. Granule cells are found within the granular layer of the cerebellum, layer 3, inner most layer, of cerebellar cortex. Cerebellar granule cells account for nearly half of the neurons in the central nervous system. Granule cells receive excitatory input from mossy fibers originating from pontine nuclei. Cerebellar granule cells send parallel fibers up through the Purkinje layer into the molecular layer where they branch out and spread through Purkinje cell dendritic arbors. These parallel fibers form thousands of excitatory synapses onto the intermediate and distal dendrites of Purkinje cells using glutamate as a neurotransmitter)
b molecular layer
c purkenje fiber
d granular layer
f white layer
g Climbing fibres from
inferior olivary nucleus
h mossy fiber

a molecular layer
b purkenje layer
c granular layer
d mossy fiber
e climbing fiber
ff deep nucleus
g purkenje fiber
h basket bell
i golgi cell
j stellate cell
k climbing fiber
l Parallel fibre
from granule
cell

the striatum (or neostriatum);
-caudate nucleus
-nucleus accumbens
- putamen
• the pallidum (= globus pallidus)
- lateral segment
- medial segment
• subthalamic nucleus
• pars compacta of substantia nigra

a body of caudate nucleus
b tail of caudate nucleus
c putamen
d lateral pallidum
e medel palidum
f nucleus accumbens
g head of caudate nucleus
h internal capsule
i amygdala
j putamen

involved in the control of posture and movement.
corpus striatum (because of striations of grey matter across the
internal capsule in some planes of section).

the cerebral cortex
the thalamus
substantia nigra
• Corticostriatal fibres o
• Thalamostriatal fibres o.
• Nigrostriatal fibres

the lateral and medial segments of the pallidum (striatopallidal fibres) and the pars reticulata of the substantia nigra (striatonigral fibres). they use gaba as their neurotransmitter which is inhibitory fo the pallidal and nigral neurons.

striatal GABAergic neurons (as mentioned above), as well as the
subthalamic nucleus (a small diencephalic structure lying beneath the thalamus and against the medial surface of the internal capsule).

subthalamic nucleus and subthalamic fasciculus.
inhibitory, GABAergic pallidosubthalamic fibres also travel in the subthalamic
fEfferent fibres of the medial segment, also inhibitory and GABAergic, project principally, along with fibres of the pars reticulata of the substantia nigra, to the thalamus

nuclei in the thalamus, project excitory fibres to the primary and supplementary motor cortices

corticospinal and corticobulbar pathways (via the spinal cord and brainstem, respectively), but also to the
neostriatum (the caudate nucleus and putamen) via excitatory, glutamatergic fibres.

a striatum
b amygdala
c neostratium
d paleostratium
e cudate nucleus
f putamen
g pallidum
h lentiform nucleus

2, 3, 5
glutamate and asparate

lamina IVd form glutamatergic synapses on pyramidal cells

lamina IV,  form inhibitory γ-aminobutyric acid (GABA)ergic synapses on other pyramidal cells.
axodendritic (onto the bases of spines of pyramidal
cell dendrites),
axosomatic (onto the soma of pyramidal cells, also known as basket cells)
and axoaxonal (onto the axons of several pyramidal cells, also known as chandelier cells).

6

olfaction (smell)
memory

I. Molecular Layer containing tips of apical dendrites of pyramidal cells as well as the most
distal branches of corticothalamic axons of the intralaminar nucleus of the thalamus.
II. Outer Granular Layer containing small pyramidal cells which establish intracortical
connections.
III. Outer Pyramidal Layer containing medium-sized pyramidal cells which give rise to
association and commissural fibres, and stellate cells.
IV. Inner Granular Layer containing stellate cells, especially in the primary somatosensory,
primary visual and primary auditory cortices, and which receive thalamocortical
afferents
V. Inner Pyramidal Layer containing large pyramidal cells projecting to extracortical targets
including the corpus striatum, thalamus, brainstem and spinal cord
VI. Fusiform Layer containing modified pyramidal cells projecting to the thalamus†

1. Long or short association fibres from small and medium-sized pyramidal cells of the ipsilateral cortex. Long association fibres arise in  another lobe, while short association fibres arise much closer, often in a neighbouring gyrus
2. Commissural fibres from medium-sized pyramidal cells projecting mainly through the corpus callosum from matching areas in the contralateral hemisphere.
3. Specific thalamocortical fibres from the appropriate specific or association nucleus (e.g. from the ventral posterior thalamic nucleus → somatosensory cortex; from the dorsomedial thalamic nucleus → prefrontal cortex).
4. Non-specific thalamocortical fibres from the intralaminar nuclei.
5. Cholinergic and aminergic fibres from the basal forebrain, hypothalamus and brainstem.

1. Short association fibres (e.g. those entering the primary motor cortex from the primary somatosensory cortex) and long association fibres (e.g. those projecting back from the
prefrontal cortex to sensory association areas of the parietal lobe).
2. Commissural fibres running across the corpus callosum, anterior commissure and other  minor commissures, to matching areas in the contralateral cortex.
3. Projection fibres, especially
a. corticostriatal (from primary motor and somatosensory cortices to the basal ganglia)
b. corticothalamic (from all areas of cortex to the thalamus)
c. corticopontine (to ipsilateral pontine nuclei)
d. corticonuclear (to contralateral motor and somatic sensory cranial nerve nuclei in the
pons and medulla)
e. corticospinal (to motor neurons of the anterior horn of the spinal cord)

1. An outer, fibre-rich Molecular layer
2. An intermediate Purkinje∗ cell layer
3. An inner Granular layer, dominated by granule cells

a purkinje cell layer
b  molecular layer
c white matter
d granular layer
e purkinje cell
f molecular layer
g granular layer

1. spinocerebellar fibres (from the spinal
cord)
2.olivocerebellar fibres (from the inferior olivary nucleus of the medulla oblongata),
3. vestibulocerebellar fibres (from the vestibular nuclei), and 4.pontocerebellar fibres (from the
pons). T
they mostly terminate in the cerebellar cortex where they are excitatory to cortical neurons.
Afferent fibres enter through one of the cerebellar peduncles and proceed to the cortex as either mossy fibres or climbing fibres, depending on their origin (only the olivocerebellar fibres end as climbing fibres). Each mossy fibre branches to supply several folia,
ending in the granular layer in synaptic contact with granule cells.

2, 3, 5
glutamate and asparate

2, 3, 5
glutamate and asparate

2, 3, 5
glutamate and asparate

medial gracile fasciculus carrying fibres from the lower trunk and lower
limb, the lateral cuneate fasciculus carrying fibres from the upper trunk and upper limb.
The second order afferents arise in the gracile and cuneate nuclei,

The medial lemniscus, also known as Reil's band or Reil's ribbon, is a pathway in the brainstem that carries sensory information from the gracile and cuneate nuclei to the thalamus.

• ipsilateral cranial nerve dysfunction
• contralateral spastic hemiparesis (= paralysis of one side of the body)
• hyperreflexia (= exaggeration of the deep tendon reflexes) and extensor plantar response
• contralateral hemisensory loss
• ipsilateral incoordination

The cisterna magna (or cerebellomedullary cistern) is one of three principal openings in the subarachnoid space between the arachnoid and pia mater layers of the meninges surrounding the brain. The openings are collectively referred to as cisterns. The cisterna magna is located between the cerebellum and the dorsal surface of the medulla oblongata. Cerebrospinal fluid produced in the fourth ventricle drains into the cisterna magna via the lateral apertures and median aperture.

a thalamus
b superior colliculus
c inferior colliculus
d locus coeruleus is a nucleus in the brain stem involved with physiological responses to stress and panic
e vestibular area (lateral to sulcus limitans)
f vagal trigone
g cuneate tubercle (carrying fine touch and proprioceptive information from the upper body (above T6, excepting the face and ear - the information from the face and ear is carried by the primary sensory trigeminal nucleus) to the thalamus and cerebellum via the medial lemniscus)
h gracile tubercle It contains second-order neurons of the dorsal column-medial lemniscus system, which receive inputs from sensory neurons of the dorsal root ganglia and send axons that synapse in the thalamus.
i obex (The obex (from the Latin for barrier) is the point in the human brain at which the fourth ventricle narrows to become the central canal of the spinal cord.The obex occurs in the caudal medulla. The decussating of sensory fibers happens at this point.)
j hypoglossal trigone
k fascial colliculus The facial colliculus is an elevated area located on the dorsal pons. It is formed by motor fibres of the facial nerve
l inferor
m middle
n suoerior cerebellar peduncles
o trochlear nerve
p pineal gland
q cerebellar peduncles

The tectum is a region of the brain, specifically the dorsal part of the mesencephalon (midbrain). T. It is responsible for auditory and visual reflexes.
The tegmentum is a general area within the brainstem. It is located between the ventricular system and distinctive basal or ventral structures at each level. It forms the floor of the midbrain whereas the tectum forms the ceiling.[2] It is a multisynaptic network of neurons that is involved in many unconscious homeostatic and reflexive pathways.

a periaqueductal grey
b grey central matter
c forth ventricle
d emerging csf through midline foramen
e central canal of spinal cord
f spinal cord
g pyramid
h poms
i tegmentum
j cerebral aqueduct
k tectum

The functions of the cerebellum are entirely motor, and operate at an unconscious level. It
controls the maintenance of balance (equilibrium) and influences posture and muscle tone as
well as coordinating movement.

a vermis
b folia
c vallecula
d post. lobe
e primary frissure
f ant lobe
g midbrain

concerned with the maintenance of balance (equilibrium), and has extensive afferent and efferent connections with the vestibular and reticular nuclei of the brainstem via the inferior cerebellar peduncles.

consists of the vermis and adjacent parts of the cerebellar hemispheres - the paravermis, within both the anterior and posterior lobes.
influences muscle tone and posture.
Afferent fibres from muscle, joint and cutaneous receptors  terminate in the ipsilateral paleocerebellum through the inferior and superior cerebellar peduncles.

conveys inconscient proprioceptive information from the body to the cerebellum[1].

proprioceptive information from the body to the cerebellum. It is part of the somatosensory system and runs in parallel with the dorsal spinocerebellar tract. Both these tracts involve two neurons. The ventral spinocerebellar tract will cross to the opposite side of the body then cross again to end in the cerebellum (referred to as a "double cross"), as compared to the dorsal spinocerebellar tract, which does not decussate, or cross sides, at all through its path.

The globose nucleus is one of the deep cerebellar nuclei. It is located medial to the emboliform nucleus and lateral to the fastigial nucleus. This nucleus contains primarily large and small multipolar neurons.
Efferents pass to the deep nuclei of the cerebellum (especially the globose and emboliform), which project in turn via the superior cerebellar peduncle to the contralateral red nucleus of the
midbrain and influence the descending rubrospinal tract

It is the main route for the mediation of voluntary movement. It is responsible for large muscle movement such as the arms and the legs as well as for fine motor control. It facilitates the flexion and inhibits the extension in the upper extremities

The red nucleus is a structure in the rostral midbrain involved in motor coordination.

neocerebellum (muscular coordination, including the trajectory, speed and force of movements.)
paleocerebellum influences muscle tone and posture
archicerebellum balance

gray matter nearest to the middle line at the anterior end of the superior vermis, and immediately over the roof of the fourth ventricle, from which it is separated by a thin layer of white matter.

afferent pathway in neocerebellum consists of pontocerebellar fibres, i.e. neurons originating in the pontine nuclei of the basal portion of the pons projecting across the midline to enter the contralateral
cerebellar hemisphere through the middle cerebellar peduncle. The pontocerebellar neurons
are influenced by widespread regions of the cerebral cortex involved in the planning and execution of movements.
The pontocerebellar neurons themselves project predominantly to the
l

superior cerebellar peduncle,
decussating in the caudal midbrain
projecting to the contralateral ventral lateral thalamus (some by relaying in the red nucleus).

cerebral cortex, particularly the motor cortex of the frontal lobe.
In this way the neocerebellum exerts a coordinating role in movement by  on the motor cortex and its descending corticospinal and corticobulbar pathways.

congenital or acquired condition where the cerebellar tonsils are forced through the foramen magnum, often blocking
the flow of CSF and compressing or stretching the brainstem, lower cranial nerves or inferior
Infants may present with stridor (a high pitched sound of turbulent gas flow in the upper respiratory tract) and swallowing difficulties, older children with upper and progressive lower limb weakness and breathing difficulties.

outer cortex of grey matter, and an inner core of afferent and efferent white matter, the branching projections of which form a tree like pattern – the so-called arbor vitae. Deep within the white matter are buried four pairs of cerebellar nuclei, from medial to lateral;
1. dentate nucleus (with a serrated or toothed appearance in section); the only deep
nucleus easily visible to the naked eye),
2. globose nucleus )
3. emboliform nucleus
4. fastigial nucleus considered part of the archicerebellum.
The globose and emboliform nuclei, lying between the dentate and fastigial, are sometimes
collectively referred to as the interposed nuclei.

grey mater of the cerebral cortex

1. Pyramidal cells 
2. Spiny stellate cells  are excitatory.
3. Smooth stellate cells

a mammary body
b optic tract
c interpedencular fossa
d cerebral peducle
e pons
f pyramid
g loive
h decussation of pyramids
i spinal cord
j spinal acessory nerve (11)
k cranial accesory nerve (11)
l vagus nerve 10
m hypoglossal nerve 12
n glosopharyngeal nerve 9
o vestibuloochlear 8
p nervus intermedius
q facial nerve 7
r abducens (6)
s sensory root
t motor root
u trigeminral nerve
v trochlear nerve 4
w oculomotor nerve 3
x infundibulum
y optic nerve 2

midbrain, pons and medulla
oblongata

remember: dorsal column is for pain and the spinothalamic one for temperature and touch

A premotor cortex
B precentral gyros primary motor cortex
C central sulcus
D postcentral gyros somatosensory cortex
E superior parietal lobule
F intraparietal sulcus
G inferior parietal sulcus
H primary virual center
I auditory associaton cortex (wenickes area)
J primary auditory cetner
K  superior temporl gyros
L lateral frissure
M borcas area
N frontal eye field

basal ganglia
(caudate nucleus, putamen, pallidum, etc.) and thalamus

Areas of cortex at the junction of these parietal, temporal and occiputal lobes are known as
association cortex, and are necessary for multimodal and spatial recognition.

enable storage and retrieval of information processed in
the posterior lobes

frontal lobe is concerned with the organisation of movement (the
primary motor cortex, premotor cortex and supplementary motor areas) and the strategic
guidance of complex motor actions over time (the prefrontal area)

A:premotor cortex
b primary motor cortex precentral gyros
c central sulcus
d somatosensory cotrex postcentral gyros
e parieto occipital sulcus
f visual association cortex
g calcarine sulcus
h primary visual cortex
i parahippocampla gyros
j cingulate gyros+
k cingulate sulcus

has neurons that project to target muscles on the contralateral (opposite) side of the body and control voluntary,skilled (so-called fractionated) movements

Betz cells are pyramidal cell neurons located within the fifth layer of the grey matter in the primary motor cortex

Afferent (incoming) fibres to the primary motor cortex originate principally from the thalamus (the ventral lateral nucleus), which in turn receives input from the dentate nucleus of the
cerebellum and the pallidum  of
the basal ganglia.

Neurons of the premotor cortex produce
less focussed movements than those of the
primary motor cortex, and involve groups of
functionally related muscles. They are
involved in programming of,
and preparation for, movement and in the
control of posture

premotor cortex has short association fibres with which it communicates with the primary motor cortex

afferent fibres to the premotor cortex form the thalamus (ventral anterior nucleus), which in turn receives fibres from the globus pallidus of the basal ganglia and the
substantia nigra of the midbrain.

middle frontal gyrus, controls voluntary conjugate deviation of the eyes (i.e.
scanning movements).

long association (i.e. interlobar)
fibres
Afferent fibres originate principally in the thalamus (mediodorsal and anterior nuclei
It
is involved in  cognition, including faculties of intellect, judgement, prediction and the
planning of behaviour.

• Paroxysmal (i.e. short, frequent) jerking movements in a contralateral limb, known as  simple motor or Jacksonian seizures
• contralateral hemiplegia, with weakness of the face and upper motor neuron signs in the limb
• Broca's aphasia with difficulty producing brief utterances, paraphasia (word errors) and poor
articulation. Word repetition is impaired, but comprehension preserved. Alexia and agraphia
(complete inability to read or write) may present.

- the medial lemniscus - a
brainstem pathway for second order afferent neurons
(conveying information about fine touch and proprioception)
• the spinal lemniscus (coarse touch and pressure) and
spinothalamic tracts (pain and temperature)
• trigeminothalamic tracts (general sensation from the head)

ventral posterior nucleus

receives general sensory information and is responsible for conscious awareness
of the contralateral half of the body (lesions here causes problems at other half of the body)

In the dominant
hemisphere it contributes to language functions.

• paroxysmal attacks of abnormal sensations spreading down the contralateral side of the body (sensory seizures)
• a contralateral hemisensory loss (i.e. loss of feeling on the opposite side of the body) and inferior
visual field loss
• inability to name objects, read, write and/or calculate (technically known as anomia, alexia, agraphia and acalculia, respectively)

• paroxysmal attacks of sensory disturbance affecting the contralateral side of the body (simple
sensory seizures)
• a contralateral hemisensory loss and inferior visual field loss
• spatial disorientation resulting in an inability to copy and construct designs (constructional
apraxia)

-conscious perception of sound, different wavelengths of which are
perceived tonotopically within the cochlear duct. The primary auditory
- afferent fibres from the thalamus (the medial geniculate nucleus), which in turn receives ascending acoustic fibres that have undergone partial decussation (crossing-over) in the brainstem. This
means that acoustic sensation from both ears is represented in each primary auditory cortex,

Wernicke's area, which is necessary for understanding of the spoken word and has i connections with other language areas of the brain (e.g. with Broca's area by the long association fibres of the arcuate fasciculus

semicircular canals of the vestibular system responsible for the sense of balance. The vestibular nerve runs with the cochlear nerve
as the VIIIth cranial (vestibulocochlear) nerve

hippocampus
ssociated with the floor lateral ventricle, deep to the
parahippocampal gyrus
It forms part of the limbic system
associated with long term memory and the emotional aspects of behaviour.

parahypocampal gyros

Near the anterior end of the hippocampus and the anterior end of the lobe (the temporal pole),
grey matter
limbic system
fibres from the olfactory tract (Ist cranial nerve),
and are involved in the conscious appreciation of the sense of smell.

• paroxysmal attacks of unresponsiveness (absences), purposeless behaviour (automatism), olfactory, visual and/or auditory hallucinations, and disturbances of mood
and memory (déjà vu)(complex partial seizures)
• contralateral superior visual field loss
• rapid, fluent speech rendered incomprehensible by word errors (paraphasia). Profound word finding difficulty, impaired repetition of words and profound loss of comprehension (Wernicke’s aphasia)

involved in the understanding of written and spoken language.

optic radiation from the thalamus (the lateral geniculate nucleus), which receives in turn fibres from retinal ganglion cells which are partially decussated at the optic chiasm.

interpretation of images
Unilateral damage to the primary visual cortex causes blindness in the contralateral visual field,
damage to the visual association cortex creates problems with
recognition and interpretation of images.

• paroxysmal visual hallucinations of a simple, unformed nature, e.g. lights or colours
• contralateral visual field loss (contralateral homonymous hemianopia)
- Rare bilateral lesions of the occipital lobe (due to stroke or head injury) may lead to cortical blindness of which the patient is unaware (Anton’s blindness or Anton-Babinski syndrome)
-Bilateral parietooccipital lesions may spare elementary vision, but prevent the recognition or depiction of objects
(apperceptive visual agnosia).

The part of the brain that contains myelinated nerve fibers. The white matter is white because it is the color of myelin, the insulation covering the nerve fibers. The white matter is as opposed to the gray matter (the cortex of the brain which contains nerve cell bodies).

Its function includes relaying sensation, special sense and motor signals to the cerebral cortex, along with the regulation of consciousness, sleep and alertness. The thalamus surrounds the third ventricle. It is the main product of the embryonic diencephalon.

a striatum
b amygdala
c neostratium
d paleostratium
e cudate nucleus
f putamen
g pallidum
h lentiform nucleus

a caudate nucleus
b putamen
c thalamus
d pallidum
e subthAlamic nucleus
f sustantia negra

a motor cortex
b caudate nucleus
c puamen
d thalamus
e and f pallidum medial and lateral
g subthalamic nucleus
h subszantia negra
i Pedunculopontine
nucleus