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Year 2 LCRS Neurology > All of Neuro (1-5) > Flashcards

Flashcards in All of Neuro (1-5) Deck (272)
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1
Q
A
2
Q

What is the process called neurolation

A

It is the embryological formation of the neural tube

3
Q

What is the neural tube?

A

The embryological precursor of the CNS

4
Q

Explain the formation of the neural tube in early development

A
  1. Around Week three:
    • Neral plate develops as part of the ectoderm
  2. Neural folds form from the neural plates, differentiation into neuroepithelium and neural crest cells starts to appear
  3. At around day 25 the neural folds fuse and form the neural tube (neuroepithelium on walls, Neural canal in the middle and neural crest cells attached)
6
Q

What are the characteristics of the neural crest?

How does if further develop?

A

Will form the PNS

Will differentiate into

  • sensory neurons of dorsal roote ganglia
  • Postganglionic autonomic neurons
  • Schwann cells
  • Non-neural derivates e.g. melanocytes
7
Q

What are the characteristics of the neuroepithelium?

How does it undergo further differentiation?

A

Neuroepithelium –> Will form CNS

  • lines the inner walls of the neural tube

It will differentiate into

  • Neuroblasts
    • All neurones with cell bodies in CNS
  • Glioblasts
    • Astrocytes, Oligodendrocytes
  • Ependymal cells
    • Lining ventricles and central canal
9
Q

Explain / Name the Layers of the neural tube

A
10
Q

How does the developing brainstem look like?

What significance does this have in adulthood?

A

Developing brainstem is basically an “unclosed neural tube”

  • explains the medial location of motor and lateral location of sensory devision in brainstem (would be ventral and dorsal in spinal chord)
  • Ventricles start to separate
11
Q

How does the brain look at approx. 4 weeks?

A
12
Q

Explain the proliferation and differentiation of the neuroepithelium and explain the formation of white and grey matter

A
  • Neuropithelium proliferates at the inside of the neural walls
  • cells bodys migrate from ependymal (inside) layer up to form grey matter
  • Fibrous projections start to form white matter
13
Q

What changes between 4th and 5th week in brain development?

A

Pic: 4th Week right, 5th week left

  • Differentiation of forebrain and formation of the telencephalon and diencephalon
  • Differentiation of hindbrain and formation of pons and medually
14
Q

How does the brain develop von Week 5 to Week 8?

A

In week eight

More sturctures are visible:

  • the two cerebral hemispheres develop
  • And the cerebellum develops
15
Q

How are the three flexures in the developing neural tube called?

A
16
Q

Descibe the changes to the neural tube from 4th to 8th Week in regards to the Flexures

A

They start to get more complicated, cervical flexure starts to flex further and give rise to the spinal chord

17
Q

Which factors drive neural development and ependymal differentiation?

A

It is driven by:

Signaling Molecules secreted by surrounding tissue that attrackts, repulses migration and axonal growth

18
Q

Explain the embryological development of the cerebral cortex

A

It happens in Telencephalon

  • radial glia cells (type of astrocyte) form tracts –> neruons migrate up upon the tracts
  • This gives rise to the 6-layered structure of the cortex
20
Q

What kind of developmental disorders can occur in the development of the neural tube/ neural system?

A
21
Q

What is cranioachischisis?

A
22
Q

What is anencephaly?

A
  • often also brain parts missing (e.g. cortex)
  • –> fatal
23
Q

What is encephalocele?

A
24
Q

What is iniencephaly?

A

Developmental disorfer of the upper neural tube

25
Q

What is spina bifta occulata?

A
26
Q

What is a closed spinal dysrphism?

A
27
Q

What is a meningocele?

A

Neural tube defect

28
Q

What is Myelomeningocele?

A
31
Q

What are the embryological synonyms for fore, mid and hindbrain?

A

Forebrain

  • prosencephalon

Midbrain

  • Mesencephalon

Hindbrain

  • Rhombencephalon
36
Q

Which part of the brain makes us human?

A

the cerebral cortex

38
Q

Which factors can account for a developmental disorder of the neural tube ?

A
  • Genetic
  • Environmental
    • Mothers lifestyle
    • diet
    • teatognes (exogenic factos that lead to developmental disorders)
48
Q

Developmental neurobiology: explain how an understanding of developmental neurobiology may help in the treatment of neurological disorders

A

Neural stemm cells:

The brain has neural stemm cells, allowing repair

But it isn’t yet fully understood how this works and how to exploit this in alzheimers or parkinsons (or other degenerative diseases)

49
Q

How many pairs of spinal nerves are there?

How are they classified?

A

31 Pairs

  • 8 Cervical
  • 12 Thoracic
  • 5 Sacral
  • 5 Lumbar
  • 1 Coccyngeal
50
Q

How do nerves leave the vertebra colum?

A

•Nerves leave the vertebral column through intervertebral foramina

51
Q

Where are normal enlargements of the spinal chord found?

Why?

A

Enlargements for innervation of the limbs:

  • Cervical (C3-T1)
  • Lumbar (L1-S3)
52
Q

How do spinal levels and vertebra levels relate to one another?

A

Discrepancy between spinal levels and vertebral levels

  • Vertebra level: Level of the vertebra the spinal nerve emerges from the vertebra colum
  • Spinal level: Level where the spinal segment has its origin
    • –> Vertebra level can be much further down than spinal levels, especially at lumber + sacral region
53
Q

How is the organisation of the meningeines in the spinal chord different from the one in the Brain?

A

In spinal chord

  • ther is space between the Dura Mater and the Bone

–> has a physiological epidural space (relevant for e.g. anestesia)

54
Q

What is the difference between a root and a ramus?

A

Root:

  • e.g. dorsal root + ventral root: carry either sensory or motor information to/from spinal chord

Ramus:

  • Splitting of mixed spinal nerve that either supplies the back (posterior ramus) or the front (anterior ramus)
56
Q
A
57
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A
58
Q
A
59
Q
A
60
Q
A
61
Q
A
62
Q
A
63
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A
64
Q

Name + Function

A

Posterior Colum:

  • Sensory (touch, pain etc.) from ipsilateral limbs
65
Q

Name + Function

A
  • Pain and Temperature from contralateral side to body
  • Motor to ipsilateral anterior spinal horn
  • Proprioception (Gefühl von Selbstbewegung und Körperhaltung) from limbs to cerebellum
66
Q

Name + Function

A

Motor to ipsi and contralateral anterior horn

67
Q

What does the Faciculus gracilis spinal tract controll? Where is it Situatied?

A

It is located in posterior colum:

  • Sensory (touch, vibration , proprioception) from ipsilateral lower limb)
68
Q
A
69
Q

What is the Faciculus Cuneatus?

Where is it situated?

A

Posterior Colum

  • Sentory (touch, vibration etc.) from ipsilateral upper limb
70
Q

Where is the spinocerebellar tract located?

What is its function?

A

Located in the lateral column:

  • conveys proprioception (Gefühl von Selbstbewegung und Körperhaltung) from limbs to cerebellum
71
Q
A
72
Q
A
73
Q
A
74
Q

What is the function of the Lateral Corticospinal tract?

Where is it situated?

A
  • Located at latereal colum
  • Conveys motor infromation to ipsilateral anterior horn (mostly for limb musculature)
75
Q

What it hte function of the Spinothalamic tract?

Where is is located?

A

Conveys Pain and Temperarture from contralateral side of body (crosses when entering)

  • Located in lateral colum (around anterior horn)
76
Q
A
77
Q
A
78
Q

What is the function of the anterior coticospinal tract? Where is it located?

A
  • It is located in the anterior colum
  • Motor to ipsi and contralateral anterior horn (mostly axial musculature)
  • Axial Musculature= muscles that move head, neck, spine and ribcage
79
Q

What is the anterior white commisure?

A

Part of spinal chord where

  • pain and temperature fibres
  • Anteriorcorticospinal tract fibres

cross

81
Q

Explain the route and function of the dorsam colum pathways

A
  • Fasciculus gracilic and Fasciculus Cuneatus
  • Discriminative touch, vibration, proprioception
  • 2nd. neurone crosses over at Medulla
82
Q

Compare the two main sensory pathways (Dorsal colum pathway and spinothalamic tract) in regard to their route to the brain.

A

Spinothalamic tract (pain, temperature)

  • synapses earlier, 2nd. neuron crosses sides when entering (or 2 vertebra up or down the neuron takes via the Lissauer tract)

Dorsal Colum pathways

  • cross over in Medulla (synapse in dorsal column nuclei)
83
Q

Explain the function and route of the corticospinal tract

A

Corticospinal tract

  • Main tract for voluntary movment of limbs and trunk
  • Two motor neuron
  • Devides in the Lateral corticospinal tract
    • major root (about 85%)
    • Decussion in the medulla oblangata
    • target: anterior horn of spinal chord
    • fine movement of ipsilateral limbs (though contralateral to motor cortex)
  • And Anterior corticospinal tract
    • 15 % of corticospinal tract
    • cross over in the spinal level they innervate
    • Then synapse at the anterior horn with the lower motor neuron
    • controls ipsi- and contralateral axial muscles
84
Q

Where is autonomic outflow from the spine?

Which structural components relate to that?

A

Outflow fron grey matter lateral horn

  • PNS= Cranial Nerves III, VII, IX, X + S2-S4
  • SNS= T1-L2
86
Q

How does a refley happen?

A

Sensoring fibres directly go to anterior horn (via the dorsal root) and synapse on motor fibres

–> convey a motor response without going to motor corte

87
Q

What it the Brown Séquad Syndrome?

A

It is a combination of symptoms resulting from a one-sided damage to the spinal chord resulting in

  • Paralysis and loss of proprioception on the ipsilateral side
  • Loss of pain and temperature sensation on contralateral side of lesion
91
Q

What are the neurological termes used for

  • Anterior
  • Posterior
  • Superior
  • Inferior
A

Anterior= Ventral

Posterior = Dorsal

Superior = Rostal

Inferior = Caudal

116
Q

What does decussation mean?

A

The crossing over of nerve fibres

121
Q

Explain the two stages of injury to the lateral corticospinal tract

A

Stage 1. Spinal shock: loss of reflex activity below the lesion, lasting for days or weeks = flaccid paralysis

Stage 2. Return of reflexes: hyperreflexia and/or spasticity = rigid paralysis

122
Q

What is the brainstem?

A

Part of the brain between the cerebrum and the spinal chord (exclusive of the cerebellum)

  • Midbrain
  • Pons
  • Medulla
123
Q

Identify the Pineal Gland

  • What is its function
  • What is its special characteristic
A
  • Only structure on the posterior brainstem which is not bilateral

Endocrine gland producing melatonin —> regulation of day and night rythm

125
Q
A
126
Q

Identify the Dorsal Colums

What is their function?

A

Contains ascending sensory pathways

–> carry tactile sensation and proprioceptive information

127
Q

Where does the Trochlear nerve emerges? What is its function?

A

Cranial nerve IV = trochlear nerve

Motor nerve innervating the superior oblique muscle of the eye

  • intorsion (internal rotation)
  • depression (primarily in the adducted position) and
  • abduction (lateral rotation)

Emerges posterior to the brain stem just below inferior collicolus

128
Q

What is its function?

A

Optic chiasm

  • crossing of optic fibres of the optic nerve
129
Q
A
130
Q

What is its function?

A

Mamillary body

  • part of the diencephalon and limbic system
  • important in recollective memory
131
Q

What is its function?

A

Cerebral peduncle

  • at the front of the midbrain which arise from the front of the pons and contain the large ascending (sensory) and descending (motor) nerve tracts that run to and from the cerebrum from the pons
  • is everything in the midbrain except the tectum
132
Q

What is its function?

A

Occulomotor nerve (III)

  • innervation of extrinsic eye muscle for most movements of the eye + raise eyelid
  • pupillary constriction and adaptiation

third nerve nucleus is located ventral to the cerebral aqueduct

133
Q

What is its function?

A

Trigeminal nerve (V)

  • Face sensation + motor function (chewing)
  • –> largest of the cranial nerves

Emerges at level of the pons

134
Q

What are they?

What are their function?

A

Glossopharyngeal nerve (IX)

  • innervation of toung and pharynx

Vagus (X)

  • PNS
  • motorinnervation pharynx, larynx oesophagus

Accesory (XI)

  • supplies the sternocleidomastoid (rotation of head)
  • and trapezius muscles (shruging of shoulder)
135
Q

What is its function?

A

Medullary pyramids

motor fibers of the corticospinal and corticobulbar tracts –> together: pyramidal tracts

136
Q

What is it?

What is its function?

A

Pyramidal decussation

point at the junction of the medulla and spinal cord where the motor fibers from the medullary pyramids cross the midline. The fibers then continue into the spinal cord primarily as the corticospinal tract.

137
Q

What are they?

What is their function?

A

Abducens (VI)

  • Musculus rectus lateralis innervatio of the eye (abduziert das Auge –> drehbewegung zur Schläfe)

Facial (VII)

  • muscles of facial expression
  • taste from anterior 2/3 of tounge

Vestibulocochlear (VIII)

  • sound and balance information

–> all originate from the upper part of the pons

138
Q

What is its function?

A

Hypoglossal nerve (XII)

  • extrinsic and intrinsic musles of the tounge
140
Q

Identify the Superior and inferior culliculus

What are their fuction?

A

Superior

  • coordination of hand eye movement

Inferior:

  • Survaval function –> auditive relexes
146
Q

Where does GSA, GSE, GVA, GVE nerve fibres develop in the embryonic spinal chord?

A
147
Q

Where do GSA, GSE, GVA, GVE nerve fibres develop in the embryonic rhombencephalon?

A
148
Q

Where is the Special somativ afferent zone in the brainstem located?

Which cranial nerve emerves from this zone?

Where does it emerge?

A

Located Lateral

Vestibulocholear nerve (VIII) emerges from this zone (in pons and medulla)

  • sound and equilibrium
149
Q

Where is the General Somativ afferent zone in the brainstem located?

Which nerve emerges from it?

Where does it emerge?

A

Trigeminal (V)

GSA zone: located in the middle of the (lateral) sensory devision of the brainstem

Three devisions emerge from Midbrain, Pons and Medulla

  • sensation from skin and mucus membranes
150
Q

Where is the General Visceral afferent and special visceral afferent zone in the brainstem located?

Which structures does it contain?

A

It is located most medial of the sensory devision (which is generally latera)

It contains the Solitarium

  • mainly in medulla oblangata
  • sensory nucleus sensing
    • taste, smell
    • GI tract, heart, vessels, lungs
151
Q

Where is the zone containing General Somatic efferent nuclei in the brainstem located?

What emerges from it?

What is its function

A

General somatic efferent

  • eye + tounge movement
  • most medial in brainstem

Via the

  • Occulumotor (III)
    • at midbrain
  • Trochlear (IV)
    • at midbrain
  • Aducens (V)
    • in pons
  • Hypoglossal (XII)
    • in medulla
152
Q

Where is the zone containing Special visceral efferent nerves in the brainstem located?

What emerges from it (where)?

What is its function

A

Special visceral efferent zone

  • medial within motor part (medial)
  • Muscels involved in
    • chewing
    • facial expression
    • swallowing
    • vocal sounds
    • head turning

Trigeminal (motor) (V)

  • Pons

Facial (VII)

  • Pons

Nucleus Ambiguus

  • Medulla
  • contains nerves innervating the sofe palate, pharynx, larynx

Accessory (XI)

  • Cervical spinal chord
153
Q

Where is the zone containing General visceral efferent fibres in the brainstem located?

What emerges from it (and where)?

What is its funciton?

A

General visceral efferent

  • Most lateral within motor part of brainstem (medial)
  • Contains preganglionic parasympathetic fibres

Edinger Westphal nucleus

  • Midbrain
  • PNS nucleus innervating ciliary muscle + iris sphincter mucle

Salivatory nuclei

  • Lower Pons+ Higher medulla

Vagus

  • Medulla
154
Q

What are the distinguishing structural features of the midbrain?

A
  • Mickey mouse shape
  • substantia niagra
  • aqueduct
155
Q

What are the distinguishing structural features of the pons?

A

Most prominent

  • transverse fibres
156
Q

What are the distinguishing structural features of the Medulla?

A
157
Q

What are the structural distinguishing features of the lower medulla?

A
158
Q

What is the lateral medullary syndrome?

A

Infarction of the dorolateral part of the medulla due to occlusion of the

  • vertebral artery
  • or posterior inferir cerebral artery
159
Q

What are the symptoma of the lateral medullary syndrome?

A
  • Vertigo (Schwindel)
  • Ipsilateral cerebellar ataxia (inability to coordinate balance, gait, extremity and eye movements)
  • Ipsilateral loss of pain/thermal sense (face)
  • Horner’s syndrome
  • Hoarseness, difficulty in swallowing
  • Contralateral loss of pain/thermal sense (trunk and limbs)
160
Q

What is Horner’s syndrome

A

Rare combination of

  • miosis (constriction of the pupil),
  • ptosis (drooping of the upper eyelid)
  • and anhidrosis (absence of sweating of the face)

–> caused by damage to the sympathetic nerves of the face.

170
Q

Which type of infromation do general somatic afferent (GSA) nerve fibres carry?

A

General somatic afferent

  • sensation from skin and mucous membranes
171
Q

Which type of infromation do general visceral afferent (GVA) nerve fibres carry?

A

General visceral afferent (GVA)

  • sensation from GI tract, heart vessels and lungs
172
Q

Which type of infromation do special somatic afferent (SSA) nerve fibres carry?

A

Special somativ afferent

  • vision
  • hearing
  • equilibrium
173
Q

Which type of infromation do special visceral afferent nerve fibres carry?

A

Special visceral afferent

  • smell
  • taste
174
Q

Which type of information do general somatic efferent (GSE) nerve fibres carry?

A

General Somativ efferent

  • muscles for eye and tounge movement
175
Q

Which type of information do General visceral efferent (GVE) nerve fibres carry?

A

General visceral efferent

  • preganglionic parasympathetic
176
Q

Which type of information do special visceral efferent nerve fibres carry?

A

Specail visceral efferent

  • muscles involved in chewing
  • facial expression
  • swallowing
  • vocal sounds
  • head turning
192
Q

What is cerebellar ataxia?

A

Ataxia originating in the cerebellum

Characterised by:

inability to coordinate balance, gait, extremity and eye movements

193
Q

For which percent of the body weight and cardiac output does the brain makes up?

A

Only 2% of body weight but

10- 20% of cardiac output

194
Q

Which two major arteries supply the brain with blood?

A
  • Internal carotid artery
  • Vertebral arteries
195
Q

What is the circle of Willis?

A

Anastomosis of arteries supplying the brain

–> allows collater circulation in the cerebral circulation

196
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A
197
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A
198
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A
199
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A
200
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A
201
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A
202
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A
210
Q

Which part of the brain is supplied by the anterior cerebral artery?

A

Medial two thirds of the Cortex

  • Medial prtions of frontal lobes
  • Superior medial parietal lobes
211
Q

Which part of the brain is supplied by the middle cerebral artery?

A

Lateral 2/3 of cortex + forebrain

212
Q

Which part of the brain is supplied by the posterior cerebral artery?

A

The occipital lobe (posterior part)

213
Q

Which symptoms might occur when ther is a blockage to the anterior cerebral artery?

A

Paralysis of

  • contralateral leg (more than arm)
  • face

Disturbance of intelect, executive function and judgement (–>abulia)

Loss of appropirate social behaviour

214
Q

Which symptoms might occur when there is a occlusion of the middle cerebral artery?

A

“Classic stroke”—

  • Contralateral hemiplegia (=hemiparesis): arm rather than leg
  • —Contralateral hemisensory (=altered sensation) deficits
  • —Hemianopia (optical disturbance (blurred/blindness)
  • —Aphasia (L sided lesion) (loss of speach)
216
Q

What is hemianopia?

A

Visual field loss in a vertical line

218
Q

What is Broca’s aphasia?

A

It is expressice loss of speach

due to damage to the broca region

219
Q

What is Wernicke’s aphasia?

A

Receptive aphasia

  • loss of understnading of speech

–> due to damage to the Wernicke region of the brain

220
Q

How does a paitent with blockafe of the posterior cerebral artery might present?

A

—Visual deficits

  • homonymous hemianopia (hemianopic visual field loss on the same side of both eyes)
  • visual agnosia (impaired visual perception)
221
Q

What is a Lacunar Infarct?

A
  • —Lacune is a small cavity formed by tissue loss due to former strokes
  • —Appear in deep structures as a result of small vessel occlusion
  • —Deficit is dependent on anatomical location
  • Main risk factor: —Hypertension
222
Q

Summarise the overall venous drainage of the brain

A

—Cerebral veins

—–> Venous sinuses (in subarachidonic space) –>

— –> Dura mater

—Internal jugular vein

223
Q

What is a —Cerebrovascular accident (CVA)?

A

A Stroke

rapidly developing focal disturbance of brain function of presumed vascular origin and of >24 hours duration

–> 85% infarction, 15% hemmorage

224
Q

Explain the organisation of the dura mater in relation to the cerebral sinuses?

A

Dura surrounds the sinuses

225
Q

What is a Transient Ischaemic Attack (TIA)?

A

rapidly developing focal disturbance of brain function of presumed vascular origin that resolves completely within 24 hours

–> warning sign: patients are at hight risk of getting a stroke!

226
Q

Which symptoms would you expect with and occlusion of the anterior cerebral artery?

A

Supplies part of motor cortex to legs:

  • paralysis/weakness in contralateral leg
  • loss of sensation in contralateral leg
  • Abulia –> no motivation
  • inability to initiate the process of walking (gait appraxia)
  • urinary incontinence
227
Q

Where would you suspect someone to have a leasion if one presents with following symptoms:

  • paralysis/weakness in contralateral leg
  • loss of sensation in contralateral leg
  • Abulia –> no motivation
  • inability to initiate the process of walking (gait appraxia)
  • urinary incontinence
A

In the anterior cerebral artery

228
Q

What is an infarction?

A

—Degenerative changes which occur in tissue following occlusion of an artery

229
Q

What is cerebral ischemia?

A

—Lack of sufficient blood supply to nervous tissue resulting in permanent damage if blood flow is not restored quickly

—

— hypoxia/anoxia

230
Q

What are posiible causes for an occlusion

A
  • Thrombus (blood cloth at site of formation)
  • Embolus (any other substance or other blood cloth formed in another place)
231
Q

What are the main risk factors for stroke?

A
  • Age
  • Hypertension
  • Cardiac disease
  • Smoking
  • Diabetes mellitus
234
Q

What is a Berry aneurism?

What does it cause?

A

It is a saccular aneurism in the brain

  • most common cause for sub-arachnoid haemorrhage
238
Q

What is hemiplegia?

A

Hemiparesis

(half sided paralysis)

240
Q

What is Aphasia

A

Loss of speach (can also be eiter efferent (understanding) or afferent (speaking))

245
Q

What are the characteristice of a subarachnoid hemorrhage?

A

Usually ruptured aneurysm

  • Rupture can be due to trauma
  • or spontaneous
246
Q

What are the characteristics of a intercerebral hemorrhage?

A

Usually spontaneous

  • closely linked to hypertension
248
Q

Compare a subdural vs. an extradural (epidural) haematoma

A

Subdural:

  • venous
  • slow
  • can be traumatic or spontaneous (more common in eldrely)

Extradural

  • arterial
  • quicker
  • usually traumatic (more common in young patients)
251
Q

Which symptoms would a patient present with when having an occklusion in the basilar artery?

A

Present with locked-in syndrome

252
Q

Which part of the brain dos the middle cerebral artery supply?

A
  • A lot of the lateral surface of the hemisphere
  • (location of Broca’s area i.e. language expression)
  • Inferior division supplies lateral temporal lobe (location of Wernicke’s area i.e. language comprehension)
  • Deep branches supply the basal ganglia as well as the internal capsule
253
Q

Which symptoms might someone present when there is an occlusion of the middle cerebral artery?

A
  • Paralysis + sensory loss of contralateral face and arm
  • Aphasia (dependant of side of brain if Broca of Wernicke) –> usually left
  • contralateral neglect syndrome
  • Contralateral homonymous hemianopsia is often present
254
Q

When someone presents with following symptoms: Where would you supect a leasion to be?

  • Paralysis + sensory loss of contralateral face and arm
  • Aphasia (dependant of side of brain if Broca of Wernicke) –> usually left
  • contralateral neglect syndrome
  • Contralateral homonymous hemianopsia is often present
A

Middle cerebral artery

255
Q

When someone is haveing an occulusion in the posterior cerebral artery, what do you expect the symptoms to be?

A

Supplies the: Occipital lobe, Basal ganglia in temporal lobe, Thalamus, lateral+3rd ventricle

  • Contralateral loss of pain and temperature sensations.
  • Visual field defects (contralateral hemianopia with macular sparing).
  • Prosopagnosia –> no recognition of faces
  • Ipsilateral deficits of oculomotor nerve,
  • Contralateral deficits of facial nerve (only lower face, upper face receives bilateral input), vagus nerve and hypoglossal nerve
256
Q

Someone presenting with following symptoms:

Where do you expect the leasion to be?

  • Contralateral loss of pain and temperature sensations.
  • Visual field defects (contralateral hemianopia with macular sparing).
  • Prosopagnosia –> no recognition of faces
  • Ipsilateral deficits of oculomotor nerve,
  • Contralateral deficits of facial nerve (only lower face, upper face receives bilateral input), vagus nerve and hypoglossal nerve
A

Posterior cerebral artery

257
Q

What happens after a few secounds after loss of blood flow to the brain and after a few minutes?

A
  • After ca. 4 secounds: unconciousness
  • After a few minutes: irreversible brain damage
258
Q

What is a Syncope?

A

Syncope= fainting

–> Result of a temporary reduction or disrubtion of blood flow to the brain?

259
Q

What are normal blood glucose levels?

Which level of blood glucose is potentially fatal?

A

Normal levels: 4-6mM

if it falls below 2mM:

  • can result in unconciousness, coma, death
260
Q

Which two mechanisms regulate cerebral blood flow?

A

Autoregulation of blood flow

  • via contraction/dialaiton of cerebral arteries, arterioles to maintain even blood flow

Local regulation of blood flow via

  • neural control (e.g. SNS/PNS)
  • chemical control (waste products)
261
Q

Explain the autoregulation of total cerebral blood flow

A

Autoregulation between 60-160 mmHg MAP

  • via stretch-senstitive cerebral vasculature:
    • Contracts at high pressures, relaxes at low BP

Above or below the MAP range it can lead to too little blood flow to brain –> fainting or too much leading to a rise in intracranial pressure (dangerous)

263
Q

Which two control mechanism determine local autoregulation of the brain?

A

Local mechanisms influenced by local brain activity and need for Oxygen and nutrients

There are

  • Neural control mechanisms
  • and Chemical control mechanisms
264
Q

Which local neural control mechanisms are ther?

How important are they?

A

4 possible mechanisms

  • SNS stimmulation to main cerebral arterys
    • vasoconstriction, normally only at hight blood pressure
  • PNS/Facial nerve stimmulaiton
    • ​​slight vasodilation
  • Central cortical neuronnes
    • releasing vasoconstrictive neurotransmitters (e.g. adrenaline)
  • Dopaminergic neruones
    • vasoconstriction (local effect, may contribute to diversion of blood flow to areas with high activity)

Overall: Neural control is not well defined and importance is uncertain!

265
Q

Explain how CO2 influcences local blood flow to brain tissue

A

CO2 is produced as metabolism product:

  • diffuses into Vascular Smooth Muscle
  • Carbonic anhydrase: produces H+
  • causes relaxation of SM

–> vasodilaiton –> increased blood flow

266
Q

How do choroid plexi produce CSF?

A

They filtre the blood plasma and make it the composition the CSF has

267
Q

Which chemical factors influence local blood flow to brain tissue?

Which effect do they have?

A
  • CO2
  • pH
  • NO
  • K+
  • Adenosine
  • Anoxia
  • Other e.g. histmines, prostaglandines etc

–> All have a vasodilatora effect on blood flow! (Are waste products –> when high activity–> more waste products –> more blood flow)

268
Q

What are pial vessels?

What do they give rise to?

A

Blood vessels on the surface of the brain, surrounded by CSF

They give rise to smaller arterys that eventually penetrate the brain tissue

269
Q

How far is the maximal distance between a neuron and a blood vessel?

A

Maximal 100µm (one cell about 20)

–> Very dense capillary network!

270
Q

Which structural componenets contribute to the blood brain barrier?

A
  1. Extensive tight junctions at endothelial cell-cell contacts
  2. Pericytes (cells associated with capillaries) densly cover capillaries in CNS
  3. Astrocyte processes cover capillaries
272
Q

What are circumventricular organs?

A

Orangs, where it is neccessary for the BBB to be leaky, or highly permeable

–> e.g. Median eminence in the Pituitary

273
Q

How is the increased leakyness of the (fenestrated) capillaries in circuventricular organs compensated?

A

The ventricular ependymal lining close to these areas can be much tighter than in other areas, limiting the exchange between them and the CSF

275
Q

Explain the importance of the BBB in pharmcokinetics at the example of parkinson treatment via dopamine increase

A

Question: Do you want the medication to cross the BBB?

In Parkinson YES!

–> Additional L-Dopa is given (can cross BBB), which is converted to Dopamine

But most of it is converted periopherally where you would not need the additional dopamine so:

coadministration with DOPA decarboxylase inbibitor that cannot cross the BBB

276
Q

What is the function of the Blood-brain barrier?

A

Neurones are highly sensitive to environmental factors

  • CNS needs to be protected from fluctuation of the blood/body

Homeostasis is key!

280
Q

Which substances can cross the blood brain barrier?

A

Lipohilic molecules can cross membranes of cells and therefore blood brain barriers

  • Hydrophilic molecules require special transport mechanisms
283
Q

Why is sometimes an increased leakyness of capillaries required in the brain?

A

Need to communicate with outside world:

  • the posterior pituitary and median eminence secrete hormones
  • the area postrema samples the plasma for toxins and will induce vomiting
  • others are involved in sensing electrolytes and regulate water intake.
284
Q

What happens after a few secounds after loss of blood flow to the brain and after a few minutes?

A
  • After ca. 4 secounds: unconciousness
  • After a few minutes: irreversible brain damage
285
Q

What is a Syncope?

A

Syncope= fainting

–> Result of a temporary reduction or disrubtion of blood flow to the brain?

286
Q

What are normal blood glucose levels?

Which level of blood glucose is potentially fatal?

A

Normal levels: 4-6mM

if it falls below 2mM:

  • can result in unconciousness, coma, death
287
Q

Which two mechanisms regulate cerebral blood flow?

A

Autoregulation of blood flow

  • via contraction/dialaiton of cerebral arteries, arterioles to maintain even blood flow

Local regulation of blood flow via

  • neural control (e.g. SNS/PNS)
  • chemical control (waste products)
288
Q

Explain the autoregulation of total cerebral blood flow

A

Autoregulation between 60-160 mmHg MAP

  • via stretch-senstitive cerebral vasculature:
    • Contracts at high pressures, relaxes at low BP

Above or below the MAP range it can lead to too little blood flow to brain –> fainting or too much leading to a rise in intracranial pressure (dangerous)

290
Q

Which two control mechanism determine local autoregulation of the brain?

A

Local mechanisms influenced by local brain activity and need for Oxygen and nutrients

There are

  • Neural control mechanisms
  • and Chemical control mechanisms
291
Q

Which local neural control mechanisms are ther?

How important are they?

A

4 possible mechanisms

  • SNS stimmulation to main cerebral arterys
    • vasoconstriction, normally only at hight blood pressure
  • PNS/Facial nerve stimmulaiton
    • ​​slight vasodilation
  • Central cortical neuronnes
    • releasing vasoconstrictive neurotransmitters (e.g. adrenaline)
  • Dopaminergic neruones
    • vasoconstriction (local effect, may contribute to diversion of blood flow to areas with high activity)

Overall: Neural control is not well defined and importance is uncertain!

292
Q

Explain how CO2 influcences local blood flow to brain tissue

A

CO2 is produced as metabolism product:

  • diffuses into Vascular Smooth Muscle
  • Carbonic anhydrase: produces H+
  • causes relaxation of SM

–> vasodilaiton –> increased blood flow

293
Q

How do choroid plexi produce CSF?

A

They filtre the blood plasma and make it the composition the CSF has

294
Q

Which chemical factors influence local blood flow to brain tissue?

Which effect do they have?

A
  • CO2
  • pH
  • NO
  • K+
  • Adenosine
  • Anoxia
  • Other e.g. histmines, prostaglandines etc

–> All have a vasodilatora effect on blood flow! (Are waste products –> when high activity–> more waste products –> more blood flow)

295
Q

What are pial vessels?

What do they give rise to?

A

Blood vessels on the surface of the brain, surrounded by CSF

They give rise to smaller arterys that eventually penetrate the brain tissue

296
Q

How far is the maximal distance between a neuron and a blood vessel?

A

Maximal 100µm (one cell about 20)

–> Very dense capillary network!

297
Q

Which structural componenets contribute to the blood brain barrier?

A
  1. Extensive tight junctions at endothelial cell-cell contacts
  2. Pericytes (cells associated with capillaries) densly cover capillaries in CNS
  3. Astrocyte processes cover capillaries
299
Q

What are circumventricular organs?

A

Orangs, where it is neccessary for the BBB to be leaky, or highly permeable

–> e.g. Median eminence in the Pituitary

300
Q

How is the increased leakyness of the (fenestrated) capillaries in circuventricular organs compensated?

A

The ventricular ependymal lining close to these areas can be much tighter than in other areas, limiting the exchange between them and the CSF

302
Q

Explain the importance of the BBB in pharmcokinetics at the example of parkinson treatment via dopamine increase

A

Question: Do you want the medication to cross the BBB?

In Parkinson YES!

–> Additional L-Dopa is given (can cross BBB), which is converted to Dopamine

But most of it is converted periopherally where you would not need the additional dopamine so:

coadministration with DOPA decarboxylase inbibitor that cannot cross the BBB

303
Q

What is the function of the Blood-brain barrier?

A

Neurones are highly sensitive to environmental factors

  • CNS needs to be protected from fluctuation of the blood/body

Homeostasis is key!

307
Q

Which substances can cross the blood brain barrier?

A

Lipohilic molecules can cross membranes of cells and therefore blood brain barriers

  • Hydrophilic molecules require special transport mechanisms
310
Q

Why is sometimes an increased leakyness of capillaries required in the brain?

A

Need to communicate with outside world:

  • the posterior pituitary and median eminence secrete hormones
  • the area postrema samples the plasma for toxins and will induce vomiting
  • others are involved in sensing electrolytes and regulate water intake.
311
Q

What is the diencephalon?

Where is it located?

A

Diencephalon= Thalamus, Subthalamus and Hypothalamus

Sourrounds 3rd ventricle in middle of brain

312
Q

What is the thalamus?

Where is is located?

A

Thalamus = part of the brain (diencephalon)

Located both sides of 3rd ventrcle

313
Q

Explain the location of the thalamus in regards to the lateral ventricles

A

It sits ventral to the lateral ventricles

314
Q

How is the thalamus organised?

How can it be sub-devided?

A

The thalamus is organised in different discrete Nuclei

–> accumulation of cells bodies with similar function and connections

316
Q

Explain the role of the thalamus in the somatosensory pathway

(And explain the whole pathway)

A

Somatosensory: Conveys vibration, proprioception, touch infromation to brain

  1. st. order neuron (in dorsal ganglion): sensory information to dorsal column of ipsilateral side
  2. (Same neuron) travels up to medulla
  3. 2nd. order neuron crosses over in medulla to contralateral side
  4. This neuron synapses in Ventral posterior lateral nucleus in thalamus
  5. 3rd. order neuron to primary somatosensory cortex
317
Q

In which thalamic nucleus do neurons from the the somatosensory pathway synapse?

A

In the ventral posterior lateral nucles (VPL)

318
Q

What is the role of the ventral posterior lateral nucleus in the thalamus?

A

Synapse point for the Somatosensory pahtway

319
Q

What is the role of the intralaminar nuclei in the thalamus?

A

Project to various places of the brain

e.g. amygdalla, hippocampus and basal ganglia

–> associated with limbic system and basal ganglia

–> usually excitory

323
Q

What are the functions of the thalamus?

A

Relay centre of the brain

  • e.g. for cortical sensory pathways
  • –> Involved in all sensory systems (except olfactory)

Can be inhibitory and exitory

325
Q

Where is the hypothalamus located?

A

(Green part) –> Forms the walls and floor of 3rd ventricle

326
Q

How does the hypothalamus look like?

A
328
Q

What is the function of the paraventricular nucleus?

Where is is located?

A

It is part of the hypothalamus

Two type of cells with different functions

  1. Parvocellular cells (small cells)
    • into spinal chord
    • out (via autonomic system) to vasculature, heart, kidney etc.
  2. Magnocellular cells (large cells)
    • rather secretors
    • secrete VP and Oxytocin in Neurohypophysis
  3. Also incolved in feeding behaviour
  • leasions can cause feeding behavioral disorders
  • it recieves information/ input from other cells involved in feeding bahaviour
329
Q

Where is the Suprachisamatic nucleus located?

A

In the hypothalamus above the optic chiasm

332
Q

What is the function of the reticular nucleus in the thalamus?

A

Like capsule around thalamus (outer layering of thalamus)

–> GABA neurons (inhibitory)

Connect with othe thalamic pathways (and not with other strcutures of the brain) : interregulation of thalamus

333
Q

Which role do the interalaminar nuclei play in disease?

A

Loss of neurons in this region associated with progressive supranuclear palsy* and Parkinson’s disease

–> Progressive degenerative diseases

334
Q

What is the reticular formation?

A

Interconnected pathways within the brainstm

  • particular anatomy of this area is not known

but it has:

  • ascending projections to forebrain called
    • Ascending reticular activating system (ARAS)

(also has descending fibres giving rise to the reticulspinal tracts)

335
Q

What is the function of the ascending reticular activating system?

A

It is the system (ascenging fibres from reticular formation) that makes us concious/aroused

  • Degrees of wakefulness depend on ARAS activity (increased activity = increased wakefulness
336
Q

Explain relationship between intralaminar nuclei, reticular nucleus and reticular formation

A

•Both intralaminar and reticular nucleus receive inputs from ARAS (brainstem to thalamus input)

339
Q

What are the functions of the Hypothalamus?

A

It has many discrete nuclei with differenct functions

  • they are mainly ipsilateral connected with other neurones
  • direct connections to autonomic nervous system
  • Endocrine function
  • control of behaviour (e.g. feeding)

+ 4F’s

  1. Fighting
  2. Fleeing
  3. Feeding
  4. Mating
342
Q

Explain the funciton of the Suprachiasmatic nucles

A

Part of the hpypothalamus

  • involved in Sleep-wake cycle
  1. Controlls autonomic outflow (via Paraventricular nucleus)
  2. Connection to the pineal gland –> Melatonin secretion
343
Q

What might damage to the suprachiasmativ nucleus lead to?

A

It may lead to a disrupted sleep-wake cycle

344
Q

What is the diencephalon?

Where is it located?

A

Diencephalon= Thalamus, Subthalamus and Hypothalamus

Sourrounds 3rd ventricle in middle of brain

345
Q

What is the thalamus?

Where is is located?

A

Thalamus = part of the brain (diencephalon)

Located both sides of 3rd ventrcle

346
Q

Explain the location of the thalamus in regards to the lateral ventricles

A

It sits ventral to the lateral ventricles

347
Q

How is the thalamus organised?

How can it be sub-devided?

A

The thalamus is organised in different discrete Nuclei

–> accumulation of cells bodies with similar function and connections

349
Q

Explain the role of the thalamus in the somatosensory pathway

(And explain the whole pathway)

A

Somatosensory: Conveys vibration, proprioception, touch infromation to brain

  1. st. order neuron (in dorsal ganglion): sensory information to dorsal column of ipsilateral side
  2. (Same neuron) travels up to medulla
  3. 2nd. order neuron crosses over in medulla to contralateral side
  4. This neuron synapses in Ventral posterior lateral nucleus in thalamus
  5. 3rd. order neuron to primary somatosensory cortex
350
Q

In which thalamic nucleus do neurons from the the somatosensory pathway synapse?

A

In the ventral posterior lateral nucles (VPL)

351
Q

What is the role of the ventral posterior lateral nucleus in the thalamus?

A

Synapse point for the Somatosensory pahtway

352
Q

What is the role of the intralaminar nuclei in the thalamus?

A

Project to various places of the brain

e.g. amygdalla, hippocampus and basal ganglia

–> associated with limbic system and basal ganglia

–> usually excitory

356
Q

What are the functions of the thalamus?

A

Relay centre of the brain

  • e.g. for cortical sensory pathways
  • –> Involved in all sensory systems (except olfactory)

Can be inhibitory and exitory

358
Q

Where is the hypothalamus located?

A

(Green part) –> Forms the walls and floor of 3rd ventricle

359
Q

How does the hypothalamus look like?

A
361
Q

What is the function of the paraventricular nucleus?

Where is is located?

A

It is part of the hypothalamus

Two type of cells with different functions

  1. Parvocellular cells (small cells)
    • into spinal chord
    • out (via autonomic system) to vasculature, heart, kidney etc.
  2. Magnocellular cells (large cells)
    • rather secretors
    • secrete VP and Oxytocin in Neurohypophysis
  3. Also incolved in feeding behaviour
  • leasions can cause feeding behavioral disorders
  • it recieves information/ input from other cells involved in feeding bahaviour
362
Q

Where is the Suprachisamatic nucleus located?

A

In the hypothalamus above the optic chiasm

365
Q

What is the function of the reticular nucleus in the thalamus?

A

Like capsule around thalamus (outer layering of thalamus)

–> GABA neurons (inhibitory)

Connect with othe thalamic pathways (and not with other strcutures of the brain) : interregulation of thalamus

366
Q

Which role do the interalaminar nuclei play in disease?

A

Loss of neurons in this region associated with progressive supranuclear palsy* and Parkinson’s disease

–> Progressive degenerative diseases

367
Q

What is the reticular formation?

A

Interconnected pathways within the brainstm

  • particular anatomy of this area is not known

but it has:

  • ascending projections to forebrain called
    • Ascending reticular activating system (ARAS)

(also has descending fibres giving rise to the reticulspinal tracts)

368
Q

What is the function of the ascending reticular activating system?

A

It is the system (ascenging fibres from reticular formation) that makes us concious/aroused

  • Degrees of wakefulness depend on ARAS activity (increased activity = increased wakefulness
369
Q

Explain relationship between intralaminar nuclei, reticular nucleus and reticular formation

A

•Both intralaminar and reticular nucleus receive inputs from ARAS (brainstem to thalamus input)

372
Q

What are the functions of the Hypothalamus?

A

It has many discrete nuclei with differenct functions

  • they are mainly ipsilateral connected with other neurones
  • direct connections to autonomic nervous system
  • Endocrine function
  • control of behaviour (e.g. feeding)

+ 4F’s

  1. Fighting
  2. Fleeing
  3. Feeding
  4. Mating
375
Q

Explain the funciton of the Suprachiasmatic nucles

A

Part of the hpypothalamus

  • involved in Sleep-wake cycle
  1. Controlls autonomic outflow (via Paraventricular nucleus)
  2. Connection to the pineal gland –> Melatonin secretion
376
Q

What might damage to the suprachiasmativ nucleus lead to?

A

It may lead to a disrupted sleep-wake cycle

377
Q

What is the diencephalon?

Where is it located?

A

Diencephalon= Thalamus, Subthalamus and Hypothalamus

Sourrounds 3rd ventricle in middle of brain

378
Q

What is the thalamus?

Where is is located?

A

Thalamus = part of the brain (diencephalon)

Located both sides of 3rd ventrcle

379
Q

Explain the location of the thalamus in regards to the lateral ventricles

A

It sits ventral to the lateral ventricles

380
Q

How is the thalamus organised?

How can it be sub-devided?

A

The thalamus is organised in different discrete Nuclei

–> accumulation of cells bodies with similar function and connections

382
Q

Explain the role of the thalamus in the somatosensory pathway

(And explain the whole pathway)

A

Somatosensory: Conveys vibration, proprioception, touch infromation to brain

  1. st. order neuron (in dorsal ganglion): sensory information to dorsal column of ipsilateral side
  2. (Same neuron) travels up to medulla
  3. 2nd. order neuron crosses over in medulla to contralateral side
  4. This neuron synapses in Ventral posterior lateral nucleus in thalamus
  5. 3rd. order neuron to primary somatosensory cortex
383
Q

In which thalamic nucleus do neurons from the the somatosensory pathway synapse?

A

In the ventral posterior lateral nucles (VPL)

384
Q

What is the role of the ventral posterior lateral nucleus in the thalamus?

A

Synapse point for the Somatosensory pahtway

385
Q

What is the role of the intralaminar nuclei in the thalamus?

A

Project to various places of the brain

e.g. amygdalla, hippocampus and basal ganglia

–> associated with limbic system and basal ganglia

–> usually excitory

389
Q

What are the functions of the thalamus?

A

Relay centre of the brain

  • e.g. for cortical sensory pathways
  • –> Involved in all sensory systems (except olfactory)

Can be inhibitory and exitory

391
Q

Where is the hypothalamus located?

A

(Green part) –> Forms the walls and floor of 3rd ventricle

392
Q

How does the hypothalamus look like?

A
394
Q

What is the function of the paraventricular nucleus?

Where is is located?

A

It is part of the hypothalamus

Two type of cells with different functions

  1. Parvocellular cells (small cells)
    • into spinal chord
    • out (via autonomic system) to vasculature, heart, kidney etc.
  2. Magnocellular cells (large cells)
    • rather secretors
    • secrete VP and Oxytocin in Neurohypophysis
  3. Also incolved in feeding behaviour
  • leasions can cause feeding behavioral disorders
  • it recieves information/ input from other cells involved in feeding bahaviour
395
Q

Where is the Suprachisamatic nucleus located?

A

In the hypothalamus above the optic chiasm

398
Q

What is the function of the reticular nucleus in the thalamus?

A

Like capsule around thalamus (outer layering of thalamus)

–> GABA neurons (inhibitory)

Connect with othe thalamic pathways (and not with other strcutures of the brain) : interregulation of thalamus

399
Q

Which role do the interalaminar nuclei play in disease?

A

Loss of neurons in this region associated with progressive supranuclear palsy* and Parkinson’s disease

–> Progressive degenerative diseases

400
Q

What is the reticular formation?

A

Interconnected pathways within the brainstm

  • particular anatomy of this area is not known

but it has:

  • ascending projections to forebrain called
    • Ascending reticular activating system (ARAS)

(also has descending fibres giving rise to the reticulspinal tracts)

401
Q

What is the function of the ascending reticular activating system?

A

It is the system (ascenging fibres from reticular formation) that makes us concious/aroused

  • Degrees of wakefulness depend on ARAS activity (increased activity = increased wakefulness
402
Q

Explain relationship between intralaminar nuclei, reticular nucleus and reticular formation

A

•Both intralaminar and reticular nucleus receive inputs from ARAS (brainstem to thalamus input)

405
Q

What are the functions of the Hypothalamus?

A

It has many discrete nuclei with differenct functions

  • they are mainly ipsilateral connected with other neurones
  • direct connections to autonomic nervous system
  • Endocrine function
  • control of behaviour (e.g. feeding)

+ 4F’s

  1. Fighting
  2. Fleeing
  3. Feeding
  4. Mating
408
Q

Explain the funciton of the Suprachiasmatic nucles

A

Part of the hpypothalamus

  • involved in Sleep-wake cycle
  1. Controlls autonomic outflow (via Paraventricular nucleus)
  2. Connection to the pineal gland –> Melatonin secretion
409
Q

What might damage to the suprachiasmativ nucleus lead to?

A

It may lead to a disrupted sleep-wake cycle

410
Q

What is the diencephalon?

Where is it located?

A

Diencephalon= Thalamus, Subthalamus and Hypothalamus

Sourrounds 3rd ventricle in middle of brain

411
Q

What is the thalamus?

Where is is located?

A

Thalamus = part of the brain (diencephalon)

Located both sides of 3rd ventrcle

412
Q

Explain the location of the thalamus in regards to the lateral ventricles

A

It sits ventral to the lateral ventricles

413
Q

How is the thalamus organised?

How can it be sub-devided?

A

The thalamus is organised in different discrete Nuclei

–> accumulation of cells bodies with similar function and connections

415
Q

Explain the role of the thalamus in the somatosensory pathway

(And explain the whole pathway)

A

Somatosensory: Conveys vibration, proprioception, touch infromation to brain

  1. st. order neuron (in dorsal ganglion): sensory information to dorsal column of ipsilateral side
  2. (Same neuron) travels up to medulla
  3. 2nd. order neuron crosses over in medulla to contralateral side
  4. This neuron synapses in Ventral posterior lateral nucleus in thalamus
  5. 3rd. order neuron to primary somatosensory cortex
416
Q

In which thalamic nucleus do neurons from the the somatosensory pathway synapse?

A

In the ventral posterior lateral nucles (VPL)

417
Q

What is the role of the ventral posterior lateral nucleus in the thalamus?

A

Synapse point for the Somatosensory pahtway

418
Q

What is the role of the intralaminar nuclei in the thalamus?

A

Project to various places of the brain

e.g. amygdalla, hippocampus and basal ganglia

–> associated with limbic system and basal ganglia

–> usually excitory

422
Q

What are the functions of the thalamus?

A

Relay centre of the brain

  • e.g. for cortical sensory pathways
  • –> Involved in all sensory systems (except olfactory)

Can be inhibitory and exitory

424
Q

Where is the hypothalamus located?

A

(Green part) –> Forms the walls and floor of 3rd ventricle

425
Q

How does the hypothalamus look like?

A
427
Q

What is the function of the paraventricular nucleus?

Where is is located?

A

It is part of the hypothalamus

Two type of cells with different functions

  1. Parvocellular cells (small cells)
    • into spinal chord
    • out (via autonomic system) to vasculature, heart, kidney etc.
  2. Magnocellular cells (large cells)
    • rather secretors
    • secrete VP and Oxytocin in Neurohypophysis
  3. Also incolved in feeding behaviour
  • leasions can cause feeding behavioral disorders
  • it recieves information/ input from other cells involved in feeding bahaviour
428
Q

Where is the Suprachisamatic nucleus located?

A

In the hypothalamus above the optic chiasm

431
Q

What is the function of the reticular nucleus in the thalamus?

A

Like capsule around thalamus (outer layering of thalamus)

–> GABA neurons (inhibitory)

Connect with othe thalamic pathways (and not with other strcutures of the brain) : interregulation of thalamus

432
Q

Which role do the interalaminar nuclei play in disease?

A

Loss of neurons in this region associated with progressive supranuclear palsy* and Parkinson’s disease

–> Progressive degenerative diseases

433
Q

What is the reticular formation?

A

Interconnected pathways within the brainstm

  • particular anatomy of this area is not known

but it has:

  • ascending projections to forebrain called
    • Ascending reticular activating system (ARAS)

(also has descending fibres giving rise to the reticulspinal tracts)

434
Q

What is the function of the ascending reticular activating system?

A

It is the system (ascenging fibres from reticular formation) that makes us concious/aroused

  • Degrees of wakefulness depend on ARAS activity (increased activity = increased wakefulness
435
Q

Explain relationship between intralaminar nuclei, reticular nucleus and reticular formation

A

•Both intralaminar and reticular nucleus receive inputs from ARAS (brainstem to thalamus input)

438
Q

What are the functions of the Hypothalamus?

A

It has many discrete nuclei with differenct functions

  • they are mainly ipsilateral connected with other neurones
  • direct connections to autonomic nervous system
  • Endocrine function
  • control of behaviour (e.g. feeding)

+ 4F’s

  1. Fighting
  2. Fleeing
  3. Feeding
  4. Mating
441
Q

Explain the funciton of the Suprachiasmatic nucles

A

Part of the hpypothalamus

  • involved in Sleep-wake cycle
  1. Controlls autonomic outflow (via Paraventricular nucleus)
  2. Connection to the pineal gland –> Melatonin secretion
442
Q

What might damage to the suprachiasmativ nucleus lead to?

A

It may lead to a disrupted sleep-wake cycle