Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neurology > Principles of Forebrain and Brainstem Disease > Flashcards

Principles of Forebrain and Brainstem Disease Flashcards

1
Q

What is the mesencephalon?

A

Midbrain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the metencephalon?

A

Pons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the myeloencephalon?

A

Medulla oblongata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the rhomboencephalon?

A

Pons (metencephalon) and medulla oblongata (myeloencephalon)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Name the cranial nerves located in

  1. Midbrain
  2. Pons
  3. Medulla oblongata
A
  1. Occulomotor (III) and trochlear (IV)
  2. Trigeminal (V)
  3. Rest (except 1+2)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the roles of the olfactory bulbs/tracts?

A 
Perception of smell
Limbic system (instinct/mood)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which CN are associated with the olfactory bulbs/tracts?

A

Olfactory (CNI)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Outline the pathway of the olfactory nerve…

A

Cell bodies in the nasal epithelium –> Cribriform plate of the ethmoid bone –> Olfactory bulbs –> Olfactory tracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the roles of the temporal lobes of the telencephalon?

A

Auditory area

Vestibular conscious perception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the roles of the frontal lobes of the telencephalon?

A

Motor - corticospinal and corticonuclear tracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the roles of the parietal lobes of the telencephalon?

A

Sensory-motor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the roles of the occipital lobes of the telencephalon?

A

Visual conscious perception

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What proportion of the optic nerve fibres crossover in the optic chiasm in horses, dogs and cats?

A

Horse - 85%
Dog - 75%
Cat - 66%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the significance of the proportion of optic nerve fibres that crossover in the optic chiasm in different species?

A

An animal with fewer fibres crossing over e.g. human will show a much less prominent indirect PLR. This should be taken into account as a reduced PLR cannot always be assumed to be a lesion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Outline the neural pathway of vision…

A

Retina –> optic nerve –> optic chiasm –> optic tract –> lateral geniculate nucleus –> optic radiation –> occipital lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does the optic nerve differ from the other CN?

A

It is an extension of the CNS
Myelinated
Has retinal ganglion cells, glial cells and meninges

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How can an animal’s vision be assessed?

A 
Dim vs bright light
Observing the animal moving in an unfamiliar env
Negotiating an obstacle course
Visual placing
Menace response
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Outline the efferent neural pathway in the menace response…

A

Occipital lobe –> Associated fibres –> Motor cortex –> Projection fibres –> Pontine nucleus –> Transverse fibres of the pons –> Cerebellar cortex –> Efferent cerebellar fibres –> Facial nuclei –> Facial nerve –> Obicularis oculi muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which muscle is responsible for closing the eyelid?

A

Obicularis oculi muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When can the menace response be absent without any pathology?

A

<10-12w old SA (haven’t learned it yet)
Stressed patients
Lethargic patients
Disorientated patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What effects can forebrain dysfunction have on mental status?

A

Altered –> depression, delirium, confusion, stupor, coma
Behavioural changes e.g. hemi-neglect syndrome
Seizures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is hemi-neglect syndrome?

A

One hemisphere of the brain is damaged which causes a deficit in attention to and awareness of one side of space e.g. only eating from one half of a food bowl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How can gait be affected by forebrain dysfunction?

A

No change
Head pressing, pacing, circling
Proprioceptive ataxia and tetraparesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How can posture be affected by forebrain dysfunction?

A

Head turn (+body turn, circling) towards side of lesion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Are postural reaction deficits lateral or contralateral?

A

Contralateral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the 3 branches of the trigeminal nerve?

A

Ophthalmic
Maxillary
Mandibular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which branch of the trigeminal nerve has motor components?

A

Mandibular

28
Q

In forebrain dysfunction, would decreased facial sensation be ipsilateral or contralateral to the side of the lesion?

A

Contralateral

29
Q

How are spinal reflexes affected by forebrain dysfunction?

A

Unaffected unless multifocal

30
Q

Where is the neurological lesion in a dog with these clinical signs?
Depressed
Decreased facial sensation on the left
Right sided head turn
Decreased menace response and vision on left
Decreased postural reactions on left

A

Right forebrain

31
Q 
Where is the neurological lesion in a cat with these clinical signs? 
Depressed, v lethargic
Decreased facial sensation on right
Absent menace response bilaterally
Left sided head turn
Decreased postural reactions on right
A

Left forebrain

32
Q

What are the parts that make up the brainstem?

A

Midbrain - mesencephalon
Pons - metencephalon
Medulla oblongata - myelencephalon

33
Q

What are the cranial nerves?

A 
I. Olfactory
II. Optic
III. Oculomotor
IV. Trochlear
V. Trigeminal
VI. Abducens
VII. Facial
VIII. Vestibulocochlear
IX. Glossopharyngeal
X. Vagus
XI. Accessory
XII. Hypoglossal
34
Q

Are the autonomic fibres of the CN symp, parasymp or a mixture?

A

Parasympathetic only

35
Q

Outline the mnemonic for CN functions…

A

Some say marry money but my brother says big brains matter more

36
Q

Where in the brainstem do the CN come from?

A

I, II - forebrain
III, IV - midbrain
V - pons
VI-XII - medulla oblongata

37
Q

What is the ARAS? What is its function?

A

Ascending reticulation activating system

Activates the cerebral cortex –> awake state, level of consciousness

38
Q

What happens when the ascending reticulation activating system is depressed?

A

Sleep

39
Q

What is the reticular formation? What functions is the reticular formation involved in?

A 
A meshwork of neuronal cell bodies:
resp
CV
voluntary excretion
swallowing
vomiting
muscle tone
voluntary movement
40
Q

What is the function of the red nucleus and where is it found?

A

Gait generation.

Midbrain - contralateral

41
Q

Where does a dysfunction occur that results in decerebrate/decerebellate rigidity?

A

Decerebrate - midbrain

Decerebellate - cerebellum

42
Q

What are the roles of the oculomotor n?

A

Motor and parasymp to extraocular m
Sphincter pupillary muscle contraction
Levator palpebrae superioris m

43
Q

Outline the innervation of the extraocular m…

A

Oculomotor - superior rectus, inferior rectus, medial rectus, inferior oblique
Trochlear - superior oblique
Abducens - lateral rectus, retractor bulbi

44
Q

Where are parasymp nerve cell bodies found?

A

Near to the efferent muscle

45
Q

What kind of innervation causes the PLR?

A

Parasympathetic

46
Q

Outline the neural pathway of the PLR…

A

Retina –> optic nerve –> optic chiasm –> pretectal nucleus –> oculomotor nucleus –> oculomotor n –> ciliary ganglion –> short ciliary nerve –> iridal sphincter muscle

47
Q

Define dyscoria. How does this appear in cats? What is it assoc with in cats?

A

Abnormal pupil shape.
Cats - D-shaped pupil
FeLV-assoc lymphosarcoma infiltration.

48
Q 
Where is the lesion in a dog with the following clinical signs?
Absent menace response OU
Fixed dilated pupils OU
Normal fundus
Depressed
A

Bilateral optic nerves, optic chiasm

49
Q

Where is the lesion in a dog with the following clinical signs?
Right dilated pupil
Absent direct PLR
Ventrolateral strabismus

A

Oculomotor nevre

50
Q

Which m does the trochlear nerve innervate?

A

Dorsal oblique extraocular muscle

51
Q

How does a dysfunctional trochlear nerve appear in cats and dogs?

A

Cats - tilted pupil

Dogs - cannot tell due to round pupil

52
Q

What is the role of the tectotegmentalspinal tract? Where does it originate?

A

Sympathetic innervation to eye which regulates pupil response to emotional factors arising from the midbrain

53
Q

Which muscles does the mandibular branch of V provide motor and sensory innervation to?

A

Temporalis
Masseter
Pterygoid (lateral and medial)
Digastricus rostral

54
Q

What causes dropped jaw? What are the clinical signs?

A

Dysfunction of the motor component of the trigeminal nerve (mandibular branch) –> inability to close the mouth

Hypersalivation
Difficulty drinking and eating
Abnormal facial sensation
Horner’s (sometimes)

55
Q

What are non-neuro DDx for dropped jaw?

A

Bilateral luxation of the temporomandibular joint
Mandibular fracture
Oral FB –> can’t close mouth

56
Q

What diagnostic tests can be used to find the cause of dropped jaw?

A 
Haem and biochem
Radiographs of thorax
Abdom US
MRI of brain
CSF
57
Q

How is dropped jaw treated?

A

Elastic band/strap around muzzle when eating/drinking

58
Q

What muscle does the abducens n supply motor innervation to?

A

Retractor bulbi extraocular muscle

59
Q

What is a clin sign of abducens n dysfunction?

A

Pupil of eye pointing medially

60
Q

What can cause facial neuropathy?

A 
Infection of middle/inner ear
Trauma
Neoplasia
Polyneuropathy
Idiopathic
61
Q

What is the most common cause of facial neuropathy in dogs?

A

Idiopathic

62
Q

What is a clinical sign of vestibulocochlear dysfunction?

A

Hearing loss

63
Q

What structures does the glossopharyngeal nerve provide motor, sensory and parasymp innervation to?

A

M - pharynx, palatine structures
S - caudal 1/3 tongue and pharyngeal mucosa
P - parotid and zygomatic glands

64
Q

What structures does the vagus nerve provide motor, sensory and parasymp innervation to?

A

M - larynx, pharynx, oesophagus
S - larynx, pharynx, thoracic and abdom viscera
P - thoracic and abdom viscera

65
Q

What innervation does the hypoglossal nerve supply?

A

Motor to the muscle of the tongue

66
Q

Why does a lesion to the brainstem result in a stuporous or comatose mental state?

A

Loss of activation of the ascending reticulation activating system - - > loss of consciousness

Neurology (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions