Neuroanatomy/exam and localisation Flashcards
(110 cards)
1
Q
describe the innervation of the bladder
A
ANS
symp and somatic = relax detrusor and inc sphincter tone
fills and impulse to pons - says its full
parasymp - contracts detrusor
somatic inhibit = ext sphincter relax and symp are inhibited so int sphincter relaxes
2
Q
UMN lesion to nerves supplying the bladder = ?
A
can’t express itself
3
Q
LMN to bladder = ?
A
dribbles
4
Q
desc the anatomy of the innervation to the eye
A
1st n stem –> t1-3
2nd n t1-3 –> cr cervical ganglion
2rd from here to eye
5
Q
what does this ANS supply to the eye achieve
A
- dilate pupil
- orbitalis m (periorbita, eyelids, 3rd eyelid)
- ciliaris m
- sm m in b vessels and sweat glands
6
Q
what is horners syndrome
A
- miosis
- upper lid ptosis
- 3rd eyelid protruding
- enopthalmos
7
Q
what is the bbb
A
tightly joined endothelial cells alongside the foot-processes of astrocytes
8
Q
what % of drugs get past the BBB
A
5%
9
Q
how does the chemical trigger one work then
A
its not past the BBB
10
Q
name the 3 layers of the meninges
A
dura mater
arachnoid
pia
11
Q
desc the flow of CSF
A
lat ventricles –> inter ventricular forament
- -> 3rd v
- -> mesencephalic aqueduct
- -> 4th v
- -> lateral apertures
- -> subarachnoid space
12
Q
which domestic spp has a surprisingly large vol of CSF
A
horse
13
Q
what is the fact of olfactory, where is the cell body
A
smell - perception
cell bodies in olfactory epithelium (cribriform plate -ish ) not ganglion
synapse of olfactory bulb –> prirform lobe
14
Q
why is the optic nerve not a true nerve
A
surrounded by oligodendrocytes and meninges
15
Q
what m does the oculomotor control
A
D, V, M rectus
V oblique
and elevator palp superioris
16
Q
oculomotor also has a parasymp fat what is it
A
pupillary constriction
17
Q
what n controls the D oblique
A
trochlea - OF THE CONTRALATERAL SIDE
18
Q
what about the L rectus - what controls that
A
abducens
19
Q
what is the fact of the trigeminal
A
facial sensation
motor MM
20
Q
out of the three trigeminal branches - which is the only one with the motor function for the MM
A
mandibular
21
Q
what is the fact of the VII
A
motor to facial expression
sensory to R 2/3 tongue an palate - inc taste
PS to lacrimal, mandible and s-l glands
22
Q
where does the facial nerve run on its way out of the brain
A
thru acoustic meatus –> stylomastoid foramen and middle ear ( at this point the PS fibres separate)
23
Q
what is the relevance of the chords tympani
A
carries facial fibres from the middle eat to serve tongue in taste and sensation
24
Q
what does the vestibulocochlea do
A
hearing and balance using R in inner ear –> medullar
25
GP nerves =
motor to pharynx and palate
sensory to cd 1/3 tongue and pharynx
PS to parotid and zygomatic glands
nuclei is with X in medulla
26
what is the role of the X
m- larynx, pharynx (with GP) and oesophagus
s - larynx, pharynx (with GP) and thoracic/abdo viscera
PA - ALL cr thoracic and abode viscera
27
what is the role of XI, why is it a CN
trapezius, sternocephalicus and brachiocephalicus
28
what does XII do
m - tongue
29
what are the fct LMN
efferent (m) neurones connecting CNS to muscle that needs innervating
30
describe the process of AP prop at NMJ
```
Ca++ channels open
ACh released --> bind to post-syn R
Na open
depol
contract
```
31
desc the 'reflex' arc basic
dendritic stim
sensory periph nerve --> D root and synapses in d column
direct reflex (patella) or interneurone (withdrawal)
then exit via V root to motor periph nerve
syn in muscle
32
why are reflexes useful to vets
localise the lesion
FL= C6-T2
HL = L3-S3
33
can you feel pain without reflex and have a reflex without pain>
yes. a reflex can localise lesions, but doesn't affect prognosis if missing
perception of pain w/wo reflex is a negative prognostic factor! pain fibres shouldn't be damage (v deep)
34
what is the UMN system and its fct
in the CNS, synapse with LMN in GM of SC.
initiate vol movement, maintain muscle tone and control activity
2 tracts - extra + pyramidal
35
what are the extra and pyramidal tracts
```
pyramidal = skills, c. cortex
extrapyramidal = bstem. tonic mech for posture, spinal reflexes.
```
36
what is the diff bw unconscious and conscious proprioception? what tracts do nerves travel in?
- unconsc = segmental reflex, info --> cerebellum. spinocebellar DL tract - ipsilateral
- conscious = info --> cerebral cortex. fascicles gracilis and cuneatus - contralateral at medullar
37
what is the purpose of the endolymph and how is balanace identified
to move relative to perilymph (any labyrinth) with head movement. this connects to utriculus --> saccule and cochlear
38
what is the crust ampullaris?
end of semicircular canal (ampulla) is neuroepithelial hairs in gelatinous cupola.
39
what is the macula
uticulus and saccule there are oval plaques with neuroepithelium covered in gelatinous membrane with otoliths
40
where are the nuclei locations for the vestibular nuclei?
4 x by pons and medulla which go out to:
- SC
- bstem
- cerebellum
41
what is the medial longitudinal fsciculus (MLF)
where axons of vestibular nerves meet nuclei of CNIII, IV and VI (coord eyes)
42
other than the MLF, where else do nerves from the vestibular nuclei go
SC - to + extensor m, inhibit flexors and inhibit contralateral extensor
RF - for motion sickness
thalamus - to perceive balance
cerebellum - inhib
43
what layer of the cerebellum continues to divide after birth
germinal layer
44
what is the fct of the cerebellum
reg motor activity
coordinate and refine movement
maintain equilibrium
regulate tone to maintain posture
45
what afferent (s) nerves synapse in the cerebellum
```
proprioceptive n - spinocerebellar tract
vestib
visual
auditory
UMN - allows reg of motor fct
```
46
desc the position of the optic disc
V-L
47
what are the % of axons that cross to controlat side at the optic chiasm
```
birds/fish = all
H/R = 90%
D = 75
C = 65
Us = 50
```
48
what part of the brain result in perception of sight
occipital cortex
49
what is the PLR and the motor response
PLR - most are contralateral PS oculomotor nerve
motor - R colliculus --> CN III, IV, VI and cervical SN --> move towards visual stim
50
how can you assess conscious perception of sight?
menace
51
how you can you asses s the PLR
shine a light
52
how is sound transmitted into nerve impulse
ossicles vibrate --> move perilymph, basilar membr moves and detected by hair cells which bend sterocilia = impulse
53
where is hearing consciously and reflexly detected
```
consciously = temporal bilaterally
reflex= Cd colliculus
```
54
what causes noise induced deafness
XS noise exposure kills hair cells
55
where is the limbic system mainly and where does it mainly project to
based - c.cortex and diencephalon (thal and hypothal)
| project - hypothal
56
where do UMN synapse for parasymp and symp NS
```
rostral = para
cd = symp
```
57
what is hypocretin and where is it synthesised
regulates sleep
| hypothalm
58
what inv has the hypothalm got with the adenohypophysis
regulates by secreting neuro-endocrine hormones
59
what is the point of the thalamus
conscious perception of all sensory paths
m n relay
projects diffusely with into from ARAS and cerebral cortex/thalamus
60
what is the ARAS
asc reticular activating system
61
what are the fct of the ARAS
arouse
conscious awake
prepare brain for info
62
where does the ARAS receive info from
everywhere
63
why does the ARAS have a role in how bored you get or how easily you learn>
should stimulate your brain to want to learn, be awake etc - so if not = easy bored etc
64
what parts of the brain control mentation.
forebrain and bstem
65
what are the levels of mentation
1. alert
2. disoreintated
3. depressed
4. stuporous
5. comatose
66
what area controls behaviours
f-brain
67
what is hemineglect syndrome
when a structural lesion to fbrain, the animal ignores half the world
68
a lesion where could cause a head tilt
vestibular dz (either central or peripheral)
69
a lesion where could cause a body turn
fbrain.
| called aversion syndrome
70
what is opisthotonus
bwds arching of head, neck and spine from muscle spazm, seen in tetanus etc
71
what are the differences bw:
- de-cerebrate rigidity
and
- de-cerebellate rigidity
de-cerebrate rigidity
- ALL limbs extended
- due to inhib UMN
- lesion = R bstem
- stuporous/comatose
de-cerebellate rigidity
- hyper-extension - FL only
- loss of the inhib of stretch and antigrav mechanism
- lesion = R cerebellum
- normal mentation
72
what is Schiff-sherrington?
hyper-extension of FL and paralysis of HL
| lesion = T/L spine
73
where are the 3 places a lesion could be which would result in ataxia
spinal (subtle - reduced info from CNS)
vestibular (off balance)
cerebellar (drunken - rate, F and range differ)
74
what is the diff bw paralysis and paraplegia
loss of voluntary movement
| also have mono, para, hemi, tetraparesis
75
what is non-ambulatory paresis
when with support, movement it seen - different from paralysis
76
what are the grades for spinal lesions
1-5
| 1 = no deficit, just pain; 3 = paresis, non-ambulatory; 5 = no pain sensation
77
name some postural tests
```
paw postition (upside down)
hopping (lift 1 or 3 limbs)
hip sway
whelbarow
extensor postural thrusts
placing responses (at table, good for cat)
```
78
name some spinal reflexes
- withdrawals, myotactic FL & HL & panniculus
79
why are spinal reflexes useful
to ID whether UMN or LMN
80
desc the myotactic tests in the FL
ext carpi radialis - strike the m at belly --> ext carpus
biceps - strike over digital end of b.brachii and brachialis --> flex elbow and contract muscle
triceps - strike at insertion on olecranon --> ext of elbow and carpus
81
desc the myotactic in HL
patella - strike patella tendon --> ext limb
cr tibial - strike PX --> hock ext
gastrocnemius - strike --> hock ext
perineal - stim perineum with thermometer --> contracts
82
desc withdrawal
pinch digit --> reflex contraction of flex = withdraw limb. hppens wo need for pain sensitisation!
83
desc the panniculus response
pinch skin --> moves 2 x vertebral spaces cr'ally to synapse with lateral thoracic nerve for both L+R --> then synapse with brachial plexus --> bilat twitch
84
why is the panniculus reflex useful
can ID whether T3-L3 lesions or brachial plexus lesions (C6-T2) depending on when the reflex stops
85
what does the palpebral reflex test
V (opth or max) + bstem
| --> VII (to blink)
86
what does the corneal reflex test
V (opthal) + bstem
| --> VII (to blink)
87
what is physiological nystagmus controlled by
VIII (vestibulocochlear) + bstem. if lost - commonly inc IOP
| --> III, IV, VI (to move eyeball)
88
what controls the menace reponse (learnt at 10-12wo)
II (optic) + fbrain, cerebellum and bstem
| --> VII (facial - to move eyelids)
89
what is sensory to stim of nasal mucosa
V (opthalm) + fbrain, bstem
90
what controls the PLR
optic + bstem
| --> III (to change pupil size + some parasymp/symp nn)
91
what is tested by the gag reflex
IX (GP) and X (vagus) + bstem
| --> same output
92
name main signs of a forebrain lesion
- disorientation/depression
- contralat blindness (abn menace, normal PLR)
- normal gait
- ipsilat circuling/head turn/pressing
- decr postural responses in contralat limbs
- behavioural changes, hemi-neglect and seizures
93
why is the bstem so critical
```
- ARAS
regulation centre for CV and resp
CN III --> XII
all sensory and motor tracts pass through
vestibular nuclei
```
94
what are the signs of a bstem lesions
- depression, stupour coma
- CN 3-12 deficits
- vestibular signs
- paresis + dec postural resp of ALL/ipsilat limbs
- de-cerebrate rigidity (all limbs)
- R or CV abn
95
what are the signs of cerebellar lesions
- normal mentation
- normal vision + PLR but ipsilateral abn menace
- vestibular signs (controls bstem role)
- ataxia, wide-base stance, hypermetria
- intention tremor
- de-cerebellate rigidity
- delayed but hypermetric postural response
96
if there is a lesion in the vestibular system, there wil be path nystagmus, can you tell which side the lesion is
yes - on the side with the slowest nystagmus phase
97
the vestibular system has elements both in PNS and CNS. how can you tell from the signs where thelesion is
```
PNS = horizontal or rotationary nystagmus
CNS = vertical mainly
```
98
what is a paradoxical head tilt?
one in the opp direction to lesions w signs of cerebellar dz
| lesion is in the flocculonodular lobe or cd. cerebellar peduncle
99
is the lesion is C1-T2 or T3-S3 which limbs are effected?
All limbs
or HL
100
what reflexes test LMN
spinal reflexes
- C6-T2 = FL
- L4-S3 = HL
101
what would a lesion in C1-C5 cause
all or hemi paresis
normal spinal reflexes
norm tone
horners, resp issues, urinary retention
102
a lesion in C6-T2 =
all or hemi /deficits and paresis
reduced: tone, atrophy, spinal reflexes in FL and panniculus
horners, resp issues, urinary retention
103
a lesion in T3-L3
HL paresis and deficits
normal spinal reflexes
reduced panniculus cd to lesion
104
a lesions L4-S3
HL paresis and defects in 1+
| reduced: tone, atrophy, spinal reflexes in HL, anal tone and perineal reflex
105
what are the signs of oa motor neuropathy
flaccid paralysis
reduced tone
atrophy
reduced spinal/CN reflexes
106
what are the signs of a sensory nerve neuropathy
decr sensitisation and self mutiliation increases (para-aesthesia)
reduced spinal/CN reflexes
107
give an examples of a cause of the following:
| pre-syn, post-synaptic and enzymatic junctionopatby
pre - clost botulinum
post - myasthenia gravis
enzymatic - OPs
108
what are the only indication of myopathies
generalised weakness/exercise intol (stiff)
109
what are the 3 main causes of generalised myopathy
congen/inherited
inflam or infectious
metabolic
110
what does a painful myopathy suggest might be the cuase
inflam
space occupying
trauma
