Auditory and Visual System

Question 1

One more time: what forms the brain stem? (Top to bottom)

Answer 1

midbrain, pons, medulla oblongata

Question 2

The midbrain is made of four masses: the …

Answer 2

inferior and superior colliculi.

Question 3

The midbrain is important for reflexes of the ___________.

Answer 3

Eyes and ears.

Question 4

Which part of the midbrain is involved in that cool turning reflex you tell people about?

Answer 4

INFERIOR colliculi

Question 5

Which part of the midbrain is used for conjugate eye movements during environmental surveying?

Answer 5

SUPERIOR colliculi.

Question 6

What is CN III?

Answer 6

Oculomotor

Question 7

Which is CN IV?

Answer 7

Trochlear

Question 8

What number CN is the oculomotor?

Answer 8

Oculomotor: CN III

Question 9

What number CN is the trochlear?

Answer 9

Trochlear: CN IV

Question 10

In damage to CN__, the contralateral eye can’t accompany the other eye downward

Answer 10

CN IV

Question 11

In damage to CN__, there is [pretty much total] palsy of the opposite eye?

Answer 11

CN III

Question 12

Which CNs exit the midbrain?

Answer 12

III and IV

Question 13

Which CNs exit the pons?

Answer 13

VI

Question 14

Which is the abducens nerve?

Answer 14

CNVI

Question 15

Which nerve is CN VI?

Answer 15

Abducens

Question 16

Damage to CN VI means the affected eye can’t look _______

Answer 16

outward (MEDIALLY).

Question 17

Which nerve is the major face signalling one and also chewing and swallowing?

Answer 17

Trigeminal nerve (CN V)

Question 18

Which CN is the trigeminal nerve?

Answer 18

CN V

Question 19

Which one is CN V?

Answer 19

The trigeminal nerve.

Question 20

I thaid thomething muthst have happened to my ________ nerve (VII)

Answer 20

hypoglossal nerve XII

Question 21

Which nerve covers facial expression and so many fluids north of your neck?

Answer 21

Facial nerve VII

Question 22

Which are the only three nerves that show up in a newborn’s AEP (in order)?

Answer 22

1, 3, 5

Question 23

Newborn ERP in order:

Answer 23

1,3,5

VIII, pons, inferior colliculi (midbrain)

Question 24

Where is CN V activity coming from in the AEP?

Answer 24

midbrain, near the inferior colliculi.

Question 25

Why am I hearing about baby EAPs?

Answer 25

Because latencies in the EAPs are a diagnostic tool for baby hearing - and are a useful test when babies are born underweight or axphyxiated.
Hearing = proper speech development

Question 26

One more time: ERPs can be in response to actual or ________ stimuli.

Answer 26

anticipated.

Question 27

In an AEP:
N1 @
P1 @
Seen in the ___________.

Answer 27

N1: 80-90ms
P1: 170ms

Auditory cortex of the temporal lobe.

Question 28

What’s one thing we’ve learnt from AEP latencies in newborns?

Answer 28

The newborn auditory system can distinguish different speech sounds.

Question 29

What’s an oddball sign of trouble in infants?

Answer 29

ta ta ta ta da ta ta

oddball da won’t show latency in at-risk infants.

Question 30

What’s the ERP sign for hemianopia?

Answer 30

Depressed P1 aimplitude at 50-60ms

Question 31

Which colour blindness confuses green and red?

Answer 31

deuteranopes

Question 32

Which colour blindness is a deep-red insensitivity?

Answer 32

protanopia

Question 33

Which colour blindness is a confusion of red, blue and green?

Answer 33

tritanopia

Question 34

deuteranopia
protanopia
tritanopia

Answer 34

red/green
deep-red insensitivity
red/blue/green

Question 35

You’ve got that colour blindness if your ERPs are…

Answer 35

ABSENT

Question 36

What can ERPs tell us about coma?

Answer 36

If ERPs are normal, the coma’s not the brain’s fault. It’s toxic or metabolic (e.g. overdose or uremia)

Question 37

A tumor in the midbrain will look like this:

Answer 37

Absence of ERP following wave III.

Question 38

Damage to the cochlear nucleus will flatten all ERPs after…

Answer 38

following wave I.

Question 39

All waves after wave I are absent in an AEP. Where’s the damage?

Answer 39

Cochlear nucleus.

Question 40

All waves after wave III are absent in an AEP. Where’s the tumour?

Answer 40

Midbrain.

Question 41

Reduced amplitudes in N100 and N200, plus latencies of N200 and P300 look like…

Answer 41

closed head injury causing auditory problems.

Question 42

Closed head injury causing auditory pathway problems. What’s that look like?

Answer 42

Low amplitude of N100 and N200 + delayed latency of N200 and P300.

Question 43

Reduced N200 amplitude: bad news…

Answer 43

… there’s visual processing damage from your closed head injury.

Question 44

Is ERP useful to indicate brain death?

Does it tell us much more than a flatline EEG?

Answer 44

YES.
In a study of 50 people, 19 showed ERPs.
3 came back.

Question 45

Multiple sclerosis can be detected with 90% accuracy using ERPs compared to 70% accuracy with MRIs. What stimuli do we use and what do we see?

Answer 45

Patter-evoked potentials,
VISUAL P100 is greatly delayed
BRAINSTEM delayed central transmission (latency difference between I and V)

Question 46

What’s Alzheimer’s look like? It’s only part of what closed head injury looks like.

Answer 46

P300 attenuated and oddly distributed across the cerebrum.

To AEPs, P300 had prolonged latency and N400 was incompatible with the stimuli.

Question 47

P300 attenuated and oddly distributed across the cerebrum.
To AEPs, P300 had prolonged latency and N400 was incompatible with the stimuli.
Looks like…

Answer 47

Alzheimer’s.