Quesmed Eyes and Ear

Question 1

Weber’s Test lateralises to the right

Answer 1

Conductive hearing loss in right ear
OR
Sensineural loss in the left ear

Question 2

What does Weber’s test appear louder in?

Answer 2

Ear with no sensineural hearing loss such as:
conductive hearing loss or normal hearing

Question 3

Rinne’s test- positive

Answer 3

Normal ear where air conduction is better than bone

Question 4

Rinne’s test- positive

Answer 4

Abnormality where bone conduction is better than air

Question 5

Weber’s lateralises to the left ear but Rinne’s test is positive for both?

Answer 5

Right sensineural hearing loss

Rinne’s tests for CONDUCTIVE hearing loss

Question 6

Which hearing test is more sensitive?

Answer 6

Weber test

Question 7

How does high frequency sound affect the ear?

Answer 7

Base of the cochlea where membrane has high stiffness and low mass

Question 8

How does gentamicin toxicity manifest?

Answer 8

Vertigo
Loss of balance
Ataxia

Question 9

Where does sound travel after the oval window?

Answer 9

Through perilymph in the cochlea.

Question 10

What is the perilymph?

Answer 10

Located in the scala vestibular and scala tympani. It is rich in sodium and low in potassium.

Question 11

Which structure is responsible for tonotopy?

Answer 11

Basilar’s membrane, located between scala tympani and scala media.

Vibration of the Basilar membrane causes movement of stereocilia and opening of mechanically-gated ion channels to generate action potentials down the vestibulocochlear. Nerve

Question 12

Which sound goes to the base of the Basilar membrane?

Answer 12

High frequency

Question 13

Which sound goes to the apex of the Basilar membrane?

Answer 13

Low frequency

Question 14

What is the role of Reisnner’s membrane?

Answer 14

Diffusion barrier for nutrients from perilymph.

Question 15

What is the function of the middle ear muscles?

Answer 15

Primary function is to increase frequency of air kinetic energy to the level of the cochlear fluid.

Question 16

What is characteristic frequency?

Answer 16

The characteristic frequency is the frequency at which the threshold for generating a nerve impulse is reached

Question 17

Where do the auditory nerve fibres terminate?

Answer 17

Auditory nerve fibres terminate at the cochlear nucleus of the brainstem, between pons and medulla.

Question 18

What is the role of inner hair cells of the ear?

Answer 18

Signal transduction.

Question 19

What is the role of outer hair cells of the ear?

Answer 19

Non-linear amplification of sound

Question 20

Anterior semicircular canal

Answer 20

Up and down movement, involved in protective reflex

Question 21

Lateral semicircular canal

Answer 21

Tilting head side to side

Question 22

Posterior semicircular canal

Answer 22

Left and right movement

Question 23

Saccule

Answer 23

Vertical movement up and down

Question 24

Utricle

Answer 24

Horizontal movement forwards and backwards

Question 25

Low frequency sound travels here?

Answer 25

Helicotrema, between scala vestibula and scala tympani filled with perilymph rich in Na+

Question 26

Where does decassation occur in auditory cortex?

Answer 26

Superior olivary nucleus, located in the pons

Medial geniculate nucleus of thalamus

Question 27

What is the role of inferior olivary nucleus?

Answer 27

Located in medulla for visual information.