Lecture 7

Question 1

When to use a hearing aid

Answer 1

The more loss, the greater benefit from a hearing aid
Greater degree of loss reduced benefit
Most often used for sensorineural
Motivation
Lifestyle

Question 2

Bilateral hearing aids

Answer 2

Better speech recognition in noise
Better localization ability
Less power required from each hearing aid
Almost always better, but obviously more expensive

Question 3

Hearing aids can

Answer 3

Speech understanding in quiet
Speech understanding in noise
Loud sounds tolerable
Comfortable fit

Question 4

Hearing aids can’t

Answer 4

Give perfect hearing
Bionic hearing
Get rid of annoying sounds
Cure hearing loss
Work instantly

Question 5

How a hearing aid works

Answer 5

Microphone changes sound to electricity
Amplifier boosts electrical signal
Receiver changes electricity back to sound
Battery for power
Controls to adjust hearing aid response

Question 6

Behind the ear (BTE)

Answer 6

Most powerful, durable (don’t have to clean as often), lowest repair rate, easiest to operate, largest controls but may be difficult to position behind the ear

Question 7

In the ear (ITE)

Answer 7

Custom made
Easiest to insert for wearers with dexterity problems
Suitable for all BUT severe hearing loss
Limited by power

Question 8

In the canal (ITC)

Answer 8

Smaller batteries and volume wheel, may be difficult for wearers with dexterity or vision problems
Suitable for mild to moderate hearing loss

Question 9

Completely in the canal (CIC)

Answer 9

Smallest aid
Highest repair rate
Not suitable for: dexterity/vision problems, usually shaped or small ear canals, severe loss

Question 10

Open fit

Answer 10

Has BTE processor, thin tube, and open mold
Can be fit same day in office
May be prone to feedback
Not suitable for greater than moderate hearing loss

Question 11

Bone anchored hearing system (BAHS)

Answer 11

Transmits sound the same way as the bone conduction vibrator used for audiometry
Surgically implanted
Main uses: for permanent conductive loss, atresia, profound unilateral loss

Question 12

Goal when fitting hearing aids

Answer 12

Make soft sounds audible
Make average speech maximally audible
Make sure loud sounds are comfortable

Question 13

Gain

Answer 13

How much the hearing aid has increased the sound level

Question 14

Frequency response

Answer 14

Amount of gain as a function of frequency, for example most hearing losses are worse at high frequencies and require a hearing aid with more gain in the high frequencies

Question 15

Linear hearing aids

Answer 15

Provide same gain for every input level until they reach maximum limit

Question 16

Compression hearing aids

Answer 16

Automatically adjust volume, more gain for soft input, less gain for loud input
Can be adaptive
Detectors in the hearing aid monitor the sound level
Different amounts of compression at different frequencies

Question 17

Directional microphone

Answer 17

2 microphones, one forward and one backward facing
- in directional mode, amplifies sound from the front, reduces sound from the rear
Improve speech understanding in noise by 30%

Question 18

Feedback management

Answer 18

Get ears cleaned out
Make sure earmold fits tightly in the ear
Reduce high frequency gain
Turn the volume down
Feedback cancellation

Question 19

Feedback cancellation

Answer 19

Hearing aid feature that can detect feedback and then produce a signal that is opposite in amplitude and phase and in doing, eliminate the signal

Question 20

Hearing aid trouble shooting

Answer 20

Clean?
Broken?
Battery?
Sound?

Question 21

Cochlear implant

Answer 21

Assistive technology for people with severe to profound hearing loss who do not benefit from conventional amplification
External: speech processor and transmitter coil
Internal: receiver-stimulator, electrode array

Question 22

CI candidacy adults

Answer 22

Moderate to severe/profound hearing loss
Limited benefit from amplification
No medical contraindications
Realistic expectations

Question 23

CI candidacy children

Answer 23

Bilateral severe to profound
Limited benefit from hearing aids for 3-6 mos
At least 12 months old
Inner ear can accommodate the implant
No medical contraindications
Family with good motivation and realistic expectations
Enrolment in appropriate education program