parts on hearing aids - Answers microphone, amplifier, receiver
microphone - Answers Picks up sound, on outside of hearing aid
Every hearing aid has a microphone, some even have 2
Mic in the front is the actual mic and the one in the back is the directional mic
If it does not work, we cannot pick up sound
amplifier - Answers Amplifies the sound in the hearing aid
receiver - Answers Where the sound comes out of the speaker, If it does not work, we cannot produce
sound
Intermodulation - Answers Multiple frequencies causing problems
500 and 300 Hz>-----
> 500, 300, 200, 800, 600, 1000 Hz
Harmonic - Answers Frequency specific
500 Hz>-------
>500, 1000, 1500, 2000 Hz
Impact of each of these types of distortion on speech discrimination - Answers Causes hearing aid to
make unwanted sounds and difficulties with speech discrimination
Body - Answers Used in third world countries, we dont use
BTE - Answers Located behind the ear, has a hook that attaches to the ear mold
Used with ears with medical problems (curved ear canal, microtia, constant drainage, open perforation,
with any fluid coming out, cauliflower ear
Superpower BTE- most powerful
RIC-receiver in canal, all in the ear canal open BTE
Thin tube BTE_ open BTE, not in the ear, little as possible in the canal, less power due to sound escaping
RICS and thin tubes - don't plug you up or make an echo sound, keeps the ear canal as open as possible
, advantages of BTE - Answers Advantages: can be fit to any motivated HI person, has a lot of flexibility
with features, great gain and MPO than smaller aids, Tcoil is stronger, only the ear molds needs to be
replaced over time, DAI if available, suitable for ears with medical problems
disadvantage of BTE - Answers more conspicuous than smaller aids, may fall off during work or
recreation, may seem more difficult to insert, remove, and a just volume control that a smaller hearing
aid
ITE - Answers Completely fill concha and ear canal
advantages of ITE - Answers small and therefore more acceptable, better mic placement that BTE, more
secure fit, easy to insert and remove, and to adjust the volume
disadvantages of ITE - Answers not generally a good option for children, Dont consider for kids until they
are done maturing 10-12 and their ears stop changing and growing
advantages of ITC - Answers small and even less conspicuous and therefore more cosmetically appealing
than ITE, portion of the concha is left free, allowing for natural resonance and diffraction effects, less
difficulty with feedback when using the telephone, compared to ITE's, less wind noise due to more
deeply seated mic
disadvantages of ITC - Answers may not be enough gain and output, tcoil is not available in all ITC's,
smaller battery size, difficulty for some people to manage, size and circuitry (if patients ear is very small
there may not be enough room to place the circuity in an ITC shell), more expensive than ITE
CIC - Answers Completely in the canal, cannot be seen
advantages of CIC - Answers cosmetically appealing, inc output because of deep canal placement,
occlusion effect is dec, easy to insert and remove, reduction in wind noise since mic is in ear canal, dec
feedback
disadvantages of CIC - Answers limited circuits and adjustments available, small battery require good
dexterity, more expensive than ITC, Tcoil may not be available
bone conduction - Answers for patients who have atresia or a lot of ear problems in the outer ear space,
severe microtia, born without ossicles forming, single sided deafness, chlosteotoma, OR with unilateral
HL- no hearing all at all in one ear, BC sound travels to opposite ear's cochlea, end result = binaural
hearing
two types of bone conduction - Answers traditional and implantable
traditional bone conduction - Answers a vibrator is placed behind the ear and over the mastoid rarely
used
implantable - Answers BAHA