Hearing Aids Flashcards
Goals of amplification
Increase strength of auditory signal to make audible
Provide clean, clear signal
Shape signal in order to meet individuals needs
Protect ear from uncomfortable loudness
Meet expectations of the wearer
Rationale for use of amplification
Hearing lose = issue of reduced auditory information
- restore depleted auditory info
- amplify sounds that enables person to use remaining hearing
People with SNHL have problems tolerating…
Loud sounds
Hearing loss varies as a function of
Frequency
Two people with same audiogram may have different needs because…
Due to different types of cochlea dysfunction
Due to different central system capabilities
Role of audiologist with hearing aids
Appropriate amplification
Evaluation of function
Monitor technical performance
Counseling
Basic parts of a hearing aid
Power supply
Microphone
Amplifiers
Receivers
Microphone
Converts acoustic signal to electrical signal
Amplifiers
Increases the amplitude of weak voltages
Receiver
Converts amplified signal back into acoustical energy
5 types of hearing aids
Body worn and eyeglass hearing aids Behind the ear (post auricular) In the ear (custom fit) Canal hearing aids Completely in canal hearing aids
Body worn/eyeglass hearing aids
Not seen often anymore
Can sometimes be used w infants
Very powerful
Behind the ear
(Post auricular)
Style worn most frequently by children
Adults only choose this 1/3 of the time
Significant amount of amplification for people with severe to profound loss
In the ear custom fit
Custom shell made from ear impression
Choice of 75% adults
School aged children w mild/moderate loss
Can make use of piña enhancements
Canal hearing aids/completely in canal hearing aids
Very small!
Worn by older adults and teens with mild to moderate loss
Uses natural enhancements of piña and canal
Two types of hearing aids
Analog and digital
Digital signal processing allows for..
Greater flexibility
More control and precision over frequency response
Multiple memory capability
Noise cancellation and directional microphones
Binaural hearing aids help with…
Elimination of head shadow Loudness summation Localization Improved SNR Improved speech perception
How to trouble shoot hearing aids
Visual check
Battery check
Listening check
Fit check
Analog vs Digital
Analog: continuously changing signal by electrical current
Digital: sound wave changed into bits, manipulated, and changed back into analog signal
