Audiology Exam 2 (Midterm)

why is otoscopy used

detect collapsing canals, examining pinna for malformations, ensuring that canals are not occluded with cerumen

what is seen with otoscopy

tympanic membrane structures

A

manubrium of malleus

D

umbo of malleus

C

incus

B

cone of light

what questions should you ask adults in a case history

open ended questions

types of testing for children

visual reinforcement audiometry & conditioned play audiometry

visual reinforcement audiometry

6 months- 2 years, use warble narrow band noise​, use lights/toys/videos​, placed at 45-90 degrees from the child's forward facing position

conditioned play audiometry

2 – 4 years​, use different toys and stimuli​, positive reinforcement and enthusiasm​

purpose of audiometry

to find the hearing threshold

threshold

the lowest sound a person can reliably respond to 50% of the time

testing- pure tone AC

250-8000 Hz

testing- pure tone BC

250-4000 Hz

when do you test interoctaves

gap of 20 dB or more

testing- frequency presentation

1000 - 2000 - 4000 - 8000 - 1000 (retest) - 500 - 250​

tuning fork types

weber & rinne

weber tuning fork

determines if affected ear has conductive or sensorineural hearing loss, stem placed on forehead

rinne tuning fork

tests air conduction vs bone conduction, stem placed on mastoid bone

3 parts of audiogram interpretation

degree, type, configuration

conductive hearing loss

BC normal, AC abnormal, gap between AC & BC > 10 dB

sensorineural hearing loss

BC abnormal, AC abnormal, gap between AC & BC ≤ 10 dB

mixed hearing loss

BC abnormal, AC abnormal, gap between AC & BC > 10 dB

headphones IA

40 dB

inserts IA

55 dB

what are inserts best used for

collapsing canals

IA bone conduction

0 dB

air conduction equation

TE AC-NTE BC=  >  IA

bone conduction equation

TE AC-TE BC= > 10

speech reception threshold

threshold test: lowest level a patient can accurately respond to stimulus, tested with spondee words (two syllable words with equal stress), 2/4 words or 50% of the time

pure tone average

average of thresholds of each ear individually (500, 1k, & 2k Hz)

word recognition score

supra threshold test, 40 dB SL to the SRT

stria vascularis

system of cells that maintains the positive charge of the endolymph

fundamental frequency

lowest frequency of a complex waveform

unit of measure is used to define intensity on the audiogram (hearing evaluation form used by audiologists)

dB HL

total effect of the middle ear allows for ___ dB of increased gain from the tympanic membrane to the oval window

33

acoustic reflex

bilateral response to loud stimuli and occurs above 80 dB SPL

phase locking

a theory which refers to which type of neural coding in the cochlea frequency coding

which part of the ear serves the function of transducing mechanical vibration into hydromechanical energy?

stapes

A

reissner’s membrane

B

stria vascularis

C

spiral ligament

D

organ of corti

E

scala tympani

F

spiral ganglion

G

scala media

H

scala vestibuli

5 divisions of auditory system

outer, middle, inner, auditory nerve, central auditory nervous system

outer ear functions

funnels sound, protects ear, transfer function (15-20 dB), acoustic vibration 

functions of middle ear

acoustic vibrations turn into mechanical vibrations, impedance matching (33 dB increase), acoustic reflex

eustachian tube normal state

closed

eustachian tube function

equalize pressure

inner ear functions

shearing of hair cells, depolarization, mechanical vibrations to hydromechanical, movement of basilar membrane (tonotopic organization)

D

outer hair cell

A

tectorial membrane

C

auditory nerve fibers

B

inner hair cell

inner hair cells

passive process of cochlea, 1 row, 3500 in single row

outer hair cells

active process of cochlea, 3 rows, w shaped, embedded in tectorial membrane

where is the cochlea houses

petrous portion of temporal bone

T or F- a lower frequency has a longer wavelength

true

frequency theory

pattern of discharge codes for frequency

place theory

frequency info coded where peak of traveling wave occurs

frequency coding

theories to describe how frequency is encoded within the cochlea