audiology unit 1

propagation

how sound is transferred through a medium

force

what needs to be applied for a sound to be propagated?

intertia

the opposition of an object from its resting state or its ability to remain in motion once it has started

elasticity

a restoring force, refers to how easily an object moves back to its resting/starting position

reciprocal

inertia and elasticity are ____ characteristics

condensation

areas of increased molecules

rarefaction

areas of decreased molecules

pressure

what is equal to force/area?

waveform

what graph depicts increases and decreases in pressure over time (relationship between displacement and time)

sinusoid

a pure tone is also known as a ___

periodic

describes a sine wave, indicates that the waveform repeats itself at fixed temporal intervals

aperiodic

describes a waveform that does not repeat, has a random temporal pattern (example - noise)

phase

each point along the sine wave is called a ____, it represents what position the object is in its cycle of vibration, can be any value from 0-360

frequency

the number of vibrations the sine wave completes in a second

period

the time it takes to complete one cycle of vibration, or go through a 360 degree cycle

dB and frequency

always use a WHOLE number when writing __*___ and ____*__

wavelength

the distance between successive compressions and rarefactions; distance encompassed by 1 cycle of vibration

1100 ft/sec or 343 m/sec

constants for the speed of sound in air

faster

because sound is proportional to the density of the conducting medium, sound travels **faster or slower** in humid air?

wavelength = speed of sound/frequency

formula for wavelength

20-20,000 Hz

frequency range of human hearing

minimum audible pressure

what does the MAP curve stand for?

MAP curve

the ____ shows us the least amount of pressure needed for the human ear to hear at a given frequency (50% of the time)

compares performance to intensity

P/I function of MAP curve

frontal, sagittal, transverse

3 anatomical orientations

anterior/posterior

directional terms used for coronal (frontal) plane

lateral/medial

directional terms used for the sagittal plane

superior/inferior

directional terms used for the transverse plane

peripheral/central

two major divisions of the auditory system

outer, middle, and inner ear

name the three parts of the peripheral auditory system

brainstem and auditory cortex

two divisions of the central auditory system

pinna (auricle) and external auditory canal

two main structures of the outer ear

protect, amplify sound, localization of sound, channeling sound to more medial structures

function of the outer ear (pinna and external auditory canal)

passively, 2.7-3 kHz

how does the external auditory canal amplify sound? at what frequency?

15-20 dB

how much does the external auditory canal amplify sound at 2700-3000 Hz?

20log(P1/P2)

decibel formula

20 micropascals

what does P2 equal in the dB equation?

complex signals

auditory signals that are comprised of more than one frequency

Fourier

most of what we know about the physical composition of complex signals comes from the work of a French mathematician named ____

prevention, assessment, rehabilitation

purpose of audiology

false (threshold of audibility varies across frequencies)

true or false - the ear is equally sensitive to all frequencies

MAP curve

subjects who were young, healthy, and had no known history of ear disease were given headphones to create the _____

cartilaginous, osseous

the lateral 1/3 of the EAC is ___, and the medial 2/3 is

hospitals, schools, private practices

where can audiologists practice

threshold of audibility

at the ___ the stimulus is strong enought o evoke a sensation of sound or have an effect for the listener

psychometric function

what function was used at each frequency to create the MAP curve?