CSD 230 Exam 1 Flashcards
Acoustics
Science of sound
Amplitude
Amount of vibration of a mass from the position of rest the farthest point from
the position of rest (up and down on chart)
Condensation
Region of a sound wave characterized by an increased density of molecules
Opposite of rarefaction
Damping
Decrease in the amplitude of a vibrating body over time
Decibel (dB)
Unit of sound intensity level
The logarithm of the pressure of a sound to a reference pressure (usually
0.0002 dynes/cm2)
Frequency
Number of complete cycles (or oscillations) of a vibrating body in a specified unit of time
Hertz (Hz)
Intensity
Magnitude of sound energy per unit area
Similar to volume
Force of a sound wave
Pitch
The psychological perception of frequency
Pure Tone
Single-frequency tonal sound
Aka a sinusoid
Refraction
Region of a sound wave characterized by an area of less dense molecules
Opposite of condensation
Resonance
Natural rate of vibration of a mass
Shatter a glass with a musical tone
Sound
Vibration through a medium (air/liquid)
Primary sections of the ear
outer, middle, inner, retrocochlear
Peripheral
Central
Outer ear
* Middle ear
* Inner ear
* CN (8)
* Cochlear nucleus on the brainstem
- Rest of the brainstem
- Cortex
Hearing Threshold
Softest intensity at which one can hear a sound
Frequency dependent
Pinna effect
loudness and intensity differences for localization
a-
on, in, at
genesis
origin/creation
cephal
head
dys
bad
-pathy
disorder
oto
ear
media
middle
-rreha
drainage
4th week of gestation
Ossicles start to develop
External gill groove starts to form
Start to see vestibular system
38th Day of
Gestation
Differentiation of otic vesicle yields 3 major
subdivisions of the inner ear
* Endolymphatic sac
* Endolymphatic duct
* Utricular and saccular portions of the inner
ear
Fifth to Sixth Week of Gestation
External ear begins to form
* Start to see the EAC
* External ears form from 6 thickenings
* “axon hillocks”
* Nasopharynx develops
* Upper lip develops
* Beginning of the semicircular canals
* 6th week
7th Week of
Gestation
First full turn of the cochlea develops
Vestibular system is fairly developed
* Outer ear is visible
9th week of gestation
2 ¼ turns of the cochlea and semi-circular
canal system are developed.
Ear is more upright and more forward on the
head.
3rd month
Ossicles are formed, but still in fluid
A meatal plug forms at the bottom of the pharyngeal cleft.
The cochlea is adult-like by _____ weeks of gestation, while the middle ear
continues to develop until the end of gestation.
25th
