Hearing Science Final

The amplitude response of a system is also commonly know as the _____ response

Frequency

If a system reproduces all frequencies with equal amplitude, it is said to have a _____ amplitude spectrum

Flat

In a linear system, what happens to the output amplitude when the input amplitude is increased?

A proportional increase in output amplitude is achieved

How does a linear system affect the shape of an input sinusoidal waveform?

The shape of the waveform is unaltered and remains sinusoidal

Amplitude distortion is also called ______ distortion

Nonlinear

What is the term for the distortion where the peaks of a sine wave are "flattened" by a nonlinear system

Peak clipping

If a sine wave enters a nonlinear system, the resulting output contains energy at ______ of the fundamental frequency

Harmonics

What type of distortion occurs when the input signal is a complex waveform rather than a sinusoidal?

Intermodulation distortion

Intermodulation distortion creates two products: harmonics and _______

Combination tones

What are the two subdivisions of combination tones?

Difference tones and summation tones

What effect does shortening the duration of a sine wave have on its amplitude spectrum? (Transient distortion)

Energy is spread to other frequencies, creating a continuous spectrum rather than a line spectrum

What sound is produced if the rise time or fall time of a signal is too short?

A click/pop

What is the name for the visible part of the outer ear?

Pinna

What is the technical name for the opening of the ear canal?

External auditory meatus

What are the two main portions of the ear canal?

The cartilaginous portion and the osseous (bony) portion

What is the primary function of the pinna?

Acts as a funnel to direct sound into the ear canal

How many decibels are typically gained by cupping your hand around your ear?

Around 8 dB

What is the estimated first resonant frequency of the human ear canal?

Around 2800 Hz

The bowl shaped area of the outer ear that enhances sound is called the ______

Concha

Which localization cues are the primary indicators for estimating sound elevation?

Monaural localization cues

What are the two types of binaural localization cues?

Interaural intensity difference (IID) and interaural time difference (ITD)

Approximately how long is the human ear canal?

About 2.5 cm

Name the three bones of the middle ear (ossicles)

Malleus, incus, and stapes (hammer, anvil, and stirrup)

What is the technical term for the eardrum?

Tympanic membrane

What is the tip of the cone shaped tympanic membrane called?

Umbo

Name the two portions of the tympanic membrane defined by their relative tension

Pars tensa and pars flaccida

What is the name of the ring shaped ligament that holds the tympanic membrane in place?

Annulus

The cone of light can be seen at ____ o'clock when examining the left ear

7

The cone of light can be seen at _____ o'clock when examining the right ear

5

Where does the footplate of the stapes sit within the middle ear anatomy?

The oval window

Name the thin bone layer that separates the middle ear from the brain cavity

Tegmen tympani

What structure connects the middle ear space to the nasopharynx?

The Eustachian tube

What are the primary purposes of the Eustachian tube?

To equalize middle ear pressure and to drain accumulated fluid

What is the medical term for a middle ear infection

Otitis media

Name the two muscles located in the middle ear

Tensor tympani and stapedius

Which cranial nerve innervates the stapedius muscle?

Cranial nerve VII (Facial)

Which cranial nerve innervates the tensor tympani muscle?

Cranial nerve V (Trigeminal)

What is the purpose of the middle ear regarding energy conversion?

Acts as a transducer, converting acoustic energy into mechanical energy

The middle ear acts as a _____ matching device

Impedance

What is the area ratio between the tympanic membrane and the stapes footplate?

17:1

Approximately how many decibels of pressure gain does the area ratio of the middle ear provide?

About 25 dB

Name the three mechanisms of the middle ear pressure transformer

Area ratio, ossicular lever, and buckling effect

What is the role of the middle ear muscles when exposed to very loud sounds?

They tense up to prevent damage to hearing

What is the primary sensory organ for hearing in the inner ear?

The cochlea

What are the three types of distortion?

Frequency distortion, transient distortion, and amplitude distortion

Linear systems produce only which type of distortion?

Frequency distortion

What happens to mass reactance and stiffness reactance at an objects resonant frequency?

They cancel out

What is the inverse square law?

Sound intensity is inversely proportional to the square of the distance from the source

Increasing the distance from the sound source by 2 reduces the intensity by ______

1/4

A jet airplane takes 2 hours to travel 1600 miles in a straight line. What is the average velocity of the jet?

800 mph

A grandfather clocks tick once when the pendulum swings from left to right and once again on the swing from right to left. There are two ticks each second. What is the frequency of pendulum motion in cycles per second (Hertz (Hz))

1 Hz

When a wave travels from one place to another, what is transported?

Energy

Assume that you have a periodic wave travelling down an infinitely long rope. What happens to the wavelength if you increase the period of this wave?

It decreases

If the fundamental frequency of a rope fixed at both ends is 30 Hz, the frequency of the second harmonic is ______

60 Hz

A long pendulum hanging from the ceiling of the classroom has a period of 8s. What is the frequency of this pendulum?

1/8 Hz

Node is the point of _______ displacement on a standing wave.

Maximum

A pure tone is always ______

sinusoidal

Sound waves are ______ waves

Longitudinal

Amount of inertia of an object is directly proportional to its ______

Mass

The 3rd harmonic is the ____ overtone

2nd

The rate at which work is done is called ______

Power

Mass reactance is greater at _____ frequencies

High

Stiffness reactance is greater at _____ frequencies

Low

An organ pipe is 1 meter long and is open at one end and closed at another. Which of the following is the frequency (to three significant digits) of one of the harmonics of the pipe? Assume that the speed of sound is 340 m/s.

255 Hz

In a tube open at one end, only ___ harmonics can be produced

Odd

Tube length and fundamental frequency are _____ proportional

Inversely

Three pure tones of frequencies 6 Hz, 4 Hz, and 3 Hz are played one at a time near a taut string of length 1 m that is tied at both ends. It is observed that only the 6 Hz tone makes the string vibrate in one of its allowed modes. From this information, can you deduce that

The lowest natural resonant frequency is 6 Hz

What structure provides the boundary between the middle and outer ear?

Tympanic membrane

What are the ossicles?

Small bones in the middle ear

Where is the tectorial membrane found?

Inner ear

The stereocilia are connected to each other through ______

Tip-links

What is the small bony chamber of the inner ear called?

Cochlea

Which inner ear membrane contains the organ of corti?

Basilar membrane

The _____ collects acoustic signals and funnels them to the eardrum

Pinna

What is the passageway leading from the nasopharynx to the anterior wall of the middle ear?

Eustachian tube

What are the functions of the middle ear?

Protection, impedance matching, and pressure equalization

The basilar membrane is ______ at the base than at the apex

Stiffer

Perilymph is present in the _______

Scala media

The middle and inner ear act as _______

Transducers

The outer ear resonances and middle ear impedance matching work together to effectively transmit sounds between ________

250 and 6000 Hz

What are the three membranes of the cochlea?

Tectorial, Reissner's, and Basilar

Which chambers does Reissner's membrane seperate?

Scala vestibuli and scala media

Which chambers does the basilar membrane seperate?

Scala media and scala tympani

Perilymph is high in ______

Sodium

Endolymph is high in ______

Potassium

What is the function of the stria vascularis?

Secretes endolymph in the cochlear duct.