Speech and Hearing Science Midterm (Units 1,2, and 3)

The membrane that makes up the surface of the Organ of Corti is the \________.

Reticular Lamina.

The function of the Eustachian tube is to\___________:

equalize the pressure in the middle ear.

The membrane to which the stapes footplate is attached is the \________.

Oval Window.

The membrane that has the tallest stereocilia of the outer hair cells embedded in it is the \__________.

Tectorial Membrane.

The boundary between the scala media and the scala vestibuli is the \________.

Reissner's Membrane.

Contraction of the stapedius pulls the \__________ in the \_______ direction.

Posterior crus of stapes; posterior.

The membrane that is rich in blood vessels and generates in electrical potential is the \_________.

Stria Vascularis.

Endolymph is high in \_________ and perilymph is high in \__________.

Potassium; sodium.

When activated, the middle ear muscle reflex causes a(n) \__________.

Reduction in transmission of low frequency sounds.

The \__________ part of the temporal bone is dense and contains the cochlea, and the \__________ part is filled with air-spaces.

Petrous; mastoid.

The resonance of the external ear (due to pinna, concha, canal, etc.) \_____________:

Amplifies frequencies from about 2000 to about 5000 Hz in adults.

The membranous labyrinth is filled with \___________:

Endolymph.

The arrangment of the VIIIth nerve fibers emerging from the cochlea is \_______:

Tonotopic with the highest frequencies on the outside and lowest frequencies on the inside.

The Type 2 (outer spiral) afferent neural fibers in the cochlea are arranged so that \_______:

Each fiber synapses with multiple outer hair cells.

After leaving the Organ of Corti, the fibers of the auditory nerve join together and form a trunk in the \_________.

Modiolus.

With the exception of the \____________, the pinna has a core of \___________.

Lobule; cartilage.

The membrane at the entrance to the scala tympani is the \_________.

Round Window.

The opening at the apex of the cochlea through which the scala tympani and scala vestibuli communicate is the \_________:

Helicotrema.

The configuration of the tympanic membrane in the ear canal may be described as \_______:

Concave (central portion most medial) and tilted.

The tensor tympani muscle is innervated by cranial nerve \__________:

V.

The three mechanisms of impedance matching by the middle ear are \_______:

Area ratio (thumbtack principle), ossicular lever, and buckling effect.

The cochlea contains about \________:

27,000 type I (radial) afferent fibers and 3,000 type II (spiral) afferent fibers.

The stapedius muscle is innervated by cranial nerve \______:

VII.

Two of the functions of the middle ear are \________:

Impedance matching, pressure equalization.

The membrane at the entrance to the scala vestibule is the \_________.

Oval Window.

The stereocilia of the hair cells are connected by \________ made of \________:

Tip links or cross links; protein fibers.

The functions of the outer ear are \________:

Protection, localization, amplification.

Perilymph is found in the \___________.

Scala Vestibuli and Scala Tympani.

On Planet Zorg, the resident aliens have a tympanic membrane with an area of 500 square millimeters and a stapes footplate with an area of 5 square millimeters. As a result, the pressure of an incoming sound wave \___________.

Increases by a factor of 100.

The number of inner hair cells and outer hair cells in a human ear is about \________:

3,500 inner and 12,000 outer.

The binaural cues for localization of sounds include \_________:

Interaural time/phase differences of low-frequency sounds and interaural intensity differences of high-frequency sounds.

The smallest muscle in the human body is the \_______ which is only \_____ mm long.

Stapedius - 6.

The role of the human pinna in monaural sound localization consists of \________:

Resolving front-back confusions and localizing sounds vertically, above and below the horizontal plane.

In response to low and moderate level sounds, the stapes \_________.

Moves with a rocking motion like a swinging door.

The head shadow effect allows us to localize sounds based on \_________.

Interaural intensity differences of high frequencies.

Which of these is not a theory of the middle ear muscle (acoustics) reflex?
-protects the middle and inner ear.
-reduces bone-conducted sound when speaking.
-creates distortions to amplify sounds.
-helps to prevent ossicular joints from flexing at high levels.
-none of the above.

Creates distortions to amplify sounds.

The \_________ hair cells are cylindrical in shape and have about \_______ stereocilia.

Outer; 100-150.

The rapid neural conduction that takes place when a neuron has an insulating layer is called _________ conduction.

Saltatory.

As one goes from base to apex, the \________ hair cells systematically get \________ and their stereocilia get \_______.

Outer; taller; taller.

The basilar membrane is about \________ times wider at the \_______ of the cochlea than at the \_______ of the cochlea.

3; apex; base.

The Type 1 afferent neural fibers in the cochlea are arranged so that \________.

About 8 fibers synapse with each inner hair cell.

Contraction of the tensor tympani pulls the \________ in the \______ direction.

Malleus; anterior.

Endolymph is found in the \______.

Scala media.

The inner ear contains \_____ row(s) of inner hair cells and \______ row(s) of outer hair cells.

1;3, but can be 4 or 5 in places.

The outer hair cells have \_____ rows of stereocilia of varying heights. The rows are arranged so that the shortest stereocilia are closest to the \______.

3;modiolus.

The probability of a neural firing depends on \______:

-The amount of neurotransmitter it receives across the synapse.
-The amount of depolarization of the post-synaptic membrane.

The membrane that separates the scala vestibuli and the scala media.

Reissners Membrane.

The fold of collagen-rich fold tissue from which the tectorial membrane arises.

Spiral Limbus.

The tissue that connects the basilar membrane to the lateral wall of the cochlea.

Spiral Ligament.

The membrane that is the surface of the Organ of Corti.

Reticular Lamina.

The membrane that sits above the Organ of Corti and has the tips of the tallest stereocilia of the outer hair cells embedded in it.

Tectorial Membrane.

The membrane at the entrance to the scala tympani.

Round Window

-The membrane at the entrance to the scala vestibuli.
-The membrane to which the stapes footplate is attached.

Oval Window.

The membrane that separates the scala media and the scala tympani.

Basilar Membrane.

The membrane on the lateral wall of the scala media that is rich in blood vessels.

Stria Vascularis.

To determine the elevation of a sound source, \______ are used. The ability to perform this task develops at about the age of \_______.

Monaural cues from the pinna and concha; 18 months.

The eighth nerve contains about \_______ afferent nerve fibers. About \______ percent of these fibers are the Type I fibers that connect directly with the inner hair cells.

30,000; 85-95.

On Mars, the resident aliens have a tympanic membrane with an area of 500 square millimeters and a stapes footplate with an area of 1 square millimeter. As a result, the pressure of an incoming sound wave \______.

Increases by a factor of 500.

Which of these functions can NOT be performed by a single ear, and instead requires the involvement of two ears working together: \______.
-localizing sounds in the horizontal plane based on the head shadow.
-resolving front-back confusions.
-determination of elevation of sounds, above and below the horizontal plane.

Localizing sounds in the horizontal plane based on the head shadow.

Each outer hair cell is supported by a(n) \______ cell. These cells have phalangeal processes that help to make up \_____.

Dieters; reticular lamina.

The mechanism of bone conduction that involves ALL parts of the air conduction pathway and can be heard when the ear is occluded is the \_____:

Osteotympanic.

Loss of outer hair cells results in a loss of \_____:

Sensitivity and Frequency Selectivity.

Which of the following phenomena are not explained by the place theory?
-tonotopic organization.
-the missing fundamental effect.
-our excellent discrimination of very low frequencies.

The missing fundamental effect; Our excellent discrimination of very low frequencies.

The representation of sounds in the central auditory nervous system is \_____:

Unilateral at lower levels, but bilateral and mostly contralateral starting at the level of the superior olivary complex.

The ossiculo-inertial mechanism of bone conduction involves \______:

Movement of the ossicular chain relative to the vibrating skull.

Wever's original volley theory suggested that \______; we now know that \_____:

Organized groups of fibers take turns firing on sequential peaks of the stimulus; on average, some neurons fire on every peak as long as the frequency is below about 4,000 Hz.

The inner hair cell response is related to basilar membrane \______ and the outer hair cell response is related to basilar membrane \______.

Velocity; displacement.

The Type 1 afferent neural fibers in the cochlea are arranged so that \______.

About 8 fibers synapse with each inner hair cell.

The frequency that gives as the largest response of the basilar membrane with the least amount of sound is the \______ of that location.

Best frequency.

The rapid growth of loudness in a person with cochlear hearing loss \_____:

Is called loudness recruitment; Results from loss of the tips on the tuning curves of the hair cells.

From the thalamus, information is sent to the \______.

Auditory cortex on the same side.

The osteotympanic mechanism of bone conduction involves \______:

Generation of sound in the ear canal by shaking the canal walls.

The information carried by the eighth nerve from the right cochlea goes to \_____:

The right cochlear nucleus.

Deflection of the stereocilia away from the modiolus causes \______:

"Trap doors" on the stereocilia to be open more of the time; Ions to diffuse into the hair cells; The hair cells to release neurotransmitter.

The Type 2 (outer spiral) afferent neural fibers in the cochlea are arranged so that \_____:

Each fiber synapses with multiple outer hair cells.

The dynamic range of a neuron is the \______:

Range of levers over which its firing rate increases linearly with the stimulus level.

The functions of the inner ear are \_____:

Filtering, distribution, transduction.

The level of the auditory nervous system at which the middle ear muscle reflex is mediated is the \______:

Superior olivary complex.

The tonotopic organization of the cochlea results primarily from the \_____:

Fact that the basilar membrane is narrow (and therefore stiff) at the base, and wide (and therefore flaccid) at the apex.

Modern theories of pitch perception are based on phase locking at \______ frequencies, a place code at \______ frequencies and both mechanisms working together at the \______ frequencies.

Low; high; middle.

The dominant mechanism of bone conduction, and the only mechanism that does NOT involve any part of the air conduction pathway is \_____:

Compressional/distortional.

Within the cochlea, the traveling waves due to low frequencies peak near the \______, while those due to high frequencies peak closer to the \_____.

Apex; base.

The cochlear microphonic is a(n) \______:

AC receptor potential, probably due to the outer hair cells.

The level of the auditory nervous system at which we form a three-dimensional representation of the world of sounds, or soundscape, is the \_____:

Auditory cortex.

The inner hair cells \______, while the outer hair cells \_____:

Relay sensory information to the eighth nerve; create the cochlear amplifier.

The movement of the traveling wave results in shearing motion and deflection of the stereocilia because \______:

the basilar membrane is attached at its edges, causing the greatest displacement at the center.

The full dynamic range of human hearing is covered by \_____.

A combination of three different types of Type 1 neural fibers, with different spontaneous firing rates and dynamic ranges.

The refractory period is \______:

The time that a neuron that has just fired to needs to prepare to fire again; about 1 msec.

The resting potential in the scala media is the \_____ and it is generated by the \______.

Endocochlear potential; stria vascularis.

If two tones presented with a distortion product otoacoustic emission system have frequencies of 1,000 and 1,200 Hz, the dominant distortion product otoacoustic emission that will result will be at \_______ Hz.

800

The whole nerve action potential is the \_____:

sum of the spike responses of multiple neural fibers.

If a strong transient-evoked otoacoustic emission is recorded in response to click stimuli, which of the following is/are true?
-the person's exact hearing thresholds can be determined from the data.
-the auditory system is functioning up through the level of the cochlear outer hair cells, with at most a mild hearing loss.
-the auditory system is functioning up through the level of the cochlear outer hair cells, with no hearing loss.

the auditory system is functioning up through the level of the cochlear outer hair cells, with at most a mild hearing loss.

A basilar membrane tuning curve tells you \________:

how much sound is needed to get a fixed displacement of the basilar membrane as a function of frequency.

The summating potential is a(n)\_____:

DC receptor potential, probably due to both inner and outer hair cells.

The level of the auditory nervous system at which the inner ear reflex is mediated is the \______:

superior olivary complex.

According to recent measurements, the tuning of the basilar membrane is \_____:

comparable in sharpness to neural tuning.

Loss of inner hair cells results in loss of \_____:

sensitivity.

The dynamic range of an individual neural fiber is \_____:
-less than the dynamic range of hearing.
-the difference between its spontaneous firing rate and its maximum firing rate.
-the range of levels over which its firing rate increases as level increases.

-less than the dynamic range of hearing.
-the range of levels over which its firing rate increases as level increases.

Which of the following is NOT thought to result from the electromotility of the outer hair cell in a healthy, live cochlea?
-cochlear nonlinearities.
-otoacoustic emissions.
-enhanced frequency selectivity of the basilar membrane.
-generation of the cochlear microphonic.
-reduced sensitivity of the basilar membrane.

reduced sensitivity of the basilar membrane.

The intensity of a sound wave determines its perceived \_____, which is described by the \_____ scale.

loudness; phon or sone.