Term
| The difference limen for intensity ???? for intensities above 50db |
|
Definition
|
|
Term
| ???? is defined as the masking that occurs when the masker and probe are present at the same time. |
|
Definition
|
|
Term
| The bandwidth of the ???? determine how well we can detect speech in noise. |
|
Definition
|
|
Term
| The ???? threshold for the signal or probe when presented without the masker. |
|
Definition
|
|
Term
| ???? refers to our ability to place a sound source in space. |
|
Definition
|
|
Term
| The reverberation time of a typical class room will ???? if the number of people in the room doubles. |
|
Definition
|
|
Term
| Reverberation tends to mask the ???? segments of speech. |
|
Definition
|
|
Term
| Diffraction is more pronounced with ???? wavelengths. |
|
Definition
|
|
Term
| Interaural intensity differences for sound localization are mostly useful in ???? frequencies. |
|
Definition
|
|
Term
| The reverberation time is the time interval in which the reverberating sound, due to decaying refractions reaches ???? of its initial value. |
|
Definition
|
|
Term
| The inverse square law states that in a free field, the sound pressure will decrease by ???? for every doubling of distance. |
|
Definition
|
|
Term
| The ???? effect describes our ability to use redundant information for better performance when the same signal arrives at both ears even if one has a bad SNR |
|
Definition
|
|
Term
| The ???? will improve our hearing by 3, 6, or 9 dB. |
|
Definition
| binaural advantage effect |
|
|
Term
| Interaural ???? differences are extracted in the lateral superior olivary complex. |
|
Definition
|
|
Term
| Neither ITD nor ILDs are good between ???? and ???? |
|
Definition
|
|
Term
| Interaural ???? differences are primarily used in low frequencies. |
|
Definition
|
|
Term
| The ???? components of reverberations are those that arrive soon enough to be integrated with the direct signal. |
|
Definition
|
|
Term
| ???? can partially restore sensation of hearing by bypassing the usual auditory pathway & by stimulating the auditory nerve directly. |
|
Definition
|
|
Term
| What is the primary reason we need a middle ear? |
|
Definition
| To overcome the energy loss at the stapes footplate - cochlea boundary |
|
|
Term
| How much boost is given by the area ratio? |
|
Definition
|
|
Term
| The stapes' footplate sits on which of the windows? |
|
Definition
|
|
Term
| The structures primarily responsible for the transfer function of the external ear are... |
|
Definition
| concha, ear canal, and ear drum |
|
|
Term
| Pros of the constant stimuli method |
|
Definition
| easy to administer, can provide precise estimate of threshold |
|
|
Term
| What are 3 common methods for estimating thresholds? |
|
Definition
| method of limits, method of constant stimuli and the method of adjustment |
|
|
Term
| Cons of method of adjustment |
|
Definition
| Results can be unreliable and biased |
|
|
Term
| Pros of method of adjustment |
|
Definition
| easy to administer, intuitive, and appealing to the subject |
|
|
Term
| A wave transports ???? without transporting ???? |
|
Definition
|
|
Term
| What is the range of frequencies that humans are capable of hearing? |
|
Definition
|
|
Term
|
Definition
| A particular point in the cycle of a sine wave that is measured as an angle, it is important for comparing waves helps localization |
|
|
Term
| What is the formula for period? |
|
Definition
|
|
Term
| What is the formula for frequency? |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
| quantifies how often the particles of the medium vibrate when a wave passes through (Hz) |
|
|
Term
| Simplest form of sound is a ???? |
|
Definition
|
|
Term
| What is the method of adjustment? |
|
Definition
| Similar to the method of limits except that the subject controls the stimulus. Gradually adjust the level instead of moving in discrete steps. Use both ascending and descending runs until can or can't hear. |
|
|
Term
|
Definition
| False responses may cause errors in estimating threshold. May miss true threshold if step size is too big. |
|
|
Term
| A doubling in intensity is ????. |
|
Definition
|
|
Term
| A doubling of sound pressure ????. A ten fold increase equals ???? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Mechanisms responsible for frequency effect on absolute threshold |
|
Definition
| External and middle ear boost frequency. Cochlea doesn't effect auditory curve much but contributes to how sensitive we are overall |
|
|
Term
| Lower and higher frequencies requires progressively ???? sounds |
|
Definition
|
|
Term
| At about 50 years old a significant decline occurs at ???? hz and above |
|
Definition
|
|
Term
| At 18 years old high frequencies begins to decline due to hair cell atrophy at the ???? of the cochlea. |
|
Definition
|
|
Term
| Females have about ???? better thresholds than males. |
|
Definition
|
|
Term
| The lateral ???? of the external ear canal is cartilage. (hair and cerumen) The medial ???? is bone with a thin layer of skin. |
|
Definition
| 1/3 laterally 2/4 medially |
|
|
Term
| The frequency of speech is... |
|
Definition
|
|
Term
| What is the threshold of pain? |
|
Definition
|
|
Term
| What is the difference in dB between MAP and MAF? |
|
Definition
| about 6 dB due to calibration differences between transducers, heady/body diffraction effects (low frequencies), ear canal/concha resonances (high frequencies) |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Minimum auditory pressure |
|
|
Term
| How does one test for absolute threshold? |
|
Definition
| measured in quiet. Task is to distinguish sound from no sound. Frequency and duration of sound influence absolute threshold. |
|
|
Term
| Absolute threshold is the same as ???? |
|
Definition
|
|
Term
| Method of constant stimuli can identify yes bias by using ???? but is still susceptible to no bias. |
|
Definition
|
|
Term
| Method of limits and adjustments are susceptible to ???? and ???? bias. |
|
Definition
| yes (aggressive) and no (passive) |
|
|
Term
| Problems with classical methods |
|
Definition
| when the sound is near threshold it is hard to tell the difference between sound and no sound. People use evidence their ears and brain provide but whether they say yes or no depends on how much they like to say yes |
|
|
Term
| How is threshold defined in psychophysics? |
|
Definition
| stimulus that produces an arbitrary but defined level of performance. Can be changed based on indicator of performance. |
|
|
Term
|
Definition
| lowest point able to hear; smallest stimulus when some one has hearing loss they have elevated thresholds |
|
|
Term
| What characteristics define a complex periodic wave? |
|
Definition
| multiple sine waves, has fundamental frequency, harmonics and repeating period |
|
|
Term
| What is a fundamental frequency? |
|
Definition
| the largest common denominator of a group of component frequencies |
|
|
Term
| What is a longitudinal wave? |
|
Definition
| A wave in which particles are displaced parallel to the direction of the wave. |
|
|
Term
|
Definition
| the whole multiples of the fundamental frequency |
|
|
Term
| What is the boost given by binaural summation? |
|
Definition
|
|
Term
| What causes binaural summation? |
|
Definition
| central auditory system sums up responses from both ears; they are not independent |
|
|
Term
| Where are the electrical pulses of each ear summed together? |
|
Definition
|
|
Term
|
Definition
| two ears; involving the use of both ears |
|
|
Term
| 3 advantages of binaural hearing |
|
Definition
| binaural summation, binaural squelch and sound localization |
|
|
Term
|
Definition
| the time it takes for sound to travel to the opposite ear |
|
|
Term
| What are 2 interaural differences or cues for localization? |
|
Definition
| Interaural time difference (ITD) and interaural intensity difference (IID or ILD) |
|
|
Term
|
Definition
| location on the median or vertical plane. right in front of the face is 0 degrees elevation |
|
|
Term
|
Definition
| location on horizontal or left/right plane. something pointed directly at the right ear is at 90 degrees azimuth |
|
|
Term
| What are the two aspects of sound localization? |
|
Definition
|
|
Term
| What is sound localization? |
|
Definition
| Knowing where a sound is coming from based exclusively on the sense of hearing |
|
|
Term
| What is a non-sinesoidal wave? |
|
Definition
| more complicated than a sine but still has a repeating pattern |
|
|
Term
| What are the two kinds of complex auditory stimuli? |
|
Definition
| complex periodic and complex a periodic waves |
|
|
Term
| Intensity level of loudest sound... |
|
Definition
| IL max = 1 watt/m squared. Can hear louder but will cause damage |
|
|
Term
|
Definition
| complex; composed of multiple sines |
|
|
Term
| Waves are classified according to... |
|
Definition
| the direction of vibration of the medium relative to the direction the wave is moving |
|
|
Term
| What is a transverse wave? |
|
Definition
| the direction the particles travel is perpendicular to the direction of the wave |
|
|
Term
| Does intensity discrimination follow weber's law? |
|
Definition
| no at least not for sound levels below 50 dB |
|
|
Term
| Inner hair cells receive ??? of the afferent innervation of the cochlea. |
|
Definition
|
|
Term
| The ???? potential or cochlear microphonic is produced by ions flowing into and out of hair cells |
|
Definition
|
|
Term
| What are the functions of the external ear? |
|
Definition
| assist in localizing and collecting sound |
|
|
Term
| Cons of constant stimuli method |
|
Definition
| need to know threshold in advance to center values, lots of trials, time might be wasted if just want threshold |
|
|
Term
| What is the method of limits? |
|
Definition
| Adaptive method, start with level that you think listener will hear. If hears #1; lower. If hears #2; lower. Repeat either from where easily heard or can't hear. Threshold estimated from where response changes |
|
|
Term
| When the efferent system is active, what occurs? |
|
Definition
| gain of the cochlear amplifier is reduced |
|
|
Term
| What is physiologic noise? |
|
Definition
| noise made by processes such as respiration, cardiovascular function and digestion; mostly low frequency interferes with hearing low frequencies |
|
|
Term
| Changing duration of sound influences our ability to hear it for durations less than ???? |
|
Definition
|
|
Term
| Duration and intensity can change but ???? won't |
|
Definition
|
|
Term
|
Definition
| efficient because can "focus" stimuli; near threshold gives threshold in fewer trials, don't need to know threshold |
|
|
Term
| Absolute threshold is primarily determined by responses of ???? auditory system |
|
Definition
|
|
Term
| What is the formula for temporal integration? |
|
Definition
| energy = intensity x time |
|
|
Term
| What is a differential threshold? |
|
Definition
| The difference between two stimuli that is necessary for the subject to say they are just different (aka just noticeable difference or difference limen) |
|
|
Term
|
Definition
| The just noticeable difference of a stimulus divided by the stimulus is a constant |
|
|
Term
| What accounts for the large discrepancy between the basilar membrane tuning curves obtained from von Bekesy's data and tuning curves obtained from auditory nerve fibers? |
|
Definition
| the outer hair cells didn't work because he recorded responses of cadavers |
|
|
Term
| The mapping of frequency to place along the cochlea is known as |
|
Definition
|
|
Term
| When making measurements of basilar membrane diplacement for a fixed location on the basilar membrane the input frequency that produces a maximum displacement for that location would correspond to what point on the tuning curve. |
|
Definition
| the tip of the tuning curve |
|
|
Term
| ???? hair cells receive afferent innervation while ???? hair cells receive efferent innervation. |
|
Definition
|
|
Term
| The consequence of the active function of the outer hair cells is to |
|
Definition
| sharpen tuning and make thresholds better |
|
|
Term
| What is Weber's fraction? |
|
Definition
| change in I divided by I equals a constant |
|
|
Term
| What are the 2 Weber's Law equations? |
|
Definition
| change in I divided by I equals a constant and constant times I equals the change in I |
|
|
Term
| What is on the Y axis for a weber's law graph with a reverse ski slope with I on the x axis? |
|
Definition
|
|
Term
| What is on the y axis for a weber's law graph with a flat line with I on the x axis? |
|
Definition
|
|
Term
| Does frequency discrimination support Weber's law? |
|
Definition
| only between 1000 and 2000 hz. Doesn't hold for high or low frequencies |
|
|
Term
| If duration of a sound is increased by a factor of 10; the threshold of the sound decreases by .... |
|
Definition
|
|
Term
| The collection of cell bodies that form the auditory nerve is called the... |
|
Definition
|
|
Term
| The inside of the hair cell has ???? charge relative to the endolymph. |
|
Definition
|
|
Term
| Why is the round window important for the function of the cochlea? |
|
Definition
| the round window bulges out when the stapes pushes in, allowing the traveling wave to occur |
|
|
Term
| The traveling wave for a 200Hz tone will peak near the cochlear ???? while an 8000Hz tone will peak near the cochlear ???? |
|
Definition
|
|
Term
| The movement of the stereocilia of the hair cells is called... |
|
Definition
|
|
Term
| Stereocilia play a role in cochlear transduction. Deflection of stereocilia in the excitatory direction occurs on which phase of the stimulating wave form |
|
Definition
|
|
Term
| Phase locking in the action potentials of the auditory nerve response is probably a cue for the perception of... |
|
Definition
|
|
Term
| It is believed that positively charged ions flow into the hair cell through channels on the... |
|
Definition
| stereocilia of the hair cells |
|
|
Term
| The point along the basilar membrane at which the peak of the traveling wave occurs for a specific stimulus frequency is largely determined by... |
|
Definition
| changes in width and stiffness along the basilar membrane |
|
|
Term
| What is the formula for intensity difference threshold? |
|
Definition
| change in intensity level equals 10 log10 times change in I plus I1 divided by I1 if the measurement is in watt per meter square |
|
|
Term
| Air is able to transmit sound because it has both ???? and ???? |
|
Definition
|
|
Term
|
Definition
| the ability to resist changes in shape and volume when force is applied to it |
|
|
Term
|
Definition
| the result of vibration of air molecules creating a sound wave and pressure changes in the wave lead to auditory sensation |
|
|
Term
|
Definition
| a disturbance that travels through a medium from one location to another |
|
|
Term
| When we say that the outer hair cells are motile we mean they... |
|
Definition
| change their length in response to sound stimulation |
|
|
Term
| Lower frequencies are coded in fibers closer to the ???? of the auditory nerve while higher frequencies are coded closer to the ????. |
|
Definition
|
|
Term
| What is a characteristic of the acoustic reflex that suggests it may not be effective at protecting the ear from loud sound? |
|
Definition
| latency of the reflex is about 40 -150 msec |
|
|
Term
| What are the characteristics of inner hair cells? |
|
Definition
| one cell receives many afferent Type I fibers and afferent fiber terminals contact the cell body, flask shaped, many cells receive few efferent fibers and they contact the afferent fibers |
|
|
Term
| What are the characteristics of outer hair cells? |
|
Definition
| Cylindrical shape, many cells receive majority of the efferent fibers and terminals contact the cell body. Many cells receive few afferent Type II fibers and they contact the cell body |
|
|
Term
| Which structure is most appropriately called the cochlear amplifier? |
|
Definition
|
|
Term
| Formula for sound intensity |
|
Definition
| dBIL equals 10 log10 times I sub O divided by I sub R |
|
|
Term
| Over which frequency range does the transfer function of the middle ear result in the most efficient transfer of energy to the cochlea? |
|
Definition
|
|
Term
| Outer hair cells are supported by... |
|
Definition
| deiter's cells via the phalangeal process |
|
|
Term
| Endolymph is found within the... |
|
Definition
|
|
Term
| Perilymph is found in the... |
|
Definition
| scala vestibuli and scala tympani |
|
|
Term
| The cell body of which type of hair cell is completely surrounded by supporting cells? |
|
Definition
|
|
Term
| What is the length of the external ear canal? |
|
Definition
|
|
Term
| I sub R is always equal to |
|
Definition
|
|
Term
| What is the threshold of hearing? |
|
Definition
|
|
Term
| What is the size of the tympanic membrane? |
|
Definition
|
|
Term
| What are the three layers of the tympanic membrane? |
|
Definition
| Outer layer (squamous cell epithelial): bound the external ear medially. Middle layer (fibrous) lies in between and gives membrane its shape and consistancy. Composed of circumferential fibers and radial fibers. Inner layer (mucosal) bounds middle ear laterally |
|
|
Term
| Formula for sound pressure |
|
Definition
| SPL(dB) = 20 log10 times (p sub O divided by p sub R |
|
|
Term
| What are the 3 decibel scales? |
|
Definition
| dB - a relative scale; the ratio of two quantities. dB SPL - A fixed dB scale referenced to a known pressure of 20 micropascals. dB HL - A fixed dB scale fixed to normal hearing sensitivity. |
|
|
Term
| What represents the time domain? |
|
Definition
| Waveform: shows instantaneous amplitude on the y axis and time on the x |
|
|
Term
| What represents the frequency domain? |
|
Definition
| Spectrum: shows amplitude spectrum on y axis and frequency on x |
|
|
Term
| What does a spectrogram represent? |
|
Definition
| Amplitude, frequency and time |
|
|
Term
| What is the bandwidth of a narrow band spectrogram? |
|
Definition
|
|
Term
| What is the bandwidth of a broad band spectrogram? |
|
Definition
|
|
Term
| The ???? hair cells are located away from the modiolus, while the ???? hair cells are located closer to the modiolus. |
|
Definition
|
|
Term
|
Definition
| quantity & the amount of matter |
|
|
Term
|
Definition
| proportional to change in intensity caused by sound waves. The maximum amount of displacement along y axis. Cannot be less than zero |
|
|
Term
| The ???? the amplitude the more intense the sound. |
|
Definition
|
|
Term
| According to Weber's law the more ???? something is the ???? the change needed to notice change |
|
Definition
|
|
Term
| Does temporal discrimination obey weber's law? |
|
Definition
|
|
Term
| What are the characteristics of a complex aperiodic wave? |
|
Definition
| Frequencies are random, does not have a period, no distinct fundamental frequency, no harmonics |
|
|
Term
| True or False: Intensity diminishes the further away you are from the source |
|
Definition
|
|
Term
| Intensity level of faintest sound is |
|
Definition
| IL min = I sub R 10 to the -12 watts per meter square |
|
|
Term
| What is the intensity of a sound wave? |
|
Definition
| The amount of energy that is transported past a given area of the medium per unit of time measured in watts per meter square |
|
|
Term
| Severing loss is between ??? and ???? |
|
Definition
|
|
Term
| 3 types of noise induced hearing loss |
|
Definition
| Temporary threshold shift, permanent threshold shift, acoustic trauma |
|
|
Term
| Profound hearing loss is ???? dB |
|
Definition
|
|
Term
| What is temporary threshold shift? |
|
Definition
| A shift in absolute threshold that returns in time to pre-exposure levels. Time depends on level and duration of sound. |
|
|
Term
| Thresholds between ???? and ???? kHz are most effected by TTS because of the 4K notch effect. |
|
Definition
|
|
Term
| What is permanent threshold shift? |
|
Definition
| Hearing level change that has become persistent and unlikely to improve |
|
|
Term
| What is the maximum dose of noise allowed by OSHA? |
|
Definition
|
|
Term
| ITDs are shortest when a sound is at ???? or ???? degrees azimuth? |
|
Definition
|
|
Term
| ITDs are longest when a sound is played at ???? or ???? degrees azimuth? |
|
Definition
|
|
Term
| The effect of ITD depends on 2 things. What are they? |
|
Definition
| angle of incidence and size of head |
|
|
Term
| ITDs are frequency independent but are more useful at ???? frequencies? |
|
Definition
|
|
Term
| At greater than 35 dB SPL the difference in sound loudness is ???? dB. (monaural vs binaural) |
|
Definition
| 6 dB; monaural 56 dB SPL tone would be judged as equally loud as a binaural tone of 50 dB |
|
|
Term
| What is the purpose of two hear hearing? |
|
Definition
| spatial hearing and understanding |
|
|
Term
| Binaural summation of loudness means that a sound is ???? as loud when presented binaurally vs monaurally. |
|
Definition
|
|
Term
| Improvement in hearing threshold when compared to monaural hearing is ???? at threshold, ???? 50 dB, and ???? at 90 dB. |
|
Definition
|
|
Term
| What is binaural squelch? |
|
Definition
| The binaural advantage from adding the ear with the poorer signal to noise ratio compared to just listening with the better SNR ear alone. 2 is always better. |
|
|
Term
| People can discriminate changes in frequency as small as ???? Hz for frequencies between 500 Hz and 1000 Hz. |
|
Definition
|
|
Term
| The ???? is the detection threshold for sound in a sound field. |
|
Definition
| Minimum audible field (MAF) |
|
|
Term
| In the auditory system, transduction refers to the change from ???? to ????. |
|
Definition
| acoustic energy to neural activity |
|
|
Term
| The basilar membrane is ???? at the base than at the apex of the cochlea. |
|
Definition
|
|
Term
| Deiter's cells completely surround the ???? hair cells. |
|
Definition
|
|
Term
| outer hair cells sit on top of the Deiter's cells and are only supported by the ????. |
|
Definition
|
|
Term
| Sound waves are longitudinal or transverse? |
|
Definition
|
|
Term
| The near miss to Weber's law refers to the fact that the intensity difference limen is almost a constant proportion of the standard intensity but it is ???? than it should be for high intensities. |
|
Definition
|
|
Term
| Temporal discrimination obeys or disobeys Weber's Law? |
|
Definition
|
|
Term
| The method of ???? is a psychophysical method for estimating threshold in which a fixed set of stimuli is presented in random order. |
|
Definition
| method of constant stimuli |
|
|
Term
| Complex periodic waves do or do not have a fundamental frequency? |
|
Definition
|
|
Term
| The ratio of the pressure of a sound with -20 dB SPL to the pressure of a sound with 0 dB SPL is 10. True or False? |
|
Definition
|
|
Term
| In clinical audiology dB HL values are always relative to the ???? sounds that a healthy young individual ought to be able to hear. |
|
Definition
|
|
Term
| Suppose that a stimulus is 10 dB IL and this is 100x as intense as a sound wave with -10 dB IL. Then you could assume that a 90 dB sound is 100x as intense as a ???? dB sound. |
|
Definition
|
|
Term
| The auditory system is sensitive to ???? dB intensity changes across a broad range of intensities. |
|
Definition
|
|
Term
| There are 3 times as many ???? hair cells as ???? hair cells. |
|
Definition
|
|
Term
| 2 functions of the cochlea are... |
|
Definition
| spectral analysis and transduction of sound |
|
|
Term
| What is the primary reason we need a middle ear? |
|
Definition
| To over come the loss of energy at the stapes footplate - cochlea boundary |
|
|
Term
| Which two auditory structures determine the shape of the human audibility curve? |
|
Definition
| The external and middle ear |
|
|
Term
| The scala vestibule and scala tympani, tunnel of corti, cell bodies of OHCs and the space between the membranous labyrinth and osseous labyrinth contain... |
|
Definition
|
|
Term
| Which part of the tympanic membrane lacks the fibrous layer and contains only two layers? |
|
Definition
|
|
Term
| When the efferent system is active the gain of the cochlear amplifier is ????. |
|
Definition
|
|
Term
| The point along the basilar membrane as which the peak of the traveling wave occurs for a specific stimulus is largely determined by... |
|
Definition
| The changes in width and stiffness along the basilar membrane |
|
|
Term
| Why is the acoustic reflex not effective at protecting the ear from loud sound? |
|
Definition
| The latency of the reflex is 40-150 msec |
|
|
Term
| Doubling a sound pressure causes a dB change of... |
|
Definition
|
|
Term
| The process by which the ear summates energy over time is called... |
|
Definition
|
|
Term
| Another name(s) for the difference limen is... |
|
Definition
| Just noticeable difference or differential threshold |
|
|
Term
| How many times less intense is a sound with an intensity level of -10 dB when compared to a sound of 0 dB IL? |
|
Definition
|
|
Term
| The difference limen for frequency ???? for frequencies above 1000 Hz. |
|
Definition
|
|
Term
| Maggie's threshold of detection for a 3000 Hz pure tone is 15 dB SPL when measured using headphones. What would happen to the threshold if presented through loud speakers? |
|
Definition
|
|
Term
| If the duration of a sound is increased by a factor of 10, the threshold of the sound decreases by about ???? |
|
Definition
|
|
Term
| For what sounds does Weber's law for intensity discrimination hold true? |
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Definition
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Term
| If the quiet threshold is equal to 5 dB SPL and the masked threshold is also equal to 5 dB SPL then the amount of masking is... |
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Definition
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Term
| Moderately severe hearing loss is ???? to ???? dB. |
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Definition
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Term
| Binaural summation effect gives an advantage of up to ???? and the Binaural squelch gives an advantage of up to ????. |
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Definition
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Term
| Slight hearing loss is ???? to ???? dB. |
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Definition
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Term
| Mild hearing loss is ???? to ???? dB. |
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Definition
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Term
| Moderate hearing loss is ???? to ???? dB. |
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Definition
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Term
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Definition
| The head shadow effects the level of the sound. Sound level in the opposite ear is smaller |
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Term
| The effect of ILD depends on frequency. The effect is ???? for low frequencies and ???? for high frequencies. |
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Definition
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Term
| Why are low frequency sounds diffracted around the head? |
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Definition
| Low frequency sounds have long wavelengths compared to the size of the head and are therefore diffracted |
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Term
| Why are high frequency sounds reflected by the head? |
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Definition
| High frequency sounds have short wavelengths compared to the size of the head and are therefore reflected. |
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Term
| What is the duplex theory? |
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Definition
| The idea that we use 2 sets of cues for localization. ILD for high frequencies and ITD for low frequencies. |
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Term
| ITDs are extracted in the ???? |
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Definition
| medial superior olivary complex |
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Term
| ILDs are extracted in the ???? |
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Definition
| lateral superior olivary complex |
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Term
| What intensities are ITD cues best for? |
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Definition
| low frequencies below 1.5 kHz |
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Term
| What intensities are ILD cues best for? |
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Definition
| high frequencies above 3 kHz |
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Term
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Definition
| At 0 degrees we can detect change as small as 1 degree at 900 Hz performance drops above 1500 Hz |
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Term
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Definition
| Best performance is at 0 degrees and at 0 degrees intensity discrimination is equal to 1 dB but performance is worse below 3000 hz |
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Term
| Neither ITDs nor ILDs are good between ???? and ???? Hz. |
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Definition
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Term
| The reason that a sound is more intense on the side of the head closer to the sound source is because... |
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Definition
| The head reflects sound on the side closer to the sound source |
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Term
| What is the binaural summation or redundancy effect? |
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Definition
| describes the ability of the auditory system to use redundant information for better performance when the same signal arrives at both ears |
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Term
| What is binaural squelch? |
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Definition
| Advantage of adding the ear with the poorer signal to noise ratio compared to the ear with the better SNR alone |
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Term
| What is the head shadow effect? |
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Definition
| Advantage which occurs when the head obstructs sounds arriving at the ears from different locations. Allows the listener to always have available the ear with the better SNR (causes ILD) |
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Term
| ITDs and ILDs are useful for localizing frequencies in ????. |
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Definition
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Term
| Masked threshold for a signal can be much ???? when listening with two ears as compared with just one |
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Definition
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Term
| Quiet or unmasked threshold |
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Definition
| absolute threshold for the signal or probe when presented alone |
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Term
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Definition
| Threshold for signal or probe when presented with masker |
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Term
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Definition
| Difference between quiet threshold and masked threshold |
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Term
| What is binaural masking level difference? |
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Definition
| Improvement in detectability (loudness) of a signal which can occur under binaural listening conditions aka release from masking |
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Term
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Definition
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Term
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Definition
| homophasic; identical stimuli to both ears |
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Term
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Definition
| anitphasic; different stimuli to each ear |
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Term
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Definition
| diotic; signal/masker presented binaurally with no interaural differences |
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Term
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Definition
| monotic; signal/masker presented to only one ear |
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Term
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Definition
| dichotic; signal/masker presented to one ear 180 degrees out of phase relative to the other ear |
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Term
| monotic and diotic stimuli both produce ???? amount of masking. |
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Definition
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Term
| Dichotic combos produce ???? masking than for either the monotic or diotic masking conditions |
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Definition
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Term
| What is masking level difference? |
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Definition
| A measure of the improvement in detectability of a signal which can occur under binaural listening conditions |
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Term
| What is the formula for the amount of masking? |
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Definition
| amount of masking = masked threshold - quiet threshold |
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Term
| What happens when a monotic stimuli is followed by a dichotic (s sub m; m sub o) stimuli? |
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Definition
| The monotic stimuli will have a higher threshold than the dichotic condition. This shows that presenting sound to both ears makes it easier to hear the tone. |
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Term
| Adding out of phase noise to the second ear ???? the threshold. |
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Definition
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Term
| Monotic and diotic conditions both have a MLD of... |
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Definition
| 0 db. You can't hear the probe through the mask. |
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Term
| S sub m; M sub o conditions have a masking level difference of... |
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Definition
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Term
| S sub o; M sub pi conditions have a MLD of... |
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Definition
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Term
| S sub pi; m sub o conditions have a MLD of... |
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Definition
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Term
| The primary environmental effects on speech communication are ???? and ???? |
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Definition
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Term
| In any acoustic field that has reflective surfaces what phenomena always occur? |
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Definition
| Absorption, reflection (diffuse, non-diffuse), refraction, and diffraction |
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Term
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Definition
| when a sound wave meets an obstacle some of the sound/energy passes into the material where it is absorbed. |
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Term
| what is non-diffuse reflection? |
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Definition
| Occurs when sound strikes a hard, dense surface and is reflected at the angle of incidence (think of a light shining into a mirror) |
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Term
| What is diffuse reflection? |
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Definition
| when the shape of a surface scatters and redirects the sound so that it is heard in other parts of the space (light into a disco ball) |
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Term
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Definition
| a change in the direction of the waves as they pass from one medium to another (ie when traveling over water) |
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Term
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Definition
| A change in direction of waves as they pass through an opening or around a barrier |
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Term
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Definition
| The persistence of any sound in an enclosed space |
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Term
| What is the acoustic impulse response? |
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Definition
| The collection of multiple reflections of the sound that mask the direct sound |
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Term
| Early reflections are produced up to ???? |
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Definition
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Term
| Late reflections are produced up to ???? |
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Definition
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Term
| Really reflections are produced up to ???? |
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Definition
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Term
| What is reverberation time? |
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Definition
| The amount of time it takes the sound energy to reach one millionth of its initial value or 60 dB. |
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Term
| Reverberation has 2 effects on speech... |
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Definition
| Self masking (vowels) Overlap masking (consonants) |
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Term
| 4 common audiogram curves of people with hearing loss |
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Definition
| ski slope (high frequency loss), reverse ski slope (low frequency loss), cookie bite (mid-range loss), flat line |
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Term
| What is sensorineural hearing loss? |
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Definition
| problem lies in the vestibular or cochlear nerve, the inner ear or central processing centers of the brain |
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Term
| What is conductive hearing loss? |
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Definition
| Occurs when there is a problem conducting sound anywhere along the route through the outer ear, tympanic membrane or middle ear/ ossicles |
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Term
| What is mixed hearing loss? |
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Definition
| both conductive and sensorineural loss |
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Term
| Normal hearing loss is ???? to ???? dB |
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Definition
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