Review the Key to Symbols at the Bottom of Fig A821

• Journal List
• J Acoust Soc Am
• PMC2637535

J Acoust Soc Am. 2008 Jun; 123(half dozen): 4352–4357.

The outcome of a precursor on growth of forward masking^one

Received 2007 Sep ten; Revised 2008 Mar 25; Accepted 2008 Mar 31.

Abstract

This study examined the effect of an on-frequency precursor on growth-of-masking (GOM) functions measured using an off-frequency masker. The point was a 6-ms, 4-kHz tone. A GOM function was measured using a forty-ms, ii.8-kHz tone (the off-frequency masker). GOM functions were then measured with an on-frequency, fixed level precursor presented before the off-frequency masker. The precursor was 50 or 60 dB SPL, and 160 ms in duration. For the 60-dB SPL precursor, a 40-ms elapsing was as well used. Two-line functions were fit to the GOM data to gauge the basilar membrane input-output function. The precursors reduced the gain of the input-output function, and this subtract was graded with precursor level. Both precursor durations had the same consequence on gain. Changes in masking following a precursor were larger than would be predicted by additivity of masking. The observed subtract in gain may be consistent with activation of the medial olivocochlear reflex past the precursor.

INTRODUCTION

About sounds of interest are time varying in nature, then the response of the auditory organization must exist examined for dynamic also as steady signals. This response changes for a short period after the presentation of a sound. This sound will be chosen a precursor. If the forerunner is followed by a brusk-elapsing signal, it may increment the threshold for detecting the betoken, an event chosen frontward masking. If the signal is presented with a simultaneous masker, the forerunner may make the bespeak audible at a lower signal-to-masker ratio. This effect has been called overshoot (^{Zwicker, 1965a}) or the temporal result (^{Hicks and Bacon, 1992}). That is, in simultaneous masking, a forerunner may make a subsequent sound easier to hear, but in forward masking, a forerunner may accept the opposite effect. The point of this paper is to try to reconcile these two effects with i underlying mechanism.

The physiological bases of frontward masking are not well understood, and indeed, forward masking probably depends on processes at several levels of the auditory organization. One hypothesis is that forrard masking is related to neural accommodation (^{Smith 1977 , 1979}). Neural firing decreases, or adapts, during the course of the precursor. If another sound, a signal, follows the precursor, the firing to the bespeak is decreased from what information technology would exist if the signal were preceded by silence (^{Harris and Dallos, 1979}). This subtract in firing might exist expected to increment the threshold for the indicate, i.e., the signal would be masked. An assay of firing rates using signal detection theory predicts much less masking at the level of the auditory nerve than is seen in psychophysical tests (^{Relkin and Turner, 1988}). ^{Meddis and O'Mard (2005)} were able to accommodate an auditory model to predict psychophysical forward masking results from neural adaptation. ^{Oxenham (2001)} too showed that neural adaptation, modeled as a decrease in proceeds, was able to predict many forrard masking results, if compression in the cochlea was also included in the model.

A second theory for forward masking is persistence of excitation. That is, the response to the forerunner persists and overlaps with the response to the signal, making it harder to hear the signal. This is not seen at the level of the auditory nerve, just has been hypothesized to involve a "temporal window" at some college level of the auditory system (^{Moore et al., 1988}). ^{Oxenham (2001)} constitute that if compression in the cochlea was included, the temporal window model was able to predict frontwards masking results.

A third hypothesis is that efferent feedback from the central auditory organization is responsible for some forrard masking. ^{Shore (1998)} observed changes in forrard masking in the ventral cochlear nucleus after lesions to efferent pathways.

The present experiment was developed to examine the hypothesis that forward masking is partially due to efferent feedback, but at the level of the cochlea. There would be a known physiological basis in the medial olivocochlear reflex (MOCR). The MOCR is a decrease in the gain of the agile process of the cochlea, caused by activation of the medial olivocochlear bundle of efferent fibers (^{Warr and Guinan, 1979 ; Warr, 1980 ; Liberman, 1989}). ^{Oxenham (2001)} modeled neural adaptation every bit a subtract in gain, although at a postcochlear level, and the time class of recovery is in the aforementioned range every bit the offset of MOCR effects (^{Backus and Guinan, 2006}). Temporal furnishings in simultaneous masking take been successfully modeled on the basis of a frequency-specific subtract in proceeds in the cochlea, which would be consistent with MOCR activation (^{Strickland 2001 , 2004 , 2008 ; Strickland and Krishnan, 2005}). Although neural adaptation has also been proposed as a basis for the temporal consequence in simultaneous masking, it cannot explicate all aspects of the temporal effect (^{Salary and Healy, 2000}). The temporal window model does not predict the temporal effect in simultaneous masking.

The MOCR hypothesis for frontwards masking would be consistent with a decrease in gain, but at the level of the cochlea. A subtract in the gain of the agile procedure would exist expected to produce effects that would be distinguishable from the effects of a temporal window or of neural accommodation. Specifically, a decrease in the gain of the active procedure should produce a decrease in the gain of the input-output function of the cochlea.

This hypothesis may exist studied using a paradigm called additivity of masking. In this epitome, the masking produced by ii maskers is compared to the masking produced by each masker solitary. Previous inquiry on the effects of two maskers has shown that information technology tin can be assumed that the effects of the maskers add linearly, if cochlear compression is taken into account (e.g., ^{Penner and Shiffrin, 1980 ; Oxenham and Moore, 1994}). The premise of the present study is that there are probably at least two types of forrad masking. Forward masking by brusk maskers seems unlikely to exist due to the efferent feedback to the cochlea. The most rapid MOCR effects autumn in the range of 60–80 ms (^{Backus and Guinan, 2006}). Therefore, a brusk forward masker may be used that should not activate the MOCR. Growth-of-masking (GOM) functions take been used in forwards masking to obtain estimates of the cochlear input-output function (^{Oxenham and Plack, 1997}). A masker approximately an octave beneath the betoken frequency is used to mask a short signal, as a function of indicate level. If the masker response is linear, the thresholds give an guess of the input-output function at the signal frequency place. Thus, a GOM part measured with a short masker and betoken should requite an gauge of proceeds at the betoken frequency identify.

In the remainder of the paper, the longer masker will be referred to as the "precursor." For longer precursor durations, efferent feedback could play a part in forrad masking. Because the MOCR is frequency specific, a long-duration precursor volition be presented at the bespeak frequency, and the GOM function measured. If input-output functions estimated from the two GOM functions show a decrease in gain following a forerunner, this would exist consistent with MOCR activation. The betoken threshold will likewise be measured with the forerunner merely no short forward masker, so that the results may exist analyzed in terms of additivity of masking.

METHODS

Stimuli

The indicate was a vi-ms, four.0-kHz sinusoid, with 3-ms cosine-squared onset and offset ramps (no steady state). This frequency was chosen considering big temporal effects in simultaneous masking have been found for this indicate frequency. The off-frequency masker was a 2.8-kHz tone with a duration of forty ms, including v-ms cosine-squared gating. This masker elapsing was chosen to minimize activation of the MOCR, yet enable thresholds to be measured within the range of the equipment. In that location was no delay between masker offset and signal onset. In the precursor weather, a 4.0-kHz precursor preceded the off-frequency masker with no delay between precursor offset and masker onset. Previous studies using a separate forerunner in simultaneous masking take reported a temporal consequence at the 40-ms forerunner-bespeak delay used in this study (^{Salary and Smith, 1991 ; Bacon and Healy, 2000}).

The effects of forerunner level and duration were examined. The forerunner level was fixed at l or sixty dB SPL, based on pilot data that showed that these levels were effective. The duration was set at 160 ms. This duration was based on previous data in simultaneous masking that showed that the temporal consequence plateaued for a bespeak delay of about 200 ms from masker onset (^{Zwicker, 1965a}). The combined duration of the precursor and masker was 200 ms. The effect of forerunner duration was too examined by using a 40-ms, 60-dB SPL precursor.

Throughout the experiment, high-pass noise was presented to preclude off-frequency listening. The lower cutoff frequency was 1.2f _south , where f _{due south} refers to the signal frequency. The spectrum level of this high-pass racket was set at 40 dB below the signal level. This level was used in a like study (^{Rosengard et al., 2005}). The high-laissez passer noise was turned on 50 ms earlier forerunner onset and turned off fifty ms later the offset of the betoken, to avoid confusion with the other stimuli. Conditions are shown schematically in Fig. ​ 1.

Schematic showing the spectral (y-axis) and temporal (x-axis) characteristics of the (4 kHz,6 ms) signal, (2.8 kHz,40 ms) off-frequency masker, (4 kHz) on-frequency precursor with variable duration and level (bold lines), and high-pass noise (hatched rectangle).

The stimuli were created digitally and were routed through four separate D∕A channels (TDT DA3-4). They were depression pass filtered at 10 kHz (TDT FT5 and FT6-2). The levels of the stimuli were controlled by programmable attenuators (TDT PA-4), mixed (TDT-SM3) and routed to a headphone buffer (TDT HB6) prior to presentation through one of two ER-2A insert earphones to a listener seated in a audio-treated booth. These earphones have a flat frequency response from 250 to 8000 Hz.

Procedures

A three-interval forced choice task with a two-down, one-up stepping rule was used to determine thresholds. Subjects were asked to identify the interval containing the signal by pressing a key on a calculator keyboard. Visual feedback was provided via a computer monitor. Inside each trial, the signal level was fixed and the level of the off-frequency masker varied based on the response. The initial footstep size was five dB, and decreased to two dB after the second reversal. Thresholds were taken as the mean of the terminal even number of reversals at the smaller step size in a fix of 50 trials. This adaptive tracking procedure estimated the 70.7% right bespeak on the psychometric function (^{Levitt, 1971}). The thresholds from at least two runs were averaged to obtain the final threshold. Runs were discarded if the standard deviation exceeded 5 dB or the threshold exceeded the limits of the equipment. Signal thresholds in quiet or following the forerunner alone (with no masker) were as well measured. When no masker was present, the delay between the precursor and signal was nonetheless fixed at twoscore ms. Data were nerveless over several experimental sessions, each lasting i–1.5 hours.

The listener without previous experience in psychoacoustic tasks was trained for 2–3 hours prior to data collection. In a given session, data were nerveless for all precursor conditions at 1 or 2 signal levels.

Subjects

Three subjects participated in this study. All subjects had air conduction thresholds within normal limits (<20 dB HL) and normal middle ear function bilaterally. There were two females and one male, with a median historic period of 28 years. Ii of these subjects had prior experience in psychoacoustic tasks.

RESULTS

GOM functions for the iii listeners are shown in Fig. ​ 2. Filled circles are off-frequency masker thresholds with no precursor. Thresholds are also shown for the off-frequency masker following the l-(open circles) and 60-dB SPL (filled diamonds) 160-ms precursors, and the 60-dB SPL, twoscore-ms forerunner (open squares). The on-frequency forerunner decreased masker thresholds for depression signal levels, simply had little effect at high point levels. This event increased with precursor level. For a 60-dB SPL precursor, there was lilliputian to no effect of decreasing the precursor duration from 160 to 40 ms.

Plots showing the masker level necessary to mask a point, plotted equally a function of signal level without a forerunner (filled circle) and with the three unlike precursors (open circles: 50 dB SPL, 160 ms; filled diamonds: 60 dB SPL, 160 ms; open squares: lx dB SPL, 40 ms). Symbols at bottom left of individual panels indicate signal thresholds obtained for each of the four weather without the off-frequency masker.

Signal thresholds were likewise obtained in the presence of the on-frequency precursor with no off-frequency masker. These are indicated by symbols at the bottom of individual panels. The precursors cause a shift in threshold of approximately 2–15 dB. In a few cases, listeners were able to find a signal that was slightly below quiet threshold, in the presence of the off-frequency masker. For example, for S2, the absolute threshold of the signal solitary was 43 dB SPL (filled circle), just when the off-frequency masker was presented, the point could be detected at 40 dB SPL. This slight improvement in bespeak threshold with a forrard masker has been seen in several subjects, and has been observed previously (^{Zwislocki et al., 1959}).

Input-output functions were estimated for each of the precursor weather condition using the lower two segments of a 3-line office described by ^{Plack et al. (2004)}.

L out = c Fifty in + k 1 + M ( BP 1 < L in ≤ BP 2 ) ,

(2)

where Fifty _in was the level of the signal, L _out was the estimated output for a given signal level, and G, c, and BP_ane were free parameters. The two-line function had a gradient of 1 below the lower breakpoint (BP₁), and a compressive slope (c) between the two BPs. The correction factor thou _one, where yard ₁=BP₁ (1−c), ensured that the 2 lines met at the breakpoint. Equally the GOM data did not show a BP at college signal levels, BP_two was causeless to exist stock-still at 100 dB SPL for all subjects. For some listeners, the presence of the forerunner produced a slope greater than i on the lower leg of the GOM (e.thousand., S3). This has been seen before with a precursor (^{Strickland, 2008}), and may be due to an effect nearly threshold which is not predicted past the model (see ^{Plack and Skeels, 2007}, for a discussion). These points were excluded from the fit. A least-squares minimization procedure was used to judge the free parameters. The parameter estimates from the model are shown in Table ​ 1. The model fit the experimental data very well, with rms errors typically less than 3 dB.

Table 1

Parameters from the two-line fit to the data using a technique derived from ^{Plack et al. (2004)}. G=proceeds, c=slope of compressive office, BP₁=lower breakpoint, BP_two=upper breakpoint. BP₂ was stock-still at 100 dB for all subjects and weather.

Subject area	Precursor level (dB)	Precursor duration (ms)	BP1	c	G	rms mistake
S1	No	⋯	65.54	0.27	23.47	0.98
	50	160	69.84	0.51	19.87	1.40
	60	160	82.22	0.85	17.20	1.19
	lx	xl	70.00	0.74	thirteen.50	ii.82
S2	No	⋯	threescore.39	0.32	26.22	two.22
	fifty	160	63.76	0.44	22.26	1.93
	lx	160	75.51	0.88	sixteen.25	4.76
	60	40	82.84	0.87	14.eighty	2.04
S3	No	⋯	43.67	0.39	27.93	0.98
	50	160	59.05	0.29	15.21	0.59
	60	160	67.61	0.xl	6.39	1.90
	60	xl	67.85	0.20	vii.85	1.27

In examining Tabular array ​ ane, information technology can exist seen that BP₁ increased with the addition of the on-frequency precursor for all subjects. The slope c also increased for S1 and S2. This change increased with forerunner level. Every bit a effect, the maximum gain G decreased with the addition of an on-frequency forerunner. A 10-dB increment in on-frequency precursor level resulted in a decrease in G of approximately 2.five–ix dB. The brusque duration (40 ms) precursor produced the same decrease in gain equally a longer (160 ms) precursor of the same level.

Discussion

Although the results prove a decrease in the gain of input-output functions following a forerunner, it is possible that they could simply reflect additivity of the masking of the on-frequency precursor and the off-frequency masker. This possibility is explored below.

Additivity of masking

Many previous studies have examined the combined furnishings of two temporally nonoverlapping maskers on signal threshold, based on their private furnishings. This has been called additivity of masking. The results in these studies may be explained if it is assumed that the furnishings of the two maskers add together linearly. For instance, suppose in that location are 2 maskers, and each is at the level at which it but masks a 70-dB SPL tone. So when the 2 maskers are presented sequentially, the threshold for the tone should increase to 73 dB SPL, as if the intensity effects of the 2 maskers are added linearly. The threshold for the tone may increment more than than three dB, and this has been attributed to compression.

Estimates for the individual effects for the precursor and masker were obtained by assuming that the GOM measured without a precursor estimated the input-output function at the signal place. The masker effect of the precursor alone was estimated by using the signal threshold in the presence of the forerunner alone (symbols at the lesser of Fig. ​ 2) and using the GOM office to estimate the output level. For example, for S3, the threshold for the signal following a 50-dB SPL precursor was 38 dB SPL (open up circle). On the input-output function, using the role fitted by the equations, this signal would be masked by an off-frequency masker of 66 dB SPL. Thus, this fixed precursor has an effective level of 66 dB SPL. The precursor level was fixed for a given GOM function, so it was assumed that its effective level was constant. The level of the masker varied co-ordinate to the signal level. The effective masker level was taken from the input-output office for each indicate level. For example, for S3, the masker level needed to mask a 50-dB SPL signal was 74 dB SPL. At present, when the forerunner is presented before the masker, what level should the masker be so that the combined issue of the ii together is 74 dB SPL? The masker response is assumed to be linear. Past subtracting the intensities, it tin can be determined that a masker level of 73.3 dB SPL would exist needed. The bodily masker level measured for a 50-dB SPL point following a 50-dB SPL precursor was 65 dB SPL. This level is much lower than would be predicted by additivity of masking.

Figure ​ 3 shows the masker levels predicted past additivity of masking for the fifty- and 60-dB SPL precursors (symbols), forth with the data from Fig. ​ two replotted as lines. For S1 and S2, the predicted results for the two precursors overlie each other for most signal levels, while the actual data do non. Information technology can exist seen that the precursors crusade a larger alter in masker level than is predicted past additivity of masking.

Predictions using an additivity of masking analysis (symbols), along with information from Fig. ​ ii replotted equally lines.

Subtract in gain

Now consider the hypothesis that the gain of the GOM function does subtract following a long-duration forerunner at the indicate frequency. The interpretation would exist that the on-frequency precursor turned down the gain in the cochlea, while the off-frequency masker produced some other type of forward masking. The decrease in gain is graded with precursor level. The decrease in gain observed hither is similar to that reported in a simultaneous masking written report by ^{Strickland (2008)}. She reported a subtract in maximum gain of 4–6 dB for every x dB increase in forerunner level, which is like to the 2.5–9 dB subtract in the present information. That study likewise constitute a decrease in compression with a precursor for some listeners and not others, as in the present report. These data are consistent with ^{Rosengard et al. (2005)}, who found that compression decreased with gain, but not with ^{Plack et al. (2004)}, who plant no correlation between compression and gain. In the present report, S3, who had the most data points on the compressive part of the GOM function, shows the least modify in pinch with a precursor. Thus, the apparent modify in compression may be due to the express number of data points to be fitted for the other listeners.

Data from both simultaneous and forrard masking are consistent with the hypothesis that preceding stimulation decreases the gain of the basilar membrane input-output function. As noted in the Introduction, this would be consistent with the activation of the MOCR. The MOCR hypothesis fits in the context of adaptation of sensory systems in response to the changing environment. Forward masking would then just be a by-product of a organization which is generally beneficial for listening in background dissonance in simultaneous masking.

Comparison to other aspects of temporal effects in simultaneous masking

In this study, the result of the on-frequency precursor was characterized by a decrease in masker level, which may seem contrary to some temporal effects in simultaneous masking, where the masker level increases. The nowadays information are consistent with some conditions in ^{Strickland (2001)}, where the temporal effect was measured in simultaneous masking with a notched-noise masker. Adding a broadband noise precursor before the masker decreased masker levels for wide notch widths. ^{Carlyon (1989)} showed that a narrowband noise forerunner at the signal frequency increased signal threshold. This is similar to the outcome of the on-frequency precursor in our experiment, which decreases the masker level required to mask the indicate. Both the previous simultaneous masking and the current forrad masking results are consistent with a decrease in gain at the signal frequency post-obit a forerunner.

The effectiveness of the short-duration precursor was surprising. In a simultaneous masking report, ^{Bacon and Smith (1991)} showed that a short-duration forerunner was no different from a longer forerunner in its effectiveness, as long equally it was long enough to activate the efferent organization. In this study, information technology was expected that the 40-ms on-frequency forerunner would be too short to activate the efferent system. Still, in add-on to precursor elapsing, information technology appears that the delay between precursor and signal onsets may play a office. For a 160-ms precursor, this delay is 200 ms, whereas for the shorter duration forerunner, it is 80 ms. The time grade of onset of the MOCR is on boilerplate about seventy ms (^{Backus and Guinan, 2006 ; Guinan, 2006}). It is, therefore, possible that the 40-ms on-frequency forerunner could take activated the MOCR.

Another interesting aspect of this study is the fact that a temporal effect is seen when the preceding stimulation is just at the indicate frequency. Past studies have typically shown that in order to produce a temporal consequence, the forerunner and∕or simultaneous masker must contain energy above the signal frequency (^{Zwicker, 1965b ; McFadden, 1989 ; Bacon and Smith, 1991}). 1 reason that this might be true is that it would eliminate the possibility of off-frequency listening. If listeners are able to attend to filters to a higher place the indicate frequency, where the growth of excitation to the betoken is more linear, a temporal effect might not be seen. Another reason could be that the temporal result depends on suppression. The results of the nowadays study are consistent with the off-frequency listening hypothesis. High-pass noise presented with the point eliminated the possibility of off-frequency listening. This is consistent with temporal effects seen with tonal stimuli at loftier frequencies, where off-frequency listening would also not be effective due to the sharp increase in thresholds above the signal frequency (^{Schmidt and Zwicker, 1991 ; Carlyon and White, 1992}). Thus, this shows that a temporal effect tin exist seen in a status in which suppression is not playing a role. This is not to advise that suppression never plays a role in the temporal effect, only that it is non a necessary status.

ACKNOWLEDGMENTS

We give thanks Skyler Jennings for his valuable comments on the manuscript. This research was supported in role by funds from the Speech, Language, and Hearing Sciences Department at Purdue University and Grant No. R01-DC008327 from the National Establish on Deafness and Other Communication Disorders (NIDCD) of the National Institutes of Wellness (NIH).

Notes

¹Portions of this inquiry were presented at the 30th Midwinter Coming together of the Association for Enquiry in Otolaryngology, Denver, CO, February 2007.

References

• Backus, B. C., and Guinan, Jr., J. J. (2006). "Fourth dimension-form of the homo medial olivocochlear reflex," J. Acoust. Soc. Am. 10.1121/1.2169918 119, 2889–2904. [PubMed] [CrossRef] [Google Scholar]
• Bacon, Southward. P., and Healy, Eastward. W. (2000). "Furnishings of ipsilateral and contralateral precursors on the temporal effect in simultaneous masking with pure tones," J. Acoust. Soc. Am. ten.1121/1.428443 107, 1589–1597. [PubMed] [CrossRef] [Google Scholar]
• Bacon, Due south. P., and Smith, Yard. A. (1991). "Spectral, intensive, and temporal factors influencing overshoot," Q. J. Exp. Psychol. A 43, 373–399. [PubMed] [Google Scholar]
• Carlyon, R. P. (1989). "Changes in the masked thresholds of brief tones produced by prior bursts of dissonance," Hear. Res. x.1016/0378-5955(89)90014-2 41, 223–235. [PubMed] [CrossRef] [Google Scholar]
• Carlyon, R. P. and White, L. J. (1992). "Result of betoken frequency and masker level on the frequency regions responsible for the overshoot outcome," J. Acoust. Soc. Am. 10.1121/1.402629 91, 1034–1041. [PubMed] [CrossRef] [Google Scholar]
• Guinan, Jr., J. J. (2006). "Olivocochlear efferents: Anatomy, physiology, function, and the measurement of efferent furnishings in humans," Ear Hear. 10.1097/01.aud.0000240507.83072.e7 27, 589–607. [PubMed] [CrossRef] [Google Scholar]
• Harris, D. G., and Dallos, P. (1979). "Forward masking of auditory nerve cobweb responses," J. Neurophysiol. 42, 1083–1107. [PubMed] [Google Scholar]
• Hicks, 1000. L., and Bacon, South. P. (1992). "Factors influencing temporal effects with notched-racket maskers," Hear. Res. ten.1016/0378-5955(92)90174-L 64, 123–132. [PubMed] [CrossRef] [Google Scholar]
• Levitt, H. (1971). "Transformed up-down methods in psychoacoustics," J. Acoust. Soc. Am. x.1121/1.1912375 49, 467–477. [PubMed] [CrossRef] [Google Scholar]
• Liberman, M. C. (1989). "Rapid assessment of sound-evoked olivocochlear feedback: Suppression of chemical compound action potentials by contralateral audio," Hear. Res. 10.1016/0378-5955(89)90127-5 38, 47–56. [PubMed] [CrossRef] [Google Scholar]
• McFadden, D. (1989). "Spectral differences in the power of temporal gaps to reset the mechanisms underlying overshoot," J. Acoust. Soc. Am. 10.1121/1.397732 85, 254–261. [PubMed] [CrossRef] [Google Scholar]
• Meddis, R., and O'Mard, L. P. (2005). "A computer model of the auditory-nerve response to forrad-masking stimuli," J. Acoust. Soc. Am. 10.1121/1.1893426 117, 3787–3798. [PubMed] [CrossRef] [Google Scholar]
• Moore, B. C. J., Glasberg, B. R., Plack, C. J., and Biswas, A. K. (1988). "The shape of the ear's temporal window," J. Acoust. Soc. Am. 10.1121/1.396055 83, 1102–1116. [PubMed] [CrossRef] [Google Scholar]
• Oxenham, A. J. (2001). "Frontward Masking: Adaptation or integration?" J. Acoust. Soc. Am. 10.1121/ane.1336501 109, 732–741. [PubMed] [CrossRef] [Google Scholar]
• Oxenham, A. J., and Moore, B. C. J. (1994). "Modeling the additivity of nonsimultaneous masking," Hear. Res. ten.1016/0378-5955(94)90014-0 lxxx, 105–118. [PubMed] [CrossRef] [Google Scholar]
• Oxenham, A. J., and Plack, C. J. (1997). "A behavioral measure of basilar-membrane non-linearity in listeners with normal and impaired hearing," J. Acoust. Soc. Am. 10.1121/i.418327 101, 3666–3675. [PubMed] [CrossRef] [Google Scholar]
• Penner, Chiliad. J., and Shiffrin, R. K. (1980). "Nonlinearities in the coding of intensity within the context of a temporal summation model," J. Acoust. Soc. Am. 10.1121/1.383885 67, 617–627. [PubMed] [CrossRef] [Google Scholar]
• Plack, C. J., Drga, V., and Lopez-Poveda, Eastward. A. (2004). "Inferred basilar-membrane response functions for listeners with mild to moderate sensorineural hearing loss," J. Acoust. Soc. Am. 10.1121/1.1675812 115, 1684–1695. [PubMed] [CrossRef] [Google Scholar]
• Plack, C. J., and Skeels, V. (2007). "Temporal integration and compression near absolute threshold in normal and impaired ears," J. Acoust. Soc. Am. ten.1121/1.2769829 122, 2236–2244. [PubMed] [CrossRef] [Google Scholar]
• Relkin, E. M., and Turner, C. Due west. (1988). "A reexamination of forward masking in the auditory nerve," J. Acoust. Soc. Am. x.1121/1.396836 84, 584–591. [PubMed] [CrossRef] [Google Scholar]
• Rosengard, P. Due south., Oxenham, A. J., and Braida, 50. D. (2005). "Comparing different estimates of cochlear pinch in listeners with normal and impaired hearing," J. Acoust. Soc. Am. 10.1121/1.1883367 117, 3028–3041. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
• Schmidt, S., and Zwicker, E. (1991). "The effect of masker spectral disproportion on overshoot in simultaneous masking." J. Acoust. Soc. Am. ten.1121/1.400656 89, 1324–1330. [PubMed] [CrossRef] [Google Scholar]
• Shore, S. E. (1998). "Influence of centrifugal pathways on forward masking of ventral cochlear nucleus neurons," J. Acoust. Soc. Am. 10.1121/1.423294 104, 378–389. [PubMed] [CrossRef] [Google Scholar]
• Smith, R. L. (1977). "Short-term accommodation in single auditory nervus fibers: Some poststimulatory furnishings," J. Neurophysiol. 40, 1098–1112. [PubMed] [Google Scholar]
• Smith, R. 50. (1979). "Accommodation, saturation, and physiological masking in unmarried auditory-nerve fibers," J. Acoust. Soc. Am. ten.1121/1.382260 65, 166–178. [PubMed] [CrossRef] [Google Scholar]
• Strickland, E. A. (2001). "The human relationship betwixt frequency selectivity and overshoot," J. Acoust. Soc. Am. x.1121/i.1357811 109, 2063–2073. [CrossRef] [Google Scholar]
• Strickland, E. A. (2004). "The temporal effect with notched-noise maskers: Analysis interms of input-output functions," J. Acoust. Soc. Am. x.1121/1.1691036 115, 2234–2245. [PubMed] [CrossRef] [Google Scholar]
• Strickland, E. A. (2008). "The relationship between precursor level and the temporal effect," J. Acoust. Soc. Am. 10.1121/1.2821977 123, 946–954. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
• Strickland, Due east. A., and Krishnan, L. A. (2005). "The temporal result in listeners with mild to moderate cochlear hearing impairment," J. Acoust. Soc. Am. x.1121/1.2074787 118, 3211–3217. [PubMed] [CrossRef] [Google Scholar]
• Warr, W. B. (1980). "Efferent components of the auditory system," Ann. Otol. Rhinol. Laryngol. 90, 114–190. [Google Scholar]
• Warr, W. B., and Guinan, Jr., J. J. (1979). "Efferent innervation of the organ of Corti: 2 carve up systems," Brain Res. 10.1016/0006-8993(79)91104-1 173, 152–155. [PubMed] [CrossRef] [Google Scholar]
• Zwicker, E. (1965a). "Temporal effects in simultaneous masking by white-dissonance bursts," J. Acoust. Soc. Am. ten.1121/1.1909389 37, 653–666. [CrossRef] [Google Scholar]
• Zwicker, E. (1965b). "Temporal effects in simultaneous masking and loudness," J. Acoust. Soc. Am. 10.1121/ane.1909588 38, 132–141. [PubMed] [CrossRef] [Google Scholar]
• Zwislocki, J., Pirodda, E., and Rubin, H. (1959). "On some poststimulatory effects at the threshold of audibility," J. Acoust. Soc. Am. 10.1121/i.1907619 31, 9–14. [CrossRef] [Google Scholar]

---

Articles from The Journal of the Acoustical Society of America are provided here courtesy of Acoustical Club of America

---

hayesandereliked.blogspot.com

Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2637535/

Share this post