The effect of the preceding masking noise on monaural and binaural release from masking

When a target tone is preceded by a noise, the threshold for target detection can be increased or decreased depending on the type of a preceding masker. The effect of preceding masker to the following sound can be interpreted as either the result of adaptation at the periphery or at the system level. To disentangle these, we investigated the time constant of adaptation by varying the length of the preceding masker. For inducing various masking conditions, we designed stimuli that can induce masking release. Comodulated masking noise and binaural cues can facilitate detecting a target sound from noise. These cues induce a decrease in detection thresholds, quantified as comodulation masking release (CMR) and binaural masking level difference (BMLD), respectively. We hypothesized that if the adaptation results from the top-down processing, both CMR and BMLD will be affected with increased length of the preceding masker. We measured CMR and BMLD when the length of preceding maskers varied from 0 (no preceding masker) to 500 ms. Results showed that CMR was more affected with longer preceding masker from 100 ms to 500 ms while the preceding masker did not affect BMLD. In this study, we suggest that the adaptation to preceding masking sound may arise from low level (e.g. cochlear nucleus, CN) rather than the temporal integration by the higher-level processing.

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Ecological validity of masking release with speech-like stimuli

10.1101/2021.11.07.467581 ◽

2021 ◽

Author(s):

Hyojin Kim ◽

Viktorija Ratkute ◽

Bastian Epp

Keyword(s):

Speech Perception ◽

Temporal Dynamics ◽

Ecological Validity ◽

Detection Thresholds ◽

Formant Frequencies ◽

Masking Release ◽

Grouping Effect ◽

Masking Level Difference ◽

Masking Noise ◽

Comodulation Masking Release

Comodulated masking noise and binaural cues can facilitate detecting a target sound from noise. These cues can induce a decrease in detection thresholds, quantified as comodulation masking release (CMR) and binaural masking level difference (BMLD), respectively. However, their relevance to speech perception is unclear as most studies have used artificial stimuli different from speech. Here, we investigated their ecological validity using sounds with speech-like spectro-temporal dynamics. We evaluated the ecological validity of such grouping effect with stimuli reflecting formant changes in speech. We set three masker bands at formant frequencies F1, F2, and F3 based on CV combination: /gu/, /fu/, and /pu/. We found that the CMR was little (< 3 dB) while BMLD was comparable to previous findings (~ 9 dB). In conclusion, we suggest that other features may play a role in facilitating frequency grouping by comodulation such as the spectral proximity and the number of masker bands.

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Comodulation masking release and the masking-level difference

The Journal of the Acoustical Society of America ◽

10.1121/1.400739 ◽

1991 ◽

Vol 89 (6) ◽

pp. 3007-3008 ◽

Cited By ~ 8

Author(s):

Marion F. Cohen ◽

Earl D. Schubert

Keyword(s):

Level Difference ◽

Masking Release ◽

Masking Level Difference ◽

Comodulation Masking Release

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Tone detection thresholds in interaurally delayed noise of different bandwidths

Acta Acustica ◽

10.1051/aacus/2021054 ◽

2021 ◽

Vol 5 ◽

pp. 60

Author(s):

Mathias Dietz ◽

Jörg Encke ◽

Kristin I Bracklo ◽

Stephan D Ewert

Keyword(s):

Temporal Coherence ◽

Delay Lines ◽

Detection Thresholds ◽

Filter Bandwidth ◽

Masking Release ◽

Interaural Phase ◽

Significant Difference ◽

Masking Noise ◽

Interaural Phase Difference ◽

Interaural Time Delay

Differences between the interaural phase of a noise and a target tone improve detection thresholds. The maximum masking release is obtained for detecting an antiphasic tone (Sπ) in diotic noise (N0). It has been shown in several studies that this beneﬁt gradually declines as an interaural time delay (ITD) is applied to the noise. This decline has been attributed to the reduced interaural coherence of the noise. Here, we report detection thresholds for a 500 Hz tone in masking noise with ITDs up to 8 ms and bandwidths from 25 to 1000 Hz. Reducing the noise bandwidth from 100 to 50 and 25 Hz increased the masking release for 8-ms ITD, as expected for increasing temporal coherence with decreasing bandwidth. For bandwidths of 100–1000 Hz no significant difference in masking release was observed. Detection thresholds with these wider-band noises had an ITD dependence that is fully described by the temporal coherence imposed by the typical monaurally determined auditory-filter bandwidth. A binaural model based on interaural phase-difference fluctuations accounts for the data without using delay lines.

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Masking release for gap detection

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1992.0066 ◽

1992 ◽

Vol 336 (1278) ◽

pp. 331-337 ◽

Cited By ~ 5

Keyword(s):

Random Noise ◽

Detection Threshold ◽

Signal Frequency ◽

Frequency Noise ◽

Gap Detection ◽

Noise Masking ◽

Level Difference ◽

Masking Release ◽

Masking Level Difference ◽

Release From Masking

In random noise, masking is influenced almost entirely by noise components in a narrow band around the signal frequency. However, when the noise is not random, but has a modulation pattern which is coherent across frequency, noise components relatively remote from the signal frequency can actually produce a release from masking. This masking release has been called comodulation masking release (CMR). The present research investigated whether a similar release from masking occurs in the analysis of a suprathreshold signal. Specifically, the ability to detect the presence of a temporal gap was investigated in conditions which do and do not result in CMR for detection threshold. Similar conditions were investigated for the masking level difference (a binaural masking release phenomenon). The results indicated that suprathreshold masking release for gap detection occurred for both the masking-level difference (MLD) and for CMR. However, masking release for gap detection was generally smaller than that obtained for detection threshold. The largest gap detection masking release effects obtained corresponded to relatively low levels of stimulation, where gap detection was relatively poor.

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Frequency Selectivity and Comodulation Masking Release in Adults and in 6-Year-Old Children

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.3301.96 ◽

1990 ◽

Vol 33 (1) ◽

pp. 96-102 ◽

Cited By ~ 31

Author(s):

Kathleen Veloso ◽

Joseph W. Hall ◽

John H. Grose

Keyword(s):

Frequency Selectivity ◽

Center Frequency ◽

Signal Frequency ◽

Noise Masking ◽

Masking Release ◽

Noise Masker ◽

Wideband Noise ◽

Masking Noise ◽

Comodulation Masking Release ◽

Narrowband Noise

Frequency selectivity and comodulation masking release (CMR) for a 1000-Hz signal frequency were examined in 6-year-old children and adults. An abbreviated measure of frequency selectivity was also conducted for a 500-Hz signal. Frequency selectivity was measured using a notched-noise masking method, and CMR was measured using narrow bands of noise whose amplitude envelopes were either uncorrelated or correlated. There were 6 listeners in each age group. No differences were observed between the adults and children for either auditory measure. Similarly, no differences were observed in the ability to detect a pure-tone signal in a relatively wideband noise masker. When the masking noise was narrowband, however, the masked thresholds of the children were higher than those of the adults. Two characteristics that distinguish narrowband noise from wideband noise are: (1) narrowband noise has a pitch quality corresponding to its center frequency, whereas wideband noise does not have a definite pitch; (2) the intensity fluctuations are relatively greater in narrowband noise than in wideband noise. This may suggest that 6-year-old children have a reduced ability to detect signals in noise backgrounds where the signal has perceptual qualities similar to the noise, or in noise backgrounds having a high degree of fluctuation.

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