title: The role of compression in the simultaneous masker phase effect.
abstract: Peripheral compression is believed to play a major role in the masker phase effect (MPE). While compression is almost instantaneous, activation of the efferent system reduces compression in a temporally evolving manner. To study the role of efferent-controlled compression in the MPE, in experiment 1, simultaneous masking of a 30-ms 4-kHz tone by 40-ms Schroeder-phase harmonic complexes was measured with on- and off-frequency precursors as a function of masker phase curvature for two masker levels (60 and 90 dB sound pressure level). The MPE was quantified by the threshold range [min/max difference (MMD)] across the phase curvatures. For the 60-dB condition, the presence of on-frequency precursor decreased the MMD from 10 to 5 dB. Experiment 2 studied the role of the precursor on the auditory filter's bandwidth. The on-frequency precursor was found to increase the bandwidth, an effect incorporated in the subsequent modeling. A model of the auditory periphery including cochlear filtering and basilar membrane compression generally underestimated the MMDs. A model based on two-step compression, including compression of inner hair cells, accounted for the MMDs across precursor and level conditions. Overall, the observed precursor effects and the model predictions suggest an important role of compression in the simultaneous MPE.
authors: Austrian Academy of Sciences, Acoustics Research Institute, Wohllebengasse 12-14, 1040 Vienna, Austria.
authors: Hisaaki
authors: H
authors: Tabuchi
authors: Austrian Academy of Sciences, Acoustics Research Institute, Wohllebengasse 12-14, 1040 Vienna, Austria.
authors: Bernhard
authors: B
authors: Laback
authors: Austrian Academy of Sciences, Acoustics Research Institute, Wohllebengasse 12-14, 1040 Vienna, Austria.
authors: Thibaud
authors: T
authors: Necciari
authors: Austrian Academy of Sciences, Acoustics Research Institute, Wohllebengasse 12-14, 1040 Vienna, Austria.
authors: Piotr
authors: P
authors: Majdak