Mechanisms of within- and across-channel processing in comodulation masking release

Authors

  • Tobias Piechowiak Centre for Applied Hearing Research, Ørsted•DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark
  • Stephan D. Ewert Carl von Ossietsky Universität Oldenburg, Medizinische Physik D-26111 Oldenburg, Germany
  • Torsten Dau Centre for Applied Hearing Research, Ørsted•DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark

Abstract

The audibility of a target sound embedded in another masking sound can be improved by adding sound energy that is remote in frequency from both the masker and the target. This effect is known as comodulation masking release (CMR) and is observed when the remote sound and the masker share coherent patterns of amplitude modulation. Most ecologically relevant sounds, such as speech and animal vocalizations, have coherent amplitude modulation patterns across different frequency regions, suggesting that the detection and recognition advantages conveyed by such coherent modulations may play a fundamental role in our ability to deal with natural complex acoustic environments. While a large body of data has been presented, the mechanisms underlying CMR are not clear. This study proposes an auditory processing model that accounts for various aspects of CMR. The model includes an equalization-cancellation (EC) stage for the processing of stimulus information across the audio-frequency axis. The EC process, which is conceptually similar to the across-ear processing in binaural models, is assumed in the model to take place at the output of a modulation filterbank stage for each audio-frequency channel. This approach has been proven successful in several basic conditions of CMR (Piechowiak et al., 2007). In the present study, a modified version of the model is tested that includes a non-linear cochlear ltering stage, the dual resonance nonlinear lterbank (DRNL). It is investigated to what extent the within and across-frequency processes contributing to CMR depend on cochlear non- linear processing.

References

Carlyon, R., and Stubbs, R. (1989). “Detecting single-cycle frequency modulation imposed on sinusoidal, harmonic, and inharmonic carriers,” J. Acoust. Soc. Am. 85, 2563–2574.

Dau, T., Kollmeier B., and Kohlrausch, A. (1997a). “Modeling auditory processing of amplitude modulation. I. Detection and masking with narrow-band carriers,” J. Acoust. Soc. Am. 102, 2893–2905.

Dau, T., Kollmeier, B., and Kohlrausch, A. (1997b). “Modeling auditory processing of amplitude modulation. II. Spectral and temporal integration,” J. Acoust. Soc. Am. 102, 2906–2919

Durlach, N. I. (1963). “Equalization and cancellation theory of binaural masking-level differences,” J. Acoust. Soc. Am. 35, 1206–1218.

Haggard, M. P., Hall, J. W., and Grose, J. H. (1990). “Comodulation masking release as a function of bandwidth and test frequency,” J. Acoust. Soc. Am. 88, 113–118.

Hall, J. W., Haggard, M. P., and Fernandes, M. A. (1984a). “Detection in noise by spectrotemporal pattern analysis,” J. Acoust. Soc. Am. 76, 50–56.

Hall, J. W., and Grose, J. H. (1990). “Comodulation masking release and auditory grouping,” J. Acoust. Soc. Am. 88, 119–125.

Meddis, R., O’Mard, L. P., and Lopez-Poveda, E. A. (2001). “A computational algorithm for computing nonlinear auditory frequency selectivity,” J. Acoust. Soc. Am. 109, 2852–2861.

Schooneveldt, G. P., and Moore, B. C. (1987). “Comodulation masking release (CMR): effects of signal frequency, anking-band frequency, masker bandwidth, anking-band level, and monotic versus dichotic presentation of the anking band,” J. Acoust. Soc. Am. 82, 1944–1956.

Schooneveldt, G. P., and Moore, B. C. (1989). “Comodulation masking release (CMR) as a function of masker bandwidth, modulator bandwidth and signal duration”, J. Acoust. Soc. Am. 85, 273-281.

Verhey, J., Dau, T., and Kollmeier, B. (1999). “Within-channel cues in comodulation masking release (CMR): Experiments and model predictions using a modulation-filterbank model,” J. Acoust. Soc. Am. 106, 2733–2745.

Additional Files

Published

2007-12-15

How to Cite

Piechowiak, T., Ewert, S. D., & Dau, T. (2007). Mechanisms of within- and across-channel processing in comodulation masking release. Proceedings of the International Symposium on Auditory and Audiological Research, 1, 103–112. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2007-10

Issue

Vol. 1 (2007): Auditory Signal Processing in Hearing Impaired Listeners

Section

2007/1. Auditory signal processing and perception

License

Authors who publish with this journal agree to the following terms:

a. Authors retain copyright* and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.

b. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.

c. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).

*From the 2017 issue onward. The Danavox Jubilee Foundation owns the copyright of all articles published in the 1969-2015 issues. However, authors are still allowed to share the work with an acknowledgement of the work's authorship and initial publication in this journal.