No spatial release from amplitude modulation masking

Authors

  • Eric R. Thompson Centre for Applied Hearing Research, Technical University of Denmark, DK-2800 Lyngby, Denmark; Hearing Research Center, Boston University, Boston, MA 02215, USA
  • Torsten Dau Centre for Applied Hearing Research, Technical University of Denmark, DK-2800 Lyngby, Denmark
  • Barbara G. Shinn-Cunningham Hearing Research Center, Boston University, Boston, MA 02215, USA

Abstract

In many signal detection and speech intelligibility studies, performance is improved if there is a perceived spatial separation between the target and the masker, as compared to when the target and masker are perceived to be co-located. The goal of the present study was to determine if a similar spatial release from masking can be measured in a masked amplitude modulation (AM) detection experiment. Temporally interleaved transposed stimuli were used as AM carriers for the experiments. These carriers could be lateralized separately using only interaural time differences (ITDs) and not interaural level differences (ILDs). The rst experiment measured the perceived lateral positions of the probe and masker, independently and in combination. Experiment two used the same stimuli as carriers for measuring masked modulation detection thresholds. The results showed that the probe and masker could be perceived to come from separate lateral positions. The modulation detection results showed bandpass modulation-frequency tuning. There was no improvement in modulation thresholds when the target was diotic and the masker was lateralized with a 1-ms ITD, as compared to the co-located condition.

References

Bacon, S. P., and Grantham, D. W. (1989). “Modulation masking: Effects of modulation frequency, depth, and phase,” J. Acoust. Soc. Am. 85, 2575-2580.

Bacon, S. P., and Opie, J. M. (1994). “Monotic and dichotic modulation detection interference in practiced and unpracticed subjects,” J. Acoust. Soc. Am. 95, 2637- 2641.

Bernstein, L. R., and Trahiotis, C. (2003). “Enhancing interaural-delay-based extents of laterality at high frequencies by using ‘transposed stimuli’,” J. Acoust. Soc. Am. 113, 3335-3347.

Buell, T. N., Trahiotis, C., and Bernstein, L. R. (1991). “Lateralization of low- frequency tones: Relative potency of gating and ongoing interaural delays,” J. Acoust. Soc. Am. 90, 3077-3085.

Carlile, S., Hyams, S., and Delaney, S. (2001). “Systematic distortions of auditory space percep-tion following prolonged exposure to broadband noise,” J. Acoust. Soc. Am. 110, 416-424.

Dreyer, A., and Delgutte, B. (2006). “Phase locking of auditory-nerve bers to the envelopes of high-frequency sounds: Implications for sound localization,” J. Neurophysiol. 96, 2327-2341.

van der Heijden, M., and Trahiotis, C. (1999). “Masking with interaurally delayed stimuli: The use of ‘internal’ delays in binaural detection,” J. Acoust. Soc. Am. 105, 388-399.

Heller, L. M., and Trahiotis, C. (1996). “Extents of laterality and binaural interference effects,” J. Acoust. Soc. Am. 99, 3632-3637.

Houtgast, T. (1989). “Frequency selectivity in amplitude-modulation detection,” J. Acoust. Soc. Am. 85, 1676-1680.

Kopčo, N., and Shinn-Cunningham, B. G. (2008). “In uences of modulation and spatial separation on detection of a masked broadband target,” J. Acoust. Soc. Am. 124, 2236-2250.

Levitt, H. (1971). “Transformed up-down methods in psychoacoustics,” J. Acoust. Soc. Am. 49, 467-477.

van de Par, S., and Kohlrausch, A. (1997). “A new approach to comparing binaural masking level differences at low and high frequencies,” J. Acoust. Soc. Am. 101, 1671-1680.

Sheft, S., and Yost, W. A. (1997). “Binaural modulation detection interference,” J. Acoust. Soc. Am. 102, 1791-1798.

Additional Files

Published

2009-12-15

How to Cite

Thompson, E. R., Dau, T., & Shinn-Cunningham, B. G. (2009). No spatial release from amplitude modulation masking. Proceedings of the International Symposium on Auditory and Audiological Research, 2, 191–202. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2009-20

Issue

Section

2009/2. Perceptual measures and models of spatial hearing