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. 2010 Sep;128(3):1272-9.
doi: 10.1121/1.3463808.

Shifting fundamental frequency in simulated electric-acoustic listening

Christopher A Brown  1 , Nicole M Scherrer, Sid P Bacon
Affiliations

Shifting fundamental frequency in simulated electric-acoustic listening

Christopher A Brown et al. J Acoust Soc Am. 2010 Sep.

Abstract

Previous experiments have shown significant improvement in speech intelligibility under both simulated [Brown, C. A., and Bacon, S. P. (2009a). J. Acoust. Soc. Am. 125, 1658-1665; Brown, C. A., and Bacon, S. P. (2010). Hear. Res. 266, 52-59] and real [Brown, C. A., and Bacon, S. P. (2009b). Ear Hear. 30, 489-493] electric-acoustic stimulation when the target speech in the low-frequency region was replaced with a tone modulated in frequency to track the changes in the target talker's fundamental frequency (F0), and in amplitude with the amplitude envelope of the target speech. The present study examined the effects in simulation of applying these cues to a tone lower in frequency than the mean F0 of the target talker. Results showed that shifting the frequency of the tonal carrier downward by as much as 75 Hz had no negative impact on the benefit to intelligibility due to the tone, and that even a shift of 100 Hz resulted in a significant benefit over simulated electric-only stimulation when the sensation level of the tone was comparable to that of the tones shifted by lesser amounts.

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Figures

Figure 1
Figure 1
Mean percent correct scores for experiment 1. Panel A represents performance when the low-frequency tone was modulated in frequency with the dynamic changes in the target talker's F0. Panel B represents performance when the tone was also modulated with the amplitude envelope of the low-pass target speech. The frequency of the tonal carrier is along the x axis, and percent correct is along the y axis. Each plot represents a different background.
Figure 2
Figure 2
Mean percent correct scores for the follow-up pilot experiment to experiment 1. The frequency of the tonal carrier is along the x axis, and percent correct is along the y axis. The x axis is identical to that of Fig. 1, with the addition of the 84 adjusted data point (84eq), which represents performance when the level of the carrier tone was adjusted to be equal in sensation level (SL) to that of the 184-Hz tone. The background was multi-talker babble.
Figure 3
Figure 3
Mean percent correct scores as a function of the level of the low-frequency tone, in dB SL. Each plot represents performance at a different tonal carrier frequency. The background was multi-talker babble.
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References

    1. ANSI (1996). American National Standards Specifications for Audiometers (ANSI, New York).
    1. Assmann, P. F. (1999). “Fundamental frequency and the intelligibility of competing voices,” in Proceedings of the 14th International Congress of Phonetic Science, pp. 179–182.
    1. Assmann, P. F., and Summerfield, Q. (1990). “Modeling the perception of concurrent vowels: vowels with different fundamental frequencies,” J. Acoust. Soc. Am. JASMAN 88, 680–697.10.1121/1.399772 - DOI - PubMed
    1. Auditec (1997). “Auditory tests (revised),” Compact Disc, Auditec, St. Louis, MO.
    1. Bird, J., and Darwin, C. J. (1997). “Effects of a difference in fundamental frequency in separating two sentences,” in paper for the 11th International Conference on Hearing, Grantham, UK, August.

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