ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

2pPP12. Frequency discrimination in noise by untrained listeners.

Dept. Speech & Hear. Sci., JG-15, Univ. of Washington, Seattle, WA 98195

The frequency discrimination performance of adults, with no prior experience as listeners in psychoacoustic experiments, was examined for tones of 1000 and 4000 Hz presented in a background of broadband noise. The tones were presented at a signal-to-noise ratio expected to produce 80% correct detection. The level of the stimuli was either 45 or 60 dB SPL. The subjects were tested in a procedure similar to one used in infant psychoacoustics [Olsho et al., Devel. Psychol. 23, 627--640 (1987)]. Threshold values of (Delta)f were found to be more similar to those of well-trained listeners at 4000 Hz than at 1000 Hz. The effects of stimulus level were similar to those reported by Dye and Hafter [ 1748--53 (1980)] for well-trained listeners: Threshold (Delta)f increased with increasing level at 4000 Hz, but not at 1000 Hz. This result suggests that the effects of level on frequency discrimination in noise are robust enough to be replicated in subjects with little listening experience. Further, the effects of level on human infants' frequency discrimination in noise may provide important information about why their frequency discrimination in quiet is more adultlike at high frequencies. [Work supported by NIDCD DC00396.]