Bruce A. Schneider
Dept. of Psychol., Erindale Campus, Univ. of Toronto, Mississauga, ON L5L 1C6, Canada
Margaret Kathleen Pichora-Fuller
Univ. of British Columbia, Vancouver, BC V6T 1Z3, Canada
Threshold for detecting a gap between two Gaussian-modulated, 2-kHz tones ((sigma)=0.5 ms) were determined in young and old listeners. The gap detection thresholds of old subjects were more variable and about twice as large as those obtained from young subjects. Moreover, gap detection thresholds were not correlated with audiometric thresholds in either group. Estimates of the width of the temporal window of young subjects, based on the detection of a gap between two tone pips, were smaller than those typically obtained when a relatively long duration pure tone is interrupted [Moore et al., J. Acoust. Soc. Am. 85, 1266--1275 (1989)]. Because the amount of time it takes to recover from an adapting stimulus is likely to affect gap detection thresholds, smaller estimates of temporal window size would be expected in this paradigm if the amount of adaptation produced by the first tone pip was negligible. The larger gap detection thresholds of old subjects indicates that they may have larger temporal windows than young subjects.