Detection thresholds for 100 ms of either 5- or 20-Hz frequency modulation (FM) were measured at various temporal positions within a 600-ms, 4-kHz pure-tone carrier. The results indicated that the temporal position of the signal relative to the fringe influences detection thresholds, including an effect that is reminiscent of auditory backward recognition masking. A task involving frequency increments, rather than sinusoidal FM, yielded similar results. Additional manipulation of total carrier duration indicated that FM detection thresholds improve as the duration of the forward fringe increases, while a backward fringe only degrades performance in the absence of any forward fringe. The results suggest that listeners are insensitive to subtle frequency changes that occur at the onset of a longer stimulus and that the interaction between the opposing effects of the forward and backward fringes is not additive.
Bibliographical noteFunding Information:
The authors would like to thank Dr. Brian C. J. Moore and an anonymous reviewer who provided helpful comments and suggestions for improving this manuscript. This work was supported by Research Grant No. R01 DC 00683 from the National Institute on Deafness and Communication Disorders, National Institutes of Health.
Copyright 2013 Elsevier B.V., All rights reserved.