, Volume 67, Issue 6, pp 1088-1101

The relation between auditory temporal interval processing and sequential stream segregation examined with stimulus laterality differences

Abstract

In this study, we examine the effects of laterality differences between noise bursts on two objective measures of temporal interval processing (gap detection and temporal asymmetry detection) and one subjective measure of temporal organization (stream segregation). Noise bursts were lateralized by presentation to different ears or dichotic presentation with oppositely signed interaural level (ILD) or time (ITD) differences. Objective thresholds were strongly affected by ear-of-entry differences, were moderately affected by ILD differences, but were unaffected by ITD differences. Subjectively, A and B streams segregated well on the basis of ear-of-entry or ILD differences but segregated poorly on the basis of ITD differences. These results suggest that perceptual segregation may be driven more effectively by differential activation of the two ears (peripheral channeling) than by differences in perceived laterality.

This research was supported by a Natural Sciences and Engineering Research Council (NSERC) grant to D.P.P., and by NSERC and I. W. Killam doctoral fellowships to S.E.B. It is based on part of the doctoral dissertation of S.E.B., parts of which have been previously published in abstract form.