Does silence play a peripheral role in the perception of stops?

Abstract

A number of recent studies have investigated the role played by silence in the perception of speech stimuli, demonstrating that the perception of a subsequent stop is dependent upon the duration of the silent interval. If silence is acting simply to separate the stop from relatively peripheral interference arising from the pre-silence components of the stimulus, then we would expect that a separation of the same stimulus components by differential lateralization would, in a similar fashion, improve the perception of the stop consonant; in effect, lateralization would be traded for silence. We investigated this prediction using an /s-day/ natural speech continua. By selectively inverting the stimulus tokens, we created binaurual stimuli which were interaurally phase shifted by either 0 or π rad. The temporal boundary for the perception of /stay/ was equivalent for all four combinations of the binaural /s/ and /day/ tokens. These results, and the results with other natural speech tokens, will be discussed in terms of their implications concerning the role of peripheral versus central interactions among stimulus components. [Work supported by NSF Grant BNS 8003704.]