I Scream for Ice Cream: Resolving Lexical Ambiguity with Sub-phonemic Information

Abstract

This study uses a response mouse-tracking paradigm to examine the role of sub-phonemic information in online lexical ambiguity resolution of continuous speech. We examine listeners’ sensitivity to the sub-phonemic information that is specific to the ambiguous internal open juncture /s/-stop sequences in American English (e.g., “ place kin” vs. “ play skin”), that is, voice onset time (VOT) indicating different degrees of aspiration (e.g., long VOT for “ k in” vs. short VOT for “ s k in”) in connected speech contexts. A cross-splicing method was used to create two-word sequences (e.g., “ place kin” or “ play skin”) with matching VOTs (long for “ k in”; short for “ s k in”) or mismatching VOTs ( short for “ k in”; long for “ s k in”). Participants ( n = 20) heard the two-word sequences, while looking at computer displays with the second word in the left/right corner (“ KIN” and “ SKIN”). Then, listeners’ click responses and mouse movement trajectories were recorded. Click responses show significant effects of VOT manipulation, while mouse trajectories do not. Our results show that stop-release information, whether temporal or spectral, can (mis)guide listeners’ interpretation of the possible location of a word boundary between /s/ and a following stop, even when other aspects in the acoustic signal (e.g., duration of /s/) point to the alternative segmentation. Taken together, our results suggest that segmentation and lexical access are highly attuned to bottom-up phonetic information; our results have implications for a model of spoken language recognition with position-specific representations available at the prelexical level and also allude to the possibility that detailed phonetic information may be stored in the listeners’ lexicons.