Perceptual Cue Weighting Matters in Real-Time Integration of Acoustic Information During Spoken Word Recognition

This study investigates whether listeners’ cue weighting predicts their real-time processing of asynchronous acoustic information as the speech signal unfolds over time. It does so by testing the time course of acoustic cue integration in the processing of Seoul Korean stop contrasts by native listeners. The current study further tests whether listeners’ cue weighting is associated with cue integration at the individual level. Seoul Korean listeners’ (n = 62) perceptual weightings of voice onset time (VOT, available earlier in time) and onset fundamental frequency of the following vowel (F0, available later in time) to perceive Korean stop contrasts were measured with a speech perception task (Experiment 1), and the timing of VOT integration in lexical access was examined with a visual-world eye-tracking task (Experiment 2). The group results revealed that the timing of VOT integration is predicted by listeners’ reliance on F0, with delayed integration of VOT in target-competitor pairs where F0 is a primary cue to process the stop contrast. At the individual level, listeners who relied more on F0 than on VOT showed later integration of VOT, further elucidating the relationship between cue weighting and the time course of cue integration. These results suggest that listeners’ real-time processing of asynchronous acoustic information in lexical activation is modulated by the informativeness of perceptual cues. As such, this study provides a nuanced perspective for a better understanding of listeners’ moment-by-moment processing of acoustic information in spoken word recognition.