Abstract
This study examines how individual prosodic cues contribute to the prediction of syntactic structure during English listening comprehension by Japanese EFL learners. Spoken language comprehension relies on multiple sources of information, and prosody plays a crucial role when segmental cues are insufficient. While previous research has often treated prosody as a single construct, the present study focuses on the differential roles of pitch, duration, and pauses in online sentence processing. Using a gating paradigm, Japanese university students listened to temporarily ambiguous English sentences based on the late/early closure principle. Speech stimuli were presented incrementally under two conditions: natural speech with intact prosody and speech with flattened fundamental frequency (F0). Participants judged sentence structure based on shared acoustic input, and accuracy data were analyzed using generalized linear mixed-effects models. The results revealed a significant interaction between prosodic condition and sentence structure at a critical gate. In the natural speech condition, learners utilized durational cues such as phrase-final lengthening to predict syntactic structure. In contrast, under flattened F0 conditions, the use of durational information was disrupted, and learners relied primarily on pauses, and no significant effect of listening proficiency was observed. These findings suggest that pitch information supports the perception and interpretation of durational cues, indicating that prosodic elements function interactively rather than independently in L2 sentence processing.
