Differences in the perception of segmental contrasts by native and non-native listeners have been formalized as the results of language-specific weightings of acoustic cues in their perception grammar (e.g., Escudero & Boersma, 2004). However, less attention has been paid to the weighting of prosodic cues. This study investigated the relative importance of four prosodic cues – duration, pause, pitch, and intensity – in the resolution of syntactic ambiguity by English native speakers and Korean ESL speakers. In a processing experiment, two groups of participants listened to English sentences with relative clause attachment ambiguity (e.g., Jennifer blackmailed the boss of the clerk who was dishonest), differing in the presence/absence of the four prosodic cues for disambiguation. Then, they chose a more appropriate interpretation of the sentence (e.g., Q: Who was dishonest? Choices: the boss or the clerk). The results indicated that English speakers weighted pause and pitch cues heavily than lengthening and intensity, while pause was the only heavily weighted cue for Korean speakers. This is in line with a previous production study, which found that in English, RC attachment is disambiguated by the combination of boundary cues (pause) and head prominence cues (pitch and intensity), but in Korean, the ambiguity is mainly resolved by boundary cues (lengthening and pause) (Baek, 2019). Thus, Korean speakers’ weaker use of pitch compared to English speakers is likely an L1 influence. It suggests that, similarly to segmental cues, prosodic cues are weighted differently across languages, which influences second language sentence processing.
