Glasgow Gloom or Leeds Glue? Dialect-Specific Vowel Duration Constrains Lexical Segmentation and Access

Timing cues are important in many aspects of speech processing, fromidentifying segments to locating word and phrase boundaries. They vary across accents, yet representation and processing of this variation are poorly understood. We investigated whether an accent difference in vowel duration affects lexical segmentation and access. In Glasgow English (GE), /i u e o/ are shorter than in Leeds English (LE), especially for /i u/ before voiced stops and nasals. In a word-spotting experiment, GE and LE participants heard nonsense sequences (e.g. pobegloomezh) containing embedded words (gloom, glue), with segmental qualities intermediate between GE and LE. Critical vowel durations were manipulated according to accent (GE-appropriate vowels shorter than LE-appropriate ones) and phonological context (vowels shortest before voiceless stops < voiced stops/nasals < voiced fricatives). GE participants generally spotted words like gloom more accurately with GE-appropriate than LE-appropriate vowels. LE participants were less accurate than GE participants to spot words like gloom with GE-appropriate vowels, but more likely to spot embeddings like glue. These results were broadly as predicted based on the accent differences, but depended less than expected on the accent-specific phonological constraints. We discuss theoretical implications regarding the representation of duration and the time course of lexical access.