Prosodic boundary information modulates phonetic categorization.

Categorical perception experiments were performed on an English /b-p/ voice onset time (VOT) continuum with native (American English) and non-native (Korean) listeners to examine whether and how phonetic categorization is modulated by prosodic boundary and language experience. Results demonstrated perceptual shifting according to prosodic boundary strength: A longer VOT was required to identify a sound as /p/ after an intonational phrase than a word boundary, regardless of the listeners' language experience. This suggests that segmental perception is modulated by the listeners' computation of an abstract prosodic structure reflected in phonetic cues of phrase-final lengthening and domain-initial strengthening, which are common across languages.