Probing the syllabic structure of words using the audio-visual McGurk effect

Many studies have shown that a syllable has an internal hierarchical structure and is made up of two main constituents: the consonantal onset and the rhyme. Most experiments to test the cognitive reality of the syllable in the mental models of humans have involved word games using words with concealed parts. Here we outline an alternative way of testing for syllabic structure using McGurk fusion. The experiments develop a method for locating syllable boundaries in polysyllabic words, based on the coda-onset fusion rate differences found in our earlier work with monosyllabic words. For the sake of simplicity, the fusion rate measurements are made on polysyllabic words in which an internal consonantal site is given audio-visual incongruence. A word-internal site may be the coda of a first syllable or the onset of a second syllable. The aim of the research was to determine whether a fusion in the word- medial consonant of polysyllabic words confirms the traditional or another syllabification scheme. The results from our first study show that the McGurk fusion rates can be used to locate syllable boundaries in polysyllabic words. The findings show that in 65% of the English words investigated the coda of the traditional morphological stem has the fusion-rate behaviour of an empirical coda.