Effects of morpheme boundaries on intergestural timing: evidence from Korean

This paper examines the effects of morpheme boundaries on intergestural timing, and demonstrates that low-level phonetic realization is influenced by morphological structure, i.e. compounding and affixation. It reports two experiments, one using electromagnetic midsagittal articulography (EMA) and one electropalatography (EPG), examining Korean data. The results of the EMA study show that intergestural timing is less variable for adjacent gestures across the word boundary inside a lexicalized compound than inside a nonlexicalized compound, and inside a monomorphemic word than across a morpheme boundary. The EPG study (which examined the timing in palatalization of a coronal) shows that both [ti] and [ni] have more variability in gestural timing when heteromorphemic than when tautomorphemic. Furthermore, the phonetic details of gestural overlap shed light on the asymmetry on palatalization between tautomorphemic and heteromorphemic gestural sequences (e.g. ni vs. n-i), presumably driven by paradigmatic contrast and preference of overlap. In short, what emerges from two experiments is that gestures are coordinated more stably within a single lexical item (a morpheme or a lexicalized compound) than across a boundary between lexical items. In accounting for the stability of intergestural timing within a lexical entry, several hypotheses were discussed including the Phase Window, Bonding Strength, Phonological Timing and Extended Phase Window model newly proposed here. The implication is that the morphological structure may be encoded in the phonetic realization, as is the case with other linguistic structure (e.g. prosodic structure).