AN ELECTROPALATOGRAPHIC STUDY OF STOP CONSONANT CLUSTERS

This is an electropalatographic investigation of coarticulation for he terosyllabic stop consonant clusters in American English and Catalan V CCV sequences. The heterorganic clusters under analysis were [tk], [kt ], [tp], [pt], [kp], [pk]. Evidence for gestural overlap between the t wo adjacent consonants in the cluster is found quite systematically ab out the closure midpoint and, less so, at C1 onset and at C2 offset. O verlap occurs between constrained and unconstrained lingual regions (e .g., [p] is produced with more alveolar contact than usual when preced ed by [t]) and gives rise to blending between tongue front and tongue dorsum activity during the production of lingual clusters [kt] and [tk ]. Clusters are equally sensitive to vowel-dependent effects at all mo ments in time during the closure period. Such effects are quite large for clusters involving lingual [t] or [k] and non-lingual [p] and quit e small for clusters made of the two former lingual stop consonants. T hese data on consonant- and vowel-dependent coarticulatory effects sug gest that stop clusters are produced as highly cohesive production uni ts. A constraint for anticipatory vowel-dependent effects to occur at the cluster midpoint but not so at cluster onset can be taken in suppo rt of a time-locked model of coarticulation. Speaker-dependent trends were also observed.