Anticipatory velar lowering: a coproduction account

Feature spreading and coproduction models make fundamentally different assumptions about the nature and organization of speech motor control, and yet each model is supported by some, but not all, of the existing empirical data. This has led some researchers to conclude that speakers probably use alternative strategies at different times. This study suggests that the identification of coarticulatory influences requires the concurrent identification of intrinsic articulatory characteristics of the segment. Moreover, the evidence for feature spreading or variable coarticulation strategies derives from the misidentification of such intrinsic characteristics as context effects. This velar coarticulation study used a controlled comparison between CVnN and CVnC minimal pairs, where C is an oral consonant, Vn is any number of vowels, and N is a nasal consonant. Vocalic string duration was manipulated by varying the number of segments and speech rate, allowing us to alter the time between the onsets of vocalic and subsequent consonantal gestures. Velar lowering occurred in CVn sequences, whether or not a nasal consonant followed, and similar vocalic gestures were observed across minimally contrastive environments with and without the nasal consonant. Moreover, velar lowering for the nasal consonant began in close temporal proximity to the nasal murmur. These results strongly support the coproduction model and provide insight into previously conflicting reports.