Gestural timing and stability in hausa implosives

Abstract

Articulatory dynamics of glottalic consonants—ejectives and implosives—show strictly different intergestural timing patterns that those of pulmonic consonants. For example, oral constriction and vertical larynx gestures in Hausa have been shown to be sequentially produced for glottalic consonants and simultaneously produced for their pulmonic counterparts (Oh et al., ASA 2018, PaPE 2019). In the present work, we predict that glottalic consonants will exhibit tighter, more stable intergestural coordination than pulmonic consonants, due to the superordinate aerodynamic goal in glottalics—namely, that to generate a rapid oral air pressure change the vertical larynx action must begin during the oral closure interval. The current study examines data from three Hausa speakers producing voiced implosives and voiced plosives, using real-time MRI to obtain kinematic information on the oral constriction and the vertical larynx action. A region-of-interest analysis quantifies oral constrictions and a centroid analysis tracks vertical larynx actions. Findings confirm that intergestural timing patterns are contrastive between implosives and voiced stops. Moreover, results on relative timing stability, indexed by token-to-token variability and covariance relations between timing lags and gestural durations, indicate that the intergestural timing for implosives is more stable than for voiced stops. [Work supported by NIH and NSF.]