The substitution of [s] for aspirated targets: perceptual and acoustic evidence from Cantonese

Abstract

The substitution of [s] for word-initial aspirated targets was examined in a Cantonese-speaking pre-school child. Perceptual analysis showed that the child produced [ph] accurately, but substituted [s] for /th/, /tsh/ and /kh/. Acoustic analysis revealed no subphonemic contrast between the target /s/, and the substituted [s] for /th/, /tsh/ and /kh/. The unusual substitution of [s] for aspirated lingual targets, and the lack of a subphonemic contrast among [s] productions were described in terms of feature geometry. The target feature patterns of [−continuant, +spread] were produced as [+continuant, +spread], with maintenance of the default place feature (coronal). It is proposed that the child had immature motor control of the coordination of supralaryngeal and laryngeal movements. Examination of the child's productions of aspirated lingual targets at pre-, mid- and post-therapy revealed that compensatory articulation changed over time as the child learned to coordinate laryngeal and oral movements.