Perception of sibilants by preschool children with overt and covert sound contrasts

Abstract

Purpose: This study explores the role of overt and covert contrasts in speech perception by children with speech sound disorder (SSD). Method: Three groups of preschool-aged children (typically developing speech and language [TD], SSD with /s/~/ʃ/ contrast [SSD-contrast], and SSD with /s/~/ʃ/ collapse [SSD-collapse]) completed an identification task targeting /s/~/ʃ/ minimal pairs. The stimuli were produced by 3 sets of talkers: children with TD, children with SSD, and the participant himself/herself. We conducted a univariate general linear model to investigate differences in perception of tokens produced by different speakers and differences in perception between the groups of listeners. Results: The TD and SSD-contrast groups performed similarly when perceiving tokens produced by themselves or other children. The SSD-collapse group perceived all speakers more poorly than the other 2 groups of children, performing at chance for perception of their own speech. Children who produced a covert contrast did not perceive their own speech more accurately than children who produced no identifiable acoustic contrast. Conclusion: Preschool-aged children have not yet developed adultlike phonological representations. Collapsing phoneme production, even with a covert contrast, may indicate poor perception of the collapsed phonemes.