Sophia Linguistica, Vol. 53, pp. 49-76, 2005.
Perceptural weighting of syllable-initial fricatives for native Japanese adults and for children with persistent developmental articulation disorders
S. Hirai, K. Yasu, T. Arai and K. Iitaka
Background: Persistent developmental articulation disorder and language learning impairment are suspected to concur due to a speech processing deficit. The change in children’s perceptual strategies is proposed as an indicator of development of processing speech ability (Nittrouer & Studded-Kennedy, 1987). To diagnose a speech processing deficit and intervene in it early, in an attempt to identify a marker for the development of processing speech ability, we examine perceptual weight.
Methods: Forty-two native Japanese adults without speech disorder and 2 native Japanese children with persistent developmental articulation disorder and language learning impairment identified tokens from a /S (long s)/ – /s/ continuum followed by vocalic portions with formant transitions changing continuously from ones appropriate for /S (long s)/ to those for /s/.
Findings: Most adult participants weighted to fricative noises more than to formant transition in the same manner as the adult participants in Nittrouer and Miller’s study. However, as compared with most adult participants, a small number of adult participants and both children judged based more on the formant transitions than on the spectrum of the noise like Nittrouer’s 3- to 4-year-old children.
Interpretation: The perceptual weight assigned by adults suggested they did not perceive uniformly. The perceptual weight assigned by the children indicated that speech perception ability might develop differently from that of typically developing children because of deficits in speech perception.