Perceptual speech intelligibility and speech production variability in Mandarin-speaking children with cerebral palsy

Abstract

Perceptual speech intelligibility index can provide an objective standard for evaluating how speech deficiencies affect listeners’ judgments. This study investigated the effective variables for assessing speech intelligibility in Mandarin-speaking children with cerebral palsy. Acoustic measurements include vowel working space, vowel duration, pitch variation, and intensity variation of speech samples collected from picture naming tasks in two children with cerebral palsy (CP) and two typically developing children (TD) at four years old. Only clear word productions in terms of perceptual judgment and vowel formant display were incorporated to secure the reliability of data analysis. For speech intelligibility, eight judges were recruited to record the words they heard from the speech samples. Major findings are: (1) CP children had a smaller vowel space area due to limited control of tongue compared to TD children; (2) CP children showed longer vowel duration because they spent more time producing speech d...