Speech intelligibility and childhood verbal apraxia in children with Down syndrome.

Abstract

Many children with Down syndrome have difficulty with speech intelligibility. The present study used a parent survey to learn more about a specific factor that affects speech intelligibility, i.e. childhood verbal apraxia. One of the factors that affects speech intelligibility for children with Down syndrome is difficulty with voluntarily programming, combining, organising, and sequencing the movements necessary for speech. Historically, this difficulty, childhood verbal apraxia, has not been identified or treated in children with Down syndrome but recent research has documented that symptoms of childhood verbal apraxia can be found in children with Down syndrome. The survey examined whether and to what extent childhood verbal apraxia is currently being identified and treated in children with Down syndrome. The survey then asked parents to identify certain speech characteristics that occur always, frequently, sometimes or never in their child's everyday speech. There were 1620 surveys received. Survey results indicated that approximately 15% of the parents responding to the survey had been told that their child has childhood verbal apraxia. Examination of the everyday speech characteristics identified by the parents indicated that many more children are showing clinical symptoms of childhood verbal apraxia although they have not been given that diagnosis. The most common characteristics displayed by the subjects included decreased intelligibility with increased length of utterance, inconsistency of speech errors, difficulty sequencing oral movements and sounds, and a pattern of receptive language superior to expressive language. The survey also examined the impact of childhood verbal apraxia on speech intelligibility. Results indicated that children with Down syndrome who have clinical symptoms of childhood verbal apraxia have more difficulty with speech intelligibility, i.e. there was a significant correlation between childhood verbal apraxia and parental intelligibility ratings. Children with apraxia often do not begin to speak until after age 5. There was a significant correlation between speech intelligibility and age at which the child began to speak, i.e. children who began to speak after age 5 had lower parental intelligibility ratings. A diagnosis of difficulty with oral motor skills is more frequently given than a diagnosis of apraxia; 60.2% of parents had been given this diagnosis. According to survey results, it is rare (2%) for a diagnosis of childhood verbal apraxia to be made without a diagnosis of difficulty with oral motor skills.