Prosody generally refers to intonation, stress pattern, loudness variations, pausing, and rhythm. We express prosody by varying pitch, loudness, and duration. A person who does not vary any of these parameters will sound robotic. We frequently come across characteristics of childhood apraxia of speech (CAS) as including robotic speech or some other element of disordered prosody. What may account for this observation?
It has been my belief that when a child with CAS is focusing on correct articulation, some aspect of prosody inevitably suffers. Treatment techniques commonly used with children with CAS often encourage clear articulation at the cost of normal prosody. One example would be a child who is focusing on the correct sequencing of syllables for a multisyllabic word or utterance. This child may be trained to compensate by speaking one syllable at a time, causing the speech to sound choppy and monotone. Another technique is to work on decreasing the rate of speech so that the child has time to plan the movement sequence for speech. Children with CAS have been observed to incorporate a target phoneme at slower than normal speech rate but not able to produce it at normal speech rate. This in turn, can alter word stress. For example, in the word ‘teacher’, the first syllable should be stressed. However, if ‘r’ takes a lot of effort and time to produce correctly, we’ll hear the second syllable as being stressed.
It’s interesting to note that such disturbances are often not evident in spontaneous speech. My observation has been that younger children who have a lot of sound omissions and are not paying attention to correct articulation tend to have more normal prosody than children who are attempting correct articulation. Once speech becomes more automatic, prosody tends to improve. It is important to note that while decreasing rate is extremely important, the therapist should also try to keep intonation as normal as possible.
(Amy Meredith, Ph.D., CCC-SLP is currently an Assistant Professor at the Washington State University. She is an experienced clinician who has worked in the public school, hospital, and private practice settings. Her primary clinical and research interest is in children with motor speech disorders. She has published and presented her research on children with apraxia at national conferences. She has also given numerous workshops for practicing speech-language pathologists on assessment and treatment of childhood apraxia. Dr. Meredith is a member of the professional advisory board for CASANA)