Coordination of lip and jaw movements in children with CP

Does reduced movement of lip and jaw contribute to difficulties understanding some children with CP? According to Ignatius Nip from San Diego State University, yes. Nip explores the development of speech from a kinematic perspective - that is the study of motion - and in this case the movement of jaw and lips. In his latest publication, he investigated how coordination between lips and jaw affect speech production and intelligibility in children with CP. As part of this study, he also intended to find out whether the complexity of an articulatory movement - there is a difference between repeating sentences and repeating the same syllable - plays a role as well.

To answer these questions Nip invited 12 children with spastic CP and 12 typically-developing kids into his lab. Reflective markers were put on the children’s faces to capture the movements of upper lip and jaw, lower lip and jaw and upper, and lower lips when repeating syllables and sentences. Temporal and spatial movement were measured, that is the timing of the movements as well as how well the movements fit together.

The study found that the children with CP had difficulties coordinating the movements between upper and lower lips. This is likely to affect sounds that are produced using both lips such as [b]. The timing for moving upper lip and jaw was also affected. With regard to the complexity of the speech movements the results showed that the coordination of lips and jaw was more precise for the sentences than for the syllables. In addition, there was a clear relation between effective movement coordination and intelligibility. That is, the children who showed signs of dysarthria – reflected in their intelligibility scores – were less successful in coordinating their movements. Children with CP and dysarthria do seem to move their lips and jaw differently than their typically-developing peers. This difference in articulatory movement is measurable and there is a chance that information on articulatory performance can be used to help describe dysarthria problems in children with CP…provided relevant resources are in place...

Nip, I.S.B (2015). Interarticulator coordination in children with and without cerebral palsy. Developmental Neurorehabilitation. Early online, 1-13.