Communication is the act of sending and receiving messages. It is usually accomplished by gesture, facial expression, and spoken or written language. Skilled communication allows us to share our ideas, thoughts, and feelings. In childhood it facilitates the development of relationships and access to education, leisure activities, and later, employment. Children with cerebral palsy (CP) often experience communication difficulties and recent epidemiological studies have suggested that communication limitations are associated with motor impairments in the first years of life and with both motor and cognitive skills in later childhood and in the high school years. Type of CP has also been observed to predict communication function. More severe communicative limitations have been observed for children with dyskinetic forms of CP than with spastic type. Communication difficulties in bilateral spastic and dyskinetic CP may be due to motor speech impairment alone, but may also be influenced by accompanying intellectual impairments.
Vos et al. have prospectively studied the communication of children with CP in four different age cohorts and have modelled communication trajectories for children with dyskinetic CP, and unilateral and bilateral spastic CP (with and without intellectual impairment) from 2 to 16 years. Their results support those of Himmelman et al., and suggest that across childhood the strongest predictor for expressive, face-to-face communication is CP type and distribution, with unilateral spastic CP associated with best outcome. After an initial lag, the children they tracked who had spastic type CP without intellectual impairment acquired expressive skills similar to their peers with typical development. Children with non-spastic type who did not have intellectual impairment continued to lag behind, potentially due to the severity of their dysarthria.
Vos et al. measured expressive communication using the Vineland Adaptive Behaviour Scales, which mainly reports interaction using language. Items on this assessment could have been passed using spoken language or language produced using augmentative and alternative communication (AAC) systems. It would be interesting to ascertain the impact of AAC on children's expressive communication in this study. Information on how many children used AAC, the types of systems they used, and the complexity of messages they produce would be helpful. Without the use of such systems mean expressive communicative performance may have been lower, but by what degree is impossible to speculate. Such data could provide important support for the implementation of AAC, which is far from universal, even in countries with relatively well developed and resourced health, education, and welfare systems such as the UK.
Intellectual impairment was the strongest predictor of receptive communication. These results suggest that language difficulties in CP are strongly influenced by general cognition and that language disorder is not common in this group of children, which has previously been hypothesized. It is noticeable that the raw scores of children with bilateral spastic CP were reduced in middle adolescence. This may be a real effect or may, in this study, be due to samples of children being studied within each cohort in a design that was both cross-sectional and prospective. Further prospective research, with children studied for longer periods or with potentially larger samples, is needed to examine if the trajectories observed by Vos et al. can be replicated, and indeed if receptive scores may continue to change in later adolescence.
Vos et al. also provide valuable information on written language development. Learning to read and spell is particularly important in our technological world; information technology can create vast opportunities for learning, leisure, and employment. However, access to information technology and social media is heavily dependent on the written word. This is the first epidemiological study to track prospectively the literacy development of young people with CP. It is encouraging to observe that children without intellectual impairment achieved literacy scores similar to their peers with typical development. It is hoped that the PERRIN+ Study cohorts in the Netherlands are studied further and new cohorts are also observed to investigate the acquisition and use of literacy by young people with CP, especially those who have intellectual impairment. Future research could also ascertain the causes of literacy difficulties. Some children's literacy may be commensurate with their general intellectual development. Other children's literacy may be influenced by difficulties in phonological awareness and verbal working memory.[5, 6] Further information on literacy acquisition could help us provide tailored literacy instruction and help young people increase their access to technology and potentially enhance their participation in social, educational, and civic life.