Developmental language trajectories: Differences between pre-schoolers with 22q11.2 Deletion Syndrome and typically developing pre-schoolers
Summary
The 22q11.2 Deletion Syndrome (22q11DS) is characterized by large phenotypic variation, but research suggests that the language development of children with 22q11DS is commonly delayed compared to typically developing (TD) children. However, little is known about the developmental language trajectories of children with 22q11DS. The aim of the current study is to investigate whether the language proficiency of pre-schoolers with 22q11DS develops differently compared to TD children by administering and analysing the standardized language measures (comprising different language domains) of children with 22q11DS aged 3;0-6;6 years old on two time points (six months apart). The children’s scores were compared with a matched TD group at the first test moment, and with norm scores at both test moments. The results showed that children with 22q11DS have an overall lower language proficiency than their peers. Children with 22q11DS showed improvement for both receptive and expressive vocabulary and for sentence comprehension between T1 and T2. Furthermore, age corrected norm scores did not differ between T1 and T2, indicating that children with 22q11DS develop at a comparable rate as their TD peers on all subdomains. Exploratory analyses suggest that children with 22q11DS have more difficulty keeping up with the developmental pace of the norm group for expressive, than for receptive language skills. These findings indicate that developmental language trajectory is language domain dependent in this population. It is recommended to start speech-language therapy at a young age for children with 22q11DS and to monitor their language development throughout childhood.