Rett syndrome (RS) and profound intellectual disability: cognitive and communicative similarities and differences.

The communicative and cognitive behaviours of a group of 10 girls with Rett syndrome (RS) were compared with those of a group of girls with non-Rett profound intellectual disability (NPID). The results suggest that the girls with RS were a comparatively homogenous group demonstrating similar cognitive patterns and fewer communicative behaviours, communicative functions, and total numbers of inferred communicative acts than the NPID group. Fewer girls with RS were intentionally communicating to communicative partners. Implications of these findings will be discussed in this paper.