Developmental changes in the cognitive and educational profiles of children and adolescents with 22q11.2 deletion syndrome.
Tobia V., Brigstocke S., Hulme C., Snowling MJ.
BACKGROUND: 22q11.2 deletion syndrome (22q11DS) is the most common microdeletion syndrome in humans. The presence of learning difficulty is reported in the majority of individuals with 22q11DS, but there is considerable heterogeneity in cognitive and educational profiles and in the age-related changes. METHOD: Verbal, non-verbal and spatial abilities, and educational attainment of 18 children and adolescents with 22q11DS were assessed at two time points 5 years apart. RESULTS: There was a decline in full-scale IQ, with a sharper decline in verbal than non-verbal skills, whereas spatial abilities remained stable over time. Individual profile analysis revealed discrepancies between full-scale IQ and reading skills, suggestive of "hyperlexia," for more than two-thirds of participants. CONCLUSIONS: The relative strength in verbal ability observed in 22q11DS is more apparent when children are younger, and a more even cognitive profile is observed in older children and adolescents. Educational attainments keep pace with development, and literacy skills are globally higher than might be expected from full-scale IQ.