A cross-sectional study of the development of volitional control of spatial attention in children with chromosome 22q11.2 deletion syndrome

Here we compared the performance of a wide age range (7 to 14 years) of children with 22q11.2DS to typically developing (TD) children on a comprehensive visual cueing paradigm to dissociate the contributions of endogenous and exogenous attentional impairments. Paired and two-sample t-tests were used to compare outcome measures within a group or between groups. Additionally, repeated measures regression models were fit to the data in order to examine effects of age on performance.We found that children with 22q11.2DS were impaired on a cueing task with an endogenous cue, but not on the same task with an exogenous cue. Additionally, it was younger children exclusively who were impaired on endogenous cueing when compared to age-matched TD children. Older children with 22q11.2DS performed comparably to age-matched TD peers on the endogenous cueing task.These results suggest that endogenous but not exogenous orienting of attention is selectively impaired in children with 22q11.2DS. Additionally, the age effect on cueing in children with 22q11.2DS suggests a possible altered developmental trajectory of endogenous cueing.Chromosome 22q11.2 deletion syndrome (22q11.2DS) results from a 1.5- to 3-megabase microdeletion on the long (q) arm of chromosome 22 [1] and occurs in approximately 1 in 4000 live births [2,3]. Children with this disorder have a physical phenotype that might include cardiovascular abnormalities and cleft palate [4], in addition to mild to moderate learning impairments and a characteristic cognitive phenotype [5,6]. More specifically, the characteristic cognitive profile in most children with 22q11.2DS includes non-verbal impairments that stand in contrast to relative strengths in the verbal domain [7]. These non-verbal impairments include, but are not limited to, impairments in attention, spatial cognition, quantitative cognition, and arithmetical processing [8-10].Simon recently proposed that underlying impairments in attention may subserve many of the o