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

Yukari Takarae,Danielle J Harvey,Heather M Shapiro,Margarita H Cabaral,Tony J Simon

doi:10.1186/1866-1955-4-5

Yukari Takarae, Danielle J Harvey + Show 3 more

Open Access

https://doi.org/10.1186/1866-1955-4-5

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Abstract

BackgroundChromosome 22q11.2 deletion syndrome (22q11.2DS) results from a 1.5- to 3-megabase deletion on the long arm of chromosome 22 and occurs in approximately 1 in 4000 live births. Previous studies indicate that children with 22q11.2DS are impaired on tasks involving spatial attention. However, the degree to which these impairments are due to volitionally generated (endogenous) or reflexive (exogenous) orienting of attention is unclear. Additionally, the efficacy of these component attention processes throughout child development in 22q11.2DS has yet to be examined.MethodsHere 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.ResultsWe 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.ConclusionsThese 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.

Highlights

Chromosome 22q11.2 deletion syndrome (22q11.2DS) results from a 1.5- to 3-megabase deletion on the long arm of chromosome 22 and occurs in approximately 1 in 4000 live births
Children with 22q11.2DS had significantly larger cue cost when compared to typically developing (TD) children on endogenous (P < 0.001), but not exogenous trials (P = 0.10)
There was no difference in performance by age for TD children on endogenous trials (P = 0.99)

Summary

Introduction

Chromosome 22q11.2 deletion syndrome (22q11.2DS) results from a 1.5- to 3-megabase deletion on the long arm of chromosome 22 and occurs in approximately 1 in 4000 live births. 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]. Simon recently proposed that underlying impairments in attention may subserve many of the other cognitive impairments in children with 22q11.2DS [11] In this view, the atypical development of attentional processes, mediated by the genetics of the disorder, cascades into impairments in magnitude and numerical processing. A better understanding of attentional development in children with 22q11.2DS is critical for identifying an endophenotype of the disorder that is potentially a root of their cognitive impairments and could be targeted early in development for therapeutic intervention

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