Relation of Anxiety on Attentional Flexibility and Attentional Disengagement in Children with Autism Spectrum Disorder: Results from the ABC-CT Feasibility Study

Background:

Attentional flexibility has been shown to differentiate infants at high risk for autism spectrum disorder (ASD) from infants at low risk for ASD (Elsabbagh et al., 2009). Similarly, children with anxiety have deficits in attentional flexibility, including difficulty disengaging attention between tasks (Eysenck & Calvo, 1992). Approximately 40% of children with ASD have a co-occurring anxiety disorder, a rate significantly higher than the 2.4% estimated in the general population (Costello et al., 2003). Despite the increased prevalence, little is known about factors that contribute to heightened rates of anxiety in children with ASD. Measuring attentional flexibility in school-aged children with a diagnosis of ASD and anxiety symptoms may inform how early attentional deficits contribute to the phenotype.

Objectives:

Our primary objective was to evaluate group differences in attentional flexibility and determine how anxiety symptoms in children with ASD relate to disengagement of attention.

Methods:

Typically developing (TD) children (n=26, M_years=6.6 SD=1.98) and children with ASD (n=19, M_years=8.25 SD=2.03), recruited from study NIMH# 1U19MH108206-01—PI: McPartland, viewed a central stimulus with an animated peripheral (target) stimulus as eye movements were recorded using an SR EyeLink 1000 Plus eye tracker. The following conditions were presented: 1. Baseline Condition, where the central stimulus disappears at precisely the same time as the appearance of the target stimulus; 2. Gap Condition, where the central stimulus disappears 200 ms before the target stimulus appears; and 3. Overlap Condition, where the central stimulus and target stimulus are presented at the same time. The principal dependent variable was average reaction-time (RT) of the first fixation toward the target. RT was log-transformed to normalize the spread of distribution. Anxiety symptoms were measured using the Behavior Assessment System for Children, Version 3 (BASC-3).

Results:

The ASD group had elevated scores of anxiety symptoms when compared to the TD group (t(43)= 3.44, p<.01). Average RT to the target stimuli in the ASD group (Baseline_M=5.46 Baseline_SD= .20, Gap_M=5.31 Gap_SD=.14, Overlap_M=5.63 Overlap_SD=.29) was faster than the TD group (Baseline_M=5.57 Baseline_SD=.17, Gap_M=5.42 Gap_SD=.19, Overlap_M=5.74 Overlap_SD=.23) in all conditions, with a marked speed in the baseline and gap conditions (Baseline_t(43)= -2.14, p=.04; Gap_t(43)= -2.14, p=.03; Overlap_t(43)= -1.4, p=.17). In the ASD group, anxiety symptoms negatively correlated with RT baseline average (r= -.5, p=.03).

Conclusions:

The ASD group had faster RTs to the target stimulus than the TD group in all three conditions, with particular speed in the baseline and gap conditions, suggesting temporal facilitation of attentional disengagement. Increased anxiety symptoms were related to faster engagement to the target stimulus in the baseline condition for the ASD group. This may be due to elevated rates of anxiety symptoms and thus increased vigilance and awareness of the overall environment. Further examination of attentional flexibility in children with anxiety and ASD may provide insight into the cognitive mechanisms of anxiety in this population and increased prevalence.