Attention and Intermodal Processing in Autism Spectrum Disorder

Background: Children with ASD often have challenges with different aspects of attention. This includes disengaging from one stimulus to another, as well as with intermodal processing (integrating visual and auditory information). Even young infants orient their heads and search visually for sounds that are presented near their ears (Arterberry & Kellman, 2016). Because these processes are so vital and apparent in early development, Posner (1988) hypothesized that they would be involved in selective attention. In this study we examine the concurrent development of these skills in children with and without ASD.

Objectives: In this study we examined whether difficulties in shifting and disengaging attention are associated with weak intermodal processing abilities in children with ASD. If these abilities are related, this likely suggests that they develop intertwined together. The findings provide insight into whether strengths and limitations in these abilities are related in typical development and, more particularly, in ASD, where attention skills are more varied. In addition, parent reports often differ from behavioural measures of attention. The observed attention responses as well as intermodal processing are compared with parent reports of attention.

Methods: 14 children with ASD were compared to 19 typically developing children. Children ranged from 6 to 16 years of age. They completed an intermodal processing task using the preferential looking paradigm. Specifically, participants were presented with 4 screens, where only 1 screen had a video track synchronous with the audio track, while the other screens had asynchronous video and audio. They were also presented with an attention task where 4 screens appeared sequentially, either immediately following one another (shifting) or with a slight period of overlap (disengaging). During these tasks, participant eye gazes were recorded using eye-tracking technology. Parents were also given a common report of attention (Conners-3).

Results: Overall, for typically developing children, shifting attention, but not disengaging, and intermodal processing were related (|r| = 0.56 - 0.65, all p < 0.05). However, in children with ASD, these abilities were not significantly related (|r| = 0.19 - 0.35, all p > 0.10). Parent reports of attention correlated with shifting and disengaging abilities (r = 0.57 - 0.69, p < 0.05) in the ASD group only.

Conclusions: These results indicate that in typical development shifting attention is related to the ability to efficiently integrate information from different senses. However, for children with ASD these abilities were not related to each other. This suggests that if impairment occurs in one of these areas, the other may be preserved or may be differentially affected. In the present study, while some children with ASD had impairments in both attention skills and intermodal processing, these degree of the deficits were not consistent on the two tasks. This may mean that different aspects of selective attention develop independently in those children with specific deficits. In addition, parent reports of attention were consistent with observed behaviors in the ASD group only. The lack of association in the non-clinical group may be due to reduced variability in a typical sample.