The influence of visual saliency on fixation patterns in individuals with Autism Spectrum Disorders

Abstract

It is widely reported that individuals with Autism Spectrum Disorders (ASD) direct their attention in an atypical manner. When viewing complex scenes, typically developing individuals look at social aspects of scenes more rapidly than individuals with ASD. In the absence of a strong drive to extract social information, is something else capturing attention in these initial fixations, such as visually salient features? Twenty four high-functioning adolescents with ASD and 24 typically developing matched control participants viewed a series of indoor and outdoor scenes while their eye movements were tracked. Participants in both groups were more likely to fixate on salient regions in the first five fixations than later in viewing. Peak saliency at fixation occurred at fixation two for the typically developing participants but at fixation three for ASD participants. This difference was driven by typically developing participants looking at heads earlier than ASD participants – which are often visually salient. No differences between groups were observed for images in which the heads were not salient. We can therefore conclude that visual saliency impacts fixation location in a similar manner in individuals with ASD and those with typical development. It was found that social features in scenes (heads) captured attention much more than visually salient features, even in individuals with ASD.