Eye-tracking explorations of attention to faces for communicative cues in Autism Spectrum Disorders

Abstract

Background Individuals with Autism Spectrum Disorder (ASD) have been reported to show socio-communicative impairments which are associated with impaired face perception and atypical gaze behaviour. Attending to faces and interpreting the important socio-communicative cues presented allows us to understand other’s cognitive states, emotions, wants and desires. This information enables successful social encounters and interactions to take place. Children with ASD not attending to these important social cues on the face may cause some of the socio-communicative impairments observed within this population. Examining how children with ASD attend to faces will enhance our understanding of their communicative impairments. Aim The present thesis therefore aimed to use eye-tracking methodology to examine attention allocation to faces for communicative cues in children with ASD. Method The first line of enquiry examined how children with ASD (n = 21; age = 13y7m) attended to faces presented within their picture communication systems compared to typically developing children matched on chronological age, verbal ability age and visuo-spatial ability age. The next investigation was conducted on the same group of children and examined how children with ASD attended to faces of different familiarity including, familiar, unfamiliar and the child’s own face. These faces were also presented with direct gaze or averted gaze to investigate how this would impact on the children’s allocation of attention. The final exploration highlighted how children with ASD (n = 20; age = 12y3m) attended to socially salient information (faces) and non-socially salient information (objects) presented within social scenes of varying complexity, compared to typically developing controls. Again groups were matched based on chronological age, verbal ability age, and visuo-spatial ability age. Results Children with ASD were shown to allocate attention to faces presented within their picture communication symbols similarly compared to their typically developing counterparts. All children were shown to fixate significantly longer on the face images compared to the object images. The children with ASD fixated for similar amounts of time to the eye and mouth regions regardless of familiarity and gaze direction compared to their controlled matches. All groups looked significantly longer at the eye areas compared to the mouth areas of the faces across all familiarity types. The children also fixated longer on the eye and mouth regions of direct gazing faces compared to the regions presented on the averted gazing faces. The children with ASD fixated on the faces and objects presented within social scenes similar to their typically developing counterparts across all complexity conditions. The children were shown to fixate significantly longer on the objects compared to the faces. Conclusions Children with ASD showed typical allocation of attention to faces. This suggests that faces are not aversive to them and they are able to attend to the relevant areas such as eye and mouth regions. This may have been influenced by the inclusion of high functioning children with ASD. However these results may also suggest that attention allocation and gaze behaviour are not the only factors which contribute to the socio-communicative impairments observed in ASD.