Thursday, May 20, 2010
Franklin Hall B Level 4 (Philadelphia Marriott Downtown)
11:00 AM
Background: Autism Spectrum Disorder (ASD)is a pervasive neurodevelopmental disorder associated with a unique profile of social and emotional behaviour. The core symptomatology of autism highlights lack of social or emotional reciprocity, failure to develop age-appropriate relationships and lack of interest in the human face. The ability to judge facial expressions and derive other socially relevant information from faces is a fundamental requirement for normal reciprocal social interactions and interpersonal communication.
Objectives: The aim of this work was to investigate typical development of gaze behaviour during face and emotional expression perception on a wide number of subjects, using an eye-tracking system, and to identify dysfunction in patients with autism.
Methods: The study was conducted in 52 healthy children (aged 4 to 15 years) and 44 healthy adults (aged 18 to 35 years) and in 27 children with autism (aged 4 to 15) and 7 adults with autism (aged 18 to 35 years). The measurement of various parameters of visual path scans (fixation time, length of path scan, velocity of ocular path scan, exploratory strategy, pupil dilation) was performed during visual perception of neutral faces (with direct or averted gaze), emotional faces or virtual faces.
Results: Analyses of the path scan data revealed marked differences between groups. The autistic adults and children have spent less time on the core features areas of the faces (eyes, mouth and nose) than controls and more time on the rest of the face. No effect of emotion was evidenced. In all groups, the effect of ocular dominance had been shown on the exploratory strategy. This strategy was sensitive to the maturation for the normal children. The autistic groups (adults and children) presented atypical patterns of visual exploratory strategy of faces concerning fixation time, length of path scan, velocity, exploratory strategy and pupil dilation.
Conclusions: These results indicate disorganized exploration of face stimuli in autistic patients. These findings raise the possibility that altered visual exploration of faces may contribute to the social impairment that characterizes autism.
Objectives: The aim of this work was to investigate typical development of gaze behaviour during face and emotional expression perception on a wide number of subjects, using an eye-tracking system, and to identify dysfunction in patients with autism.
Methods: The study was conducted in 52 healthy children (aged 4 to 15 years) and 44 healthy adults (aged 18 to 35 years) and in 27 children with autism (aged 4 to 15) and 7 adults with autism (aged 18 to 35 years). The measurement of various parameters of visual path scans (fixation time, length of path scan, velocity of ocular path scan, exploratory strategy, pupil dilation) was performed during visual perception of neutral faces (with direct or averted gaze), emotional faces or virtual faces.
Results: Analyses of the path scan data revealed marked differences between groups. The autistic adults and children have spent less time on the core features areas of the faces (eyes, mouth and nose) than controls and more time on the rest of the face. No effect of emotion was evidenced. In all groups, the effect of ocular dominance had been shown on the exploratory strategy. This strategy was sensitive to the maturation for the normal children. The autistic groups (adults and children) presented atypical patterns of visual exploratory strategy of faces concerning fixation time, length of path scan, velocity, exploratory strategy and pupil dilation.
Conclusions: These results indicate disorganized exploration of face stimuli in autistic patients. These findings raise the possibility that altered visual exploration of faces may contribute to the social impairment that characterizes autism.