Autism Spectrum Disorders (ASDs) are characterised by impairments in social interaction and communication, and restricted interests or repetitive behaviours. Autism traits are theorised to lie on a continuum throughout the general population, with individuals with a clinical diagnosis at one extreme. Those with high levels of autism traits in the general population have been found to display similar characteristics to those with ASD, but to a lesser extent. Differences in visual attention to social and non-social information are thought to contribute to the characteristic behaviours in autism. Whilst social attention may be diminished in ASD, ASD may also be associated with an increase in attention towards objects that are of circumscribed interest. The present thesis investigated visual attention to social and non-social objects in participants with ASD and those from the general population with high and low autism traits, to investigate whether differences in social and non-social visual attention relate to the autism spectrum. Dot probe, peripheral cueing, and eye tracking tasks were used to explore different elements of visual attention, including orienting and disengaging. Overall, social objects captured attention more than non-social objects, revealing the high salience of social information. Participants with high levels of autism traits and a diagnosis of ASD showed reduced social attention in the dot probe and eye tracking tasks, but not the peripheral cueing experiment. Across all experiments, there was no evidence to suggest that the autism spectrum was related to attentional biases towards objects related to circumscribed interests. However, other non-social stimuli appeared to capture attention to a greater extent across the spectrum. The differences in social attention in those with higher autism traits and ASD appeared greater when more stimuli were competing for attention, suggesting reduced social attention may involve interference from non-social stimuli in the visual field. This may indicate that attention is guided more by visual properties of the stimuli than their semantic meaning in the autism spectrum.
|Date of Award||21 Aug 2015|
|Supervisor||Chris Ashwin (Supervisor) & Mark Brosnan (Supervisor)|