Peripheral global neglect in high vs. low autistic tendency

Abstract

In addition to its core social deficits, autism is characterized by altered visual perception, with a preference for local percept in those high in autistic tendency. Here, the balance of global vs. local percepts for the perceptually rivalrous diamond illusion was assessed between groups scoring high and low on the Autism Spectrum Quotient (AQ). The global percept of a diamond shape oscillating horizontally behind three occluders can as easily be interpreted as the local percept of four line elements, each moving vertically. Increasing the luminance contrast of the occluders with respect to background resulted in an increase of initial global percept in both groups, with no difference in sensitivity between groups. Presenting the target further into the periphery resulted in a marked increase in the percentage of global perception with visual field eccentricity. However, while the performance for centrally presented diamond targets was not different between AQ groups, the peripheral global performance of the High AQ group was significantly reduced compared with the Low AQ group. On the basis of other imaging studies, this peripheral but not foveal global perceptual neglect may indicate an abnormal interaction between striate cortex and the Lateral Occipital Complex (LOC), or to differences in the deployment of attention between the two groups.

Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias

“…As already noted, abnormal biases in local/global visual processing have been reported in individuals diagnosed with an ASD (e.g., Plaisted et al, 1999; Spencer et al, 2000; Pellicano et al, 2005; Bolte et al, 2007) and have also been established in neurotypical populations with higher autism-like characteristics (e.g., Grinter et al, 2009; Almeida et al, 2010; Crewther and Crewther, 2014; Crewther et al, 2015; Cribb et al, 2016). Nevertheless, although it is suggestive, as Gregory and Plaisted-Grant (2013) have argued, it cannot be assumed that the same underlying mechanism can explain a given perceptual abnormality in clinical and non-clinical groups.…”

“…One suggestion is that enhanced perception of fine details in ASD drops off at a faster rate as stimuli move further from foveal vision, presenting as a form of “tunnel vision” in ASD (Robertson et al, 2013). Similarly, it has been shown that high and low autistic-trait groups did not differ in performance when viewing a bistable visual illusion, though high ASD-trait participants were less likely to report an initial global percept when the stimulus was presented further into the periphery (Crewther and Crewther, 2014). …”

“…It sought to determine whether anomalous biases in local/global processing previously found in consciously driven tasks on populations with higher autistic traits (e.g., Grinter et al, 2009; Crewther and Crewther, 2014), would persist without conscious awareness, perhaps reflective of a more generalized cognitive style. Results confirmed the hypothesis that lower autistic traits would be associated with a non-conscious global-level bias, and hence a cueing effect directed by the global level of a hierarchical arrow stimulus.…”

“…For example, it has previously been shown that unaffected siblings of individuals with an ASD show similar atypical eye-fixation patterns to faces as well as similar reductions in amygdala volume (Dalton et al, 2007). In particular, there is evidence for a similar pattern of anomalous local/global visual processing in populations with sub-clinical range autism traits (e.g., Grinter et al, 2009; Almeida et al, 2010; Crewther and Crewther, 2014; Crewther et al, 2015) suggesting a continuum between clinically diagnosed ASD and typically developing individuals with higher autism-like characteristics. These findings also suggest that similar neural mechanisms might be underpinning the perceptual and cognitive styles in clinical and subthreshold ASD populations.…”

Orientation-specific surround suppression in the primary visual cortex varies as a function of autistic tendency

“…The AQ is a questionnaire that was designed to measure the degree of autistic tendency in adults with typical intelligence, applicable to individuals with high-functioning autism or Asperger’s disorder, as well as NT individuals without an ASD diagnosis. Similar to studies of individuals with ASD, studies investigating perceptual processing as a function of AQ have shown that individuals who score high on the AQ (i.e., who have high autistic tendencies) exhibit increased sensory sensitivities (Robertson and Simmons, 2013 ) as well as enhanced local and reduced global perception across a range of tasks (e.g., Bayliss and Tipper, 2005 ; Sutherland and Crewther, 2010 ; Crewther, 2011 ; Kasai and Murohashi, 2013 ; Crewther and Crewther, 2014 ). For example, when manipulating the saliency of global and local letters by either blurring the display (i.e., enhancing global saliency) or randomly coloring the individual local letters (i.e., enhancing local saliency), Sutherland and Crewther ( 2010 ) showed that individuals with higher AQ scores were less able to ignore the salient local elements relative to individuals with lower AQ scores.…”