Increased Sensitivity to Mirror Symmetry in Autism

Abstract

Can autistic people see the forest for the trees? Ongoing uncertainty about the integrity and role of global processing in autism gives special importance to the question of how autistic individuals group local stimulus attributes into meaningful spatial patterns. We investigated visual grouping in autism by measuring sensitivity to mirror symmetry, a highly-salient perceptual image attribute preceding object recognition. Autistic and non-autistic individuals were asked to detect mirror symmetry oriented along vertical, oblique, and horizontal axes. Both groups performed best when the axis was vertical, but across all randomly-presented axis orientations, autistics were significantly more sensitive to symmetry than non-autistics. We suggest that under some circumstances, autistic individuals can take advantage of parallel access to local and global information. In other words, autistics may sometimes see the forest and the trees, and may therefore extract from noisy environments genuine regularities which elude non-autistic observers.

Oblique Orientation Discrimination Thresholds Are Superior in Those with a High Level of Autistic Traits

“…In addition, we found that those with higher AQ scores showed a smaller oblique effect. This finding echoes previous work on mirror symmetry in which individuals with autism were shown to have a reduced oblique effect (Perreault, Gurnsey, Dawson, Mottron & Bertone, 2011).…”

Veridical mapping in the development of exceptional autistic abilities

“…One EPF principle (Mottron et al, 2006a, p. 35), "perceptual expertise underlies savant syndrome," is a foundation for the current paper. Subsequent findings of superior symmetry perception (Perreault et al, 2011), superior mental rotation (Falter et al, 2008;Soulières et al, 2011a), and a superior role of perception in intelligence ) furthered the EPF premise that perception in autistic individuals is capable of sophisticated operations. In the same direction, an associative, rather than a primary, perceptual region displays enhanced fMRI activity at the group level in autism (Samson et al, 2011b).…”

“…Both tasks involve the mapping of a probe to targets presented in a noisy environment. The relevant low-level visuo-perceptual foundations for enhanced pattern detection are manifested in superior autistic detection of symmetry in noise (Perreault et al, 2011). This is associated with an enhanced role of perception in high-level operations, as displayed by non-savant autistics who typically combine faster problem solving with greater activity in visual expertise cortical regions.…”

Incompleteness, aesthetic sensitivity, and the obsessive-compulsive need for symmetry

“…Other than BDD (Lambrou et al, 2011), the only disorder in which perceptual biases for symmetry have been reliably observed is autism (e.g., Perreault et al, 2011). Another point of intersection between the OC and autism spectra is sensory-emotional dysregulation (e.g., Ferrão et al, 2012;Kern et al, 2006;Taylor et al, 2014).…”

“…It would also aid evaluation of the usefulness of prevailing cognitive-appraisal models of OC symptoms, which hold that atypical responses to symmetry/asymmetry are to be expected only insofar as it is appraised as personally salient (see Rachman, 1997Rachman, , 1998. Finally, it would permit comparisons and theoryknitting among OCD and other psychopathologies characterized by perceptual sensitivity to symmetry, such as body dysmorphic disorder (BDD) (see and the autism spectrum (e.g., Perreault, Gurnsey, Dawson, Mottron, & Bertone, 2011).…”