Eagle-Eyed Visual Acuity: An Experimental Investigation of Enhanced Perception in Autism

Autism Research Centre, Department of Psychiatry, University of Cambridge, Douglas House, Cambridge, United Kingdom.
Biological psychiatry (Impact Factor: 10.26). 01/2009; 65(1):17-21. DOI: 10.1016/j.biopsych.2008.06.012
Source: PubMed


Anecdotal accounts of sensory hypersensitivity in individuals with autism spectrum conditions (ASC) have been noted since the first reports of the condition. Over time, empirical evidence has supported the notion that those with ASC have superior visual abilities compared with control subjects. However, it remains unclear whether these abilities are specifically the result of differences in sensory thresholds (low-level processing), rather than higher-level cognitive processes.
This study investigates visual threshold in n = 15 individuals with ASC and n = 15 individuals without ASC, using a standardized optometric test, the Freiburg Visual Acuity and Contrast Test, to investigate basic low-level visual acuity.
Individuals with ASC have significantly better visual acuity (20:7) compared with control subjects (20:13)-acuity so superior that it lies in the region reported for birds of prey.
The results of this study suggest that inclusion of sensory hypersensitivity in the diagnostic criteria for ASC may be warranted and that basic standardized tests of sensory thresholds may inform causal theories of ASC.

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    • "These abnormalities also extend to other sensory modalities in that children with ASD may show overresponsivity to unpleasant auditory input, distractibility by background noise, and/or unawareness or slow responses to familiar auditory input[38,39]. Visual difficulties also include both hyper-and hypo-responsiveness[40,41]. One plausible theory might be that children with ASD tend to over-focus their attention on details, which results in the superior processing of complex stimuli, whether auditory or visual. "
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