Children with autism are neither systematic nor optimal foragers
- aCentre for Research in Autism and Education, Department of Psychology and Human Development, Institute of Education, London WC1H 0AA, United Kingdom;
- bSchool of Psychology, University of Western Australia, Crawley, 6009, Australia;
- cSchool of Psychology, University of Nottingham, Nottingham NG7 2RD, United Kingdom;
- dSchool of Psychology, Adeilad Brigantia, Bangor University, Bangor, Gwynedd LL57 2AS, United Kingdom; and
- eDepartment of Experimental Psychology, University of Bristol, Bristol BS8 1TU, United Kingdom
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Edited by Dale Purves, Duke University Medical Center, Durham, NC, and approved November 19, 2010 (received for review September 19, 2010)

Abstract
It is well established that children with autism often show outstanding visual search skills. To date, however, no study has tested whether these skills, usually assessed on a table-top or computer, translate to more true-to-life settings. One prominent account of autism, Baron-Cohen's “systemizing” theory, gives us good reason to suspect that they should. In this study, we tested whether autistic children's exceptional skills at small-scale search extend to a large-scale environment and, in so doing, tested key claims of the systemizing account. Twenty school-age children with autism and 20 age- and ability-matched typical children took part in a large-scale search task in the “foraging room”: a purpose-built laboratory, with numerous possible search locations embedded into the floor. Children were instructed to search an array of 16 (green) locations to find the hidden (red) target as quickly as possible. The distribution of target locations was manipulated so that they appeared on one side of the midline for 80% of trials. Contrary to predictions of the systemizing account, autistic children's search behavior was much less efficient than that of typical children: they showed reduced sensitivity to the statistical properties of the search array, and furthermore, their search patterns were strikingly less optimal and less systematic. The nature of large-scale search behavior in autism cannot therefore be explained by a facility for systemizing. Rather, children with autism showed difficulties exploring and exploiting the large-scale space, which might instead be attributed to constraints (rather than benefits) in their cognitive repertoire.
Footnotes
- 1To whom correspondence should be addressed. E-mail: l.pellicano{at}ioe.ac.uk.
Author contributions: E.P., A.D.S., B.M.H., J.B, and I.D.G. designed research; E.P., A.D.S., and J.B. performed research; F.C. and I.D.G. contributed new reagents/analytic tools; E.P., A.D.S., and F.C. analyzed data; and E.P., A.D.S., F.C., B.M.H., J.B., and I.D.G. wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS direct submission.