title: Enhanced integration of motion information in children with autism.
abstract: To judge the overall direction of a shoal of fish or a crowd of people, observers must integrate motion signals across space and time. The limits on our ability to pool motion have largely been established using the motion coherence paradigm, in which observers report the direction of coherently moving dots amid randomly moving noise dots. Poor performance by autistic individuals on this task has widely been interpreted as evidence of disrupted integrative processes. Critically, however, motion coherence thresholds are not necessarily limited only by pooling. They could also be limited by imprecision in estimating the direction of individual elements or by difficulties segregating signal from noise. Here, 33 children with autism 6-13 years of age and 33 age- and ability-matched typical children performed a more robust task reporting mean dot direction both in the presence and the absence of directional variability alongside a standard motion coherence task. Children with autism were just as sensitive to directional differences as typical children when all elements moved in the same direction (no variability). However, remarkably, children with autism were more sensitive to the average direction in the presence of directional variability, providing the first evidence of enhanced motion integration in autism. Despite this improved averaging ability, children with autism performed comparably to typical children in the motion coherence task, suggesting that their motion coherence thresholds may be limited by reduced segregation of signal from noise. Although potentially advantageous under some conditions, increased integration may lead to feelings of "sensory overload" in children with autism.
authors.affiliation: Centre for Research in Autism and Education, UCL Institute of Education, University College London, London WC1H 0NU, United Kingdom, Department of Experimental Psychology, University of Oxford, Oxford OX1 3UD, United Kingdom, catherine.manning@psy.ox.ac.uk.
authors.forename: Catherine
authors.identifier: http://orcid.org/0000-0001-6862-2525
authors.initials: C
authors.lastname: Manning
authors.affiliation: Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom.
authors.forename: Marc S
authors.initials: MS
authors.lastname: Tibber
authors.affiliation: Institute of Psychiatry, Psychology & Neuroscience, King's College London, London SE5 8AF.
authors.forename: Tony
authors.initials: T
authors.lastname: Charman
authors.affiliation: Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom, Department of Optometry and Vision Science, University of Auckland, Auckland 1142, New Zealand, and.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Dakin
authors.affiliation: Centre for Research in Autism and Education, UCL Institute of Education, University College London, London WC1H 0NU, United Kingdom, School of Psychology, University of Western Australia, Perth 6009, Australia.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Pellicano
mesh_terms: D000293:Adolescent; D001321:Autistic Disorder / Q000175:diagnosis* / Q000523:psychology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods*; D011597:Psychomotor Performance / Q000502:physiology*
keywords: autism; developmental disorders; motion perception