title: Ensemble perception of color in autistic adults.
abstract: Dominant accounts of visual processing in autism posit that autistic individuals have an enhanced access to details of scenes [e.g., weak central coherence] which is reflected in a general bias toward local processing. Furthermore, the attenuated priors account of autism predicts that the updating and use of summary representations is reduced in autism. Ensemble perception describes the extraction of global summary statistics of a visual feature from a heterogeneous set (e.g., of faces, sizes, colors), often in the absence of local item representation. The present study investigated ensemble perception in autistic adults using a rapidly presented (500 msec) ensemble of four, eight, or sixteen elements representing four different colors. We predicted that autistic individuals would be less accurate when averaging the ensembles, but more accurate in recognizing individual ensemble colors. The results were consistent with the predictions. Averaging was impaired in autism, but only when ensembles contained four elements. Ensembles of eight or sixteen elements were averaged equally accurately across groups. The autistic group also showed a corresponding advantage in rejecting colors that were not originally seen in the ensemble. The results demonstrate the local processing bias in autism, but also suggest that the global perceptual averaging mechanism may be compromised under some conditions. The theoretical implications of the findings and future avenues for research on summary statistics in autism are discussed. Autism Res 2017, 10: 839-851. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.
authors.affiliation: Sussex Colour Group, School of Psychology, Pevensey 1, North-South Road, University of Sussex, Brighton, BN1 9QH, UK.
authors.forename: John
authors.initials: J
authors.lastname: Maule
authors.affiliation: Sussex Colour Group, School of Psychology, Pevensey 1, North-South Road, University of Sussex, Brighton, BN1 9QH, UK.
authors.forename: Kirstie
authors.initials: K
authors.lastname: Stanworth
authors.affiliation: UCL Institute of Education, University College London, 55-59 Gordon Square, WC1H 0NU, London.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Pellicano
authors.affiliation: Sussex Colour Group, School of Psychology, Pevensey 1, North-South Road, University of Sussex, Brighton, BN1 9QH, UK.
authors.forename: Anna
authors.initials: A
authors.lastname: Franklin
mesh_terms: D000328:Adult; D001321:Autistic Disorder / Q000503:physiopathology*; D003118:Color Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D055815:Young Adult
keywords: autism; color; ensemble perception; global processing; priors; visual perception