The light-from-above prior is intact in autistic children

Croydon, Abigail, Karaminis, Themis, Neil, Louise, Burr, David and Pellicano, Elizabeth (2017) The light-from-above prior is intact in autistic children. Journal of Experimental Child Psychology, 161. pp. 113-125. ISSN 0022-0965 DOI

TK_pdf5.pdf - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (759kB) | Preview


Sensory information is inherently ambiguous. The brain disambiguates this information by anticipating or predicting the sensory environment based on prior knowledge. Pellicano and Burr (2012) proposed that this process may be atypical in autism and that internal assumptions, or ‘‘priors,” may be underweighted or less used than in typical individuals. A robust internal assumption used by adults is the ‘‘light-from-above” prior, a bias to interpret ambiguous shading patterns as if formed by a light source located above (and slightly to the left) of the scene. We investigated whether autistic children (n = 18) use this prior to the same degree as typical children of similar age and intellectual ability (n = 18). Children were asked to judge the shape (concave or convex) of a shaded hexagon stimulus presented in 24 rotations. We estimated the relation between the proportion of convex judgments and stimulus orientation for each child and calculated the light source location most consistent with those judgments. Children behaved similarly to adults in this task, preferring to assume that the light source was from above left, when other interpretations were compatible with the shading evidence. Autistic and typical children used prior assumptions to the same extent to make sense of shading patterns. Future research should examine whether this prior is as adaptable (i.e., modifiable with training) in autistic children as it is in typical adults.

Item Type: Article
Uncontrolled Keywords: PerceptionAutismBayesian priorsLight-from-aboveDevelopmentBias
Subjects: B Philosophy. Psychology. Religion > BF Psychology
Divisions: Psychology
Date Deposited: 06 Mar 2018 15:11

Archive staff only

Item control page Item control page