Mental imagery scanning in autism spectrum disorder

Navigational impairments have previously been reported in autism spectrum disorder (ASD). The present study examined the ability of individuals with ASD to generate and scan their mental image of a previously viewed map. Twenty-one ASD adults and 20 age- and IQ-matched comparison adults memorised a map of a fictitious island containing a number of landmarks. They then mentally imagined the map and were timed as they imagined a character walking between the various landmarks. Consistent with previous mental imagery research with typical individuals, there was a linear relationship between the time that participants took to mentally scan between the landmarks and the actual distance between the landmarks on the picture, and this was the case for both typical and ASD participants. ASD and comparison participants' mental image scanning times were both also influenced by misleading signposts in the picture that indicated different distances between landmarks, thus providing evidence that their mental images were penetrable by top-down information. Although ASD and comparison participants showed very similar mental imagery scanning performance, verbal IQ and working memory were significantly and positively associated with image scanning performance for the ASD, but not the comparison group. This finding furthers the notion of a compensatory reliance on different strategies in ASD to achieve similar surface performance to individuals from the general population. Findings have practical implications for supporting navigation strategies in ASD. (C) 2014 The Authors. Published by Elsevier Ltd.