Visual perspective-taking and schizotypy: evidence for a simulation-based account of mentalizing in normal adults.

Modular theory-of-mind accounts attribute poor mentalizing to disruption of a cognitive module dedicated to computing higher-order representations of primary representations (metarepresentations). Since metarepresentational capacity is needed to mentalize about other people's beliefs but is not needed to judge visual perspectives (which can be done by mentally rotating primary representations of seen objects), this view predicts that visual perspective-taking will be intact in individuals with selective mentalizing impairments. Counter to that prediction, this study found evidence of disturbed visual perspective-taking in normal adults who score higher on the personality variable of schizotypy and who are known to be relatively poor mentalizers (despite intact ability to inhibit salient inappropriate information in order to reason consequentially on the basis of hypothetical states, other than mental states). Whereas high-schizotypal adults and low-schizotypal adults did not differ in their ability to judge item questions (asking the relative location of array features), high-schizotypal adults performed more poorly than low-schizotypal adults in judging appearance questions (asking how an array would appear from another perspective) under viewer-rotation instructions (asking subjects to imagine moving themselves relative to a fixed array) and performed better than low-schizotypal adults in judging appearance questions under array-rotation instructions (asking subjects to imagine rotating an array relative to their own fixed viewer position). Based on these and other findings we conclude that poor mentalizing in normal adults is better understood as an impairment of perspective-taking (visual and/or cognitive) and introduce the concept of allocentric simulation to explain the functional basis of this perspective-taking impairment.