Rules versus prototype matching: strategies of perception of emotional facial expressions in the autism spectrum.

When perceiving emotional facial expressions, people with autistic spectrum disorders (ASD) appear to focus on individual facial features rather than configurations. This paper tests whether individuals with ASD use these features in a rule-based strategy of emotional perception, rather than a typical, template-based strategy by considering outcome implications of these strategies. Rule-based strategies are more tolerant of extreme stimuli than are template-based ones. Tolerance for exaggerated emotional facial expressions in individuals with ASD compared to IQ and education matched controls was tested in a forced-choice paradigm. For five of six emotions, those with ASD were more likely to accept the most exaggerated images as most realistic. People with ASD appear to rely more heavily on a rule-based strategy than a template-based strategy in perceiving emotional facial expressions.