Abnormal patterns of cerebral lateralisation as revealed by the Universal Chimeric Faces Task in individuals with autistic disorder.

A previous study by Workman, Chilvers, Yeomans, and Taylor (2006), using the "Universal" Chimeric Faces Task (UCFT) for six emotional expressions, demonstrated that an overall left hemispatial/right hemisphere (RH) advantage has begun to develop by the age of 7-8. Moreover, the development of this left hemispatial advantage was observed to correlate positively with the ability to read emotions in the faces of others. Adopting the UCFT, the current study compared autistic children (11-15) with unimpaired children of two age groups (5-6 and 7-8) from this previous study. The autistic children showed a left hemispatial/RH advantage only for the two emotional expressions of "happiness" and "anger". Results for the autistic children revealed a similar overall pattern of lateralisation to the 5-6-year-olds and one that is less lateralised than the pattern for the 7-8-year-olds. Autistic children appear to show a developmental deficit for left hemispatial/RH advantage for emotional expression with the exception of "happiness" and "anger." The findings are discussed in terms of role hemisphericity and an approach-avoidance model.