Alexithymia: a right hemisphere dysfunction specific to recognition of certain facial expressions?

The most prominent features of alexithymic people are a demonstrated reduction in the ability to identify and to describe their own feelings. In recent years, these characteristics have been related to a functional disturbance of the right cerebral hemisphere. This should result in a number of other observable effects. The present study investigated whether high and low alexithymics from a nonclinical population differed in the degree of leftward perceptual bias on chimeric tasks. The chimeras consisted of pictures of faces made of up conjoined emotive and nonemotive halves as well as asymmetrically distributed stars. Differences between high and low alexithymics in the recognition of facial expressions of emotion of whole faces were also examined. High scorers on a test of alexithymia showed overall less leftward perceptual bias than low scores on the chimeric tasks and poorer recognition of facial expressions of whole faces. There was little evidence that the reduced left bias was specific to processing of emotional expressions only, or that differences in processing of facial expressions were emotion specific. These results are argued to support the right hemisphere dysfunction model of alexithymia.