Alexithymia, gender, and hemispheric functioning.

It has been hypothesized that alexithymia is related to an impairment of the right hemisphere or a deficiency in interhemispheric transfer. We used the Toronto Alexithymia Scale-20 (TAS-20) and the tactile finger localization task of Zeitlin et al. to test these relationships on nonclinical samples of college men and women, and also considered the role of short-term memory. Among 47 men, the TAS-20 facets of difficulty identifying feelings or difficulty describing feelings were correlated with poorer performance by the right compared with the left hemisphere in uncrossed trials and poorer interhemispheric transfer of information on crossed trials; short-term memory was not related. Thus, both hemispheric hypotheses were supported for men. However, among 58 women, alexithymia was completely unrelated to either index of hemispheric functioning; instead, poorer short-term memory (specifically digits backwards) strongly predicted poorer interhemispheric transfer. We conclude that deficiencies in right hemisphere function and interhemispheric transfer may contribute to alexithymia in men, but not in women.