Neural Substrates of Affective Face Recognition in Alexithymia: A Functional Magnetic Resonance Imaging Study

BACKGROUND: Alexithymia is a condition characterized by deficits in cognitive processing and the regulation of emotions. Several theories have been proposed for the underlying neurobiology, but the etiology of alexithymia remains unclear. METHODS: Using functional magnetic resonance imaging, we investigated brain activation measured on the scale of alexithymia in 38 individuals who were presented with neutral, sad, or angry affective facial stimuli. RESULTS: We found significant inverse correlations between the degree of alexithymia represented by the Korean version of the Toronto Alexithymia Scale (TAS-20K) and the intensity of the neural response to angry facial stimuli over neutral facial stimuli in the right caudate. This result was mainly due to the activations in factor 2 (difficulty describing feelings) in TAS-20K scale. CONCLUSIONS: The results suggest that functional impairments in the caudate of the fronto-striatal circuitry may play important roles in the pathophysiology of alexithymia.