Neural Correlates of Alexithymia in Response to Emotional Stimuli : A Study of Anorexia Nervosa Patients

Individuals with alexithymia are typically unable to identify, understand, or describe their own emotions. Patients with anorexia nervosa (AN) have been shown to have high levels of alexithymia, and the latter trait may play an important role over the course of AN. However, relatively little is known about the underlying neurobiological relationships between alexithymia and AN. The aim of this study was to investigate the relationship between alexithymia level and brain activation in patients with AN. Thirty female patients participated in this study. Alexithymia was measured using the 20-item Toronto Alexithymia Scale. Functional magnetic resonance imaging was used to identify the brain regions that display abnormal hemodynamic activity while patients with AN were engaged in an emotional decisionmaking task. There was significant activation in the amygdala during the task, but not in the posterior and anterior cingulate cortices (PCC, ACC). However, PCC and ACC activation did vary as a function of alexithymia level. These results suggest that alexithymia in AN patients is associated with a deficit in the cognitive evaluation of negative emotions concerning body image. Alexithymia might play a crucial role in the emotional processing impairments that are often observed in AN patients, and this trait might ultimately help to better account for the psychopathological mechanism that underlies AN.