The left amygdala: A shared substrate of alexithymia and empathy.

Alexithymia, a deficit in emotional self-awareness, and deficits in empathy, which encompasses the awareness of other's emotions, are related constructs that are both associated with a range of psychopathological disorders. Neuroimaging studies suggest that there is overlap between the neural bases of alexithymia and empathy, but no systematic comparison has been conducted so far. The aim of this structural magnetic resonance imaging study was to disentangle the overlap and differences between the morphological profiles of the cognitive and affective dimensions of alexithymia and empathy, and to find out to what extent these differ between women and men.

Neuroanatomical profiles of alexithymia dimensions and subtypes.

Alexithymia, a major risk factor for a range of psychiatric and neurological disorders, has been recognized to comprise two dimensions, a cognitive dimension (difficulties identifying, analyzing, and verbalizing feelings) and an affective one (difficulties emotionalizing and fantasizing). Based on these dimensions, the existence of four distinct alexithymia subtypes has been proposed, but never empirically tested. In this study, 125 participants were assigned to four groups corresponding to the proposed alexithymia subtypes: Type I (impairment on both dimensions), Type II (impairment on the cognitive, but not the affective dimension), Type III (impairment on the affective, but not the cognitive dimension), and Lexithymics (no impairment on either dimension).

Dissociable morphometric profiles of the affective and cognitive dimensions of alexithymia.

Alexithymia ("no words for feelings") is a psychological construct that can be divided in a cognitive and affective dimension. The cognitive dimension reflects the ability to identify, verbalize and analyze feelings, whereas the affective dimension reflects the degree to which individuals get aroused by emotional stimuli and their ability to fantasize. These two alexithymia dimensions may differentially put individuals at risk to develop psychopathology.

Distinct associations of insula and cingulate volume with the cognitive and affective dimensions of alexithymia.

Alexithymia ("no words for feelings") is a major risk factor for psychosomatic and psychiatric conditions characterized by affect dysregulation. The alexithymia personality construct comprises an affective dimension, the level of subjective emotional experience (emotionalizing and fantasizing), and a cognitive dimension, referring to the cognitive control of emotions (identifying, analyzing, and verbalizing feelings). These two dimensions may differentially put individuals at risk for psychopathology, but their specific neural bases have rarely been investigated.

Blunted feelings: alexithymia is associated with a diminished neural response to speech prosody.

How we perceive emotional signals from our environment depends on our personality. Alexithymia, a personality trait characterized by difficulties in emotion regulation has been linked to aberrant brain activity for visual emotional processing. Whether alexithymia also affects the brain's perception of emotional speech prosody is currently unknown.