A cross-modal component of alexithymia and its relationship with performance in a social cognition task battery.

Background: The personality trait alexithymia describes an altered emotional awareness that is associated with a range of social impairments and constitutes a transdiagnostic risk factor for various psychopathologies. Despite the characteristic interoceptive deficits in alexithymia, it is predominantly assessed via self-reports. This can result in unreliable measurements and arguably contributes to the prevailing uncertainty regarding its components, including constricted imaginal processes and emotional reactivity.

Methods: The current study employed an interview and two validated questionnaires to derive a shared component of multi-modally assessed alexithymia in a German non-clinical sample (n = 78) via prinicipal component analysis. This component was used as a predictor for performance in four behavioural social cognition tasks. The relative importance of this predictor against related variables was assessed via dominance analysis.

Results: The identified component reflected cognitive alexithymia. Higher cognitive alexithymia scores were associated with less affective distress in an ostracizing task. Dominance analysis revealed the dominance of competing autism traits relative to cognitive alexithymia and competing predictors empathy, depression, and anxiety, in predicting affective distress.

Limitations: Emotional reactivity was only assessed via self-report and no implicit measures of alexithymia were employed. Due to the low reliability of the self-report measure, no measure of emotional reactivity could be included in the principal component analysis.

Conclusions: Our results provide compelling evidence that cognitive interoceptive deficits are at the core of alexithymia across assessment modalities. Behavioural data suggest that these deficits result in diminished emotional sensitivity to high-pressure social situations, which may cause a lack of behavioural adaptation.