Do empirically-derived personality subtypes relate to cognitive inflexibility in anorexia nervosa and bulimia nervosa?

Background: Accruing evidence suggests that personality-based approaches to eating disorder classification may offer several advantages over current diagnostic models, with prior research consistently identifying three personality-based groups characterized by either (1) high levels of impulsivity and dysregulation (termed the "undercontrolled" group), (2) high levels of rigidity and avoidance (termed the "overcontrolled" group), or (3) relatively normative levels of personality functioning (termed the "low psychopathology" group). Cognitive inflexibility (i.e., difficulty adjusting thoughts or behaviors) has theorized relevance to eating disorders. However, prior research has frequently failed to observe differences in cognitive inflexibility across eating disorder diagnostic groups. The present study aimed to identify personality-based groups in an eating disorder sample, and then to examine the relations between these groups and behavioral measures of cognitive inflexibility.

Method: 83 men and women who met DSM-5 criteria for anorexia nervosa or bulimia nervosa completed self-report questionnaires to assess trait-level approach/avoidance behaviors and impulsivity, as well as behavioral tasks assessing attentional set-shifting and reversal learning, two facets of cognitive inflexibility.

Results: Latent profile analysis of measures assessing approach/avoidance behaviors and impulsivity supported a three-class model replicating the undercontrolled, overcontrolled, and low psychopathology groups. Notably, the low psychopathology group was characterized by elevated reward responding. One-way ANOVAs indicated that the low psychopathology group demonstrated heightened perseverative errors (an indicator of impaired reversal learning) relative to the other groups. No group differences were observed for attentional set-shifting errors or probabilistic switch errors.

Discussion: Findings from the present study provide additional support for personality-based classification approaches identifying undercontrolled, overcontrolled, and low psychopathology eating disorder groups. Results also suggest that reward-related processes may contribute to disorder maintenance in the low psychopathology group, indicating potentially meaningful targets for intervention.