Expressive Suppression of Emotions in Bulimia Nervosa: An Electroencephalography Study

Objective

Previous research has found dysfunctional emotion regulation in bulimia nervosa (BN), including self-reported greater habitual use of maladaptive strategies such as suppression than in healthy individuals. However, there is no evidence on the performance in the implementation of expressive suppression in BN. The aim of this study was to investigate brain activity (in terms of ERP) and self-reported ratings associated with expressive suppression of emotions elicited by positive and negative stimuli in women with BN.

Method

Event-related potentials (ERP) were recorded from 23 female individuals with BN and 26 matched healthy controls. Participants were shown emotional pictures under two conditions: using facial suppression or attentively viewing. High-density EEG was used to characterize the time course of emotion regulation.

Results

ERP amplitudes varied significantly with valence, with positive (vs. neutral and negative) pictures eliciting larger ERP amplitudes. However, no significant differences in ERP were observed between the groups or conditions. The BN group reported lower self-efficacy in implementing suppression compared to the control group, the latter with a positive correlation between the perceived self-efficacy and the change in emotional arousal between conditions.

Discussion

Our findings suggest that individuals with BN might have difficulties in monitoring the emotion regulation process compared to healthy individuals. This suggests that other processes (e.g., metacognitive difficulties, self-esteem) rather than a failure to implement suppression, might underlie these results. However, further research is needed to validate this interpretation. Implications and directions for future research are discussed.