Mirror exposure in women with bulimic symptoms: how do thoughts and emotions change in body image treatment?

Mirror exposure is an efficient treatment for body image problems in eating disorders. Although habituation processes and cognitive changes are postulated to be underlying mechanisms, evidence is scarce, especially during repeated mirror exposure treatment. Fourteen participants with eating disorders not otherwise specified (EDNOS) and five with bulimia nervosa (BN) composed the bulimic group (BG), and 19 healthy women without any mental disorder composed the healthy controls group (HC). The participants were treated by four standardized mirror exposure sessions. Subjective distress was assessed five times during each session. Both negative and positive emotions and negative thoughts were assessed after each session. The patients in the BG reported significantly higher levels of negative emotions and cognitions than did those in the HC in all measures and across all sessions. In both groups, subjective distress increased significantly within each session and decreased toward the end of each session. Only in the subjects of the BG group did both distress and negative thoughts and emotions decrease significantly from session to session, whereas positive emotions increased. The patterns of change differed between the BG and the HC, suggesting that habituation between sessions occurred only in the BG. Our findings suggest that the additional underlying cognitive-affective processes merit further investigation.