Experimental induction of thought-shape fusion in eating disorder patients: the role of coping strategies

Objective: The aim was to induce the thought-shape fusion (TSF) distortion experimentally, testing: a) Whether the TSF distortion could be induced by anxiety in general or if it had a specific relationship with thoughts related to the intake of fattening foods; b) Whether the TSF could be induced in non-clinical participants as well as in the eating disorder patients; c) Whether participants with more appropriate coping strategies would experience less TSF than those who showed inadequate coping strategies; and d) That TSF could have behavioural effects (e.g., neutralization of TSF and food intake) related to emotions. Methods: The sample comprised two groups (eating disorder patients and students), with 45 participants each, aged between 18 and 25 years, 92.50% and 86.7% of women in the eating disorders group and the students group respectively. The two groups underwent three experimental conditions (TSF, anxiety, and control), measuring the results with regards to the emotional and behavioural responses. Results: Participants in the TSF induction condition reported more guilt, more feelings of fatness, more likelihood of weight gain, and higher degree of moral wrongdoing compared with participants in both the anxiety and control induction conditions. The effect of the adequate coping strategies in decreasing the strength of the TSF bias was confirmed in both eating disorder patients and non-clinical participants. Discussion: The study of the TSF distortion may have relevant implications in terms of treatment and prognostic of eating disorders. This distortion may be involved in the development and maintenance of eating disorder psychopathology.