Pupil psychosensory reflex in response to own and standardised silhouettes in patients with anorexia nervosa.

OBJECTIVE: This study aimed to assess the physiological response of patients with anorexia nervosa (AN) to different types of silhouettes using pupillometry. METHODS: We measured the pupil psychosensory reflex (PSR) of 42 patients with AN and 35 healthy controls in response to standardised body silhouettes and to pictures of their own silhouettes digitally modified to represent different body mass indices (BMI). Perceptual distortion and body dissatisfaction were assessed using Anamorphic Micro Software©. Twenty-three of the recruited patients were tested up to four times during an inpatient treatment programme to assess the impact of weight gain. RESULTS: PSR correlated with the subjective rating of emotional arousal in controls but not in patients. Own silhouettes and standardised silhouettes triggered a different pupil response both in patients with AN and in controls. With pictures of their own silhouettes, pupil response to underweight stimuli differed from pupil response to normal weight or overweight stimuli in both groups. Weight gain was associated with an increase in PSR, an improvement of ideal BMI and a decrease of body dissatisfaction, but no change in perceptual distortion. CONCLUSION: Our findings support the idea that pupillometry could be a useful tool to assess the physiological state of patients with AN.

Physical exercise-related endophenotypes in anorexia nervosa.

BACKGROUND: The persistence of physical exercise in anorexia nervosa (AN) despite underweight and its maintaining factors are poorly understood. The aim of this study was to explore the attitudes toward physical exercise and its effects on emotions, cognitive functioning, and body image perception in patients with AN, and to search for exercise-related endophenotypes of the pathology. METHODS: Physical exercise dependence, quantity, and dysregulation were assessed by the Exercise Dependence Scale (EDS), the Godin Leisure Time Exercise Questionnaire (GLTEQ) and a standardized effort test in 88 patients with AN, 30 unaffected relatives and 89 healthy controls. Changes in positive and negative affect, cognitive rigidity, and body image distortion were measured before and after the effort test in the three groups. RESULTS: Patients with AN had higher scores on the EDS and the GLTEQ and used more effort in the standardized effort test. These three measures of physical exercise correlated with negative emotions at baseline. After the effort test, patients with AN had marked emotional improvement, a moderate increase in body image distortion and a small increase in cognitive rigidity compared to HC. Unaffected relatives also had a significant postexercise increase of positive emotion. DISCUSSION: The mood-related drive for physical exercise has the characteristics of an endophenotype of the disorder. Excessive and driven physical exercise may be state-associated features of AN, driven by the positive effect on emotional wellbeing.