What the Eye Sees, the Mind Rejects: Implicit Visual Processing of Food Images in Anorexia Nervosa.

Abstract

Objective: This study aims to explore the role of implicit visual processing in reinforcing maladaptive eating behaviours in Anorexia Nervosa-restricting subtype (AN-R), focussing on how high- and low-calorie food stimuli are processed at different stages.

Method: Thirty-two AN-R females and 36 healthy controls participated. Using a combination of novel paradigms in the field, the study employed: Breaking Continuous Flash Suppression (bCFS) for unconscious detection, Binocular Rivalry (BR) for perceptual dominance, and the Food Preference Approach-Avoidance Task (FP-AAT) for subconscious food associations.

Results: AN-R individuals exhibited prolonged perceptual dominance for high-calorie foods but simultaneously displayed stronger implicit avoidance tendencies towards these foods. Notably, the perceptual advantage correlated with heightened interoceptive awareness, while avoidance was linked to body dissatisfaction and difficulty tolerating bodily sensations. Conversely, healthy females showed the opposite pattern, implicitly approaching high-calorie foods while avoiding low-calorie foods, suggesting a more adaptive integration of food-related cues.

Conclusions: This study provides novel insights into the complex role of high-calorie foods in AN, highlighting whether and how different aspects of implicit visual processing influence eating behaviours, and underscoring the need for targeted interventions incorporating implicit cognitive mechanisms to address visual processing biases and support AN recovery.