The Role of Habits in Anorexia Nervosa: Where We Are and Where to Go From Here?

Abstract

Purpose of review: The persistent maladaptive eating behavior characteristic of anorexia nervosa (AN) can be understood as a learned habit. This review describes the cognitive neuroscience background and the existing data from research in AN.

Recent findings: Behavior is habitual after it is frequently repeated and becomes nearly automatic, relatively insensitive to outcome, and mediated by dorsal frontostriatal neural systems. There is evidence for such behavior in AN, in which restrictive intake has been related to dorsal frontostriatal systems. Other neural and neurocognitive data provide mixed findings, some of which suggest disturbances in habit systems in AN. There are compelling behavioral and neural data to suggest that habit systems may underlie the persistence of AN. The habit model needs further research, via more direct behavioral hypothesis testing and probes of the development of habitual behavior. Investigation of the habit-centered model of AN may open avenues for the development of novel treatments.

Keywords: Anorexia nervosa; Cognitive neuroscience; Eating disorders; Frontostriatal; Habit; Reward.

Fig. 1

a Habit-centered model of AN. Early in illness, the characteristic dieting behavior of AN involves stimulus-response-outcome learning. In this model, dieting behavior begins as a goal-directed action that is taken in response to a stimulus (e.g., mealtime) and is sensitive to outcome (i.e., reward). Repeated multiple times daily over weeks to months, the behavior gradually becomes less insensitive to outcome and occurs almost automatically (or habitually) after exposure to a food-related stimulus. b Neural representation of reward and habit circuitry. During stimulus-response-outcome learning, dieting behavior is sensitive to the receipt of reward and engages key reward-related circuits including the ventral striatum (VS) and ventromedial prefrontal cortex (vmpFC). As behavior becomes less reliant on reward and more automated, habit-associated structures are engaged, including the dorsal striatum (DS) and dorsolateral prefrontal cortex (dlPFC)