Hunger Does Not Motivate Reward in Women Remitted from Anorexia Nervosa

Abstract

Background Hunger enhances sensitivity to reward, yet individuals with anorexia nervosa (AN) are not motivated to eat when starved. This study examined whether diminished response to reward could underlie food restriction in AN by investigating brain response to rewards during hunger and satiated states. Methods Using a delay discounting monetary decision task known to discriminate brain regions contributing to processing of immediate rewards and cognitive control important for decision making regarding future rewards, we compared 23 adults remitted from AN (to reduce the confounding effects of starvation [RAN]) to 17 healthy women (CW). Monetary rewards were used because the rewarding value of food may be confounded by anxiety in AN. Results Interactions of group (RAN, CW) × visit (hunger, satiety) revealed that, for CW, hunger significantly increased activation in reward salience circuitry (ventral striatum, dorsal caudate, anterior cingulate cortex) during processing of immediate reward, whereas satiety increased activation in cognitive control circuitry (ventrolateral prefrontal cortex, insula) during decision-making. In contrast, brain response in reward and cognitive neurocircuitry did not differ during hunger and satiety in RAN. A main effect of group revealed elevated response in the middle frontal gyrus for RAN. Conclusions RAN failed to increase activation of reward valuation circuitry when hungry and showed elevated response in cognitive control circuitry independent of metabolic state. Decreased sensitivity to hunger’s motivational drive may explain AN individuals’ ability to restrict food when emaciated. Moreover, difficulties in valuating emotional salience may contribute to inabilities to appreciate the risks inherent in this deadly disorder.

Altered interoceptive activation before, during, and after aversive breathing load in women remitted from anorexia nervosa

“…The RAN and CW groups did not differ in age (RAN mean = 26.5; CW mean = 28.3; p = 0.449), body mass index (RAN mean = 21.6; CW mean = 22.0; p = 0.568), or years of education (RAN mean = 15.9; CW mean = 15.3; p = 0.294; Table S1). Consistent with prior findings (e.g., Wierenga et al 2015), past mood and anxiety disorders were more common in the RAN group, and available data suggested that compared with controls, the RAN group reported higher, but non-clinically significant, levels of depressive symptoms, trait anxiety, and harm avoidance (Table S2). …”

On Weight and Waiting: Delay Discounting in Anorexia Nervosa Pretreatment and Posttreatment

“…These cognitive processes may be necessary in AN for making consistent healthy choices. Individuals with long-term remission of AN showed no behavioral difference from HC in a recent delay discounting study(43), suggesting that normalized discount rates persist once weight is restored.…”

Dimensions of emotion dysregulation in anorexia nervosa and bulimia nervosa: A conceptual review of the empirical literature

“…A growing number of neuroimaging studies have identified alterations in neurobiological functioning in relation to emotional, inhibitory, reward, and interoceptive processes in AN and BN. For example, studies in individuals recovered from AN and BN have revealed abnormal responses to monetary choices in reward and emotional salience circuitry (e.g., anterior ventral striatum), consistent with a shared trait for emotion dysregulation (e.g., Wagner et al, 2007; Wagner, 2010; Wierenga et al, 2015). Moreover, recent studies have revealed abnormal functioning in neurocircuitry underlying executive processes in AN and BN (e.g., Lock et al, 2011; Marsh et al, 2009, 2011; Wagner et al, 2007; Zastrow et al, 2009), which is relevant to dysregulated behaviors in BN and overregulated behaviors in AN, particularly ANr.…”