Anorexia nervosa (AN) is a severe psychiatric disorder associated with food avoidance and malnutrition. In this study, we wanted to test whether we would find brain reward alterations in AN, compared with individuals with normal or increased body weight. We studied 21 underweight, restricting-type AN (age M 22.5, SD 5.8 years), 19 obese (age M 27.1, SD 6.7 years), and 23 healthy control women (age M 24.8, SD 5.6 years), using blood oxygen level-dependent functional magnetic resonance brain imaging together with a rewardconditioning task. This paradigm involves learning the association between conditioned visual stimuli and unconditioned taste stimuli, as well as the unexpected violation of those learned associations. The task has been associated with activation of brain dopamine reward circuits, and it allows the comparison of actual brain response with expected brain activation based on established neuronal models. A group-by-task condition analysis (family-wise-error-corrected Po0.05) indicated that the orbitofrontal cortex differentiated all three groups. The dopamine model reward-learning signal distinguished groups in the anteroventral striatum, insula, and prefrontal cortex (Po0.001, 25 voxel cluster threshold), with brain responses that were greater in the AN group, but lesser in the obese group, compared with controls. These results suggest that brain reward circuits are more responsive to food stimuli in AN, but less responsive in obese women. The mechanism for this association is uncertain, but these brain reward response patterns could be biomarkers for the respective weight state.

The eating disorder anorexia nervosa (AN) is associated with high anxiety. The brain mechanisms that drive those behaviors are unknown. In this study we wanted to test whether brain WM integrity is altered in AN, and related to heightened anxiety. Sixteen adult women with AN (mean age 24±7 years) and 17 healthy control women (CW, mean age 25±4 years) underwent diffusion tensor imaging (DTI) of the brain. The DTI brain images were used to calculate the fractional anisotropy (FA) of WM tracts, which is a measure for WM integrity. AN individuals compared to CW showed clusters of significantly reduced FA (p<0.05, corrected) in the bilateral fimbriafornix, fronto-occipital fasciculus, as well as posterior cingulum WM. In the AN group, Harm Avoidance was predicted by left (F=5.8, Beta=−0.54, p<0.03) and right (F=6.0, Beta=−0.55, p<0.03) fimbria-fornix FA. Those findings were not due to WM volume deficits in AN. This study indicates that WM integrity is abnormal in AN in limbic and association pathways, which could contribute to disturbed feeding, emotion processing and body perception in AN. The prediction of Harm Avoidance in AN by fimbria-fornix WM integrity suggests that this pathway may be mechanistically involved in high anxiety in AN.

Objective-To test whether women with Anorexia Nervosa (AN) have increased sensitivity to punishing or rewarding stimuli, behaviors that could drive high self-control and anxious, avoidant behaviors.Method-Sixty-four women completed the study: 33 control women (CW, mean age 19.7 years) and 31 AN (mean age 19.6 years). Participants completed diagnostic exams, questionnaires for eating disorder severity and personality, as well as the Sensitivity to Punishment/Sensitivity to Reward Questionnaire (SPSRQ).Results-AN scored higher than CW on SPSRQ sensitivity to punishment (p<0.00001) and sensitivity to reward (p=0.005). AN women without anxiety or depression continued to have increased SPSRQ scores compared to CW.Conclusion-This is the first study comparing the SPSRQ in AN and CW. Results suggest that reward and punishment sensitivity are increased in AN and could be potential trait markers. It is possible that harm-avoidant, anxious behaviors in AN are related to this heightened sensitivity.Anorexia Nervosa (AN) is a severe, often persistent mental illness with the highest mortality rate among all the psychiatric disorders (1). AN is characterized by intense fear of gaining weight, food restriction and weight loss, body image distortion, and amenorrhea (2). Central to AN is the ego-syntonic nature of weight loss, as well as the high rate of treatment resistance and drop out (3). The underlying pathophysiology of AN is unknown.AN is frequently associated with co-morbid anxiety disorders that often predate the emergence of eating disorder (ED) pathology (4). Individuals with AN are consistently characterized as highly perfectionistic and controlling (5) and show temperament traits such as high harm avoidance (HA; shy, fearful, worrying behavior, tendency to avoid perceived punishment), and lower novelty seeking (NS; the desire to explore and approach potential rewards) (4,(6)(7)(8)(9). These characteristics raise the question whether such behaviors in AN are primary or adaptive in order to tolerate and handle the ups and downs of failures and Corresponding Author Guido K.W. Frank, MD, Assistant Professor, Departments of Psychiatry and Neuroscience, Director, Developmental Brain Research Program, University of Colorado Denver, The Children's Hospital, Gary Pavilion A036/B-130, 13123 East 16th Avenue, Aurora, CO 80045, Tel.: 720-777-1909, Guido.Frank@ucdenver.edu. NIH Public Access Author ManuscriptInt J Eat Disord. Author manuscript; available in PMC 2012 May 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript accomplishments in daily life. While speculative, AN individuals may have heightened emotional or physiological sensitivity to experiences that are associated with reward or punishment, and that the eating disorder and associated behaviors may in some way serve to mitigate these responses by the sense of control received. We hypothesized that individuals with AN might be overly sensitive to the saliency of punishing or rewarding stimuli, and they may act to minimize exposure ...

Objective-To test whether intolerance of uncertainty (IU) is related to eating disorder (ED) pathology.Method-Thirty individuals with anorexia nervosa (AN), 19 with bulimia nervosa (BN) and 28 healthy control women (CW) completed the Intolerance of Uncertainty Scale (IUS).Results-AN and BN groups showed higher IU compared to CW. In AN and BN, Harm Avoidance and Depression scores were positively correlated with IU. In AN but not BN, IU was related positively to Drive for Thinness and Body Dissatisfaction. Conclusion-ElevatedIU is associated with AN and BN. Anxious traits may be inherent in EDs and IU could be a developmental factor contributing to anxiety, mood and ED behavior in AN and BN.

Although peer influences are thought to be critically important to adolescent development, there is a paucity of research investigating the emotion socialization practices that take place between adolescents. This longitudinal study evaluated close friends' responses to negative emotion using a newly developed assessment tool of peer emotion socialization, you and your friends. Adolescent participants (N = 205) exhibiting a range of internalizing and externalizing problems between 11 and 17 years of age were assessed and re‐evaluated two years later. Participants were asked to rate the frequency with which their friends responded to them by encouraging, distracting, matching, ignoring, overtly victimizing, and/or relationally victimizing their emotions. The results indicated high levels of internal consistency and moderate levels of long‐term stability. Close friends most often responded supportively to the participants' emotional displays, but these responses differed by gender. Also, friends' emotion socialization responses were concurrently and predictively associated with participant problem status. This study contributes to a better understanding of the processes by which adolescents' emotions are socialized by their friends and has important implications for future prevention and intervention efforts.