Stress and eating disorder behavior in anorexia nervosa as a function of menstrual cycle status.

OBJECTIVE: Fluctuations in ovarian hormones during the menstrual cycle and psychosocial stress contribute to eating disorder (ED) behavior. METHOD: Using ecological momentary assessment techniques, this study examined relationships between stress and binge eating, self-induced vomiting, and dietary restriction based on menstrual cycle status in anorexia nervosa (AN). One hundred nine females with full and subthreshold AN (17-45 years old) recorded ED behavior and stress ratings over 2 weeks. Using hierarchical linear modeling, individuals with eumenorrhea and those with amenorrhea or oligomenorrhea were compared. RESULTS: Following episodes of meal skipping, momentary stress decreased in individuals with normal menstrual cycles and increased in those with irregular menstrual cycles. DISCUSSION: Results suggest that changes in stress severity in response to food restriction may differ based on ovarian hormonal status and may be a mechanism by which AN is maintained in individuals without menstrual disturbance.

Heightened fear of uncertainty in anorexia and bulimia nervosa.

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 with 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. DISCUSSION: Elevated IU 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.

Altered implicit category learning in anorexia nervosa.

OBJECTIVE: Recent research has identified specific cognitive deficits in patients with anorexia nervosa (AN), including impairment in executive functioning and attention. Another such cognitive process, implicit category learning has been less studied in AN. This study examined whether implicit category learning is impaired in AN. METHOD: Twenty-one women diagnosed with AN and 19 control women (CW) were administered an implicit category learning task in which they were asked to categorize simple perceptual stimuli (Gabor patches) into one of two categories. Category membership was based on a linear integration (i.e., an implicit task) of two stimulus dimensions (orientation and spatial frequency of the stimulus). RESULTS: AN individuals were less accurate on implicit category learning relative to age-matched CW. Model-based analyses indicated that, even when AN individuals used the appropriate (i.e., implicit) strategy they were still impaired relative to CW who also used the same strategy. In addition, task performance in AN patients was worse the higher they were in self-reported novelty seeking and the lower they were in sensitivity to punishment. CONCLUSIONS: These results indicate that AN patients have implicit category learning deficits, and given this type of learning is thought to be mediated by striatal dopamine pathways, AN patients may have deficits in these neural systems. The finding of significant correlations with novelty seeking and sensitivity to punishment suggests that feedback sensitivity is related to implicit learning in AN.

Altered fimbria-fornix white matter integrity in anorexia nervosa predicts harm avoidance.

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 white matter (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 fimbria-fornix and the fronto-occipital fasciculus, as well as the posterior cingulum WM. In the AN group, Harm Avoidance was predicted by FA in the left and right fimbria-fornix. 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.

Heightened sensitivity to reward and punishment in anorexia nervosa.

OBJECTIVE: The objective of this study is to test whether females 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 females completed the study: 33 control females (CFs, mean age 19.7 years) and 31 females with AN (mean age 19.6 years). Participants completed diagnostic exams, questionnaires for eating disorder severity and personality, and the Sensitivity to Punishment/Sensitivity to Reward Questionnaire (SPSRQ). RESULTS: Females with AN scored higher than CFs on SPSRQ sensitivity to punishment (p < 0.00001) and sensitivity to reward (p = 0.005). Females with AN without anxiety or depression continued to have increased SPSRQ scores compared to CFs. DISCUSSION: This is the first study comparing the SPSRQ in females with AN and CFs. Results suggest that reward and punishment sensitivity are increased in females with AN and could be potential trait markers. It is possible that harm-avoidant, anxious behaviors in females with AN are related to this heightened sensitivity.

Body-image perception and dissatisfaction throughout phases of the female menstrual cycle.

This pilot study investigated the association between the menstrual cycle and participants' body-size perception, judgments of ideal body size, detection of changes in body size, and body dissatisfaction. Thirty participants (M age=23.3 yr., SD=3.9), who did not have eating disorders, viewed digital images of their bodies. Judgments on all tasks were made during premenstrual, intermenstrual, and menstrual phases of the menstrual cycle. Participants expressed a desire for a smaller ideal body size for themselves in all three phases. Body dissatisfaction was significantly greater during the premenstrual and menstrual phases. The menstrual cycle was not associated with significant changes in body-size perception, ideal size judgments, or detection of changes in body size.

Development and validation of a new figural drawing scale for body-image assessment: the BIAS-BD.

This study describes the development and validation of a new and improved body-image assessment tool, the BIAS-BD, based on known body dimensions. The scale's construction consisted of 17 male and 17 female contour-line drawings that used known anthropometric body dimensions of shoulder, chest, waist, hip breadth, thigh breadth, and upper leg breadth. The figural drawings correspond to a series of body weights ranging from 60% below the known average to 140% above average. Differences between figural drawings represented a 5% change in body weight. Participants were 207 undergraduates, including 66 men and 141 women, who selected drawings that reflected their perceived size and their ideal size. Retesting occurred after a 2-week interval and resulted in test-retest reliability values of r=.86 for actual perceived size, r=.72 for ideal size, and r=.76 for body dissatisfaction (p<.005). There were no significant differences in reliability values between genders. Mean differences in perceived size, ideal size, and body dissatisfaction between the two test administrations were small. Concurrent validity, measured as the correspondence between perceived and reported size, was r=.76 (p<.005). Participants slightly overestimated their perceived body size, with women overestimating significantly more. Unlike existing scales, the present scale uses figural drawings based on known body dimensions and has better reliability and validity. It avoids several problems inherent in existing scales, including scale coarseness, the presence of ethnic facial and body features, and the lack of documented reliability and validity values.