Voluntary emotion regulation in anorexia nervosa: A preliminary emotion-modulated startle investigation

Facial EMG startle response and self-report reactions after exposure to severely underweight and severely obese body images in individuals with disordered eating: An examination of motivational responses

Examining appetitive and aversive responses toward body image stimuli of those with disordered eating may illuminate motivational systems unique to eating pathology. The current study extended previous literature by examining self-report and startle responses to a range of body sizes. In this cross-sectional design, female, adult participants (n = 45) were sorted into disordered eating (DE; n = 22) and healthy control (HC; n = 23) groups based on Eating Disorder Examination Questionnaire global scores that were one standard deviation above or below normative values. Participants viewed eight computer-generated female body pictures from each group: severely underweight (BMI < 16.0), average (BMI 18.5-24.99), and severely obese (BMI > 40.0). Startle responses and self-reported valence and anxiety scores were collected to assess implicit and explicit reactions. 2 × 3 ANCOVA/ANOVAs were used to examine startle responses and self-report differences between groups, in response to image types. Results indicated startle responses did not differ between groups. There was a significant main effect for body picture type (p < .001), after controlling for psychotropic medication. Startle responses were higher for severely underweight body images compared to severely obese body images, although non-significant at post-hoc. The DE group reported higher levels of anxiety and sadness when viewing body images compared to the HC group. Average bodies were rated as less anxiety provoking and more positive than severely underweight and obese bodies. Group differences in anxiety and valence scores could be due to more maladaptive cognitions related to fear of weight gain among people with disordered eating.

Difficulties with positive emotion regulation in anorexia nervosa

Individuals with anorexia nervosa (AN) have well-documented difficulties regulating negative emotions, but less is known about positive emotion regulation in this population. To address this gap, we compared responses on the Difficulties in Emotion Regulation Scale-Positive questionnaire and the traditional DERS questionnaire (measuring negative affect dysregulation) between females with AN (n = 30) and demographically-matched controls without an eating disorder history (NC; n = 30) and examined relations between positive emotion regulation and clinical symptoms. Results indicated that individuals with AN demonstrated greater difficulty regulating negative (p < 0.001, d = 2.75) and positive (p < 0.001, d = 1.08) emotions compared to NC participants. Specifically, the AN group reported heightened positive emotion nonacceptance (p = 0.004, d = 0.78) and impulsivity (p = 0.003, d = 0.81). Greater positive emotion nonacceptance was associated with higher anxiety (p = 0.015) and depression (p = 0.022) among individuals with AN. Unexpectedly, more positive emotion impulsivity was associated with less restrictive eating in AN (p < 0.001). Findings were largely maintained even after controlling for negative emotion dysregulation and psychotropic medication use. The results suggest that reducing shame related to positive emotions could improve mood in AN; alternatively, relinquishing control when experiencing positive emotion could reduce restriction. More research is warranted on positive emotion regulation as a treatment target for AN.

Implicit and explicit motivational responses to high- and low-calorie food in women with disordered eating

Eating disorders and their symptoms are thought to be associated with altered motivational responding to food. Binge eating may relate to increased reward reactivity, restrictive eating may be associated with increased threat and/or decreased reward reactivity, and the combination of these symptoms within an individual may be linked to motivational conflict to food. Using both implicit (i.e., physiological) and explicit (i.e., self-reported) measures, we tested these hypotheses in 88 women with binge eating only, restrictive eating only, both binge eating and restrictive eating, or no eating pathology. Participants viewed and rated high-calorie food, low-calorie food, and emotional images while startle eye blink and postauricular reflexes were measured. Arousal and craving, but not valence, ratings were significantly greater for high- than low-calorie food. Startle blink reflexes during all food images were significantly lower than during neutral images, whereas only high-calorie foods related to greater postauricular reactivity than neutral images. Eating pathology group did not predict implicit and explicit motivational reactions to food. Exploratory dimensional analyses revealed that rating low-calorie foods as lower on craving predicted endorsement of restrictive eating, while rating low-calorie foods as lower on valence and arousal, and experiencing lower postauricular reactivity to high-calorie foods minus neutral images, predicted greater frequency of restrictive eating episodes. Decreased implicit and explicit appetitive motivation to high- and low-calorie food may relate to the presence and frequency of restrictive eating. Future longitudinal research should investigate whether decreased appetitive responding to food is a risk factor for, versus consequence of, restrictive eating.

Neural Processing of Food and Erotic Cues in Bulimia Nervosa

OBJECTIVE

Event-related brain potential (ERP) studies have shown that bulimia nervosa (BN) is associated with facilitated processing of disorder-specific stimuli, visible in altered early components during presentation of food cues and bodies varying in size. Less is known about BN and late ERPs, typically less influenced by perceptual features and regarded as more reliable indices of motivational relevance. The purpose of this study was to use the late positive potential (LPP) to investigate the motivational significance of BN-relevant stimuli.

METHODS

Highly salient stimuli, such as pictures of personal binge foods and images that are pleasant, neutral, and unpleasant (e.g., human attacks) were presented to 24 women with bulimia and 24 healthy women (19.7 ± 2.1 and 20.5 ± 2.6 years, respectively). Pictures of erotic couples, previously shown to prompt the greatest appetitive reactions in healthy women, were used as pleasant cues. Based on BN aversion to body cues, we hypothesized that the motivational significance of erotic cues could be increased in bulimic women.

RESULTS

Consistent with the literature, the LPP was modulated by the salience of the pictures (F(2.8,130.7) = 24.6, p < .001). An additional interaction with diagnostic group (F(2.8,130.7) = 2.8, p = .047) indicated that bulimic women showed a larger LPP than healthy controls during pictures displaying binge foods (p = .037) and erotic couples (p = .031).

CONCLUSIONS

The findings provide objective evidence that BN is characterized by dysregulated emotional processing that is not limited to food cues. The implications are discussed within a transdiagnostic perspective on food-related disorders.

Blunted emotion-modulated startle reflex in anorexia nervosa

OBJECTIVE

Patients with anorexia nervosa (AN) often show difficulties in the perception, expression, and regulation of emotions and a strong avoidance of aversive feelings. According to psychobiological models, dietary restraint and accompanying weight loss may serve as a maladaptive mechanism of emotion regulation by attenuating aversive emotional states in AN, thereby contributing to the maintenance of the disorder.

METHOD

Twenty-seven women with AN and 26 age-matched healthy women were shown short film-clips to elicit fear, sadness, amusement, and neutral emotional states. Eyeblink startle response was measured by electromyography in reaction to startle-eliciting acoustic stimuli presented 12 times binaurally during each film-clip.

RESULTS

As compared to healthy controls, patients with AN showed a blunted startle response to the fear- but not to the sadness-eliciting stimulus.

DISCUSSION

The findings support the assumption that underweight is associated with attenuated emotional reactivity to fear-eliciting material in AN. This is in line with the hypothesis that starvation and low body weight constitute a maladaptive mechanism of emotion regulation in AN, contributing to the maintenance of the disorder.

What can food-image tasks teach us about anorexia nervosa? A systematic review

A salient feature of anorexia nervosa (AN) is the persistent and severe restriction of food, such that dietary intake is inadequate to maintain a healthy body weight. Experimental tasks and paradigms have used illness-relevant stimuli, namely food images, to study the eating-specific neurocognitive mechanisms that promote food avoidance. This systematic review, completed in accordance with PRISMA guidelines, identified and critically evaluated paradigms involving images of food that have been used to study AN. There were 50 eligible studies, published before March 10th 2018, identified from Medline and PsychINFO searches, and reference screening. Studies using food image-based paradigms were categorised into three methodologic approaches: neuropsychology, neurophysiology, and functional magnetic resonance imaging (fMRI). Paradigms were reviewed with a focus on how well they address phenomena central to AN. Across tasks, differences between individuals with AN and healthy peers have been identified, with the most consistent findings in the area of reward processing. Measuring task performance alongside actual eating behaviour, and using experimental manipulations to probe causality, may advance understanding of the mechanisms of illness in AN.

Emotion dysregulation across the spectrum of pathological eating: Comparisons among women with binge eating, overeating, and loss of control eating

Emotion regulation difficulties influence the etiology and maintenance of binge eating and eating disorders, but differential associations between emotion dysregulation and objective binge eating (OBE) components have not been examined. We compared emotion dysregulation dimensions in women with OBEs (n = 27), overeating only (n = 25), loss of control (LOC) only (n = 32), or no pathological eating (n = 137). Women with OBEs had significantly more difficulty with overall emotion dysregulation, access to strategies, and impulse control when upset than other groups. Women with OBEs and women with overeating did not differ on poor emotional clarity, whereas women with OBEs and women with LOC did not differ on non-acceptance of emotions. The combination of overeating and LOC eating is associated with the greatest emotion dysregulation, but certain emotion regulation facets may differentially relate to overeating and LOC. Identifying emotion-related treatment targets for core eating disorder symptoms is important.

Processing and regulation of negative emotions in anorexia nervosa: An fMRI study

Theoretical models and recent advances in the treatment of anorexia nervosa (AN) have increasingly focused on the role of alterations in the processing and regulation of emotions. To date, however, our understanding of these changes is still limited and reports of emotional dysregulation in AN have been based largely on self-report data, and there is a relative lack of objective experimental evidence or neurobiological data. The current functional magnetic resonance imaging (fMRI) study investigated the hemodynamic correlates of passive viewing and voluntary downregulation of negative emotions by means of the reappraisal strategy detachment in AN patients. Detachment is regarded as adaptive regulation strategy associated with a reduction in emotion-related amygdala activity and increased recruitment of prefrontal brain regions associated with cognitive control processes. Emotion regulation efficacy was assessed via behavioral arousal ratings and fMRI activation elicited by an established experimental paradigm including negative images. Participants were instructed to either simply view emotional pictures or detach themselves from feelings triggered by the stimuli. The sample consisted of 36 predominantly adolescent female AN patients and a pairwise age-matched healthy control group. Behavioral and neuroimaging data analyses indicated a reduction of arousal and amygdala activity during the regulation condition for both patients and controls. However, compared with controls, individuals with AN showed increased activation in the amygdala as well as in the right dorsolateral prefrontal cortex (dlPFC) during the passive viewing of aversive compared with neutral pictures. These results extend previous findings indicative of altered processing of salient emotional stimuli in AN, but do not point to a general deficit in the voluntary regulation of negative emotions. Increased dlPFC activation in AN during passive viewing of negative stimuli is in line with the hypothesis that the disorder may be characterized by excessive self-control. Taken together, the data seem to suggest that reappraisal via detachment may be an effective strategy to reduce negative arousal for individuals with AN.