An examination of frontal asymmetry in relation to eating in the absence of hunger and loss-of-control eating.

Loss-of-control (LOC) eating involves a subjective feeling that one cannot stop eating or control one's eating. Individuals with LOC eating may exhibit strong appetitive drives and weak inhibitory control, and these two opposing motivations have been related to EEG measurements of frontal asymmetry or lateralized frontal activation. The present study investigated whether frontal asymmetry is related to hedonic hunger, LOC eating severity and frequency, and eating in the absence of hunger (EAH) in the laboratory. Fifty-nine individuals participated in an ostensible taste study after resting-state electroencephalogram (EEG) recordings. After the EEGs, they were provided a meal to eat until fullness, followed by an array of snacks and instructions to eat as much as they would like. The results indicated that several measures of right-frontal asymmetry were related to greater EAH and greater self-reported LOC eating severity. Although right-frontal asymmetry has been theorized to reflect avoidance motivation, recent evidence suggests it may indicate effortful control during approach-avoidance conflicts. Because individuals with LOC eating presumably experience heightened conflict between drives to eat beyond energy needs and to minimize such eating, those experiencing greater LOC may exert greater effort to manage these conflicting motivations. An integration of these neurobiological correlates of LOC eating may help provide a more comprehensive understanding of LOC eating and inform treatments.

Impaired belief updating and devaluation in adult women with bulimia nervosa.

Recent models of bulimia nervosa (BN) propose that binge-purge episodes ultimately become automatic in response to cues and insensitive to negative outcomes. Here, we examined whether women with BN show alterations in instrumental learning and devaluation sensitivity using traditional and computational modeling analyses of behavioral data. Adult women with BN (n = 30) and group-matched healthy controls (n = 31) completed a task in which they first learned stimulus-response-outcome associations. Then, participants were required to repeatedly adjust their responses in a "baseline test", when different sets of stimuli were explicitly devalued, and in a "slips-of-action test", when outcomes instead of stimuli were devalued. The BN group showed intact behavioral sensitivity to outcome devaluation during the slips-of-action test, but showed difficulty overriding previously learned stimulus-response associations on the baseline test. Results from a Bayesian learner model indicated that this impaired performance could be accounted for by a slower pace of belief updating when a new set of previously learned responses had to be inhibited (p = 0.036). Worse performance and a slower belief update in the baseline test were each associated with more frequent binge eating (p = 0.012) and purging (p = 0.002). Our findings suggest that BN diagnosis and severity are associated with deficits in flexibly updating beliefs to withhold previously learned responses to cues. Additional research is needed to determine whether this impaired ability to adjust behavior is responsible for maintaining automatic and persistent binge eating and purging in response to internal and environmental cues.

Weight status is associated with clinical characteristics among individuals with bulimia nervosa.

Recent studies have found increasing rates of overweight and obesity in bulimia nervosa (BN). However, the relationships between body mass index (BMI) and BN symptoms and other clinically relevant constructs are unknown. Participants (N = 152 adults with BN) were assigned to three groups by BMI: group with no overweight or obesity (NOW-BN; BMI <25; N = 32), group with overweight (OW-BN; BMI ≥25 and <30; N = 66), and group with obesity (O-BN; BMI ≥30; N = 54). We compared the groups on demographics, diet and weight histories, body esteem, BN symptoms, and depression using chi square, analysis of variance, analysis of covariance, and Poisson regression models. The O-BN group was older (d = 0.57) and OW-BN and O-BN groups had greater proportions of race/ethnic minorities than NOW-BN group. The O-BN group was significantly younger at first diet (d = 0.41) and demonstrated significantly higher cognitive dietary restraint (d = 0.31). Compared to NOW-BN, O-BN participants had lower incidence of objective binge eating (incidence rate ratio [IRR] = 4.86) and driven exercise (IRR = 7.13), and greater incidence of vomiting (IRR = 9.30), laxative misuse (IRR = 4.01), and diuretic misuse (d = 2.08). O-BN participants also experienced higher shape (d = 0.41) and weight (d = 0.42) concerns than NOW-BN and OW-BN, although NOW-BN experienced higher shape (d = 0.44) and weight (d = 0.39) concerns than OW-BN. Groups did not differ on depression scores. These results were replicated when examining BMI as a continuous predictor across the full sample, with the exception of objective binge eating and driven exercise, which were not significantly associated with BMI. Individuals with BN and comorbid obesity have distinct clinical characteristics. Existing interventions may need to be adapted to meet clinical needs of these individuals.

Correcting the reward imbalance in binge eating: A pilot randomized trial of reward re-training treatment.

Behavioral treatments for psychological disorders characterized by reward-driven maladaptive behaviors (e.g., substance use disorder, eating disorders, behavioral addictions) primarily seek to reduce hyper-reward response to disorder-specific stimuli. Suboptimal outcomes for these treatments highlight the need to also target hypo-reward response to day-to-day life activities. The present study sought to conduct an initial test of a novel behavioral treatment, Reward Re-Training (RRT) to target hyper- and hypo-reward response in individuals with binge eating. Individuals with binge eating (N = 23) were randomly assigned to either 10 weeks of outpatient, group-based RRT treatment or a waitlist control. RRT was found to be feasible and acceptable, demonstrated large impacts on both hypo- and hyper-reward response (measured by self-report (pre-to post-treatment ηp2 range 0.38-0.58) and neural activation via fMRI), and was efficacious in reducing eating disorder pathology (ηp2 range 0.40-0.64, including binge eating, ηp2 = 0.64) compared to waitlist control (ηp2 range 0.00-0.04). This pilot data provides preliminary support for the feasibility, acceptability, and effectiveness of a novel treatment targeting reward imbalance for individuals with binge eating. Future evaluations of RRT may benefit from an active treatment comparison condition and a follow-up assessment to examine persistence of positive outcomes.

The effect of weight suppression on eating behavior: Does the intentionality of weight loss matter?

Weight suppression (WS) has been consistently related to eating pathology. The weight loss that produces weight suppression has always been assumed to be intentional, but no study has tested whether unintentional weight loss would also be associated with eating pathology. The current study examined whether the association between WS and eating pathology may be moderated by intentionality of weight loss in a community-based sample of 520 adults. Participants were categorized into low WS (<5% weight loss from highest past weight), intentional, high WS (>5% intentional weight loss), and unintentional, high WS (>5% unintentional weight loss) groups. The intentional WS group reported greater restraint than the unintentional WS and low WS groups, and the low WS group reported greater restraint and more frequent loss-of-control (LOC) eating than those with unintentional WS. Further, WS was positively related to loss-of-control eating frequency only in the intentional WS group, and negatively associated with LOC eating frequency in the low WS group. Additionally, BMI was positively associated with LOC and binge eating frequency and restraint only in the low WS group. Given the relatively high prevalence of substantial but unintended weight loss found in this study, researchers studying weight suppression should consider asking about intentionality of weight loss and analyzing their data with and without unintentional weight suppressors included in the sample.

Evaluating the use of lamotrigine to reduce mood lability and impulsive behaviors in adults with chronic and severe eating disorders.

BACKGROUND: Gold-standard psychological and pharmacological treatments for bulimic-spectrum eating disorders only result in remission for around 50% of patients; patients with affective lability and impulsivity represent a subgroup with particularly poor outcomes. Both dialectical behavior therapy (DBT), a treatment for emotion dysregulation, and lamotrigine, a mood stabilizer, have demonstrated promise for targeting affective lability and impulsivity; however, data exploring the combination of these interventions remain limited. OBJECTIVE: We followed a group of women with recurrent dysregulated eating behaviors (N = 62) throughout intensive DBT treatment and compared the symptom trajectory of those prescribed lamotrigine (n = 28) and those who were not (n = 34). METHOD: Participants completed surveys every 2 weeks throughout treatment. RESULTS: Group analyses suggested that all participants self-reported decreases in emotional reactivity, negative urgency, and symptoms of borderline personality disorder (BPD). The lamotrigine group reported greater elevations in BPD symptoms at baseline, but demonstrated steeper decreases in emotion and behavioral dysregulation than the non-matched comparison group. Within-subject analyses suggested that within the lamotrigine group, subjects reported greater decreases in symptoms following prescription of lamotrigine. CONCLUSIONS: Findings provide initial data suggesting that lamotrigine could be useful as an adjunctive treatment for patients with affective lability and impulsivity. LEVEL OF EVIDENCE: IV, time series without randomization.

The food restriction wars: Proposed resolution of a primary battle.

Research regarding the definition and consequences of dieting has generated controversy for years. This controversy has spilled over into the public domain, especially as eating disorders and obesity have become more prevalent. One of the earliest and longest-lasting controversies involves the restrained eating framework, which was originally developed by Herman and Polivy and also strongly influenced the development of the cognitive-behavioral model of bulimia nervosa. An alternative framework for understanding the role of dieting in nonclinical and clinical groups, called the Three-Factor Model of Dieting, took a sharply different approach to defining, and understanding the impact of, dieting. This paper provides a brief historical review of the development of these divergent perspectives and updates the Three Factor Model's critical distinction between restraining eating to prevent over-consumption and dieting to lose weight. We suggest that three historical trends impacted the development of Restraint Theory in ways that unfairly impugned dieting for weight control: the emergence of the new eating disorders of bulimia nervosa and binge eating disorder, a population-based increase in loss of control eating and a population-based increase in obesity. This update is aimed in part at encouraging new research to reconcile ongoing, unresolved issues between Herman and Polivy's restrained eating model and the Three-Factor model of Dieting model. Such research might also contribute to the public's understanding of the pros and cons of dieting and to new approaches to treating eating disorders and obesity.

Within-subject weight variability in bulimia nervosa: Correlates and consequences.

OBJECTIVE: The oscillations between binge eating, purging, and dieting in bulimia nervosa (BN) may produce substantial within-subject weight variability. Although weight variability has been predictive of eating- and weight-related variables in community samples, it has not been empirically examined in eating disorders. The current study examined cross-sectional and prospective associations between weight variability and BN pathology. METHOD: Four weights were collected over an average of 42.02 days, and weight variability was calculated as the root mean square error around each individual's weight trajectory regression line. Linear regressions were performed to examine the association between weight variability and eating disorder psychopathology, cross-sectionally at baseline and prospectively at 6-month follow-up, adjusting for baseline BMI. RESULTS: Weight variability was cross-sectionally associated with eating pathology, but these relationships became non-significant after adjusting for BMI. However, at 6-month follow-up, greater baseline weight variability predicted increases in body dissatisfaction, shape and weight concerns, and global eating pathology, even after adjusting for baseline BMI. DISCUSSION: These findings demonstrate, for the first time, that within-subject weight variability predicts greater eating disorder pathology over time in BN. The results add to evidence that weight history variables contribute to BN psychopathology above and beyond well-documented psychological dysfunction in BN.

Associations of elevated weight status with symptom severity and treatment outcomes in binge/purge eating disorders.

OBJECTIVE: Binge-eating and purging behaviors commonly co-occur with overweight. However, little is known about the potential associations of elevated weight status with eating disorder severity or treatment outcomes. Thus, the present study compared binge-eating and purging patients with low, normal, and high weight statuses on eating disorder and mood symptoms at treatment admission, and tested whether weight status was associated with symptom change over treatment. METHOD: The sample included 135 adult female patients in an intensive outpatient program, who completed self-assessments at admission and discharge. MANOVAs compared the groups at treatment admission, and multilevel models examined changes over time. RESULTS: At admission, the high-weight group reported greater fasting frequency than the normal-weight group, and higher shape and weight concerns than the low-weight group. Over time, the high-weight group additionally showed higher eating disorder psychological symptom severity than the normal-weight group. The groups did not differ on mood symptoms at admission. Longitudinal results indicated that the groups showed comparable symptom improvements over treatment. DISCUSSION: These findings highlight the severity of higher-weight patients with bulimia nervosa. Additionally, although these patients may present with more severe symptoms, their response to an intensive treatment may be comparable to that of normal- or lower-weight groups.

Emotion Regulation Difficulties During and After Partial Hospitalization Treatment Across Eating Disorders.

Emotion regulation deficits are associated with eating disorder (ED) symptoms, regardless of eating disorder diagnosis. Thus, recent treatment approaches for EDs, such as dialectical behavior therapy (DBT), have focused on teaching patients skills to better regulate emotions. The present study examined changes in emotion regulation among adult patients with EDs during DBT-oriented partial hospital treatment, and at follow-up (M[SD] = 309.58[144.59] days from discharge). Exploratory analyses examined associations between changes in emotion regulation and ED symptoms. Patients with anorexia nervosa, restricting (AN-R, n = 77), and binge-eating/purging subtype (AN-BP, n = 46), or bulimia nervosa (BN, n = 118) completed the Difficulties in Emotion Regulation Scale (DERS) at admission, discharge, and follow-up. Patients with BN demonstrated significant improvements across all facets of emotion dysregulation from admission to discharge and maintained improvements at follow-up. Although patients with AN-BP demonstrated statistically significant improvements on overall emotion regulation, impulsivity, and acceptance, awareness, and clarity of emotions, from admission to discharge, these improvements were not significant at follow-up. Patients with AN-R demonstrated statistically significant improvements on overall emotion dysregulation from treatment admission to discharge. Changes in emotion regulation were moderately correlated with changes in ED symptoms over time. Results support different trajectories of emotion regulation symptom change in DBT-oriented partial hospital treatment across ED diagnoses, with patients with BN demonstrating the most consistent significant improvements.

A pilot open series of lamotrigine in DBT-treated eating disorders characterized by significant affective dysregulation and poor impulse control.

BACKGROUND: There is little effective psychopharmacological treatment for individuals with eating disorders who struggle with pervasive, severe affective and behavioral dysregulation. METHODS: This pilot open series evaluated lamotrigine, a mood stabilizer, in the treatment of patients with eating disorders who did not respond adequately to antidepressant medications. Nine women with anorexia nervosa- or bulimia nervosa-spectrum eating disorders in partial hospital or intensive outpatient dialectical behavior therapy (DBT)-based eating disorder treatment took lamotrigine for 147 ± 79 days (mean final dose = 161.1 ± 48.6 mg/day). Participants completed standardized self-report measures of emotion dysregulation and impulsivity after lamotrigine initiation and approximately biweekly thereafter. Mood and eating disorder symptomatology were measured at lamotrigine initiation and at time of final assessment. RESULTS: Lamotrigine and concurrent DBT were associated with large reductions in self-reported affective and behavioral dysregulation (ps < 0.01). Eating disorder and mood symptoms decreased moderately. CONCLUSIONS: Although our findings are limited by the confounds inherent in an open series, lamotrigine showed initial promise in reducing emotional instability and behavioral impulsivity in severely dysregulated eating-disordered patients. These preliminary results support further investigation of lamotrigine for eating disorders in rigorous controlled trials.