A systematic review of reviews of neurocognitive functioning in eating disorders: The state-of-the-literature and future directions

Self-Regulation in Eating Behaviors: The Role of Executive Function in Response to Food Stimuli

Human nutrition is characterized by both automatic and self-regulated processes. One of the dimensions that may be employed in monitoring eating behaviors is the cognitive control played by the executive functions (EFs). The role of EFs in affecting eating behaviors has been assessed in empirical studies, but further analyses are needed in a current society characterized by a food-abundant environment. Accordingly, this study attempted to evaluate the association between weight status and executive functions in response to food-related stimuli. One hundred and forty-four young adults took part in the study (25.7% in overweight condition). The participants completed a set of computerized cognitive tasks to assess cognitive and motor inhibition and working memory in two different conditions: (i) classic versions of the tasks and (ii) modified versions with food cues. The results indicate that food stimuli may influence executive performance and that there is an association between food cue-related executive functioning, particularly in the domain of motor inhibition, and working memory. These results suggest that self-regulation in nutrition may involve executive control. Although further studies are needed, this work suggests the importance of a multidimensional perspective in the analysis of eating behaviors and the relevance of EFs in monitoring our approach to food stimuli in an environmental context.

Overlap of eating disorders and neurodivergence: the role of inhibitory control

BACKGROUND

Difficulties with inhibitory control have been identified in eating disorders (EDs) and neurodevelopmental disorders (NDs; including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder), and there appear to be parallels between the expression of these impairments. It is theorised that impairments in inhibitory control within NDs may represent a unique vulnerability for eating disorders (EDs), and this same mechanism may contribute to poorer treatment outcomes. This review seeks to determine the state of the literature concerning the role of inhibitory control in the overlap of EDs and neurodivergence.

METHOD

A scoping review was conducted to summarise extant research, and to identify gaps in the existing knowledge base. Scopus, Medline, PsycInfo, Embase, and ProQuest were systematically searched. Studies were included if the study measured traits of ADHD or autism, and symptoms of ED, and required participants to complete a performance task measure of inhibitory control. Where studies included a cohort with both an ND and ED, these results had to be reported separately from cohorts with a singular diagnosis. Studies were required to be published in English, within the last 10 years.

RESULTS

No studies explored the relationship between autism and EDs using behavioural measures of inhibitory control. Four studies exploring the relationship between ADHD and EDs using behavioural measures of inhibitory control met selection criteria. These studies showed a multifaceted relationship between these conditions, with differences emerging between domains of inhibitory control. ADHD symptoms predicted poorer performance on measures of response inhibition in a non-clinical sample; this was not replicated in clinical samples, nor was there a significant association with EDs. Both ADHD and ED symptoms are associated with poor performance on attentional control measures; where these diagnoses were combined, performance was worse than for those with a singular diagnosis of ADHD. This was not replicated when compared to those with only ED diagnoses.

CONCLUSION

Impairments in attentional control may represent a unique vulnerability for the development of an ED and contribute to poor treatment outcomes. Further research is needed to explore the role of inhibitory control in EDs, ADHD and autism, including the use of both self-report and behavioural measures to capture the domains of inhibitory control.

Similarities and differences between eating disorders and obsessive-compulsive disorder in childhood and adolescence: a systematic review

Background

The developmental age, comprising childhood and adolescence, constitutes an extremely important phase of neurodevelopment during which various psychiatric disorders can emerge. Obsessive-Compulsive Disorder (OCD) and Eating Disorders (ED) often manifest during this critical developmental period sharing similarities but also differences in psychopathology, neurobiology, and etiopathogenesis. The aim of this study is to focus on clinical, genetic and neurobiological similarities and differences in OCD and ED.

Methods

This study is based on a PubMed/MEDLINE and Cochrane Central Register for Controlled Trial (CENTRAL). The research adhered to the guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

Results

The aforementioned search yielded an initial collection of 335 articles, published from 1968 to September 2023. Through the application of inclusion and exclusion criteria, a total of 324 articles were excluded, culminating in a final selection of 10 articles.

Conclusions

Our findings showed both differences and similarities between OCD and ED. Obsessive-compulsive (OC) symptoms are more prevalent in ED characterized by a binge/purge profile than in those with a restrictive profile during developmental age. OC symptomatology appears to be a common dimension in both OCD and ED. When presents, OC symptomatology, exhibits transversal characteristic alterations in the anterior cingulate cortex and poorer cognitive flexibility. These correlations could be highlighted by genetic overlaps between disorders. A comprehensive definition, integrating psychopathological and neurobiological aspects could significantly aid treatment selection and thereby influence the prognosis of these patients.

[Effects of non-invasive neuromodulation on the cognitive profile of people with anorexia nervosa: A scoping review]

BACKGROUND

The use of non-invasive neuromodulation is emerging in the treatment of anorexia nervosa. Despite promising results, further research is needed to improve our understanding of these techniques and to adapt interventions to this population. As anorexia nervosa is associated with several cognitive difficulties and cerebral anomalies, the aim of the present study was to summarize the available data on the effects of non-invasive neuromodulation on the neuropsychological profile of people with anorexia nervosa.

METHOD

A scoping review was conducted by searching in PsycINFO, PubMed and CINAHL databases to systematically identify relevant studies published between 1994 and 2023 on the treatment of anorexia nervosa with repetitive transcranial magnetic stimulation, transcranial direct current stimulation or neurofeedback electroencephalogram.

RESULTS

Seventeen articles were included, including 12 on repetitive transcranial magnetic stimulation, four on transcranial direct current stimulation and one on neurofeedback electroencephalogram. Of these, only three studies included a neuropsychological measure to assess the impact of neuromodulation on participants' cognitive functions.

CONCLUSIONS

Including detailed neuropsychological measures in clinical trials of non-invasive neuromodulation is highly recommended and appears essential to improve our understanding of these techniques and optimize their efficacy in the treatment of anorexia nervosa.

The importance of improving cognitive flexibility in adolescents with anorexia nervosa: The case for cognitive remediation therapy

OBJECTIVE

Inefficiencies in executive functioning (EF), more specifically cognitive flexibility and an overly detailed processing style, are frequently observed in individuals with Anorexia Nervosa (AN) and have been identified as potential targets in treatment. Cognitive Remediation Therapy (CRT) is an adjunctive treatment approach specifically designed to have a positive impact on EF. Mainly evaluated in adults, CRT has been criticized for its perceived ineffectiveness in promoting weight restoration or directly reducing eating disorder symptoms.

METHOD

We argue that we need to refocus our conceptual framework for using CRT as an adjunctive treatment and specifically explore its potential benefit in adolescents.

RESULTS

Adolescence is a critical window for EF development during which CRT has the potential to have the most impact. While it may not specifically ameliorate eating disorder symptoms and directly improve weight gain, CRT may mitigate the impact of malnutrition on adolescent brain development, reduce attrition rates in treatment, and improve cognitive flexibility and (indirectly) other maintaining factors, thereby improving global functioning.

DISCUSSION

More research needs to be done to understand the development of EF in adolescents with AN and how best to employ CRT as an adjunctive treatment to support development and target maintaining factors. The current article broadly reviews findings on executive functioning inefficiencies in adolescents with AN and discusses the purpose and role of CRT in treating AN. Finally, we highlight key critiques of using CRT and pose questions for future research.

PUBLIC SIGNIFICANCE

Treatments targeting executive functioning in adolescents with AN are limited. We need to better understand how CRT can benefit adolescents in treatment. Increasing treatment options, including adjunctive treatments, is necessary to reduce the long-term impact of AN.

Psilocybin restrains activity-based anorexia in female rats by enhancing cognitive flexibility: contributions from 5-HT1A and 5-HT2A receptor mechanisms

Psilocybin has shown promise for alleviating symptoms of depression and is currently in clinical trials for the treatment of anorexia nervosa (AN), a condition that is characterised by persistent cognitive inflexibility. Considering that enhanced cognitive flexibility after psilocybin treatment is reported to occur in individuals with depression, it is plausible that psilocybin could improve symptoms of AN by breaking down cognitive inflexibility. A mechanistic understanding of the actions of psilocybin is required to tailor the clinical application of psilocybin to individuals most likely to respond with positive outcomes. This can only be achieved using incisive neurobiological approaches in animal models. Here, we use the activity-based anorexia (ABA) rat model and comprehensively assess aspects of reinforcement learning to show that psilocybin (post-acutely) improves body weight maintenance in female rats and facilitates cognitive flexibility, specifically via improved adaptation to the initial reversal of reward contingencies. Further, we reveal the involvement of signalling through the serotonin (5-HT) 1 A and 5-HT2A receptor subtypes in specific aspects of learning, demonstrating that 5-HT1A antagonism negates the cognitive enhancing effects of psilocybin. Moreover, we show that psilocybin elicits a transient increase and decrease in cortical transcription of these receptors (Htr2a and Htr1a, respectively), and a further reduction in the abundance of Htr2a transcripts in rats exposed to the ABA model. Together, these findings support the hypothesis that psilocybin could ameliorate cognitive inflexibility in the context of AN and highlight a need to better understand the therapeutic mechanisms independent of 5-HT2A receptor binding.

Weak central coherence, cognitive rigidity and disordered eating in a community sample

Recent evidence has highlighted that a moderate degree of disordered eating has become the norm among the general population. While previous research has demonstrated that individuals with eating disorders exhibit heightened weak central coherence (i.e., attention to detail) and cognitive rigidity, and this plays a key role in the development and maintenance of the disorders, less is known about the relationship between disordered eating and these cognitive styles in subclinical community samples. A community sample of females completed self-report measures of weak central coherence, cognitive rigidity and eating disorder pathology. Unlike previous studies in the area, we first excluded participants with a diagnosis of eating disorder and then confined the analyses to those without clinically significant disordered eating. In line with the clinical literature, we found both cognitive rigidity and weak central coherence to correlate with severity and frequency of disordered eating behaviours and cognitions, suggesting the relationship also exists in subclinical samples. If replicated and expanded upon, these findings may bear important implications for the prevention and early identification of disordered eating in the community.

Executive function differences as a function of parent-reported binge eating and weight: Results from the adolescent brain cognitive development study

Background

Binge eating is a relatively common disordered eating behavior among children, and is associated with poor health outcomes. Executive function (EF)-higher order cognitive abilities related to planning and impulse control-may be implicated in both binge eating and pediatric obesity. Although EF deficits are evident among individuals with obesity and/or binge eating, findings are mixed across the lifespan.

Methods

The present study examined differences in EF among children with varying weight statuses and parent-reported binge eating. The sample included 10,017 children from the Adolescent Brain Cognitive Development study, aged 9-10 years.

Results

Children with parent-reported binge eating-either with overweight/obesity or normal weight-had significantly lower EF than those with no binge eating and a normal weight status but did not differ from those with no binge eating and overweight/obesity. Children with no binge eating and overweight/obesity also had statistically significantly lower EF than those with normal weight status. Although all significant differences between groups were negligible to very small, results may indicate similar neurocognitive profiles among children with binge eating and those with overweight/obesity.

Conclusions

Alterations in EF among children with binge eating may not be solely related to weight-specific factors, as significant differences also emerged among children with normal weight status, with versus without parent-reported binge eating. Future research is needed to understand temporal associations between obesity, disordered eating, and neurocognition in children using multi-informant methods for assessing binge eating.

Psychologically informed care of patients with anorexia nervosa on an acute medical ward

Anorexia nervosa is a challenging and highly distressing illness associated with significant and often debilitating symptoms that affect the person's physical and mental well-being, as well as their wider social networks. Although some patients can make important steps in their recovery in the community, many will become significantly unwell and require medical stabilisation and refeeding in an acute medical ward as a result of significant weight loss. This article describes some of the challenges experienced by adult nurses when caring for patients with anorexia nervosa on acute medical wards and explores how the patient's distress may manifest and complicate the recovery process. The article also discusses the principles of psychologically informed care and therapeutic interactions that nurses can use to promote recovery and ensure optimal practice.

Task fMRI studies investigating inhibitory control in patients with obsessive-compulsive disorder and eating disorders: A comparative meta-analysis

BACKGROUND

Obsessive-compulsive disorder (OCD) and eating disorders (EDs) share similarities in terms of clinical characteristics and deficits in inhibitory control.

OBJECTIVE

To investigate whether inhibitory control could serve as a common behavioural phenotype between OCD and EDs and whether it might be underpinned by shared and/or distinct neural signatures.

METHOD

We performed a quantitative meta-analysis of brain function abnormalities during the inhibitory control task-based functional Magnetic Resonance Imaging (fMRI) scan across patients with OCD and EDs using seed-based d mapping (SDM).

RESULTS

The meta-analysis included sixteen OCD fMRI studies and ten EDs fMRI studies. And findings revealed that patients with OCD showed hypoactivation relative to healthy controls and patients with EDs in the anterior cingulate cortex, while compared to healthy controls and patients with OCD, patients with EDs showed hypoactivation in the right insula.

CONCLUSIONS

Patients with OCD and EDs are inclined to exhibit impaired inhibitory control, which may be attributed to different abnormal patterns of neural activation.

Validating and developing a shortened version of the detail and flexibility (DFlex) questionnaire for eating disorders, anxiety and depression

OBJECTIVE

To validate the original and a shortened version of the Detail and Flexibility (DFlex) Questionnaire.

METHOD

Confirmatory factor analyses, internal consistency, and discriminant validity estimates were conducted within individuals with a diagnosis of an eating disorder (ED) (n = 124), an anxiety disorder and/or depression (n = 219), and a community sample (n = 852) (Part 1). Convergent validity of the DFlex through comparisons with the Autism Spectrum Quotient, Wisconsin Card Sorting Task, and Group Embedded Figures Task was undertaken within a combined ED and community sample (N = 68). Test-retest reliability of the DFlex was also examined across 2 years in a community sample (N = 85) (Part 2).

RESULTS

The original factor structure of the DFlex was not supported. Hence, a shortened version, the DFlex-Revised, was developed. Good discriminant validity was obtained for the DFlex and DFlex-Revised, however, support for convergent validity was mixed. Finally, the 2-year test-retest reliability for the two DFlex versions was found to be low, suggesting potential malleability in construct over this timeframe.

CONCLUSIONS

Further research is needed to validate the DFlex in clinical and non-clinical populations using different neurocognitive tests. Test-retest, using varied time intervals, should also be assessed.

Exploring the relationship between emotion regulation, inhibitory control, and eating psychopathology in a non-clinical sample

OBJECTIVE

The present study aimed to explore the relationship between difficulties in emotion regulation and deficits in inhibitory control, and the role of these processes in eating psychopathology in a non-clinical sample. We also explored the specificity in which deficits in inhibitory control may underlie eating psychopathology, namely whether they can be conceptualised as context specific or more extensive in nature.

METHOD

Participants were 107 healthy individuals recruited at a major Portuguese university, aged between 18 and 43 years-old (M = 21.23, SD = 4.79). Two computerised neuropsychological tasks (i.e., emotional go/no-go and food go/no-go tasks) were used to assess response inhibition in the presence of general versus context-specific stimuli. A set of self-report measures was used to assess variables of interest such as emotion regulation and eating psychopathology.

RESULTS

Results indicated higher response inhibition deficits among participants with higher difficulties in emotion regulation comparing to those with lower difficulties in emotion regulation, particularly in the context of food-related stimuli. In addition, the relationship between difficulties in emotion regulation and eating psychopathology was moderated by inhibitory control deficits in both the context of food and pleasant stimuli.

CONCLUSIONS

The present findings highlight inhibitory control as an important process underlying the relationship between difficulties in emotion regulation and eating psychopathology in non-clinical samples. Findings have important implications for clinical practice and the prevention of eating psychopathology in healthy individuals and individuals with eating disorders.

A Behavioral and Event-Related Potentials Study of Food-Related Inhibitory Control in Probable Binge Eating Disorder

Background

Similar to addictive disorders, deficits on cognitive control might be involved in the onset and development of Binge Eating Disorder (BED). However, it remains unclear whether general or food-related inhibitory control impairments would be basically linked to overeating and binge eating behaviors. This study thus aimed to investigate behavioral performance and electrophysiological correlates of food-related inhibitory control among individuals with binge eating behavior.

Methods

Sixty individuals with probable BED (pBED) and 60 well-matched healthy controls (HCs) were assessed using the typical Stop-Signal Task, a revised Go/No Go Task, and a food-related Go/No Go Task. Besides, another separate sample, including 35 individuals with pBED and 35 HCs, completed the food-related Go/No Go Task when EEG signals were recorded with the event-related potentials (ERPs).

Results

The data revealed that the pBED group performed worse with a longer SSRT on the Stop-Signal Task compared with HCs (Cohen's d = 0.58, p = 0.002). Moreover, on the food-related Go/No Go Task, the pBED group had a lower success rate of inhibition in no-go trials (Cohen's d = 0.47, p = 0.012). The ERPs data showed that in comparison with HCs, the pBED group exhibited increased P300 latency (FC1, FC2, F3, F4, FZ) in the no-go trials of the food-related Go/No Go Task (Cohen's d 0.56-0.73, all p < 0.05).

Conclusion

These findings suggested that individuals with binge eating could be impaired in both non-specific and food-related inhibitory control aspects, and the impairments in food-related inhibitory control might be linked to P300 abnormalities, implying a behavioral-neurobiological dysfunction mechanism implicated in BED.

Childhood hyperactivity, eating behaviours, and executive functions: Their association with the development of eating-disorder symptoms in adolescence

BACKGROUND

Cross-sectional studies have shown that hyperactivity and impaired executive functioning are associated with symptoms of eating disorders in adolescence and adulthood. Whether hyperactivity and executive functions in early life can prospectively predict the emergence of eating disorder symptoms in adolescence remains unknown. The present study relies on a longitudinal design to investigate how hyperactivity at age 3, eating behaviours at age 3.5 and cognition at ages 3-6 were associated with the development of eating-disorder symptoms from 12 to 20 years old.

METHODS

Using archival data collected since 1997 from the Quebec Longitudinal Study of Child Development cohort (N = 2, 223), we used Latent Curve Models to analyse predictors of youth's trajectories of eating-disorder symptoms at four timepoints.

RESULTS

A quadratic (curvilinear) trajectory of eating-disorder symptoms was found to be most representative of the data. Higher hyperactivity at age 3 was associated with higher levels of eating-disorder symptoms at age 12, and this association was partially mediated by higher levels of overeating and cognitive inflexibility in childhood. Cognitive inflexibility in childhood also mediated the association between hyperactivity at age 3 and increases in eating-disorder symptoms during adolescence. Furthermore, working memory was indirectly related to eating-disorder symptoms via the mediational role of cognitive flexibility.

CONCLUSIONS

Hyperactivity, overeating, cognitive inflexibility, and working memory early in life might precede the onset of eating-disorder symptoms in adolescence. Early behavioural and cognitive screening may help to identify children who are most at risk for eating disorders. This, in turn, could guide preventive interventions.

Cognitive flexibility and DSM-5 severity criteria for eating disorders: assessing drive for thinness and duration of illness as alternative severity variables

BACKGROUND

The severity criteria for eating disorders (EDs) proposed in the DSM-5 have been established without sufficient empirical support. Drive for thinness (DT) and duration of illness have been proposed as two alternative severity measures, however their empirical evidence is also limited. To date, no research has assessed the validity of current eating disorder (ED) severity criteria regarding cognitive flexibility factors. Cognitive flexibility is often impaired in EDs, becoming a possible severity symptom. The current study assessed for the first time (1) whether the severity indexes for EDs proposed in the DSM-5 were associated with deficits in cognitive flexibility and, (2) whether drive for thinness and illness duration, acted as an alternative, more meaningful severity indices for deficiencies in cognitive flexibility.

METHODS

Participants were 161 patients diagnosed with an ED, who were categorized according to DSM-5 severity categories, DT and duration of illness. Discriminative capacity of each classification was assessed for cognitive flexibility measured by Wisconsin card sorting test (WCST).

RESULTS

The findings for the DSM-5 classification comprised: (a) In the anorexia nervosa (AN) group, patients with moderate severity showed better scores in WCST than patients with mild and severe/extreme severity. Also, patients with moderate severity showed lower percentage of cognitive flexibility deficits than the other two severity categories; (b) For the binge spectrum disorders (BSD) group, the patients with mild severity showed a higher percentage of cognitive flexibility deficits than did the moderate and severe/extreme categories. When assessing the alternative severity index of DT, no differences were found in cognitive flexibility in any of the groups. Regarding illness duration, in the AN group the task performance of the patients with longer illness duration was worse than the performance of the short duration group and, in the BSD group, patients with longer duration also showed more deficits in cognitive flexibility than the patients with shorter duration of illness.

CONCLUSIONS

Our findings point out the limitations of the DSM-5 severity criteria to categorize cognitive flexibility in EDs and support illness duration as an alternative severity approach for EDs.

Dysfunctional decision-making in binge-eating disorder: A meta-analysis and systematic review

Binge-Eating Disorder (BED) involves anticipatory craving and urges, subjective loss-of-control during binge-eating episodes, and post-feeding psychological distress and guilt. Evidence indicates neurocognitive dysfunctions contribute to BED onset, maintenance, and treatment response. However, an integrated understanding of how cognitive processes underpin BED symptomology is lacking. We utilised a multi-stage decision-making model defining ten cognitive processes underpinning Preference Formation, Choice Implementation, Feedback Processing, and Flexibility/Shifting, to comprehensively review research published since 2013. We used preregistered PICOS criteria to assess 1966 articles identified from PubMed, PsycInfo, and Scopus database searches. This yielded 50 studies reporting behavioural cognitive tasks outcomes, comparing individuals with BED to controls with normal and higher weight. Meta-analyses revealed a unique profile of cognitive dysfunctions that spanned all decision-making stages. Significant deficits were evident in Uncertainty Evaluation, Attentional Inhibition, Choice Consistency, and Cognitive Flexibility/Set-shifting. We propose a novel model of dysfunctional decision-making processes in BED and describe their role in binge-eating behaviour. We further highlight the potential for cognitive interventions to target these processes and address the significant treatment gap in BED.

Integrating aspects of affect, reward, and cognition to develop more comprehensive models of binge-eating pathology

Reward-related processes are an increasing focus of eating disorders research. Although evidence suggests that numerous distinct reward processes may contribute to eating pathology (e.g., reward learning and delay discounting), existing etiological models of reward dysfunction tend to focus on only a limited number of reward processes, and frequently lack specificity when identifying the individual reward processes hypothesized to contribute to dysregulated eating behavior. Moreover, existing theories have been limited in their integration of reward-related processes with other demonstrated risk and maintenance factors for eating disorders (e.g., affect and cognition), potentially contributing to underdeveloped models of eating pathology. In this article, we highlight five distinct reward processes with theorized or demonstrated relevance to eating disorders involving binge-eating, followed by a review of two well-established risk/maintenance factors for binge-eating pathology. We then introduce two novel models of binge eating onset and maintenance that integrate these factors (i.e., the Affect, Reward, Cognition models), and discuss methods for testing each of the models in future research. Ultimately, we hope that the proposed models provide a springboard for the continued evolution of more precise and comprehensive theories of reward dysfunction in the eating disorders, as well as the development of novel intervention approaches. PUBLIC SIGNIFICANCE STATEMENT: Eating disorders are associated with abnormalities in multiple domains of reward functioning. However, models of reward dysfunction within the eating disorders have not been well-integrated with prominent models of affect and cognition. This article presents two novel models of onset and maintenance for binge-eating pathology, which attempt to integrate observed reward abnormalities with other affective and cognitive processes implicated in binge-type eating disorders.

Measuring cognitive flexibility in anorexia nervosa: Wisconsin Card Sorting Test versus cued task-switching

PURPOSE

The Wisconsin Card Sorting Test (WCST) is the most common measure of cognitive flexibility in anorexia nervosa (AN), but task-switching paradigms are beginning to be utilized. The current study directly compared performance on a cued task-switching measure and the WCST to evaluate their association in participants with a lifetime diagnosis of AN, and to assess which measure is more strongly associated with clinical symptoms.

METHODS

Forty-five women with a lifetime diagnosis of AN completed the WCST, cued color-shape task-switching paradigm, Anti-saccade Keyboard Task, Running Memory Span, Eating Disorder Examination Questionnaire, Depression Anxiety Stress Scales short form and Eating Disorder Flexibility Index.

RESULTS

There was no evidence of a significant association between WCST perseverative errors and cued task-switching switch costs. Results suggest lower working memory capacity is a determinant of higher perseverative error rate. When controlling for mood variables, neither cognitive flexibility measure was a significant independent predictor of symptom severity.

CONCLUSIONS

Results provide support for previous suggestions that WCST perseverative errors could occur due to difficulties with working memory, sensitivity to feedback, and issues with concept formation. Cued task-switching paradigms may provide a useful measure of cognitive flexibility for future eating disorders research by reducing task-specific confounds.

LEVEL OF EVIDENCE

Level III Case-control analytic study.

The paradoxical moderating effects of metacognition in the relationships between self-esteem, depressive symptoms, and quality of life in anorexia and bulimia

BACKGROUND

Self-esteem and depressive symptoms contribute to a lower quality of life in people suffering from eating disorders. However, limited research has examined whether other factors may affect how these variables influence one another over time. Metacognition is a previously unexplored determinant that may impact the relationships between self-esteem, depressive symptoms, and quality of life in instances of eating disorders.

AIM

This study sought to examine metacognitive self-reflectivity and mastery as moderators of the relationships between self-esteem, depressive symptoms, and quality of life and to determine if these relationships are different in people with anorexia compared with people with bulimia.

METHODS

Participants with anorexia (n=40) and bulimia (n=40) were recruited from outpatient clinics. The participants were assessed on their metacognitive ability and self-reported on measures to assess their depressive symptoms, self-esteem, and quality of life.

RESULTS

The results indicate that metacognitive self-reflectivity moderates the relationship between self-esteem, depressive symptoms, and quality of life in people with anorexia such that when self-reflectivity is high, lower self-esteem and higher depressive symptoms are associated with a lower quality of life. These relationships did not appear to be significant when self-reflectivity was low. In contrast, in the anorexia and bulimia groups, metacognitive mastery appeared to moderate the relationships between self-esteem, depressive symptoms, and quality of life such that when mastery was low, lower self-esteem and higher depressive symptoms were associated with a lower quality of life. These relationships did not appear significant when mastery was high.

CONCLUSION

Metacognitive self-reflectivity and mastery seem to play paradoxical moderating roles in the relationships between self-esteem, depressive symptoms, and quality of life in people with anorexia and bulimia. These findings pave the way toward further research and have important clinical implications.

Associations of food reinforcement and food- related inhibitory control with adiposity and weight gain in children and adolescents

Some, but not all studies have reported that, among youth with disordered eating and high weight, the relative reinforcing value of food (RRV-F, i.e., how hard a person will work for a high-energy-dense food when another reward is available) is greater, and food-related inhibitory control (i.e., ability to withhold a response to food-related stimuli) is lower, compared to peers without disordered eating or overweight. In most studies, high RRV-F and low food-related inhibitory control have been studied separately, as independent factors, with each suggested to predict excess weight and adiposity (fat mass) gain. We hypothesized that the interaction of these factors would prospectively exacerbate risk for weight and adiposity (fat mass) gain three years later in a sample of healthy youth. At baseline, RRV-F was measured using a Behavior Choice Task with the rewards being standardized servings of chocolate candies, cheese crackers, or fruit snacks. Food-related inhibitory control was determined by performance in response to food and non-food stimuli during a Food Go/No-Go task. At baseline and 3-year visits, total body adiposity was measured by dual-energy X-ray absorptiometry (DXA) and body mass index (BMI) was obtained using measured weight and height. A linear regression was conducted with 3-year adiposity as the dependent variable. RRV-F, food-related inhibitory control, and the RRV-F x food-related inhibitory control interaction as independent variables. Baseline adiposity, age, height, sex, race/ethnicity, and days between visits were included as covariates for model predicting 3-year adiposity. Baseline BMI, age, sex, race/ethnicity, and days between visits were included as covariates for model predicting 3-year BMI. One-hundred and nine youth (mean 12.4±2.7y, mean 0.50±1.02 BMIz, 30.3% with overweight/obesity, 45.9% female, 51.4% non-Hispanic White), 8-17 years at baseline, were studied. Baseline food-related inhibitory control (βunstandardized = 0.33, p = .037, 95% CI [.02, 0.64]), but not baseline RRV-F (βunstandardized = -0.003, p = .914), 95% CI [-0.05, 0.05]) was significantly associated with 3-year adiposity such that those with the poorest food-related inhibitory control (great number of commision errors) had the greatest adiposity gain. The interaction between RRV-F and food-related inhibitory control did not predict 3-year adiposity (βunstandardized = -0.07, p = .648, 95% CI [-0.39, 0.25]). The pattern of findings was the same for models examining non-food related inhibitory control. Neither baseline food-related inhibitory control (βunstandardized = 2.16, p = .256, 95% CI [-1.59, 5.92]), baseline RRV-F (βunstandardized = 0.14, p = .660, 95% CI [-0.48, 0.75]), nor their interaction (βunstandardized = -1.18, p = .547, 95% CI [-5.04, 2.69]) were significantly associated with 3-year BMI. However, non-food related inhibitory control (βunstandardized = 0.54, p = .038, 95% CI [.22, 7.15]) was significantly associated with 3-year BMI. In summary, food-related inhibitory control but not RRV-F, was associated with changes in adiposity in a sample of children and adolescents. Among generally healthy youth, food-related inhibitory control may be a more relevant risk factor than food reinforcement for adiposity gain. Additional data are needed to determine how inhibitory control and reward systems, as well as other disinhibited eating behaviors/traits, may interact to promote excess weight gain over time in youth.

Daily ovarian hormone exposure and loss of control eating in adolescent girls: A registered report

OBJECTIVE

The daily biobehavioral factors that precipitate loss of control eating (LOCE) in adolescent girls are not well known. Ovarian hormone levels are key biological factors associated with the etiology of eating disorders in adolescent girls. Yet, models on how daily ovarian hormone exposure predicts LOCE in adolescent girls are underdeveloped. The goal of this study is to examine the daily patterns and mechanisms of ovarian hormone levels on LOCE across the menstrual cycle in adolescent girls and the mediating roles of food-related reward anticipation and response inhibition. Ecological momentary assessment (EMA) paired with daily hormonal sampling will be used to examine (1) daily associations between within-person hormones and LOCE, and (2) the mediating role of within-person food-related reward anticipation and response inhibition.

METHODS

Normally cycling adolescent girls who have reached menarche will provide daily saliva samples for hormone analysis and complete EMA for 35 days. During EMA, girls will report LOCE and will complete task-based and self-report measures of food-related response inhibition and reward anticipation.

DISCUSSION

This work has implications for the development of new real-world biobehavioral models of LOCE in adolescent girls, which will guide theory improvements and treatment for LOCE. Results will provide preliminary evidence for treatment targets for novel interventions for adolescent girls-for example, a response inhibition intervention.

PUBLIC SIGNIFICANCE

Adolescent eating disorders are severe mental health conditions, often marked by loss of control eating. Estrogen and progesterone play a role in the development and persistence of loss of control eating. The current study will examine how daily exposure to estrogen and progesterone predicts loss of control eating in adolescent girls and identify possible daily mechanisms linking estrogen and progesterone exposure and loss of control eating.

Prefrontal cortex activation by binge-eating status in individuals with obesity while attempting to reappraise responses to food using functional near infrared spectroscopy

PURPOSE

Difficulty reappraising drives to consume palatable foods may promote poorer inhibition and binge eating (BE) in adults with obesity, but neural underpinnings of food-related reappraisal are underexamined.

METHODS

To examine neural correlates of food-related reappraisal, adults with obesity with and without BE wore a portable neuroimaging tool, functional near-infrared spectroscopy (fNIRS). fNIRS measured activity in the prefrontal cortex while participants watched videos of food and attempt to "resist" the food stimuli (i.e., "consider the negative consequences of eating the food").

RESULTS

Participants (N = 32, 62.5% female; BMI 38.6 [Formula: see text] 7.1; 43.5 [Formula: see text] 13.4 y) had a BMI > 30 kg/m². Eighteen adults (67.0% female; BMI 38.2 [Formula: see text] 7.6) reported BE (≥ 12 BE-episodes in preceding 3 months). The control group comprised 14 adults who denied BE (64.0% female; BMI 39.2 [Formula: see text] 6.6). Among the entire sample, mixed models showed significant, small hyperactivation during crave and resist compared to watch (relax) condition bilaterally in the medial superior frontal gyrus, dorsolateral areas, and middle frontal gyrus (optodes 5, 7, 9, 10, 11, and 12) in the total sample. No statistically significant differences in neural activation were observed between the BE and control group. Moreover, there were no significant group by condition interactions on neural activation.

CONCLUSION

Among adults with obesity, BE status was not linked to differential activation in inhibitory prefrontal cortex areas during a food-related reappraisal task. Future research is needed with larger samples, adults without obesity, and inhibition paradigms with both behavioral and cognitive components.

LEVEL OF EVIDENCE

Level III: Evidence obtained from well-designed cohort or case-control analytic studies.

TRIAL REGISTRATION

# NCT03113669, date April 13, 2017.

Sizing up the crowd: Assessing spatial integration difficulties in body size judgements across eating disorder symptomatology

Introduction

Body size judgements are frequently biased, or inaccurate, and these errors are further exaggerated for individuals with eating disorders. Within the eating disorder literature, it has been suggested that exaggerated errors in body size judgements are due to difficulties with integration. Across two experiments, we developed a novel integration task, named the Ebbinghaus Illusion for Bodies in Virtual Reality (VR), to assess whether nearby bodies influence the perceived size of a single body. VR was used to simulate the appearance of a small crowd around a central target body.

Method and Results

In Experiment 1 (N = 412), participants were required to judge the size of a central female target within a crowd. Experiment 1 revealed an Ebbinghaus Illusion, in which a central female appeared larger when surrounded by small distractors, but comparatively smaller when surrounded by large distractors. In other words, the findings of Experiment 1 demonstrate that surrounding crowd information is integrated when judging an individual's body size; a novel measure of spatial integration (i.e., an Ebbinghaus Illusion for Bodies in VR). In Experiment 2 (N = 96), female participants were selected based on high (n = 43) and low (n = 53) eating disorder symptomatology. We examined whether the magnitude of this illusion would differ amongst those with elevated versus low eating disorder symptomatology, in accordance with weak central coherence theory, with the high symptomatology group displaying less spatial integration relative to the low group. The results of Experiment 2 similarly found an Ebbinghaus Illusion for Bodies in VR. However, illusion magnitude did not vary across high and low symptomatology groups.

Discussion

Overall, these findings demonstrate that surrounding crowd information is integrated when judging individual body size; however, those with elevated eating disorder symptomatology did not show any integration deficit on this broader measure of spatial integration.

Does seeking the brawns impact the brain?: An investigation of muscularity-oriented disordered behaviors and cognitive function

Shifts in body-image ideals over the past 30 years towards leaner, muscular bodies have revealed new health behaviors that may be related to cognitive function. This study objective was to investigate prospective associations between a drive for muscularity and/or muscularity-oriented disordered behaviors (MODBs) with cognition. Data were drawn from Add Health, a nationally representative longitudinal cohort dataset. Drive for muscularity and MODB engagement were assessed in emerging adulthood (ages 18-26). Cognition was measured via immediate word recall, delayed-word recall, and number recall at 7-years later (ages 24-32). Analyzes were conducted in 1976 participants with available data. A one-way ANCOVA revealed that those with a drive for muscularity had lower immediate word recall (F(3, 12,819) = 3.845, p = .009) and delayed word recall (F(3, 12,807) = 5.933, p < .001) scores than other weight goal groups adjusting for covariates. Hierarchical linear regressions between individual MODBs and cognitive outcomes showed that legal performance-enhancing substance use (βs = 0.06-0.07, p < .05) and exercise (β = 0.06, p < .05) were positively associated with some cognition scores. Conversely, lifting weights (β = - 0.06, p < .05) and eating different foods than usual (β = - 0.05, p < .05) exhibited negative associations with some of the cognitive outcomes. Future research should be conducted to examine other potential outcomes related to the drive for muscularity and associated MODBs.

Phonological working memory is adversely affected in adults with anorexia nervosa: a systematic literature review

PURPOSE

Cognitive restraint has potentiating and deleterious effects on working memory (WM) in anorexia nervosa (AN). Conflicting evidence may be due to heterogeneity of tasks examining different WM components (e.g., verbal/auditory versus visuospatial), and differences in adolescent versus adult AN. Additionally, differential cognitive profiles of restricting versus binge/purging subtypes, comorbid psychiatric disorders and psychotropic medication use may confound findings.

METHODS

To address these conflicts, 25 studies, published between 2016 and 2021, investigating WM in children, adolescents and adults with AN were systematically reviewed using PRISMA guidelines.

RESULTS

In 71% of WM tasks, no difference in performance between AN patients and age-matched controls was reported, while 29% of WM tasks showed worse performance. Adults with AN displayed deficits in 44% of the verbal/auditory tasks, while performance remained unaffected in 86% of visuospatial tasks.

CONCLUSION

Examining age groups and WM subsystems separately revealed novel findings of differentially affected WM components in AN. Comorbidities and psychotropic medications were common among AN participants and should be regarded as critical confounding factors for WM measures. Future studies examining different components of WM, acknowledging these confounding factors, may reveal specific deficits in AN to aid treatment improvement strategies.

LEVEL OF EVIDENCE

I, systematic review.

Adverse Childhood Experiences and Neurocognition in Borderline Personality Disorder: A Call-to-Action Perspective Review

Adverse childhood experiences (ACEs) contribute to the development of personality traits leading to adult borderline personality disorder (BPD). Neurocognitive changes could partly mediate the association between ACEs and BPD. We discuss how exposure to ACEs could induce alterations in neurocognition, which, in turn, would contribute to the development of BPD. We conducted a review of MEDLINE articles through 2021, documenting a link between ACEs, neurocognitive impairments, and BPD, and also focusing on the pairwise associations. ACEs appear to have a strong impact on neurocognition and are a predictive factor for BPD. Maltreated, abused, and emotionally invalidated children are more likely to present BPD traits. Neurocognitive impairments in adults exposed to ACEs and in patients with BPD arise from similar brain alterations in the amygdala, hippocampus, and prefrontal cortex. These impairments seem to be linked with clinical dimensions of BPD: increased impulsivity to altered inhibitory control; dissociative experiences to nonspecific autobiographical memory; and emotionally biased facial recognition to unstable interpersonal relationships. This perspective review highlights the contributory role of neurocognition in the association between ACEs and BPD. Additional research is needed, however, on the interconnections among ACEs, neurocognition, and BPD. Future studies could also focus on developing tools to assess early adversity in BPD specifically and on psychotherapeutic approaches to promptly remedy neurocognitive impairments.

Research Review: Neuropsychological functioning in young anorexia nervosa: A meta-analysis

BACKGROUND

Cognitive inflexibility and compulsive behaviours are commonly observed in patients with anorexia nervosa (AN) and are often considered to be caused by impairments in executive functioning and visuospatial processing. Despite an increasing number of young individuals presenting with AN, there is a lack of meta-analytic evidence on the neuropsychological functioning in this population. Our primary aim was to review and synthesize the differences in neuropsychological test performance between young people with AN and healthy controls, and to explore potential moderators.

METHODS

A database search following PRISMA guidelines of MEDLINE, PsycINFO, ISI Web of Science and Epistemonikos was conducted. Hedges' g served as an effect size indicating the standardized mean differences. We utilized mixed-effects meta-regression and machine learning meta-analyses to identify relevant moderators.

RESULTS

Sixteen studies met the inclusion criteria with a total of 1333 participants (665 with AN) and 59 effect sizes. Random-effects meta-analyses demonstrated a small and insignificant difference between young individuals with AN and controls ( g¯  = -0.144, 95% CI [-0.328, 0.041]) in overall neuropsychological functioning. However, the difference was significant for the cognitive domains of memory, working memory and visuospatial abilities. Moderator and machine-learning analyses revealed a stronger negative effect in older participants and moderator effects of country and assessment quality.

CONCLUSIONS

Our findings highlight the significant impact of age on neuropsychological test performance in patients with AN. There is a need for a more widespread inclusion of potentially confounding variables in primary studies as well as instruments specifically targeted at younger populations.

Targeting binge eating in bulimia nervosa and binge eating disorder using inhibitory control training and implementation intentions: a feasibility trial

BACKGROUND

This trial examined the feasibility, acceptability, and effect sizes of clinical outcomes of an intervention that combines inhibitory control training (ICT) and implementation intentions (if-then planning) to target binge eating and eating disorder psychopathology.

METHODS

Seventy-eight adult participants with bulimia nervosa or binge eating disorder were randomly allocated to receive food-specific, or general, ICT and if-then planning for 4 weeks.

RESULTS

Recruitment and retention rates at 4 weeks (97.5% and 79.5%, respectively) met the pre-set cut-offs. The pre-set adherence to the intervention was met for the ICT sessions (84.6%), but not for if-then planning (53.4%). Binge eating frequency and eating disorder psychopathology decreased in both intervention groups at post-intervention (4 weeks) and follow-up (8 weeks), with moderate to large effect sizes. There was a tendency for greater reductions in binge eating frequency and eating disorders psychopathology (i.e. larger effect sizes) in the food-specific intervention group. Across both groups, ICT and if-then planning were associated with small-to-moderate reductions in high energy-dense food valuation (post-intervention), food approach (post-intervention and follow-up), anxiety (follow-up), and depression (follow-up). Participants indicated that both interventions were acceptable.

CONCLUSIONS

The study findings reveal that combined ICT and if-then planning is associated with reductions in binge eating frequency and eating disorder psychopathology and that the feasibility of ICT is promising, while improvements to if-then planning condition may be needed.

Common Predictive Factors of Social Media Addiction and Eating Disorder Symptoms in Female College Students: State Anxiety and the Mediating Role of Cognitive Flexibility/Sustained Attention

This study aimed to investigate the common predictive factors between social media addiction (SMA) and eating disorder symptoms (EDS), in a group of Chinese female college students. A total of 216 students completed the behavioral assessments of cognitive flexibility and sustained attention, as well as the questionnaires on anxiety, social media dependence, and eating disorders. The results indicate that SMA is significantly correlated with EDS. Structural equation modeling was used to test the model in which state anxiety, cognitive flexibility, and sustained attention predicted social gain and EDS. Additionally, the results confirmed the mediating role of cognitive flexibility and sustained attention between state anxiety and SMA/EDS in the participants. The findings revealed that in the sample group, state anxiety was related to SMA and EDS through cognitive flexibility and sustained attention. These proposals reflect the significance of improving cognitive flexibility/sustained attention and reducing state anxiety to prevent EDS and SMA in female college students.

Olfactory capacity in anorexia nervosa: correlations with set-shifting ability

PURPOSE

The purpose of this study is to examine olfactory capacity in adults with anorexia nervosa (AN), in terms of odor identification and odor threshold and search for possible correlations between odor identification and cognitive flexibility in this population.

METHODS

Thirty-nine patients diagnosed with AN and 60 healthy participants, participated. Odor identification was assessed using the University Pennsylvania Smell Identification Test and a two alternative forced choice, ascending method with n-butanol was used to assess odor threshold. Cognitive flexibility was determined using the Intra/Extra-Dimensional Set-Shift test (IED), a subtest of the Cambridge Neuropsychological Test Automated Battery (CANTAB).

RESULTS

Patients with AN presented a poorer performance in odor identification compared with controls (p = 0.001). No differences were found in odor threshold, between the two groups. Patients with AN exhibited poor cognitive flexibility compared with controls (p = 0.003). A significant correlation between odor identification and cognitive flexibility was documented in AN (p = 0.01), but not in controls.

CONCLUSION

Our findings suggest that olfactory capacity is altered in AN: Qualitative characteristics of olfaction were affected in patients with AN (lower odor identification), while there was no difference in quantitative characteristics (odor threshold) compared with controls. Furthermore, odor identification in AN was correlated to cognitive flexibility.

LEVEL OF EVIDENCE

Level III: case-control analytic study.

Cognitive flexibility and attention to detail in adolescents and adults with severe forms of anorexia nervosa

OBJECTIVE

To determine if adolescents and adults diagnosed with anorexia nervosa differ in their levels of cognitive flexibility and attention to detail independently of potential confounds.

METHOD

Sixty-two adolescents and 54 adults were assessed while receiving inpatient treatment and completed the following self-reports: Eating Disorders Examination Questionnaire, Maudsley Obsessive Compulsive Inventory and Hospital Anxiety and Depression scale. Performance-based evaluations included the Wisconsin Card Sorting Test Computerised Version, the Comprehensive Trail Making Test, the Brixton Spatial Anticipation Test, the Rey Complex Figure and the Group Embedded Figures Test.

RESULTS

Comparisons of the adolescents and adults with anorexia nervosa revealed no significant differences for any of the neuropsychological test scores even after adjusting for potential confounding factors. Neither cognitive flexibility nor attention to detail were associated with level of eating disorder symptomatology, depression, anxiety or obsessive-compulsive symptomatology. Unlike age, illness duration was found weakly associated with perseverative errors Wisconsin Card Sorting Test and with the central coherence index of the Rey Complex Figure recall condition.

CONCLUSIONS

Set-shifting and central coherence performance were independent of age, clinical symptoms severity and emotional status. Additional studies on the relationship between the duration of anorexia nervosa and neuropsychological difficulties are needed.

Cognitive flexibility, central coherence, and quality of life in anorexia nervosa

BACKGROUND

Anorexia nervosa (AN) has consistently been found to be associated with poor cognitive flexibility and central coherence. These two cognitive functions have been considered important maintenance factors in AN and are addressed by specific treatment approaches such as cognitive remediation therapy. While there is clear empirical evidence that difficulties in such cognitive functions are related to impaired daily functioning in schizophrenia and bipolar disorder, this potential association has received only little attention in AN research so far. Therefore, the aim of this study was to examine potential relationships between weak cognitive flexibility, central coherence, and poor quality of life (QoL) in AN.

METHODS

Cognitive flexibility and central coherence were measured by both neuropsychological (i.e., performance based) and self-report measures alongside with self-reported QoL in a sample of 138 adult patients with AN.

RESULTS

Self-report but not performance based measures of cognitive flexibility and central coherence were associated with QoL. Weaker cognitive flexibility and central coherence were correlated with poorer QoL. These associations were independent of comorbid depression. The link between weak central coherence and poor QoL was particularly strong in patients with the restricting subtype of AN. The link between cognitive flexibility and QoL, however, was independent of AN subtype.

CONCLUSIONS

Weak cognitive flexibility and central coherence are associated with low QoL in AN, especially in patients with the restrictive subtype. However, this relationship is dependent on the method of measurement, where self-report measures seem to be more relevant than performance based measures.

Feasibility of guided internet-based cognitive behavioral therapy for patients with anorexia nervosa

OBJECTIVE

The objective of the present study was to investigate the feasibility of guided internet cognitive behavioral therapy (ICBT) for anorexia nervosa.

METHODS

We conducted a prospective single-arm study between January 2020 and March 2021. The intervention was built using videos, web programs, and chat tools. The intervention program was largely based on metacognitive training. Participants performed the self-help program once a week for 12 consecutive weeks. The primary outcome was the global Eating Disorder Examination Questionnaire (EDE-Q) score. Secondary outcomes included clinical symptoms of eating disorders, metacognitive function, body mass index, depression, and generalized anxiety. The main statistical analysis examined whether the EDE-Q score and other outcomes at the end of the intervention differed from the baseline.

RESULTS

Fourteen participants underwent the trial treatment, and 13 completed the intervention. There was a significant reduction in the global EDE-Q score from 3.48 (SD = 1.4) to 2.54 (SD = 1.5, p = 0.02, Cohen's d = 0.75) from baseline to post-intervention. Some EDE-Q subscales and body checking questionnaire scale demonstrated statistically significant improvements, with moderate to large effect sizes. Although there was no significant improvement in body mass index, metacognitive function, or depressive symptoms, there was a significant improvement in the severity of generalized anxiety (M = -4.0, p = 0.01, Cohen's d = 0.95). No adverse events were observed.

DISCUSSION

Our findings suggest that guided ICBT for anorexia nervosa is well accepted by female patients and practical as a telemedicine approach that improves symptoms. In the future, tightly controlled randomized controlled trials should be conducted for efficacy verification.

Impact of eating disorders on paid or unpaid work participation and performance: a systematic review and meta-analysis protocol

BACKGROUND

Eating disorders (ED) can reduce quality of life by limiting participation and performance in social and occupational roles, including paid or unpaid work. The association between ED pathologies and work participation and performance must be well understood to strengthen vocational rehabilitation programmes and prevent occupational disruptions in the ED population. The aims of this study are: (1) to examine the degree of association between ED pathologies and work participation and performance in 15-year-olds and older; (2) to highlight the specific ED symptoms that are most correlated with changes in work performance and participation; (3) to compile the most common metrics and assessments used to measure work participation and performance with ED.

METHODS

Medline, Embase, CINAHL, Web of Science, PsycINFO, and Cochrane Library will be searched for observational and experimental studies that meet the following criteria: (1) a clinical sample of typical or atypical ED; (2) paid or unpaid employment or training; (3) an association between ED pathologies and work participation or performance. Unpublished data will also be examined. Title and abstract, and full-text screening will be conducted in duplicate. Risk of bias and quality of evidence assessments will be completed. A random-effect meta-analysis will be performed.

DISCUSSION

This synthesis can clarify knowledge and gaps around the impact of ED on work functioning, thereby allowing better evaluation, improvements and development of current workplace assessments, interventions, and policies.

TRIAL REGISTRATION

The registration number for this systematic review on PROSPERO is CRD42021255055.

Volume and Connectivity Differences in Brain Networks Associated with Cognitive Constructs of Binge Eating

Bulimia nervosa (BN) and binge eating disorder (BED) are characterized by episodes of eating large amounts of food while experiencing a loss of control. Recent studies suggest that the underlying causes of BN/BED consist of a complex system of environmental cues, atypical processing of food stimuli, altered behavioral responding, and structural/functional brain differences compared with healthy controls (HC). In this narrative review, we provide an integrative account of the brain networks associated with the three cognitive constructs most integral to BN and BED, namely increased reward sensitivity, decreased cognitive control, and altered negative affect and stress responding. We show altered activity in BED/BN within several brain networks, specifically in the striatum, insula, prefrontal cortex (PFC) and orbitofrontal cortex (OFC), and cingulate gyrus. Numerous key nodes in these networks also differ in volume and connectivity compared with HC. We provide suggestions for how this integration may guide future research into these brain networks and cognitive constructs.

Cognitive and Experienced Flexibility in Patients With Anorexia Nervosa and Obsessive Compulsive Disorder

OBJECTIVE

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) share a neuropsychological profile characterized by cognitive inflexibility as evident in set-shifting problems, and by strong detail focus. Clinically, both patient groups display a strong rigidity which may be explained by these neurocognitive difficulties. Cognitive inflexibility may hinder treatment uptake and help explain suboptimal treatment outcomes in both AN and OCD. This is the first study to compare clinical AN and OCD groups andto examine similarities and differences in cognitive flexibility. Specifically, this study aims to investigate neuropsychological outcomes and self-reported difficulties in both clinical groups and a control group, and explore associations between the different flexibility outcomes and illness.

METHOD

Two hundred participants (61 AN, 72 OCD and 67 HC) performed neuropsychological tasks on set-shifting abilities (Trail Making Task, Stroop color-word interference, Intradimensional-Extradimensional shift task), detail focus (Group Embedded Figures Test) and self-reported set-shifting abilities and attention to detail (DFlex).

RESULTS

Similarities between patient groups were found in terms of reduced set-shifting ability on the Trail Making Task and detail focus. Moreover, both patient groups self-reported more set-shifting problems but a less strong detail focus than HC, which in turn were not related to neuropsychological task outcomes in either of the groups. In both patient groups longer illness duration was associated to longer reaction times in the switching tasks and for both groups symptom severity was associated to higher experienced inflexibility and attention to detail.

CONCLUSION

Cognitive inflexibility processes are largely similar in patients with AN and OCD. Both patient groups report inflexibility, yet this is unrelated to neuropsychological outcomes. Illness duration seems to contribute to poorer set-shifting and higher illness severity is linked to more experienced inflexibility. Findings highlight the need for entangling different domains of cognitive flexibility and detail focus and examining self-report measures for a cohesive understanding of clinically relevant flexibility weaknesses in AN and OCD.

Clinical factors predicting impaired executive functions in eating disorders: The role of illness duration

Poor performance in executive functions is observed in individuals with eating disorders (EDs). These impairments have usually been associated with the presence of comorbid psychopathology or with higher severity of EDs. However, few studies have explored the interaction between illness duration and deficits in executive functions. The present study investigates the association between ED duration and performance in decision-making, inhibitory control, and cognitive flexibility in the anorexia nervosa restrictive subtype (AN-R), bulimic/purging subtype (AN-BP), and binge spectrum disorders (BSDs) (namely, bulimia nervosa and binge eating disorder) among 116 women with EDs compared with 123 women healthy controls (HCs). Using cumulative survival analysis, we estimated the risk of deficits related to illness duration. Predictors of executive dysfunctions were assessed by regression analysis, including as potential predictors illness duration, severity of general psychopathology, and ED symptomatology. Results showed poor decision-making and cognitive flexibility in participants with EDs compared with HCs. ED duration was associated with poor inhibitory control in the AN-BP group and poor cognitive flexibility in the BSD group. The illness duration increased the risk of presenting early deficits in executive function. In decision-making and inhibitory control, the AN-R group showed the earliest deficits, whereas in cognitive flexibility it was the BSD group. ED duration predicted impaired cognitive flexibility in the BSD group and impaired inhibitory control in the AN-BP group, whereas the severity of general psychopathological symptoms was a predictor of impaired cognitive flexibility in individuals with AN-R. These results highlight the relevance of illness duration in executive dysfunctions in EDs.

The longitudinal relationship between set-shifting at 4 years of age and eating disorder related features at 9 years of age in the general pediatric population

BACKGROUND

Individuals with anorexia nervosa (AN) tend to have rigid thoughts and behaviors regarding their body weight, body image, and eating habits. While a diagnosis of AN implies severe levels of impairment, AN traits can vary on a continuum within the population. However, little is known about how early markers of AN relate to rigid thought patterns and to what extent cognitive rigidity is already present in early childhood. We examined the association of set-shifting abilities as a measure of cognitive flexibility in preadolescents with AN-related features.

METHODS

Participants included 3,987 children participating in the Generation R Study, a Dutch population-based birth cohort. Set-shifting abilities (mother report) were assessed at 4 years of age, body mass index (BMI) was determined at 4 and 9 years and restrictive eating patterns (mother report) and body image (child report) were assessed at 9 years.

RESULTS

Lower set-shifting abilities at 4 years were associated with a lower BMI (β = -.44, p = 2.2 × 10^-4 ) in girls, and more restrictive eating (β = 0.15, p = 2.7 × 10^-6 ) in both boys and girls at 9 years of age. Moreover, set-shifting at age 4 was not associated with body image at age 9.

CONCLUSION

These findings contribute to the idea that the association between set-shifting problems and AN-related features are present early in childhood, prior to the typical range of the onset of eating disorders (EDs). Longitudinal studies that capture the peak age for the development of EDs will be important to assess whether early cognitive inflexibility is an early marker of AN.

A cross-sectional examination of executive function and its associations with grazing in persons with obesity with and without eating disorder features compared to a healthy control group

PURPOSE

The current study aimed to investigate associations between grazing and different facets of executive functioning in persons with obesity with and without significant eating disorder psychopathology, compared to a healthy-weight control group.

METHODS

Eighty-nine participants (of which 20 had obesity and marked eating disorder symptomatology, 25 had obesity but without marked eating disorder symptoms, and 44 were healthy-weight age- and sex-matched participants; N = 89; 66.3% female, age = 28.59 (8.62); 18.18-58.34 years) completed a battery of neuropsychological tests and demographic and eating disorder-related questionnaires. Poisson, Negative Binomial, and Ordinary Least Squares regressions were performed to examine group differences and the associations of grazing with executive functioning within the three groups.

RESULTS

Significantly lower inhibitory control and phonemic fluency were observed for the obesity group without ED features compared to healthy-weight controls. Increasing grazing severity was associated with improved performance in inhibitory control in both groups with obesity, and with phonemic fluency in the obesity group with marked eating disorder features.

CONCLUSION

Although there is mounting evidence that specific cognitive domains, especially inhibition, are affected in obesity, evidence of further detrimental effects of eating disorder psychopathology remains mixed; additionally, for persons with obesity, there may be a weak but positive link between executive functioning and grazing behaviour.

LEVEL OF EVIDENCE

III, comparative cross-sectional observational study with a concurrent control group.

Delineating the role of binge eating in cancer research

PURPOSE

Binge eating is defined as consumption of a large amount of food accompanied by a sense of loss of control over eating. While binge eating is associated with poor physical, behavioral, and psychosocial health, it has not been studied in cancer research. Therefore, the overarching goal of this review is to delineate the role of binge eating in cancer research and to spur new research in this area. Specifically, in this review, we outlined (1) binge eating as a possible risk factor that contributes to cancer risk, (2) how binge eating may develop after cancer diagnosis, and (3) how binge eating may be associated with health and relapse during survivorship.

CONCLUSIONS

It is critical to elucidate the role of binge eating in the prevention of cancer and long-term cancer survivorship. This review suggested a number of ways that binge eating may increase risk for cancer as well as several pathways that may lead to the development of binge eating after cancer diagnosis.

LEVEL OF EVIDENCE

Level V: narrative review.

Neuropsychological functioning in adult anorexia nervosa: A meta-analysis

Several studies have conceptualized neuropsychological dysfunction as part of the core pathology and defining behaviors seen in the eating disorder anorexia nervosa (AN). The aim of the current review was to synthesize the differences in neuropsychological test performance between individuals with AN and healthy controls, quantify and explain their heterogeneity. The search and screening procedures resulted in fifty studies that comprised 186 neuropsychological test results. Utilizing random-effects meta-analyses, the results revealed evidence for significant, moderate underperformance in people with AN in overall neuropsychological functioning (g¯ = -0.43, 95 % CI [-0.50, -0.36]). Weighted mean effect sizes ranged from g¯ = -0.53 for visuospatial abilities to g¯ = -0.10 for planning. Study and participant characteristics, including body mass index (BMI) and age, had significant moderator effects, especially on executive function, memory, and visuospatial abilities. The findings from the current study provide an extensive and comprehensive overview of the possible impairments in neuropsychological functioning in adult patients diagnosed with AN.

Understanding implicit and explicit learning in adolescents with and without anorexia nervosa

BACKGROUND

Cognitive disturbances such as impairments in learning are thought to play a role in adult Anorexia Nervosa (AN). It is remains unclear to what extent these disturbances result from starvation of the brain, or relate to an abnormal premorbid cognitive profile. This study investigates learning processes in adolescents with AN, hypothesizing that implicit learning is intact, as found previously in explicit learning tasks. Secondly, we hypothesized that anxiety and depression symptoms, inherent to AN, are associated to learning processes in AN.

METHODS

In total 46 adolescents diagnosed with AN and 44 control participants were administered an implicit category learning task in which they were asked to categorize simple perceptual stimuli (Gabor patches) based on a linear integration (i.e., an implicit task) of orientation and spatial frequency of the stimulus. A subgroup of adolescents (n = 38) also completed a task assessing explicit learning.

RESULTS

Model-based analyses indicated that adolescents with AN performed significantly more accurately compared to their healthy peers regardless of whether they used the optimal strategy or not. Depression and anxiety did not relate to learning performance in the AN group.

CONCLUSIONS

Overall, our findings of augmented implicit and explicit learning in adolescents with AN corroborate recent studies that suggested higher stimulus-response learning during prediction error paradigms. Learning disturbances in adult AN may then be at least partly due to long-term malnourishment, highlighting the importance of early recognition and refeeding in treatments for AN.

Determining the potential links of self-compassion with eating pathology and body image among women and men: A cross-sectional mediational study

This study examined whether rumination, shame, self-criticism, and perfectionism mediate the previously established link between self-compassion and both eating and body image concerns. A cross-sectional online survey was completed by a community sample of non-clinical adult women (n = 369) and men (n = 201). Participants completed standardised measures of self-compassion (predictor), rumination, external shame, perfectionism and self-criticism (mediating variables), and eating pathology and body image (criterion variables). Path analyses confirmed that higher self-compassion was serially linked to lower eating pathology and body dissatisfaction through comparative self-criticism and external shame. Compared with women, the association between higher self-compassion and lower body dissatisfaction was weaker in men. However, there were no mediating effects of rumination, perfectionism, or internalized self-criticism. Overall results indicate notable similarities between women and men, and emphasise the potential value of targeting external shame during eating disorder prevention and treatment. Longitudinal study of these constructs is warranted in future research.

Cognitive Remediation Therapy Does Not Enhance Treatment Effect in Obsessive-Compulsive Disorder and Anorexia Nervosa: A Randomized Controlled Trial

BACKGROUND

Guideline-recommended therapies are moderately successful in the treatment of obsessive-compulsive disorder (OCD) and anorexia nervosa (AN), leaving room for improvement. Cognitive inflexibility, a common trait in both disorders, is likely to prevent patients from engaging in treatment and from fully benefiting from existing therapies. Cognitive remediation therapy (CRT) is a practical augmentation intervention aimed at ameliorating this impairing cognitive style prior to disorder-specific therapy.

OBJECTIVE

To compare the effectiveness of CRT and a control treatment that was not aimed at enhancing flexibility, named specialized attention therapy (SAT), as add-ons to treatment as usual (TAU).

METHODS

In a randomized controlled multicenter clinical trial, 71 adult patients with OCD and 61 with AN were randomized to ten twice-weekly sessions with either CRT or SAT, followed by TAU. Patients were evaluated at baseline, post-CRT/SAT, and after 6 and 12 months, with outcomes being quantified using the Yale-Brown Obsessive Compulsive Scale for OCD and the Eating Disorder Examination Questionnaire for AN.

RESULTS

Across study groups, most importantly CRT+TAU was not superior to control treatment (SAT)+TAU in reducing OCD and AN pathology. Contrary to expectations, SAT+TAU may have been more effective than CRT+TAU in patients being treated for OCD.

CONCLUSIONS

CRT did not enhance the effect of TAU for OCD and AN more than SAT. Unexpectedly, SAT, the control condition, may have had an augmentation effect on TAU in OCD patients. Although this latter finding may have been due to chance, the effect of SAT delivered as a pretreatment add-on intervention for adults with OCD and AN merits future efforts at replication.

Examining the roles of emotion dysregulation and impulsivity in the relationship between psychological trauma and substance abuse among women with bulimic-spectrum pathology

Individuals with bulimia nervosa report elevated rates of childhood maltreatment, which appears to increase risk for co-occurring substance use problems and negatively impact clinical course. The current study sought to examine the mechanistic pathways by which specific forms of childhood maltreatment may give rise to substance use problems among individuals with bulimic-spectrum pathology. Women with bulimic-spectrum disorders (N = 204) completed measures of childhood trauma, emotion dysregulation, impulsivity, and substance use. Path analysis was used to examine emotion dysregulation and impulsivity as mediators of the relationship between distinct forms of childhood trauma (physical abuse, physical neglect, emotional abuse, emotional neglect, and sexual abuse) and the presence of problematic alcohol/drug use. In the full path model, significant pathways from childhood emotional abuse to emotion dysregulation, childhood emotional neglect to impulsivity, and emotion dysregulation to problematic substance use emerged. Further, emotion dysregulation significantly mediated the relationship between emotional abuse and substance use. Results indicate that emotion dysregulation may be an important mechanism linking a history of childhood emotional maltreatment to later eating and substance use problems, and therefore may be an important treatment target among individuals with co-occurring eating and substance use concerns.Childhood emotional abuse was related to greater emotion dysregulation.Childhood emotional neglect was related to greater impulsivity.Emotion dysregulation was related to greater problematic substance use.Emotional abuse may impact substance use through emotion dysregulation.Creating emotion dysregulation may improve substance and eating disorder symptoms.

Current directions in biomarkers and endophenotypes for anorexia nervosa: A scoping review

There are currently no validated biomarkers for anorexia nervosa (AN), though recent literature suggests an increased research interest in this area. Biomarkers are objective, measurable indicators of illness that can be used to assist with diagnosis, risk assessment, and tracking of illness state. Related to biomarkers are endophenotypes, which are quantifiable phenomena that are distinct from symptoms and which link genes to manifest illness. In this scoping review, we sought to provide a summary of recent research conducted in the pursuit of biomarkers and endophenotypes for AN. The findings indicate that a number of possible biomarkers which can assess the presence or severity of AN independently of weight status, including psychophysical (e.g., eye-tracking) and biological (e.g., immune, endocrine, metabolomic, neurobiological) markers, are currently under investigation. However, this research is still in early phases and lacking in replication studies. Endophenotype research has largely been confined to the study of several neurocognitive features, with mixed evidence to support their classification as possible endophenotypes for the disorder. The study of biomarkers and endophenotypes in AN involves significant challenges due to confounding factors of illness-related sequalae, such as starvation. Future research in these areas must prioritise direct evaluation of the sensitivity, specificity and test-retest reliability of proposed biomarkers and enhanced control of confounding physical consequences of AN in the study of biomarkers and endophenotypes.

Clinical and Cognitive Functioning Changes After Partial Hospitalization in Patients With Anorexia Nervosa

Introduction: Anorexia nervosa is usually associated with emotional and cognitive difficulties. Little knowledge is available about the changes in cognitive functioning in patients undergoing treatments. The aim of the present study was to longitudinally assess the impact of partial hospitalization on clinical and cognitive functioning in anorexia nervosa. Materials and Methods: 56 women with anorexia nervosa according to DSM-5 criteria and 58 healthy women were enrolled in the study. At baseline, all participants underwent clinical, diagnostic and neuropsychological assessment (T0). Patients were also assessed at the end of the treatment program (T1; n = 56). Results: BMI improved significantly throughout treatment. At baseline, patients showed significantly poorer executive abilities and less specific autobiographical memory. After the day-hospital program, decision-making abilities improved significantly. Response to treatment was predicted by BMI at admission and duration of illness, but neuropsychological performance did not contribute to the prediction model. Discussion: Cognitive difficulties, mostly regarding executive functions, resulted differently affected by clinical improvement. In particular, while cognitive monitoring and cognitive inhibition appear to be mostly stable trait-like characteristics, decision-making is both more state-dependent and sensitive to clinical status. None of the cognitive variables added information about the response to day hospital treatment; patients with short duration of illness and a rapidly decreasing BMI would benefit more from intensive interventions than less "acute" patients. These observations, if confirmed by future studies, have important clinical implications in order to understand the impact of malnutrition on cognitive functioning and to provide individualized effective treatment for patients with anorexia nervosa.