A systematic review and meta-analysis of set-shifting ability in eating disorders

Are you how you eat? Aspects of self-awareness in eating disorders

Eating disorders (ED) are severe psychiatric disorders characterized by dysfunctional behaviors related to eating or weight control, with profound impacts on health, quality of life, and the financial burden of affected individuals and society at large. Given that these disorders involve disturbances in self-perception, it is crucial to comprehend the role of self-awareness in their prevalence and maintenance. This literature review presents different self-awareness processes, discussing their functioning across different levels of complexity. By deconstructing this concept, we can gain a better understanding of how each facet of self and personality relates to the symptoms of these disorders. Understanding the absence or impairment of self-awareness in ED holds significant implications for diagnosis, treatment, and overall management. By recognizing and comprehending the characteristics of self-awareness, clinicians can develop tailored interventions and evidence-based treatments for individuals with ED. Furthermore, this narrative review underscores the importance of considering temperament and personality factors in the context of ED, as temperament traits and personality characteristics may interact with self-awareness processes, influencing the development and maintenance of ED. Ultimately, the results highlight the pressing need for further research on the development of effective interventions and support strategies grounded in the aspects of self-awareness mechanisms for individuals affected by these disorders.

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.

Cognitive inflexibility and heightened error monitoring are related to lower sexual functioning

Sexual functioning is an important predictor of well-being and relationship satisfaction. Previous research indicates that several aspects of cognitive function are related to sex-related behaviors and functioning among individuals with sex-related disorders, neurological disorders, and in older adults; however, this has been relatively underexamined in younger populations. To examine this, the present study assessed whether behavioral and/or neurophysiological measures of cognitive function are associated with sexual functioning in a community sample of young 489 adults (64 % female) ages 18-30. Cognitive flexibility (n = 460) and inhibition (n = 466) were measured using neuropsychological assessment (D-KEFS), and conflict monitoring and error monitoring were measured by event-related potentials (conflict N2: n = 394; error-related negativity: n = 389). After separately testing relations between the different measures of cognitive function and sexual functioning, we assessed whether results (1) remained after covarying for externalizing and internalizing dimensions (PID-5; n = 489) or (2) varied by gender. Finally, we tested whether any aspects of cognitive function were unique predictors of sexual functioning. Cognitive flexibility and error monitoring (i.e., error-related negativity) were both significantly related to sexual functioning among males and females, such that poorer cognitive flexibility and heightened error monitoring were related to lower sexual functioning. No significant effects emerged for inhibition or conflict monitoring. In a multiple regression model, cognitive flexibility and error monitoring each accounted for a unique portion of variance in sexual functioning beyond other aspects of cognitive function and psychopathology-related traits. Results suggest that cognitive function is a meaningful correlate of sexual functioning in young adulthood, which should be considered further in future research.

Prospective associations between cognitive flexibility and eating disorder symptoms in anorexia nervosa and bulimia nervosa

This study investigated concurrent and prospective associations between measures of reversal learning and attentional set-shifting and eating disorder symptoms at baseline, 3 months, and 6 months among individuals with anorexia nervosa restricting subtype (AN-R, n = 26), AN binge eating/purging subtype (AN-BP, n = 22), bulimia nervosa (BN, n = 35), and healthy controls (n = 27), and explored whether these associations differed by diagnosis. At baseline, participants completed diagnostic interviews, height/weight measurements, and measures of set-shifting (the Intradimensional/Extradimensional shift task) and reversal learning (a probabilistic reversal learning task). At 3- and 6-month follow-up, participants with eating disorders completed assessments of weight and eating disorder symptoms. A one-way analysis of variance found no evidence that baseline reversal learning and attentional set-shifting differed across diagnostic groups. Multilevel modeling analyses indicated that perseverative errors (an index of reversal learning) predicted an increase in purging over time for individuals with AN-BP and BN. Set-shifting errors differentially predicted frequency of loss of control eating for individuals with AN-BP and BN; however, set-shifting was not related to loss of control eating when examined separately in AN-BP and BN. These findings suggest that disentangling facets of cognitive flexibility may help understand change in eating disorder symptoms.

The impact of continuous calorie restriction and fasting on cognition in adults without eating disorders

Research into the effects of calorie restriction continues to intrigue those interested in whether it may allow humans to live longer and healthier lives. Animal studies of continuous calorie restriction (CCR) and fasting have demonstrated substantial advantages to health and longevity. However, concerns remain about the impact of restricting calorie intake on human health and cognition. Given the emerging evidence of cognitive impairments in eating disorders, studies investigating restricted calorie intake in healthy humans (in an ethical way) may also have implications for understanding restrictive eating disorders. In this review, the published literature on the impact of CCR and fasting on cognitive function in healthy human participants is synthesized. Of the 33 studies of CCR and fasting in humans identified, 23 demonstrated significant changes in cognition. Despite variation across the cognitive domains, results suggest CCR benefits inhibition, processing speed, and working memory, but may lead to impairments in cognitive flexibility. The results of fasting studies suggest fasting is associated with impairments in cognitive flexibility and psychomotor abilities. Overall, the results of these studies suggest the degree (ie, the severity) of calorie restriction is what most likely predicts cognitive improvements as opposed to impairments. For individuals engaging in sustained restriction, this may have serious, irreversible consequences. However, there are mixed findings regarding the impact of CCR and fasting on this aspect of human functioning, suggesting further research is required to understand the costs and benefits of different types of calorie restriction.

Family accommodation in PTSD: Proposed considerations and distinctions from the established transdiagnostic literature

Accommodation is widely documented and studied among internalizing disorders; however, the conceptualization and study of accommodation in the context of posttraumatic stress disorder (PTSD) is relatively nascent. PTSD entails many diagnostic criteria-including exposure to a distinct Criterion A event, emotional numbing, and anger-that may uniquely influence accommodation and merit special consideration. Our aim was to review the impact of accommodation in PTSD, compare and contrast accommodation in PTSD to other disorders with a strong empirical evidence base regarding accommodation, and highlight considerations unique to PTSD and associated implications for accommodation. We conclude by providing considerations for future research and practice.

Adaptive learning from outcome contingencies in eating-disorder risk groups

Eating disorders are characterised by altered eating patterns alongside overvaluation of body weight or shape, and have relatively low rates of successful treatment and recovery. Notably, cognitive inflexibility has been implicated in both the development and maintenance of eating disorders, and understanding the reasons for this inflexibility might indicate avenues for treatment development. We therefore investigate one potential cause of this inflexibility: an inability to adjust learning when outcome contingencies change. We recruited (n = 82) three groups of participants: those who had recovered from anorexia nervosa (RA), those who had high levels of eating disorder symptoms but no formal diagnosis (EA), and control participants (HC). They performed a reinforcement learning task (alongside eye-tracking) in which the volatility of wins and losses was independently manipulated. We predicted that both the RA and EA groups would adjust their learning rates less than the control participants. Unexpectedly, the RA group showed elevated adjustment of learning rates for both win and loss outcomes compared to control participants. The RA group also showed increased pupil dilation to stable wins and reduced pupil dilation to stable losses. Their learning rate adjustment was associated with the difference between their pupil dilation to volatile vs. stable wins. In conclusion, we find evidence that learning rate adjustment is unexpectedly higher in those who have recovered from anorexia nervosa, indicating that the relationship between eating disorders and cognitive inflexibility may be complex. Given our findings, investigation of noradrenergic agents may be valuable in the field of eating disorders.

Measuring implicit associations between food and body stimuli in anorexia nervosa: a Go/No-Go Association Task

PURPOSE

The present study aimed to explore the implicit associations between food and bodily stimuli in patients with anorexia nervosa (AN) and control subjects (HC).

METHODS

A Go/No-Go Association Task was administrated to 55 participants (28 AN and 27 HC), using food stimuli (low-calorie food vs. high-calorie food) and body stimuli (underweight vs. overweight bodies).

RESULTS

We evidenced an implicit association between food and body stimuli in the AN group, whereas the HC group only showed a tendency. AN and HC groups also exhibited different categorization strategies: the AN group tended to categorize stimuli as low-calorie foods and underweight bodies less than the HC group, and they tended to categorize stimuli as high-calorie foods and overweight bodies more than the HC group.

CONCLUSION

The present study revealed for the first time specificities of the AN population's implicit association between food and body stimuli in terms of association strength and categorization strategy. Furthermore, the results suggest that combining implicit methodologies with other methods could contribute to a better characterization of the physiopathology of AN.

LEVEL OF EVIDENCE

Level I, experimental study.

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.

Exploring the role of autistic traits and eating disorder psychopathology on mentalising ability in the general population

BACKGROUND

This study evaluated the role of overlapping traits and characteristics related to autism spectrum disorder (autism) and anorexia nervosa (AN) in the general population, and the impact of these traits on mentalising ability.

METHODS

A sample of young adults (N = 306), aged 18-25 years, was recruited to complete an online study that consisted of 4 measures: the Autism-Spectrum Quotient, Eating Disorder Examination Questionnaire, the Mentalization Scale, and the Reading the Mind in the Eyes task.

RESULTS

Higher levels of autistic traits, particularly difficulty with attention switching, were associated with increased eating disorder psychopathology. Overall, autistic traits and eating disorder psychopathology were related among females, but not males. Difficulty with attention switching, however, was related to eating disorder psychopathology among both females and males. Autistic traits also appear to have a greater role in mentalising ability than does eating disorder psychopathology.

CONCLUSION

The role of attention switching in overlapping traits of autism and eating disorder psychopathology needs to be more comprehensively evaluated by future research, as does the role of biological sex. Expanded knowledge in this field will help to better understand and evaluate symptoms at presentation, leading to clearer diagnoses and potentially better treatment outcomes.

Specific psychological therapies versus other therapies or no treatment for severe and enduring anorexia nervosa

BACKGROUND

Anorexia nervosa is a psychological condition characterised by self-starvation and fear or wait gain or other body image disturbance. The first line of treatment is specific psychological therapy; however, there is no consensus on best practice for treating people who develop severe and enduring anorexia nervosa (SEAN). Notably, there is no universal definition of SEAN.

OBJECTIVES

To evaluate the benefits and harms of specific psychological therapies for severe and enduring anorexia nervosa compared with other specific therapies, non-specific therapies, no treatment/waiting list, antidepressant medication, dietary counselling alone, or treatment as usual.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The last search date was 22 July 2022.

SELECTION CRITERIA

We included parallel randomised controlled trials (RCTs) of people (any age) with anorexia nervosa of at least three years' duration. Eligible experimental interventions were any specific psychological therapy for improved physical and psychological health in anorexia nervosa, conducted in any treatment setting with no restrictions in terms of number of sessions, modality, or duration of therapy. Eligible comparator interventions included any other specific psychological therapy for anorexia nervosa, non-specific psychological therapy for mental health disorders, no treatment or waiting list, antipsychotic treatment (with or without psychological therapy), antidepressant treatment (with or without psychological therapy), dietary counselling, and treatment as usual as defined by the individual trials.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were clinical improvement (weight restoration to within the normal weight range for participant sample) and treatment non-completion. Results were presented using the GRADE appraisal tool.

MAIN RESULTS

We found two eligible studies, but only one study provided usable data. This was a parallel-group RCT of 63 adults with SEAN who had an illness duration of at least seven years. The trial compared outpatient cognitive behaviour therapy for SEAN (CBT-SEAN) with specialist supportive clinical management for SEAN (SSCM-SE) over eight months. It is unclear if there is any difference between the effect of CBT-SEAN versus SSCM-SE on clinical improvement at 12 months (risk ratio (RR) 1.42, 95% confidence interval (CI) 0.66 to 3.05) or treatment non-completion (RR 1.72, 95% CI 0.45 to 6.59). There were no reported data on adverse effects. The trial was at high risk of performance and detection bias. We rated the GRADE level of evidence as very low-certainty for both primary outcomes, downgrading for imprecision and risk of bias concerns.

AUTHORS' CONCLUSIONS

This review reports evidence from one trial that evaluated CBT-SEAN versus SSCM-SE. There was very low-certainty evidence of little or no difference in clinical improvement and treatment non-completion between the two therapies. There is a need for larger high-quality trials to determine the benefits of specific psychological therapies for people with SEAN. These should take into account the duration of illness as well as participants' previous experience with evidence-based psychological therapy for anorexia nervosa.

Cognitive and Interpersonal Factors in Adolescent Inpatients with Anorexia Nervosa: A Network Analysis

The cognitive-interpersonal model of anorexia nervosa (AN) posits that cognitive and interpersonal traits contribute to the development and maintenance of AN. We investigated cognitive and interpersonal factors put forward by the model in a sample of 145 adolescent inpatients with AN using network analysis. Our main outcomes included core eating disorder symptoms, cognitive style, socio-affective factors, and mood symptoms. We estimated a cross-sectional network using graphical LASSO. Core and bridge symptoms were identified using strength centrality. Goldbricker was used to reduce topological overlap. The node with the highest strength centrality was Concern over Mistakes, followed by Eating Preoccupation, Social Fear, and Overvaluation of Weight and Shape. The nodes with the highest bridge strength were Concern over Mistakes, Doubt about Actions, Overvaluation of Weight and Shape, and Depression. Notably, both performance on a cognitive flexibility task and BMI were not connected to any other nodes and were subsequently removed from the final network. We provide partial support for the cognitive-interpersonal model while also supporting certain premises put forward by the transdiagnostic cognitive-behavioral model. The high centrality of Concern over Mistakes and Social Fear supports the theory that both cognitive and interpersonal difficulties contribute to AN, particularly in adolescence.

Temporal dynamics of cognitive flexibility in adolescents with anorexia nervosa: A high-density EEG study

Impairment in cognitive flexibility is a core symptom of anorexia nervosa (AN) and is associated with treatment resistance. Nevertheless, studies on the neural basis of cognitive flexibility in adolescent AN are rare. This study aimed to investigate brain networks underlying cognitive flexibility in adolescents with AN. To address this aim, participants performed a Dimensional Change Card Sorting task during high-density electroencephalography (EEG) recording. Anxiety was measured with the State-Trait Anxiety Inventory. Data were collected on 22 girls with AN and 23 controls. Evoked responses were investigated using global-spatial analysis. Adolescents with AN showed greater overall accuracy, fewer switch trial errors and reduced inverse efficiency switch cost relative to controls, although these effects disappeared after adjusting for trait and state anxiety. EEG results indicated augmented early visual orienting processing (P100) and subsequent impaired attentional mechanisms to task switching (P300b) in subjects with AN. During task switching, diminished activations in subjects with AN were identified in the posterior cingulate, calcarine sulcus and cerebellum, and task repetitions induced diminished activations in a network involving the medial prefrontal cortex, and several posterior regions, compared with controls. No significant associations were found between measures of cognitive flexibility and anxiety in the AN group. Findings of this study suggest atypical neural mechanisms underlying cognitive flexibility in adolescents with AN. More importantly, our findings suggest that different behavioural profiles in AN could relate to differences in anxiety levels. Future research should investigate the efficacy of cognitive training to rebalance brain networks of cognitive flexibility in AN.

Executive dysfunction in eating disorders: Relationship with clinical features

Eating disorders (ED) are severe mental disorders that may result in significant functional impairment and disability. Neuropsychological studies have consistently found impaired executive function (EF) among ED patients. EF is particularly involved in fundamental skills of daily living and in behavioral and emotional regulation. In this study, impairment of executive functioning is investigated in patients with eating disorders and the associations with clinical features and clinical subtypes are analyzed.

METHOD

75 female patients (m = 22.01 years, sd = 9.15) with eating disorder (43 restrictive anorexia, 30 binge-eating anorexia and 13 bulimia nervosa) and 37 healthy controls (m = 18.54 years, sd = 4.21) were included in the study. An extensive assessment of executive function domains (verbal fluency, set shifting, attention span, selective attention, working memory, inhibitory control and processing speed) was carried out in both groups. Clinical scales for food intake restriction, binge-eating/purging, depression, anxiety and impulsivity were also administered and correlated with scores on executive function tests.

RESULTS

Patients with an ED had significantly lower scores than healthy controls in performance of several executive function tests, particularly in set shifting, interference control and processing speed (p < .01, in all three domains). Executive function impairment was related to anxious, depressive and eating disorder symptoms (p < .05), regardless of clinical subtype.

CONCLUSIONS

Executive function impairment in eating disorders is associated with greater ED symptomatic severity and might involve a negative treatment outcome. Therefore, cognitive remediation techniques should probably be considered in a number of severe patients with ED.

Neurocognitive Endophenotypes for Eating Disorders: A Preliminary High-Risk Family Study

Eating disorders (EDs) are psychiatric disorders with a neurobiological basis. ED-specific neuropsychological and brain characteristics have been identified, but often in individuals in the acute phase or recovered from EDs, precluding an understanding of whether they are correlates and scars of EDs vs. predisposing factors. Although familial high-risk (FHR) studies are available across other disorders, this study design has not been used in EDs. We carried out the first FMH study in EDs, investigating healthy offspring of women with EDs and controls. We preliminarily aimed to investigate ED-related neurocognitive and brain markers that could point to predisposing factors for ED. Sixteen girls at FHR for EDs and twenty control girls (age range: 8−15), completed neuropsychological tests assessing executive functions. Girls also underwent a resting-state fMRI scan to quantify functional connectivity (FC) within resting-state networks. Girls at FHR for EDs performed worse on a cognitive flexibility task compared with controls (F = 5.53, p = 0.02). Moreover, they showed different FC compared with controls in several resting-state networks (p < 0.05 FDR-corrected). Differences identified in cognitive flexibility and in FC are in line with those identified in individuals with EDs, strongly pointing to a role as potential endophenotypes of EDs.

Altered processing of conflicting body representations in women with restrictive anorexia nervosa

Cognitive and affective impairments in processing body image have been observed in patients with Anorexia Nervosa (AN) and may induce the hypercontrolled and regulative behaviors observed in this disorder. Here, we aimed to probe the link between activation of body representations and cognitive control by investigating the ability to resolve body-related representational conflicts in women with restrictive AN and matched healthy controls (HC). Participants performed a modified version of the Flanker task in which underweight and overweight body images were presented as targets and distractors; a classic version of the task, with letters, was also administered as a control. The findings indicated that performance was better among the HC group in the task with bodies compared to the task with letters; however, no such facilitation was observed in AN patients, whose overall performance was poorer than that of the HC group in both tasks. In the task with body stimuli, performance among patients with AN was the worst on trials presenting underweight targets with overweight bodies as flankers. These results may reflect a dysfunctional association between the processing of body-related representations and cognitive control mechanisms that may aid clinicians in the development of optimal individualized treatments.

Altered Reinforcement Learning from Reward and Punishment in Anorexia Nervosa: Evidence from Computational Modeling

OBJECTIVES

Anorexia nervosa (AN) is associated with altered sensitivity to reward and punishment. Few studies have investigated whether this results in aberrant learning. The ability to learn from rewarding and aversive experiences is essential for flexibly adapting to changing environments, yet individuals with AN tend to demonstrate cognitive inflexibility, difficulty set-shifting and altered decision-making. Deficient reinforcement learning may contribute to repeated engagement in maladaptive behavior.

METHODS

This study investigated learning in AN using a probabilistic associative learning task that separated learning of stimuli via reward from learning via punishment. Forty-two individuals with Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 restricting-type AN were compared to 38 healthy controls (HCs). We applied computational models of reinforcement learning to assess group differences in learning, thought to be driven by violations in expectations, or prediction errors (PEs). Linear regression analyses examined whether learning parameters predicted BMI at discharge.

RESULTS

AN had lower learning rates than HC following both positive and negative PE (p < .02), and were less likely to exploit what they had learned. Negative PE on punishment trials predicted lower discharge BMI (p < .001), suggesting individuals with more negative expectancies about avoiding punishment had the poorest outcome.

CONCLUSIONS

This is the first study to show lower rates of learning in AN following both positive and negative outcomes, with worse punishment learning predicting less weight gain. An inability to modify expectations about avoiding punishment might explain persistence of restricted eating despite negative consequences, and suggests that treatments that modify negative expectancy might be effective in reducing food avoidance in AN.

Evaluating thinking styles in adults with an eating disorder: Associations with life satisfaction, psychological symptoms, and treatment engagement

Cognitive weaknesses have been implicated as a vulnerability factor in the development and maintenance of eating disorders. Despite this, cognitive styles are not routinely assessed in adult outpatient eating disorder programs and little is known about how they may impact patients' functional outcomes, psychological symptoms, or treatment engagement. The aim of this study was to evaluate thinking styles (i.e., cognitive rigidity and attention to detail) among adults attending specialized outpatient treatment for an eating disorder and assess whether such styles were associated with participants' satisfaction with life, psychological symptoms, and engagement in the outpatient group therapy program. Demographic and physical health information was collected from 95 adults who were eligible for an outpatient program. Participants completed the Detail and Flexibility Questionnaire, Satisfaction with Life Scale, Beck Depression Inventory second edition, and Beck Anxiety Inventory. Elevated scores for cognitive rigidity and attention to detail were transdiagnostic rather than specific to eating disorder diagnoses. Cognitive rigidity and attention to detail were associated with lower satisfaction with life, and increased anxiety and depression. Cognitive styles of cognitive rigidity and attention to detail were not associated with engagement in treatment or treatment completion. Cognitive patterns may be important for clinicians to evaluate as part of routine outpatient care given that they occur transdiagnostically and are linked with psychological symptoms and functional outcomes for adults struggling with an eating disorder.

Group cognitive remediation therapy for children and adolescents in intensive day-patient treatment for anorexia nervosa: a feasibility study

Background

Cognitive Remediation Therapy (CRT) is an adjunct treatment targeting set-shifting (SS) and weak central coherence (CC) thought to play a role in maintaining anorexia nervosa (AN). This study aimed to test the feasibility of brief group CRT for young people with AN in a day-patient setting using neuropsychological assessment of SS and CC. It also explored the benefit for young people with Autism Spectrum Disorder (ASD) features.

Methods

Twenty female day-patients (12–18 years) with AN or Atypical AN completed neuropsychological assessment of SS (using the Wisconsin Card Sorting Task and the Brixton Spatial Anticipation Test) and of CC (using the Rey Osterrieth Complex Figures Task) pre and post 4 sessions of group CRT. Baseline ASD features and weight change pre and post were measured. Feasibility was assessed regarding the recruitment process, intervention feedback, suitability of neuropsychological assessment measures, and effect sizes.

Results

Study uptake was 95%, intervention retention was 91%, and group CRT was rated as acceptable. Medium to large effect size improvements were found across measures of SS (d_z = 0.44 to d_z = 0.90) and medium size improvements found in CC (d_z = 0.59). Young people with ASD features showed smaller to similar size improvements in SS and larger improvements in CC. There was a moderate (not significant) correlation with level of weight restoration.

Conclusions

Important study parameters have been estimated in order to plan a future definitive trial of brief group CRT in a day-patient setting using neuropsychological assessment. These findings also have implications for the use of brief group CRT in young people with ASD features.

A network approach can improve eating disorder conceptualization and treatment

Eating disorders are severe mental illnesses with the second highest mortality rate of all psychiatric illnesses. Eating disorders are exceedingly deadly because of their complexity. Specifically, eating disorders are highly comorbid with other psychiatric illnesses (up to 95% of individuals with an eating disorder have at least one additional psychiatric illness), have extremely heterogeneous presentations, and individuals often migrate from one specific eating disorder diagnosis to another. In this Perspective, we propose that understanding eating disorder comorbidity and heterogeneity via a network theory approach offers substantial benefits for both conceptualization and treatment. Such a conceptualization, strongly based on theory, can identify specific pathways that maintain psychiatric comorbidity, how diagnoses vary across individuals, and how specific symptoms and comorbidities maintain illness for one individual, thereby paving the way for personalized treatment.

Relationships between executive functions and food rejection dispositions in young children

This study examined the associations between the two main kinds of food rejection, neophobia and pickiness, and executive functions in young children. Caregivers of children (n = 240) aged 3-6 years completed measures of their children's food neophobia and pickiness. A battery of tests measured children's executive functions and world knowledge. Children with higher levels of neophobia and pickiness had lower cognitive flexibility scores than children with lower levels of food rejection. Moreover, the association between food neophobia and cognitive flexibility was stronger than the association between food pickiness and cognitive flexibility. Working memory, inhibition, and world knowledge were not related to children's food rejection. These findings unraveled for the first time the negative relationship between cognitive flexibility and the main psychological barriers to dietary variety. These results contribute to a better understanding of the set of cognitive factors that are associated with food rejection in young children.

Eating disorders and autism spectrum: links and risks

In the last decades, increasing attention has been provided to socio-cultural and neurobiological factors involved in the psychopathology of feeding and eating disorders (FED), encouraging a multifactorial approach. In this framework, several authors stressed an association between FED and other kinds of psychiatric disorders from both a psychopathological and a neurobiological point of view. In particular, many promising contributions are focusing on the possible link between FED and autism spectrum disorder (ASD). Growing interest about this association rose from the frequently reported evidence of ASD-like traits amongst FED patients and abnormal eating behaviors amongst patients with ASD. This narrative review overview aims to summarize the most relevant findings about the overlap between different kinds of FED and the autism spectrum, taking into account the most recent hypotheses about the psychopathology of both these conditions. While most of the studies focused on anorexia nervosa, both ASD and autistic traits seem to be detectable also in other kinds of FED. In addition, the recently increased interest toward a dimensional approach to psychopathology led to progressively broadening the concept of ASD, focusing on its subthreshold and gender-specific manifestations and on its link with other psychiatric conditions, including FED. Globally the studies summarized here provide further support to theoretical models featuring a neurodevelopmental approach for mental disorders. In particular, FED have been conceptualized as a possible psychopathological trajectory of a neurodevelopmental alteration, toward which female gender would act as one of many predisposing factors.

Cognitive and quality-of-life related factors of body mass index (BMI) improvement after deep brain stimulation in the subcallosal cingulate and nucleus accumbens in treatment-refractory chronic anorexia nervosa

BACKGROUND

Up to 20% of the cases of anorexia nervosa (AN) are chronic and treatment-resistant. Recently, the efficacy of deep brain stimulation (DBS) for severe cases of AN has been explored, with studies showing an improvement in body mass index and other psychiatric outcomes. While the effects of DBS on cognitive domains have been studied in patients with other neurological and psychiatric conditions so far, no evidence has been gathered in AN.

METHODS

Eight patients with severe, chronic, treatment-resistant AN received DBS either to the nucleus accumbens (NAcc) or subcallosal cingulate (SCC; four subjects on each target). A comprehensive battery of neuropsychological and clinical outcomes was used before and 6-month after surgery.

FINDINGS

Although Body Mass Index (BMI) did not normalise, statistically significant improvements in BMI, quality of life, and performance on cognitive flexibility were observed after 6 months of DBS. Changes in BMI were related to a decrease in depressive symptoms and an improvement in memory functioning.

INTERPRETATION

These findings, although preliminary, support the use of DBS in AN, pointing to its safety, even for cognitive functioning; improvements of cognitive flexibility are reported. DBS seems to exert changes on cognition and mood that accompany BMI increments. Further studies are needed better to determine the impact of DBS on cognitive functions.

Anorexia Nervosa, Body Image Perception and Virtual Reality Therapeutic Applications: State of the Art and Operational Proposal

Anorexia Nervosa (AN) patients exhibit distorted body representation. The purpose of this study was to explore studies that analyze virtual reality (VR) applications, related to body image issues, to propose a new tool in this field. We conducted a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, EMBASE, Scopus, and Web of Science databases were explored; the review included 25 studies. Research has increased over the last five years. The selected studies, clinical observational studies (n = 16), mostly concerning patients' population with AN (n = 14) or eating disorders (EDs) diagnosis, presented multiple designs, populations involved, and procedures. Some of these studies included healthy control groups (n = 7). Studies on community sample populations were also selected if oriented toward clinical applications (n = 9). The VR technologies in the examined period (about 20 years) have evolved significantly, going from very complex and bulky systems, requiring very powerful computers, to agile systems. The advent of low-cost VR devices has given a big boost to research works. Moreover, the operational proposal that emerges from this work supports the use of biofeedback techniques aimed at evaluating the results of therapeutic interventions in the treatment of adolescent patients diagnosed with AN.

Inhibition and shifting across the weight status spectrum

Executive functioning (EF) is of major interest in the study of cognitive factors involved in obesity. Among EF, shifting is related to behavioral flexibility, and inhibition to the ability to refrain from impulsive behavior. A deficit in those two EF could predict individual difficulties to maintain a healthy lifestyle. Weak evidence of deficits in shifting and inhibition in individuals of higher Body Mass Index (BMI) have been observed. The objective was to clarify the relationship between inhibition and shifting regarding weight status group differences in healthy adults. Two neuropsychological tests from the Test of Attentional Performance (TAP) battery were used to measure EF performance of three groups of men and women: normal-weight (NW, n = 38), overweight (OW, n = 40) and obesity (OB, n = 37). The results show that individuals with higher BMI have lower inhibition capacities and that classically used weight status categories might not capture cognitive variability. No differences in shifting were observed concerning weight status nor BMI. This paper provides new insights on cognitive factors in obesity by presenting data from healthy individuals with overweight and obesity. The results support that assessing inhibition capacities might be of interest in a clinical setting for patients with difficulties to lose weight.

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.

Validity and utility of Hierarchical Taxonomy of Psychopathology (HiTOP): III. Emotional dysfunction superspectrum

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a quantitative nosological system that addresses shortcomings of traditional mental disorder diagnoses, including arbitrary boundaries between psychopathology and normality, frequent disorder co-occurrence, substantial heterogeneity within disorders, and diagnostic unreliability over time and across clinicians. This paper reviews evidence on the validity and utility of the internalizing and somatoform spectra of HiTOP, which together provide support for an emotional dysfunction superspectrum. These spectra are composed of homogeneous symptom and maladaptive trait dimensions currently subsumed within multiple diagnostic classes, including depressive, anxiety, trauma-related, eating, bipolar, and somatic symptom disorders, as well as sexual dysfunction and aspects of personality disorders. Dimensions falling within the emotional dysfunction superspectrum are broadly linked to individual differences in negative affect/neuroticism. Extensive evidence establishes that dimensions falling within the superspectrum share genetic diatheses, environmental risk factors, cognitive and affective difficulties, neural substrates and biomarkers, childhood temperamental antecedents, and treatment response. The structure of these validators mirrors the quantitative structure of the superspectrum, with some correlates more specific to internalizing or somatoform conditions, and others common to both, thereby underlining the hierarchical structure of the domain. Compared to traditional diagnoses, the internalizing and somatoform spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and greater clinical applicability. Validated measures are currently available to implement the HiTOP system in practice, which can make diagnostic classification more useful, both in research and in the clinic.

The obsessive-compulsive spectrum: A network analysis

Several studies have shown that obsessive-compulsive disorder (OCD), eating disorders (ED), autism spectrum disorders (ASD) and body dysmorphic disorder (BDD) share obsessive-compulsive (OC) symptoms and often co-occur, which could be seen as indicative of a common etiological basis. In addition, they also appear to have similarities in executive functioning. The present study investigated disorder-specific symptoms and executive functioning as a possible joint factor in individuals with OCD (n=53), BDD (n=95), ED (n=171) and ASD (n=73), and in healthy controls (n=110). The participants completed online questionnaires measuring OCD, ED, ASD and BDD related symptoms as well as executive functioning. The clinical groups were first compared to the healthy controls. Subsequently, a network analysis was performed only with the OC-groups. This network approach assumes that psychopathological disorders are the result of causal symptom interactions. As expected, the healthy controls reported less severe symptoms compared to the OC patient groups. The network analysis suggested that the executive functioning skill set shifting/attention switching and the ASD symptoms, social and communication skills were the most central nodes in the model. Difficulty with cognitive flexibility and social factors are central in OC-spectrum disorders and may be perpetuating factors and thus a relevant focus of treatment.

How Does Fasting Affect Cognition? An Updated Systematic Review (2013-2020)

PURPOSE OF REVIEW

The goal of this review was to provide an update on the literature examining how voluntary, temporary abstention from eating impacts cognitive function.

RECENT FINDINGS

We evaluated peer-reviewed articles published between August 2013 and January 2021 that assessed adults, included a measure of cognitive functioning with neutral stimuli, and compared individuals in a fasted state to individuals in a fed state (either within- or between-subject designs). Nineteen articles (21 studies) met inclusion criteria. Sample sizes, fasting methods, and tasks varied across studies. Review of studies indicated that fasting was associated with deficits in cognitive functioning; few studies indicated a benefit in cognitive functioning following a single voluntary fast. The heterogeneity and rarity of available studies limits the conclusions that can be drawn. Several crucial psychosocial and sociodemographic moderators remain unexplored. Recommendations for future work are discussed.

An eye-tracking study examining the relationship between males' eating disorder symptomatology, body mass index, and expectations about character behaviour in text

Eating disorder prevalence is increasing in males, perhaps more rapidly than in females. Theorists have proposed that cognitive biases are important factors underpinning disordered eating, especially those related to food, body, and perfectionism. We investigated these factors in relation to males' eating disorder symptomatology in the general population by using eye-tracking during reading as a novel and implicit measure. 180 males' eye movements were monitored while they read scenarios (third-person in Experiment 1 (n = 90, 18-38(M_age = 21.50, SD = 3.65)); second-person in Experiment 2 (n = 90, 18-35(M_age = 20.50, SD = 2.22))) describing characters' emotional responses (e.g. upset) to food-, body image-, and perfectionism-related events. Participants' eating disorder symptomatology was then assessed, and body mass index (BMI) was calculated. Results showed processing of characters' emotional responses (detected via eye-tracking) to body- and perfectionism-related events for third-person scenarios was related to eating disorder symptomatology. Processing of characters' emotional responses to body-related events for second-person scenarios was related to males' BMI. The moment-to-moment processing of characters' emotional responses to food-related scenarios was not related to eating disorder symptomatology or BMI. Findings support theories that include body- and perfectionism-related cognitive biases as underlying mechanisms of eating disorder symptomatology and the use of implicit measures of cognitive processes underlying males' eating disorder symptomatology.

Impulsivity and compulsivity in binge eating disorder: A systematic review of behavioral studies

BACKGROUND

Binge eating disorder (BED) often includes impulsive and compulsive behaviors related to eating behavior and food. Impulsivity and compulsivity generally may contribute to the etiology and maintenance of multiple psychiatric disorders including BED. This review aimed to identify and synthesize available behavioral studies of impulsivity and compulsivity among individuals with BED.

METHOD

A systematic search was performed focusing on BED and specific facets of impulsivity (rapid response and choice) and compulsivity (set-shifting, cognitive flexibility, and/or habit learning). All case-control studies comparing adults with either full-threshold or subthreshold BED to individuals with normal weight, overweight/obesity, or other eating disorders (e.g., bulimia nervosa) were included.

RESULTS

Thirty-two studies representing 29 unique samples met inclusion criteria. Increased choice impulsivity was observed among individuals with BED relative to individuals with normal weight. There were mixed findings and/or a lack of available evidence regarding rapid response impulsivity and compulsivity. The presence of between-group differences was not dependent on sample characteristics (e.g., full or sub threshold BED diagnosis, or treatment-seeking status). Heterogeneity relating to covariates, task methodologies, and power limited conclusions.

CONCLUSIONS

Literature supports a postive association between choice impulsivity and BED. More research is needed to determine if individuals with BED demonstrate elevated levels of either rapid response impulsivity or types of compulsivity. Careful selection of covariates and consideration of task methodologies and power would aid future research.

The Neuropsychological Profile of Severe and Enduring Anorexia Nervosa: A Systematic Review

Characteristics of Severe and Enduring Anorexia Nervosa (SE-AN) are being investigated to differentiate the patients experiencing SE-AN from those at earlier stages of the AN disease. The current systematic review was the first step in exploring neuropsychological functioning as a potentially identifying characteristic for long-term presentations. With a subgroup of AN patients reflecting a unique neuropsychological profile that is proportionate to the quantity of patients that go on to develop SE-AN, it was the aim of this review to assess neuropsychological functioning in the later stage of the disease. In accordance with PRISMA guidelines, a literature search was conducted using four electronic databases (PsycINFO, MEDLINE, Web of Science, and Scopus) for neuropsychological research on AN participants with a seven or more year illness duration. Datasets that met inclusion criteria were screened for SE-AN participants (N = 166) and neuropsychological data extracted together with potentially confounding variables and information required to conduct a quality assessment. In research investigating decision-making, participants with a SE-AN presentation demonstrated significantly lower functioning compared to healthy controls. There was conflicting evidence for differences in intellectual functioning and set-shifting abilities with no variability indicated in central coherence, memory, attention, reasoning, or processing speed. If findings from this preliminary analysis are confirmed through empirical research, implications include earlier identification of SE-AN patients and more effective treatment development.

Structural and functional brain alterations in anorexia nervosa:A multimodal meta-analysis of neuroimaging studies

Anorexia nervosa (AN) is a complex psychiatric disorder with poorly understood etiology. Numerous voxel‐based morphometry (VBM) and resting‐state functional imaging studies have provided strong evidence of abnormal brain structure and intrinsic and functional activities in AN, but with inconsistent conclusions. Herein, a whole‐brain meta‐analysis was conducted on VBM (660 patients with AN, and 740 controls) and resting‐state functional imaging (425 patients with AN, and 461 controls) studies that measured differences in the gray matter volume (GMV) and intrinsic functional activity between patients with AN and healthy controls (HCs). Overall, patients with AN displayed decreased GMV in the bilateral median cingulate cortex (extending to the bilateral anterior and posterior cingulate cortex), and left middle occipital gyrus (extending to the left inferior parietal lobe). In resting‐state functional imaging studies, patients with AN displayed decreased resting‐state functional activity in the bilateral anterior cingulate cortex and bilateral median cingulate cortex, and increased resting‐state functional activity in the right parahippocampal gyrus. This multimodal meta‐analysis identified reductions of gray matter and functional activity in the anterior and median cingulate in patients with AN, which contributes to further understanding of the pathophysiology of AN.

Cognitive rigidity and heightened attention to detail occur transdiagnostically in adolescents with eating disorders

Cognitive inflexibility and attention to detail bias represent a promising target in eating disorder (ED) treatment. While prior research has found that adults with eating disorders exhibit significant cognitive inflexibility and heightened attention to detail, less is known about these cognitive impairments among adolescents, and across EDs transdiagnostically. To address this gap, adolescent females (N = 143) from a residential ED program with anorexia nervosa, bulimia nervosa, or other specified feeding or eating disorder completed the Detail and Flexibility Questionnaire (DFlex) and measures of ED and general psychopathology. Transdiagnostically, adolescents with EDs scored higher than an archival sample of healthy control adolescents on both cognitive rigidity (p < .001; Cohen's d = 1.92) and attention to detail (p < .001; Cohen's d = 1.16). These cognitive impairments were significantly associated with severity of eating pathology, and these relationships existed independent of age, duration of illness, or body mass index (BMI). Our findings suggest cognitive inflexibility and heightened attention to detail occur transdiagnostically in adolescents with eating disorders and are unlikely to be a scar of the disorder. Future prospective research is needed to determine whether these cognitive styles represent an endophenotype of eating disorders.

Same room - different windows? A systematic review and meta-analysis of the relationship between self-report and neuropsychological tests of cognitive flexibility in healthy adults

Cognitive flexibility can be thought of as the ability to effectively adapt one's cognitive and behavioural strategies in response to changing task or environmental demands. To substantiate the common inference that self-report and neuropsychological tests of cognitive flexibility provide 'different windows into the same room', we undertook a systematic review and meta-analysis to determine whether self-report and neuropsychological tests of cognitive flexibility are related in healthy adults. Ten databases and relevant grey literature were searched from inception. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were adhered to. Twenty-one articles satisfied our inclusion criteria. A multi-level random-effects meta-analysis revealed no relationship (0.05, 95% CI = -0.00 to 0.10). Random-effects meta-analyses raised the possibility that the Cognitive Flexibility Scale and the Trail Making Test - part B (time) may be related (0.19, 95% CI = 0.06 to 0.31). We conclude that the relationship between self-report and neuropsychological tests of cognitive flexibility is not large enough to be considered convincing evidence for the two assessment approaches sharing construct validity. These results have clear implications for assessing and interpreting cognitive flexibility research and clinical practice.

Is poor global processing a transdiagnostic feature of Body Dysmorphic Disorder and Anorexia Nervosa? A meta-analysis

Body dysmorphic disorder (BDD) and anorexia nervosa (AN) are characterised by body image disturbance. It has been suggested that poor global integration in visual processing may underlie distorted body image, but empirical studies have yielded mixed results. The current study involved two meta-analyses aimed at examining the extent to which poor global processing is evident in BDD and AN. Studies were identified through a systematic literature search up to October 2020. The BDD search yielded 16 studies and the AN search yielded 18 studies. Random-effect models demonstrated a small pooled effect size for BDD (g = -0.44, 95 % CI -0.70, -0.17, p < 0.001) and a moderate pooled effect size for AN (g = -0.63, 95 % CI -0.77, -0.49, p <  .001), with no evidence of significant publication bias for either. The results provide evidence that poor global processing is a transdiagnostic feature of both BDD and AN, although effects may be more pronounced in AN. Our findings highlight the possibility that interventions aimed at promoting global visual processing could prove beneficial in disorders characterised by distorted body image.

Hunger games: Associations between core eating disorder symptoms and responses to rejection by peers during competition

OBJECTIVE

Individuals with eating disorder (ED) symptoms are sensitive to social threat and report maladaptive interpersonal styles that may contribute to and exacerbate negative evaluation from others. Research in this area has relied primarily on self-report. The current study examined associations between behavioral responses to social threat and core ED symptoms using a behavioral paradigm. Based on previous findings that individuals with binge-eating report being more reactive and confrontational, whereas individuals with dietary restriction tend to be more submissive and avoidant of conflict, we hypothesized that binge eating would be associated with a greater tendency to retaliate against rejection perpetrators, whereas dietary restriction would be associated with a lower tendency to retaliate when rejected.

METHOD

Undergraduate women (N = 132) completed a self-report measure of ED symptoms and participated in an online "Survivor"-type game in which they voted to either accept or reject computerized coplayers, while also receiving acceptance or rejection feedback from others.

RESULTS

Neither ED symptom was associated with how often participants retaliated against coplayers who rejected them. However, dietary restriction was related to more rejection votes overall (i.e., the tendency to reject others regardless of how others voted).

DISCUSSION

Findings suggest that individuals with dietary restriction may rely on a maladaptive defensive strategy aimed at pre-empting rejection, or alternatively, have difficulty shifting from habitual self-isolating behavior that results from over-involvement with restricting symptoms. Interventions targeting hypersensitivity to social threat or interpersonal flexibility may help reduce interpersonal stress and mitigate its impact on restricting symptoms.

Lower pattern recognition memory scores in anorexia nervosa

BACKGROUND

There is extensive evidence for volumetric reductions in the hippocampus in patients with anorexia nervosa (AN), however the impact on function is unclear. Pattern separation and recognition are hippocampus-dependent forms of learning thought to underlie stimulus discrimination.

METHODS

The present study used the Mnemonic Similarity Task to investigate pattern separation and recognition for the first time in patients with AN (N = 46) and healthy controls (N = 56). An Analysis of Covariance examined between-group differences, controlling for age, antidepressant use and method of task delivery (remote vs. in person).

RESULTS

When controlling for covariates, pattern recognition memory scores were lower in the AN group with a medium effect size (d = 0.51). In contrast, there was a small effect whereby patients with AN had a greater pattern separation score than controls (d = 0.34), albeit this difference was not significant at the p = 0.05 threshold (p = 0.133). Furthermore, pattern separation and recognition memory abilities were not related to age, body mass index, eating disorder psychopathology or trait anxiety levels.

CONCLUSIONS

This preliminary study provides initial evidence for an imbalance in pattern separation and recognition abilities in AN, a hippocampus-dependent cognitive ability. Further studies should endeavour to investigate pattern separation and recognition performance further in AN, as well as investigate other hippocampus-dependent functions.

Increased cognitive flexibility mediates the improvement of eating disorders symptoms, depressive symptoms and level of daily life functioning in patients with anorexia nervosa treated in specialised centres

OBJECTIVE

Poor cognitive flexibility has been highlighted in patients with anorexia nervosa (AN), contributing to the development and maintenance of symptoms. The aim of the present study is to investigate how enhanced cognitive flexibility is involved in treatment outcomes in patients with AN.

METHOD

One hundred thirty female out-patients treated for AN have been assessed at baseline and after 4 months of treatment. Path analyses were used to investigate the mediating role of cognitive flexibility, measured through the Brixton test, on a wide range of outcomes: body mass index, eating disorder symptoms, daily life functioning, anxiety, depression, emotions, self-rated silhouette.

RESULTS

Cognitive flexibility was improved during treatment, and enhanced cognitive flexibility explains a significant part of level of the improvement in daily life functioning (26%), reduction of eating disorder symptoms (18%) and reduction of depressive symptoms (17%). Others outcomes were also improved, but these improvements were not mediated by cognitive flexibility.

CONCLUSIONS

Results suggest that enhancing cognitive flexibility could help reduce rigid cognitive and behavioural patterns involved in AN, thus improving everyday functioning and clinical severity. Further studies combining different types of cognitive flexibility evaluation as well as neuroimaging may be necessary to better establish which of its aspects are involved in patients' improvement.

Conducting a Pilot Randomized Controlled Trial on a Medical Inpatient Unit Utilizing Cognitive Remediation Therapy for Adolescents with Restrictive Eating Disorders: Protocol Updates and Reflections on Feasibility

We conducted a pilot randomized control trial (RCT) to simultaneously examine the feasibility of effectively implementing Cognitive Remediation Therapy (CRT) for adolescents with anorexia nervosa (AN) during medical hospitalization at a single-site hospital center. Employment of this protocol occurred on a general medical unit with diverse medical admitting diagnoses, not an eating disorder floor of a hospital and not part of a structured inpatient anorexia nervosa treatment program. This was the first time an RCT for a psychosocial intervention was implemented on this unit with patients with eating disorders. Here, we describe the process of piloting the study, including modifications that needed to be made to the original protocol. We also describe the feedback from major stakeholders regarding the process of conducting the pilot study. We summarize lessons learned and steps to take for smooth integration of an RCT of a therapeutic intervention on medical unit.Trial registration: ClinicalTrials.gov Identifier NCT02883413.

The shifting perspectives study protocol: Cognitive remediation therapy as an adjunctive treatment to family based treatment for adolescents with anorexia nervosa

BACKGROUND

Adolescents with anorexia nervosa have set-shifting inefficiencies that can be exacerbated by starvation and that may interfere with outcomes of treatment interventions. Cognitive Remediation Therapy (CRT), an adjunctive treatment focused on improving set-shifting, can target inefficiencies and may augment treatment effectiveness. The best way to add CRT to the standard of care (Family Based Treatment, FBT) for adolescents with anorexia remains understudied.

METHODS/DESIGN

This is a randomized controlled trial designed to determine if CRT is effective in increasing flexibility in adolescents with anorexia and/or their parents. Participants are adolescents 12-18 years old with anorexia and their parents. 54 family groups will be randomized into one of three groups: FBT only, FBT plus Parent-focused CRT, or FBT plus Adolescent-focused CRT. Psychosocial, neurocognitive, and behavioral measures will be collected throughout the study.

DISCUSSION

This is the first study of its kind to apply CRT to parents. All forms of CRT in the context of anorexia have targeted the individual with anorexia's thinking style. We propose that it may be impactful to target the parent of the adolescent with anorexia as parents carry the burden of treatment and re-nourishment of their child during FBT and may have similar thinking styles.

CONCLUSION

This study takes an experimental therapeutics approach to further our understanding of the mechanisms of treatment for adolescents with anorexia. It focuses on increasing cognitive flexibility in patients or their parents and determining the appropriate dose of CRT needed to achieve positive change.

TRIAL REGISTRATION

ClinicalTrails.gov Identifier NCT03928028.

The C Factor: Cognitive dysfunction as a transdiagnostic dimension in psychopathology

Research into cognitive functions across psychological disorders suggests that cognitive deficiencies may be present across multiple disorders, potentially pointing to a transdiagnostic phenomenon. More recently, a single dimension model of psychopathology, the p factor, has been proposed, in which cognitive deficits are thought to be an intrinsic construct, assumed to be transdiagnostic. However, no systematic investigation to date tested this hypothesis. The aim of the present study was to systematically review meta-analyses to assess the hypothesis that the C factor (cognitive dysfunction) is transdiagnostic in psychopathology and review potential moderators that may account for such a phenomenon. We conducted a systematic review of meta-analyses examining cognitive function across all disorders for which data were available. Included meta-analyses (n = 82), comprising 97 clinical samples, yielded 1,055 effect sizes. Twelve major disorders/categories (e.g., bipolar disorder, substance use disorders) were included, comprising 29 distinct clinical entities (e.g., euthymic bipolar disorder; alcohol use disorder). Results show that all disorders reviewed are associated with underperformance across cognitive domains, supporting the hypothesis that the C factor (or cognitive dysfunction) is a transdiagnostic factor related to p. To examine moderators that may explain or contribute to c, we first consider important interpretative limitations of neuropsychological data in psychopathology. More crucially, we review oft-neglected motivational and emotional transdiagnostic constructs of p, as prominent contributing constructs to the C factor. These constructs are offered as a roadmap for future research examining these constructs related to p, that contribute, and may account for cognitive dysfunctions in psychopathology.

Central coherence and set-shifting between nonunderweight eating disorders and anorexia nervosa: A systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis compared previously documented inefficiencies in central coherence and set-shifting between people with nonunderweight eating disorders (bulimia nervosa and binge-eating disorder) and people with anorexia nervosa.

METHOD

We performed random-effects meta-analyses on 16 studies (1,112 participants) for central coherence and 38 studies (3,505 participants) for set-shifting. Random effects meta-regressions were used to test whether the effect sizes for people with nonunderweight eating disorders were significantly different from the effect sizes for people with anorexia nervosa.

RESULTS

People with anorexia nervosa (Hedge's g = -0.53, 95% CIs: -0.80, -0.27, p < .001) and bulimia nervosa (Hedge's g = -0.70, 95% CIs: -1.14, -0.25, p = .002), but not binge-eating disorder, had significantly poorer central coherence than healthy controls. Similarly, people with anorexia nervosa (Hedge's g = -0.38, 95% CIs: -0.50, -0.26, p < .001) and bulimia nervosa (Hedge's g = -0.55, 95% CIs: -0.81, -0.29, p < .001), but not binge-eating disorder, had significantly poorer set-shifting than healthy controls. The effect sizes for people with nonunderweight eating disorders did not significantly differ from those for people with anorexia nervosa.

DISCUSSION

Our meta-analysis was underpowered to make definitive judgments about people with binge-eating disorder. However, we found that people with bulimia nervosa clearly have central coherence and set-shifting inefficiencies which do not significantly differ from those observed in people with anorexia nervosa. Clinically, this suggests that people with bulimia nervosa might benefit from adjunctive approaches to address these inefficiencies, such as cognitive remediation therapy.

Caregiver Report of Executive Functioning in Adolescent Females With Anorexia Nervosa or Autism Spectrum Disorder

Current literature suggesting a shared endophenotype between individuals with anorexia nervosa (AN) and autism spectrum disorder (ASD) related to executive functioning (EF) has several limitations: performance-based instead of ecologically valid measures of set-shifting are used, lack of comparisons between same-sex groups, and reliance on adult samples only. This was the first study directly comparing female youth with ASD to female youth with AN using an ecologically valid measure of EF. A secondary data analysis combined caregiver-reported EF on the Behavior Rating Inventory of Executive Functioning (BRIEF) for 22 female adolescent youth with AN and 29 female adolescent youth with ASD. EF in each group was compared to population norms, and EF was compared between groups. Compared to population norms, adolescents with AN had elevated scores on shift, initiate, and emotional control scales, and adolescents with ASD had elevated scores on all scales of the BRIEF and were more likely to have scores in the clinical range. There were significant differences between groups on all but three scales. The cognitive profiles and clinical scores of AN females were not comparable to those of ASD females. The findings reveal a clear clinical impairment in females with ASD but not in females with AN. The results do not support the hypothesis of similar real-world EF profiles between these groups. The results encourage further exploration into the similarities and distinctions between these two disorders.

Cognitive and emotional regulation in adolescents and young women with eating disorders

BACKGROUND

Eating disorders (EDs) are associated with a reduced ability to regulate emotion and impulses during the life span. Working memory and executive functions (EFs) are cognitive regulatory systems supported by networks involving the pre-frontal cortex. Studies in EDs found impaired functioning in these domains, showing an association between EDs and the reduced ability to control emotions and impulses.

OBJECTIVE

To investigate EF in adolescents and young women with eating disorders (ED) using a quasi-experimental design, focusing on cognitive efficiency, emotional regulation (ER) and behavioural outcomes also taking into account pharmacological treatment and duration of illness.

METHODS

A sample of 151 females belonging to two groups took part in this study. Twenty-six girls and young women (M_age 22;8 years) with ED and 125 typically developed girls and young women (M_age 17;4 years) completed a battery of cognitive tasks (Go-no-go, Stop-signal task, Symmetry span, Reading Span) and the Youth Self-Report and the Difficulties in Emotional Regulation Scale Performance. A series of ANOVA with the Brown-Forsythe test was used to compare the groups.

RESULTS

Participants with ED and controls did not show significant differences in EF tasks, whereas differences between younger and older participants with ED emerged. Moreover, ER difficulties seem to be associated with mainly internalizing problems in EDs. Further analysis on the full ED sample did not reveal any significant differences associated with the disorder persistence. Considering pharmacological treatment effects over cognitive, emotional and behavioural measures emerged.

CONCLUSIONS

The present study documented no specific differences in EF between control and participants with EDs, whereas important differences emerged in ER and behavioural outcomes perception in the clinical sample, together with a partial influence of pharmacological treatment.

LEVEL OF EVIDENCE

No level of evidence.

The Role of Disgust in Eating Disorders

PURPOSE OF REVIEW

In current review, we evaluate the current literature examining the role of disgust in eating disorders (EDs), and provide a theoretical model designed to inform the study and treatment of disgust-based symptoms in EDs.

RECENT FINDINGS

Findings from this review suggest that aberrant disgust-conditioning processes represent promising but understudied mechanisms that may contribute to the risk and maintenance of core eating disorder (ED) psychopathology. In addition, preliminary evidence supports the use of interventions designed to target aversive disgust cues and disrupt maladaptive disgust-based conditioning that may maintain eating pathology. However, experimental studies designed to elucidate the role of disgust and aversive learning processes remain limited. Disgust is a promising risk and maintenance factor in EDs. Future systematic investigation is needed to examine disgust-based processes at a mechanistic level in order to better understand the links between disgust, avoidance behaviors, and EDs. Further investigation of the mechanistic role of disgust in EDs is warranted.

Drunkorexia: An Examination of the Role of Theory of Mind and Emotional Awareness among Adolescents

This study aimed to investigate Theory of Mind (ToM) and emotional awareness in drunkorexia, an emerging behavior characterized by calorie restriction when drinking alcohol is planned. A sample of 246 adolescents (148 females, 98 males; range 17-20) completed self-reported measures assessing drunkorexia, ToM and lack of emotional awareness. Drunkorexia was negatively correlated with ToM abilities, with reading neutral emotions, and positively with lack of emotional awareness. ToM and lack of emotional awareness were also found to predict drunkorexia. Findings highlighted that adolescents who engage in drunkorexia may have difficulties in reading others' mental states and being aware of their emotions.

Toward a Computational Neuropsychology of Cognitive Flexibility

Cognitive inflexibility is a well-documented, yet non-specific corollary of many neurological diseases. Computational modeling of covert cognitive processes supporting cognitive flexibility may provide progress toward nosologically specific aspects of cognitive inflexibility. We review computational models of the Wisconsin Card Sorting Test (WCST), which represents a gold standard for the clinical assessment of cognitive flexibility. A parallel reinforcement-learning (RL) model provides the best conceptualization of individual trial-by-trial WCST responses among all models considered. Clinical applications of the parallel RL model suggest that patients with Parkinson's disease (PD) and patients with amyotrophic lateral sclerosis (ALS) share a non-specific covert cognitive symptom: bradyphrenia. Impaired stimulus-response learning appears to occur specifically in patients with PD, whereas haphazard responding seems to occur specifically in patients with ALS. Computational modeling hence possesses the potential to reveal nosologically specific profiles of covert cognitive symptoms, which remain undetectable by traditionally applied behavioral methods. The present review exemplifies how computational neuropsychology may advance the assessment of cognitive flexibility. We discuss implications for neuropsychological assessment and directions for future research.