Set-shifting, central coherence and decision-making in individuals recovered from anorexia nervosa: a systematic review

A cluster-randomised controlled feasibility trial evaluating the Cognitive Occupation-Based programme for people with Multiple Sclerosis (COB-MS)

INTRODUCTION

There is a high prevalence of cognitive difficulties in MS, but despite this, there are few programmes targeting cognition that focus on the ability to function well in everyday life. The Cognitive Occupation-Based programme for people with Multiple Sclerosis (COB-MS), an occupation-focused cognitive intervention, was developed to address this. It addresses both the functional difficulties and the wide-ranging symptoms that present in MS.

OBJECTIVE

Here we report on the results of a cluster-randomised controlled feasibility trial (ISRCTN11462710; registered 4th September 2019) evaluating the COB-MS in terms of feasibility and initial efficacy as a cognitive intervention for people with MS.

METHOD

The eight-session COB-MS intervention was delivered remotely by occupational therapists to participants with MS in the intervention group. Following the end of the trial the COB-MS was delivered to the wait-list control group. Data was collected from people with MS experiencing cognitive difficulties at baseline, post-intervention, 12-weeks, and 6-month follow-up. The primary outcome measure was the Goal Attainment Scaling at 12 weeks. Data was also collected in the domains of cognition, quality of life, and mood.

RESULTS

One hundred and eighteen people with MS and cognitive difficulties were randomised to either usual care (n = 60) or COB-MS intervention (n = 58). Ninety-four participants were retained at 6-month follow-up. The COB-MS was found to be feasible, including trial procedures and protocol. Data indicates that the COB-MS is accepted by participants and had positive impacts on daily life. Those allocated to the COB-MS group had a significant improvement in the primary outcome compared to the control condition. Progression criteria set for the feasibility trial have been met therefore further testing of the COB-MS at a definitive trial is supported by the results.

CONCLUSION

The results provide a strong basis for a pathway to a future definitive trial of COB-MS, with respect to both feasibility and preliminary, clinical efficacy.

TRIAL REGISTRATION

ISRCTN11462710 Date of registration: 4th September 2019.

A Systematic Review to Explore a Neuropsychological Profile that Predates Anorexia Nervosa

OBJECTIVE

Research demonstrates reduced cognitive flexibility and weak central coherence during acute illness and following recovery from anorexia nervosa (AN). This systematic review investigated if these impairments are present in first-degree relatives of individuals with AN, representing a possible neuropsychological risk profile.

METHODS

A systematic review of electronic databases was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search ended on July 14, 2023. Established search terms and inclusion criteria identified relevant research. Risk of bias was assessed using the Critical Appraisal Skills Program. The review was registered with Prospero international prospective register of systematic reviews (No. CRD42023401268). Study selection, descriptive data, critical appraisal, and risk of bias are presented in tables and figures.

RESULTS

The search yielded 10 studies. The included studies conducted neuropsychological assessments of discordant AN relatives and lifetime longitudinal study participants. Most studies found cognitive flexibility and central coherence to be significantly reduced in participants with AN and their relatives compared with controls. One study found decision making to be significantly impaired in AN participants and relatives. Effect sizes were moderate to large.

DISCUSSION

Reduced cognitive flexibility and weak central coherence appear to be endophenotypes of AN. Further research is required with relatives concordant for AN to establish whether these biomarkers co-segregate with AN within families. These findings suggest a possibility of developing screeners to identify individuals at risk of AN allowing for early intervention.

Social Cognition, Executive Functioning, Mood, and Disability in Cervical Dystonia

BACKGROUND

Individuals with idiopathic adult-onset isolated cervical dystonia (CD) may have cognitive difficulties and increased mood challenges. Social cognition and executive functioning may be particularly affected.

OBJECTIVE

To explore social cognition and executive functioning performance in individuals with CD, using the Cambridge Neuropsychological Test Automated Battery (CANTAB), as previous research has used traditional, nondigital neuropsychological assessments. We sought to investigate the relationships between social cognition, executive functioning, mood, and disability in individuals with CD.

METHODS

We recruited 37 individuals with CD, including 26 women with an age range of 33 to 69 years (M = 56.64, SD = 8.31) from a dystonia clinic in a hospital neurology department. The individuals completed selected tasks from the CANTAB measuring social cognition and executive functioning. We compared the individuals' performance with CANTAB normative data. Depression, anxiety, disease severity, and disability were measured.

RESULTS

The individuals with CD had significantly lower scores than the CANTAB normative data in both social cognition and executive functioning tasks, with the largest differences evident in problem-solving, attention, and positive emotion bias tasks. Poorer emotion recognition was associated with increased difficulties in problem-solving tasks. The individuals demonstrated a bias toward identifying happiness in facial affect, which was related to a poorer recognition of emotions. Cognitive performance was not related to CD severity or disability or to current mood symptoms.

CONCLUSION

Difficulties with both social cognition and executive functioning were identified in the individuals with CD, and are likely important targets for clinical interventions.

No Evidence for Cross-Sectional or Longitudinal Associations between Cognitive Flexibility Performances and Nutritional Status in a Cohort of Inpatients with Anorexia Nervosa

BACKGROUND

According to the Cognitive-Interpersonal model of anorexia nervosa (AN), the combined influence of cognitive and socio-emotional difficulties would constitute vulnerability and maintaining factors. Poor cognitive flexibility is one of the endophenotypic candidates (i.e., a trait marker) of the disorder, but few studies have examined its association with illness symptom variations, notably weight status. The study aimed to evaluate the relationships between cognitive flexibility performances and nutritional status indices (BMI; body composition) at different times of the disorder.

METHODS

Cross-sectional and longitudinal associations between cognitive flexibility (TAP 2.1) and nutritional status indices, along with anxious and depressive (HAD) and eating disorder (EDE-Q) symptomatology were investigated using univariate and multivariate analyses in a cohort of AN inpatients evaluated at hospital admission (N = 167) and discharge (N = 94).

RESULTS

We found no or negligible associations between nutritional status and HAD or EDE-Q scores or cognitive flexibility performances, either cross-sectionally or longitudinally. Cognitive performances did not significantly differ between the AN subtypes.

CONCLUSIONS

In agreement with the Cognitive-Interpersonal model of AN, cognitive flexibility is independent of nutritional status, as well as the AN subtype. It is also independent of the levels of anxious, depressive, or ED symptomatology. A new therapeutic approach targeting cognitive flexibility and intolerance to change could benefit severely emaciated people with AN, regardless of disease subtype and level of dysphoria.

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.

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 flexibility in women who recovered from anorexia nervosa - a model-based approach

Research findings on cognitive flexibility (CF) functioning in women who recovered from anorexia nervosa (RAN) were found to be inconsistent. This was attributed to the multiple definitions of CF and the diverse measuring tools used to assess it. Applying a deductive approach to explore CF function may address these inconsistencies; thus, we used a model that divides CF into three subtypes, namely, stimulus-response mapping, switching sets and task switching. Additionally, we explored the association between CF subtypes and the disorder's clinical measures to assess the relation of CF to recovery. Forty-three RAN and 54 healthy controls performed tasks designed to assess CF subtypes based on the model's division, and the RAN group completed the Eating Disorder Examination Questionnaire. The results showed that the RAN group performed significantly worse than controls only in the stimulus-response mapping subtype. Additionally, there were no correlations between CF subtypes and clinical symptoms or the disorder measures - current and nadir body mass index, age of onset, time since recovery, and disorder duration. In conclusion, the study revealed CF impairment after recovery from AN, specifically in stimulus-response mapping. The variability in performance of the CF subtypes supports the application of a theory-driven perspective viewing CF as a modular ability in RAN. Additionally, CF is unrelated to clinical measures post-recovery and thus may not be used as a criterion for evaluating recovery.

[Medical complications in anorexia and bulimia nervosa]

Anorexia nervosa and bulimia nervosa are eating disorders associated with life-threatening multisystemic medical complications. This narrative review aimed to present the medical complications most related to these disorders. In anorexia nervosa, many of them are linked to malnutrition and underweight, usually reversible with renutrition and weight restoration, although refeeding can also be linked to some medical complications. Purging behaviors observed in the anorexia nervosa binge-purging subtype and bulimia nervosa have been mainly related to hydrolectrolyte and acid-base disturbances, in addition to local complications. Thus, an early identification and therapeutic intervention of these disorders is considered crucial. Integral medical monitoring should be ensured to prevent potential serious complications from the early stages, with the involvement of physicians, psychologists, nutritionists, and other specialists in a multidisciplinary approach according to the patient's needs.

The Efficacy of Cognitive Remediation Therapy for Anorexia Nervosa: A Systematic Review of Systematic Reviews

BACKGROUND

Cognitive remediation therapy (CRT) for anorexia nervosa (AN) is an intervention specifically focused on addressing cognitive difficulties associated with the eating disorder. This systematic review of systematic reviews and meta-analysis aimed to provide a summary of the existing literature examining the efficacy of CRT in improving the neuropsychological, psychological, and clinical parameters of patients with AN.

METHODS

Systematic reviews and meta-analyses were sought in electronic databases, encompassing studies that explored the impact of CRT on AN. Three eligible reviews were identified based on the inclusion criteria. The Revised Assessment of Multiple SysTemAtic Reviews (R-AMSTAR) was employed to evaluate the methodological quality of the reviews, and all included reviews demonstrated satisfactory methodological quality with an R-AMSTAR score of ≥22. Relevant information was extracted from each review and qualitatively compiled.

RESULTS

Findings suggest that CRT can help people increase their awareness of cognitive styles and information processing and have a positive effect on patients' responses to treatment.

CONCLUSIONS

Further research is required to better understand its impact on other relevant outcomes, including psychological variables, to optimize the treatment's benefits.

Anorexia nervosa through the lens of a severe and enduring experience: 'lost in a big world'

BACKGROUND

Severe and enduring anorexia nervosa (SE-AN), is a serious and persistent illness, despite 'state of the art' treatment. Criteria have been theoretically proposed, but not tested, and may not adequately capture illness complexity, which potentially inhibits treatment refinements. The clinical reality of death as an outcome for some people who experience SE-AN (1 in 20) and broadening access to voluntary assisted dying, further complicates the field, which is undeveloped regarding more fundamental concepts such as nosology, treatment, recovery definitions and alternative conceptualisations of SE-AN. The present paper is in response to this and aims to build upon qualitative literature to enhance phenomenological understandings of fatal SE-AN.

METHOD

A published book, being the legacy of a 32-year-old professional artist offers a rich account of a life lived with AN, for 18 years with continuous treatment. A polysemous narrative via the interrelationship between the languages of the artist's words and visual art is translated via interpretative phenomenological analysis (IPA), offering rich insight into the SE-AN experience.

FINDINGS

The process of analysis induced three superordinate themes (1) Disappearing Self (2) Dialectical Dilemma (3) Death and Dying: Finding Meaning. Two cross cutting themes traversed these themes: (a) Colour and (b) Shifting Hope, where the former produced a visual representation via the 'SE-AN Kaleidoscope'. Collectively the themes produce a concept of SE-AN, grounded in the data and depicted visually through the artist's paintings.

CONCLUSIONS

The picture of SE-AN revealed in the analysis extends upon conceptualisations of SE-AN, highlighting key processes which are thus far under explored. These factors are implicated in illness persistence eliciting opportunities for further research testing including diagnostic considerations and treatment directions. In SE-AN, distorted body image extends to a global distortion in the perception of self. Additional criteria for the severe and enduring stages of illness related to (1) self and identity processes (2) measures of 'global impoverishment' across life domains are proposed for consideration in the future testing of putative defining features of SE-AN.

Excitatory and inhibitory neurometabolites in anorexia nervosa: A systematic review of proton magnetic resonance spectroscopy studies

The dysregulation of excitatory and inhibitory neurotransmission is considered a pathological marker of Anorexia Nervosa (AN), however, no systematic evaluation of the proton Magnetic Resonance Spectroscopy (1H-MRS) literature has been conducted to date. Accordingly, we conducted a systematic review of neurometabolite differences between individuals with AN and healthy controls (HC). A comprehensive database search (until June 2023) identified seven studies meeting inclusion criteria. Samples included adolescents and adults with similar mean age (AN: 22.20 HC: 22.60), and female percentages (AN: 98%; HC: 94%). The review found a considerable need for improving study design and the reporting of MRS sequence parameters and analysis. Reduced glutamate concentrations in the ACC and OCC, and reduced Glx concentrations in the ACC were reported by one and two studies, respectively. Lastly, only one study to date has quantified GABA concentrations, with no significant differences found. In conclusion, there is currently insufficient evidence of excitatory and inhibitory neurometabolites changes in AN. As the 1H-MRS literature in AN increases, the key questions herein proposed must be revisited.

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.

The neural correlates of socio-cognitive factors and eating disorders in young people: A systematic review

BACKGROUND

Although the primary aetiology of Eating Disorders (ED) remains unknown, research suggests a complex interplay of biological, psychological, and cultural/environmental factors. This paper aims to systematically review the literature on neuroimaging studies that measure socio-cognitive factors, in the context of body dissatisfaction and EDs in young people. Specifically, our aim was to identify patterns in the findings linked to social media-type behaviours.

METHODS

The review was conducted in accordance with PRISMA guidelines using PubMed, Scopus, and Web of Science databases. 799 papers were identified in the database search and 38 studies were selected based on exclusion and inclusion criteria. Selected studies were assessed using the National Institute of Health study quality assessment tool.

RESULTS

Findings point to state-related impairments in inhibitory control and salient emotional processing. Anorexia Nervosa(AN) showed impaired set-shifting abilities, working memory and decision making, while altered activation in attention networks and associated difficulties with conflict resolution were seen for Bulimia Nervosa(BN) and Other Specified Feeding and Eating Disorders(OSFED). AN and BN also demonstrated altered sensitivity to food-related stimuli in striatal regions, suggesting aberrant top-down emotional-cognitive control. ED participants also show deficits in body representation, impaired control over social behaviours and altered integration of visual and body perception.

DISCUSSION

These findings support the notion that socio-cognitive dysfunctions in ED are underpinned by a distributed network of structural and functional brain changes which influence the way young people with ED interact with and respond to social media, and ultimately places at them at increased risk for body image disturbances. This Review was registered with the PROSPERO International Register of Systematic Reviews, Registration number CRD42021270696.

State or trait: the neurobiology of anorexia nervosa - contributions of a functional magnetic resonance imaging study

BACKGROUND

The understanding of the cerebral neurobiology of anorexia nervosa (AN) with respect to state- versus trait-related abnormalities is limited. There is evidence of restitution of structural brain alterations with clinical remission. However, with regard to functional brain abnormalities, this issue has not yet been clarified.

METHODS

We compared women with AN (n = 31), well-recovered female participants (REC) (n = 18) and non-patients (NP) (n = 27) cross-sectionally. Functional magnetic resonance imaging was performed to compare neural responses to food versus non-food images. Additionally, affective ratings were assessed.

RESULTS

Functional responses and affective ratings did not differ between REC and NP, even when applying lenient thresholds for the comparison of neural responses. Comparing REC and AN, the latter showed lower valence and higher arousal ratings for food stimuli, and neural responses differed with lenient thresholds in an occipital region.

CONCLUSIONS

The data are in line with some previous findings and suggest restitution of cerebral function with clinical recovery. Furthermore, affective ratings did not differ from NP. These results need to be verified in intra-individual longitudinal studies.

Cortical reorganization of the glutamate synapse in the activity-based anorexia rat model: Impact on cognition

Patients suffering from anorexia nervosa (AN) display altered neural activity, morphological, and functional connectivity in the fronto-striatal circuit. In addition, hypoglutamatergic transmission and aberrant excitability of the medial prefrontal cortex (mPFC) observed in AN patients might underpin cognitive deficits that fuel the vicious cycle of dieting behavior. To provide a molecular mechanism, we employed the activity-based anorexia (ABA) rat model, which combines the two hallmarks of AN (i.e., caloric restriction and intense physical exercise), to evaluate structural remodeling together with alterations in the glutamatergic signaling in the mPFC and their impact on temporal memory, as measured by the temporal order object recognition (TOOR) test. Our data indicate that the combination of caloric restriction and intense physical exercise altered the homeostasis of the glutamate synapse and reduced spine density in the mPFC. These events, paralleled by an impairment in recency discrimination in the TOOR test, are associated with the ABA endophenotype. Of note, after a 7-day recovery period, body weight was recovered and the mPFC structure normalized but ABA rats still exhibited reduced post-synaptic stability of AMPA and NMDA glutamate receptors associated with cognitive dysfunction. Taken together, these data suggest that the combination of reduced food intake and hyperactivity affects the homeostasis of the excitatory synapse in the mPFC contributing to maintain the aberrant behaviors observed in AN patients. Our findings, by identifying novel potential targets of AN, may contribute to more effectively direct the therapeutic interventions to ameliorate, at least, the cognitive effects of this psychopathology.

Cognitive Behavioral and Cognitive Remediation Strategies for Managing Co-Occurring Anorexia Nervosa and Elevated Autism Spectrum Traits

Anorexia nervosa (AN) is a potentially severe eating disorder whose core characteristics include energy intake restriction leading to low body weight. Autism spectrum disorder (ASD) is a developmental disorder characterized by deficits in social interaction and communication as well as repetitive, stereotyped behavior and interests. Both high ASD traits and diagnosed ASD are overrepresented among individuals with AN, and AN and ASD appear to share certain neurocognitive features. These features are associated with the severity of eating disorder symptoms and prolongation of AN. Thus, individuals with AN and high ASD traits or ASD may benefit less from traditional treatment when compared to those with low ASD traits. No previous reviews have summarized what is known about treatment adaptations for individuals with AN and high ASD traits or ASD. The purpose of this narrative review was to investigate the feasibility of cognitive remediation therapy (CRT), cognitive remediation and emotional skill training (CREST), and cognitive behavioral therapy (CBT), and give an overview of treatment modifications for individuals with AN and co-occurring ASD or high ASD traits. We found nine studies that fulfilled our inclusion criteria. The combined results suggest that individuals with AN and high ASD traits or ASD benefit less from CRT, CREST, and CBT than those with AN and low ASD traits. However, CRT and CREST administered in individual format may be associated with improved cognitive flexibility, motivation for change, and decreased alexithymia among adults with AN and high ASD traits or ASD. Individuals with comorbid AN and ASD themselves highlight the importance of treatment adaptations that take the characteristics of ASD into account. In the future, controlled studies of the treatment strategies for individuals with AN and ASD/high ASD traits are needed in order to improve the outcome of individuals with this challenging comorbidity.

Anorexia nervosa and comorbid autism spectrum disorders

PURPOSE OF REVIEW

Traits of autism spectrum disorder (ASD) are overrepresented among individuals with anorexia nervosa (AN) and may also moderate the behavioral manifestation of AN. This review aims to provide an overview of AN and comorbid ASD.

RECENT FINDINGS

Elevated ASD traits do not seem to precede AN among some individuals but are rather related to the illness stage. However, studies have suggested that there are ASD-specific mechanisms for developing AN in a subgroup of individuals with AN. Pronounced traits of ASD and diagnosed ASD are associated with illness prolongation and poorer outcomes in AN, and individuals with AN and elevated ASD traits may benefit less from many of the current treatments. Studies do not support a specific genetic relationship between ASD and AN.

SUMMARY

Recent research encourages the improved recognition of elevated ASD traits in individuals with AN and provides grounds for developing tailored treatments for those with this comorbidity.

[Eating and feeding disorders : New developments]

An overview of eating and feeding disorders according to the future criteria of the International Classification of Diseases (ICD-11) is presented, including information on differential diagnosis, epidemiology, etiology, pathogenesis as well as therapy. Binge-eating disorder is new and the most frequent eating disorder. While anorexia nervosa and bulimia nervosa mostly affect women, the gender ratio in binge-eating disorder is more balanced. Concerning etiology, socio-cultural, biological and psychological factors are discussed. Cognitive behavioral psychotherapy is the best-validated treatment for all three eating disorders. According to the German guidelines for treatment (2019), focal psychodynamic psychotherapy is also a treatment option for anorexia nervosa. Evidence for the positive effect of psychopharmacologic drugs in the treatment of anorexia nervosa is still lacking. Fluoxetine has been shown to have a limited effect in the treatment of bulimia nervosa.

Exploring neuropsychological and socio-emotional task performance in anorexia nervosa: A cluster analytic approach

OBJECTIVE

The aim of this study was to characterise heterogeneity in neuropsychological and socio-emotional task performance in young women with anorexia nervosa (AN) using hierarchical cluster analysis. Further, we aimed to test whether cognitive profiles were associated with differences in clinical variables (body mass index, illness duration and age at diagnosis), psychopathology (eating disorder, autistic symptoms, anxiety and depression) and functional impairment.

METHOD

Set-shifting, central coherence and theory of mind abilities were measured in 118 women with acute or remitted AN. A hierarchical cluster analysis using Ward's method with a Euclidean distance measure was performed with the neuropsychological and socio-emotional variables. Differences between clusters were assessed using ANOVAs.

RESULTS

Four clusters emerged, with significant differences in neuropsychological and socio-emotional task performance. There were no significant differences between clusters in clinical variables, psychopathology or functional impairment, however, these analyses lacked power due to small cluster sizes.

CONCLUSIONS

Our results demonstrate significant heterogeneity in cognitive profiles in AN, supporting a more personalised approach to treatment. Studies in larger samples are required to establish whether these variables map onto clinically significant differences in aetiology, clinical presentation, comorbidity patterns and/or treatment responses.

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.

Cognitive remediation therapy for anorexia nervosa as a rolling group intervention: Data from a longitudinal study in an eating disorders specialized inpatient unit

Objective

Cognitive remediation therapy (CRT) has been proposed as an add‐on treatment approach that could increase the engagement in treatment of anorexia nervosa (AN) patients and reduce maintaining factors, but prior studies have evaluated CRT in individual and group settings, difficult protocols for rehabilitation settings. Our aim is to evaluate the CRT rolling protocol implementation in an inpatient specialised unit.

Methods

A historical longitudinal controlled study was designed to include 31 AN patients for the CRT program, and 28 AN patients treated as usual. The CRT rolling group was implemented in a multidisciplinary inpatient rehabilitation ward with both adolescent and adult patients and an 8‐weeks protocol. To evaluate the treatment implementation effect, different self‐administered questionnaires were used.

Results

The study found greater improvements of the CRT group in clinical symptomatology (p = 0.039), flexibility (p = 0.003), self‐confidence about the ability to change (p < 0.001), and less short‐term focus (p < 0.001), with no differences between restrictive and binge‐purging patients.

Conclusion

This study demonstrates that CRT rolling group protocol is feasible in an inpatient treatment setting and may improve a rehabilitation program's outcome. Our results have shown how CRT can influence cognitive styles considered AN maintenance factors, positively affecting both restrictive and binge‐purge type.

Cognitive remediation therapy (CRT) could be implemented in an inpatient setting with a rolling protocol

CRT improves flexibility, drive to change, and therapy engagement

No differences between restrictive or binge/purge subgroups

Both adolescent and adult patients improved their cognitive styles

The Hunger Games: Homeostatic State-Dependent Fluctuations in Disinhibition Measured with a Novel Gamified Test Battery

Food homeostatic states (hunger and satiety) influence the cognitive systems regulating impulsive responses, but the direction and specific mechanisms involved in this effect remain elusive. We examined how fasting, and satiety, affect cognitive mechanisms underpinning disinhibition using a novel framework and a gamified test-battery. Thirty-four participants completed the test-battery measuring three cognitive facets of disinhibition: attentional control, information gathering and monitoring of feedback, across two experimental sessions: one after overnight fasting and another after a standardised meal. Homeostatic state was assessed using subjective self-reports and biological markers (i.e., blood-derived liver-expressed antimicrobial protein 2 (LEAP-2), insulin and leptin). We found that participants who experienced greater subjective hunger during the satiety session were more impulsive in the information gathering task; results were not confounded by changes in mood or anxiety. Homeostatic state did not significantly influence disinhibition mechanisms linked to attentional control or feedback monitoring. However, we found a significant interaction between homeostatic state and LEAP-2 on attentional control, with higher LEAP-2 associated with faster reaction times in the fasted condition only. Our findings indicate lingering hunger after eating increases impulsive behaviour via reduced information gathering. These findings identify a novel mechanism that may underpin the tendency to overeat and/or engage in broader impulsive behaviours.

The emotional face of anorexia nervosa: The neural correlates of emotional processing

Social-emotional processing difficulties have been reported in Anorexia Nervosa (AN), yet the neural correlates remain unclear. Previous neuroimaging work is sparse and has not used functional connectivity paradigms to more fully explore the neural correlates of emotional difficulties. Fifty-seven acutely unwell AN (AAN) women, 60 weight-recovered AN (WR) women and 69 healthy control (HC) women categorised the gender of a series of emotional faces while undergoing Functional Magnetic Resonance Imaging. The mean age of the AAN group was 19.40 (2.83), WR 18.37 (3.59) and HC 19.37 (3.36). A whole brain and psychophysical interaction connectivity approach was used. Parameter estimates from significant clusters were extracted and correlated with clinical symptoms. Whilst no group level differences in whole brain activation were demonstrated, significant group level functional connectivity differences emerged. WR participants showed increased connectivity between the bilateral occipital face area and the cingulate, precentral gyri, superior, middle, medial and inferior frontal gyri compared to AAN and HC when viewing happy valenced faces. Eating disorder symptoms and parameter estimates were positively correlated. Our findings characterise the neural basis of social-emotional processing in a large sample of individuals with AN.

Cognitive Function in Adults with Enduring Anorexia Nervosa

Anorexia Nervosa (AN) is a severe and often enduring disorder characterized by restriction of food intake, low body weight, fear of weight gain, and distorted body image. Investigations on cognition performance in AN patients have yielded conflicting results. Using an established and sensitive computerized cognitive test battery, we aimed to assess core aspects of cognitive function, including attention span, information processing, reasoning, working and episodic memory, in AN patients and controls. Patients were recruited from the Danish Prospective Longitudinal all-comer inclusion study in Eating Disorders (PROLED). Included were 26 individuals with AN and 36 healthy volunteers (HV). All were tested with CogTrack (an online cognitive assessment system) at baseline, and AN patients were tested again at a follow-up time point after weight increase (n = 13). At baseline, AN patients showed faster reaction times in the attention tasks, as well as increased accuracy in grammatical reasoning compared to HV. There were no differences in cognitive function between AN patients and HV in the other cognitive domains measured (sustained attention, working and episodic memory, speed of retrieval, and speed of grammatical reasoning). No differences were visible in the AN sample between baseline and follow-up. Performance did not correlate with any clinical variables in the AN sample. These findings supplement results from other studies suggesting increased concentration and reasoning accuracy in patients suffering from AN, who showed increased performance in cognitive tasks despite their illness.

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.

Iowa Gambling Task and Distortion in Perception of Body Image Among Adolescent Women With Eating Disorders

The Iowa gambling task (IGT) is an instrument for the neuropsychological evaluation of cognitive and emotional decision making (DM) processes that was created to test the somatic marker hypothesis (SMH) described by Damasio in 1994. It was initially applied to patients with frontal lobe lesions due to its association with executive functions but was subsequently used on patients with a variety of disorders. Although the DM process is inherently perceptual, few studies have applied the IGT to examine DM processes in patients with eating disorders (EDs), and even fewer have associated the IGT to the perceptual distortion of body image (PDBI) in this population. People diagnosed with ED exhibit heightened control over their somatic responses-for example, they can delay digestion for hours-and DM may be affected in this condition. This study compares the performance of two samples of adolescent women-hospitalized patients with ED, and healthy controls with similar demographic characteristics-on the IGT using body image as a possible factor in the SMH. Seventy-four women with a mean age of 14.97 years (SD = 2.347) participated. To analyze their body self-image, we used the figure-rating scale and compared the results with their body mass index (BMI). Correlations between indices of the IGT and distortion in body image were then explored. The results revealed significant differences between the groups in terms of evolving performance on the partial IGT. Patients with ED performed worse than their healthy counterparts in the last 40 trials and exhibited greater distortions in their body image, especially in terms of overestimation. Indices of these distortions were negatively correlated with the total IGT. These results are compatible with the SMH because they suggest that patients with ED evinced blindness with regard to the future, as described by their authors. In addition, a negative correlation was found between the IGT and PDBI, showing that a more distorted body image was associated with lower IGT, that is, more disadvantageous or riskier decisions were made by the subjects with more distortion.

Strengthened Default Mode Network Activation During Delay Discounting in Adolescents with Anorexia Nervosa After Partial Weight Restoration: A Longitudinal fMRI Study

The capacity of patients with anorexia nervosa (AN) to resist food-based rewards is often assumed to reflect excessive self-control. Previous cross-sectional functional magnetic resonance imaging (fMRI) studies utilizing the delay discounting (DD) paradigm, an index of impulsivity and self-control, suggested altered neural efficiency of decision-making in acutely underweight patients (acAN) and a relative normalization in long-term, weight-recovered individuals with a history of AN (recAN). The current longitudinal study tested for changes in functional magnetic resonance imaging (fMRI) activation during DD associated with intensive weight restoration treatment. A predominately adolescent cohort of 22 female acAN patients (mean age—15.5 years) performed an established DD paradigm during fMRI at the beginning of hospitalization and again after partial weight restoration (≥12% body mass index (BMI) increase). Analyses investigated longitudinal changes in both reward valuation and executive decision-making processes. Additional exploratory analyses included comparisons with data acquired in aged-matched healthy controls (HC) as well as probes of functional connectivity between empirically identified nodes of the “task-positive” frontoparietal control network (FPN) and “task-negative” default-mode network (DMN). While treatment was not associated with changes in behavioral DD parameters or activation, specific to reward processing, deactivation of the DMN during decision-making was significantly less pronounced following partial weight restoration. Strengthened DMN activation during DD might reflect a relative relaxation of cognitive overcontrol or improved self-referential, decision-making. Together, our findings present further evidence that aberrant decision-making in AN might be remediable by treatment and, therefore, might constitute an acute effect rather than a core trait variable of the disorder.

Neuroscience of Adolescent Anorexia Nervosa: Implications for Family-Based Treatment (FBT)

Over the past 20 years significant progress has been made to elucidate some of the neurobiological underpinnings of the development and maintenance of anorexia nervosa and their possible implications for treatment. There is increasing evidence supporting the notion that anorexia nervosa shares neurobehavioral patterns with anxiety disorders and involves reward processing aberrations and habit formation. There is consensus for the need of early intervention to ameliorate the effects of starvation on the adolescent brain and the effects of illness duration on neurodevelopment. Family-based treatment (FBT) is the first line evidence-based treatment for adolescents with anorexia nervosa achieving sustainable full remission rates of over 40%. FBT has an agnostic treatment approach and its mechanisms of change have until now not been fully understood. To help fill this gap in theoretical understanding, this paper will provide a review of the treatment model of FBT through a neuroscientific lens. It argues that FBT is well designed to address the implications of current key findings of the neuroscience of anorexia nervosa and that it is also well aligned with the current understanding of neuroscience principles underpinning therapeutic change. The paper supports the perspective that FBT utilizes principles of parent facilitated exposure response prevention. It concludes that an integration of a neuroscience perspective to the provision of FBT will assist the clinician in their practice of FBT.