Central coherence in women with bulimia nervosa

Group cognitive remediation therapy for adolescents with anorexia nervosa: Outcomes before, after, and during follow-up in a real-world setting in Japan

Objective: Cognitive remediation therapy (CRT) can be used as an adjunct treatment for adolescents with severe and complex anorexia nervosa (AN) requiring inpatient treatment. However, there has been only one study on CRT for adolescents with AN in Japan. This study explored group CRT as an adjunct to inpatient treatment for Japanese adolescents with severe and complex AN requiring inpatient care. Methods: Thirty-one adolescents with AN underwent group CRT. Neuropsychological (set-shifting and central coherence) and psychological assessments (motivation, self-esteem, and depressive symptoms) were measured before and after the intervention. Weight and AN symptoms were measured before and after the intervention and at follow-up, and the adolescents completed post-intervention and follow-up questionnaires. Results: Set-shifting led to medium to large effect size improvements. Medium effect size improvements in central coherence and depressive symptoms were also observed. The feedback from the adolescents was mainly positive, and the treatment completion rate was high. The patients also reported that the skills learned through group CRT could be applied in daily life. Conclusion: Group CRT may be beneficial for adolescents with severe and complex AN who require inpatient care.

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

Introduction

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

Method and Results

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

Discussion

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

Mediating Mechanisms of Perfectionism: Clinical Comorbidity of OCD and ED

Obsessive-compulsive disorder (OCD) and eating disorders (ED) share common causal factors and often represent similar entities. Studies on obsessive-compulsive disorders and eating disorders reveal a significant correlation between maladaptive perfectionism. The objective of this study is to evaluate the predictive variables of perfectionism in patients diagnosed with Anorexia Nervosa (AN), Bulimia Nervosa (BN) and OCD using a structural equation model (SEM). The sample consisted of 187 participants (60.9% women, 39.1% men) with a mean age of 26.68 (SD = 10.97). The findings reveal that the model is the same in all the disorders evaluated, achieving an adequate fit: χ2 = 7.95 (p = 0.000), RMSEA = 0.087 (95% confidence interval: 0.00 to 0.02), CFI = 0.991, TLI = 0.951 and with an overall predictive capacity of around 30% (CD = 0.318). It is recommended that future studies address the subtypes of disorders evaluated using longitudinal designs.

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.

Impulsivity and compulsivity in anorexia and bulimia nervosa: A systematic review

This study aimed to systematically appraise cross-sectional research that compared the cognitive performance of individuals in the acute phase of BN and/or AN to HCs on measures of impulsivity and compulsivity. The results of the systematic review showed support for the trans-diagnostic approach to eating disorders. There was no strong evidence to support the characterisation of AN as high in compulsivity (and low in impulsivity), nor to support the characterisation of BN as high in impulsivity (and low in compulsivity). There appeared to be mixed findings for both impulsivity and compulsivity across AN and BN. Results were highly variable due to the heterogeneous tasks used, and lack of replication across studies. There was no consensus amongst the included studies on the most appropriate task and/or outcome measures that should be used to study the constructs of impulsivity and compulsivity.

Contribution of executive functions to eating behaviours in obesity and eating disorders

BACKGROUND

Patients with eating disorders (ED) or obesity show difficulties in tasks assessing decision-making, set-shifting abilities and central coherence.

AIMS

The aim of this study was to explore executive functions in eating and weight-related problems, ranging from restricting types of ED to obesity.

METHOD

Two hundred and eighty-eight female participants (75 with obesity; 149 with ED: 76 with restrictive eating, 73 with bingeing-purging symptoms; and 64 healthy controls) were administered the Wisconsin Card Sorting Test, the Iowa Gambling Task, and the Group Embedded Figures Test to assess set-shifting, decision-making and central coherence, respectively.

RESULTS

Participants with either obesity or ED performed poorly on tests measuring executive functioning compared with healthy controls, even after controlling for age and intelligence. Both participants with obesity and participants with ED showed a preference for global information processing.

CONCLUSIONS

The findings suggest that treatments for obesity and ED would benefit from addressing difficulties in cognitive functioning, in addition to the more evident clinical symptoms related to eating, body weight and shape.

Visual-Constructional Ability in Individuals with Severe Obesity: Rey Complex Figure Test Accuracy and the Q-Score

The aims of this study were to investigate visual-construction and organizational strategy among individuals with severe obesity, as measured by the Rey Complex Figure Test (RCFT), and to examine the validity of the Q-score as a measure for the quality of performance on the RCFT. Ninety-six non-demented morbidly obese (MO) patients and 100 healthy controls (HC) completed the RCFT. Their performance was calculated by applying the standard scoring criteria. The quality of the copying process was evaluated per the directions of the Q-score scoring system. Results revealed that the MO did not perform significantly lower than the HC on Copy accuracy (mean difference −0.302, CI −1.374 to 0.769, p = 0.579). In contrast, the groups did statistically differ from each other, with MO performing poorer than the HC on the Q-score (mean −1.784, CI −3.237 to −0.331, p = 0.016) and the Unit points (mean −1.409, CI −2.291 to −0.528, p = 0.002), but not on the Order points score (mean −0.351, CI −0.994 to 0.293, p = 0.284). Differences on the Unit score and the Q-score were slightly reduced when adjusting for gender, age, and education. This study presents evidence supporting the presence of inefficiency in visuospatial constructional ability among MO patients. We believe we have found an indication that the Q-score captures a wider range of cognitive processes that are not described by traditional scoring methods. Rather than considering accuracy and placement of the different elements only, the Q-score focuses more on how the subject has approached the task.

Group cognitive remediation therapy for younger adolescents with anorexia nervosa: a feasibility study in a Japanese sample

OBJECTIVE

Cognitive remediation therapy (CRT) aims to increase patients' cognitive flexibility by practicing new ways of thinking as well as facilitating bigger picture thinking, supporting patients with relevant tasks and encouraging an awareness of their own thinking styles. CRT has been applied in the treatment of adult anorexia nervosa (AN), and has been shown to be effective and acceptable. In adolescents, CRT has been piloted on both individual and group format. However, no studies are published in CRT for adolescents with AN in a Japanese sample. The objectives of this study were to assess the feasibility, to estimate effect sizes for the purpose of designing a larger study, and to assess the acceptability of a CRT group for younger adolescents with AN in a Japanese sample.

METHODS

Group CRT interventions were carried out with a total of seven adolescents with AN. Neuropsychological and psychological assessments (motivation, self-efficacy and depression) were administered before and after the group intervention. The participants completed worksheets (documents of participants' thinking about their thinking style and the relation of the skills that they learnt through each session to real-life) and questionnaires after the group.

RESULTS

There were small effect sizes differences between the part of the pre and post neuropsychological tests and the pre and post ability to change (motivation). There were medium effect sizes differences between the pre and post depressive symptoms and importance to change (motivation). There was a large effect size shown between the pre and post weights. All participants were able to reflect on their own thinking styles, such as having difficulty with changing feelings and the tendency to focus on details in real-life. Adolescents' feedback was positive, and the rate of dropout was low.

CONCLUSION

CRT groups could be feasible and acceptable for younger adolescents with AN in a Japanese sample. Trial registration UMIN No. 000020623. Registered 18 January 2016.

Central Coherence in Eating Disorders: A Synthesis of Studies Using the Rey Osterrieth Complex Figure Test

Background

Large variability in tests and differences in scoring systems used to study central coherence in eating disorders may lead to different interpretations, inconsistent findings and between study discrepancies. This study aimed to address inconsistencies by collating data from several studies from the same research group that used the Rey Osterrieth Complex Figure Test (Rey Figure) in order to produce norms to provide benchmark data for future studies.

Method

Data was collated from 984 participants in total. Anorexia Nervosa, Bulimia Nervosa, recovered Anorexia Nervosa, unaffected family members and healthy controls were compared using the Rey Figure.

Results

Poor global processing was observed across all current eating disorder sub-groups and in unaffected relatives. There was no difference in performance between recovered AN and HC groups.

Conclusions

This is the largest dataset reported in the literature and supports previous studies implicating poor global processing across eating disorders using the Rey Figure. It provides robust normative data useful for future studies.

Reward-Based Spatial Learning in Teens With Bulimia Nervosa

OBJECTIVE

To assess the functioning of mesolimbic and fronto-striatal areas involved in reward-based spatial learning in teenaged girls with bulimia nervosa (BN) that might be involved in the development and maintenance of maladaptive behaviors characteristic of the disorder.

METHOD

We compared functional magnetic resonance imaging blood oxygen level-dependent response in 27 adolescent girls with BN to that of 27 healthy, age-matched control participants during a reward-based learning task that required learning to use extra-maze cues to navigate a virtual 8-arm radial maze to find hidden rewards. We compared groups in their patterns of brain activation associated with reward-based spatial learning versus a control condition in which rewards were unexpected because they were allotted pseudo-randomly to experimentally prevent learning.

RESULTS

Both groups learned to navigate the maze to find hidden rewards, but group differences in brain activity associated with maze navigation and reward processing were detected in the fronto-striatal regions and right anterior hippocampus. Unlike healthy adolescents, those with BN did not engage the right inferior frontal gyrus during maze navigation, activated the right anterior hippocampus during the receipt of unexpected rewards (control condition), and deactivated the left superior frontal gyrus and right anterior hippocampus during expected reward receipt (learning condition). These patterns of hippocampal activation in the control condition were significantly associated with the frequency of binge-eating episodes.

CONCLUSION

Adolescents with BN displayed abnormal functioning of the anterior hippocampus and fronto-striatal regions during reward-based spatial learning. These findings suggest that an imbalance in control and reward circuits may arise early in the course of BN. Clinical trial registration information-An fMRI Study of Self-Regulation in Adolescents With Bulimia Nervosa; https://clinicaltrials.gov/; NCT00345943.

Central Coherence, Visuoconstruction and Visual Memory in Patients with Eating Disorders as Measured by Different Scoring Methods of the Rey Complex Figure Test

OBJECTIVE

The aims of this study were to examine the performance of eating disorder (ED) patients on the Rey Complex Figure Test and to investigate the validity of the Q-score as a new method for measuring central coherence (CC).

METHOD

Forty-one patients with anorexia nervosa, 40 patients with bulimia nervosa and 40 healthy controls completed the Rey Complex Figure Test, which was scored both quantitatively and qualitatively.

RESULTS

Both ED groups scored lower than the healthy controls on copy, recall and the Q-score. For the anorexia nervosa group, performance on the Central Coherence Index was associated with the nadir body mass index. Performance on the recall measures was independently associated with the nadir body mass index and depressive symptoms for the bulimia nervosa group. There was a strong correlation between the Q-score and the Central Coherence Index (r = 0.77).

DISCUSSION

The study reveals different levels of CC and suggests that the Q-score might be an applicable method for measuring CC in ED patients.

Central coherence in adolescents with bulimia nervosa spectrum eating disorders

BACKGROUND

Weak central coherence-a tendency to process details at the expense of the gestalt-has been observed among adults with bulimia nervosa (BN) and is a potential candidate endophenotype for eating disorders (EDs). However, as BN behaviors typically onset during adolescence it is important to assess central coherence in this younger age group to determine whether the findings in adults are likely a result of BN or present earlier in the evolution of the disorder. This study examines whether the detail-oriented and fragmented cognitive inefficiency observed among adults with BN is observable among adolescents with shorter illness duration, relative to healthy controls.

METHOD

The Rey-Osterrieth Complex Figure Test (RCFT) was administered to a total of 47 adolescents with DSM5 BN, 42 with purging disorder (PD), and 25 healthy controls (HC). Performance on this measure was compared across the three groups.

RESULTS

Those with BN and PD demonstrated significantly worse accuracy scores compared to controls in the copy and delayed recall condition with a moderate effect size. These findings were exacerbated when symptoms of BN increased.

DISCUSSION

Poorer accuracy scores reflect a fragmented and piecemeal strategy that interferes with visual-spatial integration in BN spectrum disorders. This cognitive inefficiency likely contributes to broad difficulties in executive functioning in this population especially in the context of worsening bulimic symptoms. The findings of this study support the hypothesis that poor global integration may constitute a cognitive endophenotype for BN.

Neuropsychological function in patients with anorexia nervosa or bulimia nervosa

OBJECTIVE

This study explored the neuropsychological performance of patients diagnosed with anorexia nervosa (AN) or bulimia nervosa (BN) compared with healthy controls (HCs). An additional aim was to investigate the effect of several possible mediators on the association between eating disorders (EDs) and cognitive function.

METHOD

Forty patients with AN, 39 patients with BN, and 40 HCs who were comparable in age and education were consecutively recruited to complete a standardized neuropsychological test battery covering the following cognitive domains: verbal learning and memory, visual learning and memory, speed of information processing, visuospatial ability, working memory, executive function, verbal fluency, attention/vigilance, and motor function.

RESULTS

The AN group scored significantly below the HCs on eight of the nine measured cognitive domains. The BN group also showed inferior performance on six cognitive domains. After adjusting for possible mediators, the nadir body mass index (lowest lifetime BMI) and depressive symptoms explained all findings in the BN group. Although this adjustment reduced the difference between the AN and HC groups, the AN group still performed worse than the HCs regarding verbal learning and memory, visual learning and memory, visuospatial ability, working memory, and executive functioning.

DISCUSSION

Patients with EDs scored below the HCs on several cognitive function measures, this difference being most pronounced for the AN group. The nadir BMI and depressive symptoms had strong mediating effects. Longitudinal studies are needed to identify the importance of weight restoration and treatment of depressive symptoms in the prevention of a possible cognitive decline.

An Update on Evidence-Based Psychosocial Treatments for Eating Disorders in Children and Adolescents

Eating disorders are relatively common and serious disorders in adolescents. However, there are few controlled psychosocial intervention studies with this younger population. This review updates a previous Journal of Clinical Child and Adolescent Psychology review published in 2008. The recommendations in this review were developed after searching the literature including PubMed/Medline and employing the relevant medical subject headings. In addition, the bibliographies of book chapters and treatment guideline articles were reviewed; last, colleagues were asked for suggested additional source materials. Psychosocial treatments examined include family therapy, individual therapy, cognitive behavioral therapy, interpersonal psychotherapy, cognitive training, and dialectical behavior therapy. Using the most recent Journal of Clinical Child and Adolescent Psychology methodological review criteria, family treatment-behavior (FT-B) is the only well-established treatment for adolescents with anorexia nervosa. Family treatment-systemic and insight oriented individual psychotherapy are probably efficacious treatments for adolescents with anorexia nervosa. There are no well-established treatments for adolescents with bulimia nervosa, binge eating disorder, or avoidant restrictive food intake disorder. Possibly efficacious psychosocial treatments for adolescent bulimia nervosa include FT-B and supportive individual therapy. Internet-delivered cognitive behavioral therapy is a possibly efficacious treatment for binge eating disorder. Experimental treatments for adolescent eating disorders include enhanced cognitive behavioral therapy, dialectical behavioral therapy, cognitive training, and interpersonal psychotherapy. FT-B is the only well-established treatment for adolescent eating disorders. Additional research examining treatment for eating disorders in youth is warranted.

Cognitive profile of children and adolescents with anorexia nervosa

Objective

Few studies of cognitive functioning in children and adolescents with anorexia nervosa (AN) have been conducted. The aim of this study was to examine the neurocognitive and intelligence profile of this clinical group.

Method

The study was a matched case–control (N = 188), multi-centre study including children and adolescents with AN (N = 94) and healthy control participants (N = 94).

Results

The results suggest that Full Scale Intelligence Quotient (Wechsler Intelligence Scale for Children-III/Wechsler Adult Intelligence Scale-III) in this patient group is close to the normal population mean of 100. Individuals with AN exhibited significantly worse performance in nonverbal intelligence functions (i.e. Wechsler Intelligence Scale for Children-III/Wechsler Adult Intelligence Scale-III, Perceptual Organization Index) and in verbal memory (Test of Memory and Learning—Second Edition, Memory for Stories) and motor speed (Cambridge Neuropsychological Test Automated Battery, Simple and Choice Reaction Time) compared with healthy control participants. No significant difference in set-shifting ability (Cambridge Neuropsychological Test Automated Battery, Intra-Extra Dimensional Set Shift and Trail Making Test B) was found.

Conclusions

Inefficiency in nonverbal intelligence functions and in specific cognitive functions was found in this study of children and adolescents with AN. © 2014 The Authors. European Eating Disorders Review published by John Wiley & Sons, Ltd.

Reliability and validity of the Leuven Perceptual Organization Screening Test (L-POST)

Neuropsychological tests of visual perception mostly assess high-level processes like object recognition. Object recognition, however, relies on distinct mid-level processes of perceptual organization that are only implicitly tested in classical tests. Furthermore, the psychometric properties of the existing instruments are limited. To fill this gap, the Leuven perceptual organization screening test (L-POST) was developed, in which a wide range of mid-level phenomena are measured in 15 subtests. In this study, we evaluated reliability and validity of the L-POST. Performance on the test is evaluated relative to a norm sample of more than 1,500 healthy control participants. Cronbach's alpha of the norm sample and test-retest correlations for 20 patients provide evidence for adequate reliability of L-POST performance. The convergent and discriminant validity of the test was assessed in 40 brain-damaged patients, whose performance on the L-POST was compared with standard clinical tests of visual perception and other measures of cognitive function. The L-POST showed high sensitivity to visual dysfunction and decreased performance was specific to visual problems. In conclusion, the L-POST is a reliable and valid screening test for perceptual organization. It offers a useful online tool for researchers and clinicians to get a broader overview of the mid-level processes that are preserved or disrupted in a given patient.

Executive functioning in overweight individuals with and without loss-of-control eating

OBJECTIVE

The current study sought to examine executive function (EF) in overweight individuals with and without loss-of-control (LOC) eating.

METHOD

Eighty overweight and obese individuals entering a behavioural weight loss trial with (n=18) and without (n=62) LOC eating were administered a clinical interview and neuropsychological battery designed to assess self-regulatory control, planning, delayed discounting and working memory.

RESULTS

After controlling for age, IQ and depression, individuals with LOC eating performed worse on tasks of planning and self-regulatory control and did not differ in performance on other tasks.

DISCUSSION

Results indicate that overweight individuals with LOC eating display relative deficits in EF compared with overweight individuals without LOC eating. Planning and self-regulatory control deficits in particular may contribute to dysregulated eating patterns, increasing susceptibility to LOC episodes. Future research should examine how EF deficits relate to treatment outcome.

Neurocognitive functioning in adolescents with eating disorders: a population-based study

INTRODUCTION

Neurocognitive deficits have been identified in eating disorders, including anorexia nervosa and bulimia nervosa. However, current data do not allow for firm conclusions regarding the nature or extent of these deficits. The current study aimed to evaluate neurocognitive functioning in a population-based sample of adolescents with and without eating disorders.

METHODS

Participants (N=669) were drawn from the Western Australian Pregnancy Cohort (Raine) Study. Cognitive testing was conducted using the computerised CogState assessment battery. Eating disorder symptoms were assessed using questions adapted from the Child Eating Disorder Examination and Eating Disorder Examination-Questionnaire. Adolescents who met full or partial criteria for a DSM-IV eating disorder (n=58) were compared to adolescents with no significant eating pathology (n=592).

RESULTS

The eating disorder sample showed impaired performance on measures of executive functioning, including global processing and set shifting, but performed better than control participants on measures of visual attention and vigilance.

CONCLUSIONS

This is the first study to evaluate neurocognitive functioning in a population-based sample of adolescents with eating disorders. Support is provided for weak central coherence and set-shifting difficulties early in the course of eating disorders. Research is needed to determine if these deficits precede and predict eating disorder onset.

Cognitive flexibility, central coherence and social emotional processing in males with an eating disorder

OBJECTIVES

Females are more likely to develop an eating disorder (ED) than males. Studies of affected men may therefore inform models of risk and resilience to EDs. The aim of this study was to examine putative neurocognitive intermediate phenotypes of EDs in affected males.

METHODS

Cognitive flexibility, central coherence (global/detail processing), complex emotion recognition and social-threat sensitivity were investigated in men with EDs and healthy men. Measures of distress, perfectionism, and obsessive compulsivity were collected.

RESULTS

Men with EDs were more cognitively inflexible across tasks and had more difficulty integrating global information than healthy men. Unexpectedly, there were no group differences on a visuospatial task of detail processing or on social-emotional processing tasks. Men with EDs had higher scores on measures of distress, perfectionism and obsessive compulsivity than healthy men.

CONCLUSIONS

Men with EDs share some of the intermediate cognitive phenotype present in women with EDs. Like their female counterparts, males with EDs show an inflexible, fragmented cognitive style. However, relative to healthy men, men with EDs do not have superior detail processing abilities, poor emotion recognition or increased sensitivity to social-threat. It is possible that gender differences in social-threat processing contribute to the female preponderance of EDs.

Assessing the relationship between eating disorder psychopathology and autistic traits in a non-clinical adult population

PURPOSE

Previous research demonstrates a genetic and behavioural link between eating disorders and autism spectrum disorders, and a recent study (Coombs et al. in Br J Clin Psychol 50:326-338, 2011) extends this link to typical populations, showing a positive correlation between behaviours in typically developing children. The purpose of the present study was to examine whether this relationship continues beyond development, by studying the link between behaviours in a non-clinical adult population.

METHODS

We examined associations between performance on measures relating to autistic traits and disordered eating. Undergraduate students, equally balanced by gender and by subject studied (i.e. humanity or science), completed three tasks: to measure autistic traits, participants were administered the Embedded Figures Test (EFT) and the Autism-Spectrum Quotient (AQ). Eating disorder symptomatology was measured by the Eating Attitudes Test (Eat-26).

RESULTS

Our data revealed a significant positive correlation between scores on the AQ and Eat-26. Multiple linear regressions showed that higher scores on the AQ were particularly associated with higher scores on the Bulimia & Food Preoccupation subscale of the Eat-26. EFT performance was positively related to behaviours associated with autism and eating disorders, although not reliably so.

CONCLUSIONS

These data support the broader link between autistic traits and disordered eating in the non-clinical population, and demonstrate that it extends into adulthood (a time at which autistic behaviours can decrease). This work carries implications for the development of cognitive therapies for people with eating disorders.

Theory of mind and central coherence in eating disorders: two sides of the same coin?

The aim of this study was to evaluate central coherence and theory of mind (ToM) and explore the relationships between these domains in patients with eating disorders (ED). ToM and central coherence were assessed in 72 women [24 with anorexia nervosa (AN), 24 with bulimia nervosa (BN) and 24 healthy controls (HC)]. The Reading the Mind in the Eyes (RME) and the Faux Pas Test (FPT) to measure ToM, and the copy strategy of the Rey-Osterrieth Complex Figure Test to assess central coherence were used. It was observed that patients with ED had a decrease in central coherence skills compared with the control group; that patients with anorexia had a poor performance on RME ToM task compared with BN patients and HCs, and also that these measures were related in both clinical groups. The statistically significant correlation between them suggests that the central coherence and ToM measures might involve common cognitive processes. These results provide a better understanding of the nature of the socio-cognitive deficits observed in patients with eating disorders.

Neuropsychological variables and clinical status in anorexia nervosa: relationship between visuospatial memory and central coherence and eating disorder symptom severity

AIM

To explore the relationship between visuospatial memory, weak central coherence, and eating disorder (ED) symptoms in anorexia nervosa (AN) inpatients.

SAMPLE

31 female AN inpatients.

METHODS

Rey complex figure test (RCFT) was used to assess both visuospatial memory and central coherence. RCFT consisted of copy and recall trials. ED symptoms were assessed by The Eating Disorder Examination-Questionnaire (EDE-Q) and The Clinical and Research Inventory for Eating Disorders (CR-EAT).

RESULTS

We found a statistically significant negative correlation between recall accuracy and the total EDE-Q score. Furthermore, recall accuracy and recall central coherence significantly negatively correlate with several EDE-Q and CR-EAT scales.

CONCLUSIONS

These findings may contribute to a better understanding of cognitive impairments specifically in ED, and to refining interventions aiming at their improvement.

A review of cognitive neuropsychiatry in the taxonomy of eating disorders: state, trait, or genetic?

A greater understanding of neuropsychological traits in eating disorders may help to construct a more biologically based taxonomy. The aim of this paper is to review the current evidence base of neuropsychological traits in people with eating disorders. Evidence of difficulties in set shifting, weak central coherence, emotional processing difficulties, and altered reward sensitivity is presented for people both in the acute and recovered phase of the illness. These traits are also seen in first degree relatives. At present there is limited research linking these neuropsychological traits with genetic and neuroanatomical measures. In addition to improving the taxonomy of eating disorders, neuropsychological traits may be of value in producing targeted treatments.

Set shifting and central coherence as neurocognitive endophenotypes in eating disorders: a preliminary investigation in twins

OBJECTIVES

Weak central coherence and poor set shifting are risk markers for eating disorders that are present post recovery and in first degree relatives. The aim of this study was to examine these traits in twins with eating disorders.

METHODS

Neuropsychological tests were administered to 114 female twins (n = 53 met lifetime DSM-IV eating disorder criteria, n = 19 non-eating disorder cotwins and n = 42 controls). Within pair correlations for monozygotic (MZ) and dizygotic (DZ) twins were calculated and generalised estimating equations (GEE) compared probands, with non-eating disorder cotwins and controls.

RESULTS

The genetic basis was highest for the central coherence tasks (Rey-Osterrieth Complex Figure Task: MZ twins r = 0.44 [CI: 0.07-0.70, P = 0.01] and Group Embedded Figures Test: MZ twins r = 0.58 [CI: 0.26-0.79, P = 0.00]). Poor set shifting was related to obsessive compulsive symptoms in both individuals with eating disorders and their non-eating disorder cotwins (r = 0.2-0.5).

CONCLUSION

Set shifting abilities and central coherence appear to be endophenotypes associated with eating disorders.

Is attention to detail a similarly strong candidate endophenotype for anorexia nervosa and bulimia nervosa?

OBJECTIVES

To investigate whether attention to detail is a similarly strong candidate endophenotype of anorexia (AN) and bulimia nervosa (BN), and to explore the incidence and clinical correlates of attention to detail.

METHODS

A total of 266 women (including AN, BN, recovered AN, unaffected sisters of AN/BN & control women) undertook a thorough clinical assessment and were administered two neuropsychological measures of attention to detail (Group Embedded Figure Test; Rey-Osterrieth Complex Figure).

RESULTS

Superior attention to detail was found across all AN groups including recovered AN and unaffected AN sisters. Those with BN and their unaffected sisters showed a profile more consistent with poor global integration. The combined effect of superior attention to detail and poor global integration ("weak coherence") was present in 42.3% of active cases and corresponded with a more severe illness, elevated obsessive-compulsive symptoms, and a higher likelihood of comorbid clinical anxiety and self-harm.

CONCLUSIONS

Attention to detail is a stronger candidate endophenotype of AN compared to BN, where poor global integration may be more relevant. The unique contribution of both aspects of weak coherence (superior attention to detail/poor global integration) requires further exploration and understanding in both eating disorders. Integrating cognitive remediation of these traits into treatment for the subset of patients it is relevant for may improve outcome.

Do girls with anorexia nervosa have elevated autistic traits?

BACKGROUND

Patients with anorexia may have elevated autistic traits. In this study, we tested test whether patients with anorexia nervosa (anorexia) have an elevated score on a dimensional measure of autistic traits, the Autism Spectrum Quotient (AQ), as well as on trait measures relevant to the autism spectrum: the Empathy Quotient (EQ), and the Systemizing Quotient (SQ).

METHODS

Two groups were tested: (1) female adolescents with anorexia: n = 66, aged 12 to 18 years; and (2) female adolescents without anorexia: n =1,609, aged 12 to 18 years. Both groups were tested using the AQ, EQ, and SQ, via the parent-report adolescent versions for patients aged 12 to 15 years old, and the self-report adult versions for patients aged over 16 years.

RESULTS

As predicted, the patients with anorexia had a higher AQ and SQ. Their EQ score was reduced, but only for the parent-report version in the younger age group. Using EQ-SQ scores to calculate 'cognitive types', patients with anorexia were more likely to show the Type S profile (systemizing (S) better than empathy (E)), compared with typical females.

CONCLUSIONS

Females with anorexia have elevated autistic traits. Clinicians should consider if a focus on autistic traits might be helpful in the assessment and treatment of anorexia. Future research needs to establish if these results reflect traits or states associated with anorexia.

Do restrictive and bingeing/purging subtypes of anorexia nervosa differ on central coherence and set shifting?

OBJECTIVE

Anorexia nervosa (AN) has been associated with weak central coherence (CC) and weak set shifting (SS). The main aim of this study was to examine possible differences between restrictive AN (AN-R) and bingeing/purging AN (AN-BP) on these features.

METHODS

A total of 31 patients with AN-R, 20 patients with AN-BP and 26 healthy controls (HC) completed five neuropsychological tests (Block Design, Object Assembly, an adapted task-switching paradigm, Wisconsin Card Sorting Test and Trail Making Test).

RESULTS

Using Block Design and Object Assembly, indicative for CC, AN-R patients performed significantly worse than AN-BP patients and HC, without any difference between AN-BP and HC. On SS measures, no group differences were observed.

DISCUSSION

The results suggest that cognitive profiles of AN-R and AN-BP patients differ significantly on CC and not on SS. Our current findings support the idea that the two subtypes of AN have a distinctive underlying nature and might need a different approach in cognitive remediation.

Neuropsychology of eating disorders: 1995-2012

Eating disorders are considered psychiatric pathologies that are characterized by pathological worry related to body shape and weight. The lack of progress in treatment development, at least in part, reflects the fact that little is known about the pathophysiologic mechanisms that account for the development and persistence of eating disorders. The possibility that patients with eating disorders have a dysfunction of the central nervous system has been previously explored; several studies assessing the relationship between cognitive processing and certain eating behaviors have been conducted. These studies aim to achieve a better understanding of the pathophysiology of such diseases. The aim of this study was to review the current state of neuropsychological studies focused on eating disorders. This was done by means of a search process covering three relevant electronic databases, as well as an additional search on references included in the analyzed papers; we also mention other published reviews obtained by handsearching.

Measuring state trait properties of detail processing and global integration ability in eating disorders

OBJECTIVES

Women with eating disorders (EDs) are reported to have strengths in local or detailed information processing and difficulties with coherence or global processing/integration.

METHODS

This study aimed to replicate these findings and additionally explore a global integration task which has not previously been reported for an ED group, the Fragmented Pictures Task (FPT). Two hundred and twenty-two women (50 with anorexia nervosa (AN), 48 with bulimia nervosa (BN), 35 recovered from AN and 89 controls (HC)) completed the Rey-Osterrieth Complex Figure Task (RCFT) to measure global/local processing strategies, the Group Embedded Figures Task (GEFT) to measure local processing and the FPT to measure global integration.

RESULTS

Superior detail processing skills (GEFT) and a tendency to utilise detail processing strategies (RCFT) were associated with having AN, BN and being in recovery from AN. Global integration difficulties (FPT) were only observed in acute AN, whereas participants in the BN and recovered group performed similarly to HCs.

CONCLUSIONS

People currently ill with, and recovered from EDs are skilled at detail processing. The acute phase of AN is associated with difficulties in global integration.

Development and validation of the Detail and Flexibility Questionnaire (DFlex) in eating disorders

Whilst neuropsychological testing provides the most accurate profile of cognitive functioning, the time consuming nature of individual assessment deems it impossible for many research and clinical settings. This paper presents the development and validation of the Detail and Flexibility Questionnaire (DFlex), a 24-item self-report scale measuring two aspects of neurocognitive functioning; cognitive rigidity (difficulty with set-shifting/flexibility) and attention to detail (weak coherence). Exploratory factor analysis extracted two subscales, further confirmed and refined by item response analysis. Both subscales showed high internal reliability, construct validity (as compared to relevant subscales of the Autistic-Spectrum Quotient) and strong discriminant validity with large effect sizes found between both lifetime eating disorder and healthy control groups, and between current and recovered anorexia nervosa. We suggest using the cognitive rigidity and attention to detail subscales independently to give a rough approximation of these two aspects of cognitive style as they manifest in the context of everyday life.

Neurocognition in bulimic eating disorders: a systematic review

Van den Eynde F, Guillaume S, Broadbent H, Stahl D, Campbell IC, Schmidt U, Tchanturia K. Neurocognition in bulimic eating disorders: a systematic review.

OBJECTIVE

  The aim of this study was to review the literature on neurocognition comparing people with a bulimic eating disorder in the acute phase of the illness with healthy controls (HC).

METHOD

  The review follows the PRISMA (preferred reporting items for systematic reviews and meta-analysis) statement guidelines. Three databases (Medline, Web of Science, and Scopus) were searched combining the search terms 'bulimic disorder', 'bulimia nervosa (BN)', 'binge-eating disorder (BED)' with terms referring to cognitive domains (e.g. 'executive functions').

RESULTS

  Thirty-seven studies on people with BN and four on people with BED were selected for review. Overall, sample sizes were relatively small [bulimic disorders: median and range 22 (12-83); HC: 27 (13-172)]. The diversity in methodology precluded a meta-analytical approach. People with a bulimic disorder did not present with a clear neurocognitive profile. Inclusion of salient, disorder-related stimuli (e.g. body weight/shape words) in the neurocognitive paradigms tended to generate differences between people with a bulimic disorder and HC.

CONCLUSION

  Neurocognition in bulimic eating disorders is under researched, and the available evidence is inconclusive. This review outlines strategies for further research in this area.

Eating disorders: progress and challenges

BACKGROUND

Eating disorders are common health problems afflicting mainly female adolescents and young women. They are associated with important physical health and psychosocial morbidity, and carry increased risk of death. Their cause is not yet completely understood and their management is complex, with some patients resisting all available treatments. AIMS OF THIS REVIEW: To provide the readers with an update regarding our knowledge and understanding of eating disorders.

METHODS

Medline database has been used for searching articles on eating disorders published since 1980. The key words used were eating disorders, anorexia nervosa, bulimia nervosa, bulimia, and binge eating. Professional books published during this period has been also reviewed.

CONCLUSIONS

In the last 30 years a substantial improvement has been achieved both in the understanding and management of eating disorders, but many problems still need to be resolved. Three principal priorities should be addressed. First, the actual classification of eating disorders should be revised, since about half the cases seen in clinical practice receive a diagnosis of eating disorder not otherwise specified, and it is common to observe a migration between eating disorder diagnoses. Second, the research on pathogenesis should better clarify the exact role of genetic and environmental risk factors, and how they interact and vary across the development and maintenance of eating disorders. Third, there is an urgent need both to disseminate the few evidence-based treatments available, and to develop more potent treatments for all the eating disorder diagnostic categories.

Therapists' experiences of cognitive remediation therapy for anorexia nervosa: implications for working with adolescents

Cognitive Remediation Therapy (CRT) is a novel intervention developed for adults with anorexia nervosa (AN), which aims to improve "cognitive flexibility" and "holistic processing" thinking styles (Tchanturia et al., 2008; Tchanturia & Hambrook, 2009). The present study uses a qualitative approach to examine therapists' accounts of their work with inpatients suffering with AN. The objective of this study is to gain a broader understanding of how CRT has been implemented and utilized in daily life by this patient group. Therapists' letters were positive and motivational; acknowledging patients for their achievements while outlining some of the difficulties and emotions that patients experienced. Findings highlight that the majority of patients' difficulties related to their metacognitive ability and in transferring the skills to real life. Themes also concerned the processes and stages of CRT, where patients gradually drew skills from the intervention prior to making changes in their own lives. The implications of this approach for working with adolescents with eating disorders are explored. It is hoped that this study will help understanding of how CRT can be used as a treatment for AN; and how it could be developed for future work with young people.

Different Patterns of Emotional Eating and Visuospatial Deficits Whereas Shared Risk Factors Related with Social Support between Anorexia Nervosa and Bulimia Nervosa

OBJECTIVE

Although it is thought that eating disorders result from the interplay of personal and sociocultural factors, a comprehensive model of eating disorders remains to be established. The aim of this study was to determine the extent to which the childhood factors and deficit in visuoperceptual ability contribute to eating disorders.

METHODS

A total of 76 participants - 22 women with anorexia nervosa (AN), 28 women with bulimia nervosa (BN), and 26 healthy women of comparable age, IQ, and years of education - were examined. Neuropsychological tasks were applied to measure the visuoperceptual deficits, viz. the Rey-Osterrieth complex figure test and the group embedded figures test (GEFT). A questionnaire designed to obtain retrospective assessments of the childhood risk factors was administered to the participants.

RESULTS

The women with both AN and BN were less likely to report having supportive figures in their childhood and poor copy accuracy in the Rey-Osterrieth test. The women with AN were more likely to report premorbid anxiety, childhood emotional undereating and showed poor performances in the GEFT. In the final model, the factors independently contributing to the case status were less social support in childhood as a common factor for both AN and BN, and childhood emotional undereating and poor ability in the low-level visuospatial processing for AN.

CONCLUSION

Our results suggest the disturbance in the food-emotion relationship and the deficit in low-level visuospatial processing in people with AN. Lower social support appears to contribute to an increase in vulnerability to both AN and BN.

Neurocircuity of eating disorders

OBJECTIVES

This chapter reviews brain imaging findings in anorexia and bulimia nervosa which characterize brain circuitry that may contribute to the pathophysiology of eating disorders (EDs).

SUMMARY OF RECENT FINDINGS

Recent imaging studies provide evidence of disturbed gustatory processing in EDs which involve the anterior insula as well as striatal regions. These results raise the possibility that individuals with anorexia nervosa have altered appetitive mechanism that may involve sensory, interoceptive, or reward processes. Furthermore, evidence of altered reward mechanisms is supported by studies that suggest that individuals with anorexia nervosa and bulimia nervosa share a trait toward similar anterior ventral striatal pathway dysregulation. This shared trait disturbance of the modulation of reward and emotionality may create a vulnerability for dysregulated appetitive behaviors. However, those with anorexia nervosa may be able to inhibit appetite and have extraordinary self-control because of exaggerated dorsal cognitive circuit function, whereas individuals with bulimia nervosa are vulnerable to overeating when they get hungry, because they have less ability to control their impulses.

FUTURE DIRECTIONS

Current therapeutic interventions have modest success. Better understanding of neurocircuits that may be related to altered appetite, mood, impulse control, and other symptoms underlying the pathophysiology of EDs might improve psychotherapeutic and drug treatment strategies.

"Hunting with a knife and ... fork": examining central coherence in autism, attention deficit/hyperactivity disorder, and typical development with a linguistic task

A local processing bias, referred to as "weak central coherence," has been postulated to underlie key aspects of autism spectrum disorder (ASD). Little research has examined whether individual differences in this cognitive style can be found in typical development, independent of intelligence, and how local processing relates to executive control. We present a brief and easy-to-administer test of coherence requiring global sentence completions. We report results from three studies assessing (a) 176 typically developing (TD) 8- to 25-year-olds, (b) individuals with ASD and matched controls, and (c) matched groups with ASD or attention deficit/hyperactivity disorder (ADHD). The results suggest that the Sentence Completion Task can reveal individual differences in cognitive style unrelated to IQ in typical development, that most (but not all) people with ASD show weak coherence on this task, and that performance is not related to inhibitory control. The Sentence Completion Task was found to be a useful test instrument, capable of tapping local processing bias in a range of populations.

Preliminary evidence for a role for impulsivity in cognitive disinhibition in bulimia nervosa

The present study investigated cognitive disinhibition in bulimia nervosa (BN) and examined whether impulsivity could account for this neuropsychological deficiency. Inhibitory processing of 13 women with BN (16-29 years) was compared against that of 13 healthy control participants matched for age, education, and socioeconomic status on a battery of widely used tasks: Stroop task, Haylings sentence completion test, excluded letter fluency, and Matching Familiar Figures Test. The women were also administered the Barratt Impulsiveness Scale (BIS-11). The BN patients displayed significant impairments on all inhibition measures and posited significantly higher impulsivity scores than the controls. Moreover, controlling for impulsivity reduced the group differences in Stroop color naming and excluded letter fluency to nonsignificance, indicating that poor inhibitory control in BN is at least partly attributable to an impulsive disposition.

Central coherence in eating disorders: a systematic review

BACKGROUND

This review systematically appraised the research evidence for local versus global information processing to test the hypothesis that people with eating disorders (ED) had weak central coherence.

METHOD

Searches on Medline, EMBASE, PsycINFO and ISI Web of Science databases were conducted in November 2006 and subsequently updated in September 2007. Each search was conducted in two steps: (1) neuropsychological tasks measuring central coherence and (2) words related to cognitive functioning in eating disorders. Data were summarized in a meta-analysis if the number of studies for a given test was >5.

RESULTS

Data were extracted from 16 studies. Meta-analyses were conducted for four tasks obtaining moderate effect sizes. The majority of studies found global processing difficulties across the ED spectrum. The results are less clear regarding local processing.

CONCLUSIONS

People with ED have difficulties in global processing. It is less certain as to whether they have superior local processing. Currently, there is insufficient evidence to refute the weak central coherence hypothesis.

Weak central coherence in eating disorders: a step towards looking for an endophenotype of eating disorders

Previous work has found that women with anorexia nervosa and bulimia nervosa have weak coherence. The aim of this study was to examine whether women who had recovered from an eating disorder (ED) also had weak coherence. A total of 42 recovered ED women and 42 healthy women were assessed with a battery of five neuropsychological tests that measure aspects of global or local functioning. The recovered ED group showed superior local processing and poorer global processing than the healthy group. These results are indicative of weak coherence. The finding that weak coherence is a stable characteristic rather than a state effect suggests that it may be an endophenotype for ED.