Cognitive deficits as an endophenotype for anorexia nervosa: an accepted fact or a need for re-examination?

Disentangling cognitive flexibility: a model-based assessment of women with anorexia nervosa

Cognitive flexibility (CF) has been proposed as a potential trait marker in anorexia nervosa (AN), although findings have been inconsistent. To address this inconsistency, we applied a model that distinguishes between three subtypes of CF: task switching, switching sets, and stimulus-response mapping, which we then assessed using a paradigm-based task battery. The aim of the study was to investigate how AN is associated with these three CF subtypes. Thirty-three women with AN and 37 age- and education-matched controls performed a battery of computerized cognitive tasks to assess the three CF subtypes. Compared to the control group, individuals with AN exhibited poorer performance on the task switching and switching sets subtypes, as measured by response time switch cost, but not on the stimulus-response mapping subtype. No differences were found between the groups in response accuracy. Furthermore, switching sets as compared to the task switching and stimulus-response mapping subtypes was found to better explain the differences between the groups. These findings indicate a domain-specific impairment in CF among patients with AN, reflecting deficits observed in subtypes related to the disorder's characteristics, particularly that associated with visual perception. Therefore, CF impairment in AN should not be viewed dichotomously, but rather as a relative impairment that varies depending on the specific CF subtype.

Testing associations between assessments of cognitive flexibility and eating disorder symptoms in adolescent bulimia nervosa

OBJECTIVE

Cognitive rigidity, or difficulty adapting to changing demands, is commonly observed in anorexia nervosa. Less is known, however, about cognitive flexibility (CF) in bulimia nervosa (BN) and, particularly, adolescence. Clarifying this relation and best assessment practices may guide informed clinical decision-making. The current study compared how two measures of CF (i.e., Wisconsin Card Sort Task [WCST] and Trail Making Task [TMT]) relate to BN symptoms among adolescents.

METHODS

Data from a subsample (n = 78) of adolescents with BN were analyzed. Linear and hurdle regressions were used to compare the effects of WCST perseverative errors and TMT performance on Eating Disorder Examination Global Scores, objective binge episodes, and self-induced vomiting episodes (SVEs) at baseline and end-of-treatment (EOT).

RESULTS

Neither CF measure associated with baseline BN symptoms. TMT performance positively associated with the likelihood of engaging in SVEs at EOT (𝛽 = 0.47, p = 0.01, 95% confidence interval [CI] = [0.11-0.84]) and, among adolescents who endorsed ≥1 SVE at EOT, WCST perseverative errors (𝛽 = 0.05, p = 0.005, 95% CI = [0.01-0.08]) positively associated with SVE frequency at EOT.

DISCUSSION

The overall lack of associations between CF and outcomes suggests that cognitive rigidity may not be as relevant to the clinical profile of adolescent BN as for anorexia nervosa. In the few significant associations that emerged, the WCST and TMT uniquely predicted the severity of vomiting at EOT in this sample. Given the lack of CF deficits, future work should aim to test the role of other executive functions (e.g., impulsivity), in addition to CF, to determine which deficits are present in adolescent BN and may predict outcomes.

PUBLIC SIGNIFICANCE

Patients with eating disorders often have difficulties thinking flexibly, which may interfere with their recovery. We tested two ways of measuring flexible thinking in adolescents with BN. Overall, flexible thinking was not associated with symptom-level outcomes. However, less flexible thinking at the start of treatment predicted self-induced vomiting at EOT. If findings are replicable, then assessing and addressing flexible thinking could improve outcomes for adolescents with BN.

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.

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.

Mental flexibility assessment: A research protocol for patients with Parkinson's Disease and Anorexia Nervosa

Mental Flexibility oscillates between adaptive variability in behavior and the capacity to restore homeostasis, linked to mental health. It has recently been one of the most investigated abilities in mental and neurological diseases such as Anorexia nervosa and Parkinson's disease, studied for rigidity or cognitive inflexibility. Patients with anorexia nervosa have rigid cognitive processes about food and weight, which leads to restrictive eating and excessive exercise. People who struggle to adapt their cognitive processes and actions to change their diet and exercise habits may have a harder time recovering from the disorder. On the other hand, research suggests that Parkinson's disease patients may have cognitive flexibility impairments that impair their ability to perform daily tasks and adapt to new environments. Although of clinical interest, mental flexibility lacks theoretical liberalization and unified assessment. This study introduces "IntellEGO" a protocol for a new, multidimensional psychometric assessment of flexibility. This assessment evaluates a person's authentic ability to handle daily challenges using cognitive, emotional, and behavioral factors. Since traditional assessments often focus on one domain, we aim to examine flexibility from multiple angles, acknowledging the importance of viewing people as whole beings with mental and physical aspects. The study protocol includes two assessment phases separated by a rehabilitation period. T0, the acute phase upon admission, and T1, the post-rehabilitation phase lasting 15 days for Parkinson's patients and 4 weeks for eating disorder patients, will be assessed. Neuropsychological performance, self-report questionnaires, psychophysiological measures, and neuroendocrine measures will be collected from Anorexia Nervosa and Parkinson's Disease patients during each study phase. The objective of this procedure is to provide clinicians with a comprehensive framework for conducting meticulous assessments of mental flexibility. This framework considers emotional, cognitive, and behavioral factors, and is applicable to various patient populations.

Intolerable feelings of uncertainty within the body: Associations between interoceptive awareness, intolerance of uncertainty, and body dissatisfaction

BACKGROUND

Adolescence is a period marked by important physical and social changes, which often leads to an increase of body dissatisfaction. Recent studies have shown an association between interoception and body dissatisfaction in female adolescents. One variable that may contribute to the association between interoceptive awareness and body dissatisfaction is intolerance of uncertainty (IU). This study aims to investigate multiple facets of interoceptive awareness, IU, and their relations with body dissatisfaction in adolescent girls.

METHODS

In a cross-sectional study, a convenience sample of 307 adolescent girls (mean age = 17.73; SD = 1.02) was recruited in the Netherlands in 2022. Three questionnaires were completed measuring interoceptive awareness, IU, and body dissatisfaction. A moderation analyses using a multiple hierarchical regression was used to investigate associations between variables.

RESULTS

Correlation analyses indicated that several facets of lower interoceptive awareness (Not distracting, Not worrying and Trusting) were related to higher levels of body dissatisfaction. IU only marginally moderated the relationship between several domains of interoceptive awareness (Notice, Attention regulation and Emotional awareness) and body dissatisfaction.

DISCUSSION

Findings suggest that experiencing bodily signals as ambiguous and uncertain may result in more complex body image issues. Within certain domains of interoceptive awareness, IU may affect the process of appraising bodily signals. Furthermore, adolescent girls who do not feel safe in their body and who find it difficult to distract their thoughts when experiencing pain or discomfort in their body may be particularly at risk for developing more complex body image disturbances and may benefit from interventions improving both interoceptive awareness and IU. Moreover, future research should focus on interoceptive awareness and IU as potential underlying mechanisms for body image issues.

Investigating differences in cognitive flexibility, clinical perfectionism, and eating disorder-specific rumination across anorexia nervosa illness states

INTRODUCTION

Cognitive inflexibility, clinical perfectionism, and eating disorder (ED)-specific rumination are common characteristics reported in anorexia nervosa (AN) and may contribute to the maintenance of the illness. It is suggested that clinical perfectionism and rumination may mediate the relationship between cognitive flexibility and AN pathology; however, research to date has not investigated all these factors together. The aim of the current study was to explore the relationships between these factors and how they may relate to ED symptoms in AN.

METHODS

Participants included 15 women with a current diagnosis of AN, 12 women who had a past diagnosis of AN and were currently weight-restored, and 15 healthy controls (HCs).

RESULTS

The results revealed that participants with both acute and weight-restored AN self-reported poorer cognitive flexibility than HCs, but the groups did not differ in performance on objective assessments of cognitive flexibility. Participants with AN also reported significantly greater clinical perfectionism and ED-specific rumination than HC. A parallel mediation analysis found that ED-specific rumination mediated the relationship between subjective cognitive flexibility and ED symptoms. Further, subjective cognitive flexibility directly influenced ED symptoms. However, the mediation model was not significant for objective cognitive flexibility.

CONCLUSION

The findings of this study have implications for potential treatment barriers and factors which might contribute to the risk of relapse.

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.

MICEmi: A method to identify cognitive endophenotypes of mental illnesses

BACKGROUND

Characterizing neurocognitive endophenotypes of mental illnesses (MIs) could be useful for identifying at-risk individuals, increasing early diagnosis, improving disease subtyping, and proposing therapeutic strategies to reduce the negative effects of the symptoms, in addition to serving as a scientific basis to unravel the physiopathology of the disease. However, a standardized algorithm to determine cognitive endophenotypes has not yet been developed. The main objective of this study was to present a method for the identification of endophenotypes in MI research.

METHODS

For this purpose, a 14-expert working group used a scoping review methodology and designed a method that includes a scoring template with five criteria and indicators, a strategy for their verification, and a decision tree.

CONCLUSIONS

This work is ongoing since it is necessary to obtain external validation of the applicability of the method in future research.

Orthorexia nervosa and executive dysfunction: symptomatology is related to difficulties with behavioral regulation

PURPOSE

This research explored whether orthorexia nervosa is associated with deficits in executive function.

METHODS

A non-clinical sample of participants (n = 405; 80% women, 53% white, mean age = 24, mean body mass index = 25) completed the Orthorexia Nervosa Inventory (ONI) and the Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A).

RESULTS

ONI scores were weakly to moderately correlated with all BRIEF-A scales (p < 0.001 for eight scales, p < 0.05 for one scale), exhibiting the greatest correlations with the scales assessing behavioral regulation: Emotional Control (r = 0.34), Inhibition (r = 0.30), Set Shifting (r = 0.25), and Self-Monitoring (r = 0.28). Hierarchical regression analyses revealed that eight of these nine relationships remained significant (p < 0.001 for five scales including all behavioral regulation scales, p < 0.01 for two scales, p < 0.05 for one scale) after controlling for demographic variables (e.g., gender, body mass index, age, education level) and diagnoses of an eating disorder, obsessive-compulsive disorder, attention deficit/hyperactivity disorder, autism, and learning disability.

CONCLUSION

These findings suggest that, despite unique manifestations, orthorexia and anorexia may possess an overlapping neuropsychological profile marked by deficits in executive function, which may negatively impact daily life.

LEVEL OF EVIDENCE

Level V, descriptive cross-sectional study.

Neuropsychological functioning in adult anorexia nervosa: A meta-analysis

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

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

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

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

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

Evaluation of cognitive impairment in a French sample of patients with restrictive anorexia nervosa: two distinct profiles emerged with differences in impaired functions and psychopathological symptoms

PURPOSE

The cognitive profiles of patients suffering from anorexia nervosa (AN) are currently explored as potential facilitating and/or maintenance factors. Specific data in restrictive AN (AN-R) remain contradictory. This study focused on women with AN-R to evaluate their cognitive functions to develop a more specific cognitive remediation program.

METHODS

Female patients older than 15 years who were suffering from AN-R were recruited in a specialized unit for eating disorder management. Female healthy control (HC) participants were recruited who were matched with AN patients on age. All participants completed a cognitive evaluation (premorbid intelligence quotient (IQ), planning, information processing speed, cognitive flexibility) and a clinical evaluation (impulsivity, anxiety, depression).

RESULTS

A total of 122 participants were included. Patients suffering from AN-R had significant impairment in information processing speed and planning. Patients exhibited significantly better cognitive flexibility than did the HC group when adjustments were made for other cognitive functions and impulsivity. Two distinct subgroups of patients were identified. The first subgroup had more marked cognitive impairment and fewer psychopathological symptoms than did the second subgroup of patients and the HC group.

CONCLUSION

Our results highlight cognitive impairment in patients with AN who had normal premorbid IQ. Two distinct profiles emerge. In clinical practice, these results open up perspectives for the development of more specific cognitive remediation programs (one specific program for cold cognitions and another specific program targeting emotions and hot cognitions). These results warrant confirmation by larger studies with a more specific evaluation of the impact of emotional status. Trial registration NTC02381639, Date of registration. March 6, 2015.

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

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

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

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

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.

Cognitive flexibility in acute anorexia nervosa and after recovery: A systematic review

Difficulties in cognitive flexibility-the ability to adapt effectively to changes in the environment and/or changing task demands-have been reported in anorexia nervosa (AN). However, findings are inconsistent across studies and it remains unclear which specific aspects of cognitive flexibility patients with AN may struggle with. This systematic review aimed to synthesise existing research on cognitive flexibility in AN and clarify differences between patients with acute AN, patients who are weight-restored and patients who are fully recovered from AN. Electronic databases were searched through to January 2020. 3,310 papers were screened and 70 papers were included in the final review. Although adults with acute AN performed worse in perceptual flexibility tasks and self-report measures compared to HCs, they did not exhibit deficits across all domains of cognitive flexibility. Adolescents with acute AN did not differ to HCs in performance on neurocognitive tasks despite self-reporting poorer cognitive flexibility. Overall, significant differences in cognitive flexibility between acute and recovered participants was not evident, though, the findings are limited by a modest number of studies. Recovered participants performed poorer than HCs in some neurocognitive measures, however, results were inconsistent across studies. These results have implications for the assessment of cognitive flexibility in AN and targeted treatment approaches.

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.

Characteristics of autism spectrum disorders are associated with longer duration of anorexia nervosa: A systematic review and meta-analysis

OBJECTIVE

Anorexia nervosa (AN) is associated with neuropsychological characteristics such as impairments in central coherence, cognitive flexibility, and emotion recognition. The same features also manifest in autism spectrum disorders (ASD) and have been suggested to be associated with illness prolongation in AN. The purpose of this meta-analysis was to examine whether pronounced neuropsychological characteristics related to ASD are associated with illness duration in AN.

METHOD

Four databases (Medline, PsycINFO, Scopus, PubMed) were searched for eligible studies. Search terms were (a) "anorexia nervosa" and (b) "cognitive flexibility" or "set-shifting" or "central coherence" or "emotion recognition" or "theory of mind". The final sample consisted of 53 studies. Duration of AN was divided into three categories in order to investigate differences between the groups with varying illness duration. The meta-analysis was performed with Review Manager using a random-effects model.

RESULTS

Deficits in central coherence, cognitive flexibility, and emotion recognition were pronounced among individuals with prolonged AN compared to those with shorter illness duration.

DISCUSSION

A prolonged course of AN appears to be associated with underlying neuropsychological characteristics that are also distinctive to ASD. Neuropsychological impairments may lead to prolonged AN, and prolonged illness may contribute to the subsequent "neurological scar effect," further strengthening these impairments.

Residual eating disorder symptoms and clinical features in remitted and recovered eating disorder patients: A systematic review with meta-analysis

OBJECTIVE

In psychiatry, the presence of residual symptoms after treatment is linked to the definitions of remission and recovery. To identify the presence of residual eating disorder (ED) symptoms and associated non-ED clinical features in remitted and recovered EDs, the current systematic review with meta-analysis was performed.

METHOD

A systematic review was conducted on residual ED symptoms and non-ED clinical features including comorbid psychopathology, neurophysiological functioning, cognitive functioning, and quality of life in ED patients considered remitted or recovered. To examine residual ED symptoms, meta-analyses were performed while considering age, study quality, remission, and recovery criteria strictness as moderators. Sensitivity, publication bias, and heterogeneity analyses were also conducted.

RESULTS

The 64 studies selected for the systematic review underscored the presence of residual ED symptoms in anorexia nervosa (AN) and bulimia nervosa (BN), and impairments and deficits in the additional features examined. From the 64 studies, 31 were selected regarding residual ED symptoms in AN for meta-analysis. Large effect sizes indicated that remitted/recovered AN patients reported significantly lower body mass index (Hedges' g = -0.62[-0.77, -0.46]) and significantly greater symptomatology in terms of ED examination-questionnaire (Hedges'g = 0.86 [0.48,1.23]) and ED inventory (Hedges' g = 0.94[0.64,1.24]) than healthy controls, independently of remission and recovery criteria strictness, age, and study quality.

DISCUSSION

The presence of residual ED symptoms in AN is quantitatively supported, whereas the presence of residual ED symptoms in BN should be further investigated. Data on binge-eating disorder are missing. Future research should use consistent, multicomponent, and standardized comparable indicators of recovery.

General and Eating Disorder Specific Flexibility: Development and Validation of the Eating Disorder Flexibility Index (EDFLIX) Questionnaire

Findings from studies investigating cognitive flexibility in eating disorders (EDs) are inconsistent, and although neuropsychological tests are commonly used to measure these skills, they may not be particularly effective in predicting everyday functioning. Also, extant studies have largely focused on flexibility in anorexia nervosa (AN), with assessments targeting general rather than specific flexibility, and cognitive, rather than behavioral flexibility. Knowledge regarding ED specific flexibility and flexibility in bulimia nervosa (BN) and binge eating disorder (BED) is still scarce. The aim of this study was to develop and validate a novel measure assessing general and ED specific flexibility in a diagnostically diverse sample, and in healthy controls (HCs). A sample of 207 adult individuals with EDs (55% AN, 29% BN, 16% BED) and 288 HCs responded to an online, 51-item, pilot questionnaire on ED specific and general flexibility. In addition, participants completed the shift subscale from the Behavior Rating Inventory of Executive Function Adult version (BRIEF-A), and the Eating Disorder Diagnostic Scale (EDDS). A principal component analysis (PCA) in the clinical sample yielded a 36-item, three-factor solution capturing general flexibility, flexibility related to food and exercise, and flexibility concerning body shape and weight. Results showed that the measure had good to excellent internal consistency, and good convergent validity. A confirmatory factor analysis (CFA) using data from HCs revealed good fit indexes, supporting the original factor solution. A receiver operating characteristics analysis (ROC) demonstrated excellent accuracy in distinguishing scores from those with and without EDs. A cutoff score of 136 yielded the most balanced sensitivity and specificity. Significant differences in general and ED specific flexibility were found between individuals with and without EDs. Overall, HCs achieved the highest flexibility scores, followed by those with BED, BN, and AN. In sum this novel measure, the Eating Disorder Flexibility Index (EDFLIX) questionnaire, was found to be reliable and valid in the assessment of cognitive and behavioral flexibility, with results offering support for the conceptual distinction between general and ED related flexibility. The study also provides strong evidence for the discriminant validity of the EDFLIX with results revealing significant differences in flexibility in people with and without EDs. In addition, significant differences in flexibility also emerged when comparing diagnostic groups, indicating the utility of the assessment instrument for classification purposes.

The improvement in neurocognitive functioning in anorexia nervosa adolescents throughout the integrative model of psychotherapy including cognitive remediation therapy

BACKGROUND

Patients with anorexia nervosa (AN) experience difficulties in neurocognitive functioning in the acute phase of illness which might be related to clinical presentation, but also in the apparently remitted state after weight recovery. Among the most commonly reported persistent deficits is cognitive inflexibility, which can be interpreted as a vulnerability trait or a "neuropsychological scar" reflecting the detrimental effect of prolonged semi-starvation in patients with a long duration of illness. Studies of adolescent samples with a relatively short clinical course may enable avoiding the effect of prolonged illness and help to determine whether neuropsychological deficits are trait or state dependent. The aim of this study is to assess cognitive functioning in adolescents with AN before and after the inpatient treatment programme, including cognitive remediation therapy (CRT).

METHODS

Forty-seven adolescent female inpatients with AN diagnosed according to DSM-5 and fifty healthy female adolescents matched for the education level and age were recruited. The patients underwent a multimodal treatment including a ten-week CRT. The standardized and cross-validated neuropsychological (Trail Making Test - TMT A and B, Color-Word Stroop Task - CWST, Ruff Figural Fluency Test - RFFT) and clinical measurements (Beck Depression Inventory - BDI, Eating Attitude Test - EAT-26, Yale-Brown Obsessive Compulsive Scale - Y-BOCS) were used to assess both clinical (in the acute phase and after partial weight recovery) and control subjects.

RESULTS

Initially, AN patients performed significantly worse compared to the controls, but afterwards, inpatient treatment improvement was noted on all examined measures. In a few subtests (TMT, CWST) performance of AN patients after the programme was still significantly poorer than in HC.

CONCLUSIONS

Cognitive inflexibility in adolescent AN patients, as measured with TMT, CWST, and RFFT tends to improve after therapy. Nevertheless, a few neuropsychological subtests which did not show complete normalization may warrant attention in subsequent studies. Further research including control intervention is needed to conclude whether CRT intervention affects the outcome.

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

BACKGROUND

The aim of this study was to review the existing literature and evaluate whether deficits in set-shifting, central coherence and decision-making persist in individuals recovered from anorexia nervosa (AN-REC).

METHOD

A systematic review approach was used. Literature was identified via searches in PubMed, PsychInfo and Embase database. The main search resulted in 158 articles. After exclusion of 135 articles, 23 articles were included in the review.

RESULTS

The majority of studies on set-shifting showed that set-shifting difficulties persist after recovery. Central coherence might also be trait related, however findings are inconsistent. Few studies have investigated decision-making in AN-REC, however those studies that do exist suggest that decision-making is not impaired in AN-REC.

CONCLUSIONS

Novel treatment strategies based on neuroscience research are emerging, focusing on targeting the underlying mechanisms of the illness, including neuropsychological functioning. Whether these functions are trait or state related could have implications for how they are targeted in treatment.

Executive functioning in adolescent anorexia nervosa: Neuropsychology versus self- and parental-report

There is limited research concerning the relationship between neuropsychological assessment and self-report of executive functioning in adolescent anorexia nervosa (AN); available studies demonstrate only low to moderate correlations. Therefore, this study examines the association between neuropsychological test performance and self-report in AN. Forty adolescent inpatients with AN completed an extensive neuropsychological assessment, including set-shifting, central coherence, and questionnaires assessing executive functioning in daily life (BRIEF-SR). Their parents filled out an analog version (BRIEF-PF). Statistical analyses revealed low to medium positive and negative correlations between neuropsychological measures and BRIEF subscales. Similarly, self- and parental ratings were only slightly positively correlated, with patients scoring significantly higher than their parents on two subscales. The results support previous findings of modest correlations between self-report and performance-based testing and emphasize the importance of a multiple format assessment of executive functioning in adolescent AN.

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

OBJECTIVE

In recent years there has been increasing clinical and empirical interest in neurocognitive functioning in eating disorders (EDs), which has resulted in numerous quantitative and qualitative reviews. However, there has yet to be a comprehensive synthesis or critical review of this literature to identify future directions to advance the field in this area. Therefore the aim of this systematic review of systematic reviews was to (a) characterize the existing literature on neurocognitive functioning in EDs based on recent reviews (i.e., published since 2010), (b) describe related limitations, and (c) suggest avenues for future research to address gaps in the current literature.

METHOD

Electronic databases were queried for reviews of neurocognitive domains (i.e., inhibitory control, decision-making, central coherence, set-shifting, working memory, and attention bias) in EDs, which identified 28 systematic and meta-analytic reviews.

RESULTS

Broadly, the literature indicates deficits across these neurocognitive domains in EDs, though heterogeneity was noted in the magnitude of these effects, which varied to some extent across ED subtypes, sample characteristics, and methodological approaches.

DISCUSSION

While these reviews have generally suggested varying patterns of neurocognitive deficits across EDs, there remain critical limitations regarding the methodological quality of these studies (e.g., the lack of prospective designs, consideration of confounding influences, or examination of interrelationships between neurocognitive domains and relationships between neurocognition and other relevant behavioral constructs). Specifically, we outline 10 key areas that are imperative to address in future research in this area in order to move our field forward.

Differences in set-shifting and central coherence across anorexia nervosa subtypes in children and adolescents

OBJECTIVE

Regarding executive functioning in anorexia nervosa (AN), little is known about differences between the restricting (AN-R) and binge eating/purging (AN-BP) subtypes. Especially for adolescents, there is sparse data. Hence, the current aim is to investigate differences in set-shifting, central coherence, and self-reported executive functioning across adolescent AN subtypes.

METHODS

Ninety AN-R, 21 AN-BP, and 63 controls completed an extensive assessment battery including neuropsychological tests for executive functioning and the self-report questionnaire Behavior Rating Inventory of Executive Functioning.

RESULTS

Patients with AN-R and AN-BP did not differ on neuropsychological measures, and both performed similarly to controls. Behavior Rating Inventory of Executive Functioning scores fell within the normal range with AN subtypes showing mostly comparable ratings. AN-BP patients scored higher on 2 composite indices and the "shift" subscale compared with AN-R.

CONCLUSIONS

The results suggest similar cognitive functioning in adolescent AN subtypes as well as healthy controls. However, more research is needed to draw more general conclusions.

Neurocognitive Impairments Are More Severe in the Binge-Eating/Purging Anorexia Nervosa Subtype Than in the Restricting Subtype

Objective: To evaluate cognitive function impairment in patients with anorexia nervosa (AN) of either the restricting (ANR) or binge-eating/purging (ANBP) subtype. Method: We administered the Japanese version of the MATRICS Consensus Cognitive Battery to 22 patients with ANR, 18 patients with ANBP, and 69 healthy control subjects. Our participants were selected from among the patients at the Kobe University Hospital and community residents. Results: Compared to the healthy controls, the ANR group had significantly lower visual learning and social cognition scores, and the ANBP group had significantly lower processing speed, attention/vigilance, visual learning, reasoning/problem-solving, and social cognition scores. Compared to the ANR group, the ANBP group had significantly lower attention/vigilance scores. Discussion: The AN subtypes differed in cognitive function impairments. Participants with ANBP, which is associated with higher mortality rates than ANR, exhibited greater impairment severities, especially in the attention/vigilance domain, confirming the presence of impairments in continuous concentration. This may relate to the impulsivity, an ANBP characteristic reported in the personality research. Future studies can further clarify the cognitive impairments of each subtype by addressing the subtype cognitive functions and personality characteristics.

Anorexia nervosa and bulimia nervosa: A meta-analysis of executive functioning

OBJECTIVE

Research investigating the link between eating disorder (ED) diagnosis and executive dysfunction has had conflicting results, yet no meta-analyses have examined the overall association of ED pathology with executive functioning (EF).

METHOD

Effect sizes were extracted from 32 studies comparing ED groups (27 of anorexia nervosa, 9 of bulimia nervosa) with controls to determine the grand mean effect on EF. Analyses included effects for individual EF measures, as well as an age-based subgroup analysis.

RESULTS

There was a medium effect of ED diagnosis on executive functioning, with bulimia nervosa demonstrating a larger effect (Hedges's g=-0.70) than anorexia nervosa (g=-0.41). Within anorexia nervosa studies, subgroup analyses were conducted for age and diagnostic subtype. The effect of anorexia nervosa on EF was largest in adults; however, subgroup differences for age were not significant.

CONCLUSIONS

Anorexia and bulimia nervosa are associated with EF deficits, which are particularly notable for individuals with bulimia nervosa. The present analysis includes recommendations for future studies regarding study design and EF measurement.

Neurocognitive functions and social functioning in young females with recent-onset anorexia nervosa and recovered individuals

BACKGROUND

Young individuals with anorexia nervosa (AN) or recovered from AN display impairments of social function. To date, however, it is not clear whether they differ from controls with respect to neurocognitive performance and whether those functions contribute to the compromised social function observed in individuals with AN.

METHODS

We included 43 young females with first-episode AN, 28 individuals recovered from adolescent-onset AN, and 41 control individuals (14-22 yr), all without comorbid autism spectrum disorder. We compared the performance of participants across groups in seven neurocognitive functions relevant to social functioning: set-shifting, local processing, processing speed, working memory, sustained attention, verbal memory, and verbal abstraction. Further, we tested the association between neurocognitive function and social function, measured by Autism Diagnostic Observation Schedule (ADOS), with an ordinal logistic regression model.

RESULTS

First, participants did not differ on any neurocognitive function across groups. Second, only the neurocognitive function "verbal memory" was significantly associated with social function. Higher performance in verbal memory was associated with lower odds of impaired social function. Diagnostic group remained a significant factor, but the absence of an interaction between group and neurocognitive performance indicated that the association between verbal memory and social function was independent of group membership.

CONCLUSION

Young individuals with AN and those recovered from AN did not differ from controls with respect to neurocognitive performance. Verbal memory was associated with social function in all groups.

Evidence for Thalamocortical Circuit Abnormalities and Associated Cognitive Dysfunctions in Underweight Individuals with Anorexia Nervosa

Anorexia nervosa (AN) is characterized by extremely low body weight resulting from pathological food restriction, and carries a mortality rate among the highest of any psychiatric illness. AN, particularly during the acute, underweight state of the illness, has been associated with abnormalities across a range of brain regions, including the frontal cortex and basal ganglia. Few studies of AN have investigated the thalamus, a key mediator of information flow through frontal-basal ganglia circuit loops. We examined both thalamic surface morphology using anatomical MRI and thalamo-frontal functional connectivity using resting-state functional MRI. Individuals with AN (n=28) showed localized inward deformations of the thalamus relative to healthy controls (HC, n=22), and abnormal functional connectivity between the thalamus and the dorsolateral and anterior prefrontal cortices. Alterations in thalamo-frontal connectivity were associated with deficits in performance on tasks probing cognitive control (Stroop task) and working memory (Letter-Number Sequencing (LNS) task). Our findings suggest that abnormalities in thalamo-frontal circuits may have a role in mediating aspects of cognitive dysfunction in underweight individuals with AN.

Literature Review of Cognitive Neuroscience and Anorexia Nervosa

Studies published between the beginning of 2013 and May 2015 on the neuropsychological functioning of patients with anorexia nervosa compared with healthy participants framed in the context of the Research Domain Criteria matrix identifies evidence for functional differences in three domains: Negative Valance Systems-negative attentional biases and lack of neural responsivity to hunger; Cognitive Systems-limited congruence between clinical and cognitive performance, poorer non-verbal than verbal performance, altered attentional styles to disorder related stimuli, perceptual processing impairment in discriminating body images, weaknesses in central coherence, set shifting weaknesses at low weight status, decision-making weaknesses, and greater neural resources required for working memory; Systems for Social Processes-patients appear to have a different attentional response to faces, and perception and understanding of self and others. Hence, there is evidence to suggest that patients with anorexia nervosa have a specific neuropsychological performance style across tasks in three domains of functioning. Some current controversies and areas for future development are identified.

Sensory modulation disorder symptoms in anorexia nervosa and bulimia nervosa: A pilot study

OBJECTIVE

Individuals with anorexia nervosa (AN) and bulimia nervosa (BN) may exhibit reduced ability to modulate sensory, physiological, and affective responses. The aim of the present study is to assess sensory modulation disorder (SMD) symptoms in patients with AN and BN.

METHOD

We assessed female adolescent and young adult inpatients with restrictive type anorexia nervosa (AN-R; n = 20) and BN (n = 20) evaluated in the acute stage of their illness, and 27 female controls. Another group of 20 inpatients with AN-R was assessed on admission and discharge, upon achieving their required weight. Participants completed standardized questionnaires assessing the severity of their eating disorder (ED) and the sensory responsiveness questionnaire (SRQ).

RESULTS

Inpatients with AN-R demonstrated elevated overall sensory over-responsiveness as well as elevated scores on the taste/gustatory, vestibular/kinesthetic and somatosensory/tactile SRQ modalities compared with patients with BN and controls. Significant correlations between the severity of sensory over-responsiveness and ED-related symptomatology were found in acutely-ill patients with AN-R and to a lesser extent, following weight restoration. Elevated sensory over-responsiveness was retained in weight-restored inpatients with AN-R. Inpatients with BN demonstrated greater sensory under-responsiveness in the intensity subscale of the SRQ, but not in the frequency and combined SRQ dimensions.

DISCUSSION

Female inpatients with AN-R exhibited sensory over-responsiveness both in the acute stage of their illness and following weight restoration, suggesting that sensory over-responsiveness may represent a trait related to the illness itself above and beyond the influence of malnutrition. The finding for sensory under-responsiveness in BN is less consistent.

Does depression matter in neuropsychological performances in anorexia nervosa? A descriptive review

OBJECTIVE

This review aims to examine the impact of depressive symptoms on the assessment of cognitive flexibility, central coherence, and decision-making in individuals with anorexia nervosa (AN).

METHOD

An online search was carried out using PubMed and PsycInfo. Articles were selected for review if they were published in English between 1990 and 2014 and used the Wisconsin Card Sorting Test, the Trail Making Task parts A and B, the Brixton Test, the Rey-Osterrieth Complex Figure Test, and/or the Iowa Gambling Task.

RESULTS

Sixty-two studies were included. Thirty (48%) of the studies statistically assessed the association between depression and neurocognition in AN versus healthy controls. Where significant correlations were found, it became clear that the more serious the depression, the greater the neuropsychological impairment. Only six (10%) studies examined whether increased depressive symptoms were able to eliminate the differences between individuals with AN and healthy controls, and one study found that depressive symptoms did eliminate group differences in cognitive flexibility and decision-making.

DISCUSSION

Only a subgroup of articles on neuropsychology in AN adjusted for depression. However, given the role of depression that some articles suggest, future studies should pay closer attention to the evaluation of this potential confounder.

Systematic review of evidence for different treatment settings in anorexia nervosa

AIM: To compare outcomes in anorexia nervosa (AN) in different treatment settings: inpatient, partial hospitalization and outpatient.

METHODS: Completed and published in the English language, randomized controlled trials comparing treatment in two or more settings or comparing different lengths of inpatient stay, were identified by database searches using terms “anorexia nervosa” and “treatment” dated to July 2014. Trials were assessed for risk of bias and quality according to the Cochrane handbook by two authors (Madden S and Hay P) Data were extracted on trial quality, participant features and setting, main outcomes and attrition.

RESULTS: Five studies were identified, two comparing inpatient treatment to outpatient treatment, one study comparing different lengths of inpatient treatment, one comparing inpatient treatment to day patient treatment and one comparing day patient treatment with outpatient treatment. There was no difference in treatment outcomes between the different treatment settings and different lengths of inpatient treatment. Both outpatient treatment and day patient treatment were significantly cheaper than inpatient treatment. Brief inpatient treatment followed by evidence based outpatient care was also cheaper than prolonged inpatient care for weight normalization also followed by evidence based outpatient care.

CONCLUSION: There is preliminary support for AN treatment in less restrictive settings but more research is needed to identify the optimum treatment setting for anorexia nervosa.

Decision making, central coherence and set-shifting: a comparison between Binge Eating Disorder, Anorexia Nervosa and Healthy Controls

BACKGROUND

Several studies have investigated the cognitive profile in patients with Anorexia Nervosa (AN) and Bulimia Nervosa (BN); on the contrary few studies have evaluated it in patients with Binge Eating Disorder (BED). The purpose of this study was to compare decision making, central coherence and set-shifting between BED and AN patients.

METHODS

A battery of neuropsychological tests including the Iowa Gambling Task (IGT), the Rey-Osterrieth Complex Figure Test (RCFT), the Wisconsin Card Sorting Test (WCST), the Trial Making Task (TMT) and the Hayling Sentence Completion Task (HSCT) were administered in a sample of 135 women (45 AN, 45 BED, 45 Healthy Controls [HC]). Furthermore, Beck Depression Inventory (BDI) was administered to evaluate depressive symptoms. Years of education, age, Body Mass Index (BMI) and depression severity were considered as covariates in statistical analyses.

RESULTS

BED and AN patients showed high rates of cognitive impairment compared to HC on the domains investigated; furthermore, the cognitive profile of BED patients was characterised by poorer decision making and cognitive flexibility compared to patients with AN. Cognitive performance was strongly associated with depressive symptoms.

CONCLUSIONS

In the present sample, two different neurocognitive profiles emerged: a strong cognitive rigidity and a central coherence based on the details was predominant in patients with AN, while a lack of attention and difficulty in adapting to changes in a new situation seemed to better describe patients with BED. The knowledge of the different cognitive profiles of EDs patients may be important for the planning their psychotherapeutic intervention.

Are poor set-shifting abilities associated with a higher frequency of body checking in anorexia nervosa?

BACKGROUND

The rigid and obsessional features of anorexia nervosa (AN) have led researchers to explore possible underlying neuropsychological difficulties. Numerous studies have demonstrated poorer set-shifting in patients with AN. However, due to a paucity of research on the connection between neuropsychological difficulties and the clinical features of AN, the link remains hypothetical. The main objective of this study was to explore the association between set-shifting and body checking.

METHODS

The sample consisted of 30 females diagnosed with AN and 45 healthy females. Set-shifting was assessed using the Wisconsin Card Sorting Test (WCST) and frequency of body checking was assessed using the Body Checking Questionnaire (BCQ).

RESULTS

The analysis showed no significant correlations between any of the WCST scores and the BCQ.

CONCLUSION

The results suggest that there is no association between set-shifting difficulties and frequency of body checking among patients with AN. An alternative explanation could be that the neuropsychological measure included in this study is not sensitive to the set-shifting difficulties observed in clinical settings. We recommend that future studies include more ecologically valid measures of set-shifting in addition to standard neuropsychological tests.