Neuropsychology of eating disorders: 1995-2012

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

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

Executive dysfunction in eating disorders: Relationship with clinical features

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

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.

The perception of food size and food shape in anorexia nervosa

Visual perception of food size and shape in anorexia nervosa (AN) is an understudied topic, notwithstanding its relevance in approaching food, key-element in weight restoration. In addition, it is unclear how visual perception in AN is related to the age and the duration of illness. Here, we compared patients with AN to healthy controls (HCs) on their spatial resolution, biases in perceived food size, and holistic processing of food shape. A total of 122 participants were enrolled: 48 adolescents (27 AN and 21 HCs) and 74 adults (33 AN and 41 HCs). Participants at two academic sites (Israel and Italy) completed measures of psychopathology and experiments measuring visual resolution (Just Noticeable Difference), biases in food-size perception (Points of Subjective Equality), and holistic processing of food shape (indicated by the height-width illusion). Adolescents and adults with AN differed in the duration of illness and body mass index but showed comparable eating psychopathology and body measures. Patients with AN showed preserved visual resolution but distorted perception of food size, perceiving food as bigger than non-food objects, in both age groups. Patients with AN, both adolescents and adults, also processed food stimuli in a more analytic fashion, and were immune to the height-width illusion. The preserved perception of non-food stimuli in AN coupled with biases in food-size perception and in analytic processing of food shape highlight patients' real-world difficulties in approaching food. Future treatments on AN may consider taking these differences into account.

Attentional bias in eating disorders: A meta-review

OBJECTIVE

This meta-review summarizes and synthesizes the most reliable findings regarding attentional bias in eating disorders across paradigms and stimulus types and considers implications for theory and future research.

METHOD

Four databases were systematically searched, along with reference lists of included reviews, yielding 15 systematic reviews (four of which were also meta-analyses). The quality of each review was appraised using the AMSTAR-2.

RESULTS

Key findings from systematic reviews are summarized, organized by paradigm and stimulus type.

DISCUSSION

The authors synthesize evidence from the highest-quality studies. There is evidence for attentional avoidance and vigilance in eating disorders depending on stimulus properties (low vs. high-calorie food; high-body mass vs. low-body mass index photos of others) and attentional avoidance of food stimuli in those with anorexia nervosa. Sad mood induction may generate attentional bias for food in those with binge-eating disorder. There may also be attentional bias to general threat in eating disorder samples. This meta-review concludes that most systematic reviews in this field are low in quality and summarizes the main areas that could be improved upon in future reviews. Implications of this study's findings for theory and intervention research are also discussed.

Cognitive Function in Adults with Enduring Anorexia Nervosa

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

Executive functioning and spatial processing in anorexia nervosa: an experimental study and its significance for the allocentric lock theory

PURPOSE

The allocentric lock theory (ALT) suggests that people with eating disorders have difficulties in multisensory integration in two reference frames-egocentric and allocentric, whereby the egocentric, but not allocentric, is impaired. This leads to a distorted body image that contributes to the development and maintenance of the disorder. The current study aimed to explore a facet of the ALT, namely, the visuo-spatial aspect, and its relation to cognitive flexibility in patients with anorexia nervosa (AN).

METHODS

Fifty-five participants took part in the study: 20 AN patients and 35 controls, matched by age and education. The object perspective taking test (OPTT) and the mental rotation test (MRT), tapping egocentric and allocentric representations, respectively, and a set-shifting task were administered. The brief symptom inventory was used to measure overall levels of distress.

RESULTS

AN patients showed higher level of distress. They performed poorer on the OPTT and set-shifting task but not on the MRT. The OPTT and MRT were correlated for controls but not for AN patients, while the set-shifting task and body mass index were associated with the OPTT but not with the MRT for the AN patients.

CONCLUSIONS

The findings support the ALT by demonstrating impaired visual egocentric representations and intact allocentric visual functions in AN patients, with cognitive flexibility associated only with the egocentric frame. Therefore, egocentric frame impairment in AN patients may be influenced by visual perception and cognitive flexibility deficiency.

LEVEL OF EVIDENCE

Level III: case-control analytic study.

Decision-Making, Impulsiveness and Temperamental Traits in Eating Disorders

OBJECTIVE

To explore decision-making, impulsiveness and temperamental traits in patients suffering from eating disorders (EDs), as compared with healthy controls (HC).

METHOD

Fifty-one patients affected by ED (fourteen with anorexia restricting subtype, AN-R; fourteen with bulimia, BN; thirteen with anorexia bingeing/purging subtype, AN-BP; ten with binge-eating disorder, BED) and twenty-eight HC. The patients, recruited at the Section of Psychiatry of the University of Pisa (Italy, were evaluated with a battery of neuropsychological questionnaires, including the IOWA Gambling Task (IGT), the Barratt Impulsiveness Scale (BIS-11), the Temperament and Character Inventory (TCI), the Frontal Assessment Battery (FAB) and the Hamilton Depression Rating Scale (HAM-D).

RESULTS

The results indicated that AN-R, AN-BP and BN patients showed poorer IGT performances than HC (p < .05), while BED performances were similar to those of HC. IGT scores suggested the existence of similarities in decision-making performances of AN-BP and BN patients, as they performed differently from HC starting from block 3 (F(16.2)=1.7). In addition, differences between AN-BP/BN and AN-R patients were detected, given that they performed differently starting from block 4. As far as BIS-11 is concerned, AN-BP and BN patients reached the highest BIS total scores, when compared with the other groups. Further, they shared similar temperamental and impulsiveness profiles, as demonstrated by their BIS-11 'motor impulsiveness' scores, and by their TCI 'novelty seeking', 'reward dependence' and 'persistence' dimensions. The post-hoc analyses revealed that both AN groups (namely, AN-R and AN-BP) scored significantly lower than HC on the FAB. No patients fulfilled the criteria for the diagnosis of a current major depression.

CONCLUSIONS

Decision-making deficits are common in EDs. In AN-R these seem related to cognitive styles, while in AN-BP and BN patients with temperament features and impulsiveness traits.

Scrutinizing Domains of Executive Function in Binge Eating Disorder: A Systematic Review and Meta-Analysis

BACKGROUND

Cognitive deficits are implicated in theoretical explanatory models for binge eating disorder (BED). Furthermore, evidence suggest that alterations in executive function may underlie symptoms in BED. The current systematic review and meta-analysis provides an update on executive functioning in individuals with BED.

METHODS

Literature searches (up to November 2019) were conducted in electronic databases combining binge eating or BED with executive functions. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines was used. Studies of any design comparing adults with BED with those without BED in executive function domains were selected. Methodological quality of studies was based on the Newcastle-Ottawa scale.

RESULTS

Of 1,983 citations identified, 28 case-control studies met inclusion criteria for this review. Six meta-analyses that examined four domains (decision-making, cognitive flexibility, inhibitory control, and working memory) were conducted. The only meta-analysis to show a significant difference in executive functioning between BED and obese controls was working memory (SMD = 0.32, 95% IC: -0.60, -0.03; p = 0.028), with an effect size of small magnitude. Qualitative inspection of the literature indicated mixed findings for control inhibition, decision making and cognitive flexibility in individuals with BED compared to controls (obese or normal weight). In addition, people with BED showed poorer problem solving performance, but similar planning abilities to obese controls.

CONCLUSIONS

Individuals with BED were found to show worse performance on working memory tasks compared to obese individuals without the disorder. The findings did not provide definitive evidence of alterations in other aspects of executive functioning. Interest in executive functioning in people with BED is increasing but is limited by insufficient data from small studies with varied methodology. Future studies should focus on using similar tests and outcome measures, in order to enable more pertinent comparisons across studies.

The multidisciplinary therapy in binge eating disorder is able to influence the interdaily stability and sleep quality?

We have recently shown that rest-activity circadian rhythm significantly differed in women with Binge Eating Disorder (BED) compared to the Ctrl group. In details, patients with BED exhibited significantly reduced levels of MESOR and Amplitude with respect to the Ctrl group. In addition, in this previous study, the results of the actigraphic sleep monitoring provided no evidence of differences in sleep parameters between the two groups. We expanded the original sample obtaining a total of 28 volunteered women, 14 BED women, and 14 Ctrl. We recorded in all 28 participants a 5-day actigraphic monitoring to detect the rhythmometric parameters, interdaily stability, intradaily variability, L5, M10, and sleep parameters. During the study, BED's women group kept an individual multidisciplinary therapy lasting five weekly days, from Monday to Friday, consisting in cognitive-behavioral therapy and nutritional program, administered in outpatient care from 8:00 a.m. at 5:00 p.m. The combination of both our previous and current study supports the conclusion that the sleep quality of the BED group is significantly better compared to Ctrl. The non-parametric indexes showed how interdaily stability, significantly correlated to sleep efficiency, was higher in BED group compared to the Ctrl group, indicating a better synchronization of rest-activity circadian rhythm. In conclusion, the maintenance of a regular lifestyle, such as imposed by the multidisciplinary therapy, is important to avoid alterations in the sleep-wake cycle, particularly in patients with eating disorders.

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.

Cognitive impairment in eating disorder patients of short and long-term duration: a case-control study

Introduction: Several studies have noted the potentially negative effect of eating disorders (ED) on cognitive performance. Objective: To compare the impact of the duration of abnormal eating behaviors on cognitive performance in a sample of people with short- and long-term eating disorders and in two control groups matched for age. Method: The neuropsychological performance of 82 women diagnosed with an eating disorder were compared with two control groups from the community of 66 healthy women. Time of duration of the disorder was less than two years in half of the clinical sample, and more than 10 years in the other half. The following instruments were used to measure neuropsychological performance: the Matrix Test, the Stroop task, the Trail-Making Test, the Tower of London Test, the Posner Spatial Task, the Rey's Complex Figure, the Wechsler Vocabulary Test, and the Hayling Completion Test. Results: It showed that persons with long-term ED presented more impaired neuropsychological profiles, but not in all areas. In contrast, the short-term ED group presented similar profiles to the control groups. Discussion: This study highlights the positive association between cognitive impairment and time of evolution of ED, above all in perceptual measures and non-verbal memory. Considering the effect of the evolution of ED cognitive performance (especially in long-term patients) may further our understanding of the development of the disorder and the factors that may favor its persistence.

Temporal Processing of Joyful and Disgusting Food Pictures by Women With an Eating Disorder

The present study used the presentation of food pictures and judgements about their duration to assess the emotions elicited by food in women suffering from an eating disorder (ED). Twenty-three women diagnosed with an ED, namely anorexia (AN) or bulimia nervosa (BN), and 23 healthy controls (HC) completed a temporal bisection task and a duration discrimination task. Intervals were marked with emotionally pre-rated pictures of joyful and disgusting food, and pictures of neutral objects. The results showed that, in the bisection task, AN women overestimated the duration of food pictures in comparison to neutral ones. Also, compared to participants with BN, they perceived the duration of joyful food pictures as longer, and tended to overestimate the duration of the disgusting ones. These effects on perceived duration suggest that AN women experienced an intense reaction of fear when they were confronted to food pictures. More precisely, by having elevated the arousal level and activated the defensive system, food pictures seemed to have speeded up the rhythm of the AN participants’ internal clock, which led to an overestimation of images’ duration. In addition, the results revealed that, in both tasks, ED women presented a lower temporal sensitivity than HC, which was related to their ED symptomatology (i.e., BMI, restraint and concern) and, particularly, to their weaker cognitive abilities in terms of attention, processing speed and working memory. Considered all together, the findings of the present experiment highlight the role of fear and anxiety in the manifestations of AN and point out the importance of considering non-temporal factors in the interpretation of time perception performance.

Rest-activity circadian rhythm and sleep quality in patients with binge eating disorder

Recent findings suggest that altered rest-activity circadian rhythms (RARs) are associated with a compromised health status. RARs abnormalities have been observed also in several pathological conditions, such as cardiovascular, neurological, and cancer diseases. Binge eating disorder (BED) is the most common eating disorder, with a prevalence of 3.5% in women and 2% in men. BED and its associate obesity and motor inactivity could induce RARs disruption and have negative consequences on health-related quality of life. However, the circadian RARs and sleep behavior in patients with BED has been so far assessed only by questionnaires. Therefore, the purpose of this study was to determine RARs and sleep parameters by actigraphy in patients with BED compared to a body mass index-matched control group (Ctrl). Sixteen participants (eight obese women with and eight obese women without BED diagnosis) were recruited to undergo 5-day monitoring period by actigraphy (MotionWatch 8®, CamNtech, Cambridge, UK) to evaluate RARs and sleep parameters. In order to determine the RARs, the actigraphic data were analyzed using the single cosinor method. The rhythmometric parameters of activity levels (MESOR, amplitude and acrophase) were then processed with the population mean cosinor. The Actiwatch Sleep Analysis Software (Cambridge Neurotecnology, Cambridge, UK) evaluated the sleep patterns. In each participant, we considered seven sleep parameters (sleep onset: S-on; sleep offset: S-off; sleep duration: SD; sleep latency: SL; movement and fragmentation index: MFI; immobility time: IT; sleep efficiency: SE) calculated over a period of five nights. The population mean cosinor applied to BED and Ctrl revealed the presence of a significant circadian rhythm in both groups (p < 0.001). The MESOR (170.0 vs 301.6 a.c., in BED and Ctrl, respectively; p < 0.01) and amplitude (157.66 vs 238.19 a.c., in BED and Ctrl, respectively p < 0.05) differed significantly between the two groups. Acrophase was not different between BED and Ctrl, as well as all sleep parameters. Both groups displayed a low level of sleep quality (SE 80.7% and 75.7% in BED and Ctrl, respectively). These data provided the first actigraphy-based evidence of RARs disruption and sleep behavior disorder in patients with BED. However, while sleep disorders could be reasonably ascribed to overweight/obesity and the related lower daily physical activity, RARs disruption in this pathology should be ascribed to factors other than reduced physical activity. The circadian timing approach can represent a novel potential tool in the treatment of patients with eating disorders. These data provide exploratory evidence of behavioral association in a small population of patients that, if confirmed in a wider number of subjects and across different populations, may lead to a revision and enhancement of interventions in BED patients.

Similarities and Differences of Neuropsychological Profiles in Children and Adolescents with Anorexia Nervosa and Healthy Controls Using Cluster and Discriminant Function Analyses

OBJECTIVE

This study aimed to identify discrete neuropsychological profiles and their relationship to clinical symptoms in 253 female children and adolescents with anorexia nervosa (AN) and 170 healthy controls (HCs) using a standardised neuropsychological assessment battery.

METHOD

Hierarchical cluster analysis was used to identify the optimum number of clusters, and participants were assigned using K-means cluster analysis. Confirmatory discriminant function analysis determined which combination of neuropsychological variables best distinguished the clusters.

RESULTS

Three distinct clusters in the AN sample emerged- AN cluster 1 (19%) - "neuropsychologically low average to average"; AN cluster 2 (33%) - "verbal/visuo-spatial discrepancy"; and AN cluster 3 (48%) - "verbally strong and neuropsychologically average to high average". Two distinct clusters in HCs were identified. HC cluster 1 (48%) demonstrated poor visuo-spatial memory scores and high verbal fluency scores, whilst HC cluster 2 (52%) scored within the average range on all neuropsychological tasks. Neuropsychological performance was associated with clinical symptoms of body mass index centile, Eating Disorder Examination subscale and global score, anxiety, depression and obsessions, and compulsions between the AN and HC groups. However, niether significant differences emerged between AN clusters only nor HC clusters only at the post-hoc level.

DISCUSSION

An underlying neuropsychological heterogeneity may exist in AN. We encourage future studies to investigate whether the identified profiles and their association with clinical characteristics are replicable. We cautiously suggest that neuropsychological profiling may have potential to both inform future research and have possible clinical benefits through individually tailored treatment strategies.

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.

Functional connectivity correlates of response inhibition impairment in anorexia nervosa

Anorexia nervosa (AN) is a disorder characterized by high levels of cognitive control and behavioral perseveration. The present study aims at exploring inhibitory control abilities and their functional connectivity correlates in patients with AN. Inhibitory control - an executive function that allows the realization of adaptive behavior according to environmental contingencies - has been assessed by means of the Stop-Signal paradigm. The study involved 155 patients with lifetime AN and 102 healthy women. A subsample underwent resting-state functional magnetic resonance imaging and was genotyped for COMT and 5-HTTLPR polymorphisms. AN patients showed an impaired response inhibition and a disruption of the functional connectivity of the ventral attention circuit, a neural network implicated in behavioral response when a stimulus occurs unexpected. The 5-HTTLPR genotype appears to significantly interact with the functional connectivity of ventral attention network in explaining task performance in both patients and controls, suggesting a role of the serotoninergic system in mechanisms of response selection. The disruption of the ventral attention network in patients with AN suggests lower efficiency of bottom-up signal filtering, which might be involved in difficulties to adapt behavioral responses to environmental needs. Our findings deserve further research to confirm their scientific and therapeutic implications.

Cognitive remediation therapy for eating disorders

PURPOSE OF REVIEW

This review compares the literature on cognitive remediation therapy (CRT) for eating disorders with findings in the field of schizophrenia, and discusses future directions for CRT for eating disorders.

RECENT FINDINGS

First studies using a randomized controlled trial design show the added value of CRT for eating disorders. Patients reported lessened symptoms and further improvements in quality of life and cognitive flexibility. Furthermore, the acceptability of the intervention was good and attrition rates for CRT itself were low. Research into the use of cognitive remediation for schizophrenia is extensive and the results on global cognition appeared to be robust at post-treatment and durable at follow-up, with small to medium effect sizes. Recent articles within the field of schizophrenia emphasize the necessity of intrinsic motivation to translate cognitive gains into actual changes in everyday life.

SUMMARY

A next step is to examine the impact of CRT for eating disorders on motivation. It is also important to focus on the transdiagnostic use of CRT, considering the overlap in cognitive inefficiencies between eating disorders. Another important step may be to develop effective personalized methods of CRT by taking into account individual differences in cognitive processes most relevant to improvement in outcome.

Verbal Versus Figural Fluency Tests in Currently Ill and Weight Restored Anorexia Nervosa Patients

Fluency tests allow domain-specific assessment of verbal and non-verbal executive functions (EF) comparison and also enable utilizing of both quantitative and qualitative scoring methods. Thirty-five currently ill anorexia nervosa patients (PANs), 33 weight-restored patients (WRAN) and 47 healthy controls (HCs) were administered the word fluency test and the five-point test. Results show that WRANs tended to perseverate more than HCs in the verbal-fluency test. In addition, PANs produced significantly less correct figures and perseverated more than HCs and WRANs; HCs used more strategy methods than PANs and WRANs. Additionally, a positive correlation was found in the HC group between the total number of words in the verbal phonemic test and the number of designs produced and the number of correct designs. No such correlations were found in both anorexia groups. In conclusion, there is a differentiation between verbal and non-verbal EF in PANs and WRANs, showing a deficiency in the non-verbal domain. These findings may contribute to our understanding of the cognitive nature of the disorder.

Yoga, bioenergetics and eating behaviors: A conceptual review

Yoga is an ancient oriental discipline that emerged from mystical and philosophical concepts. Today it is practiced in the west, partly due to the promotion of its benefits to improve the lifestyle and overall health. As compared to non-Hatha Yoga (HY) practitioners, healthier and better-eating patterns have been observed in those who practice it. Agreement with the brought benefits, HY can be used as a therapeutic method to correct abnormal eating behaviors (AEB), obesity, and some metabolic diseases. However, the energy expenditure during traditional protocols of HY is not high; hence, it is not very effective for reducing or maintaining body weight or to improve cardiovascular conditioning. Even so, several observational studies suggest significant changes in eating behaviors, like a reduction in dietary fat intake and increments in that of fresh vegetables, whole grains and soy-based products, which in turn may reduce the risk for cardiovascular diseases. Given the inconsistency of the results derived from cross-sectional studies, more case–control studies are needed to demonstrate the efficacy of HY as an alternative method in the clinical treatment of disordered eating and metabolic diseases.

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.

Clinical investigation of set-shifting subtypes in anorexia nervosa

While evidence continues to accumulate on the relevance of cognitive inflexibility in anorexia nervosa (AN), its clinical correlates remain unclear. We aimed at examining the relationship between set-shifting and clinical variables (i.e., eating psychopathology, depression, and personality) in AN. Ninety-four individuals affected by AN and 59 healthy controls (HC) were recruited. All participants were assessed using: Eating Disorders Inventory-2 (EDI-2), Temperament and Character Inventory (TCI), Beck Depression Inventory (BDI), and Wisconsin Card Sorting Test (WCST). The AN group scored worse than HCs on set-shifting. According to their neuropsychological performances, AN patients were split into two groups corresponding to poor (N=30) and intact (N=64) set-shifting subtypes. Interoceptive awareness, impulse regulation, and maturity fears on the EDI-2 and depression on the BDI differed across all groups (HC, intact, and poor set-shifting subtype). Self-directedness on the TCI differed significantly among all groups. Cooperativeness and reward dependence differed instead only between HC and AN poor set-shifting subtype. After controlling for depression, only interoceptive awareness remained significant with reward dependence showing a trend towards statistical significance. These findings suggest that multiple clinical variables may be correlated with set-shifting performances in AN. The factors contributing to impaired cognitive inflexibility could be more complex than heretofore generally considered.

The brain-gut axis in health and disease

The interaction between the brain and the gut has been recognized for many centuries. This bidirectional interaction occurs via neural, immunological and hormonal routes, and is important not only in normal gastrointestinal function but also plays a significant role in shaping higher cognitive function such as our feelings and our subconscious decision-making. Therefore, it remains unsurprising that perturbations in normal signalling have been associated with a multitude of disorders, including inflammatory and functional gastrointestinal disorders, and eating disorders.

Psychopathological and personality traits underlie decision making in recent onset medication naïve anorexia nervosa: a pilot study

The Iowa Gambling Task (IGT) analyzes the ability of participants to sacrifice immediate rewards in view of a long term gain. Anorexia Nervosa (AN) in addition to weight loss and body image disturbances is also characterized by the tendency to make decisions that may result in long-term negative outcomes. Studies that analyzed IGT performance in patients with AN were not consistent with each other. Fifteen adolescents with AN and 15 matched controls carried out IGT after being clinically and neuropsychologically evaluated. An interesting generalized estimating equation approach showed that four independent clinical variables, and not the group, explained IGT performances, such as blocks repetition, anxiety, psychogenic eating disorders and self transcendence. The impairment of decision making is not related to the diagnosis of AN, but it is driven by high levels of anxiety and self transcendence. Instead, some psychogenic eating disorders traits, related to illness severity, positively affected IGT performance in the whole sample. IGT impairment in AN found by prior studies could be related to these clinical features which are not always taken into account.

Selective cognitive empathy deficit in adolescents with restrictive anorexia nervosa

BACKGROUND

A growing, but conflicting body of literature suggests altered empathic abilities in subjects with anorexia nervosa-restricting type (AN-R). This study aims to characterize the cognitive and affective empathic profiles of adolescents with purely AN-R.

METHODS

As part of a standardized clinical and research protocol, the Interpersonal Reactivity Index (IRI), a valid and reliable self-reported instrument to measure empathy, was administered to 32 female adolescents with AN-R and in 41 healthy controls (HC) comparisons, matched for age and gender. Correlational analyses were performed to evaluate the links between empathy scores and psychopathological measures.

RESULTS

Patients scored significantly lower than HC on cognitive empathy (CE), while they did not differ from controls on affective empathy (AE). The deficit in CE was not related to either disease severity nor was it related to associated psychopathology.

CONCLUSION

These results, albeit preliminary, suggest that a dysfunctional pattern of CE capacity may be a stable trait of AN-R that should be taken into account not only for the clinical management, but also in preventive and therapeutic intervention.