Perception of emotion and bilateral advantage in women with eating disorders, their healthy sisters, and nonrelated healthy controls

No association between alexithymia and emotion recognition or theory of mind in a sample of adolescents enhanced for autistic traits

LAY ABSTRACT

Alexithymia is a sub-clinical condition characterised by difficulties identifying and describing one's own emotions, which is found in many, but not all autistic people. The alexithymia hypothesis suggests that certain aspects of socio-cognitive functioning typically attributed to autism, namely difficulties in emotion recognition, might be better explained by often co-occurring alexithymia. It is important to understand what is specific to autism and what is due to other co-occurring characteristics to develop appropriate support for autistic people. However, most research on this topic has been conducted in adults, which limits our knowledge about the relevance of this theory to younger autistic populations. This study tested whether difficulties in emotion recognition and theory of mind traditionally associated with autism might be better explained by alexithymia in a sample of adolescents with and without a diagnosis of autism. Results found that difficulties in emotion recognition and theory of mind were both associated with autistic traits, and this was not accounted for by individual differences in levels of alexithymia. This research suggests that more work is needed to understand the applicability of the alexithymia hypothesis in younger populations, but that at least in adolescents and when using parent-report measures, alexithymia may not account for emotion recognition or theory of mind difficulties associated with autistic traits.

The Cerebellum as an Embodying Machine

Whereas emotion theorists often keep their distance from the embodied approach, theorists of embodiment tend to treat emotion as a mainly physiologic process. However, intimate links between emotions and the body suggest that emotions are privileged phenomena to attempt to reintegrate mind and body and that the body helps the mind in shaping emotional responses. To date, research has favored the cerebrum over other parts of the brain as a substrate of embodied emotions. However, given the widely demonstrated contribution of the cerebellum to emotional processing, research in affective neuroscience should consider embodiment theory as a useful approach for evaluating the cerebellar role in emotion and affect. The aim of this review is to insert the cerebellum among the structures needed to embody emotions, providing illustrative examples of cerebellar involvement in embodied emotions (as occurring in empathic abilities) and in impaired identification and expression of embodied emotions (as occurring in alexithymia).

Recognition of others' interoceptive states in those with and without eating disorders

BACKGROUND

The ability to recognize one's own emotions is associated with one's ability to recognize others' emotions. Beyond the domain of emotion, however, the relationship between recognition of one's own internal states (interoception) and others' interoceptive states has not been investigated, either in the typical population or clinical groups with interoceptive difficulties (e.g. eating disorders; EDs).

METHOD

This study investigated recognition of one's own and others' internal states in adults with and without eating disorders, using a high frequency visual noise paradigm. Participants completed self-report measures of interoception, alexithymia (difficulties recognising one's own emotional internal states) and ED symptomatology, and the Heartbeat Counting Task measure of cardiac interoceptive accuracy.

RESULTS

Alexithymia was significantly negatively correlated with recognition of others' interoceptive states. EDs were not associated with difficulties recognising others' interoceptive states.

CONCLUSIONS

The ability to recognise one's own emotional internal states is associated with the recognition of others' interoceptive states, which may contribute to social skills and the ability to care for others.

Revisiting alexithymia as an important construct in the treatment of anorexia nervosa: a proposal for future research

Consistent research supports altered emotional processing in adult patients with anorexia nervosa (AN), including elevations in alexithymia, or deficits in identifying and describing emotions and other internal experiences. Despite increasing interest in emotion-focused therapies for AN, alexithymia is often not directly addressed within many existing treatments, and little empirical work has moved beyond descriptive, cross-sectional research. In this paper, we propose that refining the field's understanding of alexithymia may provide insights into poor outcomes in existing psychological treatments for AN. First, we provide a brief overview of existing work exploring alexithymia in AN, and then describe several next steps in treatment-relevant research, including differentiating alexithymia from related constructs, considering neurobiological correlates of alexithymia, testing the link between alexithymia and outcome across treatment modalities, and piloting adjunctive treatment techniques focused on emotional identification and description. Altogether, exploring adjunctive treatment approaches targeting alexithymia may offer one promising possibility for improving long-term outcomes.

Parental-Bonding and Alexithymia in Adolescents with Anorexia Nervosa, Their Parents, and Siblings

Anorexia nervosa (AN) patients and their family-members share alexithymia, anxiety, depression, and other psychological symptoms, in the context of altered attachment. These domains have been individually studied in the context of eating disorders; few attempts have been made to study their interaction, especially including family members. In this study, alexithymia, parental-bonding, and psychopathology were assessed in 32 Italian families consisting of an adolescent AN patient, a sibling, and their parents. We aimed to (a) describe a sample of Italian families with a child affected by AN, notably including siblings; (b) investigate interactions between assessed constructs in patients and their siblings; and (c) investigate possible intergenerational effects. Results showed high alexithymia and psychopathological symptoms in patients but not in siblings, although the latter reported high obsession-compulsion and paranoid ideation scores. Patients' and siblings' alexithymia correlated with psychopathology. Parents reported generally low alexithymia. Perceived parental bonding was found to be suboptimal in most participants, yet no clear relationship was found between specific parenting styles and other measured traits, nor did we find any other relevant intergenerational effect. Anorexia nervosa implies psychological difficulties for all family members. Siblings' psychopathological traits are especially concerning and currently understudied. Implications for future research and clinical interventions are discussed.

Morphing analysis of facial emotion recognition in anorexia nervosa: association with physical activity

PURPOSE

Anorexia Nervosa (AN) has been linked to emotion processing inefficiencies, social cognition difficulties and emotion dysregulation, but data on Facial Emotion Recognition (FER) are heterogenous and inconclusive. This study aims to explore FER in patients with AN using a dynamic and ecological evaluation, and its relationship with Physical Activity (PA), an important aspect of AN that could impact emotional processing.

METHODS

Sixty-six participants (33 patients with AN and 33 healthy controls) performed a morphed facial emotional recognition task and 49 of them wore an accelerometer during seven days to assess PA. Axis-I disorders and depressive symptoms have been assessed.

RESULTS

No difference was found regarding time to recognize facial emotions. However, patients with AN correctly recognize emotions more frequently than controls. This was specific to disgust, although there was also a tendency for sadness. Among patients, higher depressive scores are associated with a faster and more accurate recognition of disgust, while a higher level of PA is associated to decreased accuracy in recognizing sadness.

CONCLUSION

Patients with AN are capable of recognizing facial emotions as accurately as controls, but could have a higher sensitivity in recognizing negative emotions, especially disgust and sadness. PA has opposite effects and, thus, could be considered as an emotional regulation strategy against negative affect.

LEVEL OF EVIDENCE II

Controlled trial without randomization.

The Value of Thinking About Feelings Across Cultures: A Preliminary Investigation of the Mentalizing Values Scale

In this proof-of-concept paper, we aimed to conduct a preliminary investigation of a newly developed scale that focuses on what we have termed “mentalizing values”—that is, the extent to which thinking about internal mental states is valued across different cultures. To this end, we report the results of a cross-cultural comparison of mentalizing values, Schwartz’s value dimensions, and two overlapping concepts: externally oriented thinking (EOT) and emotional awareness (EA), in a sample of students from Japan, the UK, and Israel ( N = 360). The results indicate that the mentalizing values scale (MVS) has good internal consistency in different languages and seems to capture a similar unidimensional construct across the three cultures. In Israel, people ranked mentalizing values as very important for them relative to other values, whereas in Japan, mentalizing values were relatively less important to people. In the UK, the relative importance of mentalizing values was between that assigned by their counterparts from Israel and Japan. EOT and EA were predicted by mentalizing values and by conservation across cultures, with mentalizing values explaining cultural differences over and above conservation, and mentalizing values being the only significant predictor within each culture. Finally, a parallel mediation model indicated that cultural differences in EOT and EA could be explained by mentalizing values and conservation. Overall, these findings lend initial support for the utility of the MVS and suggest that cultural variations in mentalizing values can be heavily intertwined with concepts that emphasize people’s tendency or capacity to think about feelings, such as EOT and EA.

Atypical interoception as a common risk factor for psychopathology: A review

The inadequacy of a categorial approach to mental health diagnosis is now well-recognised, with many authors, diagnostic manuals and funding bodies advocating a dimensional, trans-diagnostic approach to mental health research. Variance in interoception, the ability to perceive one's internal bodily state, is reported across diagnostic boundaries, and is associated with atypical functioning across symptom categories. Drawing on behavioural and neuroscientific evidence, we outline current research on the contribution of interoception to numerous cognitive and affective abilities (in both typical and clinical populations), and describe the interoceptive atypicalities seen in a range of psychiatric conditions. We discuss the role that interoception may play in the development and maintenance of psychopathology, as well as the ways in which interoception may differ across clinical presentations. A number of important areas for further research on the role of interoception in psychopathology are highlighted.

The moderating effects of self and other mentalizing on the relationship between distress and disordered eating: A cross-cultural examination

OBJECTIVE

Cross-cultural comparisons that focus on underlying psychological mechanisms in disordered eating (DE) are lacking. With the aim of addressing this gap, we investigated the interplay between mentalizing, distress, and DE in two cultural groups: the ultra-Orthodox and secular Jewish societies in Israel.

METHOD

A combination of performance-based and self-report measures of two mentalizing-related constructs (emotional awareness and alexithymia), along with self-report measures of distress, DE, and values preferences, were employed in a community sample (N = 300) of ultra-Orthodox and secular Jewish women.

RESULTS

Distress predicted DE in both cultural groups, yet there were cultural differences in the moderating role of mentalizing. Both mentalizing measures moderated the distress-DE link in the secular group, but not in the ultra-Orthodox group. Furthermore, there were cultural differences in the moderating effects of self versus other mentalizing.

CONCLUSIONS

The results suggest cultural differences in the underlying psychological mechanism of DE.

Siblings of Individuals With Eating Disorders: A Review of the Literature

Eating disorders (EDs) are serious psychopathologies characterized by a persistent disturbance in eating or eating-related behavior. Studies have shown EDs' detrimental consequences not only for patients, but also for their families. Nevertheless, a specific group that has so far been neglected, in both the research and clinical fields, are siblings of individuals with EDs. In an effort to identify this population's needs, and to facilitate effective prevention and treatment, this paper aims to review the existing literature on the subject, and examine siblings' personal experience, ways of coping, and levels of psychopathology. PubMed and PsycNet databases were searched with no publication date restrictions, yielding 26 relevant papers. Studies were categorized according to common themes they addressed, and subsequently summarized by highlighting common features, as well as information unique to each study. Several themes emerged, including emotional well-being, psychopathology, social consequences, family dynamics, and coping strategies. Results show that EDs experienced by one individual have significant effects on one's siblings, such as a decrease in quality of life, social isolation, and elevated familial strain. In several studies siblings were found to have elevated levels of psychopathology and EDs related symptoms. Nevertheless, findings' nature and magnitude were highly varied. The review indicates the need for further studies that will examine possible intra- and interpersonal moderating factors for EDs' impact on well-being among siblings, and take into consideration the substantial heterogeneity in studies conducted thus far. Additionally, this review highlights the need for novel and effective interventions, specifically targeting this at-risk group.

Parallel but independent reduction of emotional awareness and corpus callosum connectivity in older age

Differential functional specialization of the left and right hemispheres for linguistic and emotional functions, respectively, suggest that interhemispheric communication via the corpus callosum is critical for emotional awareness. Accordingly, it has been hypothesized that the age-related decline in callosal connectivity mediates the frequently demonstrated reduction in emotional awareness in older age. The present study tests this hypothesis in a sample of 307 healthy individuals between 20-89 years using combined structural and diffusion-tensor magnetic resonance imaging (MRI) of the corpus callosum. As assumed, inter-hemispheric connectivity (midsagittal callosal area and thickness, as well as fractional anisotropy, FA) and emotional awareness (i.e., increase in externally-oriented thinking, EOT; assessed with the Toronto Alexithymia Scale, TAS-20) were found to be reduced in older (> 60 years) compared to younger participants. Furthermore, relating callosal measures to emotional awareness, FA in the genu of the corpus callosum was found to be negatively correlated with EOT in male participants. Thus, "stronger" structural connectivity (higher FA) was related with higher emotional awareness (lower EOT). However, a formal mediation analysis did not support the notion that age-related decline in emotional awareness is mediated by the corpus callosum. Thus, the observed reduction of emotional awareness and callosal connectivity in older age likely reflects parallel but not inter-dependent processes.

Alexithymia explains increased empathic personal distress in individuals with and without eating disorders

It is often assumed that empathy impairments are common in individuals with eating disorders (EDs), but empirical work has been limited and produced mixed results, making the clinical features and treatment needs of this population difficult to determine. Alexithymia, characterised by difficulties identifying and describing one’s own emotions, frequently co-occurs with EDs and is associated with atypical recognition of, and empathy for, others’ emotions. This study used an existing empathy for pain paradigm to determine whether atypical empathy in EDs stems from co-occurring alexithymia, rather than EDs per se. Empathy (specifically personal distress in response to others’ pain) was assessed in individuals with EDs ( N = 21) and an alexithymia-matched control group ( N = 22). Participants were simultaneously members of a high alexithymia ( N = 16) or low alexithymia ( N = 27) group, allowing the independent contributions of alexithymia and EDs to be determined. Participants judged the laterality of hands and feet in painful and non-painful situations, and the degree of empathic interference on response times was measured. Results indicated that observation of painful stimuli affected task performance in those with high levels of alexithymia more than those with low levels, but no effect of ED diagnosis was observed. These findings suggest that co-occurring alexithymia explains increased empathic personal distress in ED populations. Atypical empathy may therefore not be a core feature of EDs, and interventions aimed at improving empathy-related social functioning may only be necessary for patients who also have alexithymia. These findings emphasise the importance of determining the influence of co-occurring alexithymia when assessing empathy in clinical populations.

Alexithymia: a general deficit of interoception

Alexithymia is a sub-clinical construct, traditionally characterized by difficulties identifying and describing one's own emotions. Despite the clear need for interoception (interpreting physical signals from the body) when identifying one's own emotions, little research has focused on the selectivity of this impairment. While it was originally assumed that the interoceptive deficit in alexithymia is specific to emotion, recent evidence suggests that alexithymia may also be associated with difficulties perceiving some non-affective interoceptive signals, such as one's heart rate. It is therefore possible that the impairment experienced by those with alexithymia is common to all aspects of interoception, such as interpreting signals of hunger, arousal, proprioception, tiredness and temperature. In order to determine whether alexithymia is associated with selectively impaired affective interoception, or general interoceptive impairment, we investigated the association between alexithymia and self-reported non-affective interoceptive ability, and the extent to which individuals perceive similarity between affective and non-affective states (both measured using questionnaires developed for the purpose of the current study), in both typical individuals (n = 105 (89 female), mean age = 27.5 years) and individuals reporting a diagnosis of a psychiatric condition (n = 103 (83 female), mean age = 31.3 years). Findings indicated that alexithymia was associated with poor non-affective interoception and increased perceived similarity between affective and non-affective states, in both the typical and clinical populations. We therefore suggest that rather than being specifically associated with affective impairment, alexithymia is better characterized by a general failure of interoception.

Intact social cognitive processes in outpatients with anorexia nervosa: a pilot study

OBJECTIVE

The aim of the study was to assess social cognition in community patients suffering from anorexia nervosa (AN) compared to healthy controls.

METHODS

25 women diagnosed with AN and 25 women matched for education level and age were involved in the study. Both subject groups were assessed using a set of validated experimental tasks, such as the facial expression recognition test, short recognition memory test for faces, 'Reading the mind in the eyes' test. Patients were assessed for symptoms of: eating disorder (the eating attitudes test-EAT-26), OCD (the Yale-Brown obsessive compulsive scale-Y-BOCS) and depression (Beck depression inventory-BDI). The research hypothesis indicated that patients suffering from anorexia represent no significant difference in social cognitive functioning in comparison to the healthy controls. These assessment scales were used to identify whether there are any problems according to social cognitive functioning especially emotion recognition and theory of mind (ToM). The primary outcome assessment was to identify social cognitive deficits in anorexic outpatients and secondary outcome was to verify whether these problems in emotional functioning found in women in acute phase of AN are state or trait effects.

RESULTS

Anorexic patients showed significantly higher scores on EAT-26, BDI and Y-BOCS. No significant differences were found in performance of social cognitive tests and facial perception test.

DISCUSSION

No marked alterations were found in social cognitive functioning in community patients with average body mass index (BMI) of 17.6. This may indicate that social cognition is a very complex construct to be reliably measured in anorexia nervosa considering relatively limited psychometric data for many social cognitive tasks. Further longitudinal studies are needed to untangle ongoing controversy whether social cognitive deficits in AN could be state or trait related.

Dimensions of emotion dysregulation in anorexia nervosa and bulimia nervosa: A conceptual review of the empirical literature

Several existing conceptual models and psychological interventions address or emphasize the role of emotion dysregulation in eating disorders. The current article uses Gratz and Roemer's (2004) multidimensional model of emotion regulation and dysregulation as a clinically relevant framework to review the extant literature on emotion dysregulation in anorexia nervosa (AN) and bulimia nervosa (BN). Specifically, the dimensions reviewed include: (1) the flexible use of adaptive and situationally appropriate strategies to modulate the duration and/or intensity of emotional responses, (2) the ability to successfully inhibit impulsive behavior and maintain goal-directed behavior in the context of emotional distress, (3) awareness, clarity, and acceptance of emotional states, and (4) the willingness to experience emotional distress in the pursuit of meaningful activities. The current review suggests that both AN and BN are characterized by broad emotion regulation deficits, with difficulties in emotion regulation across the four dimensions found to characterize both AN and BN, although a small number of more specific difficulties may distinguish the two disorders. The review concludes with a discussion of the clinical implications of the findings, as well as a summary of limitations of the existing empirical literature and suggestions for future research.

Alexithymia, a compounding factor for eating and social avoidance symptoms in anorexia nervosa

Socio-affective difficulties, in particular difficulties in representing, communicating and feeling emotions, may play a critical role in anorexia nervosa (AN). The aim of this longitudinal study was to explore the links between alexithymia and two types of difficulties in AN: eating symptoms and social avoidance. Sixty adolescent girls with AN were recruited following hospitalisation in a specialised department. They completed self-administered questionnaires of alexithymia (TAS-20), of central symptoms of the eating disorders (EDI), and of anxious and depressive affects (SCL-90). Anxiety and social avoidance were assessed in the course of a standardised interview (LSAS). These measures were performed at inclusion, and at 6-, 12- and 18-months' follow-up. The relationship between TAS-20 and EDI or LSAS total scale scores across the four time points was assessed using mixed-effects models, including anxiety, depression, BMI, anorexia subtype, and age as co-factors. Partial least square regression was used to refine this multivariate analysis at subscale level, at inclusion and 18 months. Robust associations between TAS-20 and EDI scores were found, independently from anxious and depressive scores, nutritional state and AN subtype. These effects appeared more particularly linked to the implication of the dimensions difficulties identifying and describing feelings, interpersonal mistrust, feelings of inadequacy and interoceptive awareness deficit. There was also a durable association between alexithymia and social anxiety and avoidance, after adjusting for the confounding effects of depression, and anxiety, and the state of starvation. Difficulties in describing feelings appeared particularly involved here. Thus alexithymia does appear as a factor in the persistence of disorders in AN, and difficulties identifying and describing feelings could compound the social difficulties and major the relational isolation of these patients.

Emotion recognition deficits in eating disorders are explained by co-occurring alexithymia

Previous research has yielded inconsistent findings regarding the ability of individuals with eating disorders (EDs) to recognize facial emotion, making the clinical features of this population hard to determine. This study tested the hypothesis that where observed, emotion recognition deficits exhibited by patients with EDs are due to alexithymia, a co-occurring condition also associated with emotion recognition difficulties. Ability to recognize facial emotion was investigated in a sample of individuals with EDs and varying degrees of co-occurring alexithymia, and an alexithymia-matched control group. Alexithymia, but not ED symptomology, was predictive of individuals' emotion recognition ability, inferred from tolerance to high-frequency visual noise. This relationship was specific to emotion recognition, as neither alexithymia nor ED symptomology was associated with ability to recognize facial identity. These findings suggest that emotion recognition difficulties exhibited by patients with ED are attributable to alexithymia, and may not be a feature of EDs per se.

Empathy and social functioning in anorexia nervosa before and after recovery

INTRODUCTION

People with anorexia nervosa (AN) are known to have difficulties with social and emotional functioning, as indicated by their symptom presentation and also performance on tests of emotion perception. This study explores the level of empathy in AN, in terms of resonant experience of emotion in other people using a self-report measure.

METHODS

Twenty-eight women with acute AN were compared to 25 women who have recovered from AN, and a further 54 healthy control (HC) participants. They were assessed using a questionnaire to measure reported levels of empathy, emotional recognition, social conformity, and antisocial behaviour.

RESULTS

The acute AN group reported lower levels of empathy than the recovered AN group and HC, but they also reported less antisocial behaviour. No differences were found in emotional recognition or social conformity.

CONCLUSIONS

These results suggest that emotional empathy is reduced during acute AN. Lower levels of antisocial behaviour may reflect a contrasting desire of people with AN to minimise presentation of antisocial behaviour in the acute state.

Toronto alexithymia scale for patients with eating disorder: [corrected] performance using the non-parametric item response theory

BACKGROUND

The aim of this study was to investigate the performance of the Toronto Alexithymia Scale (TAS-20) in patients with eating disorders. As a secondary objective, we analyzed a subset of items in order to determine whether the total score is a good tool for classifying these patients and whether the items are ordered according to the difficulty of choosing a particular answer depending on the severity of the patient's condition.

SUBJECTS AND METHODS

We administered the TAS-20 to 103 consecutive patients who met DSM-IV-R criteria for anorexia nervosa, bulimia nervosa, or eating disorders not otherwise specified. Mokken scale analysis, nonparametric item response theory (NIRT), and confirmatory factor analysis (CFA) were used to test the psychometric properties of the scale. To improve our understanding of the structure underlying the TAS-20, we used an automated item selection procedure based on the Mokken scale.

RESULTS

We identified a subset of 13 independent and clinically interpretable items that are potentially sufficient to rate patients with alexithymia. This subset was considered a unidimensional reduction of the TAS-20. However, the scale composed of this subset needs to be validated. Thirteen of the 20 items were maximally related to alexithymia because they have a one-dimensional structure. The NIRT and CFA enabled us to identify a maximal subset of items that conform to the requirements for good measurement of alexithymia in patients with eating disorders.

Anorexia nervosa and its relation to depression, anxiety, alexithymia and emotional processing deficits

PURPOSE

Psychopathological changes and dysfunction in emotion processing have been described for anorexia nervosa (AN). Yet, findings are applicable to adult patients only. Furthermore, potential for discriminative power in clinical practice in relation to clinical parameters has to be discussed. The aim of this study was to investigate psychopathology and emotional face processing in adolescent female patients with AN.

METHODS

In a sample of 15 adolescent female patients with AN (16.2 years, SD ± 1.26) and 15 age and sex matched controls we assessed alexithymia, depression, anxiety and empathy in addition to emotion labelling and social information processing.

RESULTS

AN patients had significantly higher alexithymia, higher levels of depression, and state and trait anxiety compared to controls. There was a trend for a lower ability to recognize disgust. Happiness as a positive emotion was recognized better. All facial expressions were recognized significantly faster by AN patients. Associations of pathological eating behaviour and trait anxiety were seen.

CONCLUSION

In accordance with the stress reduction hypothesis, typical psychopathology of alexithymia, anxiety and depression is prevalent in female adolescent AN patients. It is present detached from physical stability. Pathogenesis of AN is multifactorial and already fully present in adolescence. An additional reinforcement process can be discussed. For clinical practice, those parameters might have a better potential for early prognostic factors related to AN than physical parameters and possible implication for intervention is given.

A systematic review and meta-analysis of 'Systems for Social Processes' in eating disorders

Social and emotional problems have been implicated in the development and maintenance of eating disorders (ED). This paper reviews the facets of social processing in ED according to the NIMH Research and Domain Criteria (NIMH RDoC) 'Systems for Social Processes' framework. Embase, Medline, PsycInfo and Web of Science were searched for peer-reviewed articles published by March 2013. One-hundred and fifty four studies measuring constructs of: attachment, social communication, perception and understanding of self and others, and social dominance in people with ED, were identified. Eleven meta-analyses were performed, they showed evidence that people with ED had attachment insecurity (d=1.31), perceived low parental care (d=.51), appraised high parental overprotection (d=0.29), impaired facial emotion recognition (d=.44) and facial communication (d=2.10), increased facial avoidance (d=.52), reduced agency (d=.39), negative self-evaluation (d=2.27), alexithymia (d=.66), poor understanding of mental states (d=1.07) and sensitivity to social dominance (d=1.08). There is less evidence for problems with production and reception of non-facial communication, animacy and action.

Intra and inter hemispheric dynamics revealed by reaction time in the Dimond paradigm: a quantitative review of the literature

In stimulus matching tasks requiring discrimination of two unilaterally or bilaterally presented stimuli (Dimond paradigm), a well established intrahemispheric processing bottleneck model predicts that an increase in task difficulty as measured by reaction time should provide an advantage to bilateral stimulations. The purpose of the current investigation was to review the entire relevant literature on the Dimond paradigm and identify the experimental variables which reliably yield such effects. Forty nine experimental effects compatible with the "intrahemispheric processing bottleneck" model and 26 contrary effects were found. Manipulation of the complexity of the stimulus matching criterion significantly produced intrahemispheric bottleneck effects. This effect was also significantly greater when non-target stimuli required heavier processing. These two findings support the intrahemispheric bottleneck model: computationally complex tasks seem to overload a hemisphere׳s processing capacity, an effect seen in the unilateral presentation conditions. However, manipulating the similarity of target stimuli produced contrary effects. Contrary effects were also obtained more readily when two physical matching tasks were compared. These two latter effects may best be explained as low level visual-perceptual limitations of interhemispheric transfer or integration.

Alexithymia in parents and adolescent anorexic daughters: comparing the responses to TSIA and TAS-20 scales

BACKGROUND

A growing body of literature has been focusing on individual alexithymia in anorexia nervosa, while there are only scarce and conflicting studies on alexithymia in the families of anorexic patients, despite the important role played by family dynamics in the development of the anorexic disorder, especially in adolescent patients. The aim of this study is to assess alexithymia in anorexic adolescent patients and in their parents using a multimethod measurement to gain more direct, in-depth knowledge of the problem.

METHODS

Forty-six subjects, anorexic adolescent patients and their parents, underwent the Toronto Alexithymia Scale (TAS-20) along with the Toronto Structured Interview for Alexithymia (TSIA), which represents the first comprehensive clinically structured interview focused specifically on assessing alexithymia. The use of latent trait Rasch analysis allowed a comparison of the two instruments' sensitivity and ability to detect the presence and intensity of alexithymic components in patients and parents.

RESULTS

Significant discordance was found between the two measures. The clinical instrument allowed detection of a greater level of alexithymia compared with the self-report, in particular in our adult parent sample. Moreover, a significant alexithymic gap emerged within families, particularly within parental couples, with noticeably more alexithymic fathers compared with the mothers.

CONCLUSION

The TSIA clinical interview may be a more sensitive instrument in detecting alexithymia, minimizing parents' negation tendency. Clinical questions have arisen on how useful it would be to give greater weight to family functioning (ie, alexithymic gap) in order to predict the possibility of establishing a therapeutic alliance, and thus the outcome of the anorexic adolescent.

Advances in the neurobiology of eating disorders

PURPOSE OF REVIEW

To systematize new neurobiological findings on the cause and treatment of eating disorders.

RECENT FINDINGS

The conceptual framework of the cause of eating disorders has undergone great changes in the past decades. Recently, the National Institute of Mental Health proposed a new set of criteria for research purposes--the Research Domain Criteria (RDoC). We aim to structure this study as much as possible using these constructs across biological units of analysis, summarizing new findings. Brain imaging techniques have become sophisticated in identifying brain circuits related to illness behaviour and to fundamental traits such as reward and social processing. Genetic studies have moved from candidate gene studies onto genome-wide association studies; however, the field needs to cooperate to collect larger samples in order to benefit from this approach. Hormonal changes as the results of starvation or as underlying factors for behavioural changes still receive attention in both animal and human studies. Advances made in neuropsychology show problems in cognition (set shifting and central coherence) and in other RDoC domains. Some of these findings have been translated into treatment.

SUMMARY

New biological models are being developed which explain causal and maintaining factors. The RDoC construct may be used to systematize these findings.

Levels of autistic traits in anorexia nervosa: a comparative psychometric study

BACKGROUND

A number of characteristics associated with Autism Spectrum Disorders (ASD) are over-represented among patients with Anorexia Nervosa (AN) as well as among relatives of these patients. Yet the co-occurrence of autistic traits in AN has not been fully explored and no previous study has directly compared self-reported evaluations of cognitive and socio-affective skills in AN and ASD.

METHODS

We aimed to determine the degree of overlap between AN and ASD from scores on questionnaires classically used to measure ASD impairments. Fifteen AN participants, 15 ASD participants and two groups of matched controls completed a battery of self-reports measuring: autistic traits (Autism-Spectrum Quotient), empathy (Empathy Quotient-short and Interpersonal Reactivity Index), systemizing (Systemizing Quotient-short) and alexithymia (Bermond-Vorst Alexithymia Questionnaire-B). Univariate comparisons of mean totalled scores were performed on each measure (patients vs. controls, and AN vs. ASD), and a Principal Component Analysis was used to study subject proximities in a reduced-factor space constructed from AQ, BVAQ-B and IRI subscales.

RESULTS

These analyses revealed similarities in a few cognitive domains (Attention Switching, Perspective Taking and Fantasy, lack of emotional introspection) and in some nonspecific affective dimensions (depression and feelings of distress), but also marked dissimilarities in social skills (the ability to communicate emotions to others, empathizing).

CONCLUSION

The AN and ASD participants reported similar needs for sameness, and similar difficulties understanding their emotions and taking the perspective of another, but contrasting abilities to feel concerned in interpersonal situations. Our mixed findings encourage further exploration of transdiagnostic similarities and associations between these disorders.

The cognitive-interpersonal maintenance model of anorexia nervosa revisited: a summary of the evidence for cognitive, socio-emotional and interpersonal predisposing and perpetuating factors

AIM

To describe the evidence base relating to the Cognitive-Interpersonal Maintenance Model for anorexia nervosa (AN).

BACKGROUND

A Cognitive-Interpersonal Maintenance Model maintenance model for anorexia nervosa was described in 2006. This model proposed that cognitive, socio-emotional and interpersonal elements acted together to both cause and maintain eating disorders.

METHOD

A review of the empirical literature relating to the key constructs of the model (cognitive, socio-emotional, interpersonal) risk and maintaining factors for anorexia nervosa was conducted.

RESULTS

Set shifting and weak central coherence (associated with obsessive compulsive traits) have been widely studied. There is some evidence to suggest that a strong eye for detail and weak set shifting are inherited vulnerabilities to AN. Set shifting and global integration are impaired in the ill state and contribute to weak central coherence. In addition, there are wide-ranging impairments in socio-emotional processing including: an automatic bias in attention towards critical and domineering faces and away from compassionate faces; impaired signalling of, interpretation and regulation of emotions. Difficulties in social cognition may in part be a consequence of starvation but inherited vulnerabilities may also contribute to these traits. The shared familial traits may accentuate family members' tendency to react to the frustrating and frightening symptoms of AN with high expressed emotion (criticism, hostility, overprotection), and inadvertently perpetuate the problem.

CONCLUSION

The cognitive interpersonal model is supported by accumulating evidence. The model is complex in that cognitive and socio-emotional factors both predispose to the illness and are exaggerated in the ill state. Furthermore, some of the traits are inherited vulnerabilities and are present in family members. The clinical formulations from the model are described as are new possibilities for targeted treatment.

Inpatients with severe anorexia nervosa and their siblings: non-shared experiences and family functioning

OBJECTIVES

The aims of this study were the following: to identify perceptions of patients with anorexia nervosa (AN) and their siblings regarding differential experiences within and external to the family including sibling interactions, parental treatment, relationships with peers and events that are unique to each sibling; (2) to compare how patients and their siblings perceive eating disorder symptoms, parental affection/control, social support and stigma; and (3) to test associations with family functioning for patients with AN and their siblings.

METHOD

A total of 26 patients paired with their siblings were recruited from an Eating Disorder Program and administered standardized instruments measuring different experiences within and external to the family, the impact of eating disorder behaviours, stigma, social support and family functioning.

RESULTS

Patients rated high on the differential experience of jealousy in contrast to their siblings. Patients scored higher than their siblings on eating symptoms, whereas siblings scored higher on social support. The impact of AN on the family, stigma towards the individual and family, and social support accounted for 37% of the variance in family functioning from the sibling perspective after controlling for age and gender. Of these variables, impact of AN on the family made the largest contribution.

DISCUSSION

Family-based and sibling-based interventions that aim to reduce the effects of the illness on the sibling relationship and the family are recommended.

Alexithymia and eating disorders: a critical review of the literature

Alexithymia is characterized by difficulties identifying feelings and differentiating between feelings and bodily sensations, difficulties communicating feelings, and a concrete cognitive style focused on the external environment. Individuals with eating disorders have elevated levels of alexithymia, particularly difficulties identifying and describing their feelings. A number of theoretical models have suggested that individuals with eating disorders may find emotions unacceptable and/or frightening and may use their eating disorder symptoms (i.e., restricting food intake, bingeing, and/or purging) as a way to avoid or cope with their feelings. The current critical review synthesizes the literature on alexithymia and eating disorders and examines alexithymia levels across eating disorders (i.e., anorexia nervosa, bulimia nervosa, and eating disorder not otherwise specified), the role of alexithymia in binge eating disorder, and the influence of alexithymia on the development of eating disorders as well as treatment outcome. The clinical implications of the research conducted to date and directions for future research are discussed.

Social cognition in anorexia nervosa: evidence of preserved theory of mind and impaired emotional functioning

BACKGROUND

The findings of the few studies that have to date investigated the way in which individuals with Anorexia Nervosa (AN) navigate their social environment are somewhat contradictory. We undertook this study to shed new light on the social-cognitive profile of patients with AN, analysing Theory of Mind and emotional functioning. Starting from previous evidence on the role of the amygdala in the neurobiology of AN and in the social cognition, we hypothesise preserved Theory of Mind and impaired emotional functioning in patients with AN.

METHODOLOGY

Thirty women diagnosed with AN and thirty-two women matched for education and age were involved in the study. Theory of Mind and emotional functioning were assessed with a set of validated experimental tasks. A measure of perceived social support was also used to test the correlations between this dimension and the social-cognitive profile of AN patients.

PRINCIPAL FINDINGS

The performance of patients with AN is significantly worse than that of healthy controls on tasks assessing emotional functioning, whereas patients' performance is comparable to that of healthy controls on the Theory of Mind task. Correlation analyses showed no relationship between scores on any of the social-cognition tasks and either age of onset or duration of illness. A correlation between social support and emotional functioning was found. This latter result seems to suggest a potential role of social support in the treatment and recovery of AN.

CONCLUSIONS

The pattern of results followed the experimental hypothesis. They may be useful to help us better understand the social-cognitive profile of patients with AN and to contribute to the development of effective interventions based on the ways in which patients with AN actually perceive their social environment.