Attribution of mental States to others by schizophrenic patients

A Systematic Review of the Current Measures of Theory of Mind in Adults with Schizophrenia

Adults with schizophrenia usually have impairments in theory of mind (ToM), which subsequently cause them problems in social interaction. Therefore, it is important for healthcare providers to assess their ToM using adequate measures. This systematic review evaluated current ToM measures (or ToM tasks) for adults with schizophrenia and summarized their specific characteristics, including the concept and construct, administration, and psychometric properties. From a review of 117 articles, 13 types of ToM tasks were identified, and the findings from these articles were qualitatively synthesized. The results showed that ToM tasks are diverse in their presentation modalities, answer modes, strategies of controlling cognitive confounders, and scoring. Most tasks employ cognitive and affective dimensions and target a specific, single ToM concept. The present systematic review found that psychometric evidence supporting the ToM tasks, such as internal consistency, test–retest reliability, unidimensionality, and convergent, criterion, and ecological validities, is insufficient. Based on the results, we propose several principles for selecting appropriate ToM tasks in practice, e.g., selecting a task with multiple ToM concepts, or an exclusive ToM construct containing the cognitive and affective dimensions. Moreover, future studies are needed to provide more psychometric evidence on each type of ToM task applied in people with schizophrenia.

The intentionality bias in schizotypy: a social matter

INTRODUCTION

We aimed to investigate the association between schizotypy and intentionality bias, the tendency to interpret ambiguous actions as being intentional, for social and non-social actions separately. This bias contributes to interpersonal difficulties, and has been associated with psychotic symptoms, such as delusions. However, results have been inconsistent for an association between putative psychosis proneness, schizotypy, and intentionality bias. Further, the multidimensional nature of schizotypy has not been considered. Agreeableness was measured to examine the specificity of the relationship, and inhibition to examine its potential role as a mediator.

METHODS

Two online studies are reported (n = 280 and n = 163) in which participants made intentionality judgements about ambiguous actions described in sentences. They also completed questionnaire measures of schizotypy and agreeableness, and inhibitory efficiency (a sentence completion task).

RESULTS

Schizotypy was associated with perceiving ambiguous actions as intentional, particularly in social contexts, after controlling for agreeableness. The association with social intentionality was stronger for schizotypy subscales capturing paranoia and unusual beliefs. Inhibitory efficiency as not a significant predictor of intentionality bias.

CONCLUSION

These finding suggest intentionality biases for social and non-social events are distinguishable. In relation to schizotypy, social situations appear to generate perceptions of intentionality. Intentionality bias represents a phenotypic cognitive risk for psychosis which should be further investigated.

Rating scale for the assessment of communication disorders in schizophrenics

Taking up the Bleulerian view of a clinical description based on a pathogenic model, we propose a rating scale for the assessment of communication disorders in schizophrenic patients. The scale consists of clinical items that could be the direct expression of the three hypotheses of cognitive dysfunction which have been postulated to explain communication dysfunction in these patients. We assessed the frequency of the 16 items in the scale in a total of 80 subjects (43 schizophrenic subjects, ten manic subjects, 17 depressive subjects and ten normal control subjects). The results of this study showed that this item schedule was specific to schizophrenic patients and, in particular, could statistically significantly discriminate schizophrenic patients from psychotic patients with affective disorder. The methodological qualities of the scale were explored and proved accurate, except for the reliability which is too low for some items and the item-to-total correlation which is too low for one item of the scale.

What Do You Have in Mind? Measures to Assess Mental State Reasoning in Neuropsychiatric Populations

Social interaction is closely associated with both functional capacity and well-being. Previous research has not only revealed evidence of social dysfunction in individuals with a wide range of psychiatric and neurological disorders but also generated an abundance of potential measures for assessing social cognition. This review explores the most popular measures used within neuropsychiatric populations to investigate the ability to recognize or reason about the mental states of others. Measures are also critically analyzed in terms of strengths and limitations to aid task selection in future clinical studies. The most frequently applied assessment tools use verbal, visual or audiovisual forms of presentation and assess recognition of mental states from facial features, self-rated empathy, the understanding of other's cognitive mental states such as beliefs and intentions, or the ability to combine knowledge of other's thoughts and emotions in order to understand subtle communications or socially inappropriate behavior. Key weaknesses of previous research include limited investigation of relationships with clinical symptoms, and underutilization of measures of everyday social functioning that offer a useful counterpart to traditional "lab" tasks. Future studies should aim to carefully select measures not only based on the range of skills to be assessed but also taking into account potential difficulties with interpretation and the need to gain insight into the application of social cognitive skills as well as ability per se. Some of the best measures include those with well-matched control trials (e.g., Yoni Task) or those that restrict the influence of verbal deficits (e.g., intentions comic strip task), elicit spontaneous mentalizing (e.g., Animations Task), and possess greater ecological validity (e.g., Movie for the Assessment of Social Cognition). Social cognitive research within psychiatric populations will be further enhanced through the development of more closely matched control tasks, and the exploration of relationships between task performance, medication, strategy use, and broader emotional and motor functions.

From "under" to "over" social cognition in schizophrenia: Is there distinct profiles of impairments according to negative and positive symptoms?

Interactions between social cognition and symptoms of schizophrenia have been investigated, but mostly component by component. Here we tested the assumption that two categories of deficits exist depending on clinical profiles, one corresponding to a defect in social cognition – “under-social cognition” – and one corresponding to excessive attributions leading to social cognitive impairments – “over-social cognition”. To conduct the investigation, we performed a Hierarchical Clustering Analysis using positive and negative symptoms in seventy patients with schizophrenia and we compared the clusters obtained to a group of healthy controls on social cognitive measures. We distinguished two social cognitive profiles based on prevailing symptoms for emotion processes and Theory of Mind. Actually, patients with negative symptoms showed lower performances in emotion recognition task than both those with positive symptoms and controls. Concerning Theory of Mind, patients with positive symptoms had a significant tendency to make over interpretative errors than both patients with negative symptoms and controls. For other processes assessed, further explorations are needed. Actually, concerning social perception and knowledge both patients' groups presented significant impairments compared to controls. Assessment of attribution bias showed that patients in the positive group presented a significant hostility bias and a higher intentionality score compared to healthy controls. These results favor the existence of different categories of impairments depending more on the clinical characteristics of patients than on nosographical categories, but further investigations are now necessary to specify these profiles. It nevertheless showed the importance of assessing symptoms in relationship with cognitive functioning.

Patients with schizophrenia are less prone to interpret virtual others' empathetic questioning as helpful

Individuals with schizophrenia are impaired in their neurocognition and present cognitive biases. These impairments may lead to a deficit in recognizing helping intentions of others. To investigate recognition of help, we designed a card-guessing game (Virtual Help Recognition Paradigm) involving two successive virtual agents asking questions to the participant at different moments of the game. These questions were either empathetic (i.e. on the subject's feelings) or non-empathetic (i.e. on technical aspects of the game). We assessed how much the participant felt that the virtual agent had helped him and, her attitude and personality traits. We measured how much the participant trusted the virtual agent with a monetary allocation procedure. Twenty individuals with schizophrenia and twenty healthy controls were recruited. The controls' ratings demonstrated that they interpreted empathetic questioning as helping and rewarded it positively with an increased monetary allocation. Participants with schizophrenia had a reduced perception of the differences between the two agents. Only the rating concerning the "interest/attention" of the agent toward these participants yielded significant differences among conditions. Hypothetically, individuals with schizophrenia take into account the fact they are the object of another's attention, but may fail to infer a helping intention and to behave accordingly.

Schizotypy, autobiographical memory, and theory of mind: sex differences

Individuals with schizophrenia exhibit a range of cognitive impairments, including tasks assessing theory of mind (ToM) and autobiographical memory (AM). This study appears to be the first to examine how ToM and AM abilities interact in relation to schizotypy. Forty-seven undergraduate students reporting a wide continuous range of scores on the Schizotypal Personality Questionnaire (SPQ) completed a measure of ToM and a measure assessing various phenomenological qualities of AM. Female participants exhibited a negative correlation between the ToM score and the SPQ total score and a positive correlation between enhanced phenomenological qualities of AM and the SPQ disorganized factor score. No statistically significant relationships were found for male participants. ToM was negatively correlated with AM across the entire sample, which was not moderated by sex or schizotypy. It is possible that distinct underlying mechanisms account for the observed sex differences on ToM and AM performance in schizophrenia-related conditions.

The intentionality bias in schizophrenia

The tendency to over-interpret events of daily life as resulting from voluntary or intentional actions is one of the key aspects of schizophrenia with persecutory delusions. Here, we ask whether this characteristic may emerge from the abnormal activity of a basic cognitive process found in healthy adults and children: the intentionality bias, which refers to the implicit and automatic inclination to interpret human actions as intentional (Rosset, 2008, Cognition 108, 771-780). In our experiment, patients with schizophrenia and healthy controls were shown sentences describing human actions in various linguistic contexts, and were asked to indicate whether the action was intentional or not. The results indicated that people with schizophrenia exhibited a striking bias to over attribute intentionality regardless of linguistic context, contrary to healthy controls who did not exhibit such a general intentionality bias. Moreover, this study provides some insight into the cognitive mechanisms underlying this bias: an inability to inhibit the automatic attribution of intentionality.

From adversity to psychosis: pathways and mechanisms from specific adversities to specific symptoms

PURPOSE

Although there is considerable evidence that adversities in childhood such as social deprivation, sexual abuse, separation from parents, neglect and exposure to deviant parental communication are associated with psychosis in later life, most studies have considered broad diagnoses as outcomes. In this review we consider evidence for pathways between specific types of adversity and specific symptoms of psychosis.

METHODS

We present theoretical arguments for expecting some degree of specificity (although by no means perfect specificity) between different kinds of adversity and different symptoms of psychosis. We review studies that have investigated social-environmental risk factors for thought disorder, auditory-verbal hallucinations and paranoid delusions, and consider how these risk factors may impact on specific psychological and biological mechanisms.

RESULTS

Communication deviance in parents has been implicated in the development of thought disorder in offspring, childhood sexual abuse has been particularly implicated in auditory-verbal hallucinations, and attachment-disrupting events (e.g. neglect, being brought up in an institution) may have particular potency for the development of paranoid symptoms. Current research on psychological mechanisms underlying these symptoms suggests a number of symptom-specific mechanisms that may explain these associations.

CONCLUSIONS

Few studies have considered symptoms, underlying mechanisms and different kinds of adversity at the same time. Future research along these lines will have the potential to elucidate the mechanisms that lead to severe mental illness, and may have considerable clinical implications.

Theory of mind in schizophrenia: correlation with clinical symptomatology, emotional recognition and ward behavior

INTRODUCTION

Several studies have suggested the presence of a theory of mind (ToM) deficit in schizophrenic disorders. This study examined the relationship of emotion recognition, theory of mind, and ward behavior in patients with schizophrenia.

METHODS

Fifty-five patients with chronic schizophrenia completed measures of emotion recognition, ToM, intelligence, Positive and Negative Syndrome Scale (PANSS) and Nurse's Observation Scale for Inpatient Evaluation (NOSIE).

RESULTS

Theory of mind sum score correlated significantly with IQ, emotion recognition, and ward behavior. Ward behavior was linked to the duration of the illness, and even more so to theory of mind deficits. Theory of mind contributed a significant proportion of the amount of variance to explain social behavior on the ward.

DISCUSSION

Considering our study results, impaired theory of mind contributes significantly to the understanding of social competence in patients with schizophrenia.

Investigating the genetic basis of theory of mind (ToM): the role of catechol-O-methyltransferase (COMT) gene polymorphisms

The ability to deduce other persons' mental states and emotions which has been termed ‘theory of mind (ToM)’ is highly heritable. First molecular genetic studies focused on some dopamine-related genes, while the genetic basis underlying different components of ToM (affective ToM and cognitive ToM) remain unknown. The current study tested 7 candidate polymorphisms (rs4680, rs4633, rs2020917, rs2239393, rs737865, rs174699 and rs59938883) on the catechol-O-methyltransferase (COMT) gene. We investigated how these polymorphisms relate to different components of ToM. 101 adults participated in our study; all were genetically unrelated, non-clinical and healthy Chinese subjects. Different ToM tasks were applied to detect their theory of mind ability. The results showed that the COMT gene rs2020917 and rs737865 SNPs were associated with cognitive ToM performance, while the COMT gene rs5993883 SNP was related to affective ToM, in which a significant gender-genotype interaction was found (p = 0.039). Our results highlighted the contribution of DA-related COMT gene on ToM performance. Moreover, we found out that the different SNP at the same gene relates to the discriminative aspect of ToM. Our research provides some preliminary evidence to the genetic basis of theory of mind which still awaits further studies.

[Theory of mind and schizophrenia]

In social cognition, the notion of Theory of Mind (ToM) is widely studied among people with schizophrenia to give an account for intersubjective disturbances. ToM is classically defined as the ability to make inferences about other persons'mental states, as beliefs, thoughts or intentions. However, ToM is not understood or explored as a homogeneous notion. First, this review briefly describes main theoretical models, as well as experimental tasks of ToM. Second, clinical results strongly suggest that patients with schizophrenia present impaired ToM performances. However, the presence of a robust relationship between ToM and schizophrenic symptomatology, or clinical course, is still controversial. Third, we highlight main findings from functional brain imaging studies based on ToM. Finally and in a more critical perspective, we suggest a few theoretical and experimental limitations regarding impaired ToM as a core feature of schizophrenic disturbances in social interactions.

Cognitive impairment in schizophrenia

Cognitive functioning is moderately to severely impaired in patients with schizophrenia. This impairment is the prime driver of the significant disabilities in occupational, social, and economic functioning in patients with schizophrenia and an important treatment target. The profile of deficits in schizophrenia includes many of the most important aspects of human cognition: attention, memory, reasoning, and processing speed. While various efforts are under way to identify specific aspects of neurocognition that may lie closest to the neurobiological etiology and pathophysiology of the illness, and may provide relevant convergence with animal models of cognition, standard neuropsychological measures continue to demonstrate the greatest sensitivity to functionally relevant cognitive impairment.The effects of antipsychotic medications on cognition in schizophrenia and first-episode psychosis appear to be minimal. Important work on the effects of add-on pharmacologic treatments is ongoing. Very few of the studies completed to date have had sufficient statistical power to generate firm conclusions; recent studies examining novel add-on treatments have produced some encouraging findings. Cognitive remediation programs have generated considerable interest as these methods are far less costly than pharmacologic treatment and are likely to be safer. A growing consensus suggests that these interventions produce modest gains for patients with schizophrenia, but the efficacy of the various methods used has not been empirically investigated.

Theory of mind and paranoia in schizophrenia: a game theoretical investigation framework

INTRODUCTION. Ample evidence already shows that theory of mind (ToM) is impaired in people with schizophrenia. Our aim was to critically review this literature. METHOD. We completed a selected review of the research literature on ToM in schizophrenia. RESULTS. Gaps in ToM research were identified. A specific relationship between impaired ToM and paranoid delusions, although intuitively reasonable from a theoretical basis, has only been demonstrated in a few studies. Psychometric properties of ToM tasks employed in these studies may be a confounding factor in drawing conclusions about the relationship. Because most ToM measures have focused on the third-person perspective, participants are not actively interacting. The tasks fail to capture the cognitive demands faced by individuals in real-life situations, and, in effect, are not a direct measure of ToM. CONCLUSIONS. Potential research areas are discussed. Since game theoretical paradigms require the direct involvement of the first person and situate the participant's interpersonal reasoning within an interactive context, they provide more ecologically valid experimental platforms than conventional questionnaire measures to assess ToM in schizophrenia research.

Theory of Mind and psychometric schizotypy

The extent to which Theory of Mind impairments are a trait associated with schizotypy is unclear. To date, findings have been mixed. We compared two groups of psychometrically identified schizotypes, namely, those characterized by positive schizotypy (perceptual aberrations and magical ideation; n=36) and those characterized by negative schizotypy (social anhedonia; n=30) to a low schizotypy comparison group (n=68) in terms of their Theory of Mind performance. Theory of Mind was assessed in two ways: a composite Hinting Task and the Reading the Mind in the Eyes Test. The groups were also compared in terms of their self-reported levels of referential thinking. Our results indicate that individuals characterized by positive schizotypy show Theory of Mind deficits, as measured by the Hinting Task. The three groups did not differ in terms of the Eyes Test. Referential thinking was significantly associated with the Eyes Test but not the Hinting Task. Overall these findings suggest that different aspects of schizotypy are associated differentially with Theory of Mind deficits. The results also provide further rationale for the inclusion of multiple tasks when attempting to study multifaceted constructs such as Theory of Mind.

Mental state attribution in schizophrenia: what distinguishes patients with "poor" from patients with "fair" mentalising skills?

PURPOSE

Although many patients with schizophrenia are impaired in mental states attribution abilities, a significant number perform within normal or near-normal ranges in mental state attribution tasks. No studies have analysed cognitive or behavioural differences between patients with - to some extent - preserved mental state attribution skills and those with poor mentalising abilities.

MATERIAL AND METHODS

To examine characteristics of "poor" and "fair" mentalisers, 58 patients with schizophrenia performed a mental state attribution task, a test of general intelligence, and two executive functioning tests. "Poor" and "fair" mentalising skills were defined according to a median-split procedure; the median score in the patient group was also within two standard deviations of the control group. In addition, patients' social behavioural skills and psychopathological profiles were rated.

RESULTS

Patients performing within normal or near normal ranges on the mental state attribution task had fewer social behavioural abnormalities than patients with poor mentalising abilities (even when controlled for intelligence), but did not differ in executive functioning. Fair mental state performers showed less disorganisation and excitement symptoms than poor performers. The degree of disorganisation mediated the influence of mental state attribution on social behavioural skills.

CONCLUSIONS

Schizophrenia patients with (partially) preserved mentalising skills have fewer behavioural problems in the social domain than patients with poor mentalising abilities. Conceptual disorganisation mediates the prediction of social behavioural skills through mentalising skills, suggesting that disorganised patients may require special attention regarding social-cognitive skills training.

What is it like to be a person with schizophrenia in the social world? A first-person perspective study on Schizophrenic dissociality--part 1: state of the art

This is a critical review of research on the subjective experience of social dysfunction in persons with schizophrenia. Studies from the phenomenological and cognitive paradigms are examined, and significant outcomes and shortcomings are pointed out. Clinical phenomenologists have mainly interpreted schizophrenic dissociality as an anomaly of prereflexive attunement. The main shortcoming of phenomenological research is that it lacks adequate methodology to collect reliable data since most studies are based on the analysis of a few typical cases. Cognitivism has reliably documented disorders of social functioning in large-scale experimental studies. The main shortcoming of most cognitive paradigms is that they do not properly investigate the personal level of experience in real-world functioning. We conclude that there is a need to reliably collect data through quantitative as well as qualitative methodology as established and accepted by the scientific community in the area of schizophrenic dissociality, reflecting the subjective experiences of people with schizophrenia in the real world.

Clinically Relevant Measures of Children's Theory of Mind and Knowledge about Thinking: Non-Standard and Advanced Measures

Measures of Theory of Mind (ToM) in clinical disorders and conditions are reviewed, focusing on non-standard and advanced measures. Relevant studies linking these measures to social problems and cognitive symptoms are reviewed. The multifaceted nature of ToM is stressed and clinically relevant aspects of ToM are suggested. Strategies to select relevant measures for clinical research and practice are presented and examples are discussed in more detail. It is recommended to consider specific aspects of ToM in relation to specific clinical conditions and symptoms. Relationships between ToM and other cognitive deficits, and implications for clinical practice and intervention are also discussed.

Emotion processing and theory of mind in schizophrenia patients and their unaffected first-degree relatives

Previous studies have suggested that social cognition is affected in individuals with schizophrenia. The purpose of this study was to explore to what extent social cognition deficits are shared by unaffected first-degree relatives, and the nature of the relationship between performance in different paradigms of social cognition. 20 Schizophrenia patients (7 females, 31+/-10 years), 20 healthy age- and gender-matched individuals, 20 unaffected first-degree relatives of the schizophrenia patients (11 females, 50+/-20 years), and 20 healthy individuals matched for age and gender were recruited. Patients showed deficits in the detection of social Faux Pas (0.80+/-0.17 vs. controls: 0.94+/-0.09, p=0.025) and the correct identification of Theory of Mind stories (0.71+/-0.13 vs. controls: 0.82+/-0.12, p=0.038). Relatives performed poorly in the Faces Test (0.83+/-0.14 vs. controls: 0.9+/-0.08, p=0.048), the Reading the Mind in the Eyes Test (0.59+/-0.17 vs. controls: 0.71+/-0.14, p=0.046) and the detection of social Faux Pas (0.8+/-0.2 vs. controls: 0.93+/-0.09, p=0.024). Abnormalities were independent of age, years of education, and general cognitive performance in patients and their relatives. Performance in an Emotion Processing task (Faces Test) was correlated with performance in theory of mind tests in healthy individuals and relatives of patients with schizophrenia only. These results suggest that schizophrenia patients and their unaffected first-degree relatives display similar but nonidentical patterns of social cognition processing.

Quantitative assessment of attribution of intentions to others in schizophrenia using an ecological video-based task: a comparison with manic and depressed patients

Schizophrenia is characterized by the impairment of several facets of social cognition. This has been demonstrated in numerous studies that focused on specific aspects of social cognition such as the attribution of intentions, emotions, or false beliefs to others. However, most of these studies relied on complex verbal descriptions or impoverished social stimuli. In the present study, we evaluated a new task (Versailles-Situational Intention Reading, V-SIR) that is based on video excerpts depicting complex real-life scenes of social interactions. Subjects were required to rate the probabilities of several affirmations of the intentions of one of the characters. The V-SIR task was administered to schizophrenic patients (N=15), depressed patients (N=12), manic patients (N=15), and healthy controls (N=15). The performance of schizophrenic patients was significantly impaired in comparison to healthy and depressed subjects. There was a trend toward a significant difference between schizophrenic and manic patients. Manic patients also demonstrated impaired performance relative to healthy subjects. Schizophrenic patients' V-SIR scores were significantly correlated with their scores on another attribution of intentions task that used comic strips. These results show that tasks based on more ecological stimuli are powerful enough to detect theory-of-mind abnormalities in pathological populations such as schizophrenic patients.

Does disturbance of self underlie social cognition deficits in schizophrenia and other psychotic disorders?

AIM

Although the different approaches to psychosis research have made significant advances in their own fields, integration between the approaches is often lacking. This paper attempts to integrate a strand of cognitive research in psychotic disorders (specifically, social cognition research) with phenomenological accounts of schizophrenia and other psychotic disorders.

METHOD

The paper is a critical investigation of phenomenological models of disturbed selfhood in schizophrenia in relation to cognitive theories of social cognition in psychotic disorders.

RESULTS

We argue that disturbance of the basic sense of self, as articulated in the phenomenological literature, may underlie the social cognition difficulties present in psychotic disorders. This argument is based on phenomenological thinking about self-presence ('ipseity') being the primary or most basic ground for the intentionality of consciousness - that is, the directedness of consciousness towards others and the world. A disruption in this basic ground of conscious life has a reverberating effect through other areas of cognitive and social functioning. We propose three routes whereby self-disturbance may compromise social cognition, including dissimilarity, disruption of lived body and disturbed mental coherence.

CONCLUSIONS

If this model is supported, then social cognition difficulties may be thought of as a secondary index or marker of the more primary disturbance of self in psychotic disorders. Further empirical work examining the relationship between cognitive and phenomenological variables may be of value in identifying risk markers for psychosis onset, thus contributing to early intervention efforts, as well as in clarifying the essential psychopathological features of schizophrenia and other psychotic disorders.

Integration of emotional and cognitive aspects of theory of mind in schizophrenia and its relation to prefrontal neurocognitive performance

INTRODUCTION

There is substantial evidence that patients with schizophrenia present with impaired Theory of Mind (ToM). Whereas previous studies have focused on general ToM abilities, the present study is aimed at testing the underlying behavioural and neurocognitive mechanisms of the impaired integration of affective and cognitive aspects of ToM (the integration of emotional information with mentalising) in patients with schizophrenia.

METHODS

Twenty-six patients with schizophrenia and 35 healthy controls were tested on two ToM tasks involving the integration of affective and cognitive ToM abilities: "Faux Pas" and "reading the mind in the eyes" tasks. To assess the neurocognitive bases of impaired ToM, the ID/ED test (intradimensional/extradimensional shifting test from the CANTAB) was administered.

RESULTS

Patients performed poorly on both the cognitive-affective integration ToM tasks and the ID/ED task as compared to controls. Furthermore, patients' ToM scores were selectively correlated with the reversal trials, which are believed to be associated with orbitofrontal functioning. In addition, more than 50% of the variance in recognising and understanding Faux Pas could be explained by patients' symptomatology. Performance on orbitofrontal related tasks was correlated with subjects' Faux Pas scores in the patients group, but not in the healthy control group.

CONCLUSIONS

Schizophrenic patients appear to have considerable impairment in affective and cognitive ToM integration, which may be related to orbitofrontal dysfunction. These results are in line with previous findings regarding empathy and the importance of the orbitofrontal area in the integration of cognition and affect.

[Neuropsychology and psychopathology: cognitive analysis during medically refractory epilepsy surgery]

In psychopathology, few studies have been focused on the psychiatric complications of medically refractory mesial temporal lobe epilepsy (MTLE). The aim of the present study was to study NG's capacities, who presented emotional change after right temporal epilepsy surgery with phobias and empathy disorders. NG was examined in two emotional judgment tasks: one explicit and another implicit. For negative stimuli, NG had attraction in the explicit task and dependency in the implicit task. This study suggests that surgical intervention might be one of the causes of postoperative psychiatric disorders in patients with MTLE. MTLE patients have to be explored with neuropsychological paradigms.

Theory of mind deficits in chronic schizophrenia: evidence for state dependence

There is evidence that people with schizophrenia show specific deficits in theory of mind (ToM). However, it is a matter of debate whether these are trait or state dependent, and the nature of the relationship between ToM deficits and particular symptoms is controversial. This study aimed to shed further light on these issues by (1) examining ToM abilities in 61 individuals with chronic schizophrenia during a stable phase as compared with 51 healthy controls matched by gender, age, educational level and current IQ, and (2) exploring the relationship between ToM and symptoms. Second order verbal stories and a non-verbal picture-sequencing task were used as ToM measures. Results showed no differences in ToM performance between patients and controls on either measure. Subsequent subgrouping of patients into remitted and non-remitted showed a worse performance of non-remitted patients only on second order ToM tasks. Specific ToM deficits were found associated with delusions. Association with negative symptoms was found to be less specific and accounted for by illness chronicity and general cognitive impairment. The results from the present study are in line with models which hypothesise that specific ToM deficits in schizophrenia are state dependent and associated with delusions. Such associations may also be task specific.

Kognitive Verhaltenstherapie von Wahn und Halluzinationen

Zusammenfassung. Theoretischer Hintergrund: In den letzten 10-15 Jahren sind eine Reihe von kognitiv-behavioralen Interventionen entwickelt und evaluiert worden, die auf eine direkte Reduktion von Wahn und Halluzinationen abzielen. Gleichzeitig mehren sich Arbeiten aus der Grundlagenforschung zu Schizophrenie, die darauf hindeuten, dass Wahn und Halluzinationen mit spezifischen kognitiven Verarbeitungsstilen assoziiert sind. Als solche gelten unter anderem voreiliges Schlussfolgern, Schwierigkeiten in der Perspektivenübernahme (Theory-of-Mind), external-personale Attributionsstile und fehlerhafte Quellenattribution. Ziele: 1) die wichtigsten experimentellen Untersuchungen und Ergebnisse zu kognitiven Prozessen bei Wahn und Halluzinationen verständlich darzustellen, 2) eine Einführung in die therapeutischen Interventionen zur Veränderung der Symptome zu bieten und 3) zu bewerten, inwieweit die experimentellen Befunde in die Entwicklung von Therapiestrategien zu Wahn und Halluzinationen eingeflossen sind, bzw. durch spezifische Befunde gedeckt werden. Schlussfolgerungen: Die Mehrzahl der Interventionen setzt indirekt an den gefundenen kognitiven Auffälligkeiten an, wobei offen bleibt, in wie weit ihre Wirkung auf eine Veränderung der kognitiven Verarbeitungsstile zurückgeht. Obwohl die kognitive Umstrukturierung dysfunktionaler Selbstkonzepte einen wesentlichen Bestandteil der kognitiven Interventionen darstellt, ist die empirische Evidenz für die Rolle negativer Selbstkonzepte bei der Entstehung von Wahn und Halluzinationen bislang uneindeutig.

Theory of mind in schizophrenia: meta-analysis

BACKGROUND

Mentalising impairment (an impaired ability to think about people in terms of their mental states) has frequently been associated with schizophrenia.

AIMS

To assess the magnitude of the deficit and analyse associated factors.

METHOD

Twenty-nine studies of mentalising in schizophrenia (combined n=1518), published between January 1993 and May 2006, were included to estimate overall effect size. Study descriptors predicted to influence effect size were analysed using weighted regression-analysis techniques. Separate analyses were performed for symptom subgroups and task types.

RESULTS

The estimated overall effect size was large and statistically significant (d=-1.255, P<0.0001) and was not significantly affected by sample characteristics. All symptom subgroups showed significant mentalising impairment, but participants with symptoms of disorganisation were significantly more impaired than the other subgroups (P<0.01).

CONCLUSIONS

This meta-analysis showed significant and stable mentalising impairment in schizophrenia. The finding that patients in remission are also impaired favours the notion that mentalising impairment represents a possible trait marker of schizophrenia.

Dissociation of cognitive from affective components of theory of mind in schizophrenia

Patients suffering from schizophrenia show impaired emotional and social behavior, such as misinterpretation of social situations and lack of theory of mind. However, there is conflicting evidence regarding their ability to perform on theory of mind tasks. Based on previous findings with patients suffering from prefrontal damage, the present study suggests that the behavioral deficit of schizophrenic patients may be due to impaired 'affective theory of mind' abilities, rather than to a general impairment in theory of mind. To test this hypothesis we assessed the ability of 22 schizophrenic patients and 55 age-matched healthy controls, to judge first and second order affective vs. cognitive mental state attribution, based on eye gaze. The relationships between negative and positive symptoms of schizophrenia, and affective and cognitive theory of mind were also assessed. Results indicated that while healthy controls made fewer errors on affective as compared to cognitive theory of mind conditions, schizophrenic patients showed a less prominent trend. Although the pattern of reaction time did not differ significantly between groups, the patients made significantly more errors in the affective conditions, as compared to controls. Furthermore, correlation analysis indicated that impaired affective theory of mind in these patients correlated with their level of negative symptoms. These results indicate that individuals with high level of negative symptoms of schizophrenia may demonstrate selective impairment in their ability to attribute affective mental states. These findings offer new insight into the affective facets of social behavior that may underlie the profound behavioral disturbances observed in schizophrenia.

A study of theory of mind in a group of schizophrenic patients using a mental verb extension task

An individual has a theory of mind (ToM) if he imputes mental states to himself and others and applies this system to make predictions about the behaviours of others. Findings of cognitive impairment could help us to understand faulty processing mechanisms in schizophrenia. The proposition is that individuals with schizophrenia may be unable to internalize adequately the points of view of others. We tested 27 schizophrenic patients (ICD; WHO). The positive and negative symptom scale (PANSS) was used to assess psychopathology, and the three ToM tasks--first- and second-order false belief tasks and the mental verb extension task--were administered to each subject. Patients who perform well on the ToM first and second order stories do not show problems in the verb extension task. However, the mistakes made in the first and second order stories are also reflected in the verb extension task. The group having difficulties with the first-order story presented more problems in the mental verbs task than the group showing difficulties with the second-order story. This leads us to conclude that the impairments found on the first-order false belief task are more severe and profound than those on the second-order task, and such specific deficits are also seen in the organization of verbs of knowing. It would seem that some schizophrenic patients do not impute mental states to themselves and others, and therefore use the mental verbs wrongly.

Social Cognition: An Early Impairment in Dementia of the Alzheimer Type

OBJECTIVE

A core component of social functioning is the capacity to attribute mental states to others and to understand intention as psychologic cause. The hypothesis of this study was that dementia of the Alzheimer type (DAT) patients show an impaired understanding of psychologic cause although they remain able to understand physical causality.

METHODS

To test this hypothesis, 20 elderly adults with DAT, 20 healthy age-matched controls, and 20 healthy young adults were presented a cartoon task requiring them to process physical or psychologic cause of events.

RESULTS

Patients with DAT at onset scored significantly lower than controls when they had to reason about psychologic causation, while they did not differ for reasoning about physical causation. Consistent with these results, patients with DAT showed significantly lower scores in psychologic reasoning as compared with their scores for physical causality. Instead young and elderly healthy adults scored similarly for the 2 types of causality and the 2 groups did not differ in their scores. These results suggest that impaired understanding of intention in others may be considered as an early socio-cognitive index of onset of DAT. A post hoc division of the group of patients with DAT into 2 subgroups according to Mini Mental State (MMS) scores showed that the group with the more severe MMS scores not only had lower scores for psychologic causality but also showed impairment in reasoning about physical causality involving persons. Physical causality involving objects remained relatively preserved.

CONCLUSIONS

The remarkable deficit in attribution of intention in our patients with DAT at onset and the following deterioration of their performance in reasoning about physical causality with persons may reflect progressive dysfunction of the superior temporal sulcus in Alzheimer disease.

Social brain dysfunctions in schizophrenia: a review of neuroimaging studies

Several studies have indicated that schizophrenic patients show impaired performance in various aspects of social cognition, including theory of mind, emotion processing, and agency judgments. Neuroimaging studies that have compared patients and healthy subjects during such mental activity indicate an abnormal hemodynamic response in the medial prefrontal cortex, the prefrontal cortex, the amygdala, the inferior parietal lobe, i.e., a set of regions known to be critically involved in social cognition. This paper addresses a number of issues raised by schizophrenia research into theory of mind, emotion perception and self-agency with regards to the neural systems that mediate social cognition. In healthy subjects, typical brain patterns are associated with theory of mind, emotion perception and self-agency; some activated clusters overlap, while others are distinct. For instance, activations in the paracingulate gyrus are almost systematically associated with theory of mind tasks, while the amygdala is mainly involved in emotion perception tasks. Additional foci are frequently found activated during those tasks: superior temporal sulcus, inferior frontal area. Moreover, the inferior parietal lobe is thought to contribute to agency judgments. In the light of the data on brain abnormalities and neurochemical dysfunctions in schizophrenia, we discuss the interaction of social cognitive dysfunction with the supposed information processing abnormalities caused by dopamine dysregulation.

Naive theory impairment in schizophrenia: is it domain-specific?

The ability to represent mental states of self and others to account for behavior is called theory of mind (ToM). This study examined whether ToM deficit in schizophrenia patients is a specific deficit in the cognitive component of interpersonal skills or a more global deficit, involving impaired information processing skills. Schizophrenia inpatients (N = 41) were compared with a control group of healthy subjects (N = 22) and to nonschizophrenia psychiatric patients (24 with affective disorders, seven with other psychosis) over a range of ToM tasks and another naive theory (theory of biology; ToB). Psychiatric inpatients as a whole showed significant deficit compared with the control group of healthy subjects in ToM tasks. The schizophrenia patients showed significantly larger deficits compared with patients suffering from affective disorder, while the performance of patients with nonschizophrenia psychosis was intermediate. In contrast, no difference was observed in the performance of the different groups on the ToB tasks. The fact that a deficit was found in ToM but not in ToB suggests a specific deficit in a cognitive component of interpersonal skills in schizophrenia rather than a general deficit in information processing skills. Naive theories deficits in schizophrenia seem to be domain-dependent.

Social-Cognitive Functioning and Schizotypal Characteristics

The authors examined the relationship between social cognition and a feature of schizotypal personality referred to as magical ideation, defined broadly as the presence and intensity of illogical beliefs about causality and the nature of reality. The measures of social cognition used in this study were the Character Intention Task (CIT) and the adult version of the Reading the Mind in the Eyes Test. Regression analyses indicated that understanding of character intentions, as measured by CIT scores, and ability to identify emotions on the Eyes test were related to non-realistic beliefs. Principal components analysis of the Magical Ideation Scale generated 3 factors: Occult Beliefs, Non-Realism, and New Age Ideas. Results indicated that impaired understanding of character intentions and ability to identify emotions on the Eyes test were related to non-realistic beliefs. Understanding the cognitive impairments associated with schizotypal characteristics can facilitate development of more targeted therapeutic interventions.

Theory of mind and its relation to schizotypy

INTRODUCTION

Frith (1992) suggested that many psychotic symptoms are associated with impaired theory of mind (ToM), the ability to represent the mental states of others. Langdon and Coltheart (1999) found an association in a nonclinical adult population between schizotypal traits and poorer ToM on a picture-sequencing task. The present study attempted to replicate and extend this finding using a ToM story task.

METHODS

A total of 62 nonclinical individuals completed a schizotypy questionnaire (the Oxford-Liverpool Inventory of Feelings and Experiences; O-LIFE) and a set of ToM stories. Matched "physical" control stories were administered to control for general reasoning ability. Executive function and current verbal IQ were assessed using the Cognitive Estimates Test and the Quick Test, respectively.

RESULTS

Schizotypal traits analogous to positive symptoms of schizophrenia (UE scale of the O-LIFE) predicted poorer scores on the ToM task, but were unrelated to scores on physical stories. Individuals with high scores for total schizotypy on the O-LIFE did not differ in ToM from those with low total scores. There was no association between poorer ToM and schizotypal traits analogous to the "behavioural signs" of schizophrenia. Executive function and verbal IQ did not significantly predict story scores.

CONCLUSIONS

Positive schizotypal traits in the normal population are associated with subtle impairments in ToM, independent of reasoning ability, executive function, or verbal IQ. A strong association between poor ToM and "behavioural signs" may only appear in studies of schizophrenic patients, and not in studies of nonclinical individuals. The findings are discussed in relation to Frith's (1992) cognitive neuropsychological model of schizophrenia.

Elaboration of a rehabilitation method based on a pathogenetic hypothesis of “theory of mind” impairment in schizophrenia

"Theory of mind" skills have repeatedly been shown to be impaired in schizophrenic patients. The purpose of this paper is to develop a therapeutic intervention targeting schizophrenic patients' abilities to attribute mental states to others. This preliminary study tried to test the hypothesis that this kind of intervention should improve patients' communication abilities; we also wondered if this would have a positive impact on their more general psychopathology. Eight chronic schizophrenic patients were asked to analyse video scenes (showing interactions between two or more persons), with particular attention being paid to the characters' mental states. Their clinical assessments (general clinical symptoms, communication, and the ability to attribute intentions to others, rated before and after two training sessions, over a one-week period) were compared with those of a control group of six chronic schizophrenic patients. The results support our hypothesis of a possible improvement of patients' communication disorders and an improvement of their abilities to attribute intentions to others. The more general psychopathology ratings, however, remained unchanged. Although these results need further development and confirmation, they suggest a possible promising approach for psychosocial rehabilitation therapies based on "theory of mind" skills.

Social cognition and symptom dimensions

This study used the Picture Arrangement subtest of the Wechsler Adult Intelligence Scale to assess social cognitive functioning of psychotic patients diagnosed with bipolar, schizophrenia, or schizoaffective disorder. All participants were rated on positive and negative symptom rating scales, from which three symptom dimensions were obtained. Symptom dimensions were not significantly related to ratings of symptom severity or mental status examination scores. Disorganized symptoms were correlated with a wide range of impairments on nearly all subscale measures of social cognition. Negative symptoms were correlated with lower ratings of capacity for emotional investment, complexity of representations, and integration of episodes. Psychoticism was associated with negative affect tone. Diagnostic categories were not related to social cognitive impairments independent of estimates of premorbid level of cognitive function. Evidence of syndromal differences suggests that heterogeneity of variance in studies of functioning of schizophrenic patients can be reduced by inclusion of symptom dimensions.

Scale for the evaluation of communication disorders in patients with schizophrenia: a validation study

OBJECTIVE

A scale for the evaluation of communication disorders in patients with schizophrenia (Schizophrenia Communication Disorder Scale-SCD) is proposed based on studies showing that cognitive disorders specific to the disorganization seen in schizophrenia consist of context processing deficits and problems in the attribution of mental states. Thus the focus of this scale is on the cognitive difficulties revealed in conversation during a structured interview.

METHOD

Fifty-six patients with schizophrenia, depression or mania were evaluated.

RESULTS AND CONCLUSION

Significantly elevated scores on the SCD were present in patients with schizophrenia compared to all other groups. Thus, this scale adds to the tools available for evaluating the language of patients with schizophrenia and helps focus on characteristics that are specific to this psychotic diagnosis.

Theory of mind in schizophrenia: a critical review

INTRODUCTION

Frith's (1992) neuropsychological theory of schizophrenia posits a number of fundamental cognitive impairments underpinning the characteristic symptoms of this disorder. One of these is an impairment in the ability to correctly interpret and predict the mental states of other people, so-called theory of mind (ToM). There is already a substantial body of evidence that ToM is impaired in people with schizophrenia. Our aim was to critically review this literature.

METHOD

A narrative review of the research literature was completed. Electronic searches of both Medline and PsycInfo were conducted to locate relevant articles. The bibliographies of relevant articles were scrutinised and in some cases researchers were contacted directly.

RESULTS

A total of 30 studies that all examined some aspect of ToM in people with schizophrenia were located. These were summarised and key issues on this topic were identified.

CONCLUSIONS

There is considerable evidence that ToM is impaired in people with schizophrenia. However, this is perhaps the only unequivocal finding on the topic to date. Issues that demand further clarification include: Is the deficit a state or a trait? How to measure ToM in schizophrenia research, and whether certain symptoms or groups of symptoms are associated with the ToM deficit. These issues are considered and the evidence evaluated. Some priorities for future research are suggested.

Schizophrenia, theory of mind, and persecutory delusions

INTRODUCTION

There is already a substantial body of evidence supporting Frith's (1992) theory that theory of mind (ToM) is impaired in people with schizophrenia. However, a specific relationship between impaired ToM and paranoid delusions, while intuitively reasonable, has only been demonstrated in two studies to date.

METHODS

A total of 25 participants with schizophrenia were classified as paranoid or nonparanoid and compared with 38 healthy controls on a variety of ToM tasks. These tasks included verbal and nonverbal, and first and second order ToM tasks.

RESULTS

Participants with schizophrenia performed significantly more poorly than healthy controls on both the first and second order verbal ToM tasks but not on the nonverbal ToM tasks. However, the ToM deficit was only observed for those participants with schizophrenia who had persecutory delusions. There was also a strong relationship observed between the severity of persecutory delusions and length of illness.

CONCLUSIONS

This study represents only the third demonstration of a specific link between paranoid delusions and ToM impairment. Reasons why previous findings on this issue have been so inconsistent are considered. Further research is needed to explore the relationships among paranoia, ToM, and length of illness.

Thematic Reasoning and Theory of Mind. Accounting for Social Inference Difficulties in Schizophrenia

Background

Corcoran (2000, 2001) has suggested that theory of mind judgements can be arrived at using analogical reasoning skills and she has proposed that this is the route that people with schizophrenia take when they make inferences about others' mental states. Recent work has demonstrated a robust relationship between mental state inference and autobiographical memory, providing initial support for the model. This study examines the model further by exploring the assertion that in schizophrenia the ability to infer the mental states of others also depends upon effective social reasoning in conditional contexts.

Method

59 people with a DSM IV diagnosis of schizophrenia and 44 healthy subjects performed four versions of the thematic selection task. The versions varied according to the familiarity and social nature of the material they incorporated. The same subjects also completed the Hinting Task, a measure of theory of mind and tests of intellectual functioning and narrative recall.

Results

The schizophrenia and the normal control groups differed in their performance on all of the measures except that of intellectual functioning. Explorations within the schizophrenia group indicated that social reasoning was most markedly affected in the patients with negative signs and in those with paranoid delusions while for the hinting task, those with negative signs performed significantly worse than those in remission but this difference seemed to be due to these patients' poorer narrative memory. There was evidence in the schizophrenia data to support the hypothesis of a relationship between theory of mind and social conditional reasoning.

Conclusion

This work provided further support for the idea that in patients with schizophrenia at least, judgements about the mental states of others are achieved using analogical reasoning.

Attention, theory of mind, and causal attributions in people with persecutory delusions: A preliminary investigation

INTRODUCTION

Abnormal attributions and deficits in theory of mind (ToM) skills have been implicated in paranoid delusions. Bentall and Kinderman (1998) have proposed that ToM deficits tend to prevent individuals from making situational attributions and therefore increase the probability of external-personal attributions, which in turn lead to paranoid beliefs. They further suggested that more fundamental information-processing deficits, by affecting theory of mind skills, increase the probability of paranoid attributions.

METHODS

Relationships between attention, ToM and attributions were assessed in acute and remitted paranoid patients and normal controls. Participants performed the digit span with distraction task, false belief and deception tasks, and a measure of attributional style.

RESULTS

Compared to the controls, acute patients were distractible, performed poorly on ToM, and made more attributions that were judged external-personal by independent raters (but not as judged by self-ratings). ToM scores predicted the number of external-personal attributions as expected, but the effect of distraction on ToM was equivocal.

CONCLUSIONS

Preliminary support was found for the hypotheses, but further studies are required using a range of executive, attentional, ToM, and attribution measures.

Abnormalities of brain function during a nonverbal theory of mind task in schizophrenia

Theory of mind (ToM), the specific ability to attribute thoughts and feelings to oneself and others is generally impaired in schizophrenia. Previous studies demonstrated a deficit of the attribution of intentions to others among patients having formal thought disorder. During nonverbal tasks, such a function requires both the visual perception of human figures and the understanding of their intentions. These processes are considered to involve the superior temporal sulcus and the medial prefrontal cortex, respectively. Are the functional patterns of activation associated with those processes abnormal in schizophrenia? Seven schizophrenic patients on medication performed a nonverbal attribution of intentions task as well as two matched physical logic tasks, with and without human figures, while H2O15 PET-scanning was performed. Data from the patients were compared to those of eight healthy controls matched for verbal IQ and sex. The experimental design allowed dissociating the effect of the perception of human figures from that of the attribution of intentions. During attribution of intentions, significant activations in the right prefrontal cortex were detected in the control subjects. Those activations were not found in the schizophrenic group. However, in both groups, the perception of human figure elicited bilateral activation of the occipitotemporal regions and of the posterior part of the superior temporal sulcus. Schizophrenic patients performing a nonverbal attribution of intentions task have an abnormal cerebral activity.

Peeling the onion: NMDA dysfunction as a unifying model in schizophrenia

N-methyl-d-aspartate receptor (NMDAR) dysfunction plays a crucial role in schizophrenia, leading to impairments in cognitive coordination. NMDAR agonists (e.g., glycine) ameliorate negative and cognitive symptoms, consistent with NMDAR models. However, not all types of cognitive coordination use NMDAR. Further, not all aspects of cognitive coordination are impaired in schizophrenia, suggesting the need for specificity in applying the cognitive coordination construct.

High-frequency synchronisation in schizophrenia: Too much or too little?

Phillips & Silverstein's focus on schizophrenia as a failure of “cognitive coordination” is welcome. They note that a simple hypothesis of reduced Gamma synchronisation subserving impaired coordination does not fully account for recent observations. We suggest that schizophrenia reflects a dynamic compensation to a core deficit of coordination, expressed either as hyper- or hyposynchronisation, with neurotransmitter systems and arousal as modulatory mechanisms.

No blind schizophrenics: Are NMDA-receptor dynamics involved?

Numerous searches have failed to identify a single co-occurrence of total blindness and schizophrenia. Evidence that blindness causes loss of certain NMDA-receptor functions is balanced by reports of compensatory gains. Connections between visual and anterior cingulate NMDA-receptor systems may help to explain how blindness could protect against schizophrenia.