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Theory of mind impairments in patients with deficit schizophrenia
... Our findings regarding sociodemographic and clinical differences between DS and NDS subjects were also in general agreement with those reported in previous studies, however, the extant literature has provided mixed results that require a specific discussion. Thus, while several authors have also reported that DS patients have a significantly lower education level and a greater proportion of nonparanoid forms of schizophrenia than NDS patients [36][37][38][39][40], other studies have not found such differences [17,18,[41][42][43]. Similarly, our findings regarding the lack of gender differences between DS and NDS contradict metaanalytic evidence supporting the notion that male gender is associated with DS [44]. ...
... Similarly, our findings regarding the lack of gender differences between DS and NDS contradict metaanalytic evidence supporting the notion that male gender is associated with DS [44]. Nevertheless, although our sample may have lacked statistical significance due to its small size, other authors have not found associations between DS and male gender either [17,20,38,41]. Mixed findings on age at onset of psychosis and the likelihood of DS have also been observed. ...
... Mixed findings on age at onset of psychosis and the likelihood of DS have also been observed. In this vein, our results were in agreement with the findings of previous studies [17,18,38,41,43], but were contrary to those found in others in which DS was linked to a younger age at onset of schizophrenia symptoms [42,[45][46][47]. We did not find an association between DS and duration of psychotic illness in our sample either, similar to reports by other authors [17,38,41,43], and support the classic conceptualization of DS as a separate disease within the schizophrenia spectrum [20]. ...
Background: Cumulative evidence has demonstrated important differences between deficit (DS) and non-deficit (NDS) schizophrenia, suggesting that DS may be a separate disease. However, most data come from the same research groups and more replication is needed to validate this hypothesis.
Aims: Our study aimed to examine the distribution of DS, to compare their characteristics with NDS patients and to analyze the reliability of the two-factor structure of its negative symptomatology in a Spanish clinical sample.
Methods: Sixty clinically stabilized patients with schizophrenia were evaluated. The Schedule for the Deficit Syndrome was used for DS/NDS categorization. Patient characteristics included age, gender, education, age at onset of psychosis, duration of illness, family history of psychosis, type of antipsychotic regimen, schizophrenia subtype and severity of the disease.
Results: DS prevalence was 28.3%. Bivariate analysis revealed statistical differences between DS and NDS in terms of years of education and schizophrenia subtype. Factor analysis replicated the two-factor solution consisting of the ‘Expressive deficit’ and ‘Avolition–apathy’ domains reported in previous studies.
Conclusions: Our results were consistent with the published data and indicated that the DS profile in the Spanish population is similar to that in other populations, which would corroborate the homogeneity of DS within the schizophrenia spectrum and contribute to the hypothesis that DS constitutes a separate disease.
... Social cognition impairment is a key domain in schizophrenia related to negative symptoms and affects daily functioning and quality of life [2,23,24]. The "Reading the Mind in the Eyes Test (RMET)" and the faux-pas test are sensitive measures of theory of mind and social cognition in schizophrenia. ...
... The latter two factors lead to considerable ambiguity of social information that can be solved by active mentalization. A further advantage of the RMET is that numerous schizophrenia studies have applied this measure so far and confirmed that RMET is a reliable tool to detect differences in ToM between patients with schizophrenia and healthy controls [2,23]. ...
Background
Treatment effects of conventional approaches with antipsychotics or psychosocial interventions are limited when it comes to reducing negative and cognitive symptoms in schizophrenia. While there is emerging clinical evidence that new, augmented protocols based on theta-burst stimulation can increase rTMS efficacy dramatically in depression, data on similar augmented therapies are limited in schizophrenia. The different patterns of network impairments in subjects may underlie that some but not all patients responded to given stimulation locations.
Methods
Therefore, we propose an augmented theta-burst stimulation protocol in schizophrenia by stimulating both locations connected to negative symptoms: (1) the left dorsolateral prefrontal cortex (DLPFC), and (2) the vermis of the cerebellum. Ninety subjects with schizophrenia presenting negative symptoms and aging between 18 and 55 years will be randomized to active and sham stimulation in a 1:1 ratio. The TBS parameters we adopted follow the standard TBS protocols, with 3-pulse 50-Hz bursts given every 200 ms (at 5 Hz) and an intensity of 100% active motor threshold. We plan to deliver 1800 stimuli to the left DLPFC and 1800 stimuli to the vermis daily in two 9.5-min blocks for 4 weeks. The primary endpoint is the change in negative symptom severity measured by the Positive and Negative Syndrome Scale (PANSS). Secondary efficacy endpoints are changes in cognitive flexibility, executive functioning, short-term memory, social cognition, and facial emotion recognition. The difference between study groups will be analyzed by a linear mixed model analysis with the difference relative to baseline in efficacy variables as the dependent variable and treatment group, visit, and treatment-by-visit interaction as independent variables. The safety outcome is the number of serious adverse events.
Discussion
This is a double-blind, sham-controlled, randomized medical device study to assess the efficacy and safety of an augmented theta-burst rTMS treatment in schizophrenia. We hypothesize that social cognition and negative symptoms of patients on active therapy will improve significantly compared to patients on sham treatment.
Trial registration
The study protocol is registered at “ClinicalTrials.gov” with the following ID: NCT05100888. All items from the World Health Organization Trial Registration Data Set are registered. Initial release: 10/19/2021.
... Social cognition impairment is a key domain in schizophrenia related to negative symptoms and affects daily functioning and quality of life [2,23,24]. The "Reading the Mind in the Eyes Test (RMET)" and the faux-pas test are sensitive measures of theory of mind and social cognition in schizophrenia. ...
... The latter two factors lead to considerable ambiguity of social information that can be solved by active mentalization. A further advantage of the RMET is that numerous schizophrenia studies have applied this measure so far and con rmed that RMET is a reliable tool to detect differences in ToM between patients with schizophrenia and healthy controls [2,23]. ...
Background
Treatment effects of conventional approaches with antipsychotics or psychosocial interventions are limited when it comes to reducing negative and cognitive symptoms in schizophrenia. While there is emerging clinical evidence that new, augmented protocols based on theta-burst stimulation can increase rTMS efficacy dramatically in depression, data on similar augmented therapies are limited in schizophrenia. The different patterns of network impairments in subjects may underlie that some but not all patients responded to given stimulation locations.
Methods
Therefore, we propose an augmented theta-burst stimulation protocol in schizophrenia by stimulating both locations connected to negative symptoms: (1) the left Dorsolateral Prefrontal Cortex (DLPFC), and (2) the vermis of the cerebellum. Ninety subjects with schizophrenia presenting negative symptoms and aging between 18–55 years will be randomized to active and sham stimulation in a 1:1 ratio. The TBS parameters we adopted follow the standard TBS protocols, with 3-pulse 50-Hz bursts given every 200 ms (at 5 Hz) and an intensity of 100% active motor threshold. We plan to deliver 1800 stimuli to the left DLPFC and 1800 stimuli to the vermis daily in two 9.5-minute blocks for four weeks. The primary endpoint is the change in negative symptom severity measured by the Positive and Negative Syndrome Scale (PANSS). Secondary efficacy endpoints are changes in cognitive flexibility, executive functioning, short-term memory, social cognition, and facial emotion recognition. The safety outcome is the number of serious adverse events.
Discussion
This is a double-blind, sham-controlled, randomized medical device study to assess the efficacy and safety of an augmented theta-burst rTMS treatment in schizophrenia. We hypothesize that social cognition and negative symptoms of patients on active therapy will improve significantly compared to patients on sham treatment.
Trial registration
The study protocol is registered at 'clinicaltrials.gov 'with the following ID: NCT05100888. All items from the World Health Organization Trial Registration Data Set are registered. Initial release: 10/19/2021.
... This question is worthy of study, because schizophrenia patients with a so-called "deficit syndrome" show distinct socio-cognitive deficits including limited emotional responsivity and problems in dealing with complex social situations (22,23). Deficit schizophrenia is also associated with deviant discrimination of facial affect (24), poor ToM compared to non-deficit patients (25), as well as diminished empathy and self-confidence (26). ...
... Deficits in social cognition and aberrant neurocognition are known to affect social functioning (40). To our knowledge, there is a paucity of research addressing social cognition in the most severely and chronically ill patients with schizophrenia (24,25). ...
Aberrant social behavior is a frequent clinical feature of schizophrenia and seems related to the duration and chronicity of the disorder. However, there is a paucity of research into the relationship between social behavior and social cognition in patients with severe chronic courses of schizophrenia. Accordingly, the present study sought to examine the appreciation of social rules and norms such as fairness and cooperation in schizophrenia patients who fulfilled the criteria for “deficit syndrome”. To this end, we utilized a so-called Ultimatum Game, and a Dictator Game, in which participants had the option to punish others’ unfair behavior. In addition, “theory of mind”, the ability to appreciate others’ mental states, was also examined using the Mental State Attribution Task (MSAT). Symptom severity was determined using the Positive and Negative Syndrome Scale. While patients with deficit schizophrenia responded to varying levels of fairness in similar ways to controls, the patients accepted fewer fair offers and engaged less in third-party punishment. Impaired theory of mind in patients reduced the latter, but not the former, group difference to non-significance. No significant correlations emerged between symptom severity and task performance. Together, these findings suggest that the understanding of others’ minds partly contributes to the appreciation of social rules and norms in patients with severe chronic courses of schizophrenia.
... An earlier review showed that although deficit patients performed more poorly on cognitive tests than non-deficit counterparts, most were non-significant and effect size for those found to be significant was small, and was mainly related to social cognition (Cohen et al., 2007). More recent data revealed significant associations of deficit syndrome with either generalized cognitive dysfunction (Rethelyi et al., 2012;Wang et al., 2008) or impairment in specific cognitive domains including executive function (Csukly et al., 2014;Szendi et al., 2010), processing speed (Chen et al., 2014), memory (Ahmed et al., 2014;Hovington et al., 2013), and attention (Chen et al., 2014;Pegoraro et al., 2013). Conversely, very few FEP studies were conducted in this respect, and most investigated the predictive capacity of baseline cognitive functions on the development of persistent PNS at follow-up, with lack of significant findings being noted (Chang et al., 2011;Galderisi et al., 2013;Malla et al., 2004). ...
... Conversely, very few FEP studies were conducted in this respect, and most investigated the predictive capacity of baseline cognitive functions on the development of persistent PNS at follow-up, with lack of significant findings being noted (Chang et al., 2011;Galderisi et al., 2013;Malla et al., 2004). Our results that PNS was related to performance in MWCST and digit symbol test are, however, in accord with several past studies which demonstrated selective impairments in cognitive flexibility (Csukly et al., 2014;Szendi et al., 2010) and processing speed (Bryson et al., 2001;Cohen et al., 2007) in chronic patients with deficit syndrome. Our final regression model further confirms that digit symbol coding measure is independently associated with PNS. ...
... ToM has been investigated by Langdon et al. [16]. Patients in early stages of psychosis exhibited impairments in picture-sequencing and jokeappreciation, but not in story-comprehension [14]. ...
... Accordingly, ToM deficits might predate conversion to psychosis, but one must consider initial symptoms as well [15 & ]. Csukly et al. [16] examined potential ToM differences between patients suffering from the deficit syndrome or nondeficit schizophrenia, and healthy controls. Control individuals outperformed both patient groups, but there were no significant differences between the two schizophrenia subgroups. ...
Social cognition represents a fundamental skill for effective social behavior. It is nowadays widely accepted that individuals suffering from serious mental illness are impaired in this domain.
Studies published since June 2012 have been reviewed, with a particular focus on theory of mind, social perception, social knowledge, attributional bias, and emotion processing in patients suffering from schizophrenia and mood disorders.
The reviewed literature supports previous studies on deficits in social cognition in schizophrenia, major depressive disorder and bipolar disorder, and underscores their relevance in the psychosocial context.
... The inclusion of EF into the analysis did not contribute to increase the explained variance of the patients' ability to comprehend and produce the various pragmatic phenomena investigated. Only the addition of ToM could significantly increase the explained variance, but only in the INTRODUCTION Since Frith's (1992) theoretical proposal, numerous studies in the literature have reported a theory of mind (ToM) impairment in patients with schizophrenia (Abu-Akel, 1999;Sarfati and Hardy-Baylé, 1999;Bosco et al., 2009;Bliksted et al., 2014;Csukly et al., 2014;Bechi et al., 2018;Vaskinn et al., 2018), which is a difficulty attributing mental states, such as intentions, desires and beliefs, to themselves and others (Premack and Woodruff, 1978). Several reviews and meta-analyses have confirmed this finding. ...
Patients with schizophrenia are often described as impaired in several cognitive domains. Specifically, patients with schizophrenia often exhibit problems in solving tasks requiring theory of mind (ToM), i.e., the ability to ascribe mental states to oneself and others, communicative-pragmatic ability, i.e., the ability to use language and non-verbal expressive means to convey meaning in a given context, and executive functions (EF). This study aims to investigate the role of cognitive functions, such as general intelligence, selective attention, processing speed, and especially EF (working memory, cognitive flexibility, inhibition, and planning), and ToM in explaining the performance of individual with schizophrenia in comprehending and producing communicative acts expressed with different communicative intentions (i.e., sincere, deceitful, and ironic), and realized through linguistic and extralinguistic/non-verbal expressive means. Thirty-two patients with schizophrenia and an equal number of healthy controls performed tasks aiming to investigate their capacity to comprehend and produce sincere, deceitful, and ironic communicative acts in addition to a series of cognitive tasks evaluating EF and ToM. The results indicated that individuals with schizophrenia performed worse than the controls in the comprehension and production of all pragmatic phenomena investigated, as well as in all the cognitive functions examined. The patients with schizophrenia also exhibited an increasing trend of difficulty in comprehending and producing sincere, deceitful, and ironic communicative acts expressed through either linguistic or extralinguistic means. Furthermore, a multiple regression analysis of the patients’ performance on the pragmatic tasks revealed that overall, the role of attention, general intelligence, and processing speed did not appear to significantly explain the patients’ communicative-pragmatic performance. The inclusion of EF into the analysis did not contribute to increase the explained variance of the patients’ ability to comprehend and produce the various pragmatic phenomena investigated. Only the addition of ToM could significantly increase the explained variance, but only in the comprehension and production of deceit expressed by language and the production of sincere communicative acts, also limited to linguistic production. We conclude that neither EF nor ToM are able to explain the decreasing trend detected in the patients’ pragmatic performance.
... Interestingly, in a group of adult patients with schizophrenia, there was a relationship between PANSS positive symptoms and eyes-based basic emotion recognition but not complex state attribution 45 . In another study 46 , no difference was observed between the RMET performance of groups of patients with non-deficit and deficit schizophrenia, with both patient groups being outperformed by healthy controls. Another study by the same research group found an association between negative symptom severity and RMET scores in patients with schizophrenia, both during the acute phase and during remission, but no such relationship for positive symptoms 47 . ...
Social cognition deficits are observed both in patients with schizophrenia (SCZ) and in patients with mesial temporal lobe epilepsy (MTLE). This may be due to dysfunction of the amygdala network, which is a common feature of both diseases. In this study, SCZ (n = 48) or MTLE (n = 31) and healthy controls (HC, n = 47) completed assessments of mentalising (Reading Mind in the Eyes Test, RMET) and basic cognitive processing, e. g., working memory, executive functions and psychomotor speed (Trail-Making Test B and Digit Symbol). SCZ were also assessed with the Positive And Negative Syndrome Scale (PANSS). We found that the RMET scores of the two clinical groups were similar (p > 0.05) and lower than in the HCs (SCZ: p < 0.05; MTLE: p < 0.001). In the next step, SCZ were split into two groups with respect to the level of symptoms. Analysis of the RMET scores revealed no differences between the HC (M = 25.7 +/- 4.1) and POS-LO (M = 25.3 +/- 4.8); both groups outperformed the POS-HI group (M = 21.3 +/- 5.2) and the MTLE group (M = 20.8 +/- 4.6). No differences were found for the median-split with regard to negative symptoms. In SCZ, the mind-reading deficit appears to be associated with the level of positive symptoms. Both POS-HI and MTLE patients present significant mentalising deficits compared to healthy controls.
... Theory of mind has been widely studied in the field of personality disorders (Dimaggio, Nicolò, Semerari, & Carcione, 2013;Semerari et al., 2015), neuropsychological disorders (Di Tella et al., 2015;Enrici et al., 2015), schizophrenia (Csukly, Polgár, Tombor, Benkovits, & Réthelyi, 2014;Lysaker et al., 2011) and autism spectrum disorders (Baron-Cohen et al., 2015;Montgomery et al., 2016). Only recently, literature has focused on the domain of social cognition in patients with eating disorders (EDs), mostly in patients with anorexia nervosa (AN; Adenzato, Todisco, & Ardito, 2012;Oldershaw, Treasure, Hambrook, Tchanturia, & Schmidt, 2011b;Tchanturia et al., 2004) and bulimia nervosa (BN; Dejong et al., 2013;Kenyon et al., 2012;Laghi et al., 2014) with the data from these studies being very controversial. ...
Objective:
This study aims to evaluate the theory of mind ability in a sample of obese patients with and without binge eating disorder (BED) and to explore the correlations between emotional and clinical assessments.
Methods:
Overall, 20 non-BED, 16 under-threshold BED and 22 BED obese patients completed a battery of tests assessing social cognition and eating disorder psychopathology.
Results:
Binge eating disorder, non-BED and under-threshold-BED obese patients showed similar ability to recognise others' emotions, but BED obese patients exhibited a deficit in recognising their own emotions as demonstrated by more impaired levels of alexithymia and interoceptive awareness and were more depressed. High positive correlations were evident between binging, depression, interoceptive awareness and alexithymia.
Conclusions:
Binge eating disorder patients have a comparable ability to understand others' emotions but a more impaired capacity to understand and code their own emotions compared with non-BED obese patients. This impairment is highly correlated with depression. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.
... In sum, 37 pictures must be evaluated, of which the first one is a practice trial which is not evaluated. Using this version of the RMET, several studies have already revealed significant differences between patients with schizophrenia and healthy controls [51,52]. The e-scale is a questionnaire to assess empathy, consisting of 25 items. ...
Schizophrenia is associated with significant impairments in social cognition. These impairments have been shown to go along with altered activation of the posterior superior temporal sulcus (pSTS). However, studies that investigate connectivity of pSTS during social cognition in schizophrenia are sparse. Twenty-two patients with schizophrenia and 22 matched healthy controls completed a social-cognitive task for functional magnetic resonance imaging that allows the investigation of affective Theory of Mind (ToM), emotion recognition and the processing of neutral facial expressions. Moreover, a resting-state measurement was taken. Patients with schizophrenia performed worse in the social-cognitive task (main effect of group). In addition, a group by social-cognitive processing interaction was revealed for activity, as well as for connectivity during the social-cognitive task, i.e., patients with schizophrenia showed hyperactivity of right pSTS during neutral face processing, but hypoactivity during emotion recognition and affective ToM. In addition, hypoconnectivity between right and left pSTS was revealed for affective ToM, but not for neutral face processing or emotion recognition. No group differences in connectivity from right to left pSTS occurred during resting state. This pattern of aberrant activity and connectivity of the right pSTS during social cognition might form the basis of false-positive perceptions of emotions and intentions and could contribute to the emergence and sustainment of delusions.
... To our knowledge, no study so far specifically investigated the relationship between the Reading the Mind in the Eyes Test and the severity of hallucinations in patients with schizophrenia. However, previous studies did not find associations between the general positive symptom cluster and this test (Csukly et al., 2014;Hirao et al., 2008; but see Guastella et al., 2013), which may point to a symptom specific association between affective ToM and hallucinatory behavior. ...
Social cognitive impairments may represent a core feature of schizophrenia and above all are a strong predictor of positive psychotic symptoms. Previous studies could show that reduced inhibitory top-down control contributes to deficits in theory of mind abilities and is involved in the genesis of hallucinations. The current study aimed to investigate the relationship between auditory inhibition, affective theory of mind and the experience of hallucinations in patients with schizophrenia. In the present study, 20 in-patients with schizophrenia and 20 healthy controls completed a social cognition task (the Reading the Mind in the Eyes Test) and an inhibitory top-down Dichotic Listening Test. Schizophrenia patients with greater severity of hallucinations showed impaired affective theory of mind as well as impaired inhibitory top-down control. More dysfunctional top-down inhibition was associated with poorer affective theory of mind performance, and seemed to mediate the association between impairment to affective theory of mind and severity of hallucinations. The findings support the idea of impaired theory of mind as a trait marker of schizophrenia. In addition, dysfunctional top-down inhibition may give rise to hallucinations and may further impair affective theory of mind skills in schizophrenia.
... While Thaler et al. (2013) found a relationship between ToM impairment and history of psychosis, other studies did not (Bora et al., 2005;Lahera et al., 2008). Deficit schizophrenia might potentially be associated with more severe ToM deficits (Csukly et al., 2014). We were not able to explore the effect of these factors on differences between schizophrenia and BP as relevant information was not available in most studies. ...
Objective:
Cognitive dysfunction is a common characteristic of both schizophrenia and bipolar disorder (BP). While these deficits are more severe in schizophrenia, there is a significant overlap between conditions. However, it was hypothesized that social cognitive deficits might be more specific to schizophrenia.
Methods:
We conducted a meta-analysis of studies comparing facial emotion recognition and theory of mind (ToM) abilities in schizophrenia and BP. 26 studies comparing 1301 patients with schizophrenia and 1075 with BP were included.
Results:
Schizophrenia patients significantly underperformed compared with BP patients in both facial emotion recognition (d=0.39) and ToM (d=0.57). Neurocognitive deficits significantly contributed to schizophrenia-BP group differences for ToM. However, between-group differences for social cognition were not statistically more severe than neurocognition.
Conclusion:
Social cognitive impairment is more severe in schizophrenia in comparison to BP. However, between-group differences are modest and are comparable to other neurocognitive differences between schizophrenia and BP. There is significant overlap in social cognitive performance deficits observed in both schizophrenia and BP.
... Cortical volumetric abnormalities in the DLPFC and disruption of the white matter tracts connecting to the DLPFC have also been regarded as a major feature of deficit schizophrenia , which is characterized by the presence of primary and enduring negative symptoms (Fischer et al., 2012; Voineskos et al., 2013). Deficit schizophrenia has been associated with greater impairment in cognitive ability and social cognition (Cohen et al., 2007; Csukly et al., 2014; Volpe et al., 2012). In particular, negative symptoms include an inclination toward stereotyped thinking (Piskulic and Addington, 2011) and are closely related to social functioning (Hunter and Barry, 2012). ...
Schizophrenia is a mental disorder characterized by impairments in diverse thinking and emotional responses, which are related to social perception dysfunction. This fMRI study was designed to investigate a neurobiological basis of social perception deficits of patients with schizophrenia in various social situations of daily life and their relationship with clinical symptoms and social dysfunction.
Seventeen patients and 19 controls underwent functional magnetic resonance imaging, during which participants performed a virtual social perception task, containing an avatar's speech with positive, negative or neutral emotion in a virtual reality space. Participants were asked to determine whether or not the avatar's speech was appropriate to each situation.
The significant group×appropriateness interaction was seen in the left dorsolateral prefrontal cortex (DLPFC), resulting from lower activity in patients in the inappropriate condition, and left DLPFC activity was negatively correlated with the severity of negative symptoms and positively correlated with the level of social functioning. The significant appropriateness×emotion interaction observed in the left superior temporal sulcus (STS) was present in controls, but absent in patients, resulting from the existence and absence of a difference between the inappropriate positive and negative conditions, respectively.
These findings indicate that dysfunction of the DLPFC-STS network may underlie patients' abnormal social perception in various social situations of daily life. Abnormal functioning of this network may contribute to increases of negative symptoms and decreases of social functioning.
Copyright © 2014. Published by Elsevier Inc.
The reading the mind in the eyes test (RMET) – which assesses the theory of mind component of social cognition – is often used to compare social cognition between patients with schizophrenia and healthy controls. There is, however, no systematic review integrating the results of these studies. We identified 198 studies published before July 2020 that administered RMET to patients with schizophrenia or healthy controls from three English-language and two Chinese-language databases. These studies included 41 separate samples of patients with schizophrenia (total n = 1836) and 197 separate samples of healthy controls (total n = 23 675). The pooled RMET score was 19.76 (95% CI 18.91–20.60) in patients and 25.53 (95% CI 25.19–25.87) in controls (z = 12.41, p < 0.001). After excluding small-sample outlier studies, this difference in RMET performance was greater in studies using non-English v. English versions of RMET (Chi [Q] = 8.54, p < 0.001). Meta-regression analyses found a negative association of age with RMET score and a positive association of years of schooling with RMET score in both patients and controls. A secondary meta-analysis using a spline construction of 180 healthy control samples identified a non-monotonic relationship between age and RMET score – RMET scores increased with age before 31 and decreased with age after 31. These results indicate that patients with schizophrenia have substantial deficits in theory of mind compared with healthy controls, supporting the construct validity of RMET as a measure of social cognition. The different results for English versus non-English versions of RMET and the non-monotonic relationship between age and RMET score highlight the importance of the language of administration of RMET and the possibility that the relationship of aging with theory of mind is different from the relationship of aging with other types of cognitive functioning.
Les troubles cognitifs sont fréquents dans la schizophrénie, ils sont globaux, touchant toutes les sphères de la neurocognition et de la cognition sociale. Les antipsychotiques n’ont qu’un effet limité sur ces atteintes qui présentent donc un impact fonctionnel important, entravant l’insertion sociale, académique et professionnelle des personnes vivant avec une schizophrénie. Ces déficits sont également associés à des troubles de la prise de décision en contexte social, ainsi qu’à des anomalies de l’activité cérébrale. Les interventions en remédiation de la cognition sociale offrent une réponse à ces troubles et se sont largement développées au cours des dernières années. La littérature récente s’est intéressée aux facteurs de réponses à la remédiation cognitive. Il apparait que la compréhension des processus cérébraux sous-jacents à son efficacité pourrait permettre une meilleure appréhension de ces facteurs de réponse. Cette thèse s’est donc intéressée aux effets de la remédiation cognitive sur l’activité cérébrale et la prise de décision. Dans une première étude, nous avons effectué une revue de la littérature existante concernant les effets de différents programmes de remédiation : axée sur une compensation ou une restauration des fonctions lésées, sur l’activité cérébrale. Notre seconde étude s’est basée sur la création d’un paradigme expérimental innovant de prise de décision en contexte social afin de caractériser les processus décisionnels dans la schizophrénie, sur le plan comportemental et cérébral. Enfin notre dernière étude s’est intéressée aux effets d’un programme de remédiation de la cognition sociale sur la prise de décision avec l’utilisation de ce même paradigme et l’activité cérébrale en électroencéphalographie.
Background and hypothesis:
Previous studies have suggested links between clinical symptoms and theory of mind (ToM) impairments in schizophrenia spectrum disorders (SSD), but it remains unclear whether some symptoms are more strongly linked to ToM than others.
Study design:
A meta-analysis (Prospero; CRD42021259723) was conducted to quantify and compare the strength of the associations between ToM and the clinical symptoms of SSD (Positive, Negative, Cognitive/Disorganization, Depression/Anxiety, Excitability/Hostility). Studies (N = 130, 137 samples) including people with SSD and reporting a correlation between clinical symptoms and ToM were retrieved from Pubmed, PsycNet, Embase, Cochrane Library, Science Direct, Proquest, WorldCat, and Open Gray. Correlations for each dimension and each symptom were entered into a random-effect model using a Fisher's r-to-z transformation and were compared using focused-tests. Publication bias was assessed with the Rosenthal failsafe and by inspecting the funnel plot and the standardized residual histogram.
Study results:
The Cognitive/Disorganization (Zr = 0.28) and Negative (Zr = 0.24) dimensions revealed a small to moderate association with ToM, which was significantly stronger than the other dimensions. Within the Cognitive/Disorganization dimension, Difficulty in abstract thinking (Zr = 0.36) and Conceptual disorganization (Zr = 0.39) showed the strongest associations with ToM. The association with the Positive dimension (Zr = 0.16) was small and significantly stronger than the relationship with Depression/Anxiety (Zr = 0.09). Stronger associations were observed between ToM and clinical symptoms in younger patients, those with an earlier age at onset of illness and for tasks assessing a combination of different mental states.
Conclusions:
The relationships between Cognitive/Disorganization, Negative symptoms, and ToM should be considered in treating individuals with SSD.
Importance:
Patients with schizophrenia tend to have severe deficits in theory of mind, which may limit their interpretation of others' behaviors and thereby hamper social participation. Commonly used measures of theory of mind assess the ability to understand various social situations (e.g., implied meaning or hinting, faux pas), but these measures do not yield valid, reliable, and gender unbiased results to inform interventions for managing theory-of-mind deficits. We used understanding of implied meaning, which appears to be a unidimensional construct highly correlated with social competence, as a promising starting point to develop a theory-of-mind assessment.
Objective:
To develop a Rasch-calibrated computerized test of implied meaning.
Design:
Cross-sectional design.
Setting:
Psychiatric hospitals and community.
Participants:
344 participants (240 patients with schizophrenia and 104 healthy adults).
Results:
We initially developed 27 items for the Computerized Implied Meaning Test. After inappropriate items (12 misfit items and 1 gender-biased item) were removed, the remaining 14 items showed acceptable model fit to the Rasch model (infit = 0.84-1.16; outfit = 0.65-1.34) and the one-factor model (comparative fit index = .91, standardized root mean square residual = .05, root-mean-square error of approximation = .08). Most patients (81.7%) achieved individual Rasch reliability of ≥.90. Healthy participants performed significantly better on the test than patients with schizophrenia (Cohen's d = 2.5, p < .001).
Conclusions and relevance:
Our preliminary findings suggest that the Computerized Implied Meaning Test may provide reliable, valid, and gender-unbiased results for patients with schizophrenia. What This Article Adds: We developed a new measure for assessing theory-of-mind ability in patients with schizophrenia that consists of items targeting the understanding of implied meaning. Preliminary findings suggest that the Computerized Implied Meaning Test is reliable, valid, and gender unbiased and may be used in evaluating patients' theory-of-mind deficits and relevant factors.
Background:
Patients with deficit syndrome (DS) are known to experience cognitive impairment. However, there is no consistent conclusion on the impairment of neurocognitive features in DS patients, and no studies have examined their empathy. The purpose of this study was to compare neurocognition and empathy in patients with DS and non-DS schizophrenia.
Methods:
Totally, 665 patients with chronic schizophrenia were enrolled. DS patients were identified by the Proxy Scale for Deficit Syndrome (PDS). Neurocognition and social cognition were assessed by Repeatable Battery for the measurement of Neuropsychological Status (RBANS) and the Interpersonal Reactivity Index (IRI), respectively. In addition, psychopathological symptom severity was assessed by the Positive and Negative Syndrome Scale (PANSS).
Results:
Participants included 150 patients with DS and 140 patients with non-DS. DS patients performed significantly worse on the all RBANS domain (except for visuospatial) and total scores as well as IRI scores. Regression analysis showed that PANSS general psychopathology and education were associated with RBANS total score in the DS group (adjusted R2 = 0.29), while education and PANSS negative symptoms were correlated with RBANS total score in non-DS patients (adjusted R2 = 0.33). In the non-DS group, suicide attempts and PANSS negative symptom score were independently associated with IRI total score (adjusted R2 = 0.06), whereas in the DS group, no variable was associated with IRI total score.
Conclusions:
Our findings suggest that patients with DS may have poor neurocognitive and empathy performance. In chronic schizophrenia patients, negative symptoms may play a different role in cognition between DS and non-DS groups.
Background:
Deficit syndrome (DS) is a common subgroup of schizophrenia. However, few studies have examined the prevalence and risk factors for DS in Chinese Han patients with schizophrenia. The aim of this study was to assess prevalence, demographic and clinical characteristics of DS in Chinese Han patients with first-episode drug naïve (FEDN) schizophrenia.
Methods:
In total, 235 patients with schizophrenia were recruited, and clinical and demographic data were collected. The Positive and Negative Syndrome Scale (PANSS) was utilized for the psychopathological symptoms, and the 17-item Hamilton Depression Rating Scale (HDRS-17) for depressive symptoms. The Proxy for the Deficit Syndrome (PDS) was adopted to identify DS.
Results:
The prevalence of DS in the cohort of first-episode schizophrenia patients was 23.0%. Compared to those patients without DS, patients with DS had younger age, lower education level, and were more likely to be single. Further, DS patients had significantly lower scores of positive symptoms, general psychopathology, and depression than non-DS patients. Patients with DS had fewer suicide attempts, but they had more severe negative symptoms and cognitive impairment (all p < 0.05). Multiple regression showed that poor cognitive functioning, lower levels of depression and younger age at onset were predictors of DS.
Conclusions:
Chinese Han patients with FEDN schizophrenia have high prevalence of DS. Some demographic and clinical parameters may be associated with DS.
The ability to mentalize, or theory of mind (ToM), is sexually dimorphic in humans and impaired in schizophrenia. This sex-stratified study probed cognitive (indexed by intelligence) and affective (indexed by olfactory tasks) contributions to ToM performance in 37 individuals with schizophrenia and 31 healthy controls. The schizophrenia group showed impairments in mental state identification and inferring intentions compared to controls. Higher intelligence was correlated with mental state identification and inferring intentions in healthy females, whereas better smell identification was associated with mental state identification in healthy males. Conversely, higher intelligence was associated with mental state identification and inferring intentions in schizophrenia males, while better smell identification was correlated with mental state identification in schizophrenia females. These findings suggest that for ToM circuitry, the cognitive influences in healthy females and affective influences in healthy males are reversed in schizophrenia and may be displaced to lower circuitries by disease pathology. Symptom associations with emotion and cognition are also dimorphic, plausibly due to similar pathology superimposed on normal sex-specific circuitries. Males appear to rely on limbic processing for ToM, and disruption to this circuitry may contribute to development of negative symptoms. These findings highlight the importance of utilizing sex-stratified designs in schizophrenia research.
Objectives: Although it has been shown that there are more profound deficits present in deficit schizophrenia (DS) patients than in non-deficit schizophrenia (NDS) patients, there still remain some matters requiring further investigation. In this context, we formulated three research aims: (1) to compare executive functions between the investigated groups, (2) to determine the relationship between particular aspects of executive functions within the groups, and (3) to draw up a neuropsychological profile for executive functions.
Methods: The study involved 148 schizophrenia patients divided into two groups on the basis of the Schedule for the Deficit Syndrome: DS (n = 70) and NDS (n = 78). Patients were matched for sex, age, years of education, and overall cognitive functioning. For assessing executive functions we used the Wisconsin Card Sorting Test (WCST), the Trail Making Test (TMT), the Phonemic Verbal Fluency Test (VFT P), the Stroop Color and Word Test (SCWT), and the Go/No Go task (GNG).
Results: Deficit schizophrenia patients scored lower on the WCST and TMT (relative flexibility) than did the NDS patients. There were no inter-group differences in the VFT P, SCWT (relative inhibition), or GNG. There were significant correlations between WCST and TMT scores in both groups. The general neuropsychological profiles were similar in both groups.
Conclusion: Deficit schizophrenia patients exhibited slightly greater interference with concept formation and non-verbal cognitive flexibility. Therefore, such problems may be specific to this particular type of schizophrenia. These results may be useful for the development of neuropsychological diagnostic methods for patients with schizophrenia.
Teoría de la mente y esquizofrenia: una revisión de la literatura disponible en los últimos cinco años (2010-2014) Noelia NAVARRO GÓMEZ Universidad de Almería Resumen La Teoría de la Mente (ToM), conceptuada como la habilidad de atribuir creencias, intenciones o emociones a uno mismo o a otros y ver estos estados mentales como la base de las acciones, así como las implicaciones de su afectación en la cognición social, se han puesto de relevancia en los últimos años en el ámbito de la esquizofrenia. Se presenta una revisión teórica de la literatura disponible publicada en los últimos cinco años (2010-2014). Se observa el predominio del modelo biomédico, interesado en encontrar las relaciones entre los déficits en habilidades de ToM y estructuras cerebrales. En líneas generales, puede concluirse que las habilidades de ToM, constituyen una variable predictora del funcionamiento social y global, pudiendodar cuenta de la pobre comprensión del sarcasmo, el lenguaje figurativo y el humor en pacientes con esquizofrenia. Se determina la necesidad de establecer nuevos paradigmas, de corte interactivo y validez ecológica, superando las limitaciones de las medidas tradicionalmente utilizadas para evaluar la ToM, siendo fundamental la continuidad y el desarrollo de líneas de intervención. Palabras clave: teoría de la mente, esquizofrenia, cognición social, revisión. Abstract The Theory of Mind (ToM), conceptualized as the ability to attribute beliefs, intentions or emotions to oneself or others and understand these mental states as the basis of actions, and the implications of their involvement in social cognition, have been of importance in recent years in the field of schizophrenia. A theoretical review of the literature published in the last five years (2010-2014) is presented. The dominance of biomedical model is observed, interested in finding the relationship between deficits in ToM skills and brain structures. In general, it can be concluded that ToM skills, constitute a predictor of social and global functioning, and may account for the understanding of sarcasm, figurative language and mood in patients with schizophrenia. The need of new paradigms, of interactive orientation and ecological validity is determined, overcoming the limitations of traditional measures used to assess ToM. Continuity and development of lines of intervention are crucial. La Teoría de la Mente (ToM, por sus siglas en inglés) (Premack y Woodruff, 1978) y las implicaciones de su afec-tación en la cognición social se han puesto de relevancia en los últimos años en el ámbito de la esquizofrenia. Tradicio-nalmente, se define la ToM como la habilidad de atribuir creencias, intenciones o emociones a uno mismo o a otros y ver estos estados mentales como la base de las acciones (Bosacki, 2000) lo que posibilita adoptar la perspectiva de otros o de uno mismo en diferentes situaciones (de tiempo o lugar). La ToM constituiría una de las denominadas habili-dades prerrequisitas en cualquier interacción, dado su papel en la comprensión, explicación, predicción y manipulación de la conducta de otros (Yirmiya, Erel, Shaked y Solomo-nica-Levi,1998) favoreciendo de este modo el autocontrol, el autoconocimiento y cualquier tipo de interacción social (Zelazo, Burack, Benedetto y Frye, 1996). Desde un enfoque cognitivo, o neurocognitivo, que constituye la aproximación principal al concepto, la Teoría de la Mente y su origen es un producto cronológico de la edad y el desarrollo biológico. Aunque inicialmente comenzó a estudiarse en el campo del
Background:
Most studies suggested that patients with deficit schizophrenia have more severe impairment compared with patients with non-deficit schizophrenia. However, it is not clear whether deficit and non-deficit schizophrenia are associated with differential neurocognitive profiles.
Methods:
The aim of this meta-analytic review was to compare cognitive performances of deficit and non-deficit patients with each other and with healthy controls. In the current meta-analysis, differences in cognitive abilities between 897 deficit and 1636 non-deficit patients with schizophrenia were examined. Cognitive performances of 899 healthy controls were also compared with 350 patients with deficit and 592 non-deficit schizophrenia.
Results:
Both deficit (d = 1.04-1.53) and non-deficit (d = 0.68-1.19) schizophrenia were associated with significant deficits in all cognitive domains. Deficit patients underperformed non-deficit patients in all cognitive domains (d = 0.24-0.84) and individual tasks (d = 0.39-0.93). The relationship between deficit syndrome and impairment in olfaction, social cognition, verbal fluency, and speed-based cognitive tasks were relatively stronger.
Conclusions:
Our findings suggest that there is consistent evidence for a significant relationship between deficit syndrome and more severe cognitive impairment in schizophrenia.
Schizophrenia is a heterogeneous disorder characterized by numerous diverse signs and symptoms. Individuals with prominent, persistent, and idiopathic negative symptoms are thought to encompass a distinct subtype of schizophrenia. Previous work, including studies involving neuropsychological evaluations, has supported this position. The present study sought to further examine whether deficit patients are cognitively distinct from non-deficit patients with schizophrenia. A comprehensive neurocognitive battery including tests of verbal memory, vigilance, processing speed, reasoning, and working memory was administered to 657 patients with schizophrenia. Of these, 144 (22 %) patients were classified as deficit patients using a proxy identification method based on severity, persistence over time, and possible secondary sources (e.g., depression) of negative symptoms. Deficit patients with schizophrenia performed worse on all tests of cognition relative to non-deficit patients. These patients were characterized by a generalized cognitive impairment on the order of about 0.4 standard deviations below that of non-deficit patients. However, when comparing deficit patients to non-deficit patients who also present with negative symptoms, albeit not enduring or primary, no group differences in cognitive performance were found. Furthermore, a discriminant function analysis classifying patients into deficit/non-deficit groups based on cognitive scores demonstrated only 62.3 % accuracy, meaning over one-third of individuals were misclassified. The deficit subtype of schizophrenia is not markedly distinct from non-deficit schizophrenia in terms of neurocognitive performance. While deficit patients tend to have poorer performance on cognitive tests, the magnitude of this effect is relatively modest, translating to over 70 % overlap in scores between groups.
Although first-episode drug naive patients with schizophrenia are known to show cognitive impairment, the cognitive performances of these patients, who suffer deficit syndrome, compared with those who suffer non-deficit syndrome is undetermined. The aim of this study was to compare cognitive performances in first-episode drug-naive schizophrenia with deficit syndrome or non-deficit syndrome. First-episode drug naive patients (n=49) and medicated patients (n=108) with schizophrenia, and age, sex, and education matched healthy controls (n=57 for the first-episode group, and n=128 for the medicated group) were enrolled. Patients were divided into deficit or non-deficit syndrome groups, using the Schedule for Deficit Syndrome. Cognitive performance was assessed using the CogState computerized cognitive battery. All cognitive domains in first-episode drug naive and medicated patients showed significant impairment compared with their respective control groups. Furthermore, cognitive performance in first-episode drug naive patients was significantly worse than in medicated patients. Interestingly, the cognitive performance markers of processing speed and attention, in first-episode drug naive patients with deficit syndrome, were both significantly worse than in equivalent patients without deficit syndrome. In contrast, no differences in cognitive performance were found between the two groups of medicated patients. In conclusion, this study found that first-episode drug naive schizophrenia with deficit syndrome showed significantly impaired processing speed and attention, compared with patients with non-deficit syndrome. These findings highlight processing speed and attention as potential targets for pharmacological and psychosocial interventions in first-episode schizophrenia with deficit syndrome, since these domains are associated with social outcomes.
While second-generation antipsychotics treat negative as well as positive symptoms, recovery for persons with schizophrenia remains elusive, in part because there are no FDA-approved medications that treat the cognitive deficits of schizophrenia (CDS). Recent work has identified agents that, when added to antipsychotics, improve cognition in schizophrenia. This work and hypothesized mechanisms of action will be reviewed.
An individual has a theory of mind if he imputes mental states to himself and others. A system of inferences of this kind is properly viewed as a theory because such states are not directly observable, and the system can be used to make predictions about the behavior of others. As to the mental states the chimpanzee may infer, consider those inferred by our own species, for example, purpose or intention, as well as knowledge, belief, thinking, doubt, guessing, pretending, liking, and so forth. To determine whether or not the chimpanzee infers states of this kind, we showed an adult chimpanzee a series of videotaped scenes of a human actor struggling with a variety of problems. Some problems were simple, involving inaccessible food – bananas vertically or horizontally out of reach, behind a box, and so forth – as in the original Kohler problems; others were more complex, involving an actor unable to extricate himself from a locked cage, shivering because of a malfunctioning heater, or unable to play a phonograph because it was unplugged. With each videotape the chimpanzee was given several photographs, one a solution to the problem, such as a stick for the inaccessible bananas, a key for the locked up actor, a lit wick for the malfunctioning heater. The chimpanzee's consistent choice of the correct photographs can be understood by assuming that the animal recognized the videotape as representing a problem, understood the actor's purpose, and chose alternatives compatible with that purpose.
Aim:
Currently substantial evidence exists about Theory of Mind (ToM) impairment in subjects affected by chronic and first episode schizophrenia. In particular, in order to enhance the validity of our construct, we used in this study classical false beliefs tasks and advanced theory of mind tasks, together with the application of structural equation model, in order to ex-amine whether we are using ToM tasks with good psychometric properties. The main goal of the present study was to examine ToM deficits in a large sample including subjects suffering from chronic schizophrenia, first episode of schizophrenia and nor-mal controls, by observing in the same task the relationship with symptomatological gravity, neurocognition and social function.Materials and methods. A sample of 178 patients with chronic schizophrenia, a sample of 49 subjects with a first episode of psychosis and 484 healthy controls participated to this study. Measures of social cognition included task of false belief and advanced theory of mind task.
Results:
No significant differences were found on ToM tasks between subjects affected by chronic and first episode schizophrenia. Social cognition showed in both groups a strong correlation with negative symptoms and social function, but did not evidence any relationship with neurocognition. CONCLUSION; ToM deficits exist in subjects suffering from chronic and first episode schizophrenia. These impairments do not seem to be a consequence of illness condition, they are likely to be state-independent and appear to be the most important cognitive mediator of social functioning in both groups.
How to improve treatment for negative symptoms is a continuing topic of debate. Suggestions have been made to advance psychological understanding of negative symptoms by focusing on the social cognitive processes involved in symptom formation and maintenance.
Following the recommendations by the National Institute of Mental Health workshop on social cognition in schizophrenia, this study investigated associations between negative symptoms and various aspects of social cognition including Theory of Mind (ToM), attribution, empathy, self-esteem, and interpersonal self-concepts in 75 patients with schizophrenia spectrum disorders and 75 healthy controls.
Negative symptoms were significantly associated with difficulties in ToM, less readiness to be empathic, lower self-esteem, less self-serving bias, negative self-concepts related to interpersonal abilities, and dysfunctional acceptance beliefs. Different aspects of social cognition were mildly to moderately correlated and interacted in their impact on negative symptoms: Difficulties in ToM were associated with negative symptoms in persons with low but not in persons with medium or high levels of self-esteem. Taken together, the social cognition variables and their hypothesized interaction explained 39% of the variance in negative symptoms after controlling for neurocognition and depression.
The results highlight the relevance of self-concepts related to social abilities, dysfunctional beliefs, and global self-worth alone and in interaction with ToM deficits for negative symptoms and thereby provide a helpful basis for advancing psychosocial interventions.
In motion perception, there are a number of important phenomena involving coherence. Examples include motion capture and motion cooperativity. We propose a theoretical model, called the motion coherence theory, that gives a possible explanation for these effects [1,2]. In this framework, the aperture problem can also be thought of as a problem of coherence and given a similar explanation. We propose the concept of a velocity field defined everywhere in the image, even where there is no explicit motion information available. Theough a cost function, the model imposes smoothness on the velocity field in a more general way than in previous theories. In this paper, we provide a detailed theoretical analysis of the motion coherence theory. We discuss its relations with previous theories and show that some of them are approximations to it. A second paper [3] provides extensions for temporal coherence and comparisons to psychophysical phenomena. The theory applies to both short-range and long-range motion. It places them in the same computational framework and provides a way to define interactions between the two processes.
Although there is some evidence that Theory of Mind (ToM) deficits may be trait markers of schizophrenia it is not clear yet if ToM deficits are primary deficits, that is, to be independent of deficits in general intellectual abilities and executive function. The aim was to examine if ToM deficits may be trait markers of the illness and the effect of cognitive inhibition, general intellectual abilities and depression on ToM abilities of patients with schizophrenia and their unaffected parents.
We assessed ToM abilities (first-order and second-order ToM stories, The Revised Eyes Test), cognitive inhibition (Stroop Task), general intellectual ability (Standard Progressive Matrices Test Plus) in patients with schizophrenia (N=21) and their unaffected fathers (N=21) and mothers (N=21) in comparison with healthy control families (healthy control males, N=21, healthy control fathers, N=21, healthy control mothers, N=21)
Patients showed deficits in first-order ToM tasks but some of these deficits were mediated by general intellectual abilities. Impairments in cognitive inhibition mediated only patients' performance in The Revised Eyes Test. Patients showed deficits in second-order ToM stories independently of deficits in general intellectual abilities and cognitive inhibition. Unaffected parents did not show deficits in first-order ToM tasks, whereas they showed deficits in second-order ToM stories. However, the deficits that unaffected parents showed in second-order ToM stories were mediated by their deficits in general intellectual abilities, and there was an effect of remitted depression on the unaffected mothers' performance.
The results suggest that intact neurocognitive and general intellectual abilities are necessary in order patients and their unaffected parents to pass successfully ToM tasks. Patients and their unaffected parents show ToM deficits but these deficits are not similar. Patients show ToM deficits but these deficits seem to be a component of the pathophysiology of the illness (e.g., deficits in executive function, general intellectual abilities).
This study aimed to use data mining to explore the significantly contributing variables to good social functioning in schizophrenia patients.
The study cohort comprised 67 schizophrenia patients on stable medication. A total of 51 variables (6 demographic data, 3 illness history, 22 social cognition, 16 neurocognition, 4 psychiatric symptoms) were input into a data-mining decision tree using the Answer Tree program to find the pathway for the best social functioning.
Several contributing factors for good social functioning were found. Continuous attention was the strongest contributing factor. Three variables involving best social functioning included good continuous attention, good theory of mind (TOM), and low sensitivity of disgust emotion.
Our results confirmed the mediating roles of social cognition between neurocognition and functional outcomes, and suggested that social cognition can significantly predict social functioning in schizophrenia patients.
Facial emotion recognition deficits have been widely investigated in individuals with schizophrenia; however, it remains unclear whether these deficits reflect a trait-like vulnerability to schizophrenia pathology present in individuals at risk for the disorder. Although some studies have investigated emotion recognition in this population, findings have been mixed. The current study uses a well-validated emotion recognition task, a relatively large sample, and examines the relationship between emotion recognition, symptoms, and overall life quality. Eighty-nine individuals with psychometrically defined schizotypy and 27 controls completed the Schizotypal Personality Questionnaire, Penn Emotion Recognition Test, and a brief version of Lehman's Quality of Life Interview. In addition to labeling facial emotions, participants rated the valence of faces using a Likert rating scale. Individuals with schizotypy were significantly less accurate than controls when labeling emotional faces, particularly neutral faces. Within the schizotypy sample, both disorganization symptoms and lower quality of life were associated with a bias toward perceiving facial expressions as more negative. Our results support previous research suggesting that poor emotion recognition is associated with vulnerability to psychosis. Although emotion recognition appears unrelated to symptoms, it probably operates by means of different processes in those with particular types of symptoms.
Although cognition has been studied extensively among patients with schizophrenia, social cognition has only recently emerged as an area of interest. The objective of the current study was to use structural equation modelling to test the hypothesis that the relation between cognitive performance and social function is mediated by patients' social cognitive abilities.
We assessed participants who met criteria for a schizophrenia-spectrum disorder, with equal distribution among first- and multi-episode participants, and nonpsychiatric controls on a range of measures within each of the domains of cognition, social cognition and social function.
Using structural equation modelling, we derived a model that explained 79.7% of the variance in social function and demonstrated that the link between cognition and social function was fully mediated by social cognition.
A limitation of this study is that the measures contributing to the structural equation modelling analysis were obtained at the same point in time. Thus, the temporal order of causation suggested by Model 2 remains theoretically specified.
This study provides some first steps in understanding the complex relation between cognition and social function. Such a relation has potential implications for the design of remediation strategies.
Tasks measuring reasoning biases and social cognition were originally applied to the study of schizophrenia in order to shed light on the cognitive underpinnings of positive symptoms. However, the empirical evidence for overlap between these tasks, and their association with positive symptoms, remains preliminary. In the current study we explore these associations using multivariate methodology, with primary interest in two commonly studied paradigms: jumping to conclusions (JTC) and theory of mind (ToM). We also included measures of memory, executive function and fluency performance, in order to relate the cognitive constructs to more traditional neuropsychological constructs. Forty-six schizophrenia inpatients were administered JTC, ToM, verbal fluency, executive functioning, and verbal memory tasks. A principal component analysis resulted in three components interpreted as Memory, Elaboration and Flexibility. ToM loaded with verbal fluency on the Elaboration component, whereas JTC loaded with executive functioning on the Flexibility component. The negative susbscale of the Positive and Negative Syndrome Scale (PANSS) correlated with the Elaboration component, but no other component-subscale correlations reached significance. Implications of these results are that impairments in elaboration may underlie the commonly observed correlation between ToM and negative symptoms, but argue against a common neurocognitive system for JTC, ToM and positive symptoms.
If schizophrenia is a clinical syndrome rather than a single disease, the identification of specific diseases within the syndrome would facilitate the advance of knowledge and the development of more specific treatments. We propose that deficit psychopathology (ie, enduring, idiopathic negative symptoms) defines a group of patients with a disease different from schizophrenia without deficit features, as the deficit and nondeficit groups differ in their signs and symptoms, course, biological correlates, treatment response, and etiologic factors. These differences cannot be attributed to more severe positive psychotic symptoms or a greater duration of illness in the deficit group. The alternative interpretation that patients with deficit schizophrenia are at the severe end of a single disease continuum is not supported by risk factor and biological features data, but there is a need for independent replication of these findings. We suggest a series of studies designed to falsify one of these hypotheses, ie, multiple diseases vs a single disease.
Gender effects have been reported quite consistently in schizophrenia, with male patients having an earlier age of onset, poorer functional outcome, greater negative symptoms and cognitive impairment, and less severe positive symptoms. Because age of onset, cognitive impairments, and negative symptoms are all correlated with poorer functional status, it is not clear if previously reported gender differences in symptoms are just recapturing gender differences in functional outcome. In this study, 205 geriatric patients with lifelong poor-outcome schizophrenia (43% male) were examined for the severity of schizophrenic symptoms, cognitive impairments, and specific deficits in adaptive skills, as well as for demographic differences such as age at first psychiatric admission, premorbid education, and current treatment status. Previously reported gender differences were replicated in these patients with a uniformly poor functional outcome, with male patients having more severe negative symptoms and an earlier age of first psychiatric admission. No differences in cognitive functioning or specific functional deficits were found, however. These findings suggest that negative symptom severity is greater in male patients regardless of functional outcome and that the association of cognitive deficits with gender may be found only in patients with better functional outcome. The study of gender-related differences in brain structure or function and their interaction with overall course of illness might help understand these differences in symptom presentation.
The term theory of mind (ToM) refers to the capacity to infer one's own and other persons' mental states. A substan-tial body of research has high-lighted the evolution of ToM in nonhuman primates, its emergence during human ontog-eny, and impaired ToM in a variety of neuropsychiatric dis-orders, including schizophrenia. There is good empirical evidence that ToM is specifically impaired in schizophrenia and that many psychotic symptoms - for instance, delusions of alien control and persecution, the presence of thought and language disorganization, and other behavioral symp-toms - may best be understood in light of a disturbed capac-ity in patients to relate their own intentions to executing behavior, and to monitor others' intentions. However, it is still under debate how an impaired ToM in schizophrenia is associated with other aspects of cognition, how the impair-mentfluctuates with acuity or chronicity of the schizophrenic disorder, and how this affects the patients' use of language and social behavior. In addition to these potential research areas, future studies may also address whether patients could benefit from cognitive training in this domain.
Theory of mind (ToM) deficit is a well-established feature of schizophrenia and has been suggested as a vulnerability marker of this disorder. However, as most of this evidence is based on studies in chronic patients, it is less clear whether ToM is impaired prior to or following the onset of a first-episode and whether it is evident in unaffected relatives of patients. In this meta-analysis, ToM performance of 3005 individuals with first-episode psychosis (FEP), individuals at ultra-high risk for psychosis (UHR) and unaffected relatives were compared with 1351 healthy controls. ToM was substantially impaired in first-episode psychosis (Cohen d=1.0) and this deficit was comparable to findings in chronic patients. ToM was also impaired in unaffected relatives (d=0.37) and UHR subjects (d=0.45) and performances of these groups were intermediate between FES and healthy controls. Severity of ToM deficits in unaffected relatives and UHR subjects was similar to other cognitive deficits observed in these groups. Longitudinal studies of clinical and genetic high-risk subjects are necessary to investigate the trajectory of development of ToM deficits in schizophrenia.
BACKGROUND: Social cognition has been identified as a significant construct for schizophrenia research with relevance to diagnosis, assessment, treatment and functional outcome. However, social cognition has not been clearly understood in terms of its relationships with neurocognition and functional outcomes. The present study sought to examine the empirical independence of social cognition and neurocognition; to investigate the possible causal structure among social cognition, neurocognition and psychosocial functioning.Method
The sample consists of 130 individuals diagnosed with schizophrenia. All participants were recruited as they were admitted to four community-based psychosocial rehabilitation programs. Social cognition, neurocognition and psychosocial functioning were measured at baseline and 12 months. The empirical independence of social cognition and neurocognition was tested using confirmatory factor analysis (CFA) and the possible causal structure among social cognition, neurocognition and psychosocial functioning was investigated using latent difference score (LDS) analysis. RESULTS: A two-factor model of social cognition and neurocognition fit the data very well, indicating the empirical independence of social cognition, whereas the longitudinal CFA results show that the empirical independence of neurocognition and social cognition is maintained over time. The results of the LDS analysis support a causal model that indicates that neurocognition underlies and is causally primary to social cognition, and that neurocognition and social cognition are causally primary to functional outcome. CONCLUSIONS: Social cognition and neurocognition could have independent and distinct upward causal effects on functional outcome. It is also suggested that the approaches for remediation of neurocognition and social cognition might need to be distinct.
Social cognitive impairments are considered to be core features of schizophrenia and have been hypothesized to play a mediator role between basic neurocognition and patients' outcomes. In this context, theory of mind (ToM) abilities are of special relevance, and deficits in this area may represent trait markers of schizophrenia.
In this review, studies published since September 2010 have been summarized with a particular focus on the relationships between ToM and psychopathology, neurocognition, and psychosocial outcomes in patients with schizophrenia, as well as on ToM abilities in high-risk individuals. In addition, recent neuroimaging data as well as treatment interventions have been described.
The reviewed literature strengthens the hypothesis that ToM deficits have the potential to be valid markers for schizophrenia.
Social cognitive impairment in schizophrenia is common and associated with poor functional outcome. While correlations in the moderate range suggest that social cognition and neurocognition are separate but overlapping domains, less is known about whether intact neurocognition represents a "necessary but not sufficient" condition for intact social cognition, as has been suggested. In the present study we examined the following in a sample of 119 psychiatrically stable outpatients with schizophrenia: 1) correlations between multiple social cognitive measures and neurocognition, 2) the predictive value of neurocognitive domains in explaining social cognitive performance, and 3) the co-occurrence of social cognitive and neurocognitive impairment within participants. While ¼ of participants showed intact overall neurocognition and impaired overall social cognition, only one participant had normal-range social cognition and impaired neurocognition. Results support the notion that normal range neurocognition is a necessary though not necessarily sufficient building block for good social cognitive performance.
Earlier studies suggested more severe overall cognitive impairments in deficit versus non-deficit schizophrenia; however, the specific contribution of different cognitive domains to this overall cognitive impairment remains unclear. The purpose of this study was to compare the two subtypes in general cognitive functioning as well as in individual cognitive domains using the composite score approach. One hundred and forty-three patients fulfilling the criteria for the deficit syndrome were compared with 123 patients diagnosed with non-deficit schizophrenia. Neurocognitive functioning was assessed by a neuropsychological test battery measuring the domains of sustained vigilance/attention, working memory, short-term memory, verbal memory, cognitive flexibility, and ideation fluency. Using the raw neuropsychological measures, we calculated a global index of cognitive impairment and domain-specific composite z-scores. Association between these composite scores and the deficit syndrome was examined by logistic regression analysis. After adjusting for relevant covariates including sex, age, education, smoking, and antipsychotic dose, results indicated a significant increase in the likelihood of deficit syndrome as a function of global (OR = 5.40; 95% CI 3.02-9.65) as well as domain-specific impairments (OR > 2 for all individual domains except for short-term memory). Cognitive flexibility was an independent predictor (OR = 2.92; 95% CI 1.47-5.80), whereas other cognitive domains demonstrated no unique contribution to the general cognitive impairment. Patients with deficit schizophrenia suffer from a more severe degree of neurocognitive impairment, which is qualitatively similar to the dysfunction seen in non-deficit schizophrenia. However, our results indicate that cognitive flexibility is specifically impaired in deficit versus non-deficit patients and may therefore represent a core feature of this subtype.
Social cognitive impairments are common, detectable across a wide range of tasks, and appear to play a key role in explaining poor outcome in schizophrenia and related psychotic disorders. However, little is known about the underlying factor structure of social cognition in people with psychotic disorders due to a lack of exploratory factor analyses using a relatively comprehensive social cognitive assessment battery. In a sample of 85 outpatients with psychosis, we examined the factor structure and clinical/functional correlates of eight indexes derived from five social cognition tasks that span the domains of emotional processing, social perception, attributional style, and Theory of Mind. Exploratory factor analysis revealed three factors with relatively low inter-correlations that explained a total of 54% of the variance: (1) Hostile attributional style, (2) Lower-level social cue detection, and (3) Higher-level inferential and regulatory processes. None of the factors showed significant correlations with negative symptoms. Factor 1 significantly correlated with clinical symptoms (positive, depression-anxiety, agitation) but not functional outcome, whereas Factors 2 and 3 significantly correlated with functional outcome (functional capacity and real-world social and work functioning) but not clinical symptoms. Furthermore, Factor 2 accounted for unique incremental variance in functional capacity, above and beyond non-social neurocognition (measured with MATRICS Consensus Cognitive Battery) and negative symptoms. Results suggest that multiple separable dimensions of social cognition can be identified in psychosis, and these factors show distinct patterns of correlation with clinical features and functional outcome.
Problems in real-world functioning are pervasive in schizophrenia and much recent effort has been devoted to uncovering factors which contribute to poor functioning. The goal of this study was to examine the role of four such factors: social cognition (theory of mind), neurocognition, negative symptoms, and functional capacity (social competence). 178 individuals with schizophrenia or schizoaffective disorder completed measures of theory of mind, neurocognition, negative symptoms, social competence, and self-reported functioning. Path models sought to determine the relationships among these variables. Theory of mind as indexed by the Hinting Task partially mediated the relationship between neurocognition and social competence, and negative symptoms and social competence demonstrated significant direct paths with self-reported functioning. Study results suggest theory of mind serves as an important mediator in addition to previously investigated social cognitive domains of emotional and social perception. The current study also highlights the need to determine variables which mediate the relationship between functional capacity and real-world functioning.
Neuropsychological characterization of the schizophrenia deficit syndrome is an unresolved issue. The initial assumption was that patients with deficit syndrome show more definitive impairments on tests sensitive for frontal and parietal functions compared with nondeficit patients,but recent studies failed to confirm this assumption. The fundamental question is whether a more refined delineation of executive dysfunctions is able to yield differences between deficit and nondeficit patients. To investigate this question, we implemented a factor analytic approach to explore potential differences between deficit and nondeficit patients using the Wisconsin Card Sorting Test (WCST). Our paper presents an exploratory factor analysis of the WCST on schizophrenia patients and healthy samples, and a comparison among deficit, non-deficit patients with schizophrenia and control samples using the identified factors. A total of 154 patients with schizophrenia fulfilling the criteria for the deficit syndrome, 121 nondeficit patients, and 130 healthy controls were compared. Factor analysis of the WCST variables using the principal component method resulted in a two-factor solution. Comparison of the diagnostic groups on each of the factors revealed that deficit schizophrenia patients suffer from a more severe degree of impairment on the 'General executive function' factor than nondeficit schizophrenia patients. To our knowledge this is the first study that compared patients with the deficit and non-deficit forms of schizophrenia using WCST factor analytic techniques. Our results provide an insight into the cognitive profile of schizophrenia patients with regard to WCST, which could serve as a framework for future clinical and research endeavors.
The current systematic review and meta-analysis provides an extended and comprehensive overview of the associations between neurocognitive and social cognitive functioning and different types of functional outcome. Literature searches were conducted in MEDLINE and PsycINFO and reference lists from identified articles to retrieve relevant studies on cross-sectional associations between neurocognition, social cognition and functional outcome in individuals with non-affective psychosis. Of 285 studies identified, 52 studies comprising 2692 subjects met all inclusion criteria. Pearson correlations between cognition and outcome, demographic data, sample sizes and potential moderator variables were extracted. Forty-eight independent meta-analyses, on associations between 12 a priori identified neurocognitive and social cognitive domains and 4 domains of functional outcome yielded a number of 25 significant mean correlations. Overall, social cognition was more strongly associated with community functioning than neurocognition, with the strongest associations being between theory of mind and functional outcomes. However, as three-quarters of variance in outcome were left unexplained, cognitive remediation approaches need to be combined with therapies targeting other factors impacting on outcome.
This study was designed to clarify the consecutive temporal mechanisms and gender effects underlying facial affect processing in patients with schizophrenia and normal controls through electrophysiological measurements. The following four event-related potential (ERP) components were chosen as indexes of four distinct stages: P100, N170, N250, and P300. A total of 38 schizophrenia patients (22 females) and 38 normal controls (20 females) were recruited. ERPs were recorded while participants identified emotions in images of faces showing three different states: happy, fearful and neutral. The mean peak amplitude of N170 was significantly lower in schizophrenia patients than in normal controls. The mean peak amplitudes of N170 and N250 for fearful emotion were significantly higher than that for happy emotion. The latencies of N170, and P300 were longer in schizophrenia patients than in normal controls. Gender effects were found for P100 peak amplitude and N170 latency, and significant interactions with gender were found for P300 amplitudes and P100 latency. Our results provide evidences of the dysfunctional ERP patterns underlying facial affect processing in schizophrenia patients. Furthermore, the results suggest that gender could be an important controlling factor for facial affect processing in schizophrenia patients.
Social and affective disturbances have long been thought to be core to schizophrenia. Deficits in accurately identifying and discriminating facial displays of emotion may be central components of the functional and social abnormalities seen in schizophrenia; however, their relationship with negative symptoms is less clear. The current study examined facial affect labeling and discrimination performance in a sample of 15 patients meeting criteria for deficit syndrome schizophrenia, 26 schizophrenia patients who do not meet criteria for the deficit syndrome, and 22 healthy controls. Results indicated that deficit schizophrenia patients displayed significantly greater facial affect labeling and discrimination difficulties than non-deficit patients and controls, as well as poorer performance on a basic visuoperceptual face processing task, suggesting that problems with facial affect processing may be mediated by a more general impairment in visuoperceptual processing. However, within this more generalized pattern of impairment, deficit syndrome patients were uniquely characterized by processing positive faces less accurately than negative faces. These findings suggest that abnormalities in processing facial emotion are associated with the negative symptoms of schizophrenia, with a unique deficit in the processing of positive emotions that stand out in the broader context of generalized impairment.
Genetic association studies have yielded extensive but frequently inconclusive data about genetic risk factors for schizophrenia. Clinical and genetic heterogeneity are possible factors explaining the inconsistent findings. The objective of this study was to test the association of commonly incriminated candidate genes with two clinically divergent subgroups, non-deficit (SZ-ND) and deficit-schizophrenia (SZ-D), and symptom severity, in order to test for replication of previously reported results. A homogeneous sample of 280 schizophrenia patients and 230 healthy controls of Hungarian, Caucasian descent were genotyped for polymorphisms in schizophrenia candidate genes NRG1, DTNBP1, RGS4, G72/G30, and PIP5K2A. Patients were divided into the diagnostic subgroups of SZ-ND and SZ-D using the Schedule for Deficit Syndrome (SDS), and assessed clinically by the Positive and Negative Symptom Scale (PANSS). SNP8NRG241930 in NRG1 and rs1011313 in DTNBP1 were associated with SZ-ND (P = 0.04 and 0.03, respectively). Polymorphisms in RGS4, G72/G30, and PIP5K2A were neither associated with SZ-ND nor with SZ-D. SNP8NRG241930 showed association with the PANSS cognitive and hostility/excitability factors, rs1011313 with the negative factor and SDS total score, and rs10917670 in RGS4 was associated with the depression factor. Although these results replicate earlier findings about the genetic background of SZ-ND and SZ-D only partially, our data seem to confirm previously reported association of NRG1 with schizophrenia without prominent negative symptoms. It was possible to detect associations of small-to-medium effect size between the investigated candidate genes and symptom severity. Such studies have the potential to unravel the possible connection between genetic and clinical heterogeneity in schizophrenia.
The concept of deficit schizophrenia is regarded as one of the most promising attempts to reduce heterogeneity within schizophrenia. This paper summarizes the clinical, neurocognitive, brain imaging and electrophysiological correlates of this subtype of schizophrenia. Attempts to identify genetic and non-genetic risk factors are reviewed. Methodological limitations of studies supporting the efficacy of atypical antipsychotics in the treatment of the syndrome are highlighted. Two decades of research on deficit schizophrenia have failed to prove that it represents the extreme end of a severity continuum in schizophrenia, while some findings support the claim that it may be a separate disease entity.
Periods of recovery were examined in patients with and without deficit syndrome schizophrenia. Fifty-six patients with schizophrenia were studied, 39 of whom were divided into deficit and nondeficit syndrome schizophrenia subtypes using a proxy method. We also studied 39 nonpsychotic depressive comparison patients. Patients were evaluated as part of the Chicago Follow-up Study, which prospectively examined patients at regular intervals over a 20-year period. Using standardized instruments, patients were evaluated for the deficit syndrome, global recovery, rehospitalization, social dysfunction, occupational disability, and symptom presentation. Recovery was examined at 6 time points measured at 2-, 4.5-, 7.5-, 10-, 15-, and 20-year postindex hospitalization. Cumulatively, over the 20-year period, 13% of patients classified as meeting criteria for the deficit syndrome showed 1 or more 1-year periods of global recovery, in comparison to 63% of nondeficit schizophrenia patients and 77% of depressed patient controls. Results indicate that the deficit syndrome represents a persistently impaired subsample of schizophrenia patients, with continuous social, occupational, and symptom impairment. In contrast, nondeficit syndrome schizophrenia patients showed at least some periods of remission or recovery, with the likelihood of these periods increasing as they became older. Findings provide further support for the validity of the deficit syndrome concept and suggest that deficit status is characterized by a more persistently impaired course of illness and particularly poor long-term prognosis.
A wealth of studies has demonstrated that patients with schizophrenia are impaired in "theory of mind" (ToM). Here, we used a novel five-factor model of the Positive and Negative Syndrome Scale (PANSS) to test the hypothesis that selectivity of ToM deficits in schizophrenia depends on the predominating symptoms. We predicted that ToM impairments would be non-selective in patients with pronounced negative (NF) or disorganized symptoms (DF), whereas selective ToM impairment would occur in patients with predominant positive symptoms (PF). We recruited 50 patients diagnosed with schizophrenia or schizoaffective disorder and examined premorbid intelligence, executive functioning, ToM and psychopathology in comparison to a group of 29 healthy controls. Compared with healthy controls, patients performed more poorly on tasks involving executive functioning and ToM abilities. Using a novel PANSS five-factor model, we found a significant association of ToM deficits with the "disorganization" factor. Moreover, several individual PANSS items that were included within the disorganization factor correlated with impaired ToM, albeit the majority of correlations disappeared when controlled for executive functioning, and, to a lesser degree, when controlled for IQ. In addition, in the patient group we found interactions of poor ToM with symptoms belonging to the "emotional distress" factor of the PANSS. Contrary to expectations, associations of impaired ToM with positive symptoms were absent, and poor with regards to negative symptoms. This study lends further support to the assumption of differential associations of ToM deficits with individual symptoms and symptom clusters in schizophrenia.
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.
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.
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.
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.
The criteria for deficit schizophrenia were designed to define a group of patients with enduring, primary (or idiopathic) negative symptoms. In 2001, a review of the literature suggested that deficit schizophrenia constitutes a disease separate from nondeficit forms of schizophrenia. Here we provide a review of new studies, not included in that paper, in which patients with deficit schizophrenia and those with nondeficit schizophrenia were compared on dimensions typically used to distinguish diseases: signs and symptoms, course of illness, pathophysiological correlates, risk and etiological factors, and treatment response. Replicated findings and new evidence of double dissociation supporting the separate disease hypothesis are highlighted. Weaknesses in research and treatment options for these patients are also emphasized.
A large body of literature agrees that persons with schizophrenia suffer from a Theory of Mind (ToM) deficit. However, most empirical studies have focused on third-person, egocentric ToM, underestimating other facets of this complex cognitive skill. Aim of this research is to examine the ToM of schizophrenic persons considering its various aspects (first- vs. second-order, first- vs. third-person, egocentric vs. allocentric, beliefs vs. desires vs. positive emotions vs. negative emotions and how each of these mental state types may be dealt with), to determine whether some components are more impaired than others. We developed a Theory of Mind Assessment Scale (Th.o.m.a.s.) and administered it to 22 persons with a DSM-IV diagnosis of schizophrenia and a matching control group. Th.o.m.a.s. is a semi-structured interview which allows a multi-component measurement of ToM. Both groups were also administered a few existing ToM tasks and the schizophrenic subjects were administered the Positive and Negative Symptoms Scale and the WAIS-R. The schizophrenic persons performed worse than control at all the ToM measurements; however, these deficits appeared to be differently distributed among different components of ToM. Our conclusion is that ToM deficits are not unitary in schizophrenia, which also testifies to the importance of a complete and articulated investigation of ToM.
The Schedule for the Deficit Syndrome (SDS) is an instrument for categorizing schizophrenic patients into those with and those without the deficit syndrome. In a study of 40 schizophrenic patients diagnosed by DSM-III criteria, raters using the SDS demonstrated good interrater reliability for this categorization, as well as for individual negative symptoms and a rating of global severity.
The authors provide a rationale for distinguishing the primary, enduring negative symptoms of schizophrenia (termed "deficit symptoms") from the more transient negative symptoms secondary to other factors. They argue that the former are more likely to provide a basis for meaningful subtyping of the schizophrenic syndrome, while the latter are more likely to respond to currently available treatments. They describe their experience in using clinical judgment based on longitudinal observations to identify deficit and nondeficit subtypes of schizophrenic patients and propose criteria for defining schizophrenia with the deficit syndrome.
The variable results of positive-negative research with schizophrenics underscore the importance of well-characterized, standardized
measurement techniques. We report on the development and initial standardization of the Positive and Negative Syndrome Scale
(PANSS) for typological and dimensional assessment. Based on two established psychiatric rating systems, the 30-item PANSS
was conceived as an operationalized, drug-sensitive instrument that provides balanced representation of positive and negative
symptoms and gauges their relationship to one another and to global psychopathology. It thus constitutes four scales measuring
positive and negative syndromes, their differential, and general severity of illness. Study of 101 schizophrenics found the
four scales to be normally distributed and supported their reliability and stability. Positive and negative scores were inversely
correlated once their common association with general psychopathology was extracted, suggesting that they represent mutually
exclusive constructs. Review of five studies involving the PANSS provided evidence of its criterion-related validity with
antecedent, genealogical, and concurrent measures, its predictive validity, its drug sensitivity, and its utility for both
typological and dimensional assessment.
Previous studies have found a subgroup of people with autism or Asperger Syndrome who pass second-order tests of theory of mind. However, such tests have a ceiling in developmental terms corresponding to a mental age of about 6 years. It is therefore impossible to say if such individuals are intact or impaired in their theory of mind skills. We report the performance of very high functioning adults with autism or Asperger Syndrome on an adult test of theory of mind ability. The task involved inferring the mental state of a person just from the information in photographs of a person's eyes. Relative to age-matched normal controls and a clinical control group (adults with Tourette Syndrome), the group with autism and Asperger Syndrome were significantly impaired on this task. The autism and Asperger Syndrome sample was also impaired on Happé's strange stories tasks. In contrast, they were unimpaired on two control tasks: recognising gender from the eye region of the face, and recognising basic emotions from the whole face. This provides evidence for subtle mindreading deficits in very high functioning individuals on the autistic continuum.
"Theory of mind" (ToM) means the ability to represent others' intentions, knowledge and beliefs and interpret them. Children with autism typically fail tasks aimed at assessing their understanding of false beliefs. These features of autism are strikingly similar to some negative features of schizophrenia. Mental abilities were studied in 35 schizophrenics (DSM-IV) and 17 normal controls. Subjects heard four ToM stories and simultaneously were shown cartoons depicting the action occurring in the stories. All stories involved false beliefs or deception. As for the current symptomatology, schizophrenics were divided according to Liddle's three-dimensional model (reality distortion, psychomotor poverty, disorganisation). Our results show significant differences between schizophrenics and normal controls in all ToM stories, with schizophrenic people performing worse than controls. In first-order stories (a false belief about the state of the world) significant differences were found among symptom dimensions, with the psychomotor poverty group performing worse than disorganisation subjects and reality distortion ones. As for second-order stories (a false belief about the belief of another character), the psychomotor poverty group performed worse than the other groups only in one of the four ToM stories. More research in separating ToM deficits from attention disturbances is needed.
In 1997 in this Journal we published the "Reading the Mind in the Eyes" Test, as a measure of adult "mentalising". Whilst that test succeeded in discriminating a group of adults with Asperger syndrome (AS) or high-functioning autism (HFA) from controls, it suffered from several psychometric problems. In this paper these limitations are rectified by revising the test. The Revised Eyes Test was administered to a group of adults with AS or HFA (N = 15) and again discriminated these from a large number of normal controls (N = 239) drawn from different samples. In both the clinical and control groups the Eyes Test was inversely correlated with the Autism Spectrum Quotient (the AQ), a measure of autistic traits in adults of normal intelligence. The Revised Eyes Test has improved power to detect subtle individual differences in social sensitivity.
Previous studies have suggested that deficit schizophrenia is a stable subtype of schizophrenia, and that patients with the deficit schizophrenia have different course of illness from other people with schizophrenia. We tested the ability of the deficit/nondeficit categorization to predict clinical features at five years' followup in a group of chronically ill outpatients. Outpatients categorized into deficit (N = 46) and nondeficit (N = 174) schizophrenia were assessed at an average of five years after the categorization was made. Raters making the followup assessments were blind to the initial categorization. At followup, the deficit patients had poorer quality of life, poorer social and occupational function, and more severe negative symptoms. Despite these differences, deficit patients were less distressed (as measured by depressive mood, anxiety, and guilt), and they did not have more severe hallucinations, delusions, thought disorder. These differences could not be attributed to demographic differences. The group differences in quality of life and level of psychosocial function remained significant after accounting for the severity of baseline negative symptoms. These findings confirm that patients with the deficit schizophrenia have a set of relatively stable clinical features that are associated with poor outcome.
Baron-Cohen [Mindblindness: an essay on autism and theory of mind. Cambridge, MA: MIT Press, 1997] has suggested that the interpretation of gaze plays an important role in a normal functioning theory of mind (ToM) system. Consistent with this suggestion, functional imaging research has shown that both ToM tasks and eye gaze processing engage a similar region of the posterior superior temporal sulcus (STS). However, a second brain region associated with ToM, the medial prefrontal (MPF) cortex, has not been identified by previous eye gaze studies. We discuss the methodological issues that may account for the absence of MPF activation in these experiments and present a PET study that controls for these factors. Our experiment included three conditions in which the proportions of faces gazing at, and away from, the participant, were as follows: 100% direct [0% averted], 50% direct-50% averted, and 100% horizontally averted [0% direct]. Two control conditions were also included in which the faces' gaze were averted down, or their eyes were closed. Contrasts comparing the gaze conditions with each of the control conditions revealed medial frontal involvement. Parametric analyses showed a significant linear relationship between increasing proportions of horizontally averted gaze and increased rCBF in the MPF cortex. The opposite parametric analysis (increasing proportions of direct gaze) was associated with increased rCBF in a number of areas including the superior and medial temporal gyri. Additional subtraction contrasts largely confirmed these patterns. Our results demonstrate a considerable degree of overlap between the medial frontal areas involved in eye gaze processing and theory of mind tasks.
Several clinical and research applications require an estimation of therapeutic dose equivalence across antipsychotic medications. Since the advent of the newer atypical antipsychotics, new dose equivalent estimations have been needed.
The reported minimum effective dose was identified for each newer atypical antipsychotic medication and for haloperidol across all available fixed-dose placebo-controlled studies. Reported minimum effective dose equivalence ratios to haloperidol were then converted to chlorpromazine equivalents using the "2 mg of haloperidol equals 100 mg of chlorpromazine" convention.
To identify the fixed-dose studies, the following sources were searched until June 2002: MEDLINE, the bibliographies of identified reports, published meta-analyses and reviews, Cochrane reviews, Freedom of Information Act material available from the Food and Drug Administration, and abstracts from several scientific meetings from 1997 to 2002.
Doses equivalent to 100 mg/day of chlorpromazine were 2 mg/day for risperidone, 5 mg/day for olanzapine, 75 mg/day for quetiapine, 60 mg/day for ziprasidone, and 7.5 mg/day for aripiprazole.
These equivalency estimates may be useful for clinical and research purposes. The source of the dose equivalency estimation is evidence-based and consistent across medication.
The aim of this study was to reexamine and compare the characteristics of the deficit and nondeficit schizophrenic patients. This cross-sectional study consisted of 62 in- and out-patients, 18-65 years of age, diagnosed with schizophrenia according to DSM-IV. The sociodemographic variables, premorbid adjustment, clinical course and general functioning level in the past five years were evaluated by utilizing the appropriate sections of Comprehensive Assessment of Symptoms and History (CASH). In addition, GAF, the Schedule for the Deficit Syndrome (SDS), Positive and Negative Syndrome Scale (PANSS), Montgomery Asberg Depression Scale (MADRS), the Neurological Evaluation Scale (NES) and the Simpson Angus Extrapyramidal Side Effects (EPS) Rating Scale, Trail A and B, Verbal Fluency, Stroop, Block Design and Finger Tapper tests were administered. Using the SDS, 19 patients (30.6 %) were categorized as deficit; 43 (69.4 %) were categorized as nondeficit. The deficit patients were worse on the Functioning During Past Five Years score of CASH. The PANSS and MADRS mean scores were not significantly different between the two groups, except a higher level of negative symptoms observed in the deficit group. NES scores were also significantly higher in the deficit group. However, sociodemographic and other clinical variables, neurocognitive measures and EPS symptoms did not show any significant difference between the two groups. Our findings suggest that the deficit schizophrenia is a distinct subgroup comprised of patients who have more negative symptoms, neurological impairment and poor functioning which may have a common underlying pathology.