Moral learning and positive schizotypy: Social cognitive mechanisms in psychosis- proneness

BACKGROUND

Delusional thoughts such as paranoia and conspiratorial thinking reflect beliefs in others' intentions to do harm. Given the integral role of harm evaluation in moral cognition, a better understanding of how psychosis-prone individuals process others' moral characters may provide insights into social cognitive mechanisms of these types of delusions.

METHODS

An online sample of 293 participants was drawn from the general population, using Amazon Mechanical Turk. Participants performed a moral inference task, where they predicted and judged the binary choices of two fictitious agents ("good" or "bad") to impose harm under different levels of financial incentives. An investment game involving the same agents then examined participants' trust behavior. Psychosis-proneness was measured with the Multidimensional Schizotypy Scale Brief Edition.

RESULTS

A set of multiple regressions showed that positive schizotypy was associated with a lower yet more confident pre-experimental expectation of the agent's moral character, lower prediction accuracy of the agent's harm preferences, less belief revision, and undifferentiated perception of the good and bad agents' characters. Positive schizotypy was also related to higher expectations for reciprocity in the investment game, regardless of agent characters.

CONCLUSION

Our findings suggest that inflexible beliefs associated with psychosis-proneness extend beyond negative prior expectations, also reflecting difficulties in moral learning. The resulting undifferentiated moral impressions might contribute to undue suspicion of benevolent individuals and increased gullibility to malicious ones, potentially further strengthening conspiratorial beliefs.

Towards a scalable approach to assess speech organization across the psychosis-spectrum -online assessment in conjunction with automated transcription and extraction of speech measures

Automatically extracted measures of speech constitute a promising marker of psychosis as disorganized speech is associated with psychotic symptoms and predictive of psychosis-onset. The potential of speech markers is, however, hampered by (i) lengthy assessments in laboratory settings and (ii) manual transcriptions. We investigated whether a short, scalable data collection (online) and processing (automated transcription) procedure would provide data of sufficient quality to extract previously validated speech measures. To evaluate the fit of our approach for purpose, we assessed speech in relation to psychotic-like experiences in the general population. Participants completed an 8-minute-long speech task online. Sample 1 included measures of psychometric schizotypy and delusional ideation (N = 446). Sample 2 included a low and high psychometric schizotypy group (N = 144). Recordings were transcribed both automatically and manually, and connectivity, semantic, and syntactic speech measures were extracted for both types of transcripts. 73%/86% participants in sample 1/2 completed the experiment. Nineteen out of 25 speech measures were strongly (r > 0.7) and significantly correlated between automated and manual transcripts in both samples. Amongst the 14 connectivity measures, 11 showed a significant relationship with delusional ideation. For the semantic and syntactic measures, On Topic score and the Frequency of personal pronouns were negatively correlated with both schizotypy and delusional ideation. Combined with demographic information, the speech markers could explain 11-14% of the variation of delusional ideation and schizotypy in Sample 1 and could discriminate between high-low schizotypy with high accuracy (0.72-0.70, AUC = 0.78-0.79) in Sample 2. The moderate to high retention rate, strong correlation of speech measures across manual and automated transcripts and sensitivity to psychotic-like experiences provides initial evidence that online collected speech in combination with automatic transcription is a feasible approach to increase accessibility and scalability of speech-based assessment of psychosis.

Cold executive function processes and their hot analogs in schizotypy

OBJECTIVE

To examine cold (based on logical reasoning) versus hot (having emotional components) executive function processes in groups with high individual schizotypal traits.

METHOD

Two-hundred and forty-seven participants were administered the Schizotypal Personality Questionnaire and were allocated into schizotypal (cognitive-perceptual, paranoid, negative, disorganized) or control groups according to pre-specified criteria. Participants were also administered a battery of tasks examining working memory, complex selective attention, response inhibition, decision-making and fluid intelligence and their affective counterparts. The outcome measures of each task were reduced to one composite variable thus formulating five cold and five hot cognitive domains. Between-group differences in the cognitive domains were examined with repeated measures analyses of covariance.

RESULTS

For working memory, the control and the cognitive-perceptual groups outperformed negative schizotypes, while for affective working memory controls outperformed the disorganized group. Controls also scored higher compared with the disorganized group in complex selective attention, while both the control and the cognitive-perceptual groups outperformed negative schizotypes in complex affective selective attention. Negative schizotypes also had striking difficulties in response inhibition, as they scored lower compared with all other groups. Despite the lack of differences in fluid intelligence, controls scored higher compared with all schizotypal groups (except from cognitive-perceptual schizotypes) in emotional intelligence; the latter group reported higher emotional intelligence compared with negative schizotypes.

CONCLUSION

Results indicate that there is no categorical association between the different schizotypal dimensions with solely cold or hot executive function processes and support impoverished emotional intelligence as a core feature of schizotypy.

Mnemonic discrimination deficits in multidimensional schizotypy

Current developmental psychopathology models indicate that schizophrenia can be understood as the most extreme expression of a multidimensional continuum of symptoms and impairment referred to as schizotypy. In nondisordered adults, schizotypy predicts risk for developing schizophrenia-spectrum psychopathology. Schizophrenia is associated with disruptions in detecting subtle differences between objects, which is linked to hippocampal dysfunction. These disruptions have been shown in the Mnemonic Similarity Task (MST) when patients are less likely to reject lures that are similar but not identical to studied objects, and instead mistake them for studied items. This pattern of errors may be a behavioral manifestation of impaired pattern separation, a key episodic memory ability associated with hippocampal integrity and overreliance on pattern completion. We examined whether multidimensional schizotypy is associated with such deficits in nondisordered young adults. Participants (n = 230) were assessed for positive, negative, and disorganized schizotypy and completed the MST and a perceptual discrimination task. MST performance showed that a combination of elevated negative and disorganized schizotypy was associated with decreased rejections of similar lures because they were mistakenly identified as studied items. These deficits were not observed in traditional recognition measures within the same task, nor in perceptual discrimination, suggesting that mnemonic discrimination deficits assessed by MST were selective and did not reflect generalized deficits. These findings extend the results obtained in schizophrenia patients and support a multidimensional model of schizophrenia-spectrum psychopathology.

Online speech assessment of the psychotic spectrum: Exploring the relationship between overlapping acoustic markers of schizotypy, depression and anxiety

BACKGROUND

Remote assessment of acoustic alterations in speech holds promise to increase scalability and validity in research across the psychosis spectrum. A feasible first step in establishing a procedure for online assessments is to assess acoustic alterations in psychometric schizotypy. However, to date, the complex relationship between alterations in speech related to schizotypy and those related to comorbid conditions such as symptoms of depression and anxiety has not been investigated. This study tested whether (1) depression, generalized anxiety and high psychometric schizotypy have similar voice characteristics, (2) which acoustic markers of online collected speech are the strongest predictors of psychometric schizotypy, (3) whether including generalized anxiety and depression symptoms in the model can improve the prediction of schizotypy.

METHODS

We collected cross-sectional, online-recorded speech data from 441 participants, assessing demographics, symptoms of depression, generalized anxiety and psychometric schizotypy.

RESULTS

Speech samples collected online could predict psychometric schizotypy, depression, and anxiety symptoms with weak to moderate predictive power, and with moderate and good predictive power when basic demographic variables were added to the models. Most influential features of these models largely overlapped. The predictive power of speech marker-based models of schizotypy significantly improved after including symptom scores of depression and generalized anxiety in the models (from R2 = 0.296 to R2 = 0. 436).

CONCLUSIONS

Acoustic features of online collected speech are predictive of psychometric schizotypy as well as generalized anxiety and depression symptoms. The acoustic characteristics of schizotypy, depression and anxiety symptoms significantly overlap. Speech models that are designed to predict schizotypy or symptoms of the schizophrenia spectrum might therefore benefit from controlling for symptoms of depression and anxiety.

Working memory and sensory memory in subclinical high schizotypy: An avenue for understanding schizophrenia?

The search for robust, reliable biomarkers of schizophrenia remains a high priority in psychiatry. Biomarkers are valuable because they can reveal the underlying mechanisms of symptoms and monitor treatment progress and may predict future risk of developing schizophrenia. Despite the existence of various promising biomarkers that relate to symptoms across the schizophrenia spectrum, and despite published recommendations encouraging multivariate metrics, they are rarely investigated simultaneously within the same individuals. In those with schizophrenia, the magnitude of purported biomarkers is complicated by comorbid diagnoses, medications and other treatments. Here, we argue three points. First, we reiterate the importance of assessing multiple biomarkers simultaneously. Second, we argue that investigating biomarkers in those with schizophrenia-related traits (schizotypy) in the general population can accelerate progress in understanding the mechanisms of schizophrenia. We focus on biomarkers of sensory and working memory in schizophrenia and their smaller effects in individuals with nonclinical schizotypy. Third, we note irregularities across research domains leading to the current situation in which there is a preponderance of data on auditory sensory memory and visual working memory, but markedly less in visual (iconic) memory and auditory working memory, particularly when focusing on schizotypy where data are either scarce or inconsistent. Together, this review highlights opportunities for researchers without access to clinical populations to address gaps in knowledge. We conclude by highlighting the theory that early sensory memory deficits contribute negatively to working memory and vice versa. This presents a mechanistic perspective where biomarkers may interact with one another and impact schizophrenia-related symptoms.

Examining Cognitive Biases Uniquely Associated with Schizotypy

INTRODUCTION

Individuals with schizotypy can experience a number of cognitive biases that may increase their risk in developing schizophrenia-spectrum psychopathology. However, cognitive biases are also present in mood and anxiety disorders, and it is currently unclear which biases are specific to schizotypy and which may be a result of comorbid depression and/or anxiety.

METHODS

462 participants completed measures of depression, anxiety, cognitive biases, cognitive schemas, and schizotypy. Correlation analyses were conducted to examine the relationship between these constructs. Three hierarchical regression analyses were conducted to examine if schizotypy, depression, and anxiety explained a statistically significant amount of variance in cognitive biases after controlling for depression and anxiety, schizotypy and anxiety, and schizotypy and depression, respectively. Moderated regression analyses were also conducted to investigate the moderating role of biological sex and ethnicity in the association between cognitive biases and schizotypy.

RESULTS

Self-referential processing, belief inflexibility, and attention for threat were associated with schizotypy. The belief inflexibility bias and social cognition problems were specifically associated with schizotypy after controlling for depression and anxiety and were not directly associated with either depression or anxiety. These associations were not moderated by biological sex or ethnicity.

CONCLUSION

The belief inflexibility bias may be an important cognitive bias underlying schizotypal personality, and further research will be important to determine whether this bias is also associated with an increased likelihood of transitioning to psychosis.

The Indirect Effect of Peritraumatic Dissociation on the Relationship Between Childhood Maltreatment and Schizotypy

Schizotypy is a multidimensional personality construct that is understood as a vulnerability for schizophrenia, often manifesting as more subtle and attenuated symptoms, referred to as schizotypic psychopathology. It has many well-established environmental risk factors, including experiencing childhood maltreatment (CM), but the intermediary mechanisms that relate CM to schizotypic psychopathology are unclear. Prior studies have demonstrated that trait dissociation may indirectly affect the relationship between CM and schizotypic psychopathology. However, less is known about the importance of peritraumatic dissociative experiences during CM and how it relates to schizotypic symptom manifestations in young adulthood. Therefore, the present study explored the independent contributions of peritraumatic and trait dissociation in the relationship between CM and schizotypy. Participants (N = 346) were undergraduate students who completed online self-report measures on CM, trait dissociation, peritraumatic dissociation experienced during CM, and schizotypic symptoms. The indirect effect of peritraumatic dissociation and trait dissociation on the relationship between CM and schizotypy was examined using mediational analyses. Correlational analyses revealed significant associations between self-reported CM, schizotypy, trait dissociation, and peritraumatic dissociation. In addition, mediational analyses indicated a significant indirect effect of peritraumatic dissociation (β = .06, 95% confidence interval (CI) [0.01, 0.12]), but not trait dissociation (β = .05, 95% CI [-0.02, 0.12]), on CM and schizotypy. These results highlight peritraumatic dissociation as an important mechanism driving the expression of schizotypic symptoms among individuals with a history of CM. Understanding how trauma sequelae lead to schizotypic psychopathology may be crucial in assessing and treating individuals with maltreatment histories or those on the psychosis spectrum.

Visual Verbal Information Processing under Conditions of Reading and Categorization in Schizotypy: An Event-Related Brain Potential Study

BACKGROUND

Some individuals exhibit symptoms that resemble schizophrenia, but these manifestations are less in the degree to those seen in schizophrenia. Such a latent personality construct has been called schizotypy. It is known that schizotypal personality traits have an impact on cognitive control and semantic processing. The present study aimed to examine whether visual verbal information processing is modulated by enhancement of top-down processes applied to different words within one phrase in subjects with schizotypal personality traits. The tasks employed were based on differences in the involvement of cognitive control in visual verbal information processing and hypothesized that subjects with schizotypal traits would demonstrate failure in top-down modulation of word processing within a phrase.

METHODS

Forty-eight healthy undergraduate students were enrolled in the study. Participants were screened for schizotypy with the Schizotypal Personality Questionnaire. Word combinations consisting of an attribute and a noun were used as stimuli. Participants were asked to categorize one word in a phrase and to passively read the other word in the pair. To obtain neurophysiological data during task performance, the event-related brain potential N400 was measured.

RESULTS

In the low schizotypy scores group, an increased N400 amplitude was revealed for both attributes and nouns during passive reading compared to categorization. This effect was not observed in the high schizotypy scores group; therefore, word processing was modulated weakly by the experimental task in subjects with schizotypal personality traits.

CONCLUSIONS

Changes observed in schizotypy can be regarded as a failure in top-down modulation of word processing within a phrase.

[Teraligen in the complex treatment of anxiety-phobic, behavioral and depressive syndromes in children and adolescents with schizotypal disorder]

ABSTRUCT

OBJECTIVE

To determine the frequency of prescribing and the main therapeutic targets of Teraligen in the treatment of Schizotypal disorder (STD) in childhood and adolescence.

MATERIAL AND METHODS

The sample consisted of 151 patients aged 7 to 16 years with a diagnosis of STD (F 21), of which 31.1% (n=47) of female patients and 68.9% (n=104) of male patients who received inpatient or outpatient treatment at the FSBI NCPZ from 2008 to 2020. The study was conducted by clinical-psychopathological, clinical-catamnestic, and statistical methods.

RESULTS

Teraligen was prescribed by psychiatrists to patients with STD in 74.2% of cases, of which in 46.4% of cases patients received Teraligen even before the diagnosis of STD in connection with complaints of neurotic disorders (anxiety, fears and sleep disorders) (n=30), as well as in connection with autistic-like behavior (n=22). At the time of follow-up, 55% (n=83) of patients received Teraligen, of which 63.9% (n=53) of patients were prescribed it for the first time. The applied schemes of prescribing Teraligen for the treatment of anxiety-phobic, depressive and behavioral syndromes within the framework of the STD in a relatively age-related aspect are presented.

CONCLUSION

The high frequency of prescribing Teraligen by psychiatrists and neurologists to children and adolescents with STD at different stages of observation is shown, which reflects the confidence of specialists in this drug. Teraligen has demonstrated a multidimensional pharmacological effect, including a mild antipsychotic effect, providing reduction of a wide range of psychopathological symptoms, with good tolerability and drug interaction. The study of the possibilities of Teraligen, both for monotherapy and for augmentation of the treatment of mental pathology in childhood, remains relevant.

[Non-suicidal self-injurious behavior in conduct disorders and schizotypal disorder]

OBJECTIVE

To compare the methods and motives of non-suicidal self-injurious behavior (NSIB) in conduct disorders and schizotypal disorder.

MATERIAL AND METHODS

The main group consisted of 91 patients (77.8%), aged 13-24 years, with behavioral disorders and NSIB, who completed questionnaires using the self-harm statements questionnaire. The younger subgroup consisted of 54 patients under the age of 18 with a diagnosis of «Behavior Disorders» (ICD-10 F91), the older subgroup included 37 patients aged 18 years or more with a diagnosis of Emotionally Unstable Personality Disorder (F60.3). The comparison group consisted of 100 patients, aged 13-41 years with a diagnosis of schizotypal disorder (F21) and NSIB. We used clinical-psychopathological, standardized and statistical methods.

RESULTS

Significant differences were revealed in the sexual preference for NSIB (p=0.0001), a number of leading types of NSIB, and the absence of differences in the motives of self-injurious behavior in patients of the compared groups. In the comparison group, cuts and cauterization prevailed as the leading type of NSIB, in patients with behavioral disorders prevailed obstacles to wound healing, which is hypothetically associated with the influence of obsessive psychopathological mechanisms, since pathological excoriation has the same nature as obsessive-compulsive disorder and is included with it in the same DSM-5 category. The impulsive subtype of NSIB observed in this situation usually arises due to an increasing sense of tension and is associated with the motive of intrapersonal self-regulation.

CONCLUSION

The study showed that the difference between the compared nosological groups according to the methods and motives of self-harming actions is determined not so much by intergroup differences as by sex and age patterns within each of the compared groups. This allows us to talk about the proximity of the mechanisms of self-harm in various mental disorders, and the phenomenon of NSIB itself should be considered rather as a nosologically nonspecific psychopathological phenomenon.

The interrelationship between schizotypy, clinical high risk for psychosis and related symptoms: Cognitive disturbances matter

Schizotypy and clinical high risk (CHR) criteria can identify individuals who are at increased risk for developing psychosis in community and patient samples. However, both approaches have rarely been combined, and very little is known about their associations. Therefore, we examined the factorial structure of CHR and related symptoms and schizotypy features as well as their interrelationship for the first time in a comprehensive approach. In a sample of 277 patients (22 ± 6 years) from two early detection services, structural equation modeling including confirmatory factor analysis was performed to test a theory-driven model using four Wisconsin Schizotypy Scales, 14 predictive basic symptoms (BS) of the Schizophrenia Proneness Instrument, and positive, negative, and disorganized symptoms from the Structured Interview for Psychosis-Risk Syndromes. The data fitted well to the six hypothesized latent factors consisting of negative schizotypy, positive schizotypy including perceptual BS, negative symptoms, positive symptoms, disorganized symptoms and cognitive disturbances. As postulated, schizotypy features were significantly associated with positive, negative and disorganized symptoms through cognitive disturbances. Additionally, positive and negative schizotypy also had a direct association with the respective symptom-domain. While the identified factorial structure corresponds well to dimensional models of schizotypy and psychoses, our model extends earlier models by indicating that schizotypy features are associated with positive, negative and disorganized symptoms directly or indirectly via subjective cognitive disturbances. This calls for more attention to subjective cognitive deficits in combination with heightened schizotypy in the early detection and intervention of psychoses - or even of an Attenuated Psychosis Syndrome.

Integrated assessment of visual perception abnormalities in psychotic disorders and relationship with clinical characteristics

BACKGROUND

The visual system is recognized as an important site of pathology and dysfunction in schizophrenia. In this study, we evaluated different visual perceptual functions in patients with psychotic disorders using a potentially clinically applicable task battery and assessed their relationship with symptom severity in patients, and with schizotypal features in healthy participants.

METHODS

Five different areas of visual functioning were evaluated in patients with schizophrenia and schizoaffective disorder (n = 28) and healthy control subjects (n = 31) using a battery that included visuospatial working memory (VSWM), velocity discrimination (VD), contour integration, visual context processing, and backward masking tasks.

RESULTS

The patient group demonstrated significantly lower performance in VD, contour integration, and VSWM tasks. Performance did not differ between the two groups on the visual context processing task and did not differ across levels of interstimulus intervals in the backward masking task. Performances on VSWM, VD, and contour integration tasks were correlated with negative symptom severity but not with other symptom dimensions in the patient group. VSWM and VD performances were also correlated with negative sychizotypal features in healthy controls.

CONCLUSION

Taken together, these results demonstrate significant abnormalities in multiple visual processing tasks in patients with psychotic disorders, adding to the literature implicating visual abnormalities in these conditions. Furthermore, our results show that visual processing impairments are associated with the negative symptom dimension in patients as well as healthy individuals.

Differential impairment of positive and negative schizotypy in list-method and item-method directed forgetting

Schizophrenia is characterized by cognitive impairment and this impairment is expected to occur, albeit to a lesser degree, in people putatively at risk for schizophrenia. Two experiments assessed the relationship between directed forgetting (DF) and schizotypy, which is a multidimensional construct that reflects the expression of the underlying vulnerability for schizophrenia. Experiment 1 involved item-method DF and Experiment 2 involves list-method DF study. The schizotypy dimensions exhibited differential patterns of impairment across the 2 methods that suggest different underlying processes. Positive schizotypy showed impairment in item-method DF that was driven by reduced ability to forget forget-cued items, whereas performance on remember-cued items was unaffected in positive schizotypy. Despite the deficit in item-method DF, positive schizotypy participants showed preserved performance in list-method DF. The opposite pattern was found in negative schizotypy participants, who showed impairment in list-method DF, despite preserved performance in item-method DF. Negative schizotypy was previously associated with deficits in context processing and, consistent with context-change account of list-method DF, showed deficits in list-method DF task. Positive schizotypy is characterized by deficits in inhibitory control and, consistent with inhibitory account of item-method DF, showed deficits in item-method DF task. Collectively, these results (a) suggest that different DF methods involve different underlying mechanisms, (b) support the context-account of list-method DF and an inhibitory account of item-method DF, and (c) support the multidimensional model of schizotypy by showing differential impairment in positive and negative schizotypy across the 2 DF tasks. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Prediction of prodromal symptoms and schizophrenia-spectrum personality disorder traits by positive and negative schizotypy: A 3-year prospective study

The present study extends previous cross-sectional findings by examining the predictive validity of positive and negative schizotypy in a young adult sample at a three-year follow-up. Schizotypy and schizophrenia share a comparable multidimensional structure with positive and negative dimensions being the most strongly supported factors. Previous cross-sectional and longitudinal studies employing the psychometric high-risk strategy indicated that schizotypy is a useful method for identifying risk and resilience factors for the development of schizophrenia-spectrum psychopathology. In the present study, 103 participants (77% of 134 candidate participants) were reassessed at a three-year follow-up. As hypothesized, positive schizotypy predicted psychotic-like symptoms, depression, low self-esteem, and general psychopathology. Negative schizotypy predicted emotional disturbances, schizoid personality traits, and mental health treatment during the past year. As expected, both schizotypy dimensions predicted schizotypal, paranoid, and avoidant personality traits, and impaired functioning. These longitudinal findings provide additional evidence supporting the multidimensional model of schizotypy as a valid framework for studying etiological mechanisms and trajectories of psychosis.

Do complaints of everyday cognitive failures in high schizotypy relate to emotional working memory deficits in the lab?

BACKGROUND

Individuals high on schizotypy complain of increased cognitive failures in everyday life. However, the neuropsychological performance of this group does not consistently indicate underlying ability deficits. It is possible that current neuropsychological tests lack ecological validity. Given the increased affective reactivity of high schizotypes, they may be more sensitive to emotional content interfering with cognitive ability. This study sought to explore whether an affective n-back working memory task would elicit impaired performance in schizotypy, echoing complaints concerning real world cognition.

METHODS

127 healthy participants completed self-report measures of schizotypy and cognitive failures and an affective n-back working memory task. This task was varied across three levels of load (1- to 3-back) and four types of stimulus emotion (neutral, fearful, happy, sad). Differences between high (n=39) and low (n=48) schizotypy groups on performance outcomes of hits and false alarms were examined, with emotion and load as within-groups variables.

RESULTS

As expected, high schizotypes reported heightened vulnerability to cognitive failures. They also demonstrated a relative working memory impairment for emotional versus neutral stimuli, whereas low schizotypes did not. High schizotypes performed most poorly in response to fearful stimuli. For false alarms, there was an interaction between schizotypy, load, and emotion, such that high schizotypy was associated with deficits in response to fearful stimuli only at higher levels of task difficulty. Inclusion of self-reported cognitive failures did not account for this.

CONCLUSION

These findings suggest that the "gap" between subjective and objective cognition in schizotypy may reflect the heightened emotional demands associated with cognitive functioning in the real world, although other factors also seem to play a role. There is a need to improve the ecological validity of objective assessments, whilst also recognizing that self-reported cognitive failures tap into a range of factors difficult to assess in the lab, including emotion. Cognitive interventions for at-risk individuals will likely be more beneficial if they address emotional processing alongside other aspects of cognition.

Objective and subjective olfaction across the schizophrenia spectrum

Much research indicates that patients with schizophrenia have impaired olfaction detection ability. However, studies of individuals with psychometrically defined schizotypy reveal mixed results-some document impairments while others do not. In addition to deficits in objective accuracy in olfaction for patients with schizophrenia, there has been an interest in subjective experience of olfaction. Unfortunately, methods of assessing accuracy and subjective hedonic olfactory evaluations in prior studies may not have been sensitive enough to detect group differences in this area. This study employed a measure of olfactory functioning featuring an expanded scoring system to assess both accuracy and subjective evaluations of pleasant and unpleasant experience. Data were collected for patients with schizophrenia, young adults with psychometrically defined schizotypy, psychiatric outpatients, and healthy controls. Results of this study indicate that both the schizophrenia and outpatient psychiatric groups showed similar levels of impaired olfaction ability; however, the schizotypy group was not impaired in olfaction detection. Interestingly, with regard to subjective hedonic evaluation, it was found that patients with schizophrenia did not differ from psychiatric outpatients, whereas individuals with schizotypy tended to rate smells as significantly less pleasant than healthy control participants. This suggests that subjective olfactory assessment is abnormal in some manner in schizotypy. It also suggests that accuracy of olfaction identification may be a characteristic of severe mental illness across severe mental illness diagnoses. The results are potentially important for understanding olfaction deficits across the mental illness spectrum.

How are autism and schizotypy related? Evidence from a non-clinical population

Both autism spectrum conditions (ASCs) and schizophrenia spectrum conditions (SSCs) involve altered or impaired social and communicative functioning, but whether these shared features indicate overlapping or different etiological factors is unknown. We outline three hypotheses (overlapping, independent, and diametric) for the possible relationship between ASCs and SSCs, and compare their predictions for the expected relationships between autistic and schizotypal phenotypes using the Autism Spectrum Quotient and the Schizotypal Personality Questionnaire-Brief Revised from a large non-clinical sample of undergraduate students. Consistent with previous research, autistic features were positively associated with several schizotypal features, with the most overlap occurring between interpersonal schizotypy and autistic social and communication phenotypes. The first component of a principal components analysis (PCA) of subscale scores reflected these positive correlations, and suggested the presence of an axis (PC1) representing general social interest and aptitude. By contrast, the second principal component (PC2) exhibited a pattern of positive and negative loadings indicative of an axis from autism to positive schizotypy, such that positive schizotypal features loaded in the opposite direction to core autistic features. These overall PCA patterns were replicated in a second data set from a Japanese population. To evaluate the validity of our interpretation of the PCA results, we measured handedness and mental rotation ability, as these are established correlates of SSCs and ASCs, respectively. PC2 scores were significantly associated with hand preference, such that increasingly 'schizotypal' scores predicted reduced strength of handedness, which is consistent with previous research. PC1 scores were positively related to performance on the mental rotation task, suggesting trade-offs between social skills and visual-spatial ability. These results provide novel evidence for an autism-positive schizotypy axis, and highlight the importance of recognizing that psychological variation involving reduced social interest and functioning may have diverse causes.

Marked elevation of transaminases and pancreatic enzymes in severe malnourished male with eating disorder

We report a case of a 45 year old Caucasian malnourished male with an history of eating disorder who developed severe liver and pancreatic damage and multiorgan disfunction. At admission to our department, his body mass index (BMI) was 11.1. Biochemical evaluation showed elevated serum levels of transaminases (AST= 2291 U/L, ALT= 1792 U/L), amylase (3620 U/L), lipase (4102 U/L), CPK= 1370 U/L, LDH= 2082 U/L. No other cause of acute liver and pancreatic damage was evidenced. Haematological disorders (anemia, thrombocytopenia, leukopenia) found on admission seem related to bone marrow hypoplasia and to gelatinous marrow transformation described in severe state of malnutrition. Although a moderate increase in liver and pancreatic enzymes are a common finding in malnourished patients, only a small number of reports describes severe liver injury and multiorgan dysfunction. After a few days of treatment (hydration and nutritional support) a marked decrease of serum transaminases, lipase, amylase, CPK, LDH occurred, despite a transient increase in these levels secondary to refeeding syndrome. The association of chronic malnutrition and a decrease in systemic perfusion may be responsible for multiorgan dysfunction. In our patient the high levels of transaminases and pancreatic enzymes were the most important biochemical abnormalities normalized after refeeding.

[Cognitive functions, social functioning and self-esteem in young male patients with adolescence onset schizotypal disorder]

The results of psychological examination of 33 male patients with a diagnosis of schizotypal disorder (SD), mean age 22 years, with age at onset in adolescence and 20 healthy young men are presented. Cognitive performance in patients with SD did not differ from healthy people on all measures, with the exception of social adaptation. There was a trend towards the change of normative responses and, respectively, estimation of the results of psychological techniques. The data suggest that personality deficits play a more significant role in the social maladaptation of patients with SD than cognitive impairment.

Olfaction, "olfiction," and the schizophrenia-spectrum: an updated meta-analysis on identification and acuity

Olfaction deficits in individuals with schizophrenia are well documented. A meta-analysis conducted nearly a dozen years ago on the topic revealed a deficit of a full standard deviation in magnitude compared to nonpatient controls. Recent efforts have been attempted to determine whether deficits in olfactory identification and acuity reflect a vulnerability marker of schizophrenia-spectrum pathology. To address this issue, the present study conducted a meta-analysis of 16 studies of individuals with schizotypy, defined in terms of a) "ultra-high risk" status, b) having an affected biological family member, or c) having extreme scores on a schizotypy questionnaire. We also conducted an updated meta-analysis of 40 studies of olfactory functioning in schizophrenia. Consistent with the prior meta-analysis, patients with schizophrenia showed impairments in olfaction identification on a full standard deviation in magnitude (d = -.99). Individuals with schizotypy showed much more subtle (d = -.24) differences in olfaction, though the effect sizes were higher for studies examining individuals at "ultra-high risk" (d = -.67) versus studies examining individuals with psychometrically-defined (d = -.14) schizotypy. Differences in olfactory acuity, relative to their respective control groups, were small for both the schizophrenia (d = -.45) and schizotypy (d = -.38) studies but were similar in magnitude. The present findings argue against the notion that deficits in olfaction identification are a vulnerability marker of schizophrenia. Suggestions for future research are recommended.

Predictive smooth eye pursuit in a population of young men: II. Effects of schizotypy, anxiety and depression

Smooth pursuit eye movement dysfunction is considered to be a valid schizophrenia endophenotype. Recent studies have tried to refine the phenotype in order to identify the specific neurophysiological deficits associated with schizophrenia. We used a variation of the smooth eye pursuit paradigm, during which the moving target is occluded for a short period of time and subjects are asked to continue tracking. This is designed to isolate the predictive processes that drive the extraretinal signal, a process previously reported to be defective in schizophrenia patients as well as their healthy relatives. In the current study, we investigated the relationship between predictive pursuit performance indices and age, education, non-verbal IQ, schizotypy and state anxiety, depression in 795 young Greek military conscripts. State anxiety was related to better predictive pursuit performance (increase in residual pursuit gain), while disorganized schizotypy was related to deficient predictive pursuit performance (decreased residual gain). This effect was independent of the effect of disorganized schizotypy on other oculomotor functions supporting the hypothesis that predictive pursuit might be specifically affected in schizophrenia spectrum disorders and could be considered as a distinct oculomotor endophenotype.

Outcome of severe obsessive-compulsive disorder with schizotypal features: a pilot study

BACKGROUND/PURPOSE

Long-term outcome of patients with severe obsessive-compulsive disorder (OCD) and schizotypal features has been rarely studied. We investigated this issue in this retrospective pilot study.

METHODS

Twenty-two patients with severe OCD and schizotypal features were identified by chart review. Another 22 OCD patients without schizotypal features (OCD-NS) served as the comparison group. Those with schizotypal features must not fulfill a diagnosis of schizophrenia or schizotypal disorder. After an average follow-up of 6.6 years, each patient received a re-diagnosis clinical interview. Relevant demographic and clinical data were collected. Patients with schizotypal features were classified into two groups after re-diagnosis: those with schizophrenia or schizotypal disorder (OCD-SS group, n = 9) and those with only schizotypal traits (OCD-ST group, n = 13) that did not fulfill a well-formed schizophrenia-spectrum disorder. Demographic data, family history, clinical symptoms, and OCD course were compared among the three patient groups.

RESULTS

Compared with the OCD-NS group, the OCD-SS group was significantly less educated, less likely to be married or female, and had earlier onset of illness and poorer OCD course (p<0.05). There was no significant difference in any demographic and clinical variables between the OCD-SS and OCD-ST groups except that the OCD-ST group had a significantly better OCD course (p < 0.01).

CONCLUSION

The findings suggest that a substantial proportion of the patients with severe OCD and schizotypal features evolve into schizophrenia spectrum disorder and are associated with a poor long-term outcome, whereas the OCD-NS group might stay with limited manifestations of schizotypal features and have a better outcome.

Overlap of autistic and schizotypal traits in adolescents with Autism Spectrum Disorders

This study addresses the unraveling of the relationship between autism spectrum and schizophrenia spectrum traits in a population of adolescents with Autism Spectrum Disorders (ASD). Recent studies comparing isolated symptoms of both spectrum disorders as well as diagnostic criteria for each (DSM-IV-TR) suggest resemblances in the clinical phenotype. A group of 27 adolescents with ASD (11 to 18 years) and 30 typically developing adolescents, matched for age and gender, participated in this study. Within the ASD group 11 adolescents satisfied DSM-IV-TR criteria for schizotypal personality disorders. Autistic and schizotypal traits were identified by means of well validated questionnaires (Autism Questionnaire, AQ and Schizotypal Personality Questionnaire-Revised, SPQ). Significantly more schizotypal traits in adolescents with ASD were found than in typically developing controls. Besides high levels of negative symptoms, adolescents with ASD also displayed high levels of positive and disorganized symptoms. There appeared to be a relationship between the mean level of autistic symptoms and schizotypal traits, as well as specific associations between autistic symptoms and negative, disorganized and positive schizotypal symptoms within individuals. Schizotypal symptomatology in all sub dimensions that are reflected by the SPQ scores, was most prominently associated with attention switching problems of the autism symptoms from the AQ. These findings indicate that patients diagnosed with an ASD show schizophrenia spectrum traits in adolescence. Although other studies have provided empirical support for this overlap in diagnostic criteria between both spectrum disorders, the present findings add to the literature that behavioral overlap is not limited to negative schizotypal symptoms, but extends to disorganized and positive symptoms as well.

Schizotypy and altered digit ratios: a second look

Alterations in the ratio between the 2nd and 4th finger digits have been posited as a potential indicator of increased liability for neurodevelopmental disorders such as autism and schizophrenia. We compared digit ratios in two groups of psychometrically-identified schizotypes, namely, those characterized by positive schizotypy (perceptual aberrations and magical ideation; n=76) and those characterized by negative schizotypy (social anhedonia; n=64), to a control group (n=110). The groups were also compared in terms of their performance on a measure of Theory of Mind, namely, the Reading the Mind in the Eyes Test (RMET) and trait affect, as measured by the PANAS. Our results indicate that neither negative schizotypy nor positive schizotypy is associated with altered digit ratios. Similarly, the groups showed no significant differences on the RMET. However, we observed a small but significant inverse association between Theory of Mind performance and negative affect. The findings are considered in light of the extant literature. These results call into question the viability of altered digit ratios to serve as an indicator of increased risk for schizophrenia-spectrum disorders.

Affective reactivity of speech disturbances in schizotypy

Speech disturbances (SD) are a pernicious symptom of schizophrenia that increase when negative emotion is elicited. This increase is referred to as affective reactivity (AR). Although considerable research has examined SD in schizophrenia, few studies have investigated this symptom in individuals at risk for the disorder, who demonstrate schizophrenia-like, or schizotypic, traits. In the present study, we examined: (1) SD severity in schizotypy, (2) how SD varies as a function of stress reactivity in schizotypy, and (3) the relationship between SD/AR with Quality of Life (QOL). Individuals with psychometrically-defined schizotypy (n=83) and controls (n=22) completed a laboratory procedure in which they produced speech while viewing pleasant and stressful photographs. This speech was analyzed for subtle speech disorder using a well-validated measure. We found that the schizotypy group demonstrated significant increases in SD across both baseline and stressful conditions compared to the control group. AR was not significantly different between the groups. Within the schizotypy group, severity of disorganized schizotypy symptoms was associated with high levels of SD and AR while interpersonal schizotypy was associated with low levels of SD and AR. AR was also related to increased objective QOL in the schizotypy group. This study highlights the role of stress reactivity across the schizophrenia-spectrum. Moreover, the incongruous relationships between disorganized and interpersonal symptoms with SD underscore the marked heterogeneity in processes across schizotypy.

Schizotypy and false memory

Using the Deese-Roediger-McDermott (DRM) paradigm the present study examined the relationship between schizotypy and recognition memory. Participants scoring in the upper and lower quartile ranges for schizotypy (Schizotypal Personality Questionnaire brief version; SPQ-B) and on each of the SPQ-B subscales (cognitive-perceptual, interpersonal and disorganized) were compared on true and false memory performance. Participants scoring in the lower quartile range on the cognitive-perceptual subscale recognised a higher proportion of both true and false memories than those scoring in the higher quartile range. Participants scoring in the upper quartile on the interpersonal factor recognised fewer true items than those in the lower quartile range. No differences were found for overall schizotypy or on the disorganized subscale.

[Compressive-spectral analysis of EEG in patients with panic attacks in the context of different psychiatric diseases]

Panic disorders (PD) which develop in the context of different psychiatric diseases (neurotic, personality disorder and schizotypal disorders) have their own clinical and neurophysiological features. The results of compressive-spectral analysis of EEG (CSA EEG) in patients with panic attack were different depending on the specifics of initial psychiatric status. EEG parameters in patients differed from those in controls. The common feature for all PD patients was the lower spectral density of theta-, alpha- and beta-bands as well as total spectral density without any alterations of region distribution. The decrease of electrical activity of activation systems was found in the groups with neurotic and schizotypal disorders and that of inhibition systems - in the group with schizotypal disorders. The EEG results did not suggest any depression of activation systems in patients with specific personality disorders. The data obtained with CSA EEG mirror the integrative brain activity which determinad of the appearance of PA as well as of nosology of psychiatre disease.

Anorexia nervosa with chronic episodes for more than 30 years in a patient with a comorbid schizotypal personality disorder

Schizotypal personality disorder (SPD) has rarely been reported as an eating disorder-related personality trait. A 23-year-old woman was diagnosed as having anorexia nervosa binge eating/purging type. At the age of 53 years, she was admitted to Jikei University Hospital because of excessive bodyweight loss. She was diagnosed as having SPD based on bizarre behavior, ideation and a tendency to seek isolation. She was treated with low-dose antipsychotics, and her impulsive behavior improved. The patient's SPD was considered to have had a psychopathological contribution to her chronic episodes of anorexia nervosa.

Traductions françaises et validations des échelles de dérapage cognitif (Cognitive Slippage Scale, Miers et Raulin, 1987) et d’ambivalence schizotypique (Schizotypal Ambivalence Scale, Raulin, 1986)

AIMS

The aim of this article is firstly to present the French translations of the Cognitive Slippage (Miers and Raulin, 1987) and the Schizotypal Ambivalence Scales (Raulin, 1986), and secondly to determine their psychometric properties in different samples of non-clinical and clinical subjects.

BACKGROUND

Chapman et al. have developed trait-oriented scales based on Meehl's manual of schizotypy, such as the Physical and Social Anhedonia Scales, the Perceptual Aberration Scale, the Magical Ideation Scale, the Impulsive Nonconformity Scale, the Cognitive Slippage Scale (CSS), and the Schizotypal Ambivalence Scale (SAS). The Chapman scales of psychosis proneness are the most internationally used instruments for the assessment of schizotypy and some of them such as the Cognitive Slippage and Schizotypal Ambivalence Scales were still not available in French.

METHOD

The study was conducted in three different samples: the non-clinical sample (n=158) comprised firstly 128 university students (113 females, 15 males) with a mean age of 24.67 years (sd=5.18) and secondly 30 healthy subjects (12 males, 18 females) with a mean age of 33.26 years (sd=7.35); the clinical sample (n=167) comprised firstly 106 psychiatric patients hospitalized in a general hospital (73 males, 33 females) with a mean age of 38.35 years (sd=11.60) and 61 (35 males, 26 females) in or outpatients of a psychiatric department with a mean age of 37.75 years (sd=10.72); 15 schizotypal university students presenting high score of the Revised Social Anhedonia Scale (1 male, 14 females) with a mean age of 21.26 years (sd=1.1). Using the ICD-10, the diagnoses for the general hospital sample were neurotic or anxious disorders (47%) and depressive disorders (24%). For the psychiatric department sample, the diagnoses were schizophrenic disorders (29%), mood disorders (16%), neurotic disorders (18%) and personality disorders (15%). The internal consistency was determined by the Kuder-Richardson coefficient (KR 20) (CSS: KR 20=0.85 in the university sample; 0.89 in the general hospital sample; 0.87 in the psychiatric department sample; SAS: KR 20=0.79 in the university sample; 0.82 in the general hospital sample; 0.85 in the psychiatric department sample).

RESULTS

The mean of the correlations between each item and the total score was calculated (CSS: 0.41 in the university sample; 0.44 in the general hospital sample; SAS: 0.46 in the university sample; 0.49 in the general hospital sample). The discriminant validity was studied by a Student's t test showing that the schizotypal university students had significant higher scores on the CSS and SAS than the healthy university students. The reliability was explored using a test-retest in the 30 healthy subjects. The subjects filled out the scales three months after the first testing. The intraclass coefficients were 0.81. Finally, the cutoff scores were calculated following the procedure described by Chapman et al. (score higher than two standard deviations above the mean of the university sample). The values for the CSS and SAS were respectively 15 and 12 for males and females.

Comparison of three computer-administered cognitive tasks as putative endophenotypes of schizophrenia

It has been repeatedly demonstrated that individuals with schizotypal personality features (SPF) exhibit similar endophenotypic traits as persons with schizophrenia. Less research has compared the relative sensitivity of different endophenotypes in the same sample of individuals with SPF. Fourteen university students with SPF (mean age 20.5+/-1.6; 43% male) and 26 controls (mean age 20.3+/-1.1; 31% male) were defined by the Abbreviated Schizotypal Personality Questionnaire (SPQ-B). All participants reported no known biological relative with schizophrenia. Participants completed three computer-administered cognitive tasks: a 6-min degraded-stimuli A-X Continuous Performance Test (CPT), the Wisconsin Card Sort Test (WCST), and a Span of Apprehension (SOA) task (6- and 12-letter arrays). On the CPT, only omission errors resulted in a statistically significant group difference, U=115.5, p=.05, Cohen's d=0.54 (medium effect size), with the SPF group (mean errors: 3.43+/-3.28) making more omission errors than controls (mean errors: 1.88+/-2.66). Notably, 46% of the controls had no omission errors, compared to 14% of the SPF group. The only SPQ-B factor score to show a statistically significant linear relationship with CPT omission errors was the Cognitive-Perceptual factor (rs=.33, p=.04). Group differences on performance indices from the SOA and WCST did not approach statistical significance. Based on performance from the community-identified schizotypes, results suggest that performance on the CPT may represent a more robust endophenotype of schizophrenia, compared to the SOA and WCST.

Self-face recognition and theory of mind in patients with schizophrenia and first-degree relatives

OBJECTIVE

The hypothesized relationship between theory of mind (ToM) and self-face recognition as well as its potential genetic associations has not been previously explored in patients with schizophrenia and in first-degree relatives with schizotypal personality traits.

METHOD

Ten patients diagnosed with schizophrenia, 10 of their first-degree relatives and 10 healthy controls were included. To assess self-face recognition (SFR), participants were presented images of faces of themselves and others and asked to make rapid 'unfamiliar', 'familiar' and 'self' judgments. As a measure of ToM, subjects were administered the Revised Mind in the Eyes Test (MET [Baron-Cohen, S., Wheelwright, S., Hill, J., Raste, Y., and Plumb, I., 2001. The "Reading the Mind in the Eyes" Test revised version: a study with normal adults, and adults with Asperger syndrome or high-functioning autism. J Child Psychol Psychiatry 42(2), 241-251.]). Schizotypal characteristics in relatives and controls were assessed using a modified version of the Schizotypal Personality Questionnaire (SPQ [Raine, A., 1991. The SPQ: a scale for the assessment of schizotypal personality based on DSM-III-R criteria. Schizophrenia Bulletin 17(4), 555-564.]).

RESULTS

Patients took longer and were less accurate on the SFR task than their relatives who in turn performed worse than healthy controls. Specific ToM deficits in schizophrenia were replicated. There was a relationship between accuracy rates on the MET and SFR tasks. High levels of schizotypal traits such as social anxiety, constricted affect and no close friends were important for both tasks.

CONCLUSIONS

Face recognition deficits and ToM deficits in schizophrenia are apparent. The critical influence of high levels of select schizotypal traits is also highlighted. A deficit in relatives of schizophrenia patients raises the possibility that ToM and face recognition deficits may be candidate endophenotypes for schizophrenia. Support for the hypothesized link between ToM and face recognition is provided.

Smooth pursuit eye movements in 1,087 men: effects of schizotypy, anxiety, and depression

Individuals with schizotypal personality disorder or high scores in questionnaires measuring schizotypy are at high risk for the development of schizophrenia and they also share some of the same phenotypic characteristics such as eye-tracking dysfunction (ETD). The question arises whether these individuals form a distinct high-risk group in the general population or whether schizotypy and ETD co-vary in the general population with no distinct cutoff point for a high-risk group. A large sample of military conscripts aged 18-25 were screened using oculomotor, cognitive and psychometric tools for the purposes of a prospective study on predisposing factors for the development of psychosis. Schizotypy measured using the perceptual aberration scale (PAS) and the schizotypal personality questionnaire (SPQ), anxiety and depression, measured using the Symptom Checklist 90-R, had no effect on pursuit performance in the total sample. Small groups of individuals with very high scores in schizotypy questionnaires were then identified. These groups were not mutually exclusive. The high PAS group had higher root-mean-square error scores (a quantitative measure for pursuit quality) than the total sample, and the high disorganized factor of SPQ group had lower gain and higher saccade frequencies in pursuit than the total sample. The presence of significant differences in pursuit performance only for predefined high schizotypy groups favors the hypothesis that individuals with high schizotypy might present one or more high-risk groups, distinct from the general population, that are prone to ETD as that observed in schizophrenia.

Impairment of memory organization in patients with schizophrenia or schizotypal disorder

Verbal learning and the organization of memory in patients with schizophrenia or schizotypal disorder were compared with normal subjects. Three indices of memory organization (semantic clustering, serial clustering, and subjective clustering) were calculated from participants' responses on the Japanese Verbal Learning Test. Schizophrenic and schizotypal patients showed similar decrements in semantic organization compared with normal subjects. Neither patient group showed any effect of learning on their use of semantic organization, although both groups recalled more items as the number of trials increased. These results suggest that impairment of memory organization is a common characteristic of schizophrenia spectrum disorders.

Gray matter volume reduction in obsessive-compulsive disorder with schizotypal personality trait

OBJECTIVES

Obsessive-compulsive disorder (OCD) with schizotypal personality trait (SPT) and OCD without SPT demonstrated differences in cognitive dysfunction and treatment response. This study aimed to investigate whether brain volume differs between OCD with SPT and OCD without SPT.

METHODS

OCD with SPT (n=20), OCD without SPT (n=47), healthy comparison subjects (n=83) and schizophrenic patients (n=59) participated in this study. We assessed brain volume such as gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) using magnetic resonance imaging. The imaging data sets were filtered using anisotropic diffusion methods to improve the signal to noise ratio. The semi-automated region-growing method was used to remove images of tissues exterior to the brain. The fuzzy C-means algorithm was used to segment the extracted brain images into gray matter, white matter and cerebrospinal fluid.

RESULTS

OCD with SPT (p=0.048) and Schizophrenic patients (p<0.001) demonstrated a significant GM volume reduction compared to healthy controls. OCD without SPT revealed no significant GM volume reduction compared to healthy controls (p=0.504).

CONCLUSION

This study suggests that OCD with SPT could be distinguished as a distinct subtype of OCD, based on observations of gray matter volume.

Anxiety and depression symptoms in psychometrically identified schizotypy

The neurodevelopmental vulnerability for schizophrenia appears to be expressed across a dynamic continuum of adjustment referred to as schizotypy. This model suggests that nonpsychotic schizotypic individuals should exhibit mild and transient forms of symptoms seen in full-blown schizophrenia. Given that depression and anxiety are reported to be comorbid with schizophrenia, the present study examined the relationship of psychometrically defined schizotypy with symptoms of depression and anxiety in a college student sample (n=1258). A series of confirmatory factor analyses indicated that a three-factor solution of positive schizotypy, negative schizotypy, and negative affect provided the best solution for self-report measures of schizotypy, anxiety, and depression. As hypothesized, the model indicated that symptoms of depression and anxiety are more strongly associated with the positive-symptom dimension of schizotypy than with the negative-symptom dimension. This is consistent with studies of schizophrenic patients and longitudinal findings that positive-symptom schizotypes are at risk for both mood and non-mood psychotic disorders, while negative-symptom schizotypes appear more specifically at risk for schizophrenia-spectrum disorders.

Theory of mind and its relation to schizotypy

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Verbal creativity and schizotypal personality in relation to prefrontal hemispheric laterality: a behavioral and near-infrared optical imaging study

Although anecdotal and correlational results have suggested a reliable relationship between creativity and psychosis, few studies have examined this relationship using empirical methods. In addition, little is known about the neural substrates of creative thinking. We investigated the creative thinking process in relation to schizotypal personality, schizophrenia and prefrontal hemispheric laterality using behavioral and near-infrared optical spectroscopy (NIRS) methods. Schizophrenic, psychometrically ascertained schizotypal, and healthy control subjects (all right-handed) participated in a novel "alternate uses" task designed to assess divergent thinking (DT) ability. The DT task required subjects to generate "uses" for conventional and ambiguous objects. Prefrontal activity was measured using NIRS while subjects were engaged in DT vs. a cognitive control task in a subset of the subjects. Behavioral data indicated that schizotypes had enhanced DT ability compared with schizophrenic and control subjects, who showed similar performance overall. NIRS data showed that DT was associated with bilateral prefrontal cortex (PFC) activation, but the right PFC particularly contributed to the enhanced creative thinking in psychometric schizotypes compared with the other two groups. Thus, creative thinking seems to robustly recruit bilateral PFC, but it is the right PFC that is preferentially activated in schizotypes in relation to their enhanced DT.

Reduced anterior and posterior cingulate gray matter in borderline personality disorder

BACKGROUND

Structural abnormalities in prefrontal and cingulate gyrus regions-important in affective processing, impulse control and cognition may contribute to the psychopathology of borderline personality disorder (BPD). Previous MRI studies examining volume have reported that compared with healthy controls, BPD patients have decreases in right anterior cingulate, no differences in dorsolateral prefrontal cortex, and mixed findings for prefrontal cortex. We extended this investigation by examining gray and white matter volume of frontal and cingulate gyrus Brodmann areas (BAs) in a large group of patients and healthy controls.

METHODS

MRI scans were acquired in 50 BPD patients (n = 13 with comorbid diagnosis of BPD and Schizotypal Personality Disorder (SPD) and n = 37 without SPD) and 50 healthy controls, and gray/white matter volume in cingulate gyrus and frontal lobe BAs were assessed. Normal BPD and BPD subgroup comparisons were conducted.

RESULTS

Compared with controls, BPD patients showed reduced gray matter volume in BA 24 and 31 of the cingulate. BPD patients without comorbid SPD had isolated gray matter volume loss in BA 24, but were spared for BA 31 in contrast to BPD patients with SPD. There were no group differences in whole cingulate or frontal lobe volume.

CONCLUSIONS

The finding of more pervasive cingulate shrinkage in the patients with BPD and SPD comorbidity resembles recent observations with the same methods in patients with schizophrenia. The pattern of reduced anterior and posterior cingulate gray matter volume in BPD patients, particularly those comorbid for SPD is consistent with the affective and attentional deficits observed in these personality disorders.

Obsessive-compulsive disorder (OCD) with schizotypy vs. schizophrenia with OCD: diagnostic dilemmas and therapeutic implications

Although schizophrenia and obsessive-compulsive disorder (OCD) are distinct diagnostic entities, there are substantial areas of overlap between the two disorders in clinical characteristics, affected brain areas and pharmacotherapy. Though OCD patients apparently do not have increased risk for developing schizophrenia, schizotypal personality disorder has consistently been found in OCD patients. Compelling evidence also points to an increased rate of OCD in schizophrenia patients. Accurate diagnosis of both disorders in their "pure" and overlapping forms is necessary in order to evaluate etiological mechanisms underlying schizophrenia and OCD, and to provide adequate treatment and prognosis. In this review, we address some aspects of the current status of research pertinent to the OCD-schizophrenia interface and suggest further steps towards the clinical and etiological identification of homogeneous subgroups on the putative OCD-schizophrenia axis.

Thought–action fusion and its relationship to schizotypy and OCD symptoms

Thought-action fusion (TAF) is a cognitive bias that has been linked to obsessive-compulsive disorder (OCD). Preliminary evidence suggests schizotypal traits may be associated with some types of OCD obsessions but not others. We examined the relationship between each of the two major types of TAF (i.e., likelihood and moral), schizotypal traits, and OCD symptoms in 969 nonclinical undergraduate students. We hypothesized that likelihood TAF would be associated with schizotypal traits; whereas moral TAF would not. Consistent with prediction, schizotypal-magical thinking was significantly associated with likelihood TAF even after controlling for the effects of OCD symptoms, general anxiety, and depression. Moreover, the relationship between likelihood TAF and OCD symptoms was significantly attenuated after controlling for schizotypal traits. In contrast, moral TAF demonstrated negligible association with OCD symptoms, depression, or schizotypal traits. These findings provide preliminary support for the linkage between likelihood TAF and schizotypal traits.

Schizotypy and conditional reasoning

This study investigated the role of reasoning biases in delusion formation and maintenance. Reasoning judgments have been shown to be influenced by prior knowledge, beliefs, and experience--that is, information stored in semantic memory. It was hypothesized that high schizotypes would exhibit a "jump to conclusions" style of reasoning as a result of not using implicit information concerned with cause-effect relationships. Research into human reasoning has traditionally adopted logic as a normative framework to assess human reasoning. Conditional inference tasks are direct tests of logical performance, and we employed an established design that depends upon the reasoner's ability to access and use implicit information. In an effort to negate some of the difficulties of research with schizophrenia patients, schizotypy measures were employed in a normal population. The results confirmed that high scorers on one dimension of schizotypy (Impulsive Nonconformity) failed to take account of the number of counterexamples that characterized the cause-effect conditional statement. These observations supported previous research demonstrating a jump to conclusions style of reasoning that it has been suggested plays a role in the formation and maintenance of delusions. Furthermore, these findings suggest a possible link between semantic memory and reasoning biases.

Positive schizotypal symptoms predict treatment outcome in obsessive-compulsive disorder

Previous research has suggested that the presence of schizotypal personality disorder may represent a risk factor for treatment failure in obsessive-compulsive disorder (OCD). Relying on a dimensional approach, the present study investigated whether the predictive importance of schizotypal personality is shared by all of its features to the same extent or whether it is confined to a subset of symptoms. Fifty-three patients underwent multi-modal cognitive-behavioral therapy with or without adjunctive antidepressive medication. Therapy response was defined as a 35% decline of the Y-BOCS total score. At baseline assessment, patients were asked to fill out the schizotypal personality questionnaire, the perceptual aberration scale and the Beck depression inventory. Stepwise regression analysis and group comparisons conducted with the schizotypal and depression scales revealed that elevated scores in the positive schizotypal scales, especially perceptual aberrations, were highly predictive for treatment failure. Responders to treatment and non-responders did not significantly differ on other variables or on scores in two scales which measured response biases. The study provides evidence that positive schizotypal symptoms are antecendents for treatment failure in OCD. It needs to be evaluated whether these at-risk individuals benefit from additional intervention, such as the adminstration of low-dose atypical neuroleptics and specifically tailored behavorial intervention.

Neuromotor functioning in adolescents with schizotypal personality disorder: associations with symptoms and neurocognition

Previously, Neumann and Walker (1999) used a computerized motor assessment and found that adults with schizotypal personality disorder (SPD) displayed increased and more variable motor force compared to adults with other personality disorders or healthy controls. Using the same motor assessment, the current study examined whether an independent sample of adolescents with SPD manifested a similar pattern of motor dysfunction compared to adolescents with other Axis II disorders or those without a disorder. As predicted, the SPD group showed increased and more variable force compared to the other two groups, which did not differ on these measures. These same motor variables were correlated with negative symptoms, as well as perseverative responses on a card sorting test. The significant correlations between motor functioning and perseverative responses and negative symptoms support recent research suggesting that subcortical motor regions play a role in higher order cognition and negative symptoms. Differences as well as broad similarities in the pattern of motor findings between the adult and adolescent SPD studies are discussed.

Context-Processing Deficits in Schizotypal Personality Disorder

Research suggests that schizotypal personality disorder (SPD) is a part of the spectrum of schizophrenia-related illnesses. This article hypothesizes that a deficit in the representation and maintenance of context is a core cognitive disturbance in schizophrenia and that SPD individuals should demonstrate context-processing deficits. To test this hypothesis, the authors administered 3 versions of their AX-CPT task, designed to assess context processing, to 35 healthy controls and 26 individuals with DSM-IV SPD. They also administered working memory and selective attention tasks. SPD individuals displayed context representation deficits similar to those found in schizophrenia but did not show the same additional deficits in context maintenance. Context processing was strongly associated with working memory and selective attention performance in the SPD individuals.

Executive function assessed by memory updating and random generation in schizotypal individuals

Individuals scoring high (N=32) and low (N=27) on the unusual experiences (UnEx) scale of the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) were selected from a large sample (N=265) of normal volunteer undergraduates. The high- and low-UnEx groups were compared on two tasks, random generation and memory updating, which target executive functions that inhibit prepotent responses and update current information. The groups differed only on the R measure of random generation that assesses inequality in the relative frequencies of response alternatives, a result attributed to superstitious behaviour rather than to executive deficit. The results suggest that the executive impairments previously observed in high schizotypal individuals using the Wisconsin Card Sorting Test and other measures are selective rather than global.

Neuropsychological function in obsessive-compulsive disorder: effects of comorbid conditions on task performance

BACKGROUND

Neuropsychological testing reveals a pattern of impairment among patients with obsessive-compulsive disorder (OCD) which implicates the orbitofrontal region. Studies of neuropsychological function in OCD differ regarding performance deficits on classical tests of frontal executive function. In some studies, OCD patients did not demonstrate impaired performance on tests of executive function. However, other researchers have documented performance deficits among OCD patients on measures of executive function. Patients with OCD also exhibit performance deficits on tests of visual/spatial memory and verbal memory. Again, in some studies, OCD patients did not demonstrate impaired performance on tests of memory function. How can we account for the conflicting findings? One possibility is that performance deficits on tests of cognitive function are associated with comorbid conditions. In prior work, we observed that OCD patients who did poorly on executive function tasks obtained high scores on a measure of schizotypal personality. A second possibility is that executive function deficits among patients with OCD are associated with comorbid depressive symptoms.

METHOD

In the present study, a comprehensive neuropsychological test battery was administered to patients with OCD and matched healthy control subjects. We also administered dimensional measures of schizotypal personality and depression to patients with OCD and controls. We conducted analyses of covariance (ANCOVA), with scores on measures of schizotypal personality and depression used as covariates.

RESULTS

OCD patients demonstrated performance deficits on measures of delayed memory, response inhibition, alternation learning, and obtained significantly higher scores on measures of disinhibition, impulsivity, and temporolimbic symptoms; however, OCD patients did not exhibit impaired performance on tests of executive function and verbal fluency, and did not report a significantly greater number of dysexecutive symptoms, when coexistent depressive and schizotypal symptoms were taken into account.

CONCLUSION

Findings are consistent with the contention that dysfunction of an orbitofrontal-limbic network underlies OCD.

[Clinical characteristics of patients with slow progressive schizophrenia combined with alcoholism]

Fifty-eight patients with slow progressive schizophrenia combined with alcoholism have been examined. Different variants of affective pathology described determined an alcohol addiction in patients with slow progressive schizophrenia. According to the structure of affective disorders and related types of excessive drinking, 3 groups of patients were identified. Group 1 was characterized by negative affection with detachment, continuous (progressive) type of alcoholism course and constant type of alcohol use; group 2 was characterized by positive affection with undulatory course of alcoholism and alcohol use, pseudo-drinking-bout type. Group 3 was distinguished by positive affection with distinct timing of disorder appearance, periodic course of alcoholism and spontaneous form of alcohol drinking. The most unfavorable prognosis was for group 1 and favorable one--for group 3.