Positive and negative symptoms of schizophrenia: past, present, and future

Unveiling altered connectivity between cognitive networks and cerebellum in schizophrenia

Cognitive functioning is a crucial aspect in schizophrenia (SZ), and when altered it has devastating effects on patients' quality of life and treatment outcomes. Several studies suggested that they could result from altered communication between the cortex and cerebellum. However, the neural correlates underlying these impairments have not been identified. In this study, we investigated resting state functional connectivity (rsFC) in SZ patients, by considering the interactions between cortical networks supporting cognition and cerebellum. In addition, we investigated the relationship between SZ patients' rsFC and their symptoms. We used fMRI data from 74 SZ patients and 74 matched healthy controls (HC) downloaded from the publicly available database SchizConnect. We implemented a seed-based connectivity approach to identify altered functional connections between specific cortical networks and cerebellum. We considered ten commonly studied resting state networks, whose functioning encompasses specific cognitive functions, and the cerebellum, whose involvement in supporting cognition has been recently identified. We then explored the relationship between altered rsFC values and Positive and Negative Syndrome Scale (PANSS) scores. The SZ group showed increased connectivity values compared with HC group for cortical networks involved in attentive processes, which were also linked to PANSS items describing attention and language-related processing. We also showed decreased connectivity between cerebellar regions, and increased connectivity between them and attentive networks, suggesting the contribution of cerebellum to attentive and affective deficits. In conclusion, our findings highlighted the link between negative symptoms in SZ and altered connectivity within the cerebellum and between the same and cortical networks supporting cognition.

Patient Perspectives on AI-Driven Predictions of Schizophrenia Relapses: Understanding Concerns and Opportunities for Self-Care and Treatment

Early detection and intervention for relapse is important in the treatment of schizophrenia spectrum disorders. Researchers have developed AI models to predict relapse from patient-contributed data like social media. However, these models face challenges, including misalignment with practice and ethical issues related to transparency, accountability, and potential harm. Furthermore, how patients who have recovered from schizophrenia view these AI models has been underexplored. To address this gap, we first conducted semi-structured interviews with 28 patients and reflexive thematic analysis, which revealed a disconnect between AI predictions and patient experience, and the importance of the social aspect of relapse detection. In response, we developed a prototype that used patients' Facebook data to predict relapse. Feedback from seven patients highlighted the potential for AI to foster collaboration between patients and their support systems, and to encourage self-reflection. Our work provides insights into human-AI interaction and suggests ways to empower people with schizophrenia.

The positive dimension of schizotypy is associated with self-report measures of autobiographical memory and future thinking but not experimenter-scored indices

ABSTRACTThe ability to remember our past and to imagine the future are critical to our sense of self. Previous research has indicated that they are disrupted in schizophrenia. However, it is unclear (i) whether this is found when examining experimenter-scored indices of content and/or participants' self-report of phenomenological characteristics, and (ii) how these abilities might be related to symptoms. This study sought to address these questions by taking a dimensional approach and measuring positive and negative schizotypal experiences in healthy people (n = 90). Participants were given cue words. For some, they remembered an event from the past and for others they generated an event in the future. No significant relationships were found with any aspect of schizotypy when participants' descriptions were scored by the experimenter according to a standardised episodic content measure. In contrast, several significant positive correlations were observed for past memory and future thinking when examining the positive dimension of schizotypy and participants' ratings, particularly to sensory characteristics of the experience and mental pre- or reliving. These results indicate enhanced subjective experiences of autobiographical memory and future thinking in those who report delusional and hallucinatory-like occurrences, which might be linked to mental imagery or metacognitive alterations.

Mutual information of multiple rhythms in schizophrenia

Interactions between different cortical rhythms, such as slow and fast oscillations, have been hypothesized to underlie many cognitive functions. In patients diagnosed with schizophrenia, there is some evidence indicating that the interplay between slow and fast oscillations might be impaired or disrupted. In this study, we investigated multiple oscillatory interactions in schizophrenia using a novel approach based on information theory. This method allowed us to investigate interactions from a new perspective, where two or more rhythm interactions could be analyzed at the same time. We calculated the mutual information of multiple rhythms (MIMR) for EEG segments registered in resting state. Following previous studies, we focused on rhythm interactions between theta, alpha, and gamma. The results showed that, in general, MIMR was higher in patients than in controls for alpha-gamma and theta-gamma couplings. This finding of an increased coupling between slow and fast rhythms in schizophrenia may indicate complex interactions in the Default Mode Network (DMN) related to hyperactivation of internally guided cognition.

Proverb comprehension in schizophrenia: A comprehensive review and meta-analysis.2

BACKGROUND

Examination of proverb comprehension has a long tradition in clinical diagnostics of individuals with schizophrenia (iSCZ). Deficits in the comprehension are considered common. Interpretations of proverbs are traditionally measured by their degree of abstraction and concreteness ('literalness'), but iSCZ's responses may also be illogical or 'bizarre'. Experimental research on proverb comprehension starts in the 1940s. Since then, the specificity of proverb tests has often been questioned, but has never been the subject of a meta-analysis. The aim of this meta-analysis is to include all experimental research, including historical studies, that meets quality criteria and compares the responses to proverbs in iSCZ with those in healthy controls (HC) or clinical controls (CC).

METHODS

PubMed, Web of Science, and PsycInfo databases were searched. After coding 121 articles, 27 (median publication year 1982) were included and multi-level meta-analyses performed. Moderator analyses were performed on response format (multiple-choice vs. verbal responses), proverb test, scoring method, language, acute vs. chronic stage of iSCZ, time of publication, clinical vs. healthy control group, age, IQ/education, and gender. Publication bias was assessed using funnel plots, trim and fill method and Egger's test.

RESULTS

The search identified 27 eligible studies for inclusion. Studies were published between 1956 and 2020 and predominantly older than 30 years (median: 1982). The Gorham Proverbs Test was the most established test and predominantly conducted in English. CC mostly consisted of depressive disorders. Pooled estimates yielded statistically significant less abstract (g = -1.00; 95%CI, -1.34 to -1.67), more concrete (g = 0.69; 95%CI, 0.35-1.03), and more bizarre (g = 1.08; 95%CI, 0.74-1.41) responses in iSCZ compared to controls. The type of control group moderated all three effects, with greater differences of iSCZ compared to HC than to CC in abstraction and bizarreness, and no significant group difference between iSCZ and CC in concreteness. Meta-regressions indicated IQ/education and age as possible sources of variability in abstraction and bizarreness.

CONCLUSIONS

While lower abstraction and higher bizarreness seems a characteristic of iSCZ, the diagnostic specificity of a concrete response was astonishingly low. The lack of a unified definition for concretism and limited consideration of cultural diversity contributed to these complex findings. Future research should focus on exploring the qualitative aspects of proverb comprehension and the association between symptomatology types and misinterpretations to improve diagnostic accuracy.

Is there an affective neuroscience of spirituality? The development and validation of the OCEANic feelings scale

Background

Oceanic feelings represent a phenomenological structure of affective sensations that characteristically involve feelings of self-dissolution and feelings of unity and transcendence. This study presents the preliminary version of a self-report instrument to measure individual dispositions toward oceanic feelings in order to enable further research within the concept of primary emotions postulated by Jaak Panksepp.

Methods

A first version of the questionnaire was applied to a total sample of 926 German-speaking adults of the general population. After performing item analysis and principal component analysis (PCA) in a first study (N = 300), the questionnaire was shortened. In a second study (N = 626), confirmatory factor analysis (CFA) was conducted and emerged scales were related to the already established instruments for the assessment of primary emotions (BANPS-GL) and Big Five personality traits (BFI-44).

Results

The OCEANic scale exhibited reliabilities ranging from Cronbach's α = 0.82 (positive) to α = 0.88 (negative) and plausible correlations with behavioral traits related to the seven affective neurobiological systems (ANGER, FEAR, CARE, SEEK, PLAY, SADNESS, and LUST) as well as with personality factors measured by the Big Five Inventory. For CFA, a bifactorial model with an overall factor demonstrated good fit: RMSEA = 0.00 (90% CI:0.00, 0.03); TLI = 1.00; CFI = 1.00; NFI = 0.99.

Discussion

The OCEANic scale enables the operationalization of oceanic feelings comprising two subscales and one total scale. The results indicate good reliability and acceptable factorial validity. Establishment and further validation of the OCEANic scale within future research will be needed to fully understand the role of oceanic feelings within the human affective life, especially the personality trait of spirituality.

Time will tell: Associations between unbalanced time perspectives and symptom severity in individuals with schizophrenia spectrum disorders

Patients with schizophrenia spectrum disorder (SSD) experience disrupted temporality on the immediate timescale. However, insufficient information is available for longer time frames, and the interaction of temporal perspectives with the clinical manifestations of SSD is unknown. We explored the association between unbalanced time perspectives and symptom severity. Thirty-seven Italian mental health services participating in the DiAPAson project recruited 620 patients with DSM-5 SSD (68 % males, mean age = 41.3 ± 9.5 years). Time perspective biases were measured using the Deviation from the Balanced Time Perspective-revisited (DBTP-r) indicator, based on Zimbardo Time Perspective Inventory (ZTPI) scores. Psychiatric symptoms were assessed using the Brief Psychiatric Rating Scale (BPRS) and Brief Negative Symptoms Scale (BNSS). Preliminary analyses examined the associations between ZTPI/DBTP-r and BPRS/BNSS total scores. In secondary analyses, we first tested the associations between the ZTPI/DBTP-r and BPRS/BNSS subscales and then compared ZTPI differences between patients with and without hallucinations, delusions, and conceptual disorganisation. Statistical significance was set at Holm-Bonferroni corrected p < 0.05. Low-to-moderate positive correlations were found between the DBTP-r and BPRS/BNSS total scores (r = 0.29/0.22). The strongest associations were between DBTP-r/ZTPI_Past-Negative and anxiety/depression (r = 0.34/0.36), followed by DBTP-r/ZTPI_Present-Fatalistic with thought disturbances (r = 0.22/0.20). DBTP-r was associated with BNSS anhedonia and avolition (r = 0.21/0.24). DBTP-r was higher in patients with hallucinations (ES = 0.391) and conceptual disorganisation (ES = 0.397) than in those without these symptoms. Unbalanced time perspective was positively associated with the severity of primary and secondary SSD features. These findings provide a rationale for empirical tests focused on balancing time perspectives in patients with SSD.

Sexual Dysfunction in Schizophrenia: A Narrative Review of the Mechanisms and Clinical Considerations

Psychiatric disorders, in general, have a high prevalence of sexual problems, whether from the psychopathology of the disorder itself, pre-existing or co-morbid sexual disorder or from side effects of the treatment for mental disorders. Many patients report an already existing sexual dysfunction at the onset of diagnosis. The risk association for developing sexual dysfunction in patients with schizophrenia includes antipsychotic use and resulting hyperprolactinemia, age, gender, and disease severity. Medication side effects lead to nonadherence, and relapses lead to structural changes in the brain, treatment resistance, and worsening of symptoms. Findings in certain studies propose serum prolactin and thyroid-stimulating hormone measurement as a tool for assessing patients with schizophrenia for sexual dysfunction. Regarding specific symptoms, females especially reported decreased desire at baseline and galactorrhea after treatment. The findings of this review, therefore, suggest that sexual dysfunction may be present in patients with schizophrenia before starting antipsychotic treatment and that patients, especially those who are female, are likely to develop hyperprolactinemia with antipsychotic treatment. Aripiprazole may be an emergent treatment for sexual dysfunction in those who use antipsychotics. It is important for patients to consider sexual dysfunction prior to prescribing antipsychotics. Since sexual dysfunction can impact a patient’s quality of life and affect treatment adherence, it is important for physicians to be aware and monitor patients for symptoms.

Longitudinal stability of cognitive control in early psychosis: Nondegenerative deficits across diagnoses

Cognitive impairment, particularly in the domain of cognitive control, is characteristic of schizophrenia (SZ) spectrum and bipolar disorders (BDs). The longitudinal trajectory of these impairments, however, remains unclear. Indeed, some studies have observed degeneration and others stability or even improvement over time in these illnesses. Here we examined the longitudinal stability of the AX-Continuous Performance Task (AX-CPT), a cognitive control task, in 52 patients with recent-onset SZ (<2 years from first study measurement), 20 patients with recent-onset BD Type I with psychotic features, and 70 healthy control subjects. Subjects performed the AX-CPT at 2 time points separated by an average of 365 days (range 270-620). Previously identified deficits in cognitive control were replicated in both patient groups. No effects of time or interactions between time and diagnosis were observed. Intraclass correlation coefficients also suggested AX-CPT performance was stable across time for all diagnostic groups. Although performance was stable on average, a positive association was noted between change in cognitive control and change in disorganization symptom severity across patient groups. In conclusion, the present findings suggest that deficits in cognitive control are present in both disorders and stable over the early course of psychotic illness. No evidence was observed for progression or deterioration of cognitive control or differential recovery in SZ compared to BD. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Effects of intranasal oxytocin on symptoms of schizophrenia: A multivariate Bayesian meta-analysis

Schizophrenia is a heterogeneous disorder in which psychiatric symptoms are classified into two general subgroups-positive and negative symptoms. Current antipsychotic drugs are effective for treating positive symptoms, whereas negative symptoms are less responsive. Since the neuropeptide oxytocin (OT) has been shown to mediate social behavior in animals and humans, it has been used as an experimental therapeutic for treating schizophrenia and in particular negative symptoms which includes social deficits. Through eight randomized controlled trials (RCTs) and three meta-analyses, evidence for an effect of intranasal OT (IN-OT) has been inconsistent. We therefore conducted an updated meta-analysis that offers several advantages when compared to those done previously: (1) We used a multivariate analysis which allows for comparisons between symptoms and accounts for correlations between symptoms; (2) We controlled for baseline scores; (3) We used a fully Bayesian framework that allows for assessment of evidence in favor of the null hypothesis using Bayes factors; and (4) We addressed inconsistencies in the primary studies and previous meta-analyses. Eight RCTs (n=238) were included in the present study and we found that oxytocin did not improve any aspect of symptomology in schizophrenic patients and there was moderate evidence in favor of the null (no effect of oxytocin) for negative symptoms. Multivariate comparisons between symptom types revealed that oxytocin was not especially beneficial for treating negative symptoms. The effect size estimates were not moderated, publication bias was absent, and our estimates were robust to sensitivity analyses. These results suggest that IN-OT is not an effective therapeutic for schizophrenia.

[Use of antidepressants in the treatment of negative symptoms of schizophrenia]

Negative symptoms account for a clinical dimension of schizophrenia. They are partly the cause of functional disability of this disease. Clinical experience shows that antipsychotics have little or no effect on these symptoms. The aim of this review is to gather existing data on the treatment of negative symptoms with antidepressants. The combination of antipsychotics with antidepressants is a therapeutic strategy commonly used for the treatment of these symptoms. The pro-dopaminergic effects of antidepressants explain their effectiveness on negative symptoms. There are many comparative, randomized, controlled studies evaluating the efficacy of antidepressant associated with antipsychotic for the treatment of negative symptoms. Furthermore three meta-analyses have been conducted. The overall results suggest that the use of antidepressants may contribute to clinical improvement of negative symptoms in schizophrenia. The limitations of these studies are the small number of patients included and the definition and assessment of negative symptoms. The existing scales are not sufficiently discriminating. Further research using new measurement tools should help refine these results.

Development of a staff training intervention for inpatient mental health rehabilitation units to increase service users’ engagement in activities

Introduction

This study developed a training intervention (‘GetREAL’) to change the practice of staff working in National Health Service inpatient mental health rehabilitation units in order to increase service users’ engagement in activities.

Method

The intervention was developed through eight consultation events and piloting in two settings, drawing on the expertise of occupational therapists, psychiatrists, organisational change specialists and service users, together with multi-disciplinary teams.

Results

A manual for the intervention, a fidelity checklist, an induction programme and training materials were produced. The intervention applied a three-stage change model (predisposing, enabling and reinforcing) and was informed by theories from occupational therapy and organisational development. It was delivered by psychiatrists, occupational therapists, activity workers and service users. Staff were encouraged to change their ward structures and routines as well as their practice. Clinical supervision and reflective practice were integral to the trainers’ regime.

Conclusion

The intervention was theoretically coherent, allied to practice and shown to be feasible to deliver. It offered tailored work-based training to the whole multi-disciplinary team, including support staff. Making activity central to rehabilitation could improve patients’ use of time and their consequent function and wellbeing. However, questions were raised about long-term sustainability of change processes.

Abnormal emotion processing, but intact fairness and intentionality considerations during social decision-making in schizophrenia

Schizophrenia is a severe mental disorder that is highly characterized by social cognitive impairments. Most studies investigating these impairments focus on one specific social domain such as emotion recognition. However, in daily life, processing complex social situations relies on the combination of several social cognitive and affective processes simultaneously rather than one process alone. A modified version of the economically based Ultimatum Game was used to measure the interplay between fairness, intentionality, and emotion considerations during social decision-making. In this task, participants accept or reject fair and unfair monetary offers proposed intentionally or unintentionally by either angry, happy, neutral, or sad proposers. Behavioral data was collected from a group of schizophrenia patients (N = 35) and a group of healthy individuals (N = 30). Like healthy participants, schizophrenia patients differentiated between fair and unfair offers by rejecting unfair offers more compared to fair offers. However, overall patients did reject more fair offers, indicating that their construct of fairness operates within different margins. In both groups, intentional unfair offers were rejected more compared to unintentional ones, indicating a normal integration of intentionality considerations in schizophrenia. Importantly, healthy subjects also differentiated between proposers' emotion when rejecting unfair offers (more rejections from proposers depicting angry faces compared to proposers depicting, happy, neutral, or sad faces). Schizophrenia patients' decision behavior on the other hand, was not affected by the proposers' emotions. The current study thus shows that schizophrenia patients have specific problems with processing and integrating emotional information. Importantly, the finding that patients display normal fairness and intentionality considerations emphasizes preservation of central social cognitive processes in schizophrenia.

The nature of the relationship of psychomotor slowing with negative symptomatology in schizophrenia

INTRODUCTION

Psychomotor slowing is an important feature of schizophrenia and the relation with negative symptoms is not fully understood. This study aims, first, to investigate the association between negative symptoms and psychomotor slowing. Second, we want to investigate whether fine motor slowing reflects clinically observable gross motor slowing.

METHODS

In 53 stabilised adult patients with schizophrenia, negative symptoms were assessed using the Positive and Negative Syndrome Scale negative subscale (PANSS-N) with two calculated factors entering the analysis: an expressivity factor and a volitional factor. Psychomotor slowing was assessed by using a modified version of the Salpêtrière Retardation Rating Scale, the Finger Tapping Test, and a writing task measuring fine psychomotor slowing.

RESULTS

Negative symptomatology is associated with difficulties in the initiation of fine motor movements, r=.334, p<.05, whilst planning and execution are not. The volitional factor, r=-.407, p=.005, but not the expressivity factor, r=.060, p=.689, is significantly associated with psychomotor slowing. No associations between fine and clinically observable gross psychomotor functioning were found.

CONCLUSIONS

These findings indicate that higher values of negative symptomatology-more specifically the volitional deficit cluster-affect motor initiation, indicating a heterogeneity in the PANSS-N factorial structure, and that gross and fine psychomotor functioning are affected independently.

Abnormal cerebellar structure is dependent on phenotype of isolated cleft of the lip and/or palate

Isolated cleft lip and/or palate (ICLP) is one of the most common congenital birth defects in the USA, affecting roughly 1 in 600 births annually. Along with the facial deformity, this population has been found to have abnormal neurodevelopment and gross structural abnormalities in the brain, particularly within the cerebellum. The current study examined cerebellar structure within the two primary subtypes of ICLP: cleft lip with/without cleft palate (CL/P) and cleft palate alone (CPO). A large sample of 107 subjects aged 7 to 27 years with ICLP was compared to 127 healthy controls. Samples were separated by sex. Brain structure was obtained via magnetic resonance imaging. For males, after controlling for intracranial volume, cerebellum volume was significantly lower in the ICLP group (F = 12.351, p = 0.001). Regionally in the cerebellum, males with ICLP had proportionally larger anterior lobes (F = 4.022, p = 0.047) and smaller superior posterior lobes (F = 5.686, p = 0.019). CL/P males showed only a reduction in overall cerebellum volume, with no regional changes. CPO males showed only regional changes, with no reduction in overall volume. Females with ICLP showed no overall or regional cerebellar abnormalities. However, females with CPO did have significantly lower cerebellum volumes than controls. The results reveal both global and regional cerebellar abnormalities within subjects with ICLP. They also establish the existence of abnormal cerebellar morphologies that are dependent on cleft subtype as well as sex. This lends further support to the claim that CL/P and CPO are distinct conditions.

Factor structure of the targeted inventory on problems in schizophrenia

Objective

The aim of this study was to explore the factor structure of a novel, 10-item rating scale, the Targeted Inventory on Problems in Schizophrenia (TIP-Sz). Determining the factor structure will be useful in the brief evaluation of medication and non-medication treatment of the disease.

Methods

An exploratory factor analysis was performed on TIP-Sz scores obtained from 100 patients who met the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria for schizophrenia.

Results

The factor analysis extracted four factors that were deemed clinically pertinent, which we labeled: disorganization, social cooperativeness, functional capacity, and emotional state. The items exhibited cross-loadings on the first three factors (i.e., some items loaded on more than one factor). In particular, the 'behavioral dyscontrol and disorganization,' 'insight and reality testing,' and 'overall prognostic impression' items had comparable cross-loadings on all of the first three factors. The emotional state factor was distinct from the other factors in that the items loading on it did not cross-load on other factors.

Conclusion

The TIP-Sz scale comprises factors that are associated with the psychosocial functioning and emotional state of patients, which are important outcome parameters for successful treatment of the disease.

Current visual scanpath research: a review of investigations into the psychotic, anxiety, and mood disorders

The human visual system is comprised of an array of complex organs, which jointly decode information from visible light to construct a meaningful representation of the surrounding environment. The study of visual scanpaths transpired in a bid to enhance our understanding of the role of eye movements underpinning adaptive functioning as well as psychopathology and was further aided by the advent of modern eye-tracking techniques. This review provides a background to the nature of visual scanpaths, followed by an overview and critique of eye movement studies in specific clinical populations involving the psychotic, anxiety, and mood disorders, and concludes with suggested directions for future research. We performed a Medline and PsycInfo literature search, based on variations of the terms "visual scanpath," "eye-tracking," and "eye movements," in relation to articles published from 1986 to the present. Eye-tracking studies in schizophrenia mostly concurred with the existence of a "restricted" scanning strategy, characterized by fewer number of fixations of increased durations, with shorter scanpath lengths, and a marked avoidance of salient features, especially in relation to facial emotion perception. This has been interpreted as likely reflecting dual impairments in configural processing as well as gestalt perception. Findings from the anxiety and mood disorders have conversely failed to yield coherent results, with further research warranted to provide corroborating evidence and overcome identified methodological limitations. Future studies should also look toward applying similar techniques to related disorders as well as conducting parallel neuroimaging investigations to elucidate potential neurobiological correlates.

Recovery of behavioral changes and compromised white matter in C57BL/6 mice exposed to cuprizone: effects of antipsychotic drugs

Recent animal and human studies have suggested that the cuprizone (CPZ, a copper chelator)-fed C57BL/6 mouse may be used as an animal model of schizophrenia. The goals of this study were to see the recovery processes of CPZ-induced behavioral changes and damaged white matter and to examine possible effects of antipsychotic drugs on the recovery processes. Mice were fed a CPZ-containing diet for 5 weeks then returned to normal food for 3 weeks, during which period mice were treated with different antipsychotic drugs. Various behaviors were measured at the end of CPZ-feeding phase as well as on the 14th and 21st days after CPZ withdrawal. The damage to and recovery status of white matter in the brains of mice were examined. Dietary CPZ resulted in white matter damage and behavioral abnormalities in the elevated plus-maze (EPM), social interaction (SI), and Y-maze test. EPM performance recovered to normal range within 2 weeks after CPZ withdrawal. Alterations in SI showed no recovery. Antipsychotics did not alter animals’ behavior in either of these tests during the recovery period. Altered performance in the Y-maze showed some recovery in the vehicle group; atypical antipsychotics, but not haloperidol, significantly promoted this recovery process. The recovery of damaged white matter was incomplete during the recovery period. None of the drugs significantly promoted the recovery of damaged white matter. These results suggest that CPZ-induced white matter damage and SI deficit may be resistant to the antipsychotic treatment employed in this study. They are in good accordance with the clinical observations that positive symptoms in schizophrenic patients respond well to antipsychotic drugs while social dysfunction is usually intractable.

The contribution of epidemiology to defining the most appropriate approach to genetic research on schizophrenia

Psychosis is thought to have a strong genetic component, but many efforts to discover the underlying putative schizophrenia genes have yielded disappointing results. In fact, no strong associations emerged in the first genome-wide association studies in psychiatry and weakly observed associations were not related to the candidate genes identified in previous studies. These partially successful findings may be explained by the fact that genetic research in psychiatry suffers from confounding issues related to phenotype definition, the considerable degree of phenotypic variability and diagnostic uncertainty, absence of specific neuropathological features and environmental influences. To make progress it is first necessary to deconstruct psychosis based on symptomatology, and then to correlate particular phenotypes with genetic variants. Moreover, it is time to conduct studies that define persistent aspects of the schizophrenic profile that are more likely to represent an underlying biological pathogenesis, as opposed to fluctuating symptoms that are possibly environmentally mediated. In fact, progress in understanding the etiology of schizophrenia will depend upon the availability of good measures of genetic liability as well as relevant environmental exposures during critical periods of an individual's life. If environmental and/or genetic factors are not precisely measured, it is impossible to study their independent effects or interactions.

Variability of plasma homovanillic acid over 13 months in patients with schizophrenia; relationship with the clinical response and the Wisconsin card sort test

In the present study we have measured, on a monthly basis, the concentration of plasma homovanillic acid (pHVA) in schizophrenic patients during 13 months of their pharmacological treatment. The average pHVA values of each patient were within the range of 7.30-17.70 ng/ml and the coefficients of variation for each patient (CV %) were within the range of 13-33%. Half of the patients that showed higher pHVA CV% values also showed higher scores on the Brief Psychiatric Rating Scale at the beginning of the study, and improved more after 6 months, when compared to the remaining 50% with lower CV% values. There was no significant relationship between the scores of the Wisconsin Card Sort Test and the concentration or the CV% of the pHVA of each patient. A greater variability in the pHVA may be associated with a greater plasticity of the dopaminergic system and a better clinical response.

Cerebellum structure differences and relationship to speech in boys and girls with nonsyndromic cleft of the lip and/or palate

OBJECTIVE

To identify regional cerebellar structural differences in boys and girls with nonsyndromic cleft of the lip and/or palate and determine whether these differences are related to speech impairment.

DESIGN

Between 2003 and 2007, measures on cerebellar volume were obtained on 43 children with nonsyndromic cleft of the lip and/or palate and 43 age- and sex-matched, healthy controls. Children with the cleft condition also received speech evaluations. Children with nonsyndromic cleft of the lip and/or palate were recruited from clinic records, and controls (screened for medical, psychiatric, speech/language, and behavioral concerns) were recruited from the local community. All tests were administered at a large midwestern hospital. Boys and girls with nonsyndromic cleft of the lip and/or palate were compared with the healthy controls on global and regional measures of cerebellar volume. Areas of significant difference were then correlated with measures of speech to assess relationships in children with nonsyndromic cleft of the lip and/or palate.

RESULTS

Boys with nonsyndromic cleft of the lip and/or palate had smaller cerebellums than controls (p = .002); whereas, for girls, only regional reductions in size reached significance (corpus medullare, p = .040). Cerebellum size was correlated with articulation for boys (p = .045).

CONCLUSIONS

These findings lend support to previous research documenting abnormal brain structure in children with nonsyndromic cleft of the lip and/or palate and suggest that the cerebellum may play a role in speech deficits along with other structural causes, at least in boys.

The functional neuroanatomy of symptom dimensions in schizophrenia: a qualitative and quantitative review of a persistent question

One of the fundamental goals in understanding schizophrenia is linking the observable symptoms to the underlying unobservable pathophysiology. Given recent advances in medical imaging, researchers are increasingly investigating brain-behavior relationships to better understand the neural substrates of negative, positive, and disorganization symptoms in schizophrenia. This review focused on 25 task-related functional magnetic resonance imaging studies and found meaningful small to moderate associations between specific symptom dimensions and regional brain activity. Negative symptoms were related to the functioning of the ventrolateral prefrontal cortex and ventral striatum. Positive symptoms, particularly persecutory ideation, were related to functioning of the medial prefrontal cortex, amygdala, and hippocampus/parahippocampal region. Disorganization symptoms, although less frequently evaluated, were related to functioning of the dorsolateral prefrontal cortex. Surprisingly, no symptom domain had a consistent relationship with the middle or superior temporal regions. While a number of adaptations in experimental design and reporting standards can facilitate this work, current neuroimaging approaches appear to provide a number of consistent links between the manifest symptoms of schizophrenia and brain dysfunction.

Neurocognitive mechanisms of conceptual processing in healthy adults and patients with schizophrenia

This overview outlines findings of cognitive and neurocognitive studies on comprehension of verbal, pictorial, and video stimuli in healthy participants and patients with schizophrenia. We present evidence for a distinction between two complementary neurocognitive streams of conceptual analysis during comprehension. In familiar situations, adequate understanding of events may be achieved by mapping the perceived information on the associative and similarity-based connections between concepts in semantic memory - a process reflected by an N400 waveform of event-related electrophysiological potentials (ERPs). However, in less conventional contexts, a more flexible mechanism may be needed. We suggest that this alternative processing stream, reflected by a P600 ERP waveform, may use discrete, rule-like goal-related requirements of real-world actions to comprehend relationships between perceived people, objects, and actions. This neurocognitive model of comprehension is used as a basis in discussing studies in schizophrenia. These studies suggest an imbalanced engagement of the two conceptual streams in schizophrenia, whereby patients may rely on the associative and similarity-based networks in semantic memory even when it would be more adaptive to recruit mechanisms that draw upon goal-related requirements. Finally, we consider the roles that these conceptual mechanisms may play in real-life behavior, and the consequences that their dysfunction may have for disorganized behavior and inability to plan actions to achieve behavioral goals in schizophrenia.

What we know: findings that every theory of schizophrenia should explain

The article summarizes the process used to distill schizophrenia science into 22 facts. These facts consist of 6 basic facts, 3 etiological facts, 6 pharmacological and treatment facts, 5 pathology facts, and 2 behavioral facts that were critically reviewed by the scholarly community through a special initiative in cooperation with the Schizophrenia Research Forum. A subset of 10 of these facts was selected to form a common set of findings to be explained from the different theoretical perspectives included in this special section of Schizophrenia Bulletin. The rationale for this exercise is to distinguish more precisely the areas of agreement and disagreement between theories of schizophrenia and to highlight where more thought and data can make the greatest impact for understanding this disease.

Serotonergic dysfunction in the prodromal, first-episode and chronic course of schizophrenia as assessed by the loudness dependence of auditory evoked activity

Recent studies revealing evidence of increased serotonergic neurotransmission in schizophrenia has generated substantial interest in the role of serotonin in its pathophysiology. None of these studies, however, have queried whether dysfunctional serotonergic activity might already have been present in subjects of at-risk mental state for schizophrenia before the onset of psychotic symptoms, and whether serotonergic activity further increases during the development of schizophrenia and the chronic course. Although no valid indicator for measuring the activity level of serotonergic neurotransmission has yet been found, a series of evidence from human and animal studies suggests that a weak loudness dependence of auditory evoked potentials (LDAEP) indicates high serotonergic activity and vice versa. We examined the LDAEP (N1/P2 component) in 60 patients with at-risk mental state for schizophrenia who showed characteristic prodromal symptoms, 34 first-episode patients, 28 patients with a chronic course of schizophrenia and 57 healthy controls. Prodromal patients showed significantly weaker LDAEP in comparison to healthy volunteers, but similarly to that in first-episode and chronic patients. None of the covariates such as age, gender, medication, age of onset, or psychopathology had an influence on this finding. In a subsample of prodromal patients, LDAEP values remain the same after retesting 10 months later. These results indicate that serotonergic neurotransmission had already increased before the onset of the full-blown psychosis of schizophrenia and remains enhanced in the further course of the disease. A weak LDAEP may therefore represent a vulnerability marker rather than an expression of illness progression.

Multifunctional pharmacotherapy: what can we learn from study of selective serotonin reuptake inhibitor augmentation of antipsychotics in negative-symptom schizophrenia?

Many patients suffering from major psychiatric disorders do not respond adequately to monotherapy and require additional drugs. To date, there are no objective guidelines for deciding which combination may be effective, and the choice is based on previous clinical experience and on trial and error. Even when combination drugs are effective, the biochemical mechanisms responsible for the value-added effect are unknown. Understanding the mechanism of such synergism may provide a rational basis for choosing drug combinations and for developing more effective drugs. In schizophrenia, negative symptoms respond poorly to antipsychotics, but may improve when these are augmented with selective serotonin reuptake inhibitors (SSRI). This augmenting effect cannot be explained by summating the pharmacological effects of the individual drugs. We proposed that the study of SSRI augmentation can serve as a window to understanding the biochemical mechanisms of clinically effective drug synergism. In a series of studies we identified unique biochemical effects of the combination, different from each individual drug, and proposed that some of these are involved in mediating the clinical effect. Here we review some of the findings and propose that the mechanism of action involves regionally selective modulation of the GABA system. The evidence indicates that the SSRI antidepressant-antipsychotic combination may be a useful paradigm for studying therapeutically effective synergistic drug interactions in schizophrenia. Although as yet limited in scope, the findings of definable molecular targets for synergistic SSRI-antipsychotic interaction provide new directions to inform future research and provide novel bio-molecular targets for drug development.

8-Chloro-5-(4-phenethylpiperazin-1--yl)pyrido[2,3-b][1,5]benzoxazepine

As part of an anti-psychotic drug discovery program, we report the crystal structure of the title compound, C(24)H(23)ClN(4)O. The mol-ecule has a tricyclic framework with a characteristic buckled V-shaped pyridobenzoxazepine unit, with the central seven-membered heterocycle in a boat configuration. The piperazine ring displays a chair conformation with the 2-phenyl-ethyl substituent assuming an equatorial orientation. There are two crystallographically independent, but virtually identical, mol-ecules in the asymmetric unit.

Neural correlates of trust

Trust is a critical social process that helps us to cooperate with others and is present to some degree in all human interaction. However, the underlying brain mechanisms of conditional and unconditional trust in social reciprocal exchange are still obscure. Here, we used hyperfunctional magnetic resonance imaging, in which two strangers interacted online with one another in a sequential reciprocal trust game while their brains were simultaneously scanned. By designing a nonanonymous, alternating multiround game, trust became bidirectional, and we were able to quantify partnership building and maintenance. Using within- and between-brain analyses, an examination of functional brain activity supports the hypothesis that the preferential activation of different neuronal systems implements these two trust strategies. We show that the paracingulate cortex is critically involved in building a trust relationship by inferring another person's intentions to predict subsequent behavior. This more recently evolved brain region can be differently engaged to interact with more primitive neural systems in maintaining conditional and unconditional trust in a partnership. Conditional trust selectively activated the ventral tegmental area, a region linked to the evaluation of expected and realized reward, whereas unconditional trust selectively activated the septal area, a region linked to social attachment behavior. The interplay of these neural systems supports reciprocal exchange that operates beyond the immediate spheres of kinship, one of the distinguishing features of the human species.

An entropy-based approach for testing genetic epistasis underlying complex diseases

The genetic basis of complex diseases is expected to be highly heterogeneous, with complex interactions among multiple disease loci and environment factors. Due to the multi-dimensional property of interactions among large number of genetic loci, efficient statistical approach has not been well developed to handle the high-order epistatic complexity. In this article, we introduce a new approach for testing genetic epistasis in multiple loci using an entropy-based statistic for a case-only design. The entropy-based statistic asymptotically follows a chi(2) distribution. Computer simulations show that the entropy-based approach has better control of type I error and higher power compared to the standard chi(2) test. Motivated by a schizophrenia data set, we propose a method for measuring and testing the relative entropy of a clinical phenotype, through which one can test the contribution or interaction of multiple disease loci to a clinical phenotype. A sequential forward selection procedure is proposed to construct a genetic interaction network which is illustrated through a tree-based diagram. The network information clearly shows the relative importance of a set of genetic loci on a clinical phenotype. To show the utility of the new entropy-based approach, it is applied to analyze two real data sets, a schizophrenia data set and a published malaria data set. Our approach provides a fast and testable framework for genetic epistasis study in a case-only design.

Evidence of an inferior total-order planning strategy in patients with frontotemporal dementia

We investigated planning abilities in patients with frontal temporal dementia (FTD) and normal controls (NC) using a chore location planning task. Planning tasks with increasing complexity could be either solved by constructing a linear total plan (total-order planning) or partially ordered sub-plans (partial-order planning). The NC group appeared to use partial-order planning, while the FTD group appeared to use total-order planning based on error pattern in performance, task-solution, and planning time. Our results are a reminder that besides social impairments, FTD patients also demonstrate higher-order cognitive impairment in domains such as planning and that these impairments may also have a profound effect upon the patients' day-to-day functioning.

Subjective organisation in the free recall learning of adults with Asperger's syndrome

Single trial methods reveal unimpaired free recall of unrelated words in Asperger's syndrome (AS). When repeated trials are used (free recall learning), typical individuals show improved recall over trials, subjective organisation of material (SO) and a correlation between free recall and SO. We tested oral (Experiment 1) and written (Experiment 2) free recall over 16 trials in adults with AS and typical individuals. Across both experiments AS participants showed marginally diminished recall. Poorer SO was seen in the Asperger group only in Experiment 2, but in both experiments, individual differences in SO in the Asperger group were less likely to converge over trials. This lack of convergence suggests that the AS group organise material in idiosyncratic ways.

Impairment in event sequencing in disorganised and non-disorganised patients with schizophrenia

It has been suggested that thought disorder in schizophrenia is associated with impaired executive functions and with a defective understanding of others' behaviour. Action sequence knowledge processing and goal detection are considered as crucial components of executive functioning. Here, we used a picture-sequencing task to assess the ability of schizophrenic patients (n = 40) with and without disorganisation symptoms to arrange different types of action sequence representations. Disorganisation symptoms appear to be associated with a general sequencing impairment, while patients without disorganisation symptoms displayed difficulties in ordering sequences requiring subjects to infer mental states in story characters along with a relatively preserved performance in correctly arranging mechanical or behavioural event sequences. These results reveal that only schizophrenic patients without disorganisation symptoms show a selective deficit in mentalising abilities whereas disorganisation symptoms are associated with a more severe event sequencing impairment probably reflecting basic failures of inferential reasoning.

[Wiscosin card sorting task in patients with schizophrenia and thier siblings]

OBJECTIVE

This study's first objective was to confirm that patients with schizophrenia and their nonmentally ill siblings share the same impaired executive function when compared to healthy control subjects. The second objective was to study the relation between Wisconsin card sorting task (WCST) performance and the persistence and severity of clinical symptoms, as well as different clinical dimensions.

METHOD

Ninety subjects were involved in this study, divided in 3 groups of 30 each: one group of patients with schizophrenia, one group of their siblings, and a control group. Symptom severity was assessed with the Positive and Negative Syndrome Scale (PANSS), and social functioning was measured by the Global functioning scale (GFS). The WCST was administered to all 3 groups.

RESULTS

Patients with schizophrenia and their siblings had a significantly lower WCST performance than control subjects. Statistical analysis showed that the patient group had a significantly greater impaired WCST performance than the 2 other groups. Siblings also had a significantly lower performance than the control subjects. Furthermore, no significant relation was found between WCST performance and other variables, including age, gender, education, illness duration, treatment, and different PANSS and GFS scores.

CONCLUSION

Patients with schizophrenia and their nonmentally ill siblings share the same impaired executive function. These findings suggest that WCST performance can be considered a schizophrenia vulnerability marker in siblings of patients with schizophrenia.

The Positive and Negative Symptoms Questionnaire: a self-report scale in schizophrenia

The assessment of various symptoms in schizophrenia has received much interest, although few studies have compared evaluations by clinicians to those of their patients. Self-report tools may improve service delivery, data collection, and possibly also treatment adherence. We constructed the Positive and Negative Symptoms Questionnaire (PNS-Q), a self-report measure, after items from the Scale for Assessment of Positive Symptoms (SAPS) and the Scale for Assessment of Negative Symptoms (SANS). The PNS-Q contained 68 items and was administered to 61 schizophrenic inpatients. We examined its psychometric properties and utility as a self-report tool in schizophrenia. The PNS-Q exhibited high internal consistency for both its positive and negative subscales. External validity with the SAPS and SANS was low. The positive symptoms subscale correlated significantly with the SAPS ( r = .341, P < .01), whereas the negative symptoms subscale did not correlate at all with the SANS ( r = -0.086, P > .1). The correlation between patients' insight and scores of the PNS-Q was mixed. A partial correlation analysis failed to confirm a relationship between the rating of the patients' level of insight (measured by the Amador Scale to Assess Unawareness of Mental Disorders [SUMD]) and the disparity between the PNS-Q and the SAPS and SANS. However, the PNS-Q correlated highly with McEvoy's Vignettes, a measure of self-perception of symptoms. The results of this study are discussed in light of current research and methodologic issues. The PNS-Q reflects schizophrenics' self-perception, an important, yet neglected, aspect of schizophrenia. Using this new measure, we believe that clinicians and researchers will be able to gain insight to the inner world of these patients and improve their condition, as well as enhance patients' involvement in treatment planning.

Regulation of affect by the lateral septum: implications for neuropsychiatry

Substantial evidence indicates that the lateral septum (LS) plays a critical role in regulating processes related to mood and motivation. This review presents findings from the basic neuroscience literature and from some clinically oriented research, drawing from behavioral, neuroanatomical, electrophysiological, and molecular studies in support of such a role, and articulates models and hypotheses intended to advance our understanding of these functions. Neuroanatomically, the LS is connected with numerous regions known to regulate affect, such as the hippocampus, amygdala, and hypothalamus. Through its connections with the mesocorticolimbic dopamine system, the LS regulates motivation, both by stimulating the activity of midbrain dopamine neurons and regulating the consequences of this activity on the ventral striatum. Evidence that LS function could impact processes related to schizophrenia and other psychotic spectrum disorders, such as alterations in LS function following administration of antipsychotics and psychotomimetics in animals, will also be presented. The LS can also diminish or enable fear responding when its neural activity is stimulated or inhibited, respectively, perhaps through its projections to the hypothalamus. It also regulates behavioral manifestations of depression, with antidepressants stimulating the activity of LS neurons, and depression-like phenotypes corresponding to blunted activity of LS neurons; serotonin likely plays a key role in modulating these functions by influencing the responsiveness of the LS to hippocampal input. In conclusion, a better understanding of the LS may provide important and useful information in the pursuit of better treatments for a wide range of psychiatric conditions typified by disregulation of affective functions.

Comparison of neurocognition between drug-free patients with schizophrenia and bipolar disorder

It is often difficult to make a differential diagnosis between schizophrenia and bipolar disorder because of the overlapping symptoms. The patients of both disorders have been shown to have neurocognitive deficits. In this study, a computerized battery of neurocognitive tasks, COGLAB, was administered to four participant groups: 30 patients with positive schizophrenia, 22 patients with negative schizophrenia, 27 patients with bipolar disorder, and 28 normal controls. All the patients were drug-free for at least 1 month. The tasks included Mueller-Lyer illusion, reaction time, size estimation, a variant of the Wisconsin Card Sorting Test, backward masking, and Asarnow continuous performance. Discriminant analyses were used to investigate the differences among the four groups. Results indicated that COGLAB correctly classified 73.5% of the cases of negative schizophrenia and bipolar disorder. The best discriminative tasks were card sort, Asarnow continuous performance, and backward masking. The results of this study were also compared with results of a previous study with medicated patients. Neurocognitive tasks had better discriminative power for medicated patients with schizophrenia and bipolar disorder than for drug-free patients. Moreover, medication effects did not seem to significantly change the pattern of the neurocognitive task responses of patients with schizophrenia.

Association study of an SNP combination pattern in the dopaminergic pathway in paranoid schizophrenia: a novel strategy for complex disorders

Schizophrenia is a common mental disorder with a complex pattern of inheritance. Despite a large number of studies in the past decades, its molecular etiology remains unknown. In this study, we proposed a 'system-thinking' strategy in seeking the combined effect of susceptibility genes for a complex disorder by using paranoid schizophrenia as an example. We genotyped 85 reported single-nucleotide polymorphisms (SNPs) present in 23 genes for the dopamine (DA) metabolism pathway among 83 paranoid schizophrenics and 108 normal controls with detailed clinical and genetic information. We developed two novel multilocus approaches-the potential effective SNP combination pattern and potential effective dynamic effects analysis, by which three susceptibility genotype combinations were found to be associated with schizophrenia. These results were also validated in a family-based cohort consisting of 95 family trios of paranoid schizophrenia. The present findings suggest that the COMT and ALDH3 combination may be the most common type involved in predisposing to schizophrenia. Since the combination blocks the whole pathways for the breakdown of DA and noradrenaline, it is very likely to play a central role in developing paranoid schizophrenia.

Differential regulation of hippocampal BDNF mRNA by typical and atypical antipsychotic administration

Apart from their differential propensities to block dopamine D2 and serotonin 5-HT2 receptors, the molecular mechanisms underlying the clinical efficacy of typical and atypical antipsychotics in schizophrenia are largely unknown. Given recent interest in the effects of antipsychotics on neurotrophic and other growth related factors, the effects of antipsychotics on brain-derived neurotrophic factor (BDNF), a neurotrophin crucial to the structural integrity of adult neurons, were investigated in male Wistar rats. Chronic (19 day) but not acute (45 min) antipsychotic administration significantly altered levels of hippocampal BDNF mRNA. In addition, whereas chronic treatment with the strong D2 receptor-blocker haloperidol significantly downregulated hippocampal BDNF mRNA, the selective 5-HT2 receptor-blocker ritanserin significantly upregulated CA1 hippocampal BDNF mRNA in comparison to controls. Since high doses of risperidone and clozapine produce potent inhibition of both 5-HT2 and D2 receptors, while lower doses produce significantly greater 5-HT2 vs. D2 receptor blockade, a dose-response study was employed to determine whether low doses of these atypical antipsychotics would also upregulate hippocampal BDNF mRNA in the absence of significant D2 receptor blockade. Whereas chronic haloperidol and high-dose risperidone significantly downregulated hippocampal BDNF mRNA, intermediate and lower doses of risperidone and clozapine were, unlike ritanserin, without effect when compared to controls. Thus, although the long-term downregulation of hippocampal BDNF mRNA may underlie the different clinical profiles of certain antipsychotics, this effect seems to be associated with antipsychotic doses that not only cause significant D2 receptor inhibition, but are usually associated with side effects rather than therapeutic efficacies.

Depressão em esquizofrenia

Realizou-se uma revisão da literatura acerca da presença de depressão em pacientes esquizofrênicos e, em particular, da depressão pós-esquizofrênica (DPE). A pesquisa foi realizada por meio do Medline, envolvendo os anos de 1966 e 2000, com o objetivo de identificar artigos originais e de revisão. Focalizaram-se os seguintes tópicos: dados históricos, principais estudos, quadro clínico e curso evolutivo, diagnóstico e diagnóstico diferencial, etiopatogenia e prognóstico. Conclui-se que a depressão pós-esquizofrênica tem plena autonomia sindrômica, deve ser considerada uma manifestação clínica das formas delirantes da esquizofrenia e integra o curso evolutivo de um transtorno esquizofrênico.

Dopamine-mediated modulation of odour-evoked amygdala potentials during pavlovian conditioning

Pavlovian conditioning results when an innocuous stimulus, such as an odour, is paired with a behaviourally relevant stimulus, such as a foot-shock, so that eventually the former stimulus alone will elicit the behavioural response of the latter. The lateral nucleus of the amygdala (LAT) is necessary for the emotional memory formation in this paradigm. Enhanced neuronal firing in LAT to conditioned stimuli emerge in parallel with the behavioural changes and are dependent on local dopamine. To study the changes in neuronal excitability and synaptic drive that contribute to the pavlovian conditioning process, here we used in vivo intracellular recordings to examine LAT neurons during pavlovian conditioning in rats. We found that repeated pairings of an odour with a foot-shock resulted in enhanced post-synaptic potential (PSP) responses to the odour and increased neuronal excitability. However, a non-paired odour displayed PSP decrement. The dopamine antagonist haloperidol blocked the PSP enhancement and associated increased neuronal excitability, without reversing previous conditioning. These results demonstrate that conditioning and habituation processes produce opposite effects on LAT neurons and that dopamine is important in these events, consistent with its role in emotional memory formation.

Nonverbal social perception and symptomatology in schizophrenia

This study examined the relationship between nonverbal social perception and symptomatology in schizophrenia. Schizophrenic patients (n=28) and normal controls (n=28) were given the profile of nonverbal sensitivity test (PONS). Patients' symptoms were rated with the brief psychiatric rating scale (BPRS). Schizophrenic subjects performed significantly more poorly than normal subjects in their ability to decode nonverbal cues. In addition, normal subjects improved their accuracy significantly more than patients when provided with additional cues per scene to decode. The patients' total PONS score was not significantly correlated with the BPRS summary scores for positive or negative symptoms, but was significantly correlated with the individual positive symptom of conceptual disorganization. Subjects classified as having paranoid schizophrenia (n=11) on the basis of chart diagnoses performed significantly better on the PONS than did undifferentiated schizophrenic subjects (n=13). The discussion reviews how these results contribute to our understanding of social deficits in schizophrenia.