Early self-experienced neuropsychological deficits and subsequent schizophrenic diseases: an 8-year average follow-up prospective study

Psychosis Risk: Time to Look Empirically at a First-step Economical-pragmatic Way to Examine Anomalous Self-experience. Exploring the SQuEASE-11

BACKGROUND

Since the late 1990s, there has been a worldwide surge of scientific interest in the pre-psychotic phase, resulting in the introduction of several clinical tools for early detection. The predictive accuracy of these tools has been limited, motivating the need for methodological and perspectival improvements. The EASE manual supports systematic assessment of anomalous self-experience, and proposes an overall model of understanding how most psychotic experiences may be initially generated on the basis of a unifying, fundamental, pre-reflective distortion of subjectivity.

STUDY DESIGN

The EASE is time-consuming, so in order to spread the use of this essential perspective of psychosis risk we selected prototypical and frequent phenomena from the EASE, combining them into SQuEASE-11. To investigate this instrument for clinical relevance, basic psychometric properties, factor structure, and relationships with gold standard instruments and the full EASE, it was administered as an interview in the STEP intervention trial (Melbourne, Australia), with 328 clinical high-risk for psychosis (CHR-P) patients.

STUDY RESULTS

The SQuEASE-11 had moderate internal consistency and revealed two correlated factors. Significant relationships were observed between the SQuEASE-11 and the widely used and validated instruments CAARMS, BPRS, SANS, MADRS, DACOBS, and SOFAS. The correlation with the full EASE was very strong.

CONCLUSIONS

These 11 items do not necessarily relate specifically to ipseity disturbance, but the SQuEASE-11 seems to be a clinically relevant and brief supplementary first-line interview in CHR-P subjects. It may give a qualified indication of the need for a complete EASE interview, and it may also, importantly, inform treatment planning.

Basic symptoms influence real-life functioning and symptoms in individuals at high risk for psychosis

OBJECTIVE

To investigate potential clinical differences in high-risk profiles presenting with and without basic symptoms, and additionally investigate the association between basic symptoms and clinical symptoms, functioning, and cognition.

METHODS

High-risk individuals (n = 133) were stratified into individuals fulfilling ultra-high-risk (UHR) criteria (n = 59) and individuals fulfilling UHR+ basic symptoms criteria (BS) (n = 74). Group differences were assessed on clinical symptoms, real-life functioning, and cognition. Regression analyses were conducted to elucidate on the relationship between BS and clinical symptoms, functioning, neurocognition, and social cognition.

RESULTS

The group fulfilling both UHR+ BS criteria had significantly more symptoms and lower real-life functioning and quality of life but not more cognitive deficits. BS influenced on attenuated psychotic, depressive, and general symptoms, but only modestly on negative symptoms. No relationship between BS and neuro- and social cognition was established except for an association with emotion recognition processing speed. BS influenced real-life functioning, and this finding was sustained when controlling for the effect of negative symptoms.

CONCLUSIONS

Our findings indicate that BS contribute highly to the distress and symptom load of clinical high-risk individuals. Longitudinal findings are needed to establish the predictive validity of BS on high-risk individuals' clinical and functional prognosis.

Duration of the psychosis prodrome

The recognition of a prodromal period preceding the onset of frank psychosis dates back to its first descriptions. Despite insights gained from a prospective approach to the study of the Clinical High Risk syndrome for psychosis (CHR-P), a prospectively-based understanding of the duration of the psychosis prodrome and the factors that may influence is not well-established. Here we analyze data from the second North American Prodrome Longitudinal Study (NAPLS-2) to characterize prodrome duration in those who converted to psychosis. Of the 764 participants identified as being at CHR-P, 94 converted to psychosis and 92 of these had recorded estimates of prodrome onset. Estimates of prodrome duration were derived from CHR-P syndrome onset and conversion dates from the Structured Interview for Psychosis-risk Syndromes. Results identified a mean prodrome duration of 21.6 months. Neither CHR-P sub-syndrome nor medication exposure was found to significantly influence prodrome duration in this sample. These results provide the most precise estimate of prodrome duration to date, although results are limited to prodromes identified by ascertainment as being at CHR-P. Our findings also suggest a rule of thirds with regard to prodrome duration in those followed for two years: one third of CHR-P patients who convert will do so by 1 year after CHR-P syndrome onset, another third 1-2 years after onset, and the final third more than 2 years after onset.

Self-disorders in Early Stages of the Schizophrenia Spectrum

The pathogenic nucleus of schizophrenia has varied according to the different eras and influences of distinguished clinical researchers. Self-disorders have also been recognised to be at the heart of this disorder, although they have seldom been studied due to their subjective nature. Recently, due to the growing interest in the study of the early stages of schizophrenia, the study of self-disorders has been resumed. The self-disorders in schizophrenia model, developed by Sass and Parnas, proposes that in this disorder the person suffers loss of the first-person perspective and experiences hyperreflexibility, diminished self-affection and disturbance of the field of awareness. Therefore, the person experiences feelings of strangeness about him/herself, difficulty in understanding the common sense of things and difficulty interacting with his/her environment. Based on this model, self-disorder evaluation instruments have been developed and empirical studies have been conducted to evaluate people at risk of developing a schizophrenia spectrum disorder. These studies show that self-disorders are found in prepsychotic stages and that their manifestation may predict the transition to schizophrenia spectrum disorders. These results have important clinical implications as they enable people in the early stages of the disorder to be identified and create the opportunity to apply early therapeutic interventions.

Early Intervention and a Direction of Novel Therapeutics for the Improvement of Functional Outcomes in Schizophrenia: A Selective Review

BACKGROUND

A recent review reported that the median proportion of patients recovering from schizophrenia was 13.5% and that this did not change over time. Various factors including the duration of untreated psychosis, cognitive impairment, negative symptoms, and morphological changes in the brain influence the functional outcome of schizophrenia. The authors herein reviewed morphological changes in the brain of schizophrenia patients, effects of early intervention, and a direction of developing novel therapeutics to achieve significant improvement of the functional outcome.

METHODS

A selective review of the literature including studies from our department was performed.

RESULTS

Longitudinal structural neuroimaging studies on schizophrenia revealed that volume reductions in the peri-Sylvian regions (e.g., superior temporal gyrus and insula), which are related to positive psychotic symptoms, progress around the onset (critical stage) of schizophrenia, but become stable in the chronic stage. On the other hand, morphological changes in the fronto-thalamic regions and lateral ventricle, which are related to negative symptoms, neurocognitive dysfunction, and the functional outcome, progress during both the critical and chronic stages. These changes in the peri-Sylvian and fronto-thalamic regions may provide a pathophysiological basis for Crow's two-syndrome classification. Accumulated evidence from early intervention trials suggests that the transition risk from an at-risk mental state (ARMS) to psychosis is approximately 30%. Differences in the cognitive performance, event-related potentials (e.g., mismatch negativity), and brain morphology have been reported between ARMS subjects who later developed psychosis and those who did not. Whether early intervention for ARMS significantly improves the long-term recovery rate of schizophrenia patients remains unknown. With respect to the development of novel therapeutics, animal models of schizophrenia based on the N-methyl-d-aspartate receptor hypofunction hypothesis successfully mimicked behavioral changes associated with cognitive impairments characteristic of the disease. Furthermore, these animal models elicited histological changes in the brain similar to those observed in schizophrenia patients, i.e., decreased numbers of parvalbumin-positive interneurons and dendritic spines of pyramidal neurons in the frontal cortex. Some antioxidant compounds were found to ameliorate these behavioral and histological abnormalities.

CONCLUSION

Early intervention coupled with novel therapeutics may offer a promising approach for substantial improvement of the functional outcome of schizophrenia patients.

`Schizophrenic Person' or `Person with Schizophrenia'?

Most contemporary experts and mental health advocates would reject the term `schizophrenic', whether used as noun or adjective. The terminology they prefer—`person with schizophrenia'—seems safely to nominalize the ailment and set it apart from the afflicted person, treating the disease entity as a foreign body. The present essay does not advocate rejecting the current terminology. It offers a critical perspective on the contemporary consensus by considering three aspects of schizophrenia that current terminology downplays or denies: (1) how schizophrenia may not merely hijack but actually transform the self; (2) how schizophrenic psychosis may grow out of a particular personality orientation, thus representing the culmination of a personal trajectory or mode of being; (3) how schizophrenic modes of being can sometimes involve, often in paradoxical ways, certain forms of intentionality, self-awareness, commitment or even quasi-volitional choice. Several disadvantages of the `person with schizophrenia' formula are considered: (1) conceptual oversimplification of the psychological realities of schizophrenia; (2) forms of stigmatizing inherent in the biomedical disease model; (3) closing down a potential `dialogue with madness'.

Discrepancy between self-reported and interviewed psychosis risk symptoms: auditory distortions are the most reliably reported symptom by self-report

AIM

In the recent literature, there has been growing interest in assessment methods for detecting increased risk of developing psychosis. Self-report methods are popular but may lead to different results compared to clinical interviews.

METHODS

The difference in psychosis risk scores was tested between self-reported psychosis risk symptoms (PROD-SR) and self-reported symptoms additionally confirmed by interview (PROD-SR + I). The symptom categories were derived from 12 common psychosis risk symptoms included in the PROD screening instrument. The data were collected by questionnaires and interviews conducted with 395 adolescents (mean age 15.3 years) in an early intervention and detection team, JERI, at Helsinki University Central Hospital, Finland.

RESULTS

The results show a significant difference between the PROD-SR risk symptom sum scores and the PROD-SR + I risk symptom sum scores (N = 395; Z = -15.123; P < 0.001). In an item-by-item analysis, the item 'Disorders in connection with hearing' had the strongest kappa value (0.827) agreement between an interviewed and self-report psychosis risk item. Agreement in most items remained between slight and substantial (kappa values from 0.082 to 0.649).

CONCLUSIONS

The results suggest that there is a significant difference between psychosis risk symptom responses collected by self-report and self-report responses which are additionally confirmed by interview. Auditory disorders are the most reliably reported item with self-report.

The early identification of psychosis: can lessons be learnt from cardiac stress testing?

Psychotic disorders including schizophrenia are amongst the most debilitating psychiatric disorders. There is an urgent need to develop methods to identify individuals at risk with greater precision and as early as possible. At present, a prerequisite for a diagnosis of schizophrenia is the occurrence of a psychotic episode. Therefore, attempting to detect schizophrenia on the basis of psychosis is analogous to diagnosing coronary artery disease (CAD) after the occurrence of a myocardial infarction (MI). The introduction of cardiac stress testing (CST) has revolutionized the detection of CAD and the prevention and management of angina and MI. In this paper, we attempt to apply lessons learnt from CST to the early detection of psychosis by proposing the development of an analogous psychosis stress test. We discuss in detail the various parameters of a proposed psychosis stress test including the choice of a suitable psychological or psychopharmacological "stressor," target population, outcome measures, safety of the approach, and the necessary evolution of test to become clinically informative. The history of evolution of CST may guide the development of a similar approach for the detection and management of psychotic disorders. The initial development of a test to unmask latent risk for schizophrenia will require the selection of a suitable and safe stimulus and the development of outcome measures as a prelude to testing in populations with a range of risk to determine predictive value. The use of CST in CAD offers the intriguing possibility that a similar approach may be applied to the detection and management of schizophrenia.

Social Cognition in Individuals at Ultra-High Risk for Psychosis: A Meta-Analysis

Objective

Treatment in the ultra-high risk stage for a psychotic episode is critical to the course of symptoms. Markers for the development of psychosis have been studied, to optimize the detection of people at risk of psychosis. One possible marker for the transition to psychosis is social cognition. To estimate effect sizes for social cognition based on a quantitative integration of the published evidence, we conducted a meta-analysis of social cognitive performance in people at ultra high risk (UHR).

Methods

A literature search (1970-July 2015) was performed in PubMed, PsychINFO, Medline, Embase, and ISI Web of Science, using the search terms ‘social cognition’, ‘theory of mind’, ‘emotion recognition’, ‘attributional style’, ‘social knowledge’, ‘social perception’, ‘empathy’, ‘at risk mental state’, ‘clinical high risk’, ‘psychosis prodrome’, and ‘ultra high risk’. The pooled effect size (Cohen’s D) and the effect sizes for each domain of social cognition were calculated. A random effects model with 95% confidence intervals was used.

Results

Seventeen studies were included in the analysis. The overall significant effect was of medium magnitude (d = 0.52, 95% Cl = 0.38–0.65). No moderator effects were found for age, gender and sample size. Sub-analyses demonstrated that individuals in the UHR phase show significant moderate deficits in affect recognition and affect discrimination in faces as well as in voices and in verbal Theory of Mind (TOM). Due to an insufficient amount of studies, we did not calculate an effect size for attributional bias and social perception/ knowledge. A majority of studies did not find a correlation between social cognition deficits and transition to psychosis, which may suggest that social cognition in general is not a useful marker for the development of psychosis. However some studies suggest the possible predictive value of verbal TOM and the recognition of specific emotions in faces for the transition into psychosis. More research is needed on these subjects.

Conclusion

The published literature indicates consistent general impairments in social cognition in people in the UHR phase, but only very specific impairments seem to predict transition to psychosis.

[Assessment of mental states at risk of psychotic transition: validation of the French version of the CAARMS]

This article aims to present the validation study of the French version of the Comprehensive Assessment of at risk mental states (CAARMS), an interview that seeks to determine whether young adults criteria for at-risk (AR) mental states, or psychosis. We assessed 40 young subjects, 15 were considered as "prodromal" (Prd) and 10 as experiencing a first episode of psychosis (PEP) by our expert clinician at the center - centre d'évaluation des jeunes adultes et adolescents, University Hospital Centre, Paris - and 15 were healthy controls matched for age and sex. When assessed with the CAARMS, 73 % (n=11) of the prodromal subjects reached the criteria for AR mental state, four subjects did not reach the criteria for AR, nor psychosis (P) and 100 % of the PEP reached the criteria for P. The three groups were significantly different on CAARMS total score (P<0.001) and subscores ; Prd subjects had intermediate scores between PEP (P<0.001) and controls (P<0.001) scores, PEP showing the highest scores. Post-hoc analysis showed that Prd significantly differed from Controls on each subscale (P<0.001) and that Prd differed from PEP on the "positive symptoms" subscale (P<0.001), as well as on "behavioural change" (P=0.021), owing to difference on the item "impaired role function". We used the brief psychiatric rating scale 24 items with anchor (BPRS24-EA) in addition to with the CAARMS, the AR group showed intermediate scores between controls and P subjects. Total scores of both scales were correlated (r=0.408 ; P=0.043) and the BPRS24-EA "positive symptoms" score was correlated with CAARMS' scores on the "Positive symptoms" subscale (r=0.456, P=0.022), "emotional disturbance" (r=0.506, P=0.01), and "behavioural change" (r=0.666 P=0.001). We found no correlation between BPRS negative and depression subscales and any of the CAARMS' subscales. When looking at its reliability, reliability coefficients (Cronbach's alpha) showed excellent reliability for "positive symptoms", "emotional disturbance", "behavioural change" and "general psychopathology" (respectively r=0.82, 0.75, 0.78, 0.84, 0.83) and moderate reliability for "cognitive change", "negative symptoms" and "motor/physical change" (respectively r=0.39, 0.59, 0.43). Overall, analysis of the results of construct validity, concurrent validity and reliability of the CAARMS indicates that the French version is valid and reliable. It is now available to develop and implement early detection programs in French speaking countries.

Health-related quality of life among adolescents: a comparison between subjects at risk for psychosis and other help seekers

AIM

Schizophrenia is a severe illness associated with poor health-related quality of life (HRQoL), and there is some evidence that a risk state for psychosis is associated with decreased HRQoL. The aim of the present study was to investigate group differences in HRQoL in help seekers at risk for psychosis and not at risk for psychosis.

METHODS

The data were collected by a Finnish early detection and intervention team at Helsinki University Central Hospital. A total of 202 help-seeking adolescents (110 girls, 92 boys; 11-22 years of age) were assessed with a PROD screen and HRQoL scale of 16D.

RESULTS

As the main result, subjects at risk for psychosis had a poorer HRQoL index than other help seekers (P < 0.001). An additional analysis of sub-items for the HRQoL at-risk group had poorer mean scores at a statistically significant level after Bonferroni correction for multiple tests in the following sub-items: vitality (P = 0.016), distress (P = 0.016), physical appearance (P < 0.001), school and hobbies (P = 0.016), friends (P = 0.048), mental function (P < 0.001) and depression (P < 0.001). In a logistic regression analysis of sub-items of the HRQoL scale, lower scores in the sub-item of mental function independently explained the at-risk status for psychosis (P = 0.009).

CONCLUSIONS

Adolescents at risk for psychosis have a poorer HRQoL index than other help seekers and they also differ in several sub-items, particularly in the lower scores in mental function. In the future, these findings should be considered in the care of adolescents at risk for psychosis.

Schizophrenia as a self-disorder due to perceptual incoherence

The aim of this review is to describe the potential relationship between multisensory disintegration and self-disorders in schizophrenia spectrum disorders. Sensory processing impairments affecting multisensory integration have been demonstrated in schizophrenia. From a developmental perspective multisensory integration is considered to be crucial for normal self-experience. An impairment of multisensory integration is called 'perceptual incoherence'. We theorize that perceptual incoherence may evoke incoherent self-experiences including depersonalization, ambivalence, diminished sense of agency, and 'loosening of associations' between thoughts, feelings and actions that lie within the framework of 'self-disorders' as described by Sass and Parnas (2003). We postulate that subconscious attempts to restore perceptual coherence may induce hallucinations and delusions. Increased insight into mechanisms underlying 'self-disorders' may enhance our understanding of schizophrenia, improve recognition of early psychosis, and extend the range of therapeutic possibilities.

Adolescents at risk of psychosis have higher level of hopelessness than adolescents not at risk of psychosis

BACKGROUND

Hopelessness has been a widely studied phenomenon in psychotic disorders. However, previous evidence of hopelessness in at-risk state of psychosis is lacking. The primary aim of the present study was to investigate associations between at-risk state of psychosis and the level of hopelessness, the secondary aim being to investigate, at item-level, hopelessness differences in hopelessness profile of adolescents at risk of psychosis.

METHODS

Hopelessness was assessed with the Beck Hopelessness Scale (BHS) and risk of psychosis with the PROD screen by an early detection team at the Helsinki University Central Hospital in a sample of 200 help-seeking adolescents between 11 and 22 years of age. Of them, 66 were classified as belonging to the at-risk of psychosis group and 134 to the not-at-risk of psychosis group.

RESULTS

The at-risk group scored higher in total sum scores of hopelessness than the not-at-risk group (9.15 vs. 6.63, P = 0.002). In an additional analysis of the BHS, the sub-item "I have great faith in the future" (P < 0.001) differed by risk status of psychosis after correction for multiple analysis. In a logistic regression analysis, BHS subfactor III (sum scores of items "I can't imagine what my life would be like in 10 years" and "I don't expect to get what I really want") explained (P = 0.047) the at-risk status of psychosis after age, gender and other BHS subfactors had been adjusted for.

CONCLUSIONS

Adolescents at risk of psychosis have higher hopelessness than other help-seekers. In light of a heightened possibility of suicidal behaviour, psychiatric care should pay attention to these findings.

Validation of the Korean version of the Eppendorf Schizophrenia Inventory as a screening measure to detect adolescents at ultra-high risk for psychosis

AIM

No validated self-report scale is available for use as a screening tool to detect non-help-seeking adolescents at ultra-high risk (UHR) for psychosis in a community setting. The study aims to examine the reliability and validity of the Korean version of the Eppendorf Schizophrenia Inventory (K-ESI) for assessing adolescents at UHR for psychosis in a community setting.

METHODS

In the first study, to confirm the reliability and discriminant validity of the K-ESI, community sample (782 adolescents, 281 young adults, 122 early and middle-aged adults) and outpatients with schizophrenia (109) were recruited. A single cross-sectional survey was performed using the K-ESI for the community sample and the K-ESI and Positive and Negative Syndrome Scale for patients. In the second study, the Korean version of Youth Self Report (K-YSR) was administered initially to 1002 students. Of the 217 students whose scores were equal to or higher than the cut-off point of the K-YSR, 120 who agreed to an in-depth evaluation were interviewed using the Comprehensive Assessment of At-Risk Mental States to confirm the predictive validity of the K-ESI.

RESULTS

The K-ESI showed good internal consistency and excellent test-retest reliability and discriminant validity. However, the factor structure in adolescents was substantially different from that of the original ESI. The best cut-off point for the K-ESI to identify UHR adolescents was 29, with a sensitivity of 77% and a specificity of 70%.

CONCLUSION

The results revealed that the K-ESI can be used as a valid and reliable instrument to identify adolescents at UHR for psychosis in a community setting.

JointMMCC: joint maximum-margin classification and clustering of imaging data

A number of conditions are characterized by pathologies that form continuous or nearly-continuous spectra spanning from the absence of pathology to very pronounced pathological changes (e.g., normal aging, mild cognitive impairment, Alzheimer's). Moreover, diseases are often highly heterogeneous with a number of diagnostic subcategories or subconditions lying within the spectra (e.g., autism spectrum disorder, schizophrenia). Discovering coherent subpopulations of subjects within the spectrum of pathological changes may further our understanding of diseases, and potentially identify subconditions that require alternative or modified treatment options. In this paper, we propose an approach that aims at identifying coherent subpopulations with respect to the underlying MRI in the scenario where the condition is heterogeneous and pathological changes form a continuous spectrum. We describe a joint maximum-margin classification and clustering (JointMMCC) approach that jointly detects the pathologic population via semi-supervised classification, as well as disentangles heterogeneity of the pathological cohort by solving a clustering subproblem. We propose an efficient solution to the nonconvex optimization problem associated with JointMMCC. We apply our proposed approach to an medical resonance imaging study of aging, and identify coherent subpopulations (i.e., clusters) of cognitively less stable adults.

Identification and characterization of prodromal risk syndromes in young adolescents in the community: a population-based clinical interview study

While a great deal of research has been conducted on prodromal risk syndromes in relation to help-seeking individuals who present to the clinic, there is a lack of research on prodromal risk syndromes in the general population. The current study aimed first to establish whether prodromal risk syndromes could be detected in non-help-seeking community-based adolescents and secondly to characterize this group in terms of Axis-1 psychopathology and general functioning. We conducted in-depth clinical interviews with a population sample of 212 school-going adolescents in order to assess for prodromal risk syndromes, Axis-1 psychopathology, and global (social/occupational) functioning. Between 0.9% and 8% of the community sample met criteria for a risk syndrome, depending on varying disability criteria. The risk syndrome group had a higher prevalence of co-occurring nonpsychotic Axis-1 psychiatric disorders (OR = 4.77, 95% CI = 1.81-12.52; P < .01) and poorer global functioning (F = 24.5, df = 1, P < .0001) compared with controls. Individuals in the community who fulfill criteria for prodromal risk syndromes demonstrate strong similarities with clinically presenting risk syndrome patients not just in terms of psychotic symptom criteria but also in terms of co-occurring psychopathology and global functioning.

Differential results between self-report and interview-based ratings of risk symptoms of psychosis

AIM

Assessing potential risk of developing psychosis has gained growing attention in recent literature. The selection of suitable assessment methods is the central question for this research endeavour. Whereas prodromal detection instruments are mostly interview-based instruments, there are short screening instruments for self-report use.

METHODS

Difference in psychosis risk scores was tested between self-report results and interview results, with risk symptoms of psychosis included in PROD screening instrument. Subjects were recruited by an early intervention team in Finland.

RESULTS

There was a significant difference between psychosis risk scores based on self-report versus interview in a sample of adolescents (n=87; P<0.001).

CONCLUSIONS

Results suggest that when using screening instruments, risk scores and risk status may vary by the method the information is collected. Checking self-report results by an additional interview is recommended for both clinical and scientific uses.

Understanding the genesis of psychotic disorder: Issues in the prediction and prophylaxis of those at ultra-high risk

PURPOSE

Recent research is starting to identify individuals at an increased risk of developing a psychotic disorder. This review seeks to identify the 'state of the art' with respect to the clinical identification and treatment of individuals at 'ultra-high risk'.

METHOD

The research and clinical literature are reviewed with respect to a wide range of predictors relevant across development.

RESULTS

The review draws on evidence from childhood and adolescence to suggest that a range of biological, cognitive, personality, and social features are predictive of, but often not specific to, psychosis within the context of the diathesis-stress model. Much evidence supports the view that environmental stressors act in combination with vulnerability factors to increase risk of transition, often during late adolescence and early adulthood.

CONCLUSIONS

Recent clinical research has used both retrospective and prospective means of identifying individuals at ultra-high risk and has made substantial gains in predicting transition. The clinical implications of their identification are discussed in the context of current pharmacological and psychosocial treatment studies. However, significant unresolved clinical and ethical issues remain with both types of study.

Prevalence and intensity of basic symptoms among cannabis users: an observational study

BACKGROUND

It is difficult to establish whether people who are prone to psychosis are drawn to cannabis use or whether cannabis use truly increases the incidence of psychotic experiences.

OBJECTIVES

The aim of our study was to evaluate, in a sample of healthy high school and university students, the presence and level of subjective experiences (SEs) and their relation to cannabis use.

METHODS

A total of 502 voluntary subjects were recruited; an anamnestic interview was administered to obtain socio-demographic information, cannabis use data, and psychiatric familial history. SEs were assessed using the Italian version of the Frankfurt Complaint Questionnaire (FCQ).

RESULTS

One hundred and fourteen subjects declared the use of cannabis: 20.5% smoked more than 1 joint per week, and 71.9% used cannabis for a period of more than 1 year. Cannabis users did not differ from the cannabis-free group in any of the 10 FCQ dimensions. Higher FCQ total scores were found in cannabis users with a familial history of psychiatric disorders respective to those without a psychiatric load (p<.05).

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

In our study, SE intensity was not influenced by the use of cannabis. With regard to familial data, this is the first study to explore the relationship between SE and the presence of psychiatric problems in first-degree relatives. The association between FCQ intensity and psychiatric familial load may confirm the independence of these phenomena from the use of cannabis.

What factors are related to delayed treatment in individuals at high risk for psychosis?

BACKGROUND

Previous studies have shown that the individuals at high risk for psychosis suffer from depression, anxiety, and deficits in social functioning. The present report describes help-seeking behaviours, baseline psychopathology, and duration of attenuated psychotic symptoms (DUAPS) and their associations with other variables.

METHODS

Using the Comprehensive Assessment of At-Risk Mental States (CAARMS), we conducted systematic evaluations of individuals at high risk for psychosis. Help-seeking behaviours, current Axis I diagnoses, DUAPS, and baseline psychopathology were investigated. Demographic and clinical characteristics of short and long DUAPS groups were compared.

RESULTS

Thirty-eight subjects were recruited from nine centres. Participants seldom sought psychiatric services at their first help-seeking contact, and the mean DUAPS was 22.00 +/- 28.59 months. Most participants had current Axis I diagnoses, and depressive disorder NOS was the most common of these. Higher levels of depression, anxiety, obsessive-compulsive symptoms, and functional impairment were also identified. We found no significant differences between short and long DUAPS groups in baseline psychopathology. However, we observed significantly lesser distressing intensity of thought contents and significantly greater social impairment in the long-DUAPS group.

CONCLUSION

These findings suggest that high-risk subjects frequently received delayed treatment despite symptomatic distress and functional impairment. No direct evidence supporting the delayed effect of the DUAPS on baseline psychopathology was found.

Neuroanatomical correlates of different vulnerability states for psychosis and their clinical outcomes

BACKGROUND

Structural brain abnormalities have been described in individuals with an at-risk mental state for psychosis. However, the neuroanatomical underpinnings of the early and late at-risk mental state relative to clinical outcome remain unclear.

AIMS

To investigate grey matter volume abnormalities in participants in a putatively early or late at-risk mental state relative to their prospective clinical outcome.

METHOD

Voxel-based morphometry of magnetic resonance imaging data from 20 people with a putatively early at-risk mental state (ARMS-E group) and 26 people with a late at-risk mental state (ARMS-L group) as well as from 15 participants with at-risk mental states with subsequent disease transition (ARMS-T group) and 18 participants without subsequent disease transition (ARMS-NT group) were compared with 75 healthy volunteers.

RESULTS

Compared with healthy controls, ARMS-L participants had grey matter volume losses in frontotemporolimbic structures. Participants in the ARMS-E group showed bilateral temporolimbic alterations and subtle prefrontal abnormalities. Participants in the ARMS-T group had prefrontal alterations relative to those in the ARMS-NT group and in the healthy controls that overlapped with the findings in the ARMS-L group.

CONCLUSIONS

Brain alterations associated with the early at-risk mental state may relate to an elevated susceptibility to psychosis, whereas alterations underlying the late at-risk mental state may indicate a subsequent transition to psychosis.

Subjective experience of cognitive failures as possible risk factor for negative symptoms of psychosis in the general population

OBJECTIVE

The aim of this study was to examine whether proneness to subjective cognitive failure (cognitive based mistakes) increases the risk for the development of symptoms of psychosis and to what degree any association was familial.

METHODS

At baseline, the Cognitive Failure Questionnaire (CFQ) and the Community Assessment of Psychic Experiences (CAPE) questionnaire were administered in a general population sample of genetically related individuals (n = 755). Individuals scoring high (>75th percentile) or average on the CAPE (between 40th and 60th percentile) (n = 488) were reinterviewed with the CAPE and Structured Interview for Schizotypy-Revised (SIS-R) at follow-up (mean interval = 7.7 months, SD = 4.8 months).

RESULTS

Cross-trait, within-relative analysis showed a significant association between the CFQ and the negative dimension, assessed with both the CAPE and SIS-R, whereas no association was found between the CFQ and the positive dimension. Cross-trait, between-relative analyses showed no association between the CFQ in one relative and any of the dimensions of the subclinical psychosis phenotype in the other relative.

CONCLUSION

Proneness to subjective cognitive failure possibly contributes to the development or persistence of negative symptoms and can be seen as potential risk factor for negative symptoms of psychosis. This overlap is due to individual effects rather than familial liability.

Use of neuroanatomical pattern classification to identify subjects in at-risk mental states of psychosis and predict disease transition

CONTEXT

Identification of individuals at high risk of developing psychosis has relied on prodromal symptomatology. Recently, machine learning algorithms have been successfully used for magnetic resonance imaging-based diagnostic classification of neuropsychiatric patient populations.

OBJECTIVE

To determine whether multivariate neuroanatomical pattern classification facilitates identification of individuals in different at-risk mental states (ARMS) of psychosis and enables the prediction of disease transition at the individual level.

DESIGN

Multivariate neuroanatomical pattern classification was performed on the structural magnetic resonance imaging data of individuals in early or late ARMS vs healthy controls (HCs). The predictive power of the method was then evaluated by categorizing the baseline imaging data of individuals with transition to psychosis vs those without transition vs HCs after 4 years of clinical follow-up. Classification generalizability was estimated by cross-validation and by categorizing an independent cohort of 45 new HCs.

SETTING

Departments of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, Munich, Germany.

PARTICIPANTS

The first classification analysis included 20 early and 25 late at-risk individuals and 25 matched HCs. The second analysis consisted of 15 individuals with transition, 18 without transition, and 17 matched HCs.

MAIN OUTCOME MEASURES

Specificity, sensitivity, and accuracy of classification.

RESULTS

The 3-group, cross-validated classification accuracies of the first analysis were 86% (HCs vs the rest), 91% (early at-risk individuals vs the rest), and 86% (late at-risk individuals vs the rest). The accuracies in the second analysis were 90% (HCs vs the rest), 88% (individuals with transition vs the rest), and 86% (individuals without transition vs the rest). Independent HCs were correctly classified in 96% (first analysis) and 93% (second analysis) of cases.

CONCLUSIONS

Different ARMSs and their clinical outcomes may be reliably identified on an individual basis by assessing patterns of whole-brain neuroanatomical abnormalities. These patterns may serve as valuable biomarkers for the clinician to guide early detection in the prodromal phase of psychosis.

The concept of psychosis: historical and phenomenological aspects

The historical development of the concept of psychosis and its increasing differentiation from the neuroses up to the modern classification systems, Diagnostic and Statistical Manual of Mental Disorders and International Statistical Classification of Diseases, is initially presented. In portraying this development, the struggle surrounding the clinical relevance of concepts on the one hand and their reliability and validity on the other are reflected. Thus far, diagnostic reliability has primarily been improved by focusing on externally observable symptoms in connection with expression and behavior. The identification of disease-specific symptoms, however, is principally achieved through the differential description of subjective experience. How this experience is to be explored and assessed remains for the most part unclear. With reference to its founder Karl Jaspers, the phenomenological method is presented as the decisive instrument for the assessment of experience. It is shown that a return to the legacy of phenomenology and a reformulation of the long-standing question concerning the specific symptoms of the schizophrenic psychosis are currently in progress. The revival of historical knowledge and a focus on direct clinical phenomena continue to provide inspiration for further advancement in modern psychiatry.

The proximal prodrome to first episode mania--a new target for early intervention

OBJECTIVE

Affective psychoses and bipolar disorders have been neglected in the development of early intervention strategies. This paper aims to gather current knowledge on the early phase of bipolar disorders in order to define new targets for early intervention.

METHODS

Literature review based on the main computerized databases (MEDLINE, PUBMED and PSYCHLIT) and hand search of relevant literature.

RESULTS

Based on current knowledge, it is likely that an approach aiming at the identification of impending first-episode mania is the most realistic and manageable strategy to promote earlier treatment. During the period preceding the onset of the first manic episode, patients go through a prodromal phase marked by the presence of mood fluctuation, sleep disturbance, and other symptoms such as irritability, anger, or functional impairment. Additionally, various risk factors and markers of vulnerability to bipolar disorders have been identified.

CONCLUSIONS

In the few months preceding first-episode mania, patients go through a prodrome phase (proximal prodrome) that could become an important target for early intervention. However, considering the low specificity of the symptoms observed during this phase, criteria defining high-risk profiles to first-episode mania should also include certain risk factors or markers of vulnerability. While more research is needed in high-risk groups (e.g., bipolar offspring), retrospective studies conducted in first-episode mania cohorts could provide valuable information about this critical phase of the illness.

Prediction of psychosis: setting the stage

Treating psychotic disorders in their earliest stages has become a key focus for research and clinical care. This paper reviews evidence of the capacity to identify those at increased risk for psychotic disorder and to intervene in the identified, high-risk individuals to ameliorate the course of disorder. Issues involved in preventive oriented clinical care are addressed, such as risk/benefit considerations, ethical and safety issues and the value of stage-specific interventions. Clinical predictors identified in recent research, promising intervention trials and proposed clinical practice guidelines are described. An approach based on active engagement, support and monitoring, yet with a conservative approach to medication use is advocated at present. Potential neurobiological processes have been studied and reinforce the sense that this is a critical phase for active treatment, and may prove helpful in understanding the process of transition across stages of illness. More research is required in prediction, neurobiology and treatment.

Two new scales of formal thought disorder in schizophrenia

Information provided by patients and respective carers may help to understand formal thought disorder (FTD) in schizophrenia. Two scales, one for patients (FTD-patient) and one for carers (FTD-carer), were constructed to assess pragmatics, cognitive, paralinguistic, and non-verbal aspects of communication. In the first scale the patients themselves assess their verbal communication; in the second scale the carer assesses the speech of the respective patient. Both scales exhibited internal reliability and evidence of good test-retest reliability. Higher total scores on both scales (FTD-patient and FTD-carer) were significantly associated with positive FTD, but not with negative FTD. Principal component analysis of the scales yielded a multidimensional structure. It is suggested that FTD in schizophrenia may be associated with a range of deficits (e.g. pragmatics, lexical activation, working memory, sustained attention). These scales, in conjunction with the clinician's assessment, can provide a more comprehensive picture of FTD in schizophrenia, revealing its dimensions and making it possible to establish associations between symptoms of FTD and neuropsychological, neurophysiologic, and neuroimaging data. In addition, they provide service users' and carers' perspectives for the assessment of communication in schizophrenia.

[Early recognition and intervention for schizophrenia]

Studies dealing with the prodromal stage of schizophrenia point to the possibility of early detection and early intervention. Major socioeconomic and social consequences are associated with this disorder. The duration of untreated psychosis seems to play an important role in the course of the disease; i.e. a prolonged duration until adequate treatment is obtained correlates to poorer prognosis. Social, cognitive, affective, and structural brain variations appear in the early prodromal stage. Recent early intervention studies show the possibility of reducing transition rates by preventive treatment of patients at a higher risk of psychosis and already manifesting impaired function. In this review, prodromal signs and possibilities for early detection and intervention in schizophrenia are presented.

Functional imaging as a predictor of schizophrenia

BACKGROUND

Prospective studies of young individuals at high risk of schizophrenia allow the investigation of whether neural abnormalities predate development of illness and, if present, have the potential to identify those who may become ill.

METHODS

We studied young individuals with at least two relatives with the disorder. At baseline functional magnetic resonance imaging (fMRI) scan, none met criteria for any psychiatric disorder, but four subjects subsequently developed schizophrenia. We report the baseline functional imaging findings in these subjects performing a sentence completion task compared with normal control subjects (n = 21) and those at high risk with (n = 21) and without (n = 41) psychotic symptoms who have not developed the disorder.

RESULTS

High-risk subjects who became ill demonstrated increased activation of the parietal lobe, decreased activation of the anterior cingulate, and smaller increases in activation with increasing task difficulty in the right lingual gyrus and bilateral temporal regions. The hypothesized predictive power of parietal activation was supported only in combination with lingual gyrus activity, which gave a positive predictive value in this sample of .80.

CONCLUSIONS

Although these findings should be considered cautiously, as only four subjects who had an fMRI scan subsequently became ill, they suggest functional abnormalities are present in high-risk subjects who later became ill, which distinguish them not only from normal control subjects but also those at high risk who had not developed the disorder. These differences are detectable with fMRI and may have clinical utility.

Transition to psychosis: 6-month follow-up of a Chinese high-risk group in Hong Kong

OBJECTIVES

The identification of individuals at high risk of becoming psychotic within the near future creates opportunities for early intervention before the onset of psychosis. This study sets out to identify a group of symptomatic young people in a Chinese population with the high likelihood of transition to psychosis within a follow-up period of 6 months, and to determine the rate of transition to psychosis in this group.

METHOD

Symptomatic individuals with a family history of psychotic disorder, sub-threshold psychotic symptoms or brief transient psychotic symptoms were identified using the operationalized criteria of an 'At Risk Mental State'. The individuals were prospectively assessed monthly on a measure of psychopathology for 6 months.

RESULTS

Eighteen out of 62 individuals (29%) made the transition to frank psychosis within a 6 month follow-up period, with the majority occurring within 3 months. In addition, significant differences were found in the intake Positive and Negative Syndrome Scale, Comprehensive Assessment of 'At Risk Mental State' and Global Assessment of Functioning scores between the group that ultimately became psychotic and the group that did not.

CONCLUSION

The period of the highest risk of transition to psychosis was within the 3 months after the study began. Thus, distressed youths in our outpatient clinic, who meet the high-risk criteria should be monitored most closely in the initial 3 months, particularly those individuals with high levels of psychopathology and functional decline.

Prospective investigations of the prodromal state of schizophrenia: review of studies

OBJECTIVE

The paper presents a comprehensive overview of prospective studies monitoring or intervening in the pre-onset phase of first episode psychosis.

METHOD

A systematic literature search was conducted and supplemented by a manual search. All relevant studies were ordered and intensively reviewed according to specified criteria. Methodological and conceptual issues are discussed.

RESULTS

Reports of 23 prospective studies were found, some describing subsamples of larger samples. Major methodological and conceptual divergences exist.

CONCLUSION

Applied criteria detect individuals with a significantly increased risk of psychosis within the schizophrenia spectrum, but these criteria are only validated on clinical populations. The significance of differences in sample-characteristics is unclear. Most study samples are small. Results are preliminary and in need of further research before they constitute a realistic knowledge base. Methodological and conceptual issues should not be underestimated.

Subjective experiences and the psychopathological dimensions in schizophrenia

The aim of this article was to explore the relationships between subjective experience (SE) and objective symptoms in schizophrenia. Exploratory principal component analysis was used to determine the latent organization of the variables. A group of 310 chronic patients with schizophrenia who met ICD-10 criteria for F20 schizophrenic disorder were included in the study. SE and objective symptoms were rated using, respectively, the 24-item version of the Frankfurt Complaint Questionnaire (FCQ-24) and the Positive and Negative Syndrome Scale (PANSS). An exploratory principal component analysis was performed on the correlation matrix comprising items from both the FCQ-24 and the PANSS. Using several guidelines to select the number of factors, the exploratory principal component analysis yielded a six-factor solution with no overlap of the significant factor loadings for the items from each scale. These six factors represent, respectively, the subjective, negative, positive, disorganization, hostility and anxious-depressive dimensions of the schizophrenic phenomenology. The findings support the view that SE is a construct that is separate and distinct from the objective symptomatology in schizophrenia.

Mapping the onset of psychosis: the Comprehensive Assessment of At-Risk Mental States

OBJECTIVE

Recognizing the prodrome of a first psychotic episode prospectively creates the opportunity of intervention, which could delay, ameliorate or even prevent onset. Valid criteria and a reliable methodology for identifying possible prodromes are needed. This paper describes an instrument, the Comprehensive Assessment of At-Risk Mental States (CAARMS), which has been designed for such a purpose. It has two functions: (i) to assess psychopathology thought to indicate imminent development of a first-episode psychotic disorder; and (ii) to determine if an individual meets criteria for being at ultra high risk (UHR) for onset of first psychotic disorder. This paper describes the pilot evaluation of the CAARMS.

METHOD

Several methodologies were used to test the CAARMS. First, CAARMS scores in a group of UHR young people and the association between CAARMS scores and the risk of transition to psychotic disorder, were analysed. Second, CAARMS scores in a UHR group were compared to a control group. To assess concurrent validity, CAARMS-defined UHR criteria were compared to the existing criteria for identifying the UHR cohort. To assess predictive validity, the CAARMS-defined UHR criteria were applied to a sample of 150 non-psychotic help-seekers and rates of onset of psychotic disorder at 6-month follow-up determined for the CAARMS-positive (i.e. met UHR criteria) group and the CAARMS-negative (i.e. did not meet UHR criteria) group. The inter-rater reliability of the CAARMS was assessed by using pairs of raters.

RESULTS

High CAARMS score in the UHR group was significantly associated with onset of psychotic disorder. The control group had significantly lower CAARMS scores than the UHR group. The UHR criteria assessed by the CAARMS identified a similar group to the criteria measured by existing methodology. In the sample of non-psychotic help-seekers those who were CAARMS-positive were at significantly increased risk of onset of psychotic disorder compared to those who were CAARMS-negative (relative risk of 12.44 (95% CI = 1.5-103.41, p = 0.0025)). The CAARMS had good to excellent reliability.

CONCLUSIONS

In these preliminary investigations, the CAARMS displayed good to excellent concurrent, discriminant and predictive validity and excellent inter-rater reliability. The CAARMS instrument provides a useful platform for monitoring subthreshold psychotic symptoms for worsening into full-threshold psychotic disorder.

Eppendorfer Schizophrenie-Inventar (ESI) vs. Frankfurter Beschwerde-Fragebogen (FBF)

This study is the first to directly compare two clinical questionnaires which are both aimed at self-experienced cognitive dysfunctions of schizophrenia: Eppendorf Schizophrenia Inventory (ESI) and Frankfurt Complaint Questionnaire (FCQ). Evaluated were (a) diagnostic validity, (b) psychometric properties, (c) scale intercorrelations, and (d) factor analytic stability. Ad (a): schizophrenic subjects (n=36) show highly significant increases in the ESI scales and sum score when compared to other clinical groups (patients with depression, alcohol dependence, or obsessive-compulsive disorder, n>30, respectively); on the other hand, the FCQ yields no systematic group differences. Ad (b): mean of reliability coefficients (Cronbach alpha) of the ESI scales is r(tt)=0.86, mean of reliability coefficients of the FCQ scales is significantly lower. Ad (c): the mean intercorrelation between ESI and FCQ scales amounts to r(xy)=0.56 (minimum 0.29, maximum 0.73), corresponding to an average shared variance of about 31%. Ad (d): factor analysis yielded an ESI factor and a FBF factor; one-way ANOVA with the factor scores confirms the diagnostic validity of the ESI.

CONCLUSIONS

ESI and FCQ measure essentially different aspects of schizophrenic psychopathology. Regarding reliability and diagnostic validity, the ESI is superior to the FCQ.

Abnormal subjective experiences of schizophrenia: evaluation of the Eppendorf Schizophrenia Inventory

The Eppendorf Schizophrenia Inventory (ESI) is a new clinical questionnaire aimed at self-experienced cognitive disturbances that are considered to be diagnostically specific for schizophrenia. Two ESI validation studies are presented in this report. The aim of study I was to search for objective correlates of the ESI in 100 schizophrenic inpatients. In study II, the diagnostic validity of the ESI was examined by group comparisons (inpatients with first episode or chronic schizophrenia, alcoholism, depression, or obsessive-compulsive disorder, and healthy adults). Study I yielded numerous plausible correlations between ESI subscales and other clinical scales, neuropsychological tests, psychopathological interview data, and neurological symptoms. Study II supported the diagnostic validity of the ESI. A confirmatory factor analysis conducted with the combined schizophrenic sample from both studies corroborated the assumed factor structure. These results confirm the reliability and validity of the ESI.

The psychosis prodrome in adolescent patients viewed through the lens of DSM-IV

OBJECTIVE

Recently developed research criteria have made it possible to identify adolescents at imminent risk for psychosis. However, the array of symptomatology in these patients is broad and has not yet been systematically characterized using established diagnostic and assessment tools.

METHOD

The authors characterized 24 adolescent research participants at the UCLA Center for the Assessment and Prevention of Prodromal States (CAPPS) using structured interviews for the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, (DSM-IV), the Child Behavior Checklist (CBCL), and information regarding psychiatric treatment histories. Two composite cases are also presented.

RESULTS

The most common DSM-IV diagnosis at study entry was major depression, followed by anxiety disorder not otherwise specified (NOS), and social phobia. Most participants met criteria for at least one subthreshold condition, including obsessive-compulsive disorder (OCD), psychosis, mania or hypomania, and generalized anxiety. CBCL data revealed high rates of affective disturbance and broad-ranging symptomatology, as did participants' diagnostic and treatment histories.

CONCLUSIONS

Consistent with retrospective studies of patients with first-episode psychosis, findings revealed frequent mood and anxiety disturbance during the prodromal phase of illness. The DSM-IV does not offer a clear framework for describing the widespread subthreshold symptomatology that characterizes putatively prodromal patients. The authors consider whether the psychosis prodrome merits designation as a recognized clinical entity.

Experiential anomalies and self-centrality in schizophrenia

BACKGROUND

Contemporary psychopathological research has shown that some qualitative anomalies of the first-person experiential givenness qualify the subjective experience of schizophrenia. Such essential clinical features of schizophrenia have recently been condensed into 7 phenomenologically coherent clusters derived from the Bonn Scale for the Assessment of Basic Symptoms (BSABS). The experimental intent of this study was to test whether subapophanic self-centrality (i.e. a protopathic nondelusional form of intersubjective spatial disattunement) empowers the discriminant capacity of such a set of subjective experiential disturbances among different diagnostic groups.

METHOD

Three comparably sized samples of outpatients with schizophrenia, obsessive-compulsive or mood disorders were examined with the BSABS. Logistic regression analysis was performed with diagnosis as the outcome variable.

RESULTS

Elevated scores in self-perceived cognitive disorders and abnormal self-centrality were associated with DSM-IV diagnosis of schizophrenia. Self-centrality increased the discriminant capacity of the 7 designed a priori dimensions.

CONCLUSIONS

These findings confirm the previously reported aggregation of some subtle qualitative alterations of subjective experience in schizophrenia, and suggest that a careful consideration of autocentric disturbances of intersubjectivity might enrich current heuristics on schizophrenic experiential vulnerability.

Autochthonous experience, heightened awareness, and perception distortion in patients with schizophrenia: a symptomatological study

Early symptoms of schizophrenia' (ESS) proposed by Nakayasu, are present during schizophrenic prodromal periods. Some of these symptoms can continue after the florid manifestation of the disease and the patients often experience them with ego-alien feelings. Autochthonous experience, heightened awareness, and perception distortion (AHP) were selected from the list of ESS. The aim of this study was to confirm both prevalence and specificity of AHP in patients with schizophrenia as well as the relevance of the presence of AHP to symptomatology of schizophrenia. A structured interview was conducted to identify the presence of AHP in three groups of subjects; a schizophrenia group (Sc) with 37 patients, an affective disorder group (AD) with 27 patients, and a control group (NC) with 39 people. The prevalence of AHP was compared among the groups. Within the Sc, the relevance of AHP to Brief Psychiatric Rating Scale (BPRS) was assessed. AHP were present significantly more frequently in the Sc. The total scores for BPRS in the schizophrenic patients with AHP were significantly higher than in the patients without AHP. There was close correlation between AHP and BPRS items, with the degree of relevance depending on the form or perceptual domain. In conclusion, AHP were characteristic of patients with frank schizophrenia. To judge whether AHP were adequately specific to frank schizophrenia, further research of larger subjects is needed. Understanding the characteristics of AHP in patients with frank schizophrenia is important in the symptomatological evaluation of schizophrenia.

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

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

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

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

No blind schizophrenics: Are NMDA-receptor dynamics involved?

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

Setting domain boundaries for convergence of biological and psychological perspectives on cognitive coordination in schizophrenia

The claim that the disorganized subtype of schizophrenia results from glutamate hypofunction is enhanced by consideration of current subtypology of schizophrenia, symptom definition, interdependence of neurotransmitters, and the nature of the data needed to support the hypothesis. Careful specification clarifies the clinical reality of disorganization as a feature of schizophrenia and increases the utility of the subtype.

Schizophrenia: Putting context in context

Although context-processing deficits may be core features of schizophrenia, context remains a poorly defined concept. To test Phillips & Silverstein's model, we need to operationalize context more precisely. We offer several useful ways of framing context and discuss enhancing or facilitating schizophrenic patients' performance under different contextual situations. Furthermore, creativity may be a byproduct of cognitive uncoordination.

Phenomenology, context, and self-experience in schizophrenia

Impairments in cognitive coordination in schizophrenia are supported by phenomenological data that suggest deficits in the processing of visual context. Although the target article is sympathetic to such a phenomenological perspective, we argue that the relevance of phenomenological data for a wider understanding of consciousness in schizophrenia is not sufficiently addressed by the authors.

Guarding against over-inclusive notions of “context”: Psycholinguistic and electrophysiological studies of specific context functions in schizophrenia

Phillips & Silverstein offer an exciting synthesis of ongoing efforts to link the clinical and cognitive manifestations of schizophrenia with cellular accounts of its pathophysiology. We applaud their efforts but wonder whether the highly inclusive notion of “context” adequately captures some important details regarding schizophrenia and NMDA/glutamate function that are suggested by work on language processing and cognitive electrophysiology.

Mechanisms of disrupted language comprehension in schizophrenia

Mechanisms that contribute to perceptual processing dysfunction in schizophrenia were examined by Phillips & Silverstein, and formulated as involving disruptions in both local and higher-level coordination of signals. We agree that dysfunction in the coordination of cognitive functions (disconnection) is also indicated for many of the linguistic processing deficits documented for schizophrenia. We suggest, however, that it may be necessary to add a timing mechanism to the theoretical account.

Theory of mind in schizophrenia: Damaged module or deficit in cognitive coordination?

Schizophrenics exhibit a deficit in theory of mind (ToM), but an intact theory of biology (ToB). One explanation is that ToM relies on an independent module that is selectively damaged. Phillips & Silverstein's analyses suggest an alternative: ToM requires the type of coordination that is impaired in schizophrenia, whereas ToB is spared because this type of coordination is not involved.