Neurocognitive function and insight in schizophrenia: support for an association with impairments in executive function but not with impairments in global function

Neurobehavioral Profiles of Six Genetically-based Rat Models of Schizophrenia- related Symptoms

Schizophrenia is a chronic and severe mental disorder with high heterogeneity in its symptoms clusters. The effectiveness of drug treatments for the disorder is far from satisfactory. It is widely accepted that research with valid animal models is essential if we aim at understanding its genetic/ neurobiological mechanisms and finding more effective treatments. The present article presents an overview of six genetically-based (selectively-bred) rat models/strains, which exhibit neurobehavioral schizophrenia-relevant features, i.e., the Apomorphine-susceptible (APO-SUS) rats, the Low-prepulse inhibition rats, the Brattleboro (BRAT) rats, the Spontaneously Hypertensive rats (SHR), the Wisket rats and the Roman High-Avoidance (RHA) rats. Strikingly, all the strains display impairments in prepulse inhibition of the startle response (PPI), which remarkably, in most cases are associated with novelty-induced hyperlocomotion, deficits of social behavior, impairment of latent inhibition and cognitive flexibility, or signs of impaired prefrontal cortex (PFC) function. However, only three of the strains share PPI deficits and dopaminergic (DAergic) psychostimulant-induced hyperlocomotion (together with prefrontal cortex dysfunction in two models, the APO-SUS and RHA), which points out that alterations of the mesolimbic DAergic circuit are a schizophrenia-linked trait that not all models reproduce, but it characterizes some strains that can be valid models of schizophrenia-relevant features and drug-addiction vulnerability (and thus, dual diagnosis). We conclude by putting the research based on these genetically-selected rat models in the context of the Research Domain Criteria (RDoC) framework, suggesting that RDoC-oriented research programs using selectively-bred strains might help to accelerate progress in the various aspects of the schizophrenia-related research agenda.

Insight in substance use disorder: A systematic review of the literature

Insight refers to a person's understanding of themselves and the world around them. Recent literature has explored people's insight into their substance use disorder (SUD) and how this is linked to treatment adherence, abstinence rates, and comorbid mental health symptoms. The aim of this systematic review was to synthesise and critically examine the existing literature on insight in SUD. Five academic databases (Medline, PsychINFO, SCOPUS, CINAHL, Web of Science) were searched for key terms related to insight and substance use. Included studies were on humans aged 18 years or over with SUD that examined the relationship between substance use and insight using a quantifiable measure of insight. Of 10,067 identified papers, 20 met the inclusion criteria, employing 13 different measures of insight. The most commonly used measure was the Hanil Alcohol Insight Scale (HAIS) which was the only measure designed for a substance use population and was specific to alcohol use. Based on a pooled sample from five studies (n = 585), 57% of participants had poor insight, 36% had fair insight, and 7% had good insight on the HAIS. Better insight was generally related to negative consequences from substance use, better treatment adherence and maintaining abstinence. Insight appears to be an important factor to consider within SUD. Exploring the most appropriate way to measure insight and assess its role in SUD has implications for intervention design, and engaging and maintaining people with SUD in treatment.

Correlating cognitive functions to symptom domains and insight in Egyptian patients with schizophrenia

INTRODUCTION

Cognitive impairment is one of the fundamental features among patients with schizophrenia. The relationship between schizophrenia symptoms, insight and cognitive domains remains controversial. We aimed to study these relations in a sample of Egyptian patients with schizophrenia.

METHODS

A total of 109 patients with schizophrenia were assessed using Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders (4th ed.)) Axis I diagnosis (SCID-I), Positive and Negative Syndrome Scale (PANSS) and Scale to Assess Unawareness of Medical Disorder (SUMD). Cognitive functions were assessed using the Wechsler Adult Intelligence Scale (WAIS), the Wisconsin Card Sorting Test (WCST) and the Wechsler Memory Scale (WMS). The cognitive functions would be distributed to cover six cognitive domains: attention/vigilance speed of processing, verbal learning, visual learning, working memory and reasoning/problem solving.

RESULTS

There was a significant correlation between all cognitive domains (except attention) and PANSS subscales. PANSS negative and general psychopathology subscales were significantly correlated with five cognitive domains: speed of processing, verbal learning, visual learning, working memory and reasoning/problem solving. PANSS negative subscale was significantly correlated with verbal learning (verbal paired association 1) and visual learning (visual paired association 1). There was a significant correlation between all cognitive domains and SUMD, except verbal and visual learning domains assessed by verbal and visual paired association 1 subtests, as well as attention assessed by failure to maintain set subtest. Only visual learning (trials administered), working memory (percentage error), and processing speed (perseverative responses, and trials to complete first category) were significantly negatively correlated to SUMD.

CONCLUSION

Cognitive impairment in patients with schizophrenia is most likely to underlie negative symptoms, general psychopathology symptoms and poor insight, suggesting that treatment strategies minimizing these symptoms would improve cognitive impairment.

The relation between neurocognitive dysfunction and impaired insight in patients with schizophrenia

Objectives

The present study aimed to (i) evaluate the association between insight and measures of executive functions and working memory in a sample of 132 patients with schizophrenia and (ii) to explore to what proportion neurocognitive dysfunction contributed to the variance in insight after controlling for symptomatology.

Methods

Subjects were evaluated with a standardized neurocognitive test battery and a semi-structured interview, the Psychosis Evaluation tool for Common use by Caregivers (PECC). PECC, apart from evaluating symptoms and side-effects, measures insight on a 4-point scale by two of its dimensions: awareness of having a mental illness (AMI) and awareness of having symptoms attributed to a mental illness (ASAMI). Executive functioning was measured by the Wisconsin Card Sort Test (WCST) and the Trail Making B (TMB). Working memory was measured by the Letter Number Sequencing (LNS) test from the Wechsler Adult Intelligence Scale (WAIS).

Results

Only one significant association was found after correction for multiple testing, between WCST categories completed and AMI (r = −0.29, p = 0.0006). WCST categories completed explained only 7.9% of the variance in AMI, while symptomatology explained 20% of variance in AMI and 16.5% of variance in ASAMI.

Conclusions

The current results show a significant but subtle association with the WCST, which is in agreement with earlier literature. No other associations between cognitive functioning and insight were found. In general, these findings seem to suggest that factors other than cognition have a greater impact on insight in patients with schizophrenia.

Motivational deficits in schizophrenia relate to abnormalities in cortical learning rate signals

Individuals from across the psychosis spectrum display impairments in reinforcement learning. In some individuals, these deficits may result from aberrations in reward prediction error (RPE) signaling, conveyed by dopaminergic projections to the ventral striatum (VS). However, there is mounting evidence that VS RPE signals are relatively intact in medicated people with schizophrenia (PSZ). We hypothesized that, in PSZ, reinforcement learning deficits often are not related to RPE signaling per se but rather their impact on learning and behavior (i.e., learning rate modulation), due to dysfunction in anterior cingulate and dorsomedial prefrontal cortex (dmPFC). Twenty-six PSZ and 23 healthy volunteers completed a probabilistic reinforcement learning paradigm with occasional, sudden, shifts in contingencies. Using computational modeling, we found evidence of an impairment in trial-wise learning rate modulation (α) in PSZ before and after a reinforcement contingency shift, expressed most in PSZ with more severe motivational deficits. In a subsample of 22 PSZ and 22 healthy volunteers, we found little evidence for between-group differences in VS RPE and dmPFC learning rate signals, as measured with fMRI. However, a follow-up psychophysiological interaction analysis revealed decreased dmPFC-VS connectivity concurrent with learning rate modulation, most prominently in individuals with the most severe motivational deficits. These findings point to an impairment in learning rate modulation in PSZ, leading to a reduced ability to adjust task behavior in response to unexpected outcomes. At the level of the brain, learning rate modulation deficits may be associated with decreased involvement of the dmPFC within a greater RL network.

Depression and functioning are important to subjective quality of life after a first episode psychosis

BACKGROUND

Subjective quality of life (S-QoL) is an important outcome measure in first-episode psychosis, but its associations with clinical predictors may vary across the illness course. In this study we examine the association pattern, including both direct and indirect effects, between specific predefined clinical predictors (insight, depression, positive psychotic symptoms and global functioning) and S-QoL the first ten years after a first-episode psychosis.

METHODS

Three hundred and one patients with a first-episode psychosis were included at first treatment, and reassessed at 3 months, 1 year, 2 years, 5 years and 10 years after inclusion. At 10-year follow-up 186 participated. S-QoL was assessed with Lehman's Quality of Life Interview. Applying a structural equation model, we investigated cross-sectional association patterns at all assessments between the predefined clinical predictors and S-QoL.

RESULTS

At baseline, only depression was significantly associated with S-QoL. At all follow-up assessments, depression and functioning showed significant associations with S-QoL. Insight was not associated with S-QoL at any of the assessments. Better insight, less depressive symptoms and less positive psychotic symptoms were all associated with higher functioning at all assessments. Functioning seems to mediate a smaller indirect inverse association between positive psychotic symptoms and S-QoL. The association pattern was stable across all follow-up assessments.

CONCLUSIONS

Together with depression, functioning seems to be important for S-QoL. Functioning seems to be a mediating factor between positive symptoms and S-QoL. A focus on functional outcome continues to be important.

Association of neurocognitive deficits and insight in schizophrenia

AIM

To evaluate the relationship between neurocognitive deficits and insight (clinical & cognitive) among patients with schizophrenia in clinical remission.

METHODOLOGY

60 patients with schizophrenia (diagnosed as per the DSM-IV criteria) in clinical remission were assessed on Beck Cognitive Insight scale (BCIS), Positive and Negative symptom scale (PANSS) and neurocognitive battery (Trail A and B, Stroop Test, Controlled Oral Words Association (COWA) and Tower of London (TOL).

RESULTS

Lower processing speed, low cognitive flexibility and poor executive functions as assessed by Trail A, Trail B and TOL respectively and higher verbal fluency (COWA) were associated with poor cognitive insight in the self-certainty domain. Poor executive functioning (3 moves problem of TOL) was associated with lower cognitive insight in the domain of self-reflectiveness. Clinical insight as assessed by item number 12 of general psychopathology subscale of PANSS did not have any association with any of the neurocognitive domains except for few subsets of executive functions as assessed by TOL. There was no correlation between clinical insight and cognitive insight. However, many of these correlations were weak and could be due to Type-1 error as significance of correlation was fixed at two tailed 0.05 level. Multiple regression analysis demonstrated cognitive flexibility as assessed by Trail B test and executive functions (3 moves and 5 moves problems of TOL) to be the significant predictors of self-certainty and self- reflectiveness domains of the cognitive insight.

CONCLUSIONS

The present study suggests that poor cognitive flexibility and executive dysfunction are associated with poor cognitive insight but the impact of poor neurocognitions on the clinical insight is not very significant.

The error-related negativity (ERN) is an electrophysiological marker of motor impulsiveness on the Barratt Impulsiveness Scale (BIS-11) during adolescence

Objectives

Previous studies have postulated that the error-related negativity (ERN) may reflect individual differences in impulsivity; however, none have used a longitudinal framework or evaluated impulsivity as a multidimensional construct. The current study evaluated whether ERN amplitude, measured in childhood and adolescence, is predictive of impulsiveness during adolescence.

Methods

Seventy-five children participated in this study, initially at ages 7–9 years and again at 12–18 years. The interval between testing sessions ranged from 5 to 9 years. The ERN was extracted in response to behavioural errors produced during a modified visual flanker task at both time points (i.e. childhood and adolescence). Participants also completed the Barratt Impulsiveness Scale − a measure that considers impulsiveness to comprise three core sub-traits − during adolescence.

Results

At adolescence, the ERN amplitude was significantly larger than during childhood. Additionally, ERN amplitude during adolescence significantly predicted motor impulsiveness at that time point, after controlling for age, gender, and the number of trials included in the ERN. In contrast, ERN amplitude during childhood did not uniquely predict impulsiveness during adolescence.

Conclusions

These findings provide preliminary evidence that ERN amplitude is an electrophysiological marker of self-reported motor impulsiveness (i.e. acting without thinking) during adolescence.

Insight and major mental illness: an update for clinicians

This article will concentrate on insight into serious mental disorder. Not psychoanalytic insight – nor indeed, the insight all of us have, to a greater or lesser extent, into our own attitudes, motives and behaviour – but the insight which patients with psychosis have into their mental pathology. This is no longer considered an all-or-none phenomenon, but rather a dimensional one, so that subjects can have different levels of awareness into their illness. The suggestion was first mooted by Aubrey Lewis (1934) in his seminal work on insight. Conceptual exploration of insight has been activated in the past decade and is proceeding in parallel with the construction of special scales to measure insight and research into its cognitive, biological, social and cultural basis.

Narrative Structure in Psychosis

There is nearly universal acceptance that persons with schizo-phrenia often experience a profound disruption in their basic sense of self. But what does this disruption in sense of self reflect? Is this the result of an internal catastrophe? If so, where and in what manner did this catastrophe occur? To address these issues this paper will review various perspectives on disruptions of self-experience in schizophrenia as well as literature regarding how sense of self among people in general normally develops out of dialogues both within the individual and between the self and others. Following this we will theorize that the subjective experience of personal incoherence in schizophrenia may reflect a collapse of the ability to maintain ongoing dialogue within the self, specifically arguing that as internal dialogues evaporate, self-experience and personal narrative can devolve into one of three forms: (a) a barren and empty self-organization; (b) internal cacophony; or (c) self constructions dominated by rigid, non-evolving monologues. Lastly, implications for treatment and recovery will be discussed, including the potential usefulness of a focus on interventions that might revitalize clients' internal and external dialogue.

Characterizing a psychiatric symptom dimension related to deficits in goal-directed control

Prominent theories suggest that compulsive behaviors, characteristic of obsessive-compulsive disorder and addiction, are driven by shared deficits in goal-directed control, which confers vulnerability for developing rigid habits. However, recent studies have shown that deficient goal-directed control accompanies several disorders, including those without an obvious compulsive element. Reasoning that this lack of clinical specificity might reflect broader issues with psychiatric diagnostic categories, we investigated whether a dimensional approach would better delineate the clinical manifestations of goal-directed deficits. Using large-scale online assessment of psychiatric symptoms and neurocognitive performance in two independent general-population samples, we found that deficits in goal-directed control were most strongly associated with a symptom dimension comprising compulsive behavior and intrusive thought. This association was highly specific when compared to other non-compulsive aspects of psychopathology. These data showcase a powerful new methodology and highlight the potential of a dimensional, biologically-grounded approach to psychiatry research.

DOI:http://dx.doi.org/10.7554/eLife.11305.001

When an individual resists the temptation to stay out late in order to get a good night’s sleep, he or she is exercising what is known as “goal-directed control”. This kind of control allows individuals to regulate their behaviour in a deliberate manner. It is thought that a reduction in goal-directed control may be linked to compulsiveness or compulsivity, a psychological trait that involves excessive repetition of thoughts or actions. Furthermore, evidence shows that goal-directed control is reduced in people with compulsive disorders, such as obsessive-compulsive disorder (or OCD) and drug addiction. However, failures of goal-directed control have also been reported in other mental health conditions that are not linked to compulsivity, such as social anxiety disorder.

The fact that reduced goal-directed control is found across various mental health conditions highlights a core issue in modern psychiatric research and treatment. Mental health conditions are typically defined and diagnosed by their clinical symptoms, not by their underlying psychological traits or biological abnormalities. This makes it difficult to determine the cause of a specific disorder, as its symptoms are often rooted in the same psychological and biological traits seen in other mental health conditions.

To start to tackle this issue, Gillan et al. used a strategy that allowed them to look at compulsivity as a “trans-diagnostic dimension”; that is, as something that exists on a spectrum and is not specific to one disorder but involved in numerous different mental health conditions. Nearly 2,000 people completed an online task that assessed goal-directed control, and filled in questionnaires that measured symptoms of various mental health conditions. Gillan et al. showed that, as expected, people with reduced goal-directed control were generally more compulsive, and that this relationship could be seen in the context of both OCD and other compulsive disorders such as addiction.

Further, by leveraging the efficiency of online data collection to collect such a large sample, Gillan et al. were also able to examine how much different symptoms co-occurred in people. This enabled them to use a statistical technique to pick out three trans-diagnostic dimensions – compulsive behaviour and intrusive thought, anxious-depression and social withdrawal – and found that only the compulsive factor was associated with reduced goal-directed control. In fact, reduced goal-directed control was found to be more closely related to compulsivity than the symptoms of traditional mental health disorders including OCD. These findings show that research into the causes of mental health conditions and perhaps ultimately diagnosis and treatment – all of which have traditionally approached specific disorders in isolation – would benefit greatly from a trans-diagnostic approach.

DOI:http://dx.doi.org/10.7554/eLife.11305.002

Insight and neurocognitive functioning in bipolar subjects

BACKGROUND

Insight concerning having a mental illness has been found to influence outcome and effectiveness of treatment. It has been studied mainly in the area of schizophrenia with few studies addressing other disorders. This study evaluates insight in individuals with bipolar disorder using the Scale to Assess Unawareness of Mental Disorder (SUMD), a comprehensive interview for evaluation of awareness of illness and attribution of symptoms. The hypothesis was that in bipolar disorder level of awareness may be associated with numerous factors including neurocognitive function, structural changes in the frontal lobes and hippocampus evaluated by MRI, neurocognitive status, severity of mania and other psychiatric symptoms and comorbid alcoholism.

METHOD

In order to evaluate this hypothesis 33 individuals with DSM-IV diagnosed bipolar disorder, some with and some without comorbid alcoholism, were administered the SUMD and a number of other procedures including a quantitative MRI measuring volume of the frontal lobes and hippocampus, a brief battery of neurocognitive tests, the Brief Psychiatric Rating Scale, and the Young Mania Rating Scale. The data were analyzed by comparing participants with and without alcoholism on these procedures using t tests and by linear multiple regression, with SUMD ratings of awareness and attribution as the dependent variables and variable sets from the other procedures administered as multivariate independent variables.

RESULTS

The median score obtained from the SUMD for current awareness was in a range between full awareness and uncertainty concerning presence of a mental disorder. For attribution, the median score indicated that attribution was usually made to the illness itself. None of the differences between participants with and without comorbid alcoholism were significant for the SUMD awareness and attribution scores, neurocognitive or MRI variables. The multiple regression analyses only showed a significant degree of association between the SUMD awareness score and the Young Mania Rating Scale (r(2)=.632, p<.05). A stepwise analysis indicated that items assessing degree of insight, irritability, and sleep disturbance met criteria for entry into the regression equation. None of the regression analyses for the SUMD attribution item were significant.

CONCLUSIONS

Apparently unlike the case for schizophrenia, most of the participants, all of whom had bipolar disorder, were aware of their symptoms and correctly related them to a mental disorder. Hypotheses concerning the relationships between degree of unawareness and possible contributors to its development including comorbid alcoholism, cognitive dysfunction and structural reduction of gray matter in the frontal region and hippocampus, were not associated with degree of unawareness but symptoms of mania were significantly associated. The apparent reason for this result is that the sample obtained a SUMD modal awareness score of 1 or 2, reflecting the area between full awareness and uncertainty about having a mental disorder. None of the participants were rated as having a 5 response reflecting the belief that s/he does not have a mental disorder.

Insight in psychotic disorder: relation with psychopathology and frontal lobe function

BACKGROUND/AIMS

Through conceptualising poor insight in psychotic disorders as a form of anosognosia, frontal lobe dysfunction is often ascribed a vital role in its pathogenesis. The objective of this study was to compare the relation of insight in patients with psychotic illness to that of psychopathology and frontal lobe function.

METHODS

Forty patients with psychotic disorder were selected from those attending the Department of Psychiatry in a tertiary care teaching hospital. The evaluation of insight was carried out using the Schedule for Assessment of Insight (SAI), that of frontal lobe function by the Frontal Assessment Battery (FAB) and psychopathology by the Brief Psychiatric Rating Scale (BPRS). The correlation coefficients were determined.

RESULTS

A negative correlation between SAI and BPRS scores means that the BPRS score is opposite to SAI scores. When the SAI total score was compared with the FAB total score, the correlation coefficient demonstrated a positive correlation. Better insight predicted lesser psychopathology and also that poor insight would exist with greater psychopathology. Better insight predicted a higher functional status of frontal lobes and prefrontal cortex in particular.

CONCLUSION

Insight deficits in schizophrenia and other psychotic illnesses are multidimensional. Integration of different aetiological factors like biological, psychopathological, environmental ones and others are necessary for a better understanding of insight in psychosis.

Insight into illness in late-life schizophrenia: a function of illness severity and premorbid intellectual function

Impaired insight into illness is a common but poorly understood phenomenon in schizophrenia. Several studies in midlife adults with schizophrenia have reported an association between impaired insight and illness severity, executive dysfunction, premorbid intellectual function, and to a lesser degree attention. Aging is associated with a decline in attention and executive function. Thus, the relationship between cognition and insight is expected to differ between younger and older adults with schizophrenia. This study assessed this relationship among 50 patients with schizophrenia 60 years and older. Insight was explained by illness severity (16.2% of the variance) and premorbid intellectual function (23.9% of the variance), but not by attention or executive function. Our findings suggest that the predictors of insight in schizophrenia differ early and later in life. In particular, insight's association with attention and executive function observed in younger patients is attenuated by age-related changes in cognition. In contrast, premorbid intellectual function continues to be a strong predictor of insight in late life, which highlights the need to better understand and enhance cognitive function early in the course of schizophrenia.

Association between cognitive insight and prefrontal function during a cognitive task in schizophrenia: a multichannel near-infrared spectroscopy study

Insight has been studied mostly from a clinical perspective. Recently, the focus of this research field shifted to cognitive insight or the ability to monitor and correct the erroneous convictions of individuals. In this study, we investigated the relationship between cognitive insight and prefrontal function during a cognitive task in 30 patients with clinically stable schizophrenia and 30 age- and gender-matched healthy controls. We measured the changes in hemoglobin concentration in the prefrontal and temporal cortical regions during a verbal fluency task (VFT) by using 52-channel near-infrared spectroscopy (NIRS). Cognitive insight was measured using the Beck Cognitive Insight Scale (BCIS). Regional hemodynamic changes were significantly smaller in the schizophrenia group than in the control group in prefrontal and temporal regions, and significant positive relationship was observed between the score of the BCIS self-reflectiveness subscale and right ventrolateral prefrontal and right temporal functions during the VFT. These results suggest that the right ventrolateral prefrontal and temporal cortical regions are associated with cognitive insight in clinically stable patients with schizophrenia and that NIRS is an efficient medical tool for monitoring these characteristics.

Insight in stable schizophrenia: relations with psychopathology and cognition

OBJECTIVE

This study evaluated the relationship among insight, sociodemographic and clinical variables, symptoms and cognitive functions in a population of outpatients with stable schizophrenia, in order to identify possible contributing factors to awareness.

METHOD

Two-hundred and seventy-six consecutive outpatients with stable schizophrenia were enrolled in a cross-sectional study. All subjects were assessed by psychiatric scales and interview, and a wide neuropsychological battery. A factor analysis was performed to identify cognitive factors and multiple regression analyses were executed to test the contribution of variables considered to insight.

RESULTS

Our results showed that positive and negative symptoms, executive functions, verbal memory-learning were contributors of awareness of mental illness; positive and negative symptoms explained variability in awareness of the need for treatment; positive symptoms and executive functions contributed to awareness of the social consequences of disorder.

CONCLUSIONS

These results suggested that insight was partially influenced by positive and negative symptoms and by cognitive functions. A complex system of overlapping variables may underlie impaired insight, contributing to a different extent to specific dimensions of poor insight in patients with stable schizophrenia.

Brain structural changes and neuropsychological impairments in male polydipsic schizophrenia

BACKGROUND

Polydipsia frequently occurs in schizophrenia patients. The excessive water loading in polydipsia occasionally induces a hyponatremic state and leads to water intoxication. Whether polydipsia in schizophrenic patients correlates with neuropsychological impairments or structural brain changes is not clear and remains controversial.

METHODS

Eight polydipsic schizophrenia patients, eight nonpolydipsic schizophrenia patients, and eight healthy controls were recruited. All subjects underwent magnetic resonance imaging (MRI) and neuropsychological testing. Structural abnormalities were analyzed using a voxel-based morphometry (VBM) approach, and patients' neuropsychological function was assessed using the Brief Assessment of Cognition in Schizophrenia, Japanese version (BACS-J).

RESULTS

No significant differences were found between the two patient groups with respect to the clinical characteristics. Compared with healthy controls, polydipsic patients showed widespread brain volume reduction and neuropsychological impairment. Furthermore, the left insula was significantly reduced in polydipsic patients compared with nonpolydipsic patients. These nonpolydipsic patients performed intermediate to the other two groups in the neuropsychological function test.

CONCLUSIONS

It is possible that polydipsia or the secondary hyponatremia might induce left insula volume reduction. Furthermore, this structural brain change may indirectly induce more severe neuropsychological impairments in polydipsic patients. Thus, we suggest that insula abnormalities might contribute to the pathophysiology of polydipsic patients.

Empirically defined patterns of executive function deficits in schizophrenia and their relation to everyday functioning: a person-centered approach

Executive function (EF) deficits in schizophrenia (SZ) are well documented, although much less is known about patterns of EF deficits and their association to differential impairments in everyday functioning. The present study empirically defined SZ groups based on measures of various EF abilities and then compared these EF groups on everyday action errors. Participants (n = 45) completed various subtests from the Delis-Kaplan Executive Function System (D-KEFS) and the Naturalistic Action Test (NAT), a performance-based measure of everyday action that yields scores reflecting total errors and a range of different error types (e.g., omission, perseveration). Results of a latent class analysis revealed three distinct EF groups, characterized by (a) multiple EF deficits, (b) relatively spared EF, and (c) perseverative responding. Follow-up analyses revealed that the classes differed significantly on NAT total errors, total commission errors, and total perseveration errors; the two classes with EF impairment performed comparably on the NAT but performed worse than the class with relatively spared EF. In sum, people with SZ demonstrate variable patterns of EF deficits, and distinct aspects of these EF deficit patterns (i.e., poor mental control abilities) may be associated with everyday functioning capabilities.

Insight in bipolar disorder

Although there has been interest in insight in bipolar disorder, research has not been as developed as in schizophrenia. The Medline, Embase, and PsychInfo data bases were searched. The key words used in the search were "bipolar", "mania", "manic", "awareness", and "insight". Books, editorials, letters, and reports on pediatric subjects were excluded. Abstracts or full texts were screened for relevance. Better insight is associated with better adherence to treatment and better outcomes. Impairments of executive functions and memory, as well as higher severity of psychotic symptoms, are associated with impairments of insight. Insight is more impaired during an illness episode than during remission, in mixed than in pure manic episodes, in bipolar II than in bipolar I patients, in pure mania than in bipolar or unipolar depression. Psychosocial treatments improve insight and outcomes. There is a need for integration of quantitative assessment methods and their introduction into research and clinical practice.

Preserved cognitive function is associated with suicidal ideation and single suicide attempts in schizophrenia

OBJECTIVE

Suicide is the leading cause of death in schizophrenia. An association between suicidal behavior and both higher and lower cognitive ability in schizophrenia has been reported. To clarify this relationship, we investigated whether the relationship between suicidality and neurocognition varied according to differences in suicidal ideation and behavior.

METHODS

Three hundred and ten patients with DSM-IV diagnoses of schizophrenia or schizoaffective disorder were categorized based on patient and staff interviews as either non-suicide attempters, non-attempters expressing suicidal ideation, single suicide attempters, or multiple suicide attempters. These groups were compared on a neuropsychological battery examining current general cognitive ability, episodic and working memory, and attentional control.

RESULTS

Neuropsychological performance in those with a history of suicidal ideation (n=63), and those who had made one suicide attempt (n=48) was comparable. Together, these groups outperformed patients with no history of either suicidal behavior or ideation (n=172) on measures of IQ, episodic memory and working memory. Only differences in global cognition remained significant after controlling for between-group differences in depressive symptoms. Those who had either expressed suicidal ideation and/or made a single suicide attempt demonstrated trend level advantages in neuropsychological tests over those that had made multiple suicide attempts.

DISCUSSION

These findings support earlier evidence of an association between suicidality and neurocognitive ability in schizophrenia. Specifically, these data suggest that patients who have contemplated suicide or made a single suicide attempt have better cognitive functioning than those who have not. Suicidality in multiple attempters, who do not perform better in neurocognitive tests than those who have neither contemplated nor attempted suicide, is likely to be influenced by factors other than neurocognitive ability.

Insight in schizophrenia: from conceptualization to neuroscience

Lack of insight into illness is a prevalent and distinguishing feature of schizophrenia, which has a complex history and has been given a variety of definitions. Currently, insight is measured and treated as a multidimensional phenomenon, because it is believed to result from psychological, neuropsychological and organic factors. Thus, schizophrenia patients may display dramatic disorders including demoralization, depression and a higher risk of suicide, all of which are directly or indirectly related to a lack of insight into their illness, and make the treatment difficult. To improve the treatment of people with schizophrenia, it is thus crucial to advance research on insight into their illness. Insight is studied in a variety of ways. Studies may focus on the relationship between insight and psychopathology, may view behavioral outcomes or look discretely at the cognitive dysfunction versus anatomy level of insight. All have merit but they are dispersed across a wide body of literature and rarely are the findings integrated and synthesized in a meaningful way. The aim of this study was to synthesize findings across the large body of literature dealing with insight, to highlight its multidimensional nature, measurement, neuropsychology and social impact in schizophrenia. The extensive literature on the cognitive consequences of lack of insight and the contribution of neuroimaging techniques to elucidating neurological etiology of insight deficits, is also reviewed.

Gray matter volume deficits and correlation with insight and negative symptoms in first-psychotic-episode subjects

OBJECTIVE

To determine brain areas reduced in first episode of psychotic subjects and its association with lack of insight and negative symptoms.

METHOD

Twenty-one drug naive first-episode subjects and 20 controls underwent a structural MRI scan and were clinically assessed. Optimized voxel-based-morphometry analysis (VBM) was implemented to find between-group differences and correlations between GM volume and: (i) lack of insight and (ii) negative symptoms.

RESULTS

Patients showed GM reduction in prefrontal and left temporal areas. A significant correlation was found between insight and GM volume in the cerebellum (corrected P = 0.01), inferior temporal gyrus (corrected P = 0.022), medial superior frontal gyrus (corrected P < 0.001), and inferior frontal gyrus (corrected P = 0.012), as the insight decreased, the volume decreased. Negative symptoms correlated with decreased GM volume at cerebellum (corrected P = 0.037) and frontal inferior regions (corrected P < 0.001), the more negative symptoms, the less volume.

CONCLUSION

Our findings support an association between prefrontal, temporal, and cerebellar deficits and lack of insight in schizophrenia and confirm previous findings of GM deficits in patients since the first episode of psychosis.

White matter integrity and lack of insight in schizophrenia and schizoaffective disorder

OBJECTIVE

Poor insight into illness is commonly associated with schizophrenia and has implications for the clinical outcome of the disease. A better understanding of the neurobiology of these insight deficits may help the development of new treatments targeting insight. Despite the importance of this issue, the neural correlates of insight deficits in schizophrenia remain poorly understood.

METHOD

Thirty-six individuals diagnosed with schizophrenia or schizoaffective disorder underwent diffusion tensor imaging (DTI). The subjects were assessed on two dimensions of insight (symptom awareness and attribution of symptoms) using the Scale to Assess Unawareness of Mental Disorder (SUMD). Level of psychosis was assessed with the Positive and Negative Syndrome Scale (PANSS).

RESULTS

White matter abnormalities in the right superior frontal gyrus, left middle frontal gyrus, bilateral parahippocampal gyrus, adjacent to the right caudate head, right thalamus, left insula, left lentiform nucleus, left fusiform gyrus, bilateral posterior cingulate, left anterior cingulate, right cingulate gyrus, left lingual gyrus, and bilateral claustrum were associated with symptom unawareness. Misattribution of symptoms was related to deficits in the white matter adjacent to the right lentiform nucleus, left middle temporal gyrus, and the right precuneus.

CONCLUSIONS

Impaired insight in schizophrenia implicates a complex neural circuitry: white matter deficits in fronto-temporo brain regions are linked to symptom unawareness; compromised temporal and parietal white matter regions are involved in the misattribution of symptoms. These findings suggest the multidimensional construct of insight has multiple neural determinants.

Subjective awareness of everyday dysexecutive behavior precedes 'objective' executive problems in schizotypy: a replication and extension study

This study aimed to examine the subjective awareness of everyday dysexecutive function and the 'objective' executive function in individuals with schizotypal personality features. Forty-nine individuals with schizotypal personality disorder (SPD) proneness (25 negative schizotypy and 24 non-negative schizotypy were identified using cluster analysis) and 44 non-SPD individuals completed a battery of 'objective' executive function tests and a self-reported Dysexecutive Questionnaire (DEX) on everyday executive problems. The findings showed that individuals with SPD proneness including negative schizotypy and non-negative schizotypy did not have significant worse performance than non-SPD in most of 'objective' executive function tests, but self-reported significantly disproportionate more dysexecutive problems than non-SPD. Furthermore, SPD proneness, especially negative schizotypy was found to give undependable estimation on their everyday dysexecutive function while non-negative schizotypy was not. The current findings suggest that the subjective awareness of dysexecutive function may precede actual 'objective' executive function impairments in a subtype of SPD (non-negative schizotypy) and the subjective complaint of the daily dysexecutive behavior in SPD proneness, especially negative schizotypy might result from their unreliable estimation of executive function.

Deficits in fronto-posterior interactions point to inefficient resource allocation in schizophrenia

OBJECTIVE

Fronto-posterior networks have been implicated in various cognitive processes that are impaired in schizophrenia. This is the first study on time and frequency resolved fronto-posterior coherence during cognitive control in schizophrenia.

METHOD

We examined 16 schizophrenic/schizoaffective patients and 20 age-matched controls performing a choice-reaction task. Fronto-posterior coherence was analyzed for event-related increases with respect to the inter-trial interval. Furthermore, we compared the two groups for event-related coherence during the task-related time intervals which showed a significant coherence increase with respect to the inter-trial interval, as well as for absolute coherence during the inter-trial interval.

RESULTS

Event-related coherence was significantly reduced in patients during time intervals (0-250 ms poststimulus) when controls showed significant event-related coherence increases. However, patients showed significantly higher absolute coherence during the inter-trial interval. These results pointed to differential deficits in fronto-posterior connectivity during the inter-trial interval and task-related conditions in schizophrenia.

CONCLUSION

Cognitive deficits in schizophrenia might be driven by abnormal fronto-posterior communication. Task-related hypo-connectivity and inter-trial interval hyper-connectivity point to resource allocation deficits. The timing of cortico-cortical interactions during crucial task-related intervals may be impaired, while frontal and posterior areas may exhibit increased interactions between the trials.

Trait and state attributes of insight in first episodes of early-onset schizophrenia and other psychoses: a 2-year longitudinal study

BACKGROUND

Increasing evidence supports the important role of illness state and individual characteristics in insight.

METHODS

Insight, as measured with the Scale to Assess Unawareness of Mental Disorder, over the first 2 years of early-onset first-episode psychosis and its correlations with clinical, socio-demographic, cognitive, and structural brain variables are studied.

RESULTS

(1) insight at 2 years is poorer in schizophrenia spectrum disorders (SSDs) than in subjects with other psychoses; (2) the more severe the psychosis, the worse the insight. In SSD, depressive symptoms, poorer baseline executive functioning, lower IQ, longer duration of untreated psychosis (DUP), and poorer premorbid infancy adjustment are associated with poorer insight; frontal and parietal gray matter (GM) reductions at baseline correlate with worse insight into having psychotic symptoms at 2 years; (3) insight into having a mental disorder (Scale to Assess Unawareness of Mental Disorder [SUMD]1) at 1 year, DUP, and baseline IQ are the most consistent variables explaining different aspects of insight at 2 years in SSD patients. IQ and SUMD1 at 1 year, together with left frontal and parietal GM volumes, explain 80% of the variance of insight into having specific psychotic symptoms in SSD patients (adjusted R(2) = 0.795, F = 15.576, P < .001).

CONCLUSION

Insight is a complex phenomenon that depends both on severity of psychopathology and also on disease and subject characteristics, such as past adjustment, IQ, DUP, cognitive functioning, frontal and parietal GM volumes, and age, gender, and ethnicity.

The clinical applicability of the Self-Appraisal of Illness Questionnaire (SAIQ) to chronic schizophrenic patients in Taiwan

Over the last decade, several self-report instruments to assess insight of illness from schizophrenic patients' perspectives have been administered. The main purpose of this study was to ascertain the reliability and validity of the Taiwanese version of the Self-Appraisal of Illness Questionnaire (SAIQ) in a chronic schizophrenic sample in Taiwan. This scale is a self-administered instrument designed to evaluate attitudes toward mental illness among patients receiving treatment. In the current cross-sectional study, 104 patients who met DSM-IV criteria for schizophrenic disorders were recruited and independently interviewed. The psychometric properties of the translated SAIQ were determined, including internal consistency, test-retest reliability, and construct validity. In addition, we analyzed psychosocial and clinical characteristics as correlates of the Taiwanese version of the SAIQ. Overall, the Taiwanese version of the SAIQ was found to be internally consistent and reliable over time. This translated scale comprised a three-factor solution with factors corresponding to worry, the need for treatment, and presence/outcome subscales. The results also indicated that the three subscales and its total score were significantly associated with both the research-rated insight scale and psychopathology and mood state. This culture-specific study shows that the Taiwanese version of the SAIQ is a simple and reliable scale for use.

Impaired error awareness and anterior cingulate cortex hypoactivity in chronic cannabis users

Drug abuse and other psychiatric conditions (eg, schizophrenia) have been associated with a diminished neural response to errors, particularly in the anterior cingulate cortex (ACC) thought critical to error processing. A diminished capacity for detecting errors has been linked to clinical symptoms including the loss of insight, delusions, and perseverative behavior. A total of 16 active chronic cannabis users and 16 control participants were administered a Go/No-go response inhibition task during event-related fMRI data collection. The task provides measures of inhibitory control and error awareness. Cannabis users' inhibitory control performance was equivalent to that of the control group, but the former showed a significant deficit in awareness of commission errors. Cannabis users showed a diminished capacity for monitoring their behavior that was associated with hypoactivity in the ACC and right insula. In addition, increased levels of hypoactivity in both the ACC and right insula regions were significantly correlated with error-awareness rates in the cannabis group (but not controls). These difficulties are consistent with earlier reports of hypoactivity in the neural systems underlying cognitive control and the monitoring of interoceptive awareness in chronic drug users, and highlight the potential relationship between cognitive dysfunction and behavioral deficits that have the potential to contribute to the maintenance of drug abuse.

Reduced insight in bipolar I disorder: neurofunctional and neurostructural correlates: a preliminary study

BACKGROUND

To correlate measures of insight for own psychopathology to structural and functional brain imaging findings in 21 patients with DSM-IV bipolar I disorder.

METHODS

Insight was assessed using the Scale to Assess Unawareness of Mental Disorder (SUMD). Resting single photon emission computed tomography (SPECT) and computed tomography (CT) was conducted in patients and 21 normal comparison subjects matched for age, gender and handedness.

RESULTS

Reduced general insight and symptom awareness, but not symptom attribution, were significantly related to cortical and subcortical atrophy, respectively. No correlations between SPECT and insight measures were identified.

LIMITATIONS

Limited sample size and the use of resting state SPECT.

CONCLUSIONS

General and symptom awareness were related to measures of brain atrophy but not to neurofunctioning as measured by SPECT. Future research should consider the structure and function of specific cortical regions, including the frontal and parietal cortices.

Executive functions and cognitive deficits in schizophrenia: comparisons between probands, parents and controls in India

BACKGROUND

Cognitive impairment is said to be a core feature of schizophrenia. Executive function is an important cognitive domain.

AIM

This study was undertaken to assess cognitive impairment among Indian patients with schizophrenia (Sz) or schizoaffective disorder (SzA), compared with their parents and unaffected individuals (controls).

SETTINGS AND DESIGN

Executive functions as measured by Trail-making Test (TMT), of patients and their parents were compared with controls. The patients were recruited from the Outpatients' Department (OPD) of a government hospital.

MATERIALS AND METHODS

Patients diagnosed as Sz or SzA (n=172) and their parents (n=196: families n=132, 119 fathers and 77 mothers) participated. We also included 120 persons with no history of psychiatric illness. Cognitive function was assessed with the TMT. The Information Score of the Post Graduate Institute Battery of Brain Dysfunction test, developed in India for Indian subjects was used as a proxy for general fixed knowledge.

STATISTICAL ANALYSIS

Logistic and linear regression was used to compare cognitive deficits of cases, parents and controls.

RESULTS

Cases and their parents took significantly more time than controls on Part B of the TMT. There were no statistically significant differences between cases and parents on any of the TMT parameters. Using regression analysis, the most significant correlates of all TMT parameters among cases were with occurrence of auditory hallucinations and current age.

CONCLUSION

Cases, as well as their parents showed more cognitive impairment than controls on the TMT.

Relationship between psychosocial adjustment and executive function in patients with bipolar disorder and schizophrenia in remission: the mediating and moderating effects of insight

OBJECTIVES

The aims of this study were to examine the relationships between executive function and psychosocial adjustment, and the mediating and moderating effects of insight on the association between executive function and psychosocial adjustment in patients with bipolar disorder and schizophrenia in clinical remission.

METHODS

The level of psychosocial adjustment was assessed in 96 subjects with bipolar disorder and 96 subjects with schizophrenia who were in remitted state. The association between executive function and psychosocial adjustment and the mediating and moderating effects of insight were examined by multiple regression analysis models and the Goodman test.

RESULTS

The results indicated that executive function had direct effect on psychosocial adjustment in both subjects with bipolar disorder and schizophrenia. However, the mediating effect of insight on the association between executive function and psychosocial adjustment was only found in subjects with schizophrenia, but not in subjects with bipolar disorder. No moderating effect of insight on the association between executive function and psychosocial adjustment was found in subjects with schizophrenia or bipolar disorder.

CONCLUSIONS

The results of this study indicated that executive function has an important role in psychosocial adjustment in both patients with bipolar disorder and schizophrenia. Meanwhile, insight has a different role in the association between executive function and psychosocial adjustment between patients with bipolar disorder and schizophrenia.

Insight, cognitive dysfunction and symptomatology in schizophrenia

Lack of insight is frequent in schizophrenia and usually influences negatively both patient's treatment and prognosis. This study aimed to investigate the relationship between insight, symptomatology and cognitive dysfunctions in schizophrenia using the PANSS five-factor model (modified from Gaag et al. in Schizophr Res 85:280-287, 2006). Forty patients diagnosed with chronic schizophrenia (DSM-IV) were evaluated with the scale to assess unawareness of mental disorder (SUMD), the PANSS and a neuropsychological battery. Spearman correlation and linear regression analyses were performed to investigate the relationship between clinical, neurocognitive and insight measures. The SUMD current and past awareness of symptoms score showed a correlation with WCST indices (correct answers and non-persevering errors). The negative and disorganization factor of the PANSS showed a positive correlation with current and past awareness of symptoms. However, when submitted to a linear regression model only the disorganization factor emerged as significant contributor for insight. Considering that the core items of the "disorganization factor" of the PANSS are related to cognition (e.g., poor attention, difficult in abstract thinking), insight is associated cognitive symptoms although no direct relationship between insight and neuropsychological tests was observed.

Relationship between insight and neurocognition in patients with bipolar I disorder in remission

The aim of this study was to examine the relationships between insight and neurocognition in a population of patients with bipolar I disorder who were in a remitted state. Using the Schedule of Assessment of Insight (SAI) and its expanded version, we evaluated 96 patients with bipolar I disorder in remission to determine their level of insight. We also evaluated their neurocognitive function included in the domains of executive function, attention, and memory. The associations between insight and neurocognitive function were examined by using the stepwise multiple regression analysis to control the confounding effects of sociodemographic and clinical factors. The results indicated that by controlling the confounding effects of other factors, executive function was positively associated with the SAI dimensions of awareness of illness and relabeling of phenomena, and the total expanded version of the SAI in remitted bipolar patients. The results of this study indicated that the relationships vary between different dimensions of insight and domains of neurocognitive function in remitted bipolar patients.

Suicidality and its association with insight and neurocognition in taiwanese patients with bipolar I disorder in remission

The aims of this study were to examine the relationships between suicidality, insight, and neurocognition in patients with bipolar I disorder who were in a remitted state. Using the Violence and Suicide Assessment Scale, we evaluated 96 patients with bipolar I disorder in remission to determine their suicidal ideations and attempts over the previous year. We also evaluated their level of insight by using the Schedule of Assessment of Insight (SAI) and its expanded version (SAI-E), as well as their neurocognitive function by a series of neurocognitive function tests. Insight and neurocognitive functions of bipolar subjects who had and who had no suicidal ideations or attempts over the previous year were compared. The results indicated that the remitted bipolar subjects who had suicidal ideations or attempts over the previous year had higher insight scores on all 3 SAI dimensions and on the SAI-E compared with those who had no suicidal ideations or attempts. However, no difference in any neurocognitive function was found between the 2 groups of remitted bipolar subjects. The results of this study suggest clinicians need to be particularly alert to the potential for suicide in bipolar patients with a high level of insight.

Effects of repeated dizocilpine treatment on adult rat behavior after neonatal lesions of the entorhinal cortex

Disturbed cortical development is implicated in some psychiatric diseases, e.g. in schizophrenia. Additionally, N-methyl-d-aspartate (NMDA) receptor antagonists like ketamine or phencyclidine have been reported to exacerbate schizophrenic symptoms. We here investigated the effects of neonatal entorhinal cortex (EC) lesions on adult rat behavior before and after repeated high-dose treatment with the NMDA antagonist dizocilpine, in order to combine these etiopathogenetical factors in an animal model. Bilateral neonatal (postnatal day 7) lesions were induced by microinjection of ibotenic acid (1.3 microg/0.2 microl PBS) into the EC. Naive and sham-lesioned rats served as controls. Adult rats were tested for behavioral flexibility on a cross maze, for locomotor activity in the open field and for sensorimotor gating using prepulse inhibition (PPI) of startle. Rats were then treated with dizocilpine (0.5 mg/kg b.i.d. for 7 days) and retested 1 week after withdrawal using the same behavioral tests as before. PPI was additionally measured after acute low-dose challenge with dizocilpine (0.15 mg/kg). EC lesions reduced behavioral flexibility as shown by impaired switching between spatial (allocentric) and non-spatial (egocentric) maze strategies. High-dose dizocilpine treatment disturbed switching to the egocentric strategy in all groups, which added to the effect of EC lesions. Neonatal EC lesions did not alter locomotor activity or PPI, but high-dose dizocilpine treatment reduced motor activity of all groups without changing PPI. The combination of neonatal EC lesions and adult dizocilpine treatment does not lead to super-additive effects on behavior. However, both treatments may serve to model certain aspects of psychiatric symptoms.

Relationships between insight and psychosocial adjustment in patients with bipolar I disorder

OBJECTIVES

The aim of this cross-sectional study was to examine the relationships between insight and psychosocial adjustment in outpatients with bipolar I disorder in clinical remission.

METHODS

Using the Schedule of Assessment of Insight (SAI) and its expanded version (SAI-E), we evaluated 50 consecutive patients with bipolar I disorder in remission to determine their level of insight. We also evaluated their psychosocial adjustment using the Community Life Scale. Relationships among psychosocial adjustment, insight, residual affective symptoms, and demographic and clinical characteristics were examined.

RESULTS

The results of the multiple regression analysis indicated that having a higher total SAI or SAI-E insight score and having no residual affective symptoms were significantly associated with better psychosocial adjustment in patients with bipolar I disorder.

CONCLUSIONS

In this cross-sectional study, better insight and less residual affective symptoms were correlated with good psychosocial adjustment. To address the causality issue, a longitudinal study is needed.

Clinical and neuropsychological correlates of insight in schizophrenia and bipolar I disorder: does diagnosis matter?

BACKGROUND

Lack of insight is a well-recognized feature of schizophrenia and is associated with symptom severity and cognitive impairments. However, the diagnostic specificity of insight variables and their correlates is not known. To assess this specificity, we compared awareness of illness and neuropsychological function between patients with chronic schizophrenia and bipolar I disorder.

METHOD

We assessed insight, level of psychopathology, and cognitive performance on a neuropsychological test battery in 37 patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition bipolar I disorder, 32 patients with schizophrenia, and 31 healthy subjects for comparison.

RESULTS

There was no significant difference between the 2 diagnostic groups on general illness awareness. However, patients with bipolar disorder had better awareness of their symptoms and their pathologic nature compared to patients with schizophrenia. Similar patterns of association emerged between insight and clinical variables. General unawareness was associated with clinical severity, especially of the affective type, and working memory deficits (Wechsler Adult Intelligence Scale digit span) in both diagnostic groups. The contribution of other cognitive deficits to insight differed across the groups. Misattribution differed from the other aspects of insight in its relative independence of clinical and neurocognitive correlates. Both patient groups were neurocognitively impaired, with the schizophrenia group performing significantly worse on conceptual ability, verbal learning, visuospatial processing, and motor speed.

CONCLUSIONS

The results suggest that differences in general insight in major mental disorders may be explained by symptom severity and working memory function rather than the specific diagnosis. Subcomponents of insight are influenced by different factors emphasizing the need to consider insight as multidimensional.

Selective breeding for deficient sensorimotor gating is accompanied by increased perseveration in rats

Prepulse inhibition (PPI) of the acoustic startle response is a measure of sensorimotor gating that is deficient in some neuropsychiatric disorders, such as schizophrenia and Tourette's syndrome. Experimentally induced PPI deficits in rats are regarded as endophenotype to study the biological mechanisms and therapeutic strategies of these disorders. We have recently shown that selectively breeding rats for high and low PPI levels, respectively, leads to groups with different PPI performance that remains stable from the second generation on. We here tested whether the low PPI is accompanied by other behavioral deficits. Different spatial and operant learning paradigms were used to assess rats' learning and memory abilities as well as their behavioral flexibility. In the delayed alternation T-maze task the two groups did not differ in task acquisition and working memory. Rats with low PPI showed enhanced perseveration during switching between an egocentric and allocentric radial maze task. Enhanced perseveration was also found in an operant behavioral task, where different demands, i.e. a different number of lever presses for a pellet-reward, were assigned to and switched between two levers of a Skinner box. Rats with low PPI stayed longer at the ineffective lever before switching, thus being less able to adjust their behavior to changing reward values. Additionally, PPI low rats had a higher breakpoint value during a progressive ratio-schedule of reinforcement. Rats selectively bred for low PPI showed some cognitive deficits that are apparent in a number of psychiatric disorders with deficient information processing. Specifically in both, spatial and operant behavioral paradigms, PPI low rats are deteriorated in their ability to modulate behavior based upon new changing information. They may thus provide a non-pharmacological model that can be used to evaluate new therapeutic strategies ranging from pharmacological treatment to functional neurosurgery.

Neurobiological underpinnings of insight deficits in schizophrenia

Impaired insight into illness is commonly observed across various psychiatric illnesses, but is most frequent in patients with schizophrenia. The clinical relevance and public health impact of poor insight is reflected by its close association with important clinical outcome measures, such as treatment non-adherence, lower psychosocial functioning, poor prognosis, involuntary hospitalization, and higher utilization of emergency services. Although the neurobiology of insight has not been determined, data from neurocognitive and a few structural imaging studies provide some understanding of the neurobiological underpinnings of insight function in schizophrenia. Using published and preliminary data, we propose a hypothetical model of insight that may help initiate neurobiological investigations in this complex area.

Assessing the relationship between insight and everyday executive deficits in schizophrenia: a pilot study

Past research has found that deficits in insight into illness are related to executive deficits in schizophrenia. This study further explores this relationship with the utilization of an ecologically-valid battery of executive tests. The study included 21 patients with schizophrenia who were administered the Behavioural Assessment of the Dysexecutive Syndrome (BADS) and the first three items of the Scale to Assess Unawareness of Mental Disorder. Patients were found to be impaired on the BADS and most had insight into their illness. Lack of illness awareness was not significantly correlated with all of the BADS subtests with the exception of Rule Shift Cards, a measure of cognitive flexibility. The relationship between some measures of unawareness and Rule Shift Cards was still significant or approaching significance when the effects of IQ were partialled out. These findings add to previous research by demonstrating that cognitive flexibility, specifically involving the ability to shift set, is associated with awareness of illness in schizophrenia. On the other hand, it is proposed that most of the other BADS subtests are more complex and multifactorial, thereby making it difficult to find any associations that may exist between a specific subdimension of executive function and insight into illness.

Are self-reports valid for schizophrenia patients with poor insight? Relationship of unawareness of illness to psychological self-report instruments

This investigation aimed to determine whether impaired insight influences the validity of self-report test scores in schizophrenia and schizoaffective disorder. 274 outpatients enrolled in work rehabilitation completed the Beck Depression Inventory (BDI), Eysenck Personality Questionnaire (EPQ), Bell Object Relations and Reality Testing Inventory (BORRTI), and NEO-Five Factor Inventory (NEO-FFI). Self-report scores were compared to clinician's ratings on comparable personality and symptom dimensions on the Positive and Negative Syndrome Scale (PANSS), the Work Behavior Inventory (WBI), and the Quality of Life Scale (QLS). The influence of insight was determined using the Scale for Unawareness of Mental Disorder (SUMD). In the first analysis, clinician SUMD ratings of patient insight were associated with self-report accuracy. In a second analysis, patients were categorized into good and poor insight groups based on SUMD ratings and compared on self-report and clinician report variables. Results suggest that poor insight patients accurately report less Neuroticism and Agreeableness, and more Psychoticism than good insight patients, but individuals with poor insight wish to present themselves as more extraverted than they actually are, and they are likely to be more certain of their perceptions than they should be. It appears that self-report measures may be valid for most personality and symptom domains.

Insight and psychopathology in never-treated schizophrenia

Insight is a feature of schizophrenia related to psychopathology, which could be modified by treatment. The real relationship will be more evident in the never-treated state. This study compared insight and its relationship to psychopathology in 143 never-treated patients with chronic schizophrenia with 183 treated patients. The treated patients had not received any structured intervention for improvement of insight. The item on insight and judgment from the Positive and Negative Syndrome Scale for schizophrenia was used as a measure of insight. Never-treated patients were more ill and poorer in insight than the TT group. Sex, age, duration of illness, negative symptoms related to insight only in the TT group. Positive symptoms score correlated with insight in both the groups, but negative symptoms correlated with insight only among the treated patients. Delusions, uncooperativeness, and poor attention predicted 27% of variation in the level of insight in the never-treated, whereas age; duration of illness; and symptoms of emotional withdrawal, difficulty in abstract thinking, and uncooperativeness predicted 30.3% of variation in insight of the TT group. The observed differences between the never-treated and treated subjects were due to influence of treatment on the association between insight and psychopathology. A subgroup of patients with a treatment-resistant trait of negative symptoms associated with poor insight was hypothesized.

Changes in insight among patients with bipolar I disorder: a 2-year prospective study

OBJECTIVES

The aim of this 2-year prospective study was to examine changes in insight among bipolar patients with different clinical courses.

METHODS

A cohort of 65 patients with bipolar I disorder in remission was recruited for this study. They received six follow-up assessments over a 2-year period. The Schedule of Assessment of Insight-Expanded version (SAI-E) was used to determine their levels of insight, while the Young Mania Rating Scale (YMRS) and the Hamilton Rating Scale for Depression (HAM-D) were used to determine affective symptoms. Types of changes in insight among bipolar patients were analyzed according to the different clinical courses during the 2-year follow-up period.

RESULTS

Insight in consistently stable patients was steady during the 2-year period. Insight decreased during the manic period in patients with only a single manic episode as well as in those with repeated manic episodes. However, insight returned to the pre-episode level for patients with only a single manic episode, but did not for most of the patients with repeated episodes. No changes in insight were observed during depressive episodes for either patients with a single or those with repeated depressive episodes.

CONCLUSIONS

The types of insight changes among bipolar patients during the 2-year period were various and depended on the different clinical courses. Frequent mood disturbance episodes may cause patient insight to deteriorate.

Prefrontal cortex and insight in schizophrenia: a volumetric MRI study

Previous studies have suggested a relationship between frontal lobe-based neuropsychological functions and insight in schizophrenia. There is some evidence linking both smaller whole brain volume and frontal cortical atrophy to poor insight in this population. We investigated the relationship between total as well as specific prefrontal regional volumes and insight in schizophrenia. Twenty-eight stable outpatients with schizophrenia underwent magnetic resonance imaging scanning and assessment for insight. Insight was measured using the Birchwood self-report Insight Scale and the Expanded Schedule of Assessment of Insight. The whole brain and prefrontal regional (superior frontal, middle frontal, inferior frontal and orbitofrontal) volumes were then manually measured using the Cavalieri method and established criteria. Twenty healthy subjects were also scanned to provide control data for volumetric assessments. Smaller total prefrontal grey matter volume was moderately associated with a lower level of insight into the presence of illness. At the prefrontal sub-regional level, volumes of the superior, inferior and orbitofrontal regions contributed to this relationship, especially in males. It is concluded that smaller prefrontal grey matter volume is associated with poor insight into the presence of illness in stable schizophrenia patients. Future research should examine the association of specific dimensions of insight with frontal as well as non-frontal regional brain volumes.

Unawareness in schizophrenia: neuropsychological and neuroanatomical findings

The lack of insight in schizophrenia has so far been interpreted as a primary symptom of the illness, namely a defensive mechanism rather than a neurologically-based condition. However, recent findings have emphasized its relationship with damage to specific brain areas as well as the domain specificity in which it may occur. This supports a neuropsychological interpretation of the lack of insight in schizophrenia. The present article reviews the foregoing data, and takes into account the most relevant anatomo-clinical results. There is evidence that the lack of insight in schizophrenia may occur as a neurological disease per se following brain damage that seems related to frontal lobe areas. Additionally, it could either be related to all aspects of the disease or be domain-specific, occurring for one kind of symptom but not for others. These data indicate several analogies with the phenomenon called anosognosia for a neurological deficit.

Relationship between insight, cognitive function, social function and symptomatology in schizophrenia: the West London first episode study

OBJECTIVE

To examine the nature and clinical correlates of insight in first-episode schizophrenia, and how these differ from findings in established schizophrenia.

METHOD

Insight (and insight dimensions), clinical symptoms, neurocognitive function and social function were assessed in 94 patients with first-episode schizophrenia or schizophreniform disorder according to DSM-IV criteria.

RESULTS

Greater global insight was associated with more severe depression. Poor overall insight was associated significantly with more severe negative and disorganisation symptoms as well as poor working memory, and at a trend level with lower current IQ. Patients with poor insight perceived themselves to have a better level of independent performance at daily living activities.

CONCLUSION

In first-episode psychosis, the clinical correlates of poor insight are similar to those reported for established schizophrenia. Those patients with greater insight may be at risk of depression. The complex relationships between insight, positive and negative symptoms, neurocognitive dysfunction and social function may reflect the multidimensional nature of insight.

Insight and frontal cortical function in schizophrenia: a review

Insight into illness has been identified as a clinically important phenomenon, in no small part due to an association with treatment-adherence. An increasing number of studies, but not all, have observed poor insight to be a reflection of cognitive dysfunction in schizophrenia. A review of 34 published English-language studies found a significant number (i.e., 21) reporting a relationship between insight deficits and impaired performance on cognitive tasks primarily mediated by frontal cortex. A significant number of reviewed studies examined insight function in more than one psychiatric population, including bipolar and schizoaffective disorder. The most replicated findings from these studies were the correlations between insight deficits and impaired performance on the Wisconsin Card Sorting Test (WCST). More specifically, WCST perseverative errors correlated positively and the number of categories completed correlated negatively with poor insight, suggesting that impaired insight may be mediated by deficiencies in conceptual organization and flexibility in abstract thinking. Since the WCST requires the ability to demonstrate conceptual flexibility through the generation, maintenance and switching of mental sets along with the capacity to use verbal feedback to correct errors, it would appear that such 'executive' functions are most related to insight. In addition, recently identified structural correlates of poor insight in schizophrenia show some association with anosognosia in neurological patients. This review will discuss the implications of these findings and directions for future research.