Specific cognitive flexibility rehabilitation in schizophrenia

Parallel learning and cognitive flexibility impairments between Fmr1 knockout mice and individuals with fragile X syndrome

Introduction

Fragile X Syndrome (FXS) is a monogenic condition that leads to intellectual disability along with behavioral and learning difficulties. Among behavioral and learning difficulties, cognitive flexibility impairments are among the most commonly reported in FXS, which significantly impacts daily living. Despite the extensive use of the Fmr1 knockout (KO) mouse to understand molecular, synaptic and behavioral alterations related to FXS, there has been limited development of translational paradigms to understand cognitive flexibility that can be employed in both animal models and individuals with FXS to facilitate treatment development.

Methods

To begin addressing this limitation, a parallel set of studies were carried out that investigated probabilistic reversal learning along with other behavioral and cognitive tests in individuals with FXS and Fmr1 KO mice. Fifty-five adolescents and adults with FXS (67% male) and 34 age- and sex-matched typically developing controls (62% male) completed an initial probabilistic learning training task and a probabilistic reversal learning task.

Results

In males with FXS, both initial probabilistic learning and reversal learning deficits were found. However, in females with FXS, we only observed reversal learning deficits. Reversal learning deficits related to more severe psychiatric features in females with FXS, whereas increased sensitivity to negative feedback (lose:shift errors) unexpectedly appear to be adaptive in males with FXS. Male Fmr1 KO mice exhibited both an initial probabilistic learning and reversal learning deficit compared to that of wildtype (WT) mice. Female Fmr1 KO mice were selectively impaired on probabilistic reversal learning. In a prepotent response inhibition test, both male and female Fmr1 KO mice were impaired in learning to choose a non-preferred spatial location to receive a food reward compared to that of WT mice. Neither male nor female Fmr1 KO mice exhibited a change in anxiety compared to that of WT mice.

Discussion

Together, our findings demonstrate strikingly similar sex-dependent learning disturbances across individuals with FXS and Fmr1 KO mice. This suggests the promise of using analogous paradigms of cognitive flexibility across species that may speed treatment development to improve lives of individuals with FXS.

Cognitive Remediation Therapy Does Not Enhance Treatment Effect in Obsessive-Compulsive Disorder and Anorexia Nervosa: A Randomized Controlled Trial

BACKGROUND

Guideline-recommended therapies are moderately successful in the treatment of obsessive-compulsive disorder (OCD) and anorexia nervosa (AN), leaving room for improvement. Cognitive inflexibility, a common trait in both disorders, is likely to prevent patients from engaging in treatment and from fully benefiting from existing therapies. Cognitive remediation therapy (CRT) is a practical augmentation intervention aimed at ameliorating this impairing cognitive style prior to disorder-specific therapy.

OBJECTIVE

To compare the effectiveness of CRT and a control treatment that was not aimed at enhancing flexibility, named specialized attention therapy (SAT), as add-ons to treatment as usual (TAU).

METHODS

In a randomized controlled multicenter clinical trial, 71 adult patients with OCD and 61 with AN were randomized to ten twice-weekly sessions with either CRT or SAT, followed by TAU. Patients were evaluated at baseline, post-CRT/SAT, and after 6 and 12 months, with outcomes being quantified using the Yale-Brown Obsessive Compulsive Scale for OCD and the Eating Disorder Examination Questionnaire for AN.

RESULTS

Across study groups, most importantly CRT+TAU was not superior to control treatment (SAT)+TAU in reducing OCD and AN pathology. Contrary to expectations, SAT+TAU may have been more effective than CRT+TAU in patients being treated for OCD.

CONCLUSIONS

CRT did not enhance the effect of TAU for OCD and AN more than SAT. Unexpectedly, SAT, the control condition, may have had an augmentation effect on TAU in OCD patients. Although this latter finding may have been due to chance, the effect of SAT delivered as a pretreatment add-on intervention for adults with OCD and AN merits future efforts at replication.

What variables predict cognitive remediation associated improvement in individuals with psychosis?

On average, cognitive remediation (CR) is effective in improving cognitive function in individuals with psychosis, though there is considerable variability in treatment response. No consensus has emerged to date about the potential influence of patient and illness characteristics on CR efficacy. In the current analyses, we examined baseline demographic, cognitive, clinical, and functional ability variables as potential moderators of cognitive improvements during a randomized, controlled trial of a hybrid drill-and-practice plus strategy training CR intervention. In an attempt to disentangle non-specific vs. CR specific treatment effects, we separately examined potential predictors of cognitive improvement in individuals who received CR versus those in the control condition. Cognitive gains were predicted by a large array of demographic, symptom and cognitive variables, however this was true both in the CR and the control condition. CR-specific cognitive improvement was associated with more severe course of illness as indexed by higher number of hospitalizations, with poorer baseline cognition, and with less severe baseline negative symptoms.

[Tunisia: nursing practice of cognitive remediation in child psychiatry]

Cognitive remediation is today afforded a significant place in the treatment of neurodevelopmental disorders. A hospital team, comprising in particular a nurse offering consultations in a child psychiatry unit in a public hospital in Tunis, shares its experience with regard to this technique which aims to restore impaired cognitive functions in order to improve the efficiency and quality of life of young patients.

Autism spectrum disorder and schizophrenia: boundaries and uncertainties

Autism and schizophrenia were placed in different diagnostic categories in DSM-III, having previously been considered as related diagnostic entities. New evidence suggests that these disorders show clinical and cognitive deficit overlaps and shared neurobiological characteristics. Furthermore, children presenting with both autism spectrum disorder (ASD) and psychotic experiences may represent a subgroup of ASD more closely linked to psychosis. The study of ASD and childhood schizophrenia, and their clinical boundaries and overlapping pathophysiological characteristics, may clarify their relationship and lead to more effective interventions. This article discusses the relationship through a critical review of current and historical dilemmas surrounding the phenomenology and pathophysiology of these disorders. It provides a framework for working with children and young people with mixed clinical presentations, illustrated by three brief fictional case vignettes.

A dimensional approach to modeling symptoms of neuropsychiatric disorders in the marmoset monkey

Some patients suffering from the same neuropsychiatric disorder may have no overlapping symptoms whilst others may share symptoms common to other distinct disorders. Therefore, the Research Domain Criteria initiative recognises the need for better characterisation of the individual symptoms on which to focus symptom-based treatment strategies. Many of the disorders involve dysfunction within the prefrontal cortex (PFC) and so the marmoset, due to their highly developed PFC and small size, is an ideal species for studying the neurobiological basis of the behavioural dimensions that underlie these symptoms.Here we focus on a battery of tests that address dysfunction spanning the cognitive (cognitive inflexibility and working memory), negative valence (fear generalisation and negative bias) and positive valence (anhedonia) systems pertinent for understanding disorders such as ADHD, Schizophrenia, Anxiety, Depression and OCD. Parsing the separable prefrontal and striatal circuits and identifying the selective neurochemical modulation (serotonin vs dopamine) that underlie cognitive dysfunction have revealed counterparts in the clinical domain. Aspects of the negative valence system have been explored both at individual- (trait anxiety and genetic variation in serotonin transporter) and circuit-based levels enabling the understanding of generalisation processes, negative biases and differential responsiveness to SSRIs. Within the positive valence system, the combination of cardiovascular and behavioural measures provides a framework for understanding motivational, anticipatory and consummatory aspects of anhedonia and their neurobiological mechanisms. Together, the direct comparison of experimental findings in marmosets with clinical studies is proving an excellent translational model to address the behavioural dimensions and neurobiology of neuropsychiatric symptoms. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 328-353, 2017.

Cognitive and psychological flexibility after a traumatic brain injury and the implications for treatment in acceptance-based therapies: A conceptual review

This paper provides a selective review of cognitive and psychological flexibility in the context of treatment for psychological distress after traumatic brain injury, with a focus on acceptance-based therapies. Cognitive flexibility is a component of executive function that is referred to mostly in the context of neuropsychological research and practice. Psychological flexibility, from a clinical psychology perspective, is linked to health and well-being and is an identified treatment outcome for therapies such as acceptance and commitment therapy (ACT). There are a number of overlaps between the constructs. They both manifest in the ability to change behaviour (either a thought or an action) in response to environmental change, with similarities in neural substrate and mental processes. Impairments in both show a strong association with psychopathology. People with a traumatic brain injury (TBI) often suffer impairments in their cognitive flexibility as a result of damage to areas controlling executive processes but have a positive response to therapies that promote psychological flexibility. Overall, psychological flexibility appears a more overarching construct and cognitive flexibility may be a subcomponent of it but not necessarily a pre-requisite. Further research into therapies which claim to improve psychological flexibility, such as ACT, needs to be undertaken in TBI populations in order to clarify its utility in this group.

Traumatic Brain Injury and Psychosocial Function: Let's Get Social

Disorders of psychosocial function manifested in a reduction in socially skilled behaviour, are prevalent following traumatic brain injury. It is clear to most clinicians that these can present the major obstacle to successful rehabilitation. Outcome studies also support this view. Despite this, there is relatively little systematic work addressing social skills remediation in Australia or elsewhere. There are even fewer studies that have evaluated the effectiveness of social skills treatment after traumatic brain injury. In this address I will consider social skills from a social skills framework that has been developed in the normal literature. This framework encompasses social behaviour and social perception (i.e., the ability to read cues accurately and social problem-solving). Social behaviour is the most common target for remediation in both the normal and brain-injured populations. There is a range of useful techniques that have proven to be efficacious in treating social skills in non-brain-injured populations and also to have some effectiveness in the treatment of traumatic brain injury. In addition, however, it is clear that both social perception (i.e., the ability to read social cues accurately and social problem-solving are also compromised after TBI). These areas are infrequently targeted for remediation, although again, there are some remediation principles that are relevant and potentially fruitful. Finally, it is important to understand the impact of psychological reactive factors such as depression and poor self-esteem in producing or maintaining poor social skills.

Cognitive remediation in schizophrenia

Cognitive deficits are routinely evident in schizophrenia, and are of sufficient magnitude to influence functional outcomes in work, social functioning and illness management. Cognitive remediation is an evidenced-based non-pharmacological treatment for the neurocognitive deficits seen in schizophrenia. Narrowly defined, cognitive remediation is a set of cognitive drills or compensatory interventions designed to enhance cognitive functioning, but from the vantage of the psychiatric rehabilitation field, cognitive remediation is a therapy which engages the patient in learning activities that enhance the neurocognitive skills relevant to their chosen recovery goals. Cognitive remediation programs vary in the extent to which they reflect these narrow or broader perspectives but six meta-analytic studies report moderate range effect sizes on cognitive test performance, and daily functioning. Reciprocal interactions between baseline ability level, the type of instructional techniques used, and motivation provide some explanatory power for the heterogeneity in patient response to cognitive remediation.

Cognitive rehabilitation for schizophrenia and the putative role of motivation and expectancies

Cognitive rehabilitation (CR) approaches seek to enhance cognitive processes or to circumvent cognitive impairments in schizophrenia in an effort to improve functional outcome. In this review we examine the research findings on the 8 evidence-based approaches to cognitive remediation listed in the 2005 Training Grid Outlining Best Practices for Recovery and Improved Outcomes for People With Serious Mental Illness, developed by the American Psychological Association Committee for the Advancement of Professional Practice. Though the approaches vary widely in theoretical orientation and methods of intervention, the results are, for the most part, encouraging. Improvements in attention, memory, and executive functioning have been reported. However, many persons with schizophrenia are more impaired in real-world functioning than one would expect given the magnitude of their cognitive deficits. We may need to look beyond cognition to other targets such as motivation to identify the reasons that many persons with schizophrenia demonstrate such marked levels of disability. Although a number of current CR approaches address motivation to varying degrees, treating motivation as a primary target may be needed to maximize CR outcomes.

Cognitive training of verbal memory using a dichotic listening paradigm: impact on symptoms and cognition

OBJECTIVE

The objective was to investigate the impact of a verbal memory training task on psychiatric symptoms and cognition in schizophrenia.

METHOD

As part of a larger, 6-month cognitive remediation program, 57 patients with schizophrenia were randomly assigned to receive performance-based, hierarchical training on a verbal memory task based on a dichotic listening (DL) with distracter paradigm. These patients were compared with 68 patients who had been randomly assigned to a control condition.

RESULTS

Training on the DL task was not associated with changes in general psychopathology or auditory hallucinations (AH) specifically. Training was associated with improvements in verbal memory, but not attention.

CONCLUSION

The current investigation adds to the growing literature on the effectiveness of cognitive remediation training and indicates that training on the DL task enhances verbal episodic memory. The results do not support the use of DL training as a method for reducing AH.

Treatment of cognitive dysfunction in psychiatric disorders

Most people with severe and persistent psychiatric disorders have significant cognitive deficits. Both schizophrenia and affective disorders with psychosis are associated with problems in attention, memory, and executive functioning. These deficits are predictive of lower work status, impairments in social skills, and poorer response to psychosocial skills training. Cognitive impairment makes it difficult for individuals to benefit from focused skills interventions that they are offered. This article describes behavioral treatments available to address cognitive dysfunction in individuals with psychiatric disorders. The evidence for efficacy is reviewed and recommendations are made for ways to begin addressing cognitive impairment in mainstream psychiatric practice.

Wisconsin Card Sorting Test performance in schizophrenia: the role of working memory

Schizophrenia typically results in reduced performance on the Wisconsin Card Sorting Test (WCST). In the current study, we used a variety of approaches to examine the role of working memory (WM) in this deficit. One approach was to examine patterns of perseverative and non-perseverative errors. A second approach involved the comparison of the standard WCST to a modified version that used visual cues to reduce demands on WM. A third approach was to quantify the impact of WM demands on performance on a trial by trial basis. Consistent with theories of WM, the schizophrenia group showed increases in both perseverative and non-perseverative errors and differences between individuals with schizophrenia and controls were largest when WM demands were high. The visual cues helped the schizophrenia group overcome the high WM demands of the test, although they did not reduce the impairment in terms of standard scoring procedures. All impairments disappeared, however, after controlling for group differences on a measure of the speed of encoding information in WM. The pattern of results supports the conclusion that WM impairment contributes to poor performance on the WCST in individuals with schizophrenia, with additional evidence that this impairment results from generalized slowing of information processing.

The impact of cognitive remediation on psychiatric symptoms of schizophrenia

OBJECTIVE

The relationship between psychopathology and cognitive functioning in schizophrenia is of interest, both for an understanding of the nature of the disease, and for comprehensive treatment planning. The aim of this study was to investigate how psychiatric symptoms affect, and are affected by, cognitive remediation.

METHOD

Fifty-four psychiatric inpatients received either cognitive remediation exercises (remediation group) or no cognitive intervention (control group). The subjects' scores on tests of cognition and on the Positive and Negative Symptoms Scale (PANSS) were measured before, after the 10 session treatment, and again 4 weeks post treatment.

RESULTS

Only the remediation group showed significant and persistent improvement on all three PANSS Subscales as well as on the Positive Symptoms and Depression Factors. There were no significant between-group differences on any PANSS pre/posttreatment change scores. Baseline measures of psychopathology did not correlate meaningfully with amount of change made on cognitive measures after rehabilitation.

CONCLUSIONS

A brief 10-session course of cognitive remediation is sufficient to benefit cognition and has some positive effects on psychopathology as measured by the PANSS, but does not add significantly to the effects of standard psychiatric treatment on psychopathology. Furthermore, psychiatric symptom profile is not predictive of the degree to which cognitive symptoms respond to cognitive remediation. The differential impact of cognitive remediation on cognition and psychopathology may imply that psychopathology and cognitive functioning follow fairly independent treatment courses.

Cognitive rehabilitation in schizophrenia: a quantitative analysis of controlled studies

RATIONALE

Cognitive rehabilitation is now recognized as an important tool in the treatment of schizophrenia, and findings in this area are emerging rapidly. There is a need for a systematic review of the effects of the different training programs.

OBJECTIVES

To review quantitatively the controlled studies on cognitive rehabilitation in schizophrenia for the effect of training on performance on tasks other than those practiced in the training procedure.

METHODS

A meta-analysis was conducted on 12 controlled studies of cognitive rehabilitation in schizophrenia taking into account the effects of type of rehabilitation approach (rehearsal or strategy learning) and duration of training.

RESULTS

The mean weighted effect size was 0.45, with a 95% confidence interval from 0.26 to 0.64. Effect sizes differed slightly, depending on rehabilitation approach, in favor of strategy learning, but this difference did not reach statistical significance. Duration of training did not influence effect size.

CONCLUSIONS

Cognitive rehabilitation can improve task performance in patients with schizophrenia and this effect is apparent on tasks outside those practiced during the training procedure. Future studies should include more real-world outcomes and perform longitudinal evaluations.

Everyday memory and laboratory memory tests: general function predictors in schizophrenia and remitted depression

This study was designed to compare neuropsychological memory measures ("laboratory memory tests") and an everyday memory measure in patients with schizophrenia, patients with major depression, and normal controls. Patients with schizophrenia ( N= 68) treated with typical (N = 33) or atypical ( N= 35) neuroleptics, patients with major depression (N = 30), and a control group (N = 36) were evaluated with clinical measures (Positive and Negative Syndrome Scale and Hamilton Depression Rating Scale), laboratory memory tests (Digit-Span, Paired-Associates, Rey Complex Figure Test, and Digit-Symbol), everyday memory test (RMBT), and the Global Assessment of Functioning (GAF). The schizophrenia group had a significantly lower level of performance in everyday memory and general function but not in laboratory memory tests. Verbal and everyday memory measures were correlated with general function. The diagnosis rather than current symptoms (in remission) contributed to test variance and was correlated with performance on everyday memory and general function tests. Everyday memory and verbal memory were good predictors of general function in schizophrenic and depressive patients in the remitted phase. However, the advantages of these tests over laboratory memory tests need to be further investigated in larger and more representative samples.

Could the hypofrontality pattern in schizophrenia be modified through neuropsychological rehabilitation?

OBJECTIVE

The effects of neuropsychological treatment on cognitive hypofrontality were examined in schizophrenic patients through the score activation.

METHOD

Eight subjects (six men and two women) with persistent negative symptoms and cognitive impairments were evaluated with single photon emission computed tomography (SPECT) procedures and neuropsychological battery before and after a neuropsychological treatment group.

RESULTS

After treatment an enhancement in neuropsychological performance was found, especially in executive functions. The activation score showed an increase over baseline levels and no cognitive-dependent hypofrontality after treatment was found. Although the prefrontal blood flow changes were small and non-specific, they suggest a reduction of the cognitive hypofrontality after neuropsychological treatment.

CONCLUSION

Cognitive improvements after neuropsychological treatment would possibly be related with the diminution of the functional hypoactivity in the prefrontal areas.

Is it time to develop a new cognitive therapy for psychosis--cognitive remediation therapy (CRT)?

The cognitive difficulties associated with the disorder of schizophrenia seem to be predictive of future dependence on psychiatric services and predict social functioning. Cognitive remediation therapy (CRT) was designed to rehabilitate these cognitive functions, and the interest in it has grown dramatically over the past ten years. However, the programmes are rarely based on clear theoretical principles and sometimes rely heavily on practice rather than guided learning. The evidence for their efficacy is variable and seems to be dependent on the use of specific components of training. The current review tries to put this evidence into context and sets out a programme of research, which is essential in this area if future progress is to be made.

Evaluation eines kognitiven Strategietrainings in der ambulanten beruflichen Rehabilitation Schizophrener

Zusammenfassung. Theoretischer Hintergrund: Kognitive Funktionsstörungen bei schizophrenen Erkrankungen bedeuten ein erhöhtes Risiko für soziale und berufliche Integration sowie ein reduziertes Ansprechen auf psychosoziale Interventionsmaßnahmen. Fragestellung: Wirksamkeit eines computerunterstützten kognitiven Strategietrainings in der Gruppe zur Verbesserung von Aufmerksamkeit, verbaler Merkfähigkeit und exekutiven Funktionen im Vergleich zu einer Kontrollgruppe i.R. ambulanter Arbeitsrehabilitation (Arbeitstraining). Methode: Stratifizierte (konventionelle vs. atypische neuroleptische Medikation) Randomisierung von 59 schizophrenen Patienten mit der DSM-IV-Diagnose einer Schizophrenie zu kognitivem Strategietraining bzw. Kontrollgruppe. Ergebnisse: Es zeigten sich gegenüber der Kontrollgruppe Leistungssteigerungen i.B. der selektiven Aufmerksamkeit, der verzögerten Reproduktion, der Lernfähigkeit und des Arbeitsgedächtnisses. Schlußfolgerungen: Insbesondere die Verbesserung der Lernfähigkeit kann als wichtiger Beitrag zur Ausweitung des Rehabilitationspotentials schizophren Erkrankter gesehen werden. Offen bleibt der spezifische Beitrag eines strategieorientierten gegenüber einem auf Automatisation kognitiver Teilfunktionen gerichteten therapeutischen Vorgehen, insbesondere im Hinblick auf eine Generalisierung der Effekte auf Verbesserung sozialer und beruflicher Rollenfunktionsfähigkeit.

Treating problem-solving deficits on an acute care psychiatric inpatient unit

Neuropsychological deficits in problem-solving are commonly found in patients with schizophrenia and severe affective disorders. However, in an acute care setting, treatment efforts do not typically target these deficits, even though they can impede recovery. This study aimed to evaluate the effectiveness of short-term problem-solving remediation in acutely ill psychiatric inpatients. Twenty-eight psychiatric inpatients identified as having a verbal problem-solving deficit received 6 h of either verbal problem-solving remediation or placebo instruction. Before and after treatment a nurse rated the patient's psychiatric status and the patient completed verbal and nonverbal problem-solving tests, and a self-report rating of symptoms and ability to cope with symptoms. Both groups of patients improved on the measure of verbal problem solving, but those receiving problem-solving remediation improved significantly more. Both groups made symptomatic improvement, but the patients receiving problem-solving remediation made significantly more improvement on the measure of coping ability and the nurses rated them as more improved, both psychiatrically and with regard to coping skills. Verbal problem-solving deficits are responsive to short-term remediation in an acute care setting, and treatment effects may generalize to improve ability to cope with psychiatric symptoms.

Cognitive rehabilitation for people with schizophrenia and related conditions

BACKGROUND

Researchers have consistently found that people with schizophrenia score more poorly than others on a wide array of cognitive tasks and that these deficits persist even when the illness is in remission. The perceived impact of cognitive impairment on day-to-day functioning has led to the development of cognitive rehabilitation techniques intended to remedy these impairments, and thus improve the functioning of people with schizophrenia.

OBJECTIVES

To determine whether the use of cognitive rehabilitation techniques is associated with improvement in people with schizophrenia and related conditions.

SEARCH STRATEGY

Electronic searches of Biological Abstracts (1982-1997), the Cochrane Schizophrenia Group's Register of trials (2000), EMBASE (1980-1997), LILACS (1982-1997), MEDLINE (1966-1997), PsycLIT (1974-1997) and SCISEARCH (1997) were undertaken. References of all identified studies were handsearched and the first author of each included trial was contacted.

SELECTION CRITERIA

The reviewers included randomised trials investigating the impact of cognitive rehabilitation on people with schizophrenia, or related conditions, compared to a placebo intervention, another intervention or standard treatment. This version of the review does not include comparisons of different types of cognitive rehabilitation.

DATA COLLECTION AND ANALYSIS

Relevant studies were identified and data extracted reliably by two reviewers working independently. In studies which did not specify the reasons for participants dropping out, we assumed that those who had dropped out had experienced no change in the outcome measures. Where possible, Peto odds ratios (OR) and mean differences (MD) were calculated with their 95% confidence intervals (CI).

MAIN RESULTS

Three small studies met the inclusion criteria. Two compared cognitive rehabilitation to a placebo intervention (total n=84), and the other to occupational therapy (n=33). Although cognitive rehabilitation was as acceptable as placebo and occupational therapy, with low attrition in both groups, no effects were demonstrated on measures of mental state, social behaviour, or cognitive functioning. An effect, in favour of cognitive rehabilitation, on a measure of self-esteem (Rosenberg Self-Esteem Scale, MD 6.3 CI 1.07-11.53 ) is worthy of replication in any future trials.

REVIEWER'S CONCLUSIONS

Data are inconclusive and provide no evidence for or against cognitive rehabilitation as a treatment for schizophrenia.

Cognitive deficits and cognitive training in schizophrenic patients: a review

OBJECTIVE

The aim of this paper is to review the current status of knowledge of cognitive deficits and remediation in patients with schizophrenia.

METHOD

Relevant reports were identified by a literature survey. In addition, some outstanding researchers in these areas were asked to add to the identified list relevant literature that was not included.

RESULTS

Our review focuses on the cognitive deficits observed in the areas of attention, memory and executive functions. We attempt to classify dysfunctions as vulnerability- or symptom-linked factors, and we discuss the methodological question of a general performance deficit vs. a differential deficit. Furthermore, we briefly delineate how antipsychotics affect cognitive functions. Finally, controlled studies of cognitive training are discussed in more detail.

CONCLUSION

The most outstanding cognitive dysfunctions in patients with schizophrenia can be related to the areas of attention, memory and executive functions. Interest in cognitive remediation has to some extent been rekindled in the 1990s. However, few studies on the effects of cognitive training programs have been conducted.

Comparison of set-shifting ability in patients with chronic schizophrenia and frontal lobe damage

Neuropsychological studies of patients with schizophrenia have consistently identified deficits on tests sensitive to frontal lobe function. One paradigm that has been widely used is that of attentional set-shifting using the Wisconsin Card Sorting Test (WCST). In the present study, patients with chronic schizophrenia and with frontal lobe lesions were assessed on a computerised set-shifting task that provides a componential analysis of the WCST by distinguishing between intra-dimensional and extra-dimensional set-shifting. Out of 51 patients with schizophrenia, those with high IQ (n =24) were compared with patients with lesions in prefrontal cortex (n = 22) and with normal control subjects (n= 18). These three groups were well matched for age, sex and National Adult Reading Test (NART) IQ. The schizophrenic group showed a significantly higher rate of attrition at the intra-dimensional shift stage of learning compared with the other two groups. At the extra-dimensional shift stage, both the schizophrenic and frontal lesioned groups showed greater attrition than controls. Further, patients with schizophrenia who were able to learn the intradimensional reversal stage required more trials and made significantly more errors at that stage than the other two groups. In comparison with high IQ patients with schizophrenia, those with low IQ performed at a lower level but showed a qualitatively similar pattern of performance, providing further evidence that the set-shifting deficits were not simply explained by any global intellectual decline. Patients with schizophrenia who dropped out at the extradimensional shift stage had higher negative symptom scores compared with patients dropping out at previous learning stages, while patients failing at the intra-dimensional shift stage had lower scores for bradyphrenia (slowness of thought). The results suggest that patients with chronic schizophrenia fail to 'learn set' and are impaired at both set-shifting and concept formation. The relevance of these findings to understanding the nature of prefrontal cortical deficits in chronic schizophrenia is discussed. The implication of these findings to the rehabilitation of these patients is considered.

What are we changing with neurocognitive rehabilitation? Illustrations from two single cases of changes in neuropsychological performance and brain systems as measured by SPECT

If cognitive remediation is to be developed further, there have to be not only large-scale randomized trials but also detailed analysis of the strategies used to produce improved performance. In this study the strategies adopted by two people who took part in a remediation program are investigated, with their results on neuropsychological tasks and with concomitant brain image data gathered via SPECT while the participant was performing a Verbal Fluency task. After remediation there were improvements in many of the neuropsychological tests, and changes in the scan data. The changes in strategies and brain activation were different for both individuals. One person increased his verbal output but without close monitoring, so also increased his errors. The other participant decreased his output but monitored it more closely, and so decreased the errors. These strategies were reflected in the changes in activation between scans, i.e. increases in temporal areas for the increased output and bilateral decreases in the anterior cingulate and left pre-motor areas for the decreased output case. Together these results imply that the participants continue to use individual strategies which for many of the neuropsychological tasks produced gains. Further investigation of whether it is possible to change idiosyncratic strategy use is needed if we are to develop the efficacy of this remediation technique.

The varied outcomes of schizophrenia

OBJECTIVE

To review variations in outcomes in schizophrenia across individual, historical, and cross-cultural boundaries, as well as within specific domains of functioning.

METHOD

Research literature on the outcomes of schizophrenia appearing within the last 8 years was reviewed.

RESULTS

First, a review of follow-up studies published in the developed world suggests that heterogeneity in outcome across individuals with schizophrenia remains the rule, with affective symptoms, later and acute onset, and responsiveness to biological treatments predictive of good outcome. Negative symptoms are associated with poor outcome, cognitive impairments, and incapacity in social and work domains. Deterioration appears to occur within the first few months of onset if not already in the prodrome, with recent early-course studies finding longer duration of untreated psychosis associated with insidious onset, negative symptoms, social and work incapacity, and poor outcome. Second, a review of recent cross-cultural and historical studies provides evidence that outcome varies across time and place, schizophrenia having a more favourable outcome in the developing world and becoming a more benign disorder over the course of this century. Third, a review of studies of the domains of functioning within individuals identifies 4 relatively independent dimensions of depression and negative, psychotic, and disorganized symptoms. Cognitive deficits, which are associated with negative symptoms, also constitute a relatively stable dimension over time, showing neither marked deterioration nor improvement once established early in the course of disorder.

CONCLUSIONS

The early appearance and stability over time of negative symptoms and cognitive impairments call for assertive intervention efforts early in the course of disorder to prevent chronicity and prolonged disability.

Rehabilitation of frontal/executive impairments in schizophrenia

OBJECTIVE

A relatively high prevalence of deficits in cognitive flexibility, working memory and planning ability has been reported in schizophrenia patients. The objective was to develop a rehabilitation training program in an attempt to improve these specific cognitive functions.

METHODS

The deficits in cognitive flexibility, working memory and planning ability were interpreted as reflecting executive cognitive processing impairments secondary to prefrontal neural system dysfunction. Following the 'process specific' approach, it was considered important to develop tasks that hypothesised the exercise of these cognitive abilities and the more molecular information processes thought to be fundamental to these abilities. Care was taken to ensure that all tasks involved the practice of processes thought to activate frontal/prefrontal neural systems. Attentional, visual, verbal, conceptual, motor and fine motor tasks were considered important for each process area in order to involve as many functional modalities as possible.

RESULTS

A program comprising cognitive shift, working memory and planning modules was developed. Conducted over 11 weeks, four modules were of 2 weeks' duration, and the fifth of 3 weeks' duration. Four individual 1 hour training sessions were conducted each week. Core elements of the modules are described.

CONCLUSION

Consisting predominantly of pencil and paper information processing exercises, all of the training exercises are presented in the volumes of the Frontal/Executive Program. The program appears to be user-friendly with therapists now successfully delivering the program, in its entirety, to schizophrenia patients. Should future studies replicate preliminary findings of improved neurocognitive performance following training with the program, such findings would have important implications for the treatment of schizophrenia.

Cognitive therapy with schizophrenic patients: conceptual basis, present state, future directions

Schizophrenia may nowadays be most readily understood as a systemic disorder in which changes in the brain structure underlie individual cognitive abnormalities which for their part interact with environmental factors at the onset of the illness and during its course. From this, one may deduce the rationale for cognitive therapy for schizophrenic patients. Existing approaches may be systemised as direct, indirect and combined procedures. The latter are based on the assumption of the pervasive effects of elementary and complex cognitive dysfunctions at the levels of open behaviour. However, in a mirror-design study with 21 schizophrenic patients according to DSM-III-R in which the effects of various intervention sequences were examined, it was not possible to find confirmation for this. This and other open questions have led to doubts expressed in current literature concerning the utility of cognitive therapy, especially with respect to the locus, nature and malleability of cognitive disorders, as well as the possibility of generalizing cognitive improvements. The latter are discussed in detail and possible future directions in cognitive therapy for schizophrenic patients are shown.

Predicting symptomatic and behavioural outcomes of community care

BACKGROUND

Many studies of community care show little overall improvement in patient functioning. This study investigated whether cognitive impairment mediates the effect of the increased opportunities offered by the community.

METHOD

Behaviour, symptoms, sociodemographic variables and information processing of a random sample of chronic psychiatric patients were examined. Six years later, social and behavioural outcomes were measured.

RESULTS

The overall change in the group was negligible. Individual variation can be accounted for by two factors: time since transfer to the community, and initial information processing problems. Patients transferred for at least three years showed significant improvements. Schizophrenic patients without information processing problems improved, but those with deficits got worse.

CONCLUSIONS

The identification of mediating factors should allow better rehabilitation plans, and alleviate the toxic effects that transfer has on some patients' functioning.