Cognitive Remediation Therapy for Schizophrenia

Theory and Practice

Professor Til Wykes, Dr Clare Reeder

• Publisher: Routledge
• Year: 2006
• Print ISBN: 9781583919712
• eBook ISBN: 9781135444099
• Topic: Psychology
• Subtopic: Clinical Psychology
• Index: Psychology

Could CRT provide the first structured method of alleviating cognitive deficits associated with schizophrenia?

Cognitive Remediation Therapy for Schizophrenia describes the background and development of this new psychological therapy and demonstrates how it provides the first structured help to overcome the thinking problems associated with schizophrenia.

In three sections, the book covers the theoretical and empirical underpinning of cognitive remediation therapy and explores its application. Part I, 'The Development of Therapy', provides the historical context and theoretical background to the therapy and emphasizes the value of rehabilitating cognitive deficits. In Part II, 'Improving Cognitive Processes', the process and effects of changing cognition are examined. Finally, in Part III, 'The Process of Therapy', the authors provide a clinical guide to the delivery of cognitive remediation therapy and use case examples to support its efficacy.

This book is the first to describe an individual cognitive remediation therapy programme based on a clear model of the relationship between thinking and behaviour. It will be of both academic and clinical value to all those health professionals and clinical academics who want not only to understand the relationships between thought and action but also to intervene to improve therapy.

Part I
The development of therapy

Chapter 1

The historical context of cognitive remediation therapy (CRT) for schizophrenia

Cognitive problems are the most obvious sign of a diagnosis of schizophrenia, but for a considerable time following the genesis of the diagnosis little attention was paid to the alleviation of these problems. The prime targets for treatments were the positive symptoms and cognitive difficulties were considered to be reduced by medication. It is only recently that both the pharmacological and psychological research communities have identified improving thinking skills as an important target. This is, in part, because several studies have now suggested that cognitive problems rather than symptoms are associated with later functional outcome.

As treatment moved from relatively supportive institutions to care within the community, the effects of functional disabilities became more prominent, particularly as these disabilities were chronic. This encouraged health services to focus attention on rehabilitation potential, which was not, of course, a new focus, but a renaissance of ideas from the eighteenth century. There have been a number of research drivers resulting from this change of focus. Increased social inclusion for people with mental health problems has now become a policy issue for mental health services all over the globe, fuelling research into the technology for achieving this goal. In order to justify expenditure on rehabilitation programmes, outcome data for an evidence base, particularly randomised control trials, are needed. This in turn illuminates the lack of clear theoretical underpinnings for these programmes.

Investigations into functional outcome have highlighted the role of cognition not only in concurrent functioning but also in the prediction of future outcome and this led to the recent concentration of efforts to enhance cognition. Two primary strategies have been adopted to provide (a) pharmacotherapy and (b) psychological therapy. For the first – medication – the effectiveness was initially seen as solely for hallucinations and delusions, but lately the additional effects of these same medications on cognition have been investigated. As yet, no specific pharmacological intervention has been advocated exclusively for the cognitive problems, but this is clearly an important avenue for future research. This process of the development of cognition-specific medication has been hindered in part by controversies over trial design and how to assess whether medication has an effect on cognition. These are currently under investigation in the MATRICS project in the USA (www.matrics.ucla.edu).

Recent advances in psychological interventions have produced a new rehabilitation technology which we will call Cognitive Remediation Therapy (CRT). The theory behind this technology is based on broad empirical find-ings concerning the relationships between cognition and functioning and is supported by some clinical outcome data. CRT is an umbrella expression under which there are a number of different sorts of intervention. These are mainly defined by their surface characteristics, such as use of a therapist and the types of training task used. It is harder to differentiate them on the basis of their theoretical model, as few describe one. Models that do appear tend to describe the relationships between cognition and performance (Brenner et al. , 1994; McGurk and Mueser, 2003) but do not indicate what the technology for changing the relationship would look like. The modelling process and the rehabilitation approaches have been influenced by approaches to the rehabilitation of traumatic brain injury. For instance, the Spaulding et al. (2003) model of cognitive recovery is a relatively bottom-up model with basic cognitive functions being the prime target. This is akin to some of the models of brain plasticity. This is one of the few models that could drive the technology for rehabilitation.

The aim of this book is to describe the current context for CRT, to introduce our own model that we believe can aid the future development of more effective CRT therapies and finally to describe one way of implementing the model into treatment. The model is based not only on changing specific cognitive processes but is predicated on the importance of metacognition. Metacognition here refers to the ability to reflect on your own cognitive abilities and adjust cognitive processing accordingly. So when people are aware of memory difficulties they can make adjustments, for example, use a cueing system in their diary to remind them, or try to encode information more deeply so that they are more likely to retrieve it. The main emphasis in our model is on changes in performance based not only on the development of new schemas to guide thinking behaviours such as rehearsing to-beremembered information, but also the use of such schemas in new situations, i.e. a transfer of training. This transfer is vital if these cognitive interventions are to have a more widespread effect on behaviour than merely increasing the scores on neuropsychological tests.

Cognitive remediation is a therapy which was subject to little investigation until the 1990s, and even then it was introduced to support the hypothesis that it is impossible to teach certain cognitive operations to people with schizophrenia. The research zeitgeist at that time was that cognitive problems were a trait factor in schizophrenia related to biological changes which could not be reversed. While not yet arguing for recovery using this sort of therapy, it seems to us that undoubted improvements can be made in thinking skills with treatment. Although some have argued that simply finding improvements in thinking should be the sole outcome measure of such a rehabilitation technology, we are of the view that interventions should attempt to have an impact on functioning, particularly that which relates to social inclusion, such as employment.

All new therapies need to be justified from a theoretical and practical standpoint. This book will present evidence on the criteria for successful therapy with practical examples to aid the introduction of therapy into services. But, in addition to scientific criteria on which to judge the efficacy and effectiveness of therapy, we must also consider a new set of criteria – those fixed by consumers. Both the therapeutic target and the measurement of outcomes need their endorsement. If consumers are not included at an early stage then the likelihood of therapy being translated into practice in mental health services is seriously in jeopardy. These consumer views have also been given a high priority in guiding the development of our form of cognitive remediation therapy.

This book is designed to provide an introduction to psychologists, nurses, psychiatrists, social workers and occupational therapists to this new form of cognitive therapy, but it will also provide a guide to researchers on issues that need to be further investigated to stimulate therapy development.

Should we use syndromes, symptoms or diagnosis?

In order to design a therapy we need to define who we are talking about, and in the field of schizophrenia there are several different views of who should be included. For instance, we could take a broad view and design a therapy for anyone who experiences a single symptom of the disorder, or we could con-fine our therapy for those who have a specific set of characteristics (termed syndromes or diagnoses). This is an important question because it will affect not only which studies we should use as evidence but also the final scope of a health service to provide such therapy.

If we consider using the loosest definition, we must turn to epidemiological data from which it is possible to estimate how many people experience some of the symptoms of schizophrenia at some time during their life. The lifetime estimates of the occurrence of hallucinations in the community lie between 10 and 39 per cent (Johns and van Os, 2001). Although it is clear that there are different rates between different cultural groups (Johns et al., 2002), we also know that the majority of people who experience individual symptoms lead ordinary lives and do not come into contact with the psychiatric services.

Psychological researchers have often advocated the investigation of these individual symptoms rather than collections of symptoms (syndromes) or diagnostic categories because they do exist outside diagnostic categories and there is also an overlap of symptoms between different diagnostic groups (e.g. Bentall, 2003). But although agreeing with the principle of this research paradigm, it is clear that a diagnosis of schizophrenia not only picks out those people from the community whose symptoms are distressing, but there is also evidence that it confers a higher likelihood of reductions in functioning over a lifetime (van Os et al., 1997). If cognitive technologies are to have the maximum impact, we feel that they should concentrate on the most disabled group of people. The majority of data on general treatment and outcome as well as cognition also relate to diagnoses. We have therefore chosen to concentrate on a categorical diagnosis of schizophrenia throughout this book. However, we will also make reference to the relationship of cognition to individual symptoms and will discuss the direct and indirect effects of CRT on these symptoms in the context of a diagnosis of schizophrenia.

The course of schizophrenia

Schizophrenia affects around 1 per cent of the population. For many of these people the effects of the abnormal perceptions and changes in beliefs are not only distressing but are also disabling. The symptoms can be episodic and disappear between episodes and some people with the diagnosis undoubtedly making a good recovery from the disorder. Follow-up studies suggest that between 27 per cent and 46 per cent never have a subsequent episode or show a good recovery between episodes (Ciompi, 1980; Shepherd et al., 1989). However, since the changes in the diagnostic criteria with many countries adopting those published in the fourth edition of the American Psychiatric Association’s Diagnostic and Statistical Manual, the probable outcomes of people with the disorder have been reduced, as briefer psychotic reactions which are associated with better outcomes are excluded. DSMIV includes criteria for the persistence of symptoms and reduction in social or work functioning of at least six months. Some argue that this has led to more pessimistic views of the outcome of the disorder.

There are different forms of a more chronic course where social functioning is reduced and interspersed with unremitting, acute or residual symptoms. These forms are estimated to occur in about 24 per cent of people with the diagnosis (Salokangas, 1983). It is this group of people who have a need for rehabilitation and support that have been the target for cognitive remediation. However, poor levels of functioning mean that a large number of people with schizophrenia need help with their living conditions in the form of specific residential care, or supportive housing and so may also find CRT beneficial. Few people are financially independent. Although estimates vary with the economic climate, and particularly the background rate of unemployment, the proportion of people with jobs who have a psychiatric diagnosis is always much lower than in the general population. The rate of employment rarely gets above 10 per cent and people with severe mental illnesses, when working, work fewer hours and generally earn less than the national average hourly wage (Cook and Razzano, 2000; Huxley and Thornicroft, 2003). In addition, the rate of marriage or stable partnerships is lower than the general population and people with schizophrenia also report fewer close friends and supportive relationships outside the psychiatric services (Becker et al., 1998)

Mapping the problem

What are the key factors to be considered if the aim is to improve cognition and its impact on the quality of life of people with schizophrenia? The first issue to map out is the actual extent of the outcome problems. Clearly, if the outcomes are uniformly poor, with little change over the lifespan, then any therapy probably needs a considerable effect size to have any consequences for functioning. The outcome data do appear pessimistic with a cursory look and this view is generally taught in psychiatric texts and was accepted in the psychiatric care community for many years. Schizophrenia was viewed as a disorder that showed a decline in functioning, particularly over the early years. But there are now data to suggest that even when the disorder is chronic, there is still room for change. For instance, Harding and colleagues have shown that good outcomes can be achieved with positive changes in aspects of functioning taking place at different times in the life course, even in a chronically disabled sample (Harding et al., 1987a, 1987b). This had led to some optimism about overall outcome and more enthusiasm for recovery models and the results of rehabilitation programmes.

One could argue that if it is functioning that is to be improved then there should be a concentration on efforts to change this directly and this has been the approach to improving life skills in the past. However, it is now clear that there are a number of different factors that impede skills learning. These include cognitive difficulties which are apparent in a proportion of people with schizophrenia. As well as cognitive intervention programmes affecting cognition, they could also have a knock-on or a boosting effect on the results of life skills programmes. We will also argue that a comprehensive approach in which cognitive difficulties are taken into account in the design of the life skills programmes is the most adaptive way forward.

The model of schizophrenia that is most widely accepted is the biopsychosocial model which consists of interactions between social, biological and psychological factors. These factors may be either the vulnerability or protective factors and affect the onset, recovery and subsequent episodes of illness. Identified protections include, for example, social support, and vulnerabilities include stressful environments particularly where there is a high level of personal criticism (see Figure 1.1). John Wing (1978) suggests that primary impairments, which consist of the basic processes, secondary impairments (the personal reactions to these impairments) and society’s responses, combine to produce the level of handicap. Although rehabilitation should be comprehensive and try to consider factors that lead to good or poor results, the development of this comprehensive system is likely to necessitate the identification of individual efficacious therapies that combat only one or two vulnerability factors or enhance only one or two protective factors.

The beneficial effect of any intervention is governed by traditional methodology in randomised control trials (RCTs) that emphasises a single simple outcome measure even for complex interventions. This single outcome is linked directly to the focus of therapy such as improvements in social skills following psychosocial therapy. The identification of more distal outcomes, like employment or friendships from a focused therapy often requires much larger studies for adequate statistical power. Few trials in psychosocial treatments for schizophrenia include more than 60 people in a group (Thornley et al., 1998). In addition for any analysis of the mediating variables the statistical analysis will be more complex.

There is evidence that therapies affect this biopsychosocial model and do have distal effects; for example, therapy to decrease the effects of stressful family environments has an effect on admissions to hospital (Pilling et al. , 2002a). The psychiatric community also provides advocacy for people with psychiatric problems to reduce the effects of life events and chronic difficul-ties through its enhanced support. This reduces the effects of stressful experiences which occur relatively often for people who have reduced finances irrespective of any symptoms that might interfere with coping. This advocacy is clearly laid out in some of the Assertive Outreach models of care and has been shown to have effects on admissions to hospital. But what is clear from the stress-vulnerability model is that there are a variety of stress and coping responses that are dependent on the personal resources of the individual concerned. One such personal resource is thinking skill. No one in the psychiatric community would argue that this is not a basic difficulty or primary impairment associated with a diagnosis of schizophrenia. However, researchers and health professionals, although noting the importance of these cognitive difficulties, have spent little time developing therapies that could directly affect these problems.

The model shown in Figure 1.1 illustrates the development of symptoms through a complex interaction with vulnerability, resilience and stressor factors. It is clear that an intervention for cognitive skills might have an impact at several different points. It could increase processing capacity, reduce information processing overload, change reasoning biases and affect appraisals of information, given that our model of CRT aims to change metacognition. Social and occupational functioning in this symptom-focuse...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• Figures
• Tables
• Acknowledgements
• Part I The development of therapy
• Part II Improving cognitive processes
• Part III The process of therapy
• References