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NEUROPSYCHOLOGICAL REHABILITATION
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A Baddeley 1.0, Emslie 1.08, Goodrich 0.75, Murre 0.38, Nimmo-Smith 0.75, Robertson 3.34, Wilson 3.0, Balleney (SO) 1.08, B Baddeley (ASO) 0.42, H Baddeley (HSO) 0.14, Bruce (SO) 0.17, Buxton (SO) 0.24, Evans (HSO) 2.5, Ivani-Chalian (SO) 0.42, Jolliffe (ASO) 0.25, Kolodny (SO) 0.06, Pike (SO) 0.17, Ridgeway (HSO) 2.14, Shiel (HSO) 2.25, Toplis (ASO) 0.52, T Ward (HSO) 2.17
Total Person Years: Scientists 10.5; Research Support 12.4
Abstract
Objectives
The rehabilitation programme has sought to: (a) develop new theoretically-derived treatment techniques, (b) produce new theoretically-derived assessment procedures for identifying and monitoring cognitive deficits, (c) understand the natural history of recovery from brain injury, and (d) develop a theoretical framework for understanding the pattern of recovery of neuropsychological functioning.
Scientific progress and achievements over the past five years
In the area of memory and learning we have demonstrated tangible clinical benefits of applying principles of cognitive psychology to memory and learning deficits. Specifically, we have (a) shown that errorless learning is superior to trial-and-error learning for patients with severe memory problems; (b) shown that it is possible for patients in coma following traumatic head injury to learn simple tasks; (c) begun evaluating a new electronic memory aid; (d) developed assessment procedures for predicting everyday cognitive problems and for monitoring change over time; and (e) followed up a group of brain injured people in order to document the natural history of recovery from brain injury.
In the field of attention and cognitive control we have outlined a number of mechanisms by which recovery of neuropsychological function can take place, and demonstrated that improvement in unilateral neglect can be produced by capitalising on three of these mechanisms, namely: reducing inhibitory competition on the damaged right hemisphere by inducing limb activation on the left side of the body; maximising activation in the damaged hemisphere by synchronising activation in both body and extrapersonal space; increasing non-lateralised sustained attention. We have also developed new methods for tackling executive and sustained attention problems following closed head injury, and for assessing theoretically distinct types of attention.
Future plans for the next five years
We propose to maintain the balance between theoretically based experimental work and clinically driven therapeutic research. Building on the work of the past four years, we plan to improve function by incorporating principles of recovery, implementing new strategies to improve learning, and modify existing technologies to make them suitable for brain injured people. Specifically, in the field of memory and learning we plan to evaluate a new day rehabilitation unit for adults with non-progressive brain injury; (b) develop the work on errorless learning (in collaboration with Baddeley) by addressing some of the theoretical questions arising from earlier studies and by extending the clinical applications of this method; (c) continue with the evaluation of a new electronic memory aid; (d) continue to develop new assessment procedures for predicting performance in everyday life and monitoring change in clinical contexts; (e) extend understanding of the natural history of brain injury through following head injured people and people with Huntington's Disease; and (f) collaborate with Nimmo-Smith in developing methodologies to evaluate recovery and change over time.
In the area of attention and cognitive control we plan to work closely with Duncan, in applying the integrated competition hypothesis to recovery and rehabilitation. Specifically, we will: (a) model recovery of function in several different deficits; (b) examine blood flow consequences of unilateral and bilateral limb activation; (c) further develop clinical strategies for treating neglect using limb activation; (d) examine the role of limb activation in anosognosia, global versus local processing, sustained attention and input versus output neglect; (e) evaluate further attentional control training and determine its effects on sustained and selective attention; (f) develop ways of improving sustained attention in unilateral neglect patients, including pharmacological methods; (g) examine frontal cerebral perfusion in good versus poor outcome closed head injury; (h) determine the blood flow consequences, if any, of goal neglect training; (i) develop theoretically-based clinical measures of aspects of attentional function, especially non-visual neglect.
Implications for improving health, health care and wealth creation
Our research has both direct and indirect implications for the care of brain injured people. New treatment methods developed by Wilson and Robertson have begun to influence clinical practice and are being implemented in rehabilitation programmes. Developing objective and theoretically sound assessment procedures that are also related to tasks met in everyday life has encouraged more effective identification and more relevant treatment of neuropsychological problems following brain injury. A clearer understanding of the natural history of recovery should result in better prediction of recovery that could in turn influence allocation of resources and thereby benefit the work of health economists. All our research has potential for reducing the cost of health care through improved diagnoses, better treatment and improved targeting of rehabilitation services. Finally, appropriate rehabilitation of the kind we are seeking to encourage by our work is likely to result in greater numbers of people returning to work and thus alleviating financial and other strains on health care and social services.
NEUROPSYCHOLOGICAL REHABILITATION OF MEMORY AND LEARNING DISORDERS (Baddeley, Emslie, Wilson)
Introduction
Neuropsychological rehabilitation is concerned with the assessment, treatment and natural recovery of brain injured people. The fundamental cognitive functions that are crucial in the relearning of new skills or compensatory strategies within rehabilitation are attention, memory and learning. In the APU's research into rehabilitation of these functions, Robertson has focused on attention (see his section in this programme of the report) and Wilson on memory and learning.
Essential to research into neuropsychological rehabilitation is access to patients requiring assessment and treatment so that the interface between research and practice is optimised. The past four years have been a transitional period for the Rehabilitation Research Group, as we have been attempting to set up a new programme while remaining outside a clinical setting. To compensate, group members have made use of prior contacts and have worked with more distant collaborators than would normally be regarded as ideal. Despite these difficulties, progress has been made in the major areas of assessment, treatment, and the natural history of recovery from brain injury. Further substantial progress is expected when the group has been relocated into a clinical setting.
A. Remediation of Disorders of Memory and Learning
Wilson and Robertson's earlier work has shown that methods found to enhance attention, memory and learning in non brain-injured people can also help those with deficits resulting from neurological insults. Effects for brain-injured individuals are, however, typically smaller, and there are limitations to the application of normal methods. There would appear to be two main approaches when treating people with memory and learning difficulties. One is to develop new teaching methods to enhance learning, and the other is to capitalise on and improve new technological equipment so that it is more suitable for use with brain injured people.
A1. Errorless Learning in the Rehabilitation of Memory Impaired People: Errorless learning is a teaching technique whereby people are prevented, as far as possible, from making mistakes while they are learning a new skill or acquiring new information. Instead of teaching by demonstration, which may involve the learner in trial-and-error, the experimenter/teacher presents the correct information or procedure in ways that minimise the possibility of erroneous responses.
In one group study (5.8), and several single case studies (5.51), it was demonstrated that people with severe memory disorders learn more successfully with an errorless learning strategy. People with poor episodic memory tend to rely upon implicit memory, which is poor at error elimination. Errorless learning has proved effective over a range of tasks (including learning names, learning new information, recognising pictures and programming an electronic aid), over a range of diagnostic groups (head injury, stroke, encephalitis and Korsakoff's syndrome) and over a range of periods post insult (from Post Traumatic Amnesia to 12 years post onset).
A2. Developing and Modifying New Technologies: Much of the work in memory rehabilitation involves teaching people to compensate for their impairments by employing aids such as diaries, tape recorders, filofaxes, electronic organisers, computers and so forth (5.15, 5.46, 5.76, 5.80). Work in this area of rehabilitation is complicated by the fact that remembering to use an aid is, in itself, a memory task. Thus brain injured people may forget to employ the aid; they may also experience problems in programming an aid or using it in a systematic and efficient manner. We have recently begun a collaboration with Hersh and Treadgold (California) to evaluate the effectiveness of NeuroPage, a simple and portable paging system with a screen that can be attached to a waist belt. NeuroPage uses an arrangement of micro-computers linked to a conventional computer memory and, by telephone, to a paging company. The scheduling of reminders or cues for each individual is entered into the computer and, from then on, no further interfacing is necessary. On the appropriate date and time the reminder is transmitted to the individual. All the individual needs to learn is to press one button. Preliminary results look encouraging.
A3. Learning in Coma: This work was undertaken with colleagues in Southampton (5.43). During an observational study of how patients with severe head injury recover functional skills, we noted that some patients could be prompted to remove a cloth placed over their face while still in coma. We designed three experiments, using backward chaining as the teaching method, to assess the possibility of learning in coma following severe head injury. The results, suggesting that comatose patients are capable of learning simple tasks, have both theoretical and practical relevance. Theoretical implications include the role of conscious awareness in learning and the processes by which comatose patients can learn. Practically, it might be possible to harness such learning in order to prevent some commonly observed complications arising from severe head injury, such as the adoption of postures that increase the likelihood of developing contractures.
A4. Providing a Resource for Clinicians and Relatives: This aspect has developed as a natural outcome of our reported work in the field of rehabilitation. Advice is given to several groups including professional bodies, clinical workers, medical personnel and relatives, and consists of information on the nature of rehabilitation, varieties of rehabilitation available and further contacts in the field. Workshops on rehabilitation have been presented in Britain and 14 other countries.
B. Assessment
B1. Developing Assessment Procedures for Predicting Performance in Everyday Life: Assessment under realistic conditions is important for predicting behaviour outside the laboratory or clinic, and also for its acceptability to both patient and therapist. One test which fulfils both these conditions is the Rivermead Behavioural Memory Test (Wilson, Cockburn & Baddeley, 1985). The RBMT has been shown to predict independence in daily life (5.44, 5.47) and is widely used by occupational and speech therapists as a tool to (i) predict how patients function in daily life, and (ii) monitor change over time. The test is used in 17 countries and has been translated into 11 languages. A children's version appeared in 1991 (5.55) and has been given to adults with Downs Syndrome (5.54) as a preliminary exploration into the suitability of the test for comparing Alzheimer's disease with the ageing effects seen in Downs Syndrome. We have also piloted an extended and more difficult version of the original RBMT in order to avoid ceiling effects when testing people with more subtle deficits (5.13).
A major area of current interest in research and rehabilitation is executive functioning and the deficits which appear following damage to the frontal lobes. Patients with DysExecutive Syndrome (DES) are likely to be impulsive and distractible, to have problems using feedback, and to behave inappropriately in social situations. They are among the most difficult of all brain injured patients to treat. Traditional tests used to assess problems in DES are unrepresentative of everyday tasks, and therefore sometimes yield normal scores in people who continue to experience problems in everyday life. Using theoretical models of Baddeley and Hitch (1974) and Shallice (1982), and in collaboration with Alderman (Northampton) and Burgess (London), we have designed a test battery to assess executive functioning. The Behavioural Assessment of Dysexecutive Syndrome (BADS, in preparation) contains tasks that are more representative of executive functioning in everyday life. Current work is funded by an EARHA/LORS grant. Emslie is currently collecting norms on the six subtests of the BADS together with a questionnaire which is given to patients and close relatives. Our eventual aim is to employ the test to help set rehabilitation goals. It could, for example, be used to evaluate the effectiveness of the Goal Neglect training described by Robertson in this report.
The BADS is primarily concerned with planning, organisation and problem solving, while the complementary Test of Everyday Attention (TEA) (5.86) focuses on various aspects of attention.
B2. Developing New Clinical Measures for use in Neurological Contexts: In addition to providing ecological assessment procedures, there is a need to develop new measures to assess impaired functions in brain injured people within the clinical context. One example is our attempt to develop a better measure of Post Traumatic Amnesia. PTA refers to the period following traumatic brain injury when the patient is no longer in coma but is confused, disorientated, suffers from retrograde amnesia and has difficulty learning new information. PTA is a useful index of the severity of brain injury and one of the best predictors of outcome, but it is rarely formally assessed. Although two tests of PTA are available (Levin et al., 1979; Shores et al., 1986), these do not distinguish between genuine PTA and more chronic memory impairment.
One study carried out with colleagues in Southampton (5.52) was designed to see how people in PTA differ from those with amnesic syndrome and from those with chronic memory impairment. All groups experienced memory problems, although those with the amnesic syndrome were the most severely impaired. People in PTA were poorer than the other groups on verbal fluency tasks, backward digit span, simple reaction time and accuracy of comprehension. We are now continuing the work on PTA with Boismeir (Neurosurgery, Addenbrooke's), supported by a grant from EARHA. Our concern is to assess and characterise the pattern of recovery from PTA. The analyses are being conducted with the help of Nimmo-Smith (APU).
Prospective memory, remembering to perform a pre-specified action, is another function that is subject to impairment following brain damage and is of interest to both theorists and practitioners. To date, the only published test to include standardised measures of prospective memory is the RBMT. Evans, Wilson and Baddeley are in the process of developing a test of prospective memory in which subjects read a story and while doing so are supplied with instructions, inserted in the story, relating to actions they have to remember to perform at a later point. The test is highly sensitive to the effects of age.
B3. Advising on Assessment Measures for Clinical Researchers: A number of other centres have sought our advice on the development of effective assessment procedures for their studies. Wilson and Baddeley are on the Advisory Committee for the Department of Health National Brain Injury Study, which approached us with a request to provide additional sensitive measures to assess the effectiveness of rehabilitation programmes. Other requests for advice on neuropsychological measurement include one concerned with a multicentre drug study by Wellcome, which attempts to prevent some of the undesirable consequences of head injury that develop immediately after insult. Wilson is also consultant to a study examining the effects of HIV infection in homosexual men (5.26), and in people with haemophilia. Finally, we provide a resource service for other professionals as to the most appropriate tests to use in specific circumstances.
C. The Natural History of Brain Injury
This work includes studies of the natural history of recovery of non-progressive disorders and a specific examination of the pattern of decline in Huntington's disease. Knowledge of the natural history of a neurological condition is important for understanding a disease and its pattern of recovery; such studies must involve longitudinal approaches with repeated measures over time. Data from these may present statistical and methodological challenges which we are addressing with the help of Nimmo-Smith (APU).
C1. Long-Term Follow-Up of Brain Injured People 5-15 Years Post Insult: Since 1988 Wilson has been engaged on a series of follow-up studies of patients first seen between the years 1979 and 1986. The main aims were: (i) to see how neuropsychological functioning changes over time, (ii) to collect information about long-term vocational and social outcomes for brain injured people, (iii) to identify the main compensatory strategies used by people with brain injury, and (iv) to identify characteristics which lead to poor or good outcome. A subsidiary purpose was to identify patients with theoretically important neuropsychological syndromes.
The first follow-up study was of 54 people referred for memory therapy between the years 1979-1985 (5.44, 5.46). Most subjects were using more compensatory strategies at follow-up than at the end of rehabilitation; 30 per cent had shown noticeable improvement in their scores on a standardised memory test; 36 per cent were in paid employment; and 20 per cent were living in institutional care.
The second study looked at a group of seven people originally referred for remediation of acquired disorders of reading (5.49). The main finding here was that, despite some significant gains during rehabilitation, subjects showed little further improvement following discharge, and only three subjects read for pleasure.
The third study is currently following people with very severe intellectual impairments. These were operationally defined as initially untestable on standardised neuropsychological tests for adults, and were originally assessed on tests for children with learning difficulties. A subgroup of patients with anoxic damage will be written up as a separate group due to their significant visuo-spatial and visuo-practic difficulties.
A number of patients with theoretically important neuropsychological syndromes have been identified; the long-term follow-up research has enabled us to isolate and assess syndromes that were previously difficult to detect because of widespread damage in the early stages after insult (5.50, 5.53, 5.60).
C2. The Use of Functionally Relevant Assessment Procedures in Predicting Long-Term Outcome after Severe Head Injury (Wilson, McLellan, Evans, Pickard): In a previous project funded by the MRC (Wilson, McLellan & Campbell, 1987) we developed a set of scales to assess recovery of cognition, awareness, communication and motor skills (5.84). These scales, based on the assessment of 88 patients, have proved useful in identifying patterns of recovery of function in each of the skill areas (5.21). In the present project, we are testing the sensitivity of the scales for predicting outcome three years later. In collaboration with Shiel (Southampton), we have traced and reassessed 40 of the original sample. Each subject has been reassessed on tests of neuropsychological functioning, motor skills, activities of daily living and social functioning. We are at present analysing results with the help of Nimmo-Smith (APU).
C3. Change over time in People with Huntington's Disease (HD): In collaboration with Ward and Shiel (Southampton) we are seeing a group of people who attended the genetics clinic for screening for HD. All subjects are being followed longitudinally to see how memory and executive function change.
FUTURE PROPOSALS
Introduction: Neuropsychological Rehabilitation of Brain Injured People with Memory and Learning Disorders
This programme of research is concerned with the development and evaluation of new rehabilitation methods. Successful rehabilitation depends on combining an understanding of the patient's deficits with appropriate treatment and reintegration into the community. Because of recent changes in the National Health Service, our neuropsychological rehabilitation programme has had to proceed in rather a piecemeal fashion. This looks set to change, however, with (a) the Rehabilitation Research Group's move to Addenbrooke's Hospital later this year, and (b) the strong possibility of a new neuropsychological rehabilitation day unit to be set up by Lifespan, the NHS Trust responsible for community care, with Wilson as scientific director. Such a unit would incorporate the best currently available treatment, would encourage the development of new treatments as well as new ways of evaluating these, and would become a unique establishment for bridging MRC and NHS contributions to treatment research. Proposed research for the next five years would be centred largely around the new unit and the new development at Addenbrooke's Hospital. It would build on the work of the past four years and would also include evaluation of the new service's efficacy and cost effectiveness at a broader level.
A. Evaluation of Treatment Programmes and Therapeutic Strategies
A1. Evaluation of a New Neuropsychological Rehabilitation Unit: Lifespan Trust is planning to open a day rehabilitation unit for adults with non-progressive brain injury. The unit would cater for 15 patients at any one time, each of whom would attend five days a week for approximately four months. All patients would receive both individual and group sessions, and the programme would be modelled on the successful centres that have been operating for several years in New York, Phoenix and Copenhagen. Such a unit, staffed by carefully selected therapists, would offer a unique opportunity for the development and evaluation of new treatment procedures. It would provide access to a wide range of potentially interesting neuropsychological patients who would be available for a sufficiently long time to make detailed single case studies possible. It would thus facilitate the basic research of the APU as well as provide a mechanism whereby such research could be applied within a clinical context, thereby encouraging its transfer to more widespread use within the Health Service.
The opportunity exists to evaluate the efficacy and cost effectiveness at a more general and comprehensive level through collaboration with Stilwell (Warwick). Currently in charge of the Department of Health National Brain Injury Study, Stilwell has agreed to collaborate on the design of this study and would provide access to the National Databank for the provision of control data.
A2. Errorless Learning: Earlier work demonstrated the superiority of errorless over errorful learning for people with severe memory disorders (5.8, 5.51, 5.74). While it is already clear that errorless learning can be a very effective way of teaching amnesic patients, we still have a relatively limited understanding of its theoretical underpinning. It is not clear, for example, whether the effect depends entirely upon the implicit component of learning. This issue has substantial implications for the range of tasks to which the technique might be applied, and to the question of whether it could usefully be combined with principles that optimise explicit memory, such as the utilisation of richer and deeper encoding. One feature of the studies carried out so far is the tendency for amnesic patients to show marked forgetting over relatively brief delays once the errorless testing method has been abandoned. This raises practical questions such as the optimal degree of over-learning, and also theoretical issues such as the nature of the forgetting. Finally, because the phenomenon suggests the possibility that implicit and explicit modes of learning may be differentially subject to interference effects, it has substantial implications for the general issue of the role of interference in learning and remembering. This aspect of the work will be pursued in a collaboration between Wilson and Baddeley and will form part of a grant proposal by Baddeley.
A3. Developing New Technologies: The preliminary encouraging results from the NeuroPage project will be pursued more systematically. We (Wilson, Evans, Malinek) are seeking funding from the NHS Research and Development Fund, and will continue the collaboration with Hersh and Treadgold (California), the designers of NeuroPage. A combined single case design (using a multiple baseline across subjects) and a two-group design is proposed.
A4. Remediation of Semantic Memory Disorders: In an earlier study (5.60) it was noted that semantic memory problems are not uncommon in brain injured patients. Some of these patients have severe episodic as well as semantic memory deficits whereas others have minimal episodic memory involvement. The question arises as to whether this group of people can relearn semantic concepts. Indeed, it might be possible to reteach some semantic information even to those with severe amnesia. Systematic attempts at remediation of semantic memory disorders might shed light on some controversial theoretical issues, including the distinction between deficits of storage vs. access, and whether this distinction might be systematically related to the aetiology of semantic memory disorders.
We propose to investigate the possibility of reteaching semantic information to patients with (i) reasonably intact episodic memory functioning, and (ii) severely impaired episodic memory functioning. We shall attempt to determine whether recent findings of Snowden, Griffiths and Neary (1994) apply to our patients. Snowden et al. demonstrated that, in patients with semantic dementia (i.e. those with progressive disorders), personally relevant semantic information was markedly better preserved than less personally meaningful information. Because of the relative scarcity of suitable local patients, this study will make use of single case experimental designs.
B. Assessment
B1. Development of Assessment Procedures for Predicting Performance in Everyday Life: As part of our aim to provide clinically acceptable tests that predict performance in daily life, we will continue to work on the tests described in the Report for 1990-1994. We need to demonstrate the suitability of the extended version of the Rivermead Behavioural Memory Test (5.13) for patients with very mild memory deficits. The Behavioural Assessment of the Dysexecutive Syndrome will probably be ready for publication early in 1995, following studies with brain injured people and people with schizophrenia (in collaboration with McKenna, Cambridge). The BADS is likely to prove useful as an outcome measure for treatment of people with deficits of attention, planning and problem solving. We plan to utilise existing links with colleagues in Europe to demonstrate this aspect, and to collaborate with Robertson and Duncan in their study of goal neglect (see their sections of this report).
We also plan to develop some preliminary work on a more qualitative prospective memory test designed to predict use of external memory aids in daily life, which can be used to see where and how compensatory failures occur. It could also be used as an outcome measure to evaluate memory rehabilitation programmes. Chiapello and Prigatano (Phoenix, Arizona) are collaborating on this project.
B2. Developing New Clinical Measures for Use in Neurological Contexts: The analyses of the Post Traumatic Amnesia study should be completed by late summer 1994. The next step will be to select the most sensitive tests from the original battery as a brief assessment tool to identify those patients who are in or out of PTA, in order to help with questions about discharge or referral to rehabilitation. In collaboration with Pickard (Cambridge) and others in Neurosurgery, we will also determine whether the new brief battery is appropriate for those with a mild head injury and a shorter PTA. In collaboration with Robertson and Murre, we intend to develop a neuropsychological model of PTA based on attentional and executive processes (see Robertson's section of this report).
We described above the pilot study of a prospective memory test involving reading a story in which several instructions are embedded. This test is to be modified for use as a clinical and research tool. The tasks that subjects are requested to perform have been chosen to tap different aspects of prospective memory, namely (i) time- versus event-based tasks, (ii) pulse versus "step" tasks, (iii) simple versus complicated tasks, and (iv) habitual versus episodic tasks. In addition, there will be a manipulation involving the number of tasks subjects have to remember at any one time. We know from the pilot work that the test is sensitive to age-related differences. We now plan to develop the test so that it is useful for assessing prospective memory functioning in patients with brain injury. We will also evaluate the relative effectiveness of computer versus paper-and-pencil versions, look at parallel-form reliability within each version, and use the new test to examine the relationship between prospective memory, retrospective memory, and other cognitive functions. Finally, the extent to which prospective memory failures contribute to the everyday problems of brain injured people will be examined.
C. Natural History of Brain Injury
C1. Reliability and Validity of Functionally Relevant Assessment Scales for Severely Head Injured Patients: In a previous study (5.21, 5.84), we devised scales to monitor the improvement of cognitive skills, social behaviour, motor ability and self care in recovery from severe head injury. The main advantage of these scales is that they rely on behavioural observations of skills used in everyday life, and therefore have implications for care and rehabilitation of head injured people. The next steps, to be conducted in collaboration with McLellan and Shiel in Southampton, are (i) to ensure that the scales are reliable and valid, and (ii) to determine whether the scales can be used to identify goals for treatment.
C2. Change Over Time in People with Huntington's Disease: In collaboration with Ward and Shiel (Southampton) and Kopelman (London), Wilson (APU) is seeking funding to employ a full-time assistant to (i) investigate the way in which memory, intelligence and other functions are affected in the early stages of HD, and (ii) follow up the original sample to clarify the manner of dissolution of different cognitive functions. In the long term this should lead to improved counselling for patients and relatives and the development of more appropriate management and rehabilitation strategies for families with HD members.
C3. Development of Methodologies to Evaluate Recovery and Change Over Time: Outcome studies present a number of methodological challenges. For example, they may include important data obtained through complicated multiple repeated observation schedules at irregular times (e.g. 5.84) but with significant amounts of missing data, making analysis problematic. Nimmo-Smith, in collaboration with Wilson, Evans, Emslie and Baddeley, proposes to capitalise on and adapt the growing body of techniques for analysing 'messy data' from various fields within social science and health care. Applying these methods to the modelling and analysis of clinically obtained neurological data will enable the evaluation of trends and interventions as well as the relevance of a variety of factors in the presence of many covariates. In addition, results are likely to help improve designs for outcome studies.
NEUROPSYCHOLOGICAL REHABILITATION OF ATTENTION AND ASSOCIATED DISORDERS (Goodrich, Murre, Robertson)
Introduction
Attention is not a unitary phenomenon, and recent PET and other studies have suggested a set of possible brain circuits which may be responsible for different supramodal attentional processes in the brain. Many types of brain damage cause attentional problems, and attention may have a privileged role in recovery of function following damage to the brain (5.68 ). Attention is therefore of great theoretical and clinical importance, and the aims of our current research are to develop methods of assessing different types of attention, to determine the nature of these mechanisms and their interactions, and to find viable clinical methods of treating these disorders. This report covers work carried out partly in the Neuropsychological Rehabilitation Programme of the Unit's work and partly in the Attention and Cognitive Control Programme. The overlap is however substantial, and therefore the entire programme of work is presented under the Neuropsychological Rehabilitation Programme.
A. A Theoretical Framework for Attention and for Recovery of Function (Robertson, Murre, Ward, Ridgeway)
A1. A Theoretical Framework for Attention Disorders: This work dovetails with Duncan's (see his section of this report, in Attention and Cognitive Control). We concur with his view that selection takes place through a process of competition within the visual and other modalities, via mechanisms such as the attentional template. However, the thrust of our research is to explore the possible existence of additional supramodal attentional control systems which come in to play when tasks are not automatic or overly simple.
PET scan research suggests the existence of several different attentional systems in the brain which have specialised control functions independent of any particular sensory modality. These include a system for selection, a system for sustained attention, and an orientation system whose role is to shift attention in space. Standardised clinical instruments to measure these different aspects of attention do not yet exist, and so the Test of Everyday Attention (TEA) (5.86) was developed, based as much as possible on familiar everyday materials such as maps and telephone directories. Factor analysis of data from 150 normals in the standardisation sample produced a factor structure which was indeed strongly related to the theory outlined above. Assessment in a group of 120 CVA patients found highly significant correlations between several of our measures of attention and functional status in everyday life, suggesting a clinical utility of the test in addition to its theoretical coherence. We have shown also that recovery of physical independence between two and eight months post-stroke is strongly predicted by our two-month TEA attention measures. Furthermore, we obtained evidence -- previously unreported in the literature on closed head injury -- for a deficit in sustained attention, and found the TEA to be very sensitive to the effects of closed head injury.
This research has close links with the work of Wilson on the Behavioural Assessment of Dysexecutive Syndrome (BADS) Test (see Wilson's section in this programme).
A2. A Theoretical Framework for Recovery of Neuropsychological Function: This is a recent area of collaborative work between Robertson and Murre in which we have attempted to develop a theoretical framework for recovery of function. The framework is partly designed to account for the experimental work on neglect and attention outlined below, and partly informed by connectionist models of neural reorganisation following localised lesions. In this framework, we exclude those compensatory mechanisms which Luria and others have proposed to underlie much recovery of function, and have instead concentrated on processes which may allow more intrinsic recovery of function in the lesioned modules themselves. Our model proposes four possible mechanisms of recovery of function: a) Increasing activation of malfunctioning circuits/representations by reducing competition from adequately functioning circuits/representations; b) increasing integration of malfunctioning circuits/representations to produce a summation of activation; c) improving performance of malfunctioning circuits by increasing arousal/sustained attention; d) improving strategic control over behaviour through implementing strategies for selecting relevant goals, as well as for rapidly encoding and retrieving these goals. These possible mechanisms provide the framework within which the past and future research programmes are formulated.
B. Improving Function by Reducing Competition from Non-impaired Circuits (Robertson, Goodrich)
Much brain activity is competitive, and hence a circuit weakened by damage is at risk of even greater impairment by inhibition from competitor circuits. Such competition may be especially likely following unilateral brain damage in stroke, when the undamaged hemisphere can inhibit the damaged hemisphere's function via connections across the corpus callosum.
B1. Experimental Studies of Limb Activation in Unilateral Neglect: In patients with inattention for the left side of space, left hand and left leg movements can significantly reduce neglect on reading and cancellation tasks (5.2, 5.36). Neglect patients' tendency to veer to the right when walking can also be corrected by having them perform left hand movements while moving (5.41). Our explanation of these findings is that the left limb movements increase activation of the damaged hemisphere and thereby reduce competition from the intact hemisphere. The close connection between action and attention in the primate brain suggests that the limb movements may activate linked attention circuits as well as motor circuits in the damaged hemisphere, thus leading to increased activation. A further study (5.39) showed that the beneficial effects of left hand movements could be eliminated when simultaneous identical right hand movements were made. This finding, explicable in terms of motor extinction, has considerable implications for the way in which physiotherapy is carried out with neglect patients. These results (a) can be integrated into the theoretical model of competition and extinction within attention systems proposed by Duncan (this report); and (b) find some parallels in the work of Wing on biofeedback methods for balance training in stroke patients (described in the Perception and Action programme of this report).
B2. Clinical Implementation of Limb Activation in the Treatment of Unilateral Neglect: The short-term experimental effects of limb activation on neglect were incorporated into a clinical treatment regime, using an electronic device, "the Neglect Alert Device". This device emits randomly spaced sounds that are terminated by activating switches with movements by the affected side of the body. The aim of this treatment is to increase left limb activation in a variety of everyday situations. Three single case studies showed enduring clinical improvements, both on neuropsychological tests and in everyday life function, as a result of this procedure (5.40). The clinical effect has subsequently been replicated by a team not involved in the original development of the treatment procedure.
C. Improving Function by Summating Activation of Mutually-Facilitatory Circuits (Robertson, Goodrich)
While some circuits are mutually inhibitory and competitive, others are facilitatory, such that synchronous activation may produce a summation of activation sufficient to yield significant improvements in function. Our research suggests that attention circuits for different spatial arenas have a facilitatory relationship. The work of Rizzolatti and others has shown that space can be divided into three independent yet related arenas: body space, external reaching space, and external far/locomotor space. Different brain circuits control attention to these different spatial areas, and lesion studies reveal dissociations between all of these spatial systems, with some patients for example showing unilateral neglect within body space but not external space, etc. We hypothesised that synchronous activation of these overlapping circuits might lead to improvements in unilateral neglect. Goodrich (see her section in the programme on Attention and Cognitive Control) has also investigated the possibility that, in the sensory domain, improved detection of neglected stimuli may occur when additional sensory modalities are used to signal the presence of these stimuli.
C1. Personal and Extrapersonal Space in Limb Activation: A beneficial effect on unilateral left neglect was produced by left hand movements made in left hemispace, but not by either left hand movements in right hemispace or right hand movements in left hemispace. Passive movements of the left hand in left space also had no impact on neglect, and we concluded that it was the synchronised activation of the left representational fields for both personal and reaching space which resulted in combined activation sufficient to improve attention to the neglected side (5.36, 5.37, 5.39).
C2. Gripping versus Pointing in Unilateral Neglect: The nature of the response made to the left side of space may affect neglect, if certain responses activate additional motor circuits. In collaboration with Hood (University of Cambridge), we studied neglect patients on tasks involving either pointing to or lifting of metal batons. Pointing to the perceived centre of the baton produced relatively more neglect than a movement towards the baton with the intention to pick it up. This suggests that the activation of motor circuits related to planning complex movements improves attention to the neglected side, possibly via mechanisms similar to those involved in the limb activation studies described above.
D. Improving Function by Increasing Arousal/Sustained Attention
Arousal and sustained attention are central to recovery of function following brain injury, and hence improvement of sustained attention deficits is potentially important for rehabilitation. The sustained attention system may have a particularly direct modulating role on the posterior attention orientation system implicated in neglect, possibly via the noradrenaline pathways which are reported to be more strongly represented in the right hemisphere of the brain. Increasing arousal and sustained attention may therefore have both general effects on neuropsychological performance and specific modulating effects on unilateral neglect. This argument allows us to predict both deterioration in neglect in conditions where sustained attention is impaired, and improvements in neglect under conditions where it is enhanced.
D1. Attentional Load and Unilateral Neglect: We showed that neglect could be worsened by purely auditory-verbal attentional manipulations (5.34). We also found support for the view that the lateralised attentional disorders characteristic of neglect were strongly influenced by non-lateralised attentional factors (5.66): For instance, loading auditory-verbal working memory by a random number generation task produced significant greater unilateral neglect than a control condition (5.34). The mechanism for this interference may be degradation of the sustained attention required for the lateralised scanning tasks caused by the load on working memory. Further evidence for a strong role of non-lateralised attention in unilateral neglect comes from our study showing that left neglect patients at times show paradoxical right neglect, due to the partial implementation of a compensatory leftward scanning strategy in the context of impaired non-lateralised attention (5.35).
D2. Interactions between Sustained Attention and Unilateral Neglect: Degrading sustained attention may worsen neglect, but can neglect be improved by enhancing sustained attention? In a study carried out with colleagues in Stockholm and Southampton, eight patients with unilateral neglect were trained to improve their sustained attention with a self-instructional procedure which capitalises on intact phasic arousal, i.e., alerting in response to salient or novel external stimuli. The rationale of the training is that this intact capacity for exogenously oriented attention can be harnessed to bring the phasic response under endogenous, verbal control. Using some of the measures developed for the Test of Everyday Attention, we obtained statistically significant improvements in both unilateral neglect and sustained attention as a result of this training, with duration of the effects ranging from 24 hours to seven days (5.59) . This finding provides strong, counter-intuitive evidence for an intimate link between two of the attentional subsystems described above, with therapeutically promising consequences.
D3. Attentional Control Training: Attentional control training involves training a subject to detect when attention has strayed from a target stimulus -- the breath -- and to redeploy attention back to the target. We have applied this method, which Teasdale (see his section in the Cognition and Emotion programme of this report) has been exploring with recovered depressives, to patients approximately one year after closed head injury. In a randomised control pilot study, we found significantly greater reductions in problems of self reported memory, attention and mood in the trained over the untrained group. These beneficial effects may arise because of improved sustained attention, reduction in attention-occupying distressing thoughts, or indeed both of these. The advantage of this method of training sustained attention is that the metacognitive training is both unobtrusive and intrinsically rewarding, and may be more widely generalisable than material-specific attention-training procedures which we have developed (5.57)
E. Improving Function Through Enhanced Goal Encoding and Goal Management (Robertson, Duncan)
Attention overlaps considerably with the concept of executive function, and Duncan has argued that the ability to encode relevant behaviour goals is central to executive function. People who fail to do this may show "goal neglect", and this impairment may arise because of a failure actively to encode or a difficulty in maintaining relevant goals in working memory, in the face of competition from other possible goals.
E1. Goal Neglect Training: We have begun to pilot a procedure for reducing goal neglect in closed head injury patients with poor executive control. The training involves teaching a general problem-solving algorithm, together with mnemonic and other strategies aimed at increasing the efficiency of goal encoding in working memory. So far, pilot single-case data on three cases are available, but the series is not yet complete.
FUTURE PROPOSALS
Introduction: Neuropsychological Rehabilitation of Attention and Associated Disorders
We propose in the next five years to maintain the balance between theoretically-based experimental work and clinically-driven therapeutic research. It is in the nature of rehabilitation research that tractable clinical effects must at times precede the experimental analyses and theoretical justification of these effects. The two approaches must go hand in hand if neuropsychological rehabilitation is to develop as a scientifically based discipline.
Our research will concentrate on trying to improve function, experimentally in the short term as well as therapeutically in the medium term, based on the principles of recovery described above, namely a) competition/extinction, b) integration, c) arousal and c) executive control. These principles will be applied to the following clinical disorders of attention: unilateral neglect; dysexecutive syndrome following frontal lobe lesions; sustained attention deficits following right hemisphere lesions; disorders of selective attention, attentional switching and divided attention following closed head injury and other lesions.
Finally, there is a strong overlap between this clinically-based research programme and the experimental and physiological analyses of visual attention and executive functions described by Duncan (see his section of this report), and we plan to integrate our future work with Duncan's research programme wherever possible. As shown already in our work on both limb activation and goal neglect training, each programme stands to benefit substantially from collaboration with the other.
A. A Theoretical Framework for Attention and for Recovery of Function (Robertson, Murre, Wilson, Wing, Nimmo-Smith)
A1. A Theoretical Framework for Attention Disorders: The attentional measures and concepts developed in the previous programme will be applied, in collaboration with Wilson, to the phenomenon of post-traumatic amnesia (PTA). Wilson (see her section of this programme) has shown attention-like measures to be the best discriminators between patients in PTA on the one hand and amnesic patients on the other. The aim will be to try to develop a model of post-traumatic amnesia based on attentional and memory processes.
A2. A Theoretical Framework for Recovery of Neuropsychological Function: We will further develop the model of recovery of function outlined above, and will apply this model to patterns of recovery in PTA as well as in unilateral neglect and other attentional disorders. Furthermore, Robertson, Wing and Nimmo-Smith will compare motor learning with the left and right hands in unilaterally lesioned stroke patients, with a view to elucidating the determinants of learning in neuropsychological recovery. These data will be examined in the light of the theoretical concepts devised by Robertson and Murre.
B. Improving Function by Reducing Competition from Non-impaired Circuits (Robertson, Duncan, Goodrich)
B1. Experimental Studies of Limb Activation in Unilateral Neglect: Assuming that PET and fMRI facilities at Cambridge become available, we plan to investigate the influence of unilateral and bilateral limb activation on cerebral blood flow (in collaboration with Duncan). We predict that unilateral left hand activation (in left neglect) will produce blood flow increases in areas beyond those usually responsible for simple motor movements, and more particularly in the right fronto-parietal cortex. We further predict that bilateral hand activation will abolish these fronto-parietal bloodflow increases, because of competitive inhibition from the intact hemisphere.
B2. Clinical Implementation of Limb Activation in the Treatment of Unilateral Neglect: Resources permitting, we propose to conduct a clinical trial of a new version of the Neglect Alert Device (in collaboration with McMillan, Wolfson Rehabilitation Centre, London) in order to determine the clinical viability and utility of the limb activation procedure developed in the previous programme. As part of the same collaboration, we hope to carry out a larger and better trial of attentional control training in closed head injury.
B3. Competition-Reduction Applied to Other Attentional Disorders: We would like to extend the competition/inhibition hypothesis to other types of disorder, such as the 'global' (as compared to 'local') processing which appears to be particularly impaired following some right hemisphere strokes. Duncan's group have suggested the possibility of competitive imbalance between global and local processing systems arising in the context of unilateral brain lesions. If this is the case, then it is reasonable to hypothesise that -- if limb activation influences lateralised attention in neglect -- it may also have a spreading effect on closely linked structures in right parietal cortex possibly specialised for global processing. We will therefore assess whether left hand movements improve global versus local processing in right lesioned patients. Similarly, we will examine whether right hand movements, by activating left parietal circuits, improve local processing in left lesioned patients.
We also plan to study whether left limb movements improve sustained attention in right lesioned stroke patients, given a right fronto-parietal specialisation for sustained attention, and will extend this paradigm to related disorders with a strong lateral bias such as anosognosia (lack of awareness) for plegia and neglect. The latter are particularly associated with right hemisphere lesions affecting the parietal lobes; hence if limb activation does indeed increase parietal function, then some improvement in sustained attention may be expected. These experiments address both conceptual issues, such as the extent to which impaired function is attributable to competitive inhibition by parallel circuits in the undamaged hemisphere, and issues of treatment, such as the extent to which extinction can be overcome to produce gains in functional performance.
Finally, we also plan to continue our research on walking trajectory, by studying blindfolded walking in normal subjects with and without hand movements. A preliminary study (5.41) demonstrated rightward veering in normal subjects under normal conditions, and very recent data suggest a much stronger effect under blindfold conditions, with a possible role for hand movements even in normal individuals. Further studies would allow us to determine whether activation effects comparable to those found in unilateral neglect are applicable to normal brain function.
Inhibition of weak representations by strong ones can also occur beyond the realm of lateralised visuo-spatial attention. Failures of selective attention in closed head injury and frontal lesions, for instance, may be described in terms of inhibition of the to-be-selected stimulus (by a competing stimulus) as the activation of the former declines in strength with habituation. This may underlie the commonly reported problem, in patients with head injury, of having difficulty following a single voice against a background of other voices, or similar difficulties in the visual modality.
We will explore the possibility of reducing competition/inhibition from to-be-ignored stimuli in at least two ways. Firstly, we will evaluate the effects of the attentional control training which has been piloted in closed head injury with promising results. Once head-injured subjects have learned to carry out the mindfulness procedure, does this result in reduced distraction from irrelevant stimuli in an auditory selection task, compared to a control condition? Secondly, we will train subjects to encode different features of a to-be-selected stimulus as a means of attempting to increase its overall activation and hence reduce competition from irrelevant stimuli. For instance, in listening to a voice among other voices, the subject would be trained consciously to encode pitch and timbre using idiosyncratic mnemonic labels (e.g. soft/harsh; shrill/growling). Parallel studies in the visual modality would attempt to improve selection by the simultaneous encoding of a number of dimensions (size, colour, shape etc.).
C. Improving Function by Summating Activation of Mutually-Facilitatory Circuits (Robertson, Duncan)
C1. Personal and Extrapersonal Space in Limb Activation: We have suggested in the previous research programme that threshold effects in reducing neglect can be obtained when mutually facilitatory but independent circuits/representations for personal and extrapersonal space are simultaneously activated. We plan further evaluation of limb activation effects under PET/fMRI, predicting that a threshold increase in activation should be observed for left limb movements made in left extrapersonal space but not for either left hand movements in right extrapersonal space, or right hand movements in left extrapersonal space.
C2. Gripping versus Pointing in Unilateral Neglect: Can this principle of synchronised activation be found in other cognitive processes? We have already established that planning to lift a metal rod evokes less neglect (as measured by deviation from centre) than pointing to its centre, suggesting that when visual attention to an area in space is combined with planning of a motor response to that same area, activation in the damaged hemisphere may be sufficient to reduce competition from the intact hemisphere. It may be however that both types of dual-system activation are purely features of impairment in a system for planning motor actions to contralesional space, and do not affect attention to stimuli in that area of space. Unilateral left neglect is now known to fractionate into "output" neglect (a difficulty in making responses to the left side of space) and an "input" neglect (a difficulty in attending to stimuli on the left side of space). Most tests of neglect confound these two categories, by requiring both attention to, and responses to, stimuli on the left side. We therefore propose to repeat previous experiments on left and right limb activation in left and right hemispace with neglect patients showing either type of neglect. If limb activation is effective only for "output" neglect, then this has both important clinical implications for targeting limb activation training and important theoretical implications for competition and inhibition between and within hemispheres.
C3. Clinical Implementation of Summation of Activation Methods: If the above experiments indeed show a differential responsivity to limb activation of the two types of neglect, then a series of single case studies will be carried out with each type of patient: limb activation training with the output neglect patients, and a training procedure which attempts to strengthen attentional representations of objects in the neglected field with the input neglect patients. If no differential effects are found, then clinical studies will focus on further evaluation and implementation of the limb activation procedures for routine clinical use.
D. Improving Function by Increasing Arousal/Sustained Attention (Robertson, Duncan, Ridgeway)
Robertson has received support (£28K over 12 months) to pursue the Attentional Control Training with stroke patients.
D2. Interactions between Sustained Attention and Unilateral Neglect: Strong connections between sustained attention and unilateral neglect were documented previously (5.59) . We propose to examine the effects of sustained attention manipulations on processes related to unilateral inattention, including anosognosia/awareness problems, global/local processing, selective attention, divided attention and attentional switching. In other words, does sustained attention supply an additional and general "resource" to all other attentional systems, or only to the posterior attention (orientation) system?
We also plan to examine the effects of certain nor-adrenergic agonists on neglect, given their action on the norepinephrine system implicated in sustained attention/arousal. This depends on obtaining the necessary funding. We also plan to examine experimentally the nature and determinants of sustained attention deficits in closed head injury and stroke, contrasting performance in conditions of high and low distraction in both auditory and visual modalities, in order to determine the relative roles of distraction, fatigue and decline in self-monitoring/self-alerting over time. Finally, we plan to measure blood flow changes using PET and fMRI during sustained attention activation procedures, as well as looking at the enduring effects on cerebral bloodflow of these activation procedures over time.
D3. Attentional Control Training: In section B3 above, we outlined proposed experimental work on Attentional Control Training. We have funding from the Stroke Association to extend the clinical evaluation of Attentional Control Training to a population of stroke patients.
D4. Psychophysiological Markers of Sustained Attention: We will attempt to develop psychophysiological markers of sustained attention during continuous performance tasks, with a view to using these markers as outcome measures in subsequent treatment studies.
D5. Clinical Implementation of Sustained Attention Training: We plan to try to develop and evaluate a procedure for implementing the sustained attention training procedure carried out in the previous programme (5.59) . This may involve a portable apparatus which delivers arousing sensory stimulation on a random basis, connected with a tape recorder which delivers appropriate self-instructions in the patient's own voice. We plan to evaluate sustained attention training delivered by this or similar methods using single-case designs.
E. Improving Function Through Enhanced Goal Encoding and Goal Management
E1. Goal Neglect Training: The main focus of this work is clinical, as it is closely tied in with the experimental and theoretical work of Duncan. However, PET and fMRI studies of components of the training strategy will be carried out, to see whether active goal encoding produces increased frontal blood flow during problem solving in frontally lesioned patients. Furthermore, closed head injury patients with poor and good functional status at one year post head injury will be compared in terms of cerebral perfusion, and we predict low frontal perfusion in the low functional status group. We have already carried out pilot work on a goal neglect training strategy, and are currently performing SPECT scans pre- and post-training, as well as neuropsychological testing. If the pilot studies continue to be successful, we plan a controlled trial of goal neglect training for closed head injury patients with MRI-defined frontal lesions. We may also carry out a similar study on elderly normals with disproportionately low performance on frontal tests.
PUBLICATIONS
Edited Books
5.1.* BADDELEY, A.D., WILSON, B.A. & WATTS, F.N. (Eds.) (in press). Handbook of Memory Disorders. Chichester: John Wiley & Sons.
5.2. ROBERTSON, I.H. & Marshall, J. (Eds.). (1993). Unilateral Neglect: Clinical and Experimental Studies. Hove, Sussex: Lawrence Erlbaum Associates.
5.3. Stachowiak, F.J., De Bleser, R., Deloche, G., Kaschel, R., Kremin, H., North, P., Pizzamiglio, L., ROBERTSON, I. & WILSON, B. (Eds.). (1993). Developments in the Assessment and Rehabilitation of Brain-damaged Patients: Perspectives from a European Concerted Action. Tübingen: Gunter Narr Verlag.
5.4. WILSON, B.A. & Moffat, N. (Eds.). (1992). Clinical Management of Memory Problems (Second edition). London: Chapman & Hall.
Refereed Articles
5.5. Aldrich, F.K. & WILSON, B.A. (1991). Rivermead Behavioural Memory Test for Children (RBMT-C): A preliminary evaluation. British Journal of Clinical Psychology, 30, 161-168.
5.6. BADDELEY, A.D. & WILSON, B.A. (1993). A developmental deficit in short-term phonological memory: Implications for language and reading. Memory, 1, 65-78.
5.7. BADDELEY, A.D. & WILSON, B.A. (1994). A case of word deafness with preserved span: Implications for the structure and function of short-term memory. Cortex, 29, 741-748.
5.8. BADDELEY, A.D. & WILSON, B.A. (1994). When implicit learning fails: Amnesia and the problem of error elimination. Neuropsychologia, 32, 53-68.
5.9. Cockburn, J., WILSON, B., BADDELEY, A. & Hiorns, R. (1990). Assessing everyday memory in patients with dysphasia. British Journal of Clinical Psychology, 29, 353-360.
5.10. Cockburn, J., WILSON, B.A., BADDELEY, A.D. & Hiorns, R. (1990). Assessing everyday memory in patients with perceptual deficits. Clinical Rehabilitation, 4, 129-135.
5.11. D'Erme, P., ROBERTSON, I., Bartolomeo, P. & Daniele, A. (1993). Unilateral neglect: The fate of the extinguished visual stimuli. Behavioural Neurology, 6, 143-150.
5.12. D'Erme, P., ROBERTSON, I.H., Bartolomeo, P., Daniele, A. & Gainotti, G. (1992). Early rightwards orienting of attention on simple reaction time performance in patients with left-sided neglect. Neuropsychologia, 30, 989-1000.
5.13. DE WALL, C., WILSON, B.A. & BADDELEY, A.D. (1994). The Extended Rivermead Behavioural Memory Test: A measure of everyday memory performance in normal adults. Memory, 2, 149-166.
5.14. EVANS, J. (1994). Physiotherapy as a clinical science: The role of single case research designs. Physiotherapy Theory and Practice, 10, 65-68.
5.15. EVANS, J.J. & WILSON, B.A. (1992). A memory group for individuals with brain injury. Clinical Rehabilitation, 6, 75-81.
5.16. EVANS, J.J., WILSON, B.A., Wraight, E.P. & Hodges, J.R. (1993). Neuropsychological and SPECT findings during and after transient global amnesia: Evidence for the differential impairment of remote episodic memory. Journal of Neurology, Neurosurgery and Psychiatry, 56, 1227-1230.
5.17. Gray, J.M., ROBERTSON, I., Pentland, B. & Anderson, S. (1992). Microcomputer-based attentional retraining after brain damage: A randomised group controlled trial. Neuropsychological Rehabilitation, 2, 97-115.
5.18. Halligan, P., ROBERTSON, I.H., Pizzamiglio, L., Homberg, V., Weber, E. & Bergego, C. (1991). The laterality of visual neglect after right brain damage. Neuropsychological Rehabilitation, 1, 281-301.
5.19. Hartman, A., Pickering, R.M. & WILSON, B.A. (1992). Is there a central executive deficit after severe head injury? Clinical Rehabilitation, 6, 133-140.
5.20. Horn, S., SHIEL, A., McLellan, L., Campbell, M., Watson, M. & WILSON, B. (1993). A review of behavioural assessment scales for monitoring recovery in and after coma with pilot data on a new scale of visual awareness. Neuropsychological Rehabilitation, 3, 121-137.
5.21. Horn, S., Watson, M., WILSON, B.A. & McLellan, D.L. (1992). The development of new techniques in the assessment and monitoring of recovery from severe head injury: A preliminary report and case study. Brain Injury, 6, 321-325.
5.22. Kapur, N., Barker, S., Burrows, E. et al., WILSON, B.A. & Loates, M. (in press). Herpes Simplex Encephalitis: Long-term MRI and neuropsychological profile. Journal of Neurology, Neurosurgery and Psychiatry.
5.23. McDowell, I., Anderson, S., Wilson, C., Pentland, B. & ROBERTSON, I. (in press). Late rehabilitation for closed head injury: Clinical psychologists' interventions. Clinical Rehabilitation.
5.24. PATTERSON, K. & WILSON, B. (1990). A ROSE is a ROSE or a NOSE: A deficit in initial letter identification. Cognitive Neuropsychology, 7, (5/6), 447-477.
5.25. Pizzamiglio, L., Bergego, C., Halligan, P., Homberg, V., ROBERTSON, I., Weber, E., WILSON, B., Zoccolotti, P. & Deloche, G. (1992). Factors affecting the clinical measurement of visuo-spatial neglect. Behavioural Neurology, 5, 233-240.
5.26. Riccio, M., Pugh, K., Jadresic, D., Burgess, A., Thompson, C., WILSON, B., Lovett, E., Baldeweg, T., Hawkins, D.A. & Catalan, J. (1993). Neuropsychiatric aspects of HIV-1 infection in gay men: Controlled investigation of psychiatric, neuropsychological and neurological status. Journal of Psychosomatic Research, 37, 819-830.
5.27. Riccio, M., Thompson, C., WILSON, B.A., Morgan, D.J.R. & Lant, A.F. (1992). Neuropsychological and psychiatric abnormalities in myalgic encephalomyelitis: A preliminary report. British Journal of Clinical Psychology, 31, 111-120.
5.28. ROBERTSON, I.H. (1991). Use of left vs right hand in responding to lateralized stimuli in unilateral neglect. Neuropsychologia, 29, 1129-1135.
5.29. ROBERTSON, I.H. (1993). Cognitive rehabilitation in neurologic disease. Current Opinion in Neurology, 6, 756-760.
5.30. ROBERTSON, I.H. (1994). Methodology in Neuropsychological Rehabilitation research. Neuropsychological Rehabilitation, 4, 1-6.
5.31. ROBERTSON, I.H. (1994). Randomised controlled trials and single-instance experiments. Physiotherapy, 80, p. 339.
5.32. ROBERTSON, I.H. (in press). Persisting unilateral neglect: Compensatory processes within multiple interacting circuits. Neuropsychological Rehabilitation.
5.33. ROBERTSON, I.H. & Cashman, L. (1991). Auditory feedback for walking difficulties in a case of unilateral neglect: A pilot study. Neuropsychological Rehabilitation, 1, 175-183.
5.34. ROBERTSON, I.H. & Frasca, R. (1992). Attentional load and visual neglect. International Journal of Neuroscience, 62, 45-56.
5.35. ROBERTSON, I.H., Halligan, P.W., Bergego, C., Homberg, V., Pizzamiglio, L., Weber, E. & WILSON, B.A. (1994). Right neglect following right brain damage. Cortex, 30, 199-214.
5.36. ROBERTSON, I.H. & North, N. (1992). Spatio-motor cueing in unilateral left neglect: The role of hemispace, hand and motor activation. Neuropsychologia, 30, 553-563.
5.37. ROBERTSON, I.H. & North, N. (1993). Active and passive activation of left limbs: Influence on visual and sensory neglect. Neuropsychologia, 31, 293-300.
5.38. ROBERTSON, I.H. & North, N. (1993). Fatigue versus disengagement in unilateral neglect. Journal of Neurology, Neurosurgery and Psychiatry, 56, 717-719.
5.39. ROBERTSON, I.H. & North, N. (1994). One hand is better than two: Motor extinction of left hand advantage in unilateral neglect. Neuropsychologia, 32, 1-11.
5.40. ROBERTSON, I.H., North, N. & Geggie, C. (1992). Spatiomotor cueing in unilateral left neglect: Three case studies of its therapeutic effects. Journal of Neurology, Neurosurgery and Psychiatry, 55, 799-805.
5.41. ROBERTSON, I.H., Tegnèr, R., Goodrich, S. & Wilson, C. (in press). Walking trajectory and hand movements in unilateral left neglect: A vestibular hypothesis. Neuropsychologia.
5.42. SHIEL, A. & WILSON, B.A. (1992). Performance of stroke patients on the Middlesex Elderly Assessment of Mental State. Clinical Rehabilitation, 6, 283-289.
5.43. SHIEL, A., WILSON, B., Horn, S., Watson, M. & McLellan, L. (1993). Can patients in coma following traumatic head injury learn simple tasks? Neuropsychological Rehabilitation, 3, 161-175.
5.44. WILSON, B.A. (1991). Long term prognosis of patients with severe memory disorders. Neuropsychological Rehabilitation, 1, 117-134.
5.45. WILSON, B.A. (1991). Theory, assessment, and treatment in Neuropsychological Rehabilitation. Neuropsychology, 5, 281-291.
5.46. WILSON, B.A. (1992). Recovery and compensatory strategies in head injured memory impaired people several years after insult. Journal of Neurology, Neurosurgery, and Psychiatry, 55, 177-180.
5.47. WILSON, B.A. (1993). Ecological validity of neuropsychological assessment: Do neuropsychological indexes predict performance in everyday activities? Applied and Preventive Psychology, 2, 209-216.
5.48. WILSON, B.A. (1993). Editorial: How do we know that rehabilitation works? Neuropsychological Rehabilitation, 3, 1-4.
5.49. WILSON, B.A. (1994). Syndromes of acquired dyslexia: A 6- to 10-year follow-up study of seven brain-injured people. Journal of Clinical and Experimental Neuropsychology, 16, 354-371.
5.50. WILSON, B.A. & BADDELEY, A.D. (1993). Spontaneous recovery of impaired memory span: Does comprehension recover? Cortex, 29, 153-159.
5.51. WILSON, B.A., BADDELEY, A.D., EVANS, J. & SHIEL, A. (in press). Errorless learning in the rehabilitation of memory impaired people. Neuropsychological Rehabilitation.
5.52. WILSON, B.A., BADDELEY, A.D., SHIEL, A. & Patton, G. (1992). How does post-traumatic amnesia differ from the amnesic syndrome and from chronic memory impairment? Neuropsychological Rehabilitation, 2, 231-243.
5.53. WILSON, B.A. & Davidoff, J. (1993). Partial recovery from visual object agnosia: A 10 year follow-up study. Cortex, 29, 529-542.
5.54. WILSON, B.A. & IVANI-CHALIAN, R. (in press). Performance of Downs Syndrome adults on the children's version of the Rivermead Behavioural Memory Test. British Journal of Clinical Psychology.
5.55. WILSON, B.A., IVANI-CHALIAN, R., Besag, F.M.C. & Bryant, T. (1993). Adapting the Rivermead Behavioural Memory Test for use with children aged 5-10 years. Journal of Clinical and Experimental Neuropsychology, 15, 474-486.
5.56. WILSON, B.A. & PATTERSON, K. (1990). Rehabilitation for cognitive impairment: Does cognitive psychology apply? Applied Cognitive Psychology, 4, 247-260.
5.57. Wilson, C. & ROBERTSON, I.H. (1992). A home-based intervention for attentional slips during reading following head injury: A single case study. Neuropsychological Rehabilitation, 2, 193-205.
5.58. YOUNG, A.W., ROBERTSON, I.H., Hellawell, D.J., de Pauw, K.W. and Pentland, B. (1992). Cotard delusion after head injury. Psychological Medicine, 22, 799-804.
Submitted
5.59. ROBERTSON, I.H., Tegnèr, R., Tham, K., Lo, A. & NIMMO-SMITH, I. Sustained attention training for unilateral neglect: theoretical and rehabilitation implications. (Manuscript submitted to Journal of Clinical and Experimental Neuropsychology).
5.60. WILSON, B.A. Semantic memory impairments following non-progressive brain damage. (Manuscript submitted to Memory)
Invited Chapters and Commentaries
5.61. D'Erme, P., Gainotti, G., Bartolomeo, P. & ROBERTSON, I. (1994). Early ipsilateral orienting of attention in patients with contralateral neglect. In M.J. Riddoch & G.W. Humphreys (Eds.), Cognitive Neuropsychology and Cognitive Rehabilitation (pp. 205-223). Hove: Lawrence Erlbaum Associates.
5.62. Halligan, P., ROBERTSON, I., Pizzamiglio, L., Hömberg, V., Weber, E. & Bergego, C. (1993). The assessment and classification of visual inattention after right hemisphere damage. In F.J. Stachowiak, R. De Bleser, G. Deloche, R. Kaschel, H. Kremin, P. North, L. Pizzamiglio, I. Robertson, & B. Wilson, (Eds.), Developments in the Assessment and Rehabilitation of Brain-damaged Patients: Perspectives from a European Concerted Action (pp. 73-78). Tübingen: Gunter Narr Verlag.
5.63. Marshall, J.C., Halligan, P.W. & ROBERTSON, I.H. (1993). Contemporary theories of unilateral neglect: A critical review. In I.H. Robertson & J.C. Marshall (Eds.), Unilateral Neglect: Clinical and Experimental Studies (pp. 311-329). Hove, Sussex: Lawrence Erlbaum Associates.
5.64. Pizzamiglio, L., Bergego, C., Halligan, P., Hömberg, V., ROBERTSON, I., Weber, E., WILSON, B., Zoccolotti, P. & Deloche, G. (1993). Factors affecting the clinical measurement of visuo-spatial neglect. In F.J. Stachowiak, R. De Bleser, G. Deloche, R. Kaschel, H. Kremin, P. North, L. Pizzamiglio, I. Robertson, & B. Wilson, (Eds.), Developments in the Assessment and Rehabilitation of Brain-damaged Patients: Perspectives from a European Concerted Action (pp. 59-72). Tübingen: Gunter Narr Verlag.
5.65. ROBERTSON, I.H. (1993). The rehabilitation of visuo-spatial, visuo-perceptual and apraxic disorders. In R.J. Greenwood, M.P. Barnes, T.M. McMillan & C.D. Ward (Eds.), Neurological Rehabilitation (pp. 179-188). Edinburgh: Churchill Livingston.
5.66. ROBERTSON, I.H. (1993). The relationship between lateralised and non-lateralised attentional deficits in unilateral neglect. In I.H. Robertson & J.C. Marshall (Eds.), Unilateral Neglect: Clinical and Experimental Studies (pp. 257-275). Hove, Sussex: Lawrence Erlbaum Associates.
5.67. ROBERTSON, I.H. (1994). The rehabilitation of attentional and hemi-inattentional disorders. In M.J. Riddock & G.W. Humphreys (Eds.), Cognitive Neuropsychology and Cognitive Rehabilitation (pp. 173-186). Hove: Lawrence Erlbaum Associates.
5.68. ROBERTSON, I.H. (in press). Neuropsychology: Recovery after brain lesions. In M. Swash & Wilden (Eds.), Outcome of Neurological and Neurosurgical Disorders. Cambridge: Cambridge University Press.
5.69. ROBERTSON, I., Bergego, C., Halligan, P., Hömberg, V., Pizzamiglio, L., Weber, E. & WILSON, B. (1993). Why do people with unilateral left neglect sometimes neglect to the right? In F.J. Stachowiak, R. De Bleser, G. Deloche, R. Kaschel, H. Kremin, P. North, L. Pizzamiglio, I. Robertson, & B. Wilson, (Eds.), Developments in the Assessment and Rehabilitation of Brain-damaged Patients: Perspectives from a European Concerted Action (pp. 79-84). Tübingen: Gunter Narr Verlag.
5.70. ROBERTSON, I. & Halligan, P. (1993). Introduction to unilateral neglect. In F.J. Stachowiak, R. De Bleser, G. Deloche, R. Kaschel, H. Kremin, P. North, L. Pizzamiglio, I. Robertson, & B. Wilson, (Eds.), Developments in the Assessment and Rehabilitation of Brain-damaged Patients: Perspectives from a European Concerted Action (pp. 55-57). Tübingen: Gunter Narr Verlag.
5.71. ROBERTSON, I.H., Halligan, P.W. & Marshall, J.C. (1993). Prospects for the rehabilitation of unilateral neglect. In I.H. Robertson & J.C. Marshall (Eds.), Unilateral Neglect: Clinical and Experimental Studies (pp. 279-292). Hove, Sussex: Lawrence Erlbaum Associates.
5.72. Skilbeck, C. & ROBERTSON, I.H. (1992). Computer-assistance in the management of memory and cognitive impairment. In B.A. Wilson & N. Moffat (Eds.), Clinical Management of Memory Problems (Second edition) (pp. 155-188). London: Chapman & Hall.
5.73. WILSON, B.A. (1992). Memory therapy in practice. In B.A. Wilson & N. Moffat (Eds.), Clinical Management of Memory Problems (2nd edition) (pp. 120-153). London: Chapman & Hall.
5.74. WILSON, B.A. (1992). Rehabilitation and memory disorders. In L.R. Squire & N. Butters (Eds.), Neuropsychology of Memory (Second edition) (pp. 315-321). New York: The Guilford Press.
5.75. WILSON, B.A. (1992). Single-case experimental designs in Neuropsychological Rehabilitation. In B.P. Rourke, L. Costa, D. Cicchetti, K.M. Adams & K.J. Plasterk (Eds.), Methodological and Biostatistical Foundations of Clinical Neuropsychology (pp. 112-130). Lisse, Amsterdam: Swets & Zeitlinger. [Reprinted from 1987]
5.76. WILSON, B.A. (1993). Coping with memory impairment. In G.M. Davies & R.H. Logie (Eds.), Memory in Everyday Life (pp. 461-481). Amsterdam: Elsevier Science Publishers, B.V.
5.77. WILSON, B.A. (1993). Recent developments in the assessment of memory. In F.J. Stachowiak, R. De Bleser, G. Deloche, R. Kaschel, H. Kremin, P. North, L. Pizzamiglio, I. Robertson, & B. Wilson, (Eds.), Developments in the Assessment and Rehabilitation of Brain-Damaged Patients: Perspectives from a European Concerted Action (pp. 99-105). Tübingen: Gunter Narr Verlag.
5.78. WILSON, B.A. (in press). La riabilitazione dei disturbi della memoria. In A. Mazzucci (Ed.), La Riabilitazione Neuropsicologia (Second edition). Bologna: Societa editrice il Mulino.
5.79. WILSON, B.A. (in press). Management and remediation of memory problems in brain damaged adults. In A.D. Baddeley, B.A. Wilson & F. Watts (Eds.), Handbook of Memory Disorders. Chichester: John Wiley & Sons.
5.80. WILSON, B.A. (in press). Memory rehabilitation: Compensation for memory problems. In L. Bäckman & R. Dixon (Eds.), Psychological Compensation. Hillsdale, N.J.: Lawrence Erlbaum Associates.
5.81. WILSON, B.A. (in press). The ecological validity of neuropsychological assessment of traumatically brain injured patients. In R.J. Sbordone (Ed.), The Ecological Validity of Neuropsychological Testing. Paul M Deutsch Press.
5.82. WILSON, B.A. & Moffat, N. (1992). The development of group memory therapy. In B.A. Wilson & N. Moffat (Eds.), Clinical Management of Memory Problems (2nd edition) (pp. 242-273). London: Chapman & Hall.
5.83. WILSON, B.A. & Wearing, D. (in press). Prisoner of consciousness: A permanent state of just awakening. In R. Campbell & M. Conway (Eds.), Broken Memories: Neuropsychological Case Studies. Oxford: Blackwell.
5.84. WILSON, B.A., SHIEL, A., Watson, M., Horn, S. & McLellan, D.L. (in press). Monitoring behaviour during coma and post-traumatic amnesia. In B. Uzzell & A-L. Christensen (Eds.), Progress in the Rehabilitation of Brain-Injured People. Boston: Kluwer Academic Publishers.
Tests and Patents
5.85. Kopelman, M., WILSON, B. & BADDELEY, A.D. (1990). The Autobiographical Memory Interview. Thames Valley Test Company.
5.86. ROBERTSON, I.H., WARD, T. & RIDGEWAY, V. (in press). The Test of Everyday Attention. Flempton: Thames Valley Test Company.
5.87. WILSON, B.A., IVANI-CHALIAN, R. & Aldrich, F. (1991). The Rivermead Behavioural Memory Test for Children aged 5-10 years. Bury St Edmunds: Thames Valley Test Company.
Dissemination
5.88. Halligan, P. & ROBERTSON, I.H. (1992). The assessment of unilateral neglect. In J. Crawford, W. McKinlay & D. Parker (Eds.), Principles and Practice of Neuropsychological Assessment (pp. 151-175). Lawrence Erlbaum Associates.
5.89. Powell, G.E. & WILSON, B.A. (in press). Investigation of neurological problems. In S.J.E. Lindsay & G.E. Powell (Eds.), A Handbook of Clinical Adult Psychology, Second edition. Aldershot: Gower Press.
5.90. Vincent, C. & ROBERTSON, I.H. (1993). Recovering from a medical accident: The consequences for patients and their families. In C. Vincent, M. Ennis & R. Audley (Eds.), Medical Accidents (pp. 150-166). Oxford: Oxford University Press.
5.91. WILSON, B.A. (1992). Assessment and management of memory problems. In N. von Steinbüchel, D.Y. von Cramon & E. Pöppel (Eds.), Neuropsychological Rehabilitation (pp. 195-202). Berlin: Springer-Verlag.
5.92. WILSON, B.A. (in press). Cognitive Problems Following a Stroke. London: Chest, Heart and Stroke Association.
5.93. WILSON, B.A. (in press). Neuropsychological Rehabilitation. In J.G. Beaumont & J. Sergeant (Eds.), The Blackwell Dictionary of Neuropsychology. Oxford: Blackwell.
5.94. WILSON, B.A. (in press). Research and evaluation in rehabilitation. In D.L. McLellan & B.A. Wilson (Eds), The Handbook of Rehabilitation Studies. Cambridge: Cambridge University Press.
5.95. WILSON, B.A. (in press). The management of acquired cognitive disorders. In D.L. McLellan & B.A. Wilson (Eds.), The Handbook of Rehabilitation Studies. Cambridge: Cambridge University Press.
5.96. WILSON, B.A. & Powell, G.E. (in press). Neurological problems: Treatment and rehabilitation. In S. Lindsay & G.E. Powell (Eds.), A Handbook of Clinical Adult Psychology (Second edition). Aldershot: Gower Press.
5.97. WILSON, B.A. & ROBERTSON, I.H. (1992). Editorial. Neuropsychological Rehabilitation, 2, 1-2.
5.98. WILSON, B.A. & Staples, D. (1992). Working with people with physical handicap. In J. Marzillier & J. Hall (Eds.), What is Clinical Psychology? (2nd edition) (pp. 142-198). Oxford: Oxford University Press.
REFERENCES TO OTHER WORK
BADDELEY, A.D. & Hitch, G. (1974). Working memory. In G.H. Bower (Ed.), The Psychology of Learning and Motivation, vol. 8 (pp. 47-89). New York: Academic Press.
Levin, H.S., Grossman, R.G., Rose, J.E. & Teasdale, G. Long term neuropsychological outcome of closed head injury. Journal of Neurosurgery, 50, 412-422, 1979.
SHALLICE, T. (1982). Specific impairments of planning. Philosophical Transactions of the Royal Society London B, 298, 199-209.
Shores, E.A., Marosszeky, J.E., Sandanam, J. & Batchelor, J. (1986). Preliminary validation of a clinical scale for measuring the duration of post-traumatic amnesia. The Medical Journal of Australia, 144, 596-572.
Snowden, J., Griffiths, H. & Neary, D. (in press). Semantic dementia: Autobiographical contribution to preservation of meaning. Cognitive Neuropsychology.
WILSON, B.A., Cockburn, J. & BADDELEY, A.D. (1985). The Rivermead Behavioural Memory Test. Bury St Edmunds: Thames Valley Test Company.
Grant: From the Medical Research Council (joint holder): £104,000 (Grant No. SPG 8175555) for development of assessment procedures for use with patients surviving severe head injury. (B.A. Wilson, D.L. McLellan & M.J. Campbell) (3 years)
Collaborations
Robertson
UK based
McMillan - Wolfson Rehabilitation Center, London
Wilson - Astley Ainslie Hospital, Edinburgh
Hodges - Neurology, Cambridge
O'Connel - Stroke Research Unit, Gateshead
Halligan - Neurology, Oxford
Marshall - Neurology, Oxford
Lo - Rehabilitation, Southampton
North - Psychology, Odstock Hospital, Salisbury
Outside UK
Tegnèr - Neurology, Karolinska Institute, Stockholm
Pizzamiglio - Psychology, Rome
Nico - Psychology, Rome
Gainotti - Neurology, Rome
D'Erme - Neurology, Rome
Wilson
UK based
Alderman - Clinical Psychology, St. Andrews Hospital, Northampton
Burgess - Psychology, University College London
Carr - Psychology, St. George's Hospital, London
Cockburn - Rivermead Rehabilitation Centre, Oxford
Della Sala - Psychology, Aberdeen
Green - Psychiatry, St. Thomas's Hospital, London
Hodges - Neurology, Cambridge
Huppert - Psychiatry - Cambridge
Kapur - Wessex Neurological Centre, Southampton
Kopelman - Psychiatry, St. Thomas's Hospital, London
McKenna - Psychiatry, Cambridge
McLellan, Shiel, Ward - Rehabilitation, Southampton
Pickard - Neurosurgery, Cambridge
Outside UK
Chiapello, Kime, Prigatano - Barron Neurological Institute, Phoenix
Hersh, Treadgold - Interactive Proactive Mnemonic Systems, San Jose