Effectiveness of Rehabilitation for Cognitive Deficits. P. W. Halligan, D. T. Wade, eds. Oxford: Oxford University Press, 2005. 397 pages, $75.00, softcover: ISBN: 0198526547.
Effectiveness of Rehabilitation for Cognitive Deficits. P. W. Halligan, D. T. Wade, eds. Oxford: Oxford University Press, 2005. 397 pages, $75.00, softcover: ISBN: 0198526547.
This book is based on the proceedings of an invitational, international conference in 2002 that focused on cognitive rehabilitation from several novel perspectives that were both ambitious and important. As is evident from the title, this edited volume is not content to review the efficacy of cognitive rehabilitation-that is, proof that it works on cognition-but claims to be primarily focused on its effectiveness-that is, evidence of the real-world impact of cognitive rehabilitation on the functional consequences of impaired cognition. To this end, authors were apparently instructed not to confine themselves to randomized controlled trials but were encouraged to mine other types of designs such as single-case studies and to use synthetic review methods as well as meta-analyses.
Does this book succeed in presenting evidence for the effectiveness of cognitive rehabilitation? Well, not exactly. Given the state of the science, just about every chapter has to end by saying that "the jury is still out" and "more research is needed." This does not mean that the volume is not useful, because it is, and I recommend it highly for a particular aspect that is not conveyed by the title. Both the conference and the current volume present cognitive rehabilitation within the context of the World Health Organization's International Classification of Function (ICF) framework of pathology, function, activity, participation, and the contextual factors that affect human function. It is laudable to find cognitive rehabilitation thus situated in the larger context of the field, rather than off to the side in an "ivory tower." While there is wide variability among the individual chapters as to how well they deal with this challenge, the volume is more than worthwhile for the attempt. The chapter by Derrick Wade (one of the volume editors) sets the tone, noting that "a cognitive impairment may affect some activities more than others, but does not in itself cause 'cognitive disability,'" and that moreover "the link between specific (cognitive) impairments and specific activities is probably weak."(p37) Taking the broadest possible view, Wade provides valuable models and examples of "cognitive" and other interventions that target the different levels in the ICF, even including the broad domains of personal context (eg, beliefs and attitudes), physical context (eg, environmental cues), and social context (eg, laws and cultures).
The bulk of the volume (16 of the 26 chapters) is addressed to analyzing the effectiveness of cognitive rehabilitation in 4 areas of "well established and common cognitive deficit": attention, memory, language, and executive function. In an unusual and wildly ambitious structure, 4 chapters by different sets of authors are devoted to each of these deficit areas. In each set of 4, the first chapter is charged with presenting the neuroanatomical substrate and major theoretical concepts relevant to the cognitive area; the second chapter focuses on assessment. Following the ICF framework, the third chapter then deals with rehabilitation of the cognitive deficit at the level of impairment and the fourth chapter deals with rehabilitation of the same cognitive deficit at the level of activity/participation. This organization would have been most impressive, had it succeeded; after all, as the science of cognitive rehabilitation advances, it is to be hoped that theory, assessment, and treatment will all be linked, and an implicit goal of this volume is to help create or strengthen these links. But presumably because there was neither an intensive degree of editorial control nor collaboration among the writers in each area, the sets of chapters present quite different conceptualizations of their respective areas, while reviewing much of the same literature. The result is an unfortunate mixture of conceptual incoherence and content overlap within each set of chapters, although some of the individual pieces are extremely well written and comprehensive. In fact, most of the chapters on theoretical models and assessment methods could be lifted from this volume with little impact on the whole, except to focus it on rehabilitation, which might have been more fitting. Notable exceptions include the chapters on memory assessment by Bradley and colleagues and the chapter on executive function theories by Burgess and Simons, both of which draw thoughtful and insightful relationships among their assigned material, and the tasks and goals of rehabilitation in their respective domains.
The chapters on rehabilitation are generally more successful in building on the central theme of the book, although there is some overlap between the 2 chapters in each area addressed to different ICF levels. For example, Jonathan Evans discusses treatments addressing problem-solving and goal-management strategies in his excellent chapter on executive function treatments at the impairment level. This is followed immediately by Andrew Worthington's chapter, which reviews many of the same studies as examples of activity/participation-level interventions. Similar overlap is seen in the 2 chapters on treatments of language deficits. However, the overall effect of this redundancy is more thought-provoking than confusing; inevitably, it means that cognitive interventions are difficult to map cleanly onto the ICF levels used in the wider world of rehabilitation, which is all the more reason why conferences and volumes like this one are needed. It should be noted parenthetically that despite the publication date of 2005, the chapters appear to be inconsistent as to whether or not they were updated following the conference. Seemingly, few of the references in the combined list at the end of the volume carry a date later than 2002. As a result, certain "hot topics" that are being extended to cognitive rehabilitation, such as constraint-based therapy methods, get relatively short shrift.
The volume concludes with 3 chapters on specific diagnoses: traumatic brain injury, stroke, and dementia. The added value of the first 2 is uncertain, as they review many of the same studies already discussed in the chapters on specific cognitive functions. The chapter by Linda Clare on cognitive rehabilitation in early-stage dementia, however, is a valuable resource. Clare provides a clear rationale for intervention and reviews literature that is not covered elsewhere in the book, in discussing treatment with a population that is relatively neglected in rehabilitation.
Several other interesting and provocative chapters contribute to a running theme of the volume: aside from the ICF framework, what is the role of theory in cognitive rehabilitation, and what kinds of theories are necessary and sufficient to advance the field? As she has done in previous writings, Argye Hillis presents clear and reasonable arguments why neither cognitive neuropsychological models nor broad theories of behavior change, such as learning theories, are sufficient for developing cognitive treatments. Ian Robertson discusses ways in which theories of neuronal plasticity underlying behavior change can suggest counterintuitive treatment strategies and prevent well-intended treatments from actually doing harm. Both of these authors make useful comments about our need to know more about natural recovery processes in order for rehabilitation efforts not only to capitalize on them but also to avoid interfering with the brain's natural capacity to heal itself and reorganize its functions.
In summary, Effectiveness of Rehabilitation for Cognitive Deficits is a useful addition to the library of the scientist or practitioner interested in theories and evidence relevant to cognitive rehabilitation. In some ways, the volume is like the field of cognitive rehabilitation itself-messy and thought-provoking, with flashes of brilliance. It is hoped that this work will encourage other efforts to integrate cognitive rehabilitation with the broader field of rehabilitation and to expand the theoretical bases of both.
Tessa Hart, PhD
Institute Scientist, Traumatic Brain Injury Clinical Research Laboratory, Moss Rehabilitation Research Institute, Research Associate Professor, Jefferson Medical College, Elkins Park, Pennsylvania