The first published (case) studies of cognitive rehabilitation for people with acquired brain injury appeared 28 years ago. In the ensuing decade, the clinical practice of cognitive rehabilitation has expanded and became a common component of neurological rehabilitation, despite the perception that the effectiveness of this form of intervention remains unproven. The empirical basis for cognitive rehabilitation has continued to grow, allowing for multiple attempts to synthesize and evaluate this literature through “evidence-based” reviews, particularly within the past five years.
In the United States, systematic reviews of cognitive rehabilitation have been conducted through the American Congress of Rehabilitation Medicine (ACRM) (Cicerone et al., 2000; 2005) and the Academy of Neurogenic Communication Disorders and Sciences (Sohlberg et al., 2003). Efforts to evaluate the effectiveness of treatments for cognitive rehabilitation in Europe have been conducted through the Cochrane Collaboration (Lincoln et al, 2003; Majid et al., 2003).
The Cochrane reviews have typically relied on stringent criteria for accepting the scientific evidence, often producing a dearth of clinically relevant recommendations. In 1999, a Task Force on Cognitive Rehabilitation was established under the auspices of the European Federation of Neurologic Societies (EFNS).
The explicit aim of the Task Force was the evaluation of existing evidence for the clinical effectiveness of cognitive rehabilitation in stroke and traumatic brain injury (TBI) and the production of recommendations for neurological practice. Guidelines proposed by the EFNS were first published in 2003 (Cappa et al., 2003), and shared many of the methods and conclusions of the initial ACRM review. More recently, the EFNS has published an update and revision of its previous work (Cappa et al., 2005).
The EFNS has followed the strategy of evaluating interventions according to discrete types of deficits after TBI and stroke, allowing for specific recommendations for different forms of intervention. The original EFNS paper reviewed interventions for aphasia, unilateral neglect, attention, memory, apraxia and acalculia. The current paper extends this approach by delineating and evaluating more specific approaches within several of these areas.
For example, both papers provide strong recommendations for the effectiveness of visual scanning training for unilateral neglect after stroke. The current paper extends these recommendations by suggesting that the incorporation of techniques such as trunk rotation, forced use of the left eye, prism goggles and video feedback are probably effective interventions, and that vestibular stimulation and transcutaneous electrical stimulation of neck muscles are possibly effective, but limited because they produce transient effects.
Within the area of memory remediation, the recent EFNS paper discriminates among compensatory techniques without external memory aids, techniques with non-electronic external memory aids, and the use of assistive electronic technologies for memory remediation.
Although the original EFNS paper concluded that compensatory training for subjects with mild memory impairments was an effective intervention, consistent with earlier reviews (Carney et al., 1999; Cicerone et al., 2000, 2005), the subsequent paper downgrades this intervention as “possibly effective,” noting that it remains unclear to what degree the benefits of compensatory training without memory aids depends on the severity of memory impairment.
The EFNS paper also notes that several less controlled studies support the “possible effectiveness” of non-electronic memory aids such as diary or notebook training (which were included within the ACRM recommendations for compensatory strategy training). The authors of the EFNS paper do note that errorless learning techniques are “probably effective” for the remediation of memory deficits, although this technique received little specific support in the 2005 ACRM update.
It is perhaps of most interest to note that the EFNS paper concludes that electronic memory aids such as computers, paging systems or portable voice recorders have been shown to be effective in several Class III studies and are recommended as “probably effective” for improving the performance of everyday activities for people with TBI or stroke. This is an area that is likely to receive increasing attention, although the studies to date remain limited (Cicerone et al., 2005).
The discrepancies between the most current EFNS and ACRM reviews are likely to reflect the difficulties interpreting studies that are widely heterogeneous with regard to the subject populations (e.g., age, chronicity, type and location of brain damage, severity of impairment) and precise nature of the interventions.
However, the EFNS paper does imply that it should become increasingly possible (and necessary) to develop studies that allow for a comparison of specific, theoretically-based and formally defined interventions within a given area of intervention. These types of controlled comparisons between intervention techniques are largely absent in the literature.
There is one area of intervention that is conspicuous by it absence from the EFNS paper: the effectiveness of multi-disciplinary, comprehensive and holistic approaches to the rehabilitation of people with cognitive limitations after TBI or stroke.
There is increasing evidence from clinical, observational studies that this is an effective form of intervention for people who exhibit multiple areas of cognitive impairment and significant functional and social disability in their daily lives. In contrast, more highly constrained, randomonized trials of comprehensive cognitive rehabilitation have produced more equivocal results, but suffer from methodological limitations that limit the ability to generalize these results to standard clinical practice.
Research in this area is made difficult by numerous factors, including the ability to isolate and define the therapeutic ingredients of these complex interventions and the need to use of a variety of relevant, health-related outcome measures reflecting participants’ social participation and well-being. Since comprehensive, multi-disciplinary rehabilitation is likely to represent the hallmark of clinical practice, the development and critical analysis of well-controlled research in this area will be fundamental to evaluating the effectiveness of cognitive rehabilitation.
Cappa et al. (2005) also note the methodological limitations inherent in the existing body of research, and the limitations that this imposes on the empirical validation of specific interventions. For clinicians, we have not yet reached the stage where it is possible to routinely apply standardized interventions across settings.
However, familiarity with the EFNS paper and other systematic reviews should at least provide an idea of the principles of effective cognitive rehabilitation. The appreciation of these limitations should also help guide researchers in their attempts to conduct well-designed comparisons of alternative interventions, for well-defined target deficits, in specific populations.
I think that we can also look forward to increasing national and international collaboration among the various organization concerned with these issues, in order to reach some consensus on the best practices of cognitive rehabilitation.
Keith D. Cicerone, Ph.D.
Director of Neuropsychology and Rehabilitation Psychology
JFK-Johnson Rehabilitation Insitute, Edison, NJ
Clinical Professor, Department of Physical Medicine and Rehabilitation
Robert Wood Johnson Medical School, UMDNJ, New Brunswick, NJ
- Cappa SF, Benke T, Clarke S, Rossi B, Stemmer B, van Heugten CM. EFNS Guidelines on cognitive rehabilitation: report of an EFNS Task Force. Eur J Neurol, 2003; 10:11-23.
- Cappa SF, Benke T, Clarke S, Rossi B, Stemmer B, van Heugten CM. EFNS Guidelines on cognitive rehabilitation: report of an EFNS Task Force. Eur J Neurol, 2005; 12:665-680.
- Carney N, Chesnut RM, Maynard H, Mann NC, Patterson P, Helfand M. Effect of cognitive rehabilitation on outcomes for persons with traumatic brain injury: A systematic review. J Head Trauma Rehabil.\ 1999; 14:277-307.
- Cicerone KD, Dahlberg C, Kalmar K, Langenbahn DM, Malec JF, Bergquist TF et al. Evidence-based cognitive rehabilitation: recommendations for clinical practice. Arch Phys Med Rehab 2000; 81; 1596-1615.
- Cicerone KD, Dahlberg C, Malec JF, Langenbahn DM, Felicettti T et al. Evidence-based cognitive rehabilitation: Updated review of the literature from 1998 through 2002. Arch Phys Med Rehab 2005; 86; 1681-1692.
- Sohlberg MM, Avery J, Kennedy M, Ylvisaker M, Coelho C, Turkstra L, Yorkston K. Practice guidelines for direct attention training. J Med Speech-Lang Pathol, 2003; 11(3):19-39.
- Lincoln NB, Majid MJ, Weyman N. Cognitive rehabilitation for attention deficits following stroke (Cochrane Review). In the Cochrane Library, 2003, Issue 4. Chicester, UK: Wiley & Sons.
- Majid MJ, Lincoln NB, Weyman N. Cognitive rehabilitation for memory deficits following stroke (Cochrane Review). In the Cochrane Library, 2003, Issue 4. Chicester, UK: Wiley & Sons.