One of the most critical and continuing struggles of dementia research is the search for interventions that can reduce the burden of the disease. Despite major progress in the development of drug various therapies, a clinically useful breakthrough in human trials has proven elusive to date. While the search for a pharmacological breakthrough continues, the appeal of non-pharmacological interventions, as an alternative, or in addition to pharmacological therapies is ever increasing.
Cognitive training and cognitive rehabilitation are two such non-pharmacological alternatives. The two approaches often get confused as there is indeed a degree of overlap between them. But there are also important differences: cognitive training aims to bolster a specific cognitive function through the repetitive engagement with carefully designed activities and exercises associated with that ability. This style of intervention assumes that regularly practising tasks related to a given cognitive domain may improve or maintain function in this domain and that benefits may transfer to related functions. On the other hand, cognitive rehabilitation prioritises the identification of individual needs and goals, and the use of techniques and strategies to enable these to be met more easily in the face of decreasing abilities. In this way, cognitive rehabilitation does not focus directly on enhancing cognitive performance but rather aims to improve functioning in personally meaningful day-to-day tasks.
Dr Alex Bahar-Fuchs, from the DCRC – Early Diagnosis and Prevention based at the Australian National University, recently collaborated with researchers in the UK to update the evidence in this emerging research area. Their review was published earlier this month in the prestigious Cochrane Database of Systematic Reviews. The authors examined the current body of evidence for these techniques to evaluate what sort of evidence is currently available and to determine if current research supports the use of these methods.
The authors report that research in related areas has established that both cognitive training and rehabilitation are couched in related yet distinct theoretical traditions. In the case of cognitive training, researchers tend to draw explicitly on theories and empirical findings related to neuroplasticity – a phenomenon which describes the brain's ability to modify existing connections and forge new pathways in the brain. Studies using fMRI have shown changes in patterns of brain activity during memory tasks associated with cognitive training – encouraging because it suggests that improvement in the performance of specific tasks following training reflects changes in brain activity. Clinicians and researchers who practice cognitive rehabilitation on the other hand draw on a variety of evidence-based strategies that have been shown to improve performance on relevant day-to-day tasks. Strategies include taking advantage of relatively intact cognitive skills and systems or by applying strategies that make the most out of residual abilities. Although the application of principles of cognitive rehabilitation is common in other groups of individuals with brain damage – particularly individuals with traumatic brain injury or stroke—adaptation to the field of dementia is relatively recent, in part because it challenges long-held views regarding the purpose of rehabilitation.
The authors found that the current literature does not indicate any benefit or detriment to cognitive training. However, the authors point to several methodological limitations in the cognitive training literature that may be masking the potential benefits of the approach and state that further research is required to definitively ascertain its effects or lack thereof. Unfortunately, the authors were only able to identify one trial of cognitive rehabilitation in mild to moderate dementia. This trial, however, indicated benefits of cognitive rehabilitation in relation to the capacity to perform self-selected meaningful goals and the study design was deemed to be “high quality” by the authors. Ultimately, the authors described the evidence for cognitive rehabilitation to be “tentatively promising” while concluding that at this stage the evidence for cognitive training is insufficient.
A full copy of the review can be accessed via the link below:
Cochrane Database of Systematic Reviews.
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