British researchers have found simple, systematic memory training can help some people with early-stage Alzheimer's disease (AD) to sharpen their memories and reduce disability. This finding points to a possible psychological intervention early in the course of this devastating brain disease, and also lends some urgency to early diagnosis.
In a study published in the October 2002 issue of Neuropsychology, neuropsychologists from the University College London, The Open University, and the Medical Research Council Cognition & Brain Sciences Unit in Cambridge, England, were intrigued by anecdotal "success stories" of memory training provided by rehabilitation experts.
Lead researcher Linda Clare, Ph.D. explained the evidence suggested that even without medicine, "There is a good deal that can be done to improve well-being [in AD]." To assess the validity of such training if standardized, Clare's team conducted a controlled study to see whether it would work with a larger group of people. They also wanted to learn whether the benefits of training endured.
Clare and colleagues examined 12 participants (average age: 71) who were diagnosed with probable Alzheimer's Disease (AD) at the minimal or mild stage, when they still had some capacity for learning. Participants took neuropsychological tests of their general intellectual ability, memory, naming, visuospatial perception, attention and executive function. All of the participants were impaired on at least one of the memory tests, and some also were impaired on naming and perceptual tasks. Researchers also evaluated their mood, behavior, awareness of their memory problems, and the strain on the caregiver (usually the wife or husband) before and after the intervention.
The researchers then trained participants to remember the names of people whom they had difficulty naming in a set of 12 photos that included people in their social network (family and friends) and famous people. They used such memory aids as mnemonic devices, which use the image to jog memory through some kind of meaningful association. These included "vanishing cues," a method in which participants fill in more and more letters in the person's name, until they can recall that name without any help, and "expanding rehearsal," in which people test themselves on what they've learned, in spaced intervals over time. All training minimized the chance of errors, which helped to reduce distress and raise confidence. By training participants' memory for just half of their photo sets, researchers were able to compare memory training with no training, for each participant.
Participants learned the face-name association at the rate of one per week, adding each new pair to their practice until they worked at all six pairs. They continued practicing until a one-month follow-up test of the face-name pairs. Testing was repeated at three, six and 12 months after the end of the post-training baseline trials. The memory training produced a statistically significant improvement in group performance on free recall of trained items. Participants kept their memory gains six months after training, and scores remained above baseline levels after 12 months — even without further practice. These promising results suggest that clinicians may be able to design programs to help people hang on to their memory gains through ongoing new learning. "These methods could be applied very effectively by non-professionals such as friends, volunteers and family members," Clare points out.
The authors speculate that the rehabilitation strategy might have worked by slowly re-establishing links between phonological (name) and semantic (person-specific) representations in the parts of the brain's neocortex, surface areas that deal with language and problem-solving, and are less damaged early in AD than areas known to be the most involved in forming new memories, such as the hippocampus. "This suggests that learning or relearning can take place without involving the hippocampus," says Clare, "albeit perhaps a little slower or less efficient. Although at this point we can only speculate, if other brain areas can take over some of the functions of damaged areas, then this opens up new directions for rehabilitation."
The authors add that because not all participants benefited equally (some didn't improve at all), neuroimaging might reveal the mechanisms involved, as well as why they do or don't respond to training. "In developing any kind of intervention," says Clare, "we need to understand not just whether it is effective, but for whom it is or is not effective. This is especially important in conditions such as AD that affect the brain, because the pattern of strengths and difficulties is not exactly the same for each individual."
In an important secondary finding, people who were more aware of their memory problems were more likely to respond well to memory training. The authors comment that, "Careful assessment of awareness could assist clinicians in determining the suitability of this form of intervention for individual patients."