SAN DIEGO—Patients with multiple sclerosis (MS) and cognitive impairment may benefit from increasing their cognitive reserve and from rehabilitation techniques such as self-generated learning, spaced learning, and spaced retrieval, researchers reported at the Fourth Cooperative Meeting of the Consortium of MS Centers and Americas Committee for Treatment and Research in MS.
Approximately two-thirds of patients with MS have cognitive impairment, and patients cite cognition as a critically important issue, said John DeLuca, PhD, Vice President for Research at the Kessler Foundation Research Center in West Orange, New Jersey, and Professor of Physical Medicine and Rehabilitation and Neurology and Neuroscience at the University of Medicine and Dentistry of New Jersey–New Jersey Medical School in Newark. “It’s something we should be paying a lot more attention to in MS clinics throughout the country,” he told Neurology Reviews.
According to Dr. DeLuca, rehabilitation techniques are most effective when preceded by an accurate assessment of a patient’s impairment, but many impairment assessments rely on self-report. “The accuracy of self-reported cognitive problems can be a significant issue,” he said. “You cannot treat a cognitive problem unless you know what it is.”
To further explore this issue, he and his colleagues ran a series of studies examining “actual reality,” a technique that measures actual everyday life activity, in this case using an Internet task in which people were asked to book an airline ticket to Florida. “This is an actual behavior. You can do it at home or in the lab, in New York City, or in China,” said Dr. DeLuca.
The investigators examined whether the actual performance of healthy controls and patients with MS correlated with self-reports and with performance on cognitive tasks. Results showed that self-report did not correlate with actual performance of an actual task in everyday life, but objective memory and composite scores of cognition predicted actual, everyday life performance. Dr. DeLuca believes more formalized assessment of cognitive problems is necessary to devise appropriate treatment plans that can improve everyday life functional activity.
Learning and Memory
Treatment is also enhanced by accurately assessing the cause of memory problems in patients with MS. “People always talk about persons with MS having a memory problem. Well, there is no memory without learning. If you don’t learn something, you can’t remember it,” said Dr. DeLuca.
After studying memory and learning problems in patients with MS, he and his colleagues found that the patients had difficulty with the learning of new information but were able to accurately retrieve newly learned information. That is, the major problem is not in retrieval from long-term storage, but in difficulty in the acquisition of new knowledge. “It wasn’t so much a memory problem—it was a learning problem,” he stated. “Our treatment should be, let’s make sure they learn to begin with.”
Several techniques might address acquisition issues, including one approach called self-generated learning. Research has shown that patients who generate their own answers to questions remember information better than those who are simply presented with material. “Self-generating provides stronger encoding, which makes it easier to retrieve the information,” Dr. DeLuca explained.
Spaced learning also benefits patients with MS. Dr. DeLuca cited a study in which participants studied a newspaper article three times in a row versus three times that were spaced apart. The patients remembered significantly more information when the learning trials were spaced apart, he noted.
Furthermore, research has shown that individuals improve retrieval of information by studying material on one trial and then being tested on a second trial, rather than studying the information twice. This finding—known as spaced retrieval or the testing effect—is counterintuitive, as most people would opt to study material several times. However, the act of testing increases the strength of the encoding of information, which makes it easier to retrieve.
When cognitive techniques such as spaced retrieval, self-generation, and spaced learning are used in conjunction with one another, they can significantly improve learning in patients with MS. “We found that if you made sure that people learned, their recall and recognition—their retrieval from long-term storage—was as good as that of healthy individuals,” said Dr. DeLuca.
Researchers have sought to explain why some patients with MS show little or no cognitive impairment, while others with the same degree of MRI disease progression show significant cognitive impairment. The cognitive reserve hypothesis might explain this disparity, said Dr. DeLuca, as well as provide an avenue for cognitive rehabilitation. According to the hypothesis, individuals who lead an intellectually stimulating life may develop greater cerebral efficiency, which, in turn, provides protection from MS disease expression (ie, cognitive impairment).
Dr. DeLuca added that patients with MS who have low cognitive reserve show greater impairment in cognition than those with high cognitive reserve, despite displaying similar levels of brain atrophy on MRI. “People who develop a brain that’s more resistant to the expression of MS will be much less likely to show these cognitive problems,” he said.
This finding has significant implications for the cognitive rehabilitation of patients with MS. Patients might build cognitive reserve through intellectual hobbies such as reading, art, and music, as well as by engaging in aerobic exercise.
For a young person diagnosed with MS, “building a cognitive reserve is going to be the very backbone of cognitive rehabilitation,” said Dr. DeLuca. “It may not be protective against disease progression, but it could be protective against the expression of the disease.”
Dr. DeLuca emphasized that cognitive rehabilitation influences the family life, employment, social relationships, and everyday life of patients. “Cognitive interventions can have a profound effect on the life of persons with MS, and that’s something we really need to focus on,” he concluded.
Click here to listen to an accompanying audio interview.
Chiaravalloti, ND, DeLuca, J. Cognitive impairment in multiple sclerosis. Lancet Neurology. 2008;7(12):1139-1151.
Sumowski JF, Chiaravalloti N, Leavitt VM, et al. Cognitive reserve in secondary progressive multiple sclerosis. Mult Scler. 2012 Mar 2 [Epub ahead of print].