Cognitive Stimulation Technique May Prevent Decline in Healthy Elderly

Susan Jeffrey

Medscape Medical News 2008. © 2008 Medscape

July 10, 2008 — Swiss researchers have developed a computer-based cognitive training technique that appears to significantly increase cognitive performance, specifically working memory, in healthy elderly subjects.

The training tool, dubbed BrainStim by the authors, used by subjects 4 times per week over 4 weeks, was associated with a significant increase in working-memory function over their baseline scores in a small pilot trial.

"In healthy aging people, we could see that with the training, they improved significantly, and this improvement was seen both in neuropsychological testing and in their daily living," first author Iris K. Penner, PhD, from the University of Basel, in Switzerland, told Medscape Neurology & Neurosurgery.

Their results were presented at the 18th Meeting of the European Neurological Society, in Nice, France.

Working Memory the Key

During aging, cognitive decline is a natural process that primarily affects mental speed, short-term memory, and working memory, the authors write. The training model they have developed is based on the work of Baddeley and Hitch, published in 1974, that proposed that working memory is a kind of temporary storage used in everyday life, Dr. Penner explained. "So if, for example, you go to the supermarket, and you would like to remember what to buy, that is stored for a short period in working memory."

This decline is seen not only in healthy aging but in neurodegenerative and inflammatory diseases, including multiple sclerosis, dementia, and schizophrenia, she noted. "We call it a key feature in cognition. If you have a decline there, if there is a problem with working memory, in the future you may have problems in other cognitive domains," Dr. Penner said. "That's why we focus the training on that central function."

There is evidence from several studies, the authors write, that neuroplasticity can be induced by cognitive intervention. In this pilot study, the researchers tested the hypothesis that their cognitive training technique might induce neuroplasticity and improve working-memory function in healthy elderly subjects.

"When we looked in the literature, there was no computer-based training available, and therefore we developed our own," Dr. Penner said. The training tool, called BrainStim, currently consists of 3 modules:

* City map module — In this task, aimed at training spatial orientation, subjects must find their way on a city map, after having been shown the route visually or given verbal instructions that must be recalled.
* Find pairs module — Based on the child's card game Memory, subjects must find matching pairs in an array of cards placed face down, turning 2 cards at each turn. Functions trained by this task include visual object memory and the updating function of the central executive component of working memory.
* Memorize numbers module — In this task, subjects must recall numbers that are given at baseline, then carry out an arithmetic "distractor" task, then reproduce the numbers given at the outset. "If you have 2 numbers, it's easy, but if you have 10 numbers and then a distractor task, your working memory is working very hard to get this information," Dr. Penner notes.

Keep It Simple

In each module, training difficulty is adaptive to the individual, becoming less difficult when performance drops below certain criteria and increasingly difficult when performance exceeds those criteria.

The design is "not that sophisticated," she adds, but they wanted to keep it simple and focus specifically on the working-memory functions, in addition to evaluating the effects scientifically. Based on the Java programming language, it can run on any computer with the Java runtime environment installed. "This is a great advantage compared with most commercial training tools available," they note, including gaming-system-based tools. Those types of programs are more sophisticated from a programming standpoint, she said, but are not targeted specifically for working memory, not have they been evaluated in this way.

In the current pilot study, 9 healthy elderly subjects, 2 female and 7 male, with a mean age of 70 years, took part. All underwent a comprehensive neuropsychological examination, with various subtests examining visual and verbal short-term memory, attention, concentration, and information processing speed, among others.

After baseline, subjects used the training program 4 times per week for 4 weeks, with each training session lasting 45 minutes. After the 16 sessions, testing was repeated.

They found a significant increase in cognitive performance with the training procedure, with a steep increase at the outset followed by a plateauing of the training effect. Statistically, Dr. Penner said, "this could best be described by an exponential function with asymptotic course, meaning that at the beginning you can see most of the training effects and . . . a stability over time is reached."

On the neuropsychological-outcome measures, they found significant changes on several working-memory outcome measures, but only results on the Paced Serial Addition Test (PASAT) showed a significant change in performance after simple learning effects from baseline to posttraining were controlled for. "This test is immune against learning effects but a specific test for higher cognitive functions and working memory, so we could see, independent of learning effects, a specific training effect on working memory," she said.

"The results of our first pilot study indicate that working-memory performance increased after 4 weeks of computerized specific working-memory training," the authors conclude. "In this concern, BrainStim seems to positively influence brain functionality in healthy elderly subjects and might therefore be a useful tool in prevention."

Since completing this pilot study, they have carried out a study in multiple sclerosis patients with similar results, Dr. Penner noted. Currently, they are running a study in patients with schizophrenia.

They are hoping to develop further modules, and there is some interest from a major German bookseller to commercialize the training program, she noted.

Dr. Penner reports no conflict of interest relevant to this presentation.

18th Meeting of the European Neurological Society: Abstract P485. Presented Monday, June 9, 2008.