"This is good news for the industry," said Robert Winningham, a professor at the University of Western Oregon, who was not involved in this study. "This is showing the people who work in memory care communities and nursing homes and assisted living facilities that they can improve cognitive function, and they need to be providing these kinds of interventions."

Cognitive stimulation, as the therapy is called, involves structured activities in a group setting, usually one or more times a week for at least a month.

The sessions might include a discussion of current events, a sort of show-and-tell with objects, baking, drawing or other activities that get the participants to engage their minds.

Bob Woods, a professor at Bangor University in the UK who led the study, said that researchers in this field had considered cognitive stimulation to be helpful for people with dementia, based on earlier work.

To get a better sense of just how much the therapy can do, he and his colleagues at University College London pulled together the findings from 15 studies comparing cognitive stimulation to no extra intervention for people with mild or moderate dementia.

In total, 718 people participated in the studies.

The stimulation sessions lasted from 30 to 90 minutes, and people met as frequently as five times a week. The studies continued for at least a month and up to two years.

"One of the difficulties in dementia is people do become a bit apathetic and withdrawn," Woods told Reuters Health. "So having this structured form of stimulation guarantees they are engaged and active for a period of time."

At the end of the studies people took a test to measure their mental functioning.

Those who were in the cognitive stimulation groups performed about one or two points better than those who didn't participate, on tests that had ranges of zero to 30 and zero to 70.

Woods said the effect is fairly small, but encouraging. He explained that people with dementia typically decline by a few points on these tests in six months or a year.

So a one or two point increase over people who didn't receive any treatment means their dementia, at least in terms of their mental skills, was essentially stabilized and didn't progress.

SOME RESULTS DISAPPOINTING

Other skills for daily living, however, did not show any improvements compared to the people who didn't receive cognitive stimulation.

"To be honest, that's disappointing," Winningham told Reuters Health. "Activities of daily living are your ability to take care of yourself, to do a check book, go grocery shopping. We need to find ways to improve these because that's what will allow people to stay independent and reduce health care costs."

Winningham said the mental gains are important, though, and training staff at assisted living or nursing care facilities to provide cognitive stimulation is a worthwhile investment.

"It's a very inexpensive way to improve cognitive function, relative to much more expensive drug therapies that have been, really, the only thing that we were sure worked before these studies came out," he said.

Woods said most of the studies have focused on interventions given in group sessions, and he'd like to see whether individual sessions, perhaps given by a family member, could deliver similar results.

"I'm quite hopeful some grandchildren would want to do this with their grandfather or grandmother who has dementia," he said.

In the report, published by the Cochrane Collaboration, the authors disclose that some of them have earned money by providing training and manuals for cognitive stimulation.

Cochrane is a large, international network of researchers that consolidates and reviews studies on a given medical treatment.

SOURCE: bit.ly/Af8nyY Cochrane Database of Systematic Reviews, February 2012.

• A Permanent Economic Emergency