A review of 15 randomized controlled trials in which people with mild to moderate dementia were offered mental stimulation has concluded that such stimulation does indeed help slow down cognitive decline.

In total, 718 people with mild to moderate dementia, of whom 407 received cognitive stimulation, were included in the meta-analysis. The studies included in the review were identified from a search of the Cochrane Dementia and Cognitive Improvement Group Specialized Register, and included all randomized controlled trials of cognitive stimulation for dementia which incorporated a measure of cognitive change.

Participants were generally treated in small groups and activities ranged from discussions and word games to music and baking. Treatment was compared to those seen without treatment, with "standard treatments" (such as medicine, day care or visits from community mental health workers), or with alternative activities such as watching TV and physical therapy.

There was a “clear, consistent benefit” on cognitive function for those receiving cognitive stimulation, and these benefits were still seen one to three months after the treatment. Benefits were also seen for social interaction, communication and quality of life and well-being.

While no evidence was found for improvements in the mood of participants, or their ability to care for themselves or function independently, or in problem behaviors, this is not to say that lengthier or more frequent interventions might not be beneficial in these areas (that’s purely my own suggestion).

In one study, family members were trained to deliver cognitive stimulation on a one-to-one basis, and the reviewers suggested that this was an approach deserving of further attention.

The reviewers did note that the quality of the studies was variable, with small sample sizes. It should also be noted that this review builds on an earlier review, involving a subset of these studies, in which the opposite conclusion was drawn — that is, at that time, there was insufficient evidence that such interventions helped people with dementia. There is no doubt that larger and lengthier trials are needed, but these new results are very promising.