Key messages
- For people with mild-to-moderate dementia, cognitive stimulation probably leads to small benefits in cognition (the general ability to think and remember).
- We found a range of other probable benefits, including improved well-being, mood and day-to-day abilities, but benefits were generally slight and, especially for cognition and well-being, varied greatly between studies.
- Most studies evaluated group cognitive stimulation. Future studies should try to clarify the effects of individual cognitive stimulation, assess how often group sessions should take place to have the best effect, and identify who benefits most from cognitive stimulation.
What is dementia?
Dementia is an umbrella term for numerous brain disorders. Alzheimer’s disease is the most common of these. People of all ages can develop dementia, but most often it occurs in later life. People with dementia typically experience a decline in their cognitive abilities, which can impair memory, thinking, language and practical skills. These problems usually worsen over time and can lead to isolation, upset and distress for the person with dementia and those providing care and support.
Cognitive stimulation
Cognitive stimulation (CS) is a form of 'mental exercise' developed specifically to help people with dementia. It involves a wide range of activities aiming to stimulate thinking and memory generally, including discussion of past and present events and topics of interest, word games, puzzles, music and creative practical activities. Usually delivered by trained staff working with a small group of people with dementia for around 45 minutes twice-weekly, it can also be provided on a one-to-one basis. Some programmes have trained family carers to provide CS to their relative.
What did we want to find out?
We wanted to find out if CS was better for people living with dementia than usual care or unstructured social activities to improve:
- cognitive abilities (including memory, thinking and language skills)
- well-being and mood
- day-to-day abilities
- distress and upset for the person with dementia and/or carers
We also wanted to find out if family carers experienced any changes associated with the person with dementia receiving CS or if there were any unwanted effects.
What did we do?
We searched for studies that looked at group or individual CS compared with usual care or unstructured social activity in people living with dementia.
We compared and summarised the results of the studies and rated our confidence in the evidence, based on factors such as study methods and sizes.
What did we find?
We found 37 studies involving 2766 participants with mild or moderate dementia and an average age of 79 years. The biggest study involved 356 participants, the smallest 13. The studies were conducted in 17 countries from five continents, with most in Europe. Fewer than half (16) included participants living in care homes or hospitals. The length of the trials varied from four weeks to two years. Sessions per week varied from one to six. The overall number of sessions varied from eight to 520. Most studies lasted for around 10 weeks, with around 20 sessions. Most studies offered CS in groups, with just eight examining individual CS.
Main results
No negative effects were reported. We found that CS probably results in a small benefit to cognition at the end of the course of sessions compared with usual care/unstructured activities. This benefit equates roughly to a six-month delay in the cognitive decline usually expected in mild-to-moderate dementia. We found preliminary evidence suggesting that cognition benefited more when group sessions occurred twice weekly or more (rather than once weekly) and that benefits were greater in studies where participants’ dementia at the outset was of mild severity.
We also found that participants improved on measures of communication and social interaction and showed slight benefits in day-to-day activities and in their own ratings of their mood. There is probably also a slight improvement in participants’ well-being and in experiences that are upsetting and distressing for people with dementia and carers. We found CS probably made little or no difference to carers' mood or anxiety.
What are the limitations of the evidence?
Our confidence in the evidence is only moderate because of concerns about differences in results between studies. We cannot be certain of the exact reasons for these differences, but we noted that studies varied in:
• the way CS was delivered (individually, in groups, using an app) and the programme of activities included
• who delivered the programme (trained professionals, care workers, family carers)
• the frequency of sessions (1 per week to 5 per week)
• the duration of the programme (from 4 weeks to 1 or 2 years)
• the type(s) of dementia with which participants were diagnosed and the severity of the dementia
• whether participants lived in care homes and hospitals or in their own homes
We were unable to examine as many of these sources of potential difference as would have been desirable because of the relatively small number of studies reflecting each aspect.
How up-to-date is this evidence?
This review updates our previous review from 2012, with evidence up-to-date to March 2022.