A group at Bangor University in Wales is comparing reminiscence treatments with more conventional medicines for clinical and cost effectiveness in tackling dementia.
More than 500 people in centres across Wales and England will take part in memory groups in the early part of next year.
Professor Bob Woods, who is leading the research in Bangor, said: "The growing number of people with dementia, and the increasing cost of caring for them, provides a major incentive to develop and test methods of supporting them in the community for longer."
He added: "Drug treatment has received the most attention, but there is increasing evidence that psychological and social interventions may be equally effective."
The participants in the trials will attend groups which meet weekly for 12 weeks.
They will then continue reminiscence work monthly for a further seven months or receive the 'usual' care in day care centres.
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