Effects of cognitive training interventions on the cognitive and everyday functioning of older adults – systematic overview of meta-analyses

As the population is aging, the prevalence of age-related cognitive decline is now the highest in history, with a long-term trend of increase. Many studies have examined whether cognitive training (CT) is an effective intervention for preventing and slowing down the neurodegenerative processes of aging so as to enable independent functioning and active living in older age. In order to summarize the available data, we conducted a systematic literature overview of meta-analyses investigating the efficacy of various CT interventions on cognitive and subjective/functional outcomes in healthy older adults, older adults with mild cognitive impairment, and older adults with subjective memory/cognitive complaints. We searched six databases (Web of Science, Scopus, PsycINFO, MEDLINE, CINAHL, and Cochrane Library) and identified eight eligible meta-analyses. The quality of the included meta-analyses was assessed using the AMSTAR-2 checklist. The confidence ratings were “moderate” for one meta-analysis, “low” for two meta-analyses, and “critically low” for five meta-analyses. Although there is a need for better methodological standards for meta-analyses, the available evidence suggests that CT is an effective intervention for improving both cognitive and subjective/functional outcomes in older adults. Future research should be more oriented toward measures that indicate the practical efficiency of CT and should be more specific regarding the type of CT intervention, so as to elucidate the potentially different underlying mechanisms of their functioning.