This is a meta-analysis and systematic review of studies exploring the relationship between the use of digital technology and cognitive ageing in adults over 50. These types of studies have the most scientific evidence. In addition, it is published in a journal with a very high impact index.

The findings indicate that greater use of digital technologies was linked to a lower risk of cognitive impairment and slower rates of decline, even after considering various factors. The study suggests that interaction with technology could benefit cognition as we age, although more research is needed to understand the causal mechanisms and specific types of technological exposure. It is fully in line with an article we published in 2021, which is one of the articles the meta-analysis used to conduct the study.

The implications for the real world clearly involve the use of technology as cognitive stimulation.

The society in which we live is immersed in the use of so-called digital technologies in many areas and environments. We use mobile phones, computers, video and imaging devices on numerous occasions throughout our lives. Is this use of digital technologies modifying our brains in any way, and thus our cognitive abilities?

On the other hand, brain damage may cause cognitive deficits in one person, but not in another. This concept can be applied to any clinical situation as long as there is no direct correspondence between a given brain change and cognitive function. The concept of ‘cognitive reserve’ emerged to explain the lack of direct correspondence between a degree of brain damage and associated clinical or cognitive manifestations, i.e. between having the lesions of a disease and developing its symptoms. The brain's ability to counteract the deleterious effects of ageing or disease is associated with exposure to environmental variables or lifestyles such as those we have been discussing: cognitively stimulating environments, sleep, physical activity, stress reduction and socialisation, among others.

In this context, one might ask whether lifetime exposure to digital technologies could affect our cognitive reserve and thus diminish our cognitive abilities, or whether the relationship would be in the opposite direction, with technology promoting behaviours that foster cognitive reserve and better cognition.

To try to answer this question, the authors of this paper analysed 57 research studies conducted on a total of 411,430 people. They repeated the analyses of their work by limiting it to research of the highest methodological quality. In both analyses, they found that the use of digital technologies throughout our lives is associated with a lower risk of cognitive decline. Taking the results as a whole, we could include the use of digital technologies as another factor that could help counteract the deleterious effects of ageing or even certain diseases, contributing to an increase in cognitive enhancement.

This could be of great significance for a society in which digital technologies are profoundly transforming the way we live, work and interact.

The press release appropriately reflects the main findings of the study, the use of digital technologies, such as the internet, computers and smartphones, is associated with a lower risk of cognitive decline and dementia diagnosis in adults over 50 years of age. Furthermore, it highlights that these benefits are not explained solely by demographic, socioeconomic or health factors, which supports the hypothesis of a protective effect of technology on cognitive function.

The meta-analysis has a solid basis, integrating data from 57 studies involving more than 411,430 participants. It follows rigorous methodological criteria, such as the PRISMA guidelines for systematic reviews, and incorporates quality assessments using the National Heart, Lung, and Blood Institute (NHLBI) tool. The results show remarkable consistency by restricting analyses to the highest quality studies. We also controlled for relevant confounders such as age, education, health status and various proxies for cognitive reserve.

This work aligns with and extends previous evidence on cognitive reserve theory - not only traditional activities, such as reading or playing board games, but also the regular use of digital technologies, may contribute to preserving cognitive health in old age.

However, the study has some limitations. Although the total number of participants was high, the number of studies included in the moderation analyses limits the statistical power to detect moderating effects. In addition, being mostly based on observational studies, causality cannot be established. Many measures of digital exposure were based on self-reports and lacked information on the onset of use of technologies such as the internet or smartphones, which restricts the understanding of exposure patterns and their cognitive impact. Also some indicators of cognitive reserve, such as level of intelligence or acquisition of new skills, have been little explored. Finally, most of the studies were conducted in upper-middle-income countries, limiting the generalisability of the results to other contexts.

A particularly novel aspect of the meta-analysis is that it works with the so-called ‘digital pioneers’, the generation that led the global technological revolution and is now beginning to reach ages at which the risk of cognitive decline and neurodegenerative diseases is increasing.

The practical implications of these findings are relevant. Encouraging access to and moderate use of digital technologies among older adults could be an effective strategy to prevent cognitive decline. The study also highlights the need to develop accessible and tailored digital literacy programmes for older adults, promoting a balanced use that maximises benefits and minimises risks. This meta-analysis provides robust evidence that technology, used appropriately, can be a powerful ally in promoting healthy cognitive ageing and preserving functional autonomy in old age.