Study reveals that stimulation of the cerebellum improves memory in elderly individuals

English version: Diana Taborda

A study led by the University of Coimbra (UC) revealed that stimulation of the cerebellum improves the ability of elderly people to remember personal past events (episodic memory). The research work was led by Jorge Almeida, UC professor and researcher at the Centre for Research in Neuropsychology and Cognitive and Behavioural Intervention of the Faculty of Psychology and Educational Sciences of the University of Coimbra (CINEICC-FPCEUC), and Director of Proaction Lab.

The research findings showed the relevance of this part of the brain in delaying age-related cognitive decline, reinforcing the importance of non-pharmacological interventions to prevent or diminish this decline in healthy aging.

The study − published in GeroScience (one of the most important journals in the field of gerontology), − involved healthy people aged 60 years old or over, who were subjected to cognitive training and a non-invasive, painless neuronal stimulation technique (transcranial direct-current neurostimulation). Jorge Almeida explains that the research showed "an improvement in the ability of healthy elderly people to remember word lists, after only twelve consecutive sessions of cognitive and neuronal stimulation".

As for the improvements shown, “individuals who received stimulation of the cerebellum were able to remember 4 more words on average, out of a total of 16, when compared to the other control groups", describes Almeida.

The memory improvement was accompanied by neural changes in the connectivity between the areas responsible for memory - i.e., the effect of stimulating the cerebellum was also visible in the neural structures that support episodic memory functions, improving their connectivity. Participants showed very clear episodic memory improvement both 1 day after the 12-working day stimulation program and 4 months later, during follow-up, “causally demonstrating that the cerebellum is involved in episodic memory performance”.

Jorge Almeida also highlights that "these data demonstrate our ability to intervene, in a simple and non-pharmacological way, in one of the major complaints related to age-related cognitive decline - our ability to remember things from our daily lives".

The study, which involved a multidisciplinary and multinational team of psychologists, medical doctors and engineers from several universities (namely Coimbra, Harvard and São Paulo), also suggests a different role of the cerebellum in cognitive processes and in the functioning of the mind, which goes beyond the standard relation to the coordination and control of movement.

With life expectancy increasing, the United Nations (UN) estimates that by 2050, one in six people in the world will be over 65. This tectonic shift in demographics poses very significant challenges to society, as increased lifespan is strongly associated with cognitive decline, neurodegenerative disease, and overall frailty. The authors of the study note that episodic memory will probably be the major victim of age-related cognitive decline, and are hopeful about the results in view of the current and future demographic context, also emphasising the importance of non-pharmacological interventions for the prevention and mitigation of cognitive decline in the elderly.

The scientific article “The cerebellum is causally involved in episodic memory under aging” is available at https://link.springer.com/article/10.1007/s11357-023-00738-0.