Abstract :
[en] With aging, different cognitive changes are observed regarding attention, executive functions, and memory, as well as modifications of brain activity in areas underlying these processes. Nevertheless, an important variability between individuals is present. While the impact of genetic and biological factors might partially explain this variability, additional environmental factors also demonstrated a considerable influence. In line with this statement, several non-pharmacological interventions at a later stage of life were created and showed benefits on cognitive decline. One of these interventions is meditation training which received more attention these last years due to its positive effects on wellbeing as well as on cognition.
However, the majority of research on meditation practice involved a young population, making it challenging to ascertain its effectiveness on the cognition of healthy older adults. This difficulty arises from the scarcity of literature available but also from the presence of contradictory results within the existing research.
In this thesis, we aimed to investigate three questions:
1) Do meditation predispositions have an impact on aging cognition (Study 1)?
2) Does an 18-month meditation training, compared to 18-month non-native language training or to no intervention, show benefits on aging cognition (Study 2a and 2b)?
3) Do older expert meditators (people who meditated for more than 10,000 hours) have a better cognition than older adults naïve to meditation practice (Study 3)?
For this purpose, two samples of a European project called the Medit-Ageing project (or “Silver Santé Study”) were used. The first sample included 135 people naïve to meditation practice who were randomized in three groups: meditation training, non-native language training and no-intervention. The second sample had 27 expert meditators who had more than 10,000 hours of formal practice. These participants came from the Age-Well study of the project which is composed of cognitively unimpaired older people. Different measures were considered such as cognitive tasks and meditation questionnaires.
The detailed procedure of the different studies is presented in this thesis and the results are discussed in the light of the literature. Moreover, different limitations are underlined and some ideas for future works are raised.
