Study in Cognitively Intact Seniors Aiming to Assess the Effects of Meditation Training

As the number of older people in Europe grows, increasing healthy life years is a priority. As people live longer, ensuring good mental as well as physical health into later years is becoming ever more important. Cognitive decline, dementia (e.g. Alzheimer's Disease, AD), sleep disturbances and depression, all related to psychological distress and anxiety, are significant drivers of reduced quality of life in older adults. This project builds on evidence that meditation practice have the potential to downregulate these adverse factors and positively impact mental and neurological conditions including AD.

Understanding of the neurocognitive mechanisms of meditation is still limited. Meditation can be conceptualized as "a set of complex emotional and attentional regulation strategies developed for a variety of purposes including the development of emotional well-being and balance". Affective (emotional) and cognitive (attentional) control are therefore the most likely mechanisms by which meditation could impact aging and AD. Specifically, meditation could enhance the controlling role of mid-brain structures and the executive network over structures involved in memory, emotions, and regulation of the immune system. This would lead to better emotional and cognitive control which in turn would be associated with improved mental and physical health.

Eligibility Criteria:
1. Inclusion Criteria :

   For all participants
   * Age ≥ 65 years ;
   * To be autonomous
   * Live in their home;
   * Educational level ≥ 7 years (from the Preparatory Course (First grade) included);
   * To be registered to the social security system ;
   * To be motivated to effectively participate in the project and to sign the consent form in agreement with the local ethic committee ;
   * Neuropsychological performances within the normal range (according to age, sex, and educational level), as assessed by the diagnostic battery.

   For participants without previous meditation practice
   * French mother tongue;
   * Available for the trial duration (24 months);
   * Retired since 1 year or more;
   * No preference regarding the intervention group ;
   * Not having regularly or intensively practiced meditation or comparable practices (yoga, Qi Gong, Alexander technique) as follows :

     * more than one day per week for more than six months consecutively over the last 10 years,
     * intensively (internship or retreat \> five consecutive days) over the past 10 years,
     * more than 25 days of retreats (cumulatively) prior to the last 10 years ;
   * Not speaking English fluently.

   For expert meditators :
   * Formal meditation practice \> 10 000 hours in the whole life, including at least 6 cumulated months of retreat;
   * Daily meditation practice (at least 6 days/week, 45 minutes/day);
   * Mindfulness meditation practice (i.e. mindfulness, samatha/vipassana, zazen (zen), shikantaza (zen), focused attention, mahamudra/Dzogchen, and compassion/loving jindness (tonglen, metta/karuna, bodhichitta)
2. Exclusion criteria :

   * Contraindication to MRI or PET Amyvid® ;
   * For security reasons realted with the use of Amyvid®, a blood sampling allowing to measure hepatic and renal functions will be performed at the V1 visit before the PET-Amyvid® scan. In case anomalies are detected of grade 3 or higher severity, the PET-Amyvid® scan will not be performed.
   * Hypersensitivity to Amyvid®
   * History or presence of a major neurological or psychiatric disorder (including an addiction to alcohol or drugs);
   * History of cerebral disease (vascular, degenerative, physical malformation, tumor, or head trauma with loss of consciousness for more than an hour);
   * Presence of a chronic disease or acute unstable illness (respiratory, cardiovascular, digestive, renal, metabolic, hematologic, endocrine or infectious);
   * Current or recent medication that may interfere with cognitive action or radiological measures (psychotropic drugs, antihistamines, anti-Parkinsonian drugs, benzodiazepines, non-steroidal anti-inflammatory agents, antiepileptics, central analgesic and muscle relaxants);
   * Under legal guardianship or incapacitation;
   * Inclusion in another biomedical research protocol at baseline, if including use of a radiolabel for radiological measures;
   * Physical of behavioural inhabilities to perform the follow-up visits as planned in the study protocol.