Sleep-related memory consolidation during pregnancy

Motor learning requires repeated practice, which may be exhausting for older adults, especially during rehabilitation. Among less physically demanding interventions to preserve/enhance motor functions in elderly people, motor imagery (MI) training has gained attention. However, we do not know whether MI training might benefit from sleep in older adults, as shown in young adults. This project will focus on four research questions: (1) Does acquisition of a fine and a gross motor task supported by MI training differ between young and older adults? (2) Does the effects of sleep versus wakefulness on motor learning after MI training differ between these tasks and age groups? (3) How does brain activity during MI of these two tasks differ from rest, and does it change after learning in the two populations? (4) How is brain activity during sleep associated with the learning process of the two tasks and in the two age groups? We will test 120 young (20-35yrs) and 120 older adults (65-80yrs). Their sleep-wake cycle will be monitored with sleep logs and actigraphy for one week. Sleep will be recorded during a baseline night without any motor learning and during the night following motor learning (i.e. experimental night). A classical finger-tapping task, and a new whole-body task (WBT) will be used. Training will be either followed by 12h containing sleep or wakefulness. MI training should be beneficial compared to no-training for both tasks and age groups, but the impact of sleep on motor learning should be different. More specifically: (i) for both tasks the motor performance after MI training should be greater in young adults compared to older ones; (ii) sleep-dependent motor learning should be observed in both tasks for the young but only in the WBT for the elderly; (iii) a change of brain activity during MI of the two tasks should be found after learning, but the degree of modulation could differ between tasks and age groups; (iv) young adults should show higher correlations between brain activity during sleep and motor learning over sleep, than older adults. This project notably innovates by the use of a new ecological but still controlled whole body task. It will provide significant advances in our understanding of the neural underpinnings of motor learning by motor learning and sleep, and could directly lead to cost-effective applications in geriatric rehabilitation. Dr. Saimpont from the University of Lyon (France), and Dr. Hoedlmoser from the University of Salzburg (Austria) will be responsible for this project.