Interactions entre le sommeil, l’attention et le contrôle postural chez des sujets jeunes et âgés
Falls are an important cause of injuries and mortality, especially in the work force and in the elderly population. This thesis investigates the effects of sleep loss on postural control according to age and explores the influence of attentional, perceptual and motor resources on the relationship between sleep and postural control. Young and older participants completed various postural tasks on force plates after a night of sleep and after 25 hours of sleep deprivation. Center of pressure range and velocity were measured with eyes open and with eyes closed while participants performed an interference task, a control task, and no cognitive task.  Sleep deprivation increased the range of center of pressure in both age groups and center of pressure speed in older participants only. Moreover, in elderly participants, the destabilizing effects of sleep deprivation were more pronounced with eyes closed. The interference task brought younger participants to adopt a more static postural strategy when sleep deprived. However, in older participant, the interference task did not alter postural control beyond the destabilization induced by sleep loss.  These observations suggest that sleep loss has greater destabilizing effects on postural control in older than in younger adults, especially when vision is altered. It is therefore proposed that sleep debt may be a significant risk factor for falls.
vision cognition sleep postural control vision cognition ageing