Fréquence et contenu du rapport de rêve : approches comportementales et neurophysiologiques

Abstract

Since the dawn of time, humans have sought to understand the nature and meaning of their dreams. However, despite millennia of philosophical speculation and more than a century of scientific exploration, several questions regarding dreams remain pending.One question that constitutes the core problematic of this thesis relates to why there are such individual differences in the frequency of dream recall, or in other words, why some people remember up to several dreams per morning (High-recallers, HR) while some hardly ever recall one (Low-recallers, LR). To characterize the cerebral and behavioral correlates of this variability, we compared the sleep microstructure (Study 1), as well as the brain functional connectivity in the minutes following awakeningfrom sleep, a period marked by sleep inertia (Study 2). Among other results, we have shown that just after awakening, HR demonstrated a greater functional connectivity within regions involved in memory processes (default mode network). We proposed that this reflect a differential neurophysiological profile, which could facilitate in HRthe retrieval of dream content upon awakening. Second, the numerous answers to the recruitment questionnaire of this study allowed us to conduct an epidemiological survey to characterize the sleep and dream habits of a large sample of French college students from Lyon 1 University (Study 3). In another study, we focused on the relationships between waking-life and dream content (Study 4). Our results enhanced and refined our comprehension of the factors influencing the likelihood of incorporation of waking-life elements into dreams, and provided support for the hypothesis of an active role of dreaming in emotional regulation.Lastly, we designed a free and open-source software dedicated to the visualization and analysis of polysomnographic recordings (Study 5), which aims at providing an intuitive and portable graphical interface to students and researchers working on sleep