Dissociative symptoms refer to disturbances in the integration of thoughts, feelings, and experiences into consciousness and memory. They overlap with schizotypical features, notably paranoid thinking. In recent studies, I found evidence that labile sleep-wake cycles a) lead to dreamlike mentation invading the waking state, b) produce memory failures, and c) fuel dissociative symptoms. This pattern of findings may inspire new treatments for dissociative symptoms (e.g., interventions that focus on normalization of the sleep-wake cycle), which is important because dissociative symptoms are notoriously recalcitrant to pharmacological and psychotherapeutic interventions. In this proposal, I aim to study the mechanisms underlying the link between sleep problems, dissociative symptoms, and paranoid thinking. One candidate mechanism might be emotional memory processing during REM sleep. I propose to conduct three studies; 1) a cross-sectional study to look at the correlations between dissociation, paranoid thinking, sleep aberrations, and memory measures; 2) a sleep deprivation experiment to test whether sleep disruption per se induces dissociative symptoms, paranoid thinking, and deteriorated emotional processing, and 3) a Cognitive Behavioural Therapy (CBT) intervention study aimed at sleep normalization to explore whether sleep improvement reduces dissociative symptoms and paranoid thinking through the improvement of emotional memory processing.