- Sleep-related experiences [Watson, D. (2001). Dissociations of the night: Individual differences in sleep-related experiences and their relation to dissociation and schizotypy. Journal of Abnormal Psychology, 110, 526–535] refer to a host of nocturnal altered-consciousness phenomena, including narcoleptic tendencies, nightmares, problem-solving dreams, waking dreams, and lucid dreams. In an attempt to clarify the meaning of this construct, we examined cross-sectional and longitudinal associations of sleep-related experiences (SREs), altered-consciousness tendencies (i.e., dissociation and transliminality), psychological distress, childhood maltreatment (i.e., abuse and neglect), and life stress in young adults. Both types of SREs (general SREs and lucid dreaming) were found to be distinguishable from altered-consciousness tendencies. Transliminality emerged as a longitudinal predictor of both general SREs and lucid dreams. Psychological distress and an increase in life stress predicted an increase in general SREs over a 3-month interval. We conclude that transliminality is a general altered-consciousness trait that accounts for some of the individual differences in sleep-related experiences, and that general sleep experiences are an outcome of psychological distress and life stress.