Sleep-related experiences [Watson, D. . 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 , altered-consciousness tendencies , psychological distress, childhood maltreatment , and life stress in young adults. Both (...) types of SREs 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. (shrink)