Failure to Recall Dream Content: Contentless vs Dreamless Reports

Data from three separate studies support the hypothesis that contentless and dreamless reports obtained in dream-recall experiments are functionally, as well as descriptively, different phenomena. Distributions of percentages of contentless and dreamless reports (a) for different phases of the menstrual cycle, (b) over a three-day recording period, and (c) for length of total sleep time were qualitatively different. It is suggested that, at minimum, investigators should distinguish between contentless and dreamless reports rather than viewing them as a homogeneous nonrecall phenomenon.