Fig. 1.

(A) Schematic of the experiment. For 10 consecutive days participants were asked to complete a daily log. On the night of the 10th day, they slept in the sleep laboratory and were monitored using polysomnographic recordings. They were awoken after 10 min of REM or SWS sleep, and were asked to report their dreams. Approximately 4 weeks later they were asked to identify if parts of the dream reports collected in the sleep laboratory matched parts of the 10 daily logs (see Methods). (B) Mean number of waking-life experiences across the 10 daily log days identified by the participants as being incorporated in REM dreams. Per participant, the mean number of incorporations of recent (days 1/2) and older (days 3/4, 5/6, 7/8 and 9/10) waking experiences in REM dreams was calculated (for participants who had only one REM dreams, this unique value was used). The mean across participants was then calculated and is displayed in Figure 1B. Error bars represent s.d. Daily log number refers to the number of days between completing the log and going to the laboratory (e.g. items from daily log 7 occurred 7 days before the night in the laboratory). (C) Examples of 30 s-long recordings (F3, F4 and bipolar EOG) in REM sleep prior to an awakening with a dream report. Three examples from three different participants are displayed. In the dream reports following these REM sleep periods, participants identified 4, 2 and 0 recent incorporations, respectively (from top to bottom panels). EOG are from bipolar montage and the hatched areas characterize EOG events as automatically detected (see Methods).