Sleep is known to play a role in making memories permanent. This project investigates how such consolidation of memories occurs during sleep. In 4 studies participants will keep a daily diary and will also produce reports of their dreams, either at home or in the sleep laboratory. How dream content is related to events from waking life will be studied. Incorporations of waking life events into dreams can be literal replications of events, indirect representations, or even metaphors.The timescale of incorporations will be examined, aiming to replicate the dream-lag effect, in which events from 5-7 days before the dream are incorporated as frequently as events from 1-2 days before the dream, with a dip in incorporations on days 3-4. This effect may indicate an approximately week-long memory processing function for sleep. Because Rapid Eye Movement Sleep (REM) is thought to be especially important for the consolidation of emotional memories, the project differentiates REM dreams from non-REM dreams, and emotional from neutral memories.The project also tests whether specific experimenter induced experiences are incorporated into dreams in a delayed manner, and uses a direct behavioural test of how memory consolidation occurs across several periods of sleep.

14 day daily log and dream diaries were kept by participants. After the 14 days participants identified any similarities between any part of each dream and the daily logs. All daily logs were compared to all dream diaries. The daily logs recoded daily events under 3 categories: major activities, personally important events, and major concerns. The SPSS database relates to these 3 categories of waking life events, recording for ecah category the number of incorportations per dream of that category as a function of number of days between the evebt and the dream.