Fig. 1.

a Participants first learned 80 word pairs (A–B) up to a criterion of 60%, by a repeated cued recall procedure (see Methods section for details). Afterwards at ~22:30, they took 175 mg d-cycloserine or placebo. At 23:00 the participants in the Sleep group went to bed and polysomnographic recording was performed, whereas the Wake participants watched documentaries about planets. All participants received breakfast at 07:45 and watched animal documentaries until 18:00. Afterwards, at 18:30, the participants learned 80 new word pairs in three consecutive runs and finally retrieved the original 80 word pairs. b Mean and standard error of the mean (SEM) of the amount of correctly recalled word pairs in total, c in the Sleep experiment, and d in the Wake experiment during the three runs of the New Learning phase are shown