Sleep Stages and Verbal Memory

Abstract

Two experiments were performed in an attempt to relate sleep stages with overnight memory of consonant trigrams and paired-associates. In Exp. 1, a 20-min. learning task before sleep did not alter sleep patterns of a group of high school and college students. Further, neither delta sleep nor REM sleep nor their interaction reliably correlated with recall in the morning. In Exp. 2, the effect of pharmacological alteration of the sleep pattern was assessed. Despite a large suppression of REM sleep and concomitant elevation of stage 2, recall and relearning in the morning were not different from non-drug values. These results indicate that no sleep stage is uniquely favorable or unfavorable to verbal memory.