Cognitive Aspects of Mental Activity during Sleep
Piercarla Cicogna, Corrado Cavallero, M Bosinelli
The American Journal of Psychology 1991 DOI: 10.2307/1423247 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study Peer reviewed |
|---|---|
| Sample size | 27 |
| Population | Human sleeping subjects awakened during four sleep conditions |
| Citations | 70 |
| Key findings | Dream reports and their associated memories showed a basic homogeneity across early and late sleep onset, Stage 2, and REM sleep. The authors argue this supports a single dream-generation system in which the same cognitive mechanisms operate at different levels of engagement, rather than multiple systems dependent on the physiological characteristics of each sleep stage. |
Abstract
Upon nighttime experimental awakening of 27 subjects in four sleep conditions (sleep onset early; sleep onset late; Stage 2; and rapid eye movement, REM, sleep), 108 dream reports and their association reports were collected. Dream reports were analyzed for length (temporal units) and content categories (continuity; implausibility; presence of the dreamer [i.e., "the self"], a setting, characters). Associations were classified as episodic, abstract self-referred, and semantic memories. The two sets of results tend to show a basic homogeneity among mentation reports in the four sleep conditions considered. These findings are interpreted as supporting the hypothesis that the same cognitive mechanisms operate, at different levels of engagement, in dream generation rather than the hypothesis of multiple dream-generation systems dependent upon the physiological characteristics of the various sleep stages.