Ultradian and circadian modulation of dream recall: EEG correlates and age effects.

Dreams occur during both NREM and REM sleep, which are regulated by homeostatic, ultradian, and circadian processes. This review examines whether the ultradian NREM-REM cycle, gated by the circadian clock, influences successful dream recall, and identifies key electrophysiological correlates of dream recall during both sleep stages. It also explores age-related changes in the circadian and ultradian regulation of dream recall and its EEG correlates. Understanding the specific frequency and topographical EEG differences before dream recall may reveal the cerebral mechanisms underlying this cognitive process and their physiological significance.

Study at a glance

Abstract

Dreaming occurs during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep, which both are regulated by homeostatic, ultradian, and circadian processes. However, the magnitude of how ultradian REM and NREM sleep and its EEG correlates impact onto dream recall remains fairly unknown. In this review, we address three questions: 1. Is there an ultradian NREM-REM sleep modulation in successful dream recall, which is gated by the circadian clock? 2. What are the key electrophysiological correlates that account for dream recall during NREM and REM sleep and 3. Are there age-related changes in the ultradian and circadian regulation in dream recall and its electrophysiological correlates? Knowledge on the specific frequency and topography NREM and REM sleep differences prior to dream recall may pinpoint to the cerebral correlates that account for this cognitive process, and hint to their possible physiological meaning.