Auditory Awakening Thresholds and Dream Recall in NREM Sleep

Whereas earlier research had shown that Ss with lower auditory awakening thresholds (AATs) reported more dreams on awakenings from non-rapid eye movement (NREM) sleep, this study of 4 Ss over several nights each indicated no relationship between Stage 2 NREM dreaming and within-subject, within-night variations in AAT. Subjectively “deep” Stage 2 sleep was associated with high AATs and with reports of Stage 2 dreaming. AATs declined over successive nights of laboratory sleep. Earlier reports of similar AATs for Stage REM and Stage 2, a decrease in AAT with time of night, and no relationship between AAT and time since last awakening were all confirmed. Stage 2 awakenings made close together in time yielded more reports with similar manifest content.