How Awakenings Shape Dream Recall: A Multilevel Study

Dream recall varies greatly between people and from night to night. Nocturnal awakenings are thought to help encode and retrieve dreams, but it was unclear whether the frequency, duration, sleep stage, or timing of awakenings matters most. Analyzing two cohorts (708 adults across three waves and 124 adults with high dream recall across multiple nights), trait-level dream recall was associated with a specific pattern: more habitual long REM awakenings and short NREM awakenings. State-level analysis showed that nights with more short and medium REM awakenings increased the likelihood of morning dream recall, while more long REM awakenings increased the likelihood of recalling dream content. Findings support arousal-retrieval and functional state-shift models with important nuances.

Study at a glance

Abstract

Abstract Dream recall varies substantially both between individuals and from night to night within the same individual. Although nocturnal awakenings are thought to facilitate the encoding and later retrieval of dream experiences, it remains unclear whether dream recall is shaped primarily by awakening frequency or by more specific awakening characteristics, including duration, sleep stage, and timing within the night. Here, we analyzed two cohorts: cohort 1 consisted of 708 adults spanning the full range of dream recall frequency, assessed across three waves with home sleep recordings and questionnaire-based dream recall frequency measures; cohort 2 consisted of 124 adults with high dream recall frequency, assessed across multiple nights with home sleep recordings and daily dream reports. Using multilevel models with within-between decomposition, we examined trait-like and state-like associations between awakening measures and dream recall outcomes. At the trait level, both questionnaire-based dream recall frequency in cohort 1 and daily dream recall (i.e., a sense of having dreamed) in cohort 2 were associated with a specific nocturnal awakening profile: more habitual long REM awakenings and short NREM awakenings, with REM awakening effects remaining robust after adjustment for sleep duration. At the state level, in cohort 2, nights with more short and medium REM awakenings than usual increased the likelihood of morning dream recall, whereas nights with more long REM awakenings than usual increased the likelihood of morning dream content recall (i.e., remembering dream content). These findings support the arousal-retrieval and functional state-shift models, while highlighting important nuances in the associations between nocturnal awakenings and different dream recall outcomes.