What makes us remember our dreams?

Some people wake up vividly recalling their dreams from the night, and can tell precise stories experienced during the night, while others struggle to remember even a single detail. Why does this happen? A new study, conducted by researchers at the IMT School for Advanced Studies Lucca, and published on Communications Psychology explores the factors that influence so called "dream recall"— the ability to remember dreams upon awakening—and uncovers which individual traits and sleep patterns shape this phenomenon.

The reason why there is such a difference in recalling dreams remains a mystery. Some studies found that women, young persons, or people with a tendency to daydreaming tend to better recall night dreams. But other studies did not confirm these findings. And other hypotheses, such as that personality traits or cognitive abilities count, received even less support from data. During the recent COVID pandemic, the phenomenon of the individual differences in morning dream recall attracted renewed public and scientific attention when an abrupt surge in morning dream recall was reported worldwide.

The new research, carried out in collaboration with the University of Camerino, was conducted in the years from 2020 to 2024, and involved over 200 participants, aged 18 to 70, who recorded their dreams daily for 15 days while their sleep and cognitive data were tracked using wearable devices and psychometric tests. Each study participant was given a voice recorder to report, every day right after the awakening, about the experiences they had during sleep. Participants had to report whether they remembered having dreamed or not, if they had the impression of having dreamed but did not remember anything about the experience, and to describe the content of the dream if they were able to remember it. For the duration of the study, participants also wore an actigraph, a sleep monitoring wristwatch that detects sleep duration, efficiency, and disturbances. At the beginning and end of the dream recording period, participants were subjected to psychological tests and questionnaires that measure various factors, from anxiety levels to interest in dreams, proneness to mind-wandering (the tendency to frequently shift attention away from the task at hand toward unrelated thoughts, or internal reflections), up to memory and selective attention tests.

Dream recall, defined as the probability of waking up in the morning with impressions and memories from a dream experience, showed considerable variability between individuals and was influenced by multiple factors. The study revealed that people with a positive attitude toward dreams and a tendency for mind-wandering were significantly more likely to recall their dreams. Sleep patterns also seemed to play a critical role: individuals who experienced longer periods of light sleep had a greater likelihood of waking with a memory of their dreams. Younger participants showed higher rates of dream recall, while older individuals often experienced "white dreams" (a sensation of having dreamt without recalling any details). This suggests age-related changes in memory processes during sleep. Moreover, seasonal variations emerged, with participants reporting lower dream recall during winter compared to spring, hinting at the potential influence of environmental or circadian factors.

“Our findings suggest that dream recall is not just a matter of chance but a reflection of how personal attitudes, cognitive traits, and sleep dynamics interact,” explains lead author Giulio Bernardi, professor in general psychology at the IMT School. “These insights not only deepen our understanding of the mechanisms behind dreaming but also have implications for exploring dreams' role in mental health and in the study of human consciousness.” 

 “Data collected within this project will serve as a reference for future comparisons with clinical populations,” adds Valentina Elce, researcher at the IMT School and first author of the study. “This will allow us to move forward the research on the pathological alterations of dreaming and their potential prognostic and diagnostic value”.