Morning Dream Recall: These Are the Factors That Influence It

The ability to remember dreams is influenced by multiple factors, including age, attitudes about dreaming, sleep patterns, and season, according to the results of a study published in Communications Psychology.

Dreams have been associated with learning and memory consolidation and psychophysical health. However, there is a paucity of data about the factors influencing dream generation and recall.

Researchers from the IMT School for Advanced Studies Lucca in Italy recruited healthy adults (N=204; mean age, 35.1 years; women, 55%) aged 18 to 70 years between 2020 and 2024 for this study. The participants underwent a cognitive battery, 15-day sleep assessment, and a cognitive battery follow-up. During the sleep assessment, 42 participants (mean age, 30 years; women, 57%) wore an actigraph at night and in the morning, all participants audio recorded the thoughts and dreams they had during sleep. A contentful dream (CD) was defined as a dream with any semantic content, a white dream (WD) as a dream experience without recall, and no dream (ND) as having no dream experience.

The researchers collected a total of 2900 morning dream reports for an average of 14.22 reports per participant.

The proportion of morning reports with a CD was 0.58, a WD was 0.14, and ND was 0.28, corresponding to an average of 5.04 dream experiences per week.

The frequency of dreams according to the morning diaries was higher than self-reported frequency (P <.0001), but the frequencies were correlated (r, 0.46; P <.0001).

In a principal component (PC) analysis using 24 actigraphy indices, the first 4 PCs explained 87.74% of the variance in dream outcomes.

Having a CD or WD associated with PC2 (estimate, 0.1408; P =4.93E^-7), attitude about dreaming (estimate, 0.088294; P =3.80E^-5), proneness to mind wandering (estimate, 0.26467; P =.0001768), and verbal memory (estimate, 0.055183; P =.017517) relative to ND.

Having a CD associated with age (estimate, -0.029499; P =.00045411), vulnerability to interference (estimate, -0.052596; P =.00051982), educational attainment (estimate, 0.083547; P =.012076), and attitude about dreaming (estimate, 0.050675; P =.037586).

Long, light sleep, calculated by PC2 scores, were higher on nights with a dream experience than on nights with ND (q <.001). Some evidence suggested that the proportion of rapid eye movement (REM) sleep associated with dream recall (P =.025), but this relationship was attenuated with adjustment.

Stratified by time of year, the adjusted probability of recalling a dream was significantly lower in the winter than the spring (q <.05). Adjusted PC2 scores were also observed to be higher in autumn (q <.001) and spring (q <.01) than summer.

This study may have been limited by not collecting actigraphy data from all participants.

“Our study demonstrates that specific inter-individual (trait) and intraindividual (state) variables influence the likelihood of having and recalling a dream experience. Notably, our findings show that similar overnight sleep patterns increase the probability of both contentful and white dreams, and that the memory retention for dream content may be primarily lost due to interference by external or internal factors,” the researchers concluded.