People who experience fear in their dreams are more likely to wake up in a bad mood, according to a new study that adds scientific weight to something many people already sense when they drag themselves out of bed after a nightmare.
The study, published in the journal Sleep, found that dream content, specifically whether a person felt fear or joy while dreaming, can influence psychological state in the morning. Researchers were careful to note that the findings do not prove bad dreams cause a low mood, but the association was measurable and consistent across participants.
Those who experienced fear in their dreams were 7% more likely to have a lower mood in the morning. Those who experienced a mix of joy and fear were around 20% more likely to wake up in a calm, placid state. Individuals who reported a high level of joy in their dreams were 9% more likely to wake up feeling positive.
The study drew on data collected through a sleep diary and morning mood survey sent to participants over a year-and-a-half period, during which each person completed a maximum of 55 surveys. The surveys tracked factors including bedtime, sleep latency, how long participants spent awake after initially falling asleep, and the time of their last awakening before getting up. Participants were also asked to report on their dream recall and the emotional content of those dreams.
Nicole Andreoli, a licensed psychologist and author of "Mindfulness & the ADHD Parent," said the findings align with what she observes in clinical practice, even though she was not involved in the research. "Dreams are such a popular topic in therapy. I find that clients often ask about dream interpretation and trying to understand their meaning, or link their significance to daily life," she told Healthline. "This is especially true for the more emotionally charged dreams because they do tend to influence morning mood. Many of my clients talk about subsequently waking up experiencing anxiety or depressed mood due to the content of their dreams."
Alex Dimitriu, a physician double board certified in psychiatry and sleep medicine and founder of Menlo Park Psychiatry and Sleep Medicine, said the findings fit within a broader scientific understanding of what happens in the brain during REM sleep, the stage in which most dreaming occurs. "It has been proposed that REM sleep, in which dreaming occurs, is almost a virtual therapy or sandbox environment," Dimitriu said. "In the dream state, and absent any norepinephrine (adrenaline), the brain replays emotional experiences to plans for future ones. Dream sleep is like an emotional playground for the mind."
Dimitriu, who also was not involved in the study, suggested that people with more active dream lives may experience better emotional regulation over time, as their sleeping brains spend more time processing emotional material.
The researchers emphasized that more work is needed to understand the mechanisms behind the connection between dream content and waking mood. The study does not offer guidance on how to change dream content, but its authors suggest that dreams may serve a functional role in emotional processing, a question that sleep scientists have been examining for decades with increasing precision.
