As the night wears on, your dreams escalate in weirdness, finds a small new study published in the journal Dreaming.
For two nights, the researchers outfitted 16 people with a sleep-monitoring eyelid sensor and head sensor, then proceeded to wake each person up at four different times in the night. Sleepers were asked to say what they'd been dreaming, and in the morning, they listened to their dreams and answered questions about them, like how related the dreams were to their waking life.
“We found that dreams were increasing in bizarreness from the early to late night,” says study author Dr. Josie Malinowski, a lecturer in cognitive psychology at the University of Bedfordshire in the U.K. The later dreams were more fantastical, impossible, and completely unlikely to ever happen in real life, “like a wild animal tearing up your back garden,” she says. Dreams also tend to become more emotional—in equal ways positive and negative—as the night progresses.
In the early stages of sleep, people dream more about media they’d consumed during the day, like a movie they’d watched or book they’d read. Dreams about events that happened during waking life, however, were more robust later in the night.
Some dream researchers, including Dr. Malinowski, believe you can prime the brain to dream about a particular topic through "dream incubation," and that dreams might be able to help us problem-solve. Exploring these dreams can help people understand their own behavior, thoughts and feelings, Dr. Malinowski says.
And through her research, she's trying to get people to take dream therapy more seriously. “People really enjoy it,” she told TIME. “Dreams are like a safe space. People feel like they haven’t generated them because they’re often so bizarre. [But] they’re a safe way to explore the self.”