It is very common to wake up from a vivid dream and forget it after a few minutes, even seconds. Dreaming occurs, especially (although not always exclusively ), during rapid eye movement (REM) sleep, according to an article published in Scientific American.
During this phase of sleep, brain activity is similar to that of the awake brain, with some very important differences. One of the main reasons is that during REM, the areas of the brain that transfer memories to long-term storage – as well as the long-term storage areas themselves – are relatively deactivated, says Deirdre Barrett, a sleep researcher at the University of California. Harvard Medical School. This may be a side effect of the role of REM sleep in memory consolidation, according to a study published in 2019 in mice in the journal Science.
Short-term memory areas are active during REM sleep, but those only hold on to memories for about 30 seconds. So to remember a dream, you generally have to wake up from REM sleep, Barrett says. If, on the other hand, you move on to the next phase of sleep without waking you up, that dream will never enter long-term memory.
REM sleep occurs approximately every 90 minutes and lengthens as the night lengthens. The first REM cycle of the night usually lasts only a few minutes, but by the end of an eight-hour night of sleep, a person has typically been in REM for about 20 minutes, Barrett says.
Therefore, the strongest correlation regarding dream memory is the number of hours slept. By sleeping only six hours, you will have less than half the sleep time of an eight-hour night. Those last hours of sleep are the most important for dreaming. And people tend to remember the last dream of the night, the one they have right before they wake up.
Traits that influence remembering dreams
According to a 2008 meta-analysis, women tend to remember some dreams more than men. Young people remember more dreams than older people, multiple studies have shown. Dream memory increases in children from the age at which they can communicate them, stabilizes between the early teens and early twenties, and then declines very gradually in adults for the rest of their lives, he says. Barrett.
However, there are many individual differences in dream memory. Some people almost never remember a dream, while others remember several each night. People who are more introverted and self-focused tend to remember more dreams, Barrett notes, while those who are more extroverted and action-oriented tend to remember fewer.
Imagination and susceptibility to hypnosis are also related to dream recall, as is creativity. Overall, according to a 2017 study, dream recall and interest appear to be linked to openness to experience, a personality trait characterized by the desire to try new things and explore unusual ideas.
A few studies that have investigated lucid dreams—vivid dreams that the dreamer remembers very well and feels in control of—suggest that some areas of the brain linked to attention are more active in people who remember more dreams, suggesting indicating that basic neurological differences may play a role.
“Some people don’t pay as much attention to their dreams while they’re happening as others, just in terms of the brain action that’s going on,” Barrett says.
Train the brain to remember
However, it is possible to train the brain to remember more of dreams, says Leslie Ellis, a clinical counselor in British Columbia and author of A Clinician’s Guide to Dream Therapy: Implementing Simple and Effective Dreamwork (Routledge, 2019). She advises clients who want to remember their dreams to take a moment when they wake up, before even moving their body, to think about what they just dreamed and remember as much as possible. In this way, sleep moves from short-term memory to long-term memory.
“Write it down right away, and then you’ll have it there,” says Ellis, “because most people get away unless they deliberately record it.”
In Western culture, dreams are often considered absurd, Ellis says. Although sometimes they may not make much sense, they often hint at emotions that people are processing in their lives. “We dream about things we don’t want to see,” she says. “During the day, we can repress a lot of those things, but dreams bring them to the surface.”
