It is said that five minutes after the end of a dream, we have forgotten 50 percent of the dream's content. Ten minutes later, we've forgotten 90 percent of its content. Why is that? We don't forget our daily actions that quickly.
There are some people who say that they never dream. It's unclear if this is possible, but we do know that some people rarely or never remember their dreams. In the early 2000s, neuropsychologist and psychoanalyst Mark Solms found that people who developed lesions in the white matter of their medial prefrontal cortex reported that they stopped dreaming. Dream recall can vary person to person, but it can also vary day to day for one person.
Researchers have been studying dream recall for decades. Even so, we don't know whether people who never remember their dreams actually dream less than people who frequently remember their dreams, or whether they are just forgetting their dreams more easily. People who have reported never remembering their dreams have been able to recall them when they are awakened at the right moment. Many people have formed hypotheses about why remembering dreams is so notoriously difficult.
Freud theorized that we forget our dreams because they contain our repressed thoughts and wishes, so we don't want to remember them anyway. Other research points to the simple reason that other things get in the way. We are forward-thinking by nature, so remembering something when we first wake up is difficult.
Dreams may be so hard to remember because the hippocampus, a structure in the brain responsible for learning and memory processes, is not fully active when we wake up. This could result in a dream being present in our short-term memory, but not yet able to move to long-term storage.
Some researchers believe that changing levels of the neurotransmitters acetylcholine and norepinephrine are part of the reason we forget our dreams. Others think that some dreams may just be too useless to remember, so the brain tends to discard them. And some scientists think that people with certain personality traits — like those who are prone to daydreaming and introspection — have less difficulty remembering their dreams.
Despite the unknowns around dream recall, there are some measures that we can take to increase the likelihood that we remember our dreams when we wake from our slumber.
Those who believe we have a lot to learn about ourselves from our dreams are big proponents of dream journals. Here are some steps you can take to increase your dream recall:
- "Well, the first thing is that people need to understand, they need to sleep long enough to remember their dreams. Because the second half of the night is the one that is dominated by REM sleep," neuroscientist Ribeiro says. "If you cut your sleep short, you will tend to have poor dreams to report."
- Ribeiro also says that what you do before going to bed is important. Activities like drinking alcohol, using cannabis, or exercising too late can negatively affect the quality of our dreams and our ability to remember our dreams upon waking.
- When you go to bed, tell yourself you will remember your dreams.
- If we wake up straight out of a dream, we are more likely to remember it. We are also more likely to remember dreams that are vivid and coherent. Set your alarm to go off every hour and half so you'll wake up around the times that you leave REM sleep, when you're most likely to remember your dreams. (Or, drink a lot of water before you go to bed to ensure you have to wake up at least once in the middle of the night!)
- Keep a pad and pencil next to your bed.
- Try to wake up slowly to remain within the "mood" of your last dream. "People will be quite surprised that after years of not remembering anything," says Ribeiro, "they can suddenly remember pages and pages of dreaming."