Is anyone out there not fascinated by dreams? Dreaming is a universal human experience that’s also incredibly individual and personal. What are possibly the oldest “dream journals” – paintings on cave walls that some researchers think are records of ancient shaman dreams – date back 60,000 years, to the Paleolithic Period. And, as anyone who has a pet knows, dreaming doesn’t seem to be limited to we humans. Research into animal dreaming shows that other mammals—who have basic brain structures similar to humans—dream, too. (If my dog’s sleeping behavior is any indication of her dreams, she never actually catches that squirrel she’s chasing.)
Why do we dream?
Despite plenty of interest and research, we still don’t have an answer to this question. The purpose of dreaming is essentially still a mystery. But there are plenty of theories about why we may dream. Scientists think dreams may be:
- A way for the brain to take new information and convert it to memory
- Part of the brain’s method for working through emotional experiences of waking life
- A kind of virtual-reality simulation for the brain, allowing it to strategize, practice, and prepare for challenging real-life situations
- The brain’s way of making meaning out of internal electrical activity that goes on during sleep
The answer, say some scientists, isn’t necessarily limited to one theory: dreaming may exist for some or all of these reasons.
Why don’t we remember more of our dreams?
It’s such a strange experience: you wake from a dream and just as you begin to think about what you’ve been dreaming, your memory of the dream slips away, never to return. One theory about why most of us don’t recall dreams is that a part of our brains involved in establishing long-term memories—the hippocampus—is still in sleep mode when we first wake up. The result? Our brains can’t hang on to the memory, and so it vanishes. It may also be that some of our dreams are so mundane, our brains consider them too low-priority for memory. But the difficulty in recalling dreams is far from fully understood by scientists at this point.
Science is pretty clear about this: just because you don’t remember your dreams doesn’t mean you aren’t dreaming. A person dreams an average of 4-6 times a night. Dreams tend to get longer and more complicated as the night goes on and we spend more time in REM sleep, a sleep stage when dreams tend to be very vivid.
What are the most common dreams?
There are several themes in dreaming that cut across cultures and ages, suggesting that many of the symbols embedded in our dreams are universal. Research has identified some of the most common dreams. Recognize any of these in your own nightly journeys?
- Being chased
- Studying/school-related dreams
- Sexual dreams
- Making new discoveries—a new room in your house, finding money, etc.
Does the quality of sleep affect dreams?
Sleeping poorly—and not sleeping enough—can have a pretty big impact on dreams. When we’re sleep deprived, even from a single night of not sleeping enough, we’re likely to have more intense, vivid, and frequent dreams the next time we sleep.
- People with insomnia have more negative dreams than sound sleepers.
- People who snore may be more likely to have anxiety dreams than non-snorers.
- People with sleep apnea have more frequent nightmares and emotionally upsetting dreams, and the worse their sleep apnea, the more troubling their dreams.
- People with sleep disorders or restless, disturbed sleep are actually more likely to remember their dreams, likely because they are waking up so often throughout the night.
One tip sleep and dream experts suggest if you want to increase the chances you’ll remember your dreams? Give yourself the intention to remember them, at bedtime. I’ll be giving that one a try, tonight.
Written by Caitlin Reynolds