Here’s What’s Going on When You Dream at Night

Humans didn't start dreaming at a fixed point in history. Our nocturnal minds have always taken us on adventures. Dreams influenced ancient civilizations' foundation myths, and religious books emphasized that they were vehicles for divine messages to prophets and holy men.

In the last 100 years, neuroscientists have sought answers about the purpose of dreams, and there are still many question marks.

We spend approximately two hours dreaming every night, but the most memorable dreams occur during the rapid eye movement (REM) stage at the end of each five-stage sleep cycle. An hour and a half after drifting off, our skeletal muscles become paralyzed, possibly to prevent dream-related injuries, and our heart rate and breathing increase.

Dreams occur as the brain tries to reinforce newly formed memories and, likely, to help process knowledge and emotions. They meld the familiar with the fantastical—the brain may find connections that aren't obvious to us.

Daydreams are thoughts that distract us from our surroundings, and they happen when there's a lack of stimulation. Nightmares are dream sequences that induce fear and can occur when we're stressed, sick, sleep-deprived, or experiencing the side effects of medication.

Sweet dreams can be sad, too, when we wake to disappointment that events we just experienced are not real. Then there are lucid dreams...

Lucid dreams are those in which the dreamer is aware that they are dreaming. Christopher Nolan made an entire sci-fi blockbuster, Inception, about the concept. To achieve this state, lucid dream training is often necessary. These dreams can go on for as long as 45 minutes. A 2021 study shows that lucid dreamers can communicate with scientists via eye and hand signals.

Parasomnias are sleep disorders that can be quite frightening. They take place while drifting off, sleeping, or waking up. People experiencing parasomnia are unaware of or not in control of their actions. The sleeping person can experience hallucinations that make them dread bedtime.

REM sleep behavior disorder (RBD) results in the person physically acting out their dreams, which can be dangerous. Men over 50 are most likely to experience this sleep disorder. Neurological disorders, such as Parkinsons, and certain medications may also play a role in RBD. While hallucinations are common, RBD and night terrors are rare.

People who struggle to remember their dreams tend to fall asleep quickly and sleep without disturbances. To recall dreams, we need to induce a disruption. An alarm clock in the middle of the night can help, but so can a few glasses of water that force us to go the bathroom during the witching hour. Keep a notebook next to your bed for journaling.

As you go through your pre-sleep routine, actively think about remembering your dreams. Then, when you're waking up after sensing a dream, don't open your eyes, move or speak, or it will wipe away the memory. This routine helps the majority who try it.

Maybe. By using similar techniques for dream recollection, such as mantras and prompts, you could influence the course of your nightly sojourns. You can rarely do much more than that, such as control what ultimately happens. But many a creative idea has spawned from dreamland.

Einstein came upon the theory of relativity thanks to a dream about jumping cows.

For a long time, researchers thought rapid eye movements were random or that their only purpose was to keep eyes lubricated. Though their full purpose has yet to be determined, a recent study suggests that the eye movements we make during REM sleep could be linked to objects we're looking at in our dream's imagined world.

Doggies do dream—science says we can assume this based on the fact that dog and human brains do other similar things during sleep. Brain wave activity changes for both you and your furbaby, and dogs experience REM sleep, too, with its faster, more irregular brain waves.

Like humans, dogs likely relive aspects of their days during dreams, so Rex is probably playing fetch while stretched out on your porch.

In case you've ever wondered, men get close to 20 erections per dream. People who are born blind also dream intensely—their dreams just involve the senses they use to perceive the world. Another fun fact—not everyone dreams in color. Some only ever dream in black and white, like the old-timey films.