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Think back to the most bizarre dream of your life. Was your hamburger eating you? Did you look down and your fingers were pickles? Now, did it feel so real you had an actual “pinch me, I’m dreaming” moment? Or did it make no sense at all?

Simply put, dreams are a series of images, emotions, or thoughts that occur during sleep. They can be wonderful or terrifying, nonsensical or totally clear. Dreams come in limitless forms and have endless meanings.

While you may not know what your Zzz’s mean, you can at least know where they come from. It all starts with what happens to your brain as you drift off.

There are four stages of sleep:

Stage 1: The transition period between being conscious and unconscious. It lasts around 5 to 10 minutes.

Stage 2: Your brain starts to produce sleep spindles (aka brain waves). While technically asleep, you’re not fully done counting sheep.

Stage 3: Your brain begins to produce slower electrical waves. Your muscles cease activity and it’s harder for you to wake up. This is when your body and immune system repair.

Stage 4: Rapid Eye Movement (REM) sets in about 90 minutes into sleep. Breathing becomes more rapid and your blood pressure increases. Your eyes rapidly move from side to side (hence the name). Your brain processes info from the day before and catalogues it into your memory.

Here are some dreamy fast facts:

  • Dreams typically last around 5 to 20 minutes.
  • About 95 percent of dreams are forgotten.
  • Most people have between 4 to 6 dreams each night.
  • On average, you’ll have about 6 REM cycles during an 8-hour sleep.
  • Some people dream in color, while others dream in black and white.
  • Those who became blind before the age of 5 generally don’t dream in pictures.
  • You can have dreams during any stage of sleep, but they’re most vivid during REM.
  • Even though the brainstem sends out nerve signals to help relax your muscles during REM sleep, you can still experience body movement.

Many dreams are one-and-dones, but some are recurring. Studies show that certain dreams are universal and may symbolize hidden emotions or thoughts. Some common recurring dreams include:

  • falling
  • being chased
  • flying
  • being in an accident
  • running late

If you’re aware you’re dreaming while you’re dreaming, you’re having a lucid dream. Remember the panic-inducing movie masterpiece that was Inception? It’s kinda like that. Here are some theories as to why dreams exist in the first place.

Creative inspiration

Artists often say their best ideas come to them in dreams. When Mr. Sandman sprinkles some magic over your eyes, ideas that seem daft by day are brilliant at night. That’s because dreaming ignites creativity.

Logic is inhibited and visual imagery breaks away from reality like a Salvador Dalí painting.

Memory aids

How dreams affect memory storage isn’t entirely understood. However, some research supports the idea that dreams filter unnecessary memories while keeping track of what’s important.

Sleeping can help you retain new information. That’s why it’s always best to get a good night’s sleep while studying. Outside stimuli which would normally interfere with memory retention are ignored.

Fight-or-flight nurturing

The amygdala — an area of the brain associated with survival instincts — is one of the most active parts of the brain during sleep. Some research argues the amygdala is active during sleep because dreams prep you for real life threats.

Emotional processing

Dreams can help you process feelings. When you sleep, the brain functions on an emotional level. This allows you to analyze what’s going on differently than when you’re awake.

Have you ever had a dream so scary and powerful you woke up gasping? Remember, dreams help you process all emotions, not just the good ones. Nightmares are often triggered by:

  • trauma disorders, including post-traumatic stress disorder (PTSD)
  • stress or anxiety
  • illness
  • medication
  • alcohol or drug use and/or withdrawals
  • triggering stimuli before sleep (e.g. a horror movie or stalking your ex’s Instagram feed)

While the occasional nightmare is nothing to fear, recurring nightmares may indicate a sleeping disorder. Any sleep disorder that alters your sleep pattern puts you at risk of nightmares. Common disorders include:

  • insomnia
  • sleep apnea
  • restless leg syndrome (RLS)
  • narcolepsy

Some typical symptoms of sleep disorders are:

  • anxiety before bed
  • difficulty falling asleep
  • inability to sleep through the night

If you’re continuously struggling with nightmares and have difficulty sleeping, have a chat with your doctor. They can help you come up with the best course of action to deal with the issues at hand.

Wet dreams may seem like a distant tragic memory from your pubescent years, but they’re quite common in adults as well. In case you weren’t a Judy Blume fan or skipped health class in middle school, a wet dream is when you involuntarily orgasm in your sleep.

They often stem from erotic dreams, but that’s not always the case. Sometimes your sheets create a pleasant friction that hits you just the right way. Keep in mind:

  • Your junk is extra sensitive during sleep due to increased blood flow. That’s why morning wood is a thing.
  • While men are more commonly affected by snoregasms, women can have orgasms while sleeping too.
  • Not all erotic dreams end with actual orgasms.
  • Wet dreams are totally normal and nothing to be ashamed of!

Lots of factors influence our dreams. Some are serious and some are silly, but all of them can cause outrageous images.

Nom noms

Research shows unhealthy diets are often linked to poor sleep quality. Foods that affect you in your waking hours also impact you while you sleep.

Substances that affect energy levels — like sugar, caffeine, and simple carbs — may result in a messed up sleep cycle and whacky dreams. And while there’s no shame in the midnight snack game, eating before bed can disrupt your ability to rest.

Work it out

One of the best ways to slay those REM cycles at night is by exercising in the morning. A good cardio routine can help your body burn off energy in the beginning of the day.

This way, you’re more likely to fall asleep faster at bedtime. Additionally, exercise raises endorphin levels, which can ease anxiety. Studies show a clear mind can lead to a sounder sleep.

Health

Your health can change the intensity of your dreams. You’re more likely to have vivid dreams if you’re sleep deprived, since certain parts of the brain are more active when you finally do hit the hay.

Certain mental health disorders and mood-related conditions can also cause intense dreams. In fact, up to 71 percent of those with PTSD experience recurring nightmares.

Other causes may include anxiety disorders, depression, and bipolar disorder. Certain medications that treat these conditions — like antipsychotics and/or antidepressants — are also linked to nightmares or inexplicable dreams.

John Lennon once sang, “You may say I’m a dreamer, but I’m not the only one.” He was spot on, because every single human dreams every single night.

So, if someone tells you they don’t dream, they’re wrong. They just don’t remember them.

There’s a reason why you can’t remember all of your dreams. Norepinephrine — a chemical associated with memory — is at its lowest level when you dream.

The brain’s electrical activity, which aids in memory retention, also slows down. That’s why, unless you wake up mid-dream, you won’t remember bathing in a tub of mac and cheese or whatever other crazy thing your subconscious came up with.

If you want to remember your dreams, the trick is to write them down while you still remember them. It’s very easy to forget a dream once you’re fully awake.

Also, if you tell yourself, “I will remember my dreams when I wake up,” you’re more likely to recall them. So keep a notepad by your bed, or start a log in your phone or computer. Jot it down before it slips away.