Why Do We Dream & Why We Forget? What Happens Inside Your Brain While You Sleep

[00:00:00]Every night your brain creates a world that feels completely real. You can talk to people who aren't there, visit places you've never been, relive old memories, feel fear, excitement, and sadness.

[00:00:14]And while all of this is happening, your body hasn't moved at all. You are still in your bed, asleep. So, what exactly is a dream? Why does our brain create them?

[00:00:25]Why do they feel so real? And why do we forget almost the moment we wake up? In this video, we are going to explore this.

[00:00:34]So, the first question is, what are dreams?

[00:00:38]The answer is pretty simple.

[00:00:41]A dream is simply an experience that looks and feels exactly like when you are awake, but it is created by your own brain while you're asleep.

[00:00:49]Instead of taking information from the outside world, your brain starts generating its own sights, sounds, emotions, and stories. That's why dreams can feel like watching a movie, except you're inside it. Most clear and lucid dreams happen during a stage of sleep called REM sleep, where brain activity becomes surprisingly similar to when we're awake. And probably you have a question in your mind.

[00:01:12]What is this REM sleep? In order to answer that, we need to know categories of sleep. There are two categories of sleep. One is non-REM or NREM sleep, and the other is REM sleep. The word REM stands for rapid eye movement. The normal sleep cycle lasts roughly 90 to 110 minutes and repeats four to six times per night. The sleep cycle always starts with the NREM cycle, and it takes the first half of the night or early sleep, moving from stage one to stage three. And after that, REM sleep starts, which takes the second half of the night or early morning sleep. The non-REM sleep can be even further divided into N1, N2, and N3 stages. The N1 stage is very short, which only takes 1 to 7 minutes, and in that period, we feel hallucinations.

[00:01:59]You also have noticed this thing. When you were just starting to fall asleep, you hear someone calling your name, and suddenly you wake up. This is common in this phase.

[00:02:07]In the N2 stage, our mind starts to enter deep sleep. It starts to stop all our sensory units, and this phase lasts for 10 to 25 minutes.

[00:02:15]>> In the N3 phase, which takes 20 to 40 minutes, the mind enters deep sleep. At that time, you have no consciousness.

[00:02:23]And if someone tries to wake you up in that state, you feel very foggy, and you don't even understand what is happening around you for a few minutes.

[00:02:31]>> But, the most interesting phase is REM sleep, which lasts for 30 to 60 minutes in the early morning. In this phase, the mind undergoes an explosion of emotional activity. The brain starts creating highly vivid, narrative, emotional, and visual dream spaces.

[00:02:47]Sometimes, during this state, the parts of our brain responsible for self-awareness and logic unexpectedly wake up, even though we are asleep. That time, we can realize, "Oh, wait, this is a dream." And sometimes even control what happens next.

[00:03:01]From all of this, we get one question.

[00:03:03]Why do we dream?

[00:03:05]This is probably the biggest question, and the honest answer is we still don't know for sure.

[00:03:11]But, some researchers and scientists think that dreams are closely connected to how the brain processes emotions, organizes memories, and makes sense of recent experiences.

[00:03:21]Think about it. You completed the day and went to sleep, and you started seeing things. That time, your brain isn't replaying memories like a video recording. It's combining pieces of memories together and putting them in a storage room.

[00:03:35]Isn't that exciting?

[00:03:36]So, how does the brain create a dream?

[00:03:40]Dreams aren't created by one single part of the brain. They're the result of several systems working together.

[00:03:46]While we are asleep, our brain disconnects from most of the outside world and starts creating its own. It takes bits and pieces of your memories, familiar face, a place you visited, a conversation you had yesterday, and mixes them to make a new story.

[00:04:00]At the same time, the part of the brain which creates emotion remains highly active. But the interesting fact is that the part which asks logical questions becomes inactive or quiet. That means our brain doesn't question the impossible things, like our home instantly becoming our college classroom. You might even be flying through the sky, and it all feels perfectly normal. Because the brain never questions it, that's why dreams feel so real. The same organs that help us see, hear, and experience emotions when we are awake are still active. The only difference is that they're no longer responding to the outside world.

[00:04:35]They're responding to a world our own brain is creating.

[00:04:38]Think about a nightmare, where we have dreamed that we are falling off a building.

[00:04:42]Just before we hit the ground, we suddenly wake up with our heart pounding and breathing heavily.

[00:04:49]For a few seconds, it feels like that was real.

[00:04:52]That's because according to our brain, we fell. In that time, our brain isn't simply imagining, it is simulating a story.

[00:05:00]And then, why do we forget dreams?

[00:05:03]This could be something surprising, because most people dream several times every single night, yet we wake up remembering almost none of them.

[00:05:11]Why?

[00:05:12]Because while we are dreaming, our brain isn't in a great state to save those experiences as long-term memories. The chemicals normally needed to save a memory are much less active during sleep.

[00:05:23]And that's not all. Researchers have found that the brain also has a way to clear away this dream information before we fully wake up.

[00:05:30]It's almost like deleting temporary files from a computer to make space for new ones.

[00:05:35]After this, reality takes over. The alarm goes off, check our phone, and we start thinking about college, work, and other things.

[00:05:43]Within seconds, those new thoughts replace the temporary memory of the dream, and we completely forget about them.

[00:05:50]So, next time you wake up thinking, "I was just dreaming.

[00:05:53]What was it?"

[00:05:55]Don't blame yourself.

[00:05:56]Instead, think, "That was one of the strongest signs that your brain is working exactly as it should."