Why do we dream? The Mystery Your Brain Creates Every Night

I’ve had dreams where I was flying, being chased by dinosaurs, talking to celebrities, earning millions, and living a life one can only dream of.

None of it made any sense.

Yet while I was dreaming, it all felt completely real.

Every time we humans sleep, our brain decides to become a Hollywood director. Unfortunately… it isn’t very good at writing scripts. From the scariest nightmares, where all our fears come to life, to the happiest moments we wish were real, everything seems possible in our dreams.

But have you ever wondered how and why our brain creates this strange virtual reality? And do our thoughts influence the kind of dreams we have?

Well… it’s time to understand why our brain becomes so creative only after we fall asleep.

As you begin to fall asleep, your brain enters Stage 1, the light sleep stage. During this stage, your prefrontal cortex begins to slow down, and you may experience brief hallucinations like flashes of light, vivid shapes, or even the strange sensation of falling.

This is followed by Stage 2, often called deeper light sleep. During this period, your brain produces short, dream-like thoughts or memories that still make logical sense. Surprisingly, this stage makes up more than half of your sleep.

Next comes Stage 3, also known as deep sleep. Your body is now fully relaxed, making it difficult to wake you up. Dreams are rare during this stage, and if they do occur, they’re usually fragmented and unclear.

Finally comes the stage where your brain truly becomes a movie director, REM (Rapid Eye Movement) sleep. During REM, your brain is almost as active as when you’re awake. Your eyes move rapidly beneath your eyelids, and this is where the vivid, bizarre dreams we all know begin. The craziest part? These stages don’t happen just once; they repeat 4 to 6 times every night where each REM stage becomes longer than the previous one.

While REM sleep might seem peaceful from the outside, inside your head it’s a completely different story. Different parts of your brain begin working together to build an entire world that feels surprisingly real.

First, the pons in your brainstem temporarily paralyses your body. Most of your muscles stop working so that you cannot physically act out your dreams and accidentally hurt yourself. During this stage, your heart rate and blood pressure also become unpredictable.

The thalamus acts like a movie projector. It blocks out most of the external stimuli, like someone snoring beside you and instead sends internally generated images and sounds to your conscious mind. Side by side, the amygdala, which is the emotional centre of your brain, acts as an emotional booster, which is why dreams can feel intensely depressing, exciting, or even terrifying.

So, how are you able to see while your eyes are closed? That’s where the visual cortex comes in. This part of the brain becomes highly active as soon as you enter REM sleep, creating all the vivid images and scenes you experience in your dreams.

Meanwhile, your prefrontal cortex (located just behind your forehead) becomes much less active. This part of the brain is responsible for logic, decision-making, and time awareness. That’s exactly why our dreams are so illogical, weird, and strange. Flying through the sky, talking to dinosaurs, or watching your maths teacher dance on stage somehow feels completely normal.

But dreams aren’t created out of thin air. Every dream needs some kind of story. Well, that’s the job of the hippocampus. This part of your brain acts like a giant memory library, storing moments from your life and using them whenever needed. During REM sleep randomly puts these memories together, that’s why you might dream about your childhood home, your best friend, and a movie you watched last week all in the same dream.

Photo by ian dooley on Unsplash

But your dreams aren’t influenced only by old memories. The thoughts and emotions you have experienced during the day also play vital role. If you’ve been worried about an upcoming exam lately, chances are you will end up dreaming about reaching school late or forgetting everything you studied. Scientists call this the Continuity Hypothesis, which suggests that our dreams are simply an extension of our waking life. Our brain takes our thoughts, memories and emotions and mixes them into one of the most bizarre stories.

But man… why do we dream? Bro, just let me sleep.

Well, believe it or not, your brain is trying to help you. It’s the good guy here.

While we sleep, the levels of stress chemicals in our brain drop significantly. This allows our brain to replay stressful events without making us feel the same emotional intensity we experienced while we were awake. Think of it as your brain slowly washing away the emotional sting you’re holding onto.

Your brain also likes to put you through little “threat simulations.” That’s why so many dreams involve being chased, falling, or trying to escape from something. Scientists believe these dreams may mentally prepare us to deal with real-life challenges. (Although I highly doubt being chased by a dinosaur will ever be one of them.)

The human brain is undoubtedly one of the most fascinating things in the universe. Every single night, it creates a world so realistic that, for a few hours, we completely believe it.

So tonight, when you close your eyes and doze off, don’t be surprised if you find yourself back on that stage… standing beside your dancing maths teacher while dinosaurs chase your favourite celebrity. That’s just your brain doing what it does best.