7 Fun Brain Facts That Will Blow Your Mind

Amazing Fun Brain Facts for Kids

Hey, kids! Get ready to learn lots of fun facts about your amazing brain!

Amazing Facts About Your Brain, the Boss of Your Body

Your brain can do so many things whether or not you notice. That’s because the human brain is powerful. It controls every single thing in your body.

It lets you think and blink, rest and digest, move and groove, and much more.

Although your brain gives you unique ideas and personalities, your brain also has a lot in common with other human brains.

Amazing facts about the human brain for kids

Keep reading to learn about interesting brain facts. Then share with your friends at school or family at home!

Fun fact #1: Human brains are wrinkly but start smooth.

The normal human brain is crinkled with lots of hills and valleys. But it wasn’t always this way.

Before you were born, you were a tiny fetus. When you were a fetus, your brain was smooth at first.

As your brain grew during pregnancy, your brain gradually began to fold and looked wrinkled.

Why is the folding process so important? More brain tissue can fit into the skull. Folding also separates your brain into different sections, and it helps each part of your brain work properly.

Check out this 3-D gel model of a fetal brain from a lab at Harvard University. It shows how a brain might grow and fold.

Fun fact #2: Your eyes are like windows to your brain.

Brain anatomy connected to eye by optic nerve

You can learn so much about someone just by looking at the eyes. That’s because the long optic nerves connect the brain to the back of each eyeball. Plus, the back of the eye – the retina – is made of brain tissue.

Pupils – the opening in the middle of your eyes – get wider when you get excited or scared. On the other hand, pupils return to their regular, smaller size during relaxation, such as during a mindfulness activity.

Doctors also use a special magnifying glass to look through the pupils at the retina and optic nerve at the back of the eye.

For example, if the retina’s blood vessels have problems, there might be problems with the brain’s blood vessels.

Fun fact #3: A baby’s brain weighs less than 1 pound.

Have you noticed that a baby’s head looks big compared to the body?

Even though the head looks relatively big, the newborn brain weighs less than 1 pound (0.5 kilograms). This is one of the coolest facts about the brain!

After a baby is born, the neck is not yet strong enough to hold up that big head. Grown-ups must carefully support a baby’s head and carry them around until the baby grows stronger.

Amazing fact: A baby's brain weighs less than 1 pound (0.5 kilograms).

Fun fact #4: It keeps developing until age 25.

The human brain does most of its growing during the toddler years. By the time a kid is five years old, the brain is almost the size of the adult brain.

But that’s just part of the beginning!

During the childhood and teenage years, the human brain grows more gradually as it absorbs tons of information.

Around age 25, the brain is fully formed and weighs around 3 pounds (1.3 kilograms). It’s heavier than other human organs like the liver, spleen, and lungs. This amazing brain fact surprises a lot of people!

Humans can legally drive and vote before their brain is fully developed.

fun fact: your amazing brain inside the skull keeps developing until age 25

Fun fact #5: Nerve cells talk to each other.

Your brain is made of billions of nerve cells called neurons. Because neurons are so small, you must use a microscope to see them. Under a microscope, they look like little trees with branches and roots.

neuron axon

This fun brain fact is all about teamwork. Neurons need to communicate to work together. Neurons talk to each other by sending important signals called neurotransmitters.

Because your brain has various jobs, like thinking, remembering, and feeling emotions, it has many different neurotransmitters. More than 100, actually!

Have you ever heard of dopamine? This neurotransmitter is famous for making us feel good after we do something rewarding. Exercising, getting good sleep, and playing outside are great ways to boost your body’s dopamine levels.

Fun fact #6: It has a bridge.

This fun brain fact is extra important. Did you know that nerves are a bunch of neurons (nerve cells) bundled together? You can see them without a microscope.

The corpus callosum is a special nerve bundle that acts like a bridge in your brain. But why does your brain need a bridge?

Fun brain fact: It has a bridge that connects each half together.

When you look at a human brain, it looks like it has been cut in half.

Without the corpus callosum bridge, the left half and right half of the brain wouldn’t be able to communicate and work together.

Fun fact #7: You can slow down shrinking.

Like any body part, the brain ages. Although this brain fact is not so fun for older people, it’s a part of life. Around age 40, the human brain starts to shrink as it loses some cells and the connections between cells.

Good news: You can slow down the brain shrinking process. Whew!

Exercising, eating healthy, sleeping well, and spending time with friends can help keep your brain as sharp as possible.

Learn more about your amazing body!

These fun facts about your brain work with other important organs. What do you want to learn more about?

Human Body Learning has strict sourcing guidelines and relies on information from peer-reviewed research studies, academic institutions, and medical associations.

Published on November 29, 2023. Updated on January 18, 2024 by Betty Choi, MD

Published on November 29, 2023. Updated on January 18, 2024 by Betty Choi, MD

Dr. Betty Choi pediatrician

Betty Choi, MD

Dr. Betty Choi is a Harvard-trained pediatrician who makes learning fun and doable. She created the kids’ anatomy book Human Body Learning Lab, which Science Magazine recommended as a “notable standout in the genre.”