🔬 What Is the Brain?
The brain is the control center of the body. It's a soft, jelly-like organ protected by the skull and connected to the rest of the body through the spinal cord and a complex network of nerves.
It weighs about 1.3–1.4 kg (3 pounds) and contains around 86 billion neurons (nerve cells), which send and receive electrical and chemical signals.
🧭 Main Functions of the Brain
The brain controls:
-
Thinking & memory
-
Emotions
-
Speech & language
-
Movement
-
Breathing & heart rate
-
Vision, hearing, touch, taste, and smell
-
Decision-making & problem-solving
🧩 Main Parts of the Brain
| Part | Function |
|---|---|
| Cerebrum (largest part) | Thinking, memory, voluntary movement, speech |
| Cerebellum (at the back) | Balance, coordination, posture |
| Brainstem (connects brain to spinal cord) | Controls automatic functions: breathing, heartbeat, digestion |
| Limbic system (deep inside) | Emotions, motivation, long-term memory |
| Hypothalamus | Regulates body temperature, hunger, thirst, sleep, hormones |
| Amygdala | Processes fear, aggression, and emotional memory |
| Hippocampus | Essential for forming new memories |
⚡ How the Brain Communicates
The brain works through neurons, which communicate using:
-
Electrical impulses – send messages along neurons.
-
Neurotransmitters – chemical messengers that cross synapses (gaps between neurons).
Common neurotransmitters:
-
Dopamine – pleasure, reward
-
Serotonin – mood, sleep, appetite
-
Acetylcholine – memory, learning
-
Endorphins – pain relief, pleasure
-
Norepinephrine – alertness, stress response
🧠✨ Cool Brain Facts
| Fact | Info |
|---|---|
| 🧠 Brain energy use | Uses 20% of body's total energy, even at rest! |
| ⚡ Signal speed | Nerve impulses travel up to 430 km/h (270 mph) |
| 💡 No pain receptors | The brain can’t feel pain itself (brain surgery can be done awake) |
| 🛌 Dreams | Your brain is active all night — sometimes more than during the day! |
| 🔄 Neuroplasticity | The brain can rewire itself after injury or learning new things |
| 👶 Growth | A baby’s brain forms 1 million new connections per second in the first few years |
🏺 Interesting Historical Discoveries
| Person / Time | Contribution |
|---|---|
| Ancient Egyptians | Removed the brain during mummification, believed the heart was the seat of thought |
| Hippocrates (400 BCE) | First to say the brain controls thought and emotion |
| Galen (2nd century CE) | Studied brain anatomy using animals |
| Andreas Vesalius (1543) | Published detailed brain anatomy drawings |
| Phineas Gage (1848) | Survived a brain injury — changed personality; showed brain affects behavior |
| Wilder Penfield (20th century) | Mapped brain functions using electrical stimulation on live patients |
| MRI (1970s–present) | Revolutionized how we study the living brain in detail |
🧠🔍 Bonus: Brain Trivia
-
The brain generates about 25 watts of power—enough to power a light bulb!
-
The left side of your brain controls the right side of your body, and vice versa.
-
Your brain never “shuts off” — it’s active even while you sleep.
-
You can train your brain like a muscle — reading, learning, meditation help keep it healthy.