How The Brain Works

Part of the NerdBeach Series “How the Human Body Works”

Let’s take a moment to appreciate one of the strangest and most impressive things in the known universe: Your brain.

It weighs only a few pounds, looks vaguely like a wrinkled blob someone forgot in the fridge, and yet somehow manages to control your thoughts, movements, memories, emotions, personality, and your ability to remember embarrassing things from seventh grade at 2 AM.

Honestly, it’s ridiculous. The human brain is the command center of your entire body – a biological supercomputer so advanced that even modern technology still struggles to replicate what it does naturally every single day.

And the weirdest part? Most of us walk around using one constantly without fully understanding how it works.

So let’s break down exactly what your brain is doing up there inside your skull and why it’s one of the most fascinating machines ever created.

The Brain Is Basically Mission Control

• Brain’s Function: Controls everything the body does, both consciously and unconsciously.
• Involuntary Actions: Manages automatic functions like breathing, heart rate, and digestion.
• Multitasking Ability: Simultaneously handles background systems and conscious thought.

At its simplest, the brain controls everything your body does. And I mean everything.

Breathing? Brain.
Walking? Brain.
Talking? Brain.
Wondering if you left the stove on after already leaving the house? Also brain.

It manages both the things you actively think about and the things you never think about at all.

Your heart beating? Automatic.
Your lungs breathing? Automatic.
Digesting lunch while you’re busy watching YouTube? Also automatic.

The brain is constantly running systems in the background while somehow still making room for conscious thought. It’s multitasking at a level no office employee could ever hope to achieve.

Neurons: The Brain’s Tiny Messengers

• Brain Function: The brain works through specialized cells called neurons that communicate using electrical and chemical signals.
• Neuron Communication: Neurons constantly send signals to one another, enabling the brain to control bodily functions, process information, and generate thoughts and memories.
• Neuron Quantity: The human brain contains roughly 86 billion neurons.

Your brain works through specialized cells called neurons. Think of neurons like microscopic messengers. Your brain contains roughly 86 billion of them, all constantly sending signals to one another.

That’s right – your skull is basically housing an entire civilization of tiny cells shouting information at each other nonstop. Neurons communicate using electrical and chemical signals, rapidly passing messages across the brain and body. This is how your brain says things like:

• “Move your hand.”
• “That stove is hot.”
• “Remember that song lyric from 2007 for no reason whatsoever.”

They fire constantly, often at incredible speeds, keeping your body and mind functioning in real time.

Different Parts Handle Different Jobs

• Brain Function Specialization: Different brain regions specialize in different tasks, similar to departments in an office building.
• Frontal Lobe Functions: Decision-making, planning, personality, and problem-solving.
• Other Lobe Functions: Parietal lobe processes touch and spatial awareness; temporal lobe helps with memory and language; occipital lobe handles vision.

Your brain isn’t just one giant lump doing everything equally. Different regions specialize in different tasks. For example:

The frontal lobe helps with decision-making, planning, personality, and problem-solving.

The parietal lobe processes touch and spatial awareness.

The temporal lobe helps with memory and understanding language.

The occipital lobe handles vision.

It’s like a giant office building where every department has its own job. Except instead of filing paperwork, they’re handling reality itself.

Your Brain Runs on Electricity

• Brain Function: Neurons send electrical impulses to one another to generate thoughts, movements, and sensations.
• Signal Speed: Electrical signals in the brain move extremely fast, enabling rapid reactions to stimuli.
• Robotic Nature: The electrical basis of brain function makes humans function in a way that is similar to robots.

Here’s something delightfully unsettling: Your brain is partially electrical. Every thought, movement, and sensation happens because neurons send tiny electrical impulses to one another. So technically speaking, your brain is constantly zapping itself in order to function.

Which makes humans sound slightly more robotic than most people realize.

These electrical signals move incredibly fast, allowing you to react to things almost instantly. Touch something hot? Your brain receives that signal and responds before you even consciously think: “Wow, this was a poor decision.”

Memory Is Basically Organized Filing…Sort Of

• Memory Formation: Memories are stored by creating patterns and strengthening neural connections through repetition and experience.
• Memory Prioritization: The brain prioritizes information based on repetition, emotional importance, and usefulness.
• Memory Limitations: The brain’s prioritization system can lead to forgetting important information while retaining trivial details.

Your brain stores memories by creating patterns and strengthening neural connections. The more you repeat or experience something, the stronger those connections become. That’s why:

• You can remember song lyrics from twenty years ago
• But forget why you walked into the kitchen five seconds ago

Your brain prioritizes information based on repetition, emotional importance, and usefulness. Unfortunately, it sometimes decides:
“Traumatic middle-school embarrassment? Save forever.”
“Important password? Absolutely not.”

Brains are powerful, but not always logical.

Your Brain Never Actually Stops Working

• Brain Activity During Sleep: Processes memories, organizes information, and repairs itself.
• Dream Function: Scientists understand some aspects of dreaming but not the full reason for nonsensical dream scenarios.

Even when you’re asleep, your brain is still active. Very active. While you sleep, your brain:

• Processes memories
• Organizes information
• Repairs itself
• Runs dreams that make absolutely no sense

Dreams, in particular, are still somewhat mysterious. Scientists understand some aspects of dreaming, but we still don’t fully know why your brain occasionally creates scenarios where you’re suddenly late for school despite not being in school for fifteen years.

Brains are weird like that.

The Brain Uses a Massive Amount of Energy

• Brain Energy Consumption: The brain uses about 20% of the body’s energy despite being only 2% of its weight.
• Reason for High Energy Use: The constant activity of billions of neurons requires a significant amount of energy.
• Calorie Burn from Thinking: Thinking does burn calories, but not enough to replace exercise.

Despite only being about 2% of your body weight, your brain uses around 20% of your body’s energy. That means this squishy thought-machine is wildly power-hungry. Why?

Because running billions of neurons constantly takes enormous effort. So yes, technically thinking burns calories. Not enough to skip exercise. But still.

Emotions Come From Chemical Chaos

• Neurotransmitters and Emotions: Neurotransmitters are chemicals that heavily influence emotions, regulating mood, motivation, happiness, and stress.
• Examples of Neurotransmitters: Dopamine (reward and motivation), serotonin (mood regulation), and adrenaline (preparation for danger).
• Emotional Regulation: Much of emotional life is the brain mixing chemicals to influence emotions.

Your emotions are heavily influenced by chemicals called neurotransmitters. These chemicals help regulate mood, motivation, happiness, and stress. For example:

• Dopamine helps with reward and motivation
• Serotonin helps regulate mood
• Adrenaline prepares you for danger

Basically, much of your emotional life is your brain mixing chemicals together and hoping for the best. Which honestly explains a lot.

Your Brain Is Constantly Rewiring Itself

• Neuroplasticity Definition: The brain’s ability to adapt and reorganize itself over time.
• Brain Changes: Learning, practicing skills, and experiencing new things physically change the brain by strengthening certain pathways.

One of the coolest things about the brain is neuroplasticity. That means your brain can adapt and reorganize itself over time. When you learn something new, practice a skill, or experience new things, your brain physically changes by strengthening certain pathways.

So every time you:

• Learn an instrument
• Practice a hobby
• Gain new knowledge

Your brain is literally rewiring itself. Which is incredibly cool and mildly terrifying.

The Brain Is Still Full of Mysteries

• Brain Complexity: Scientists still don’t fully understand the brain despite knowing a lot about it.
• Unexplained Phenomena: The reasons for consciousness, dreams, and memory are not fully understood.

Here’s the wildest part: Despite everything we know, scientists still don’t fully understand the brain. We know a lot. But many mysteries remain:

• Why consciousness exists
• Why dreams happen exactly
• How memory truly works in full detail
• Why brains randomly remember cringe moments forever

Even modern science admits:
“This thing is unbelievably complicated.”

Your Brain Is Kind of Amazing

The next time you stop to think – literally – remember what’s happening behind the scenes.

Your brain is:

• Running your body
• Processing information
• Managing emotions
• Storing memories
• Keeping you alive
• And somehow allowing you to read this article while maybe also thinking about snacks

All at the same time. It’s one of the most advanced biological machines ever discovered. A weird, electric, emotional, memory-hoarding supercomputer sitting inside your head.

And somehow? It mostly works. Which, given how absurdly complex it is, might be the most impressive part of all.

This article is part of the NerdBeach series: How The Human Body Works