In the time it takes you to read these first few paragraphs, your heart will pump about five litres of blood. It sounds like a lot, but that’s nothing compared to the 30,000 to 40,000 skin cells you’ll shed in the same time period. Meanwhile, your eyes will blink around 12 times without you having to think about it, although maybe you’re starting to think about it now?
The human body is a marvellous feat of evolution, improved and reworked and rejigged over millions of years. Scientists still don’t know exactly when we became the humans that we recognise today1, but we do know that it’s our health that helps us realise every ounce of that hard-earned potential.
Take the human brain. We know it helps us think, and solve problems, and remember the lyrics to songs, but what else does it do every single day without our input? And how can we help it do it better?
Let’s take a moment to appreciate the incredible supercomputer that is the human brain, and say thanks.
It filters information at lightning speed
As you read this article, your brain is doing more than just making sense of the words on the screen. Not content with simply converting lines into letters and letters into words and words into sentences, your brain is keeping an eye on your surroundings, too. Whether you’re reading this on a computer at work or scrolling through it on your phone on the loo, your brain is right now absorbing and discarding information about your immediate environment. Maybe it’s the conversations of your colleagues nearby, or the slight vibrations of someone walking past.
Whatever they might be, there are myriad visual, tactile, olfactory and auditory stimuli competing for our attention at any given moment. Luckily for us, the human brain is capable of processing enormous amounts of data and deciding what’s worth paying attention to so that we don’t have to. This process is known as selective filtering or selective attention. Generally, our brains do it all the time. It’s how you’re able to focus on a single conversation in a crowded room. Your brain tunes out the unnecessary data (loud music, nearby movement) and helps you zero in on the information you need.
It regulates our temperature
Regulating body temperature is another of the brain’s core functions that doesn’t always get the kudos it deserves. We buy anti-perspirant deodorant to avoid sweaty underarms, and we hug our chests to stop ourselves from shivering, but those sweats and shakes are the brain’s way of cooling and heating our bodies for us.
As humans, it’s crucial to our physical health that our body temperature remains stable at 37 degrees Celsius. This is our body’s sweet spot: the temperature that allows it to perform all of the processes and functions we rely on to live well. When our temperature fluctuates, our brain steps in to correct it through a process called thermoregulation.
Sensory receptors on our skin detect our external environment—things like humidity, air-conditioning, or a cool summer’s breeze. The sensory receptors then relay this information via our nervous system to the hypothalamus in the brain. After receiving the information, the brain makes a call about whether the body needs to heat up or cool down to remain at 37 degrees. Pretty cool, right?
For example, if you’re too cold, your brain will automatically instruct the hairs on your arms to rise, allowing them to trap and store more heat. Or, if you’re too hot, your brain will instruct the body to sweat, causing you to lose heat and cool down.
So, the next time your laptop feels warm and the inbuilt fan starts to whir, or your smart phone switches off to cool down, just remember… your brain can do that, too.
It can store a lot of information
You’ve heard of a gigabyte, but what about a petabyte? Scientists believe the brain’s potential capacity for information storage is about 2.5 million gigabytes, or 2.5 petabytes. That’s about 1,125,899,906,842,624 bytes.2 Yep, really. Here’s why.
The human brain is made up of about 1 billion neurons. Each neuron forms approximately 1,000 connections to other neurons, which adds up to more than 1 trillion connections. When it comes to storing information and memories, neurons combine to exponentially increase those connections and the brain’s capacity for storage.
To put it another way, if your brain was a digital recording device, 2.5 petabytes would be enough to store something like 3 million hours of television. It would take almost 300 years of continuous recording to use up all that data.
Or to put it yet another way, that’s more memory power—much, much more—than the computer on board the Apollo 11 during the first moon landing.3 Your brain is literally out of this world.
Give your brain a break
The next time there’s a word on the tip of your tongue but you can’t quite get it, or (worse) you accidentally call someone by the wrong name, give your brain a break. Even when our minds feel slow and sluggish, remember: inside your skull, hard at work, is a supercomputer.