Braaains!

How much thought have you really given to the incredible organ that's atop your shoulders, you know, the very thing that's allowing you to understand these words> So that you might take a moment to consider the utterly amazing organ keeping everything about you, alive?

Human brain anatomical diagram. Courtesy of the Mayfield Clinic, via Wikimedia Commons

When you think about it, the brain is more than just the most important organ in your

body, it's roughly three pounds that controls all the body's various functions, but it interprets information from the outside world derived through your many senses. But for some, it also is where the soul "lives". Memory, creativity, speech, balance, digestion, breathing, heart rate, it's all controlled by something no bigger than your fists held together, gently floating in your skull, however thick your parents told you it was ;-) While the brain has many parts to it, some smaller than your pinky fingernail, today we'll focus on the "big 3": the cerebrum, cerebellum, and the brainstem.

We'll start with the biggest part, the Cerebrum. Real quick, make two fists and put them together so your thumbs are touching. ROUGHLY SPEAKING, you're looking at the size of your brain. Like your two hands, you're probably aware that your brain is divided into both halves or hemispheres and that they're responsible for doing different things AND that they're connected. That connection is called the corpus callosum. This roughly 10 cm bundle of nerve fibers allows messages to be sent back and forth but strangely enough, the right hemisphere controls the left side of your body and vice versa. This is why when someone suffers a stroke in the right side of their brain, the left side of their body may become partially paralyzed or weakened. Your cerebrum also contains the portion of your brain responsible for short-and-long-term memory.

For example, when I was in 6th grade, I was fortunate enough to be part of a student-exchange program. That was June of 1992 and more incredibly, I celebrated my birthday in Nice, France! I remember this so vividly not because I turned 12 in another country, but because I was sitting on beach, eating lunch, not dealing well with a sunburn from the day before and the oddly-remembered detail is that I was wearing a purple baseball hat.

But it is also why you can remember what you had for dinner two nights ago (pork carnitas tacos and margaritas for me). You cerebrum also allows you to process what your eyes are telling, allows you to groove out to your favorite song, draw a picture or solve that math problem. So, let's put your cerebrum to the test with some simple riddles... Answers will be at the bottom of the page. NO PEEKING!

The Hobbit cover, artist, J. R. R. Tolkien. Image courtesy Wikimedia Commons

1. The more you take, the more you leave behind. What am I?

2. David's father has three sons: Snap, Crackle and _____?

3. What has roots nobody sees, is taller than trees. Up, up it goes, and yet never grows? (This riddle is from The Hobbit)

4. You live in a one-story house made entirely of redwood. What color would the stairs be?

5. What is as light as a feather, yet no one can hold it for long.

Any luck figuring them out? That's okay, the answers are waiting for you at the end of the post.

The next part of the brain is your cerebellum (Latin for "little brain"). Towards the back of your brain and below the cerebrum hides a very important part of your brain. Although smaller than your cerebrum, without this part of your brain, life would be very different. This next part is going to sound a little ridiculous, but bear with me. If you've ever moved any part of your body, you've used your cerebellum. Chasing down that soccer ball, riding your bicycle, surfing or even simply just standing up straight. Yup, you can use all the skills you have to do these activities but without the cerebellum, none of this would be possible. Your cerebellum controls balance, movement, and coordination. Like your using your cerebrum and your memory to recall everything about your last trip, we can put your cerebellum to the test.

Follow these steps and you'll see just how "in charge" your cerebellum really is.

1. Stand on your right foot.

2. Use your right hand to pat the top of your head.

3. Now, use your left hand to rub your stomach.

4. Without jumping, raise your right foot.

I know you can't complete that last step because if you COULD, you'd fall over. One of your cerebellum's primary job is to keep you upright. You stumble? Your inner ear and cerebellum work to ensure you don't fall.

Lastly is the brainstem. This connection to your spinal cord is actually made of three distinct parts: midbrain, the pons, and the medulla oblongata. But if you want to do more research into them, the Mayfield Brain & Spine's website is a great place to start... After you're done reading here of course. It's hard for me to decide which part of the brain is "the most important" but it doesn't get much more important than your brainstem.

For a minute, think of the things that are going on inside your body that you're not in control of: breathing, heart beating, digesting, sneezing, coughing, eventually your sleep cycles or thermoregulation (constant body temperature). Not only does this tiny part of your brain do ALL OF THAT but it also serves as the main connection of all your body's nerves and the cerebrum and cerebellum. From your toes telling your they're cold, to whatever's tickling your nose, or the feeling of a full bladder, it all passes through your brainstem to the part of the larger parts where that message is dealt with.

You can decide to hold your breath but eventually your brain stem overrides the conscious choice and forces the air from your lungs. Try it; pinch your nose closed and take a deep breath, hold it as long as you can. (Did you make it past 30 seconds?) You can't die from deciding to hold your breath, your brainstem won't let you. What about that sandwich you had for lunch? You didn't tell your stomach and intestines to release acid and absorb the nutrients (respectively) but there it is, digested food. You may be able to hold your urine back while on a long car trip but eventually, your bladder WILL empty itself, whether you're in that car or in a bathroom. Take your pulse and then run in-place for 60 seconds and undoubtedly, your heart rate will jump to accommodate the increase in oxygen demand from your muscles. All these actions are due to that precious brain stem of yours.

The most important human organ? Image courtesy of Wikimedia Commons

There are many more parts of the brain like the pituitary gland or the hypothalamus, the occipital lobe and amygdala. Far too much to get into here but let your curiosity lead your way and you might be surprised about exactly what your brain is capable of and what it does without your permission.

One last thing as promised, here are your riddle answers:

1. Footsteps

2. David

3. A mountain

4. What stairs? (You live in a one-story house.)

5. Your breath

Now that you've had some time to exercise this incredible organ here, check out the other links throughout this post and go learn some more! The other parts of the brain are almost incredible as the three major ones discussed here. You never know what you might find that interests you... Just food for thought ;-)