 Hey everybody, Dr. O here. In this video I want to go a little bit deeper into the cerebellum. We talked about it in our brain overview, but the cerebellum is the second largest part of our brain. The name basically means little brain there. As you can see it has white matter on the inside, gray matter on the outside, just like your cerebrum. What you see there is actually called the arborvitae or tree of life because it does kind of look like a tree with a bunch of branches. So the primary functions of the cerebellum would be, number one, to adjust and control the postural muscles of your body. So like if you're positioning yourself or you're sitting, you're standing, these types of things, the cerebellum is constantly making adjustments with those postural muscles, subconscious adjustments. And number two, the most important one is programming and then fine-tuning movements, whether they're controlled at the conscious or subconscious level. So the fact that when I go to reach for this coffee, I can do it smoothly, has to do with the cerebellum and that takes practice, right? When you and I were babies, we couldn't reach for anything and if we tried, we'd miss and we wouldn't be able to control it. Well, over time, your cerebellum continues to fine-tune movements and you get better and better at them the more you practice it, right? This idea of muscle memory. But the reason that's important, I would say if your cerebellum is not functioning properly, your brain actually likes to send too much, your cerebrum, sorry, likes to send too much information to your muscles. The cerebellum kind of taps the brakes and that's how you smooth movements out. So for me to do something as simple as grabbing a cup of coffee, there could be 40 or 50 muscles involved, right? Walking isn't going to involve hundreds of different muscles and you need some to be turned on, some to be turned off, right? It actually is very complex. We just kind of make it look easy and the cerebellum is what does that. All right, let's look at a few things here. So one thing I find fascinating inside the cerebellum, we have these special cells called Purkinje cells. They're highly branched and they actually can have as many as 200,000 synapses. So one cell can form connections with up to 200,000 other structures. Pretty amazing. It shows you how much information the cerebellum is receiving and sending out. So you see the cerebellar peduncles, you have the superior peduncle, inferior peduncle and middle peduncle there. Well, they're going to be the tracks that carry information to and from the cerebellum, the brainstem and the spinal cord. So balance, posture, coordination is where the cerebellum is responsible for. I always like to say nerves that fire together, wire together. So the reason we practice things is you basically want them to become reflexes. That's kind of how I look at it. Like you can practice something and your cerebellum can fine tune a movement so much that it almost becomes a reflex, like not by definition. But you know what I mean? Like if you're, whether maybe you're into video games or playing an instrument, when you first started doing things, simple controls of video game controllers, playing guitar, things were very complicated, took a lot of conscious thought. My stepson is really good at playing guitar. And now he just sits down and plays the guitar, right? He just does it. Or athletes, like some of the best hitters in the history of baseball aren't really good at coaching or teaching people how to do it because what do they do? They see the ball and they hit it. But by the time a baseball player has reached Major League Baseball, they've swung a baseball bat between one and four million times. So they've turned it into a reflex. Their cerebellum is so fine tuned that they just see the ball and hit it. They don't have to consciously think about it. And that's great because you can't, you know, it takes too long. So we can actually learn movements so well and build a muscle memory so well that things that used to take a lot of conscious effort now take little or none. So I actually remember, I think it was a Yale professor proved it's physically impossible to hit a 95 mile an hour fastball, which obviously they can do. But what he meant was in the time it takes that pitcher to throw the ball, you have to find the ball, you have to track it out of the pitcher's hand, you have to determine what type of pitch it is, determine if it's going to be a ball or strike, and then determine if you're going to swing. And then you got to swing and hit a round ball with a round bat squarely, right? Well, it's impossible to do all those things consciously in 0.4 seconds, whatever amount of time you have, but your cerebellum can kind of take over these types of things. That's why I'm fascinated by the cerebellum. This idea of practicing, practice making perfect and this idea of muscle memory was the cerebellum fine tuning all these processes that allows it to happen. Now on the flip side, what happens if your cerebellum isn't working well? Damage to the cerebellum or alcohol intoxication can lead to what's called cerebellar ataxia, which affects your ability of muscle coordination. So even a major league baseball player is going to have a hard time hitting a baseball if they're drunk and that's because the cerebellum can't function properly. That's what a field sobriety test is for. It's actually trying to diagnose you in a sense with cerebellar ataxia. If you can't walk a line, you can't touch your fingers to your nose, all that kind of stuff, then that means your cerebellum is not working. Now, does it mean you're drunk? No, you could have some sort of brain damage or damage to the cerebellum, but generally that's what it means. Okay, so that's a little bit more information, kind of some interesting stuff about the cerebellum and how it works and why it's so important. I hope this helps. Have a wonderful day. Be blessed.