Riding a bike, crossing the street, typing a text message – as simple as these tasks seem, you can’t perform them unless your muscles are in perfect sync.
This coordination of muscle movement is one of the tasks of the cerebellum, a cauliflower-shaped area in the back of your brain.
Although relatively small, the cerebellum houses more than half of all the neurons in the brain. Due to its complexity, it has long been one of the most fascinating subjects of brain researchers around the world.
In this informative guide, we take a detailed look at the cerebellum and its primary functions. We also discuss some of the more interesting scientific findings about this mysterious part of the brain.
What Is The Exact Definition Of The Cerebellum?
The Oxford Companion to the Body defines the cerebellum as an “intricately corrugated ball of nervous tissue that lies under the rear end of the cerebral hemispheres and is attached to the brain stem by huge bundles of nerve fibers […] which carry information to and from other parts of the brain.”
This ball of tissue is located in the back of the head, between the cerebrum and the brain stem. One of the four main regions of the brain, the cerebellum takes up about one-tenth of the total brain volume.
The word cerebellum is Latin for little brain. It was first used more than 500 years ago by the great Renaissance artist, Leonardo da Vinci.
In 1504, while creating wax castings inside the human skull, DaVinci discovered two symmetrical brain hemispheres hidden just under the cerebrum. Because this newly discovered structure looked like a smaller sibling of the brain, he nicknamed it the little brain.
But DaVinci wasn’t the first to use the term.
In fact, the legendary Greek philosopher Aristotle used the Greek word paregkephalis in the fourth century to describe the same region of the brain that would, centuries later, become known as the cerebellum.
What Does The Cerebellum Do?
The cerebellum has many important functions, but is most notable for its coordination of muscle movement.
So, what does the cerebellum do and how does it work?
Every single voluntary movement we make starts as a signal that forms in the motor cortex of the cerebrum. This signal then travels to the cerebellum, which instructs the muscles to carry out the movement.
But the cerebellum is more than just an intermediary between the motor cortex and the muscles.
Before the movement signals reach the muscles, the cerebellum combines them with information about the current position of the body, which it receives from the spinal cord.
This allows for better coordination and enables your body to move in a smooth and balanced way.
How The Cerebellum Works In Real Life
To better understand how this process works, here is a practical example.
Let’s say you’re standing in your kitchen and want to grab a jar of honey from the top shelf. While the idea to reach for the honey is born in the cerebrum, there are several other things that need to take place to turn that idea into action.
First of all, you need to consider the current position of your body.
Then, your brain needs to make sure that all the muscles that will take part in this process are under control and ready to move as instructed.
In addition, your brain also needs to make adjustments to your movement as you go. This is not unlike an airplane flying from New York to Los Angeles. Although the course between the two cities is constant, the route is subject to change due to variables like weather and wind.
While you’re moving, your brain is also detecting errors and correcting them (very quickly) to ensure you perform your movement as planned.
In this example, it prevents you from reaching for the wrong shelf or accidentally grabbing the jam instead of the honey jar next to it.
All these functions – muscle coordination, body position awareness, and error detection and correction – are carried out by the cerebellum.
What Else Does The Cerebellum Do?
In addition to playing a crucial role in the coordination of muscle movement, the cerebellum has many other important functions. These include the following:
Maintaining physical balance and posture
The same way it detects and corrects errors in your movement, the cerebellum can detect shifts in your body’s balance. It then sends signals to motor neurons which instruct your body to readjust its posture to maintain balance.
The cerebellum also helps your body master movements that involve practice and fine-tuning in addition to physical skill. This process is called motor learning and refers to a wide range of movements – from breathing and walking to riding a bicycle or playing an instrument.
Eye movement control
In addition to controlling body movement and motor learning, the cerebellum is also important for your vision. Namely, it helps your brain take full control of voluntary eye movements, thus allowing for better eye-to-hand coordination. On top of that, the cerebellum plays a part in peripheral vision.
How Is The Cerebellum Different From Other Regions Of The Brain?
The cerebellum is one of the four main regions of the human brain.
The other three regions are: the cerebrum, the brain stem, and the diencephalon. Although they are interconnected, they differ in size, position, and the primary function that they perform.
It’s the part of the brain associated with thinking and other related processes. Primary cerebrum function includes speech, reasoning, problem-solving, memory, recognition, and perception of stimuli.
Because of their similar names, the cerebrum is often confused with the cerebellum. But when it comes to the cerebrum vs cerebellum debate, it’s important to know these two brain regions perform vastly different functions.
The cerebellum is in charge of the mechanical processes in the body. The cerebrum controls the thinking behind those processes.
Both are in charge of certain aspects of movement, which is another reason why some people tend to confuse them.
The Other Major Regions Of The Brain
Another major brain region is the diencephalon, the majority of which can only be seen by taking a cross-section of the brain.
The primary diencephalon function is directing sensory information and related impulses throughout the body. It also controls the autonomic, endocrine, and motor functions.
Finally, there is the brain stem, which is in charge of vital functions like breathing, circulation, and digestion. This region of the brain consists of two subregions – the pons and the medulla oblongata.
The pons is located in the upper part of the brain stem and plays an important part in the regulation of breathing. It holds the nerve cells that control your breathing volume and rate.
In addition, this brain stem function transmits signals between different parts of the brain and helps regulate deep sleep.
Working in tandem with the primary pons function is the medulla oblongata, which takes up the lower part of the brain stem. In addition to playing a role in breathing, proper medulla function helps maintain optimal blood pressure and heart rate. What’s more, the medulla is also in charge of involuntary actions like coughing and sneezing.
Does The Cerebellum Play A Role In Thinking?
Historically, scientists have thought of the cerebellum as the “unconscious” part of the brain that is only in charge of movement-related functions. This was in contrast with the “conscious” cerebrum, which is thought of as the center of all thinking-related activity in the brain.
However, recent research has challenged the idea of the “non-thinking” cerebellum.
A pioneering study published in 2004 argued that the cerebellum has the ability to fine-tune our thoughts in much the same way as it does our movement.
More than a decade later, a 2017 study found a link between structural variations in the cerebellum and the risk of mental disorders.
In addition, a 2012 review found that the cerebellum may play a role in mood and language processing, two brain functions commonly associated with the cerebrum. More recently, scientists have managed to identify the posterior lobe as the area of the cerebellum that plays a part in cognition and emotion.
Although further research is needed, it is clear that there’s more to the cerebellum than just movement.
What Happens When Your Cerebellum Is Damaged?
Because the cerebellum is primarily in charge of movement, most signs of a damaged cerebellum involve muscle control-related disturbances. They can include the following:
• Insufficient muscle control resulting in poor coordination
• Walking difficulties and limited mobility
• Difficulty speaking and/or slurred speech
• Reduced ability to judge the distance between objects
• Abnormal eye movements
• Frequent falling
The most common form of cerebellum dysfunction is known as ataxia.
Ataxia is the loss of muscle control and coordination, most often as a result of a cerebellum-related health problem like a virus or a brain tumor. Ataxia can also be genetic or occur as a result of stroke, head injuries, or cerebral palsy.
Your brain is susceptible to the effects of toxins, and the cerebellum is no exception. Ataxia can also be caused by prolonged exposure to solvents (e.g. paint thinners) or heavy metals like lead and mercury. What’s more, certain prescription drugs and alcohol are also known to cause ataxia.
Can You Live Without A Cerebellum?
In theory, living without a cerebellum should cause severe impairment of motor function, likely accompanied by cognitive and behavioral difficulties. In practice, however, this isn’t always the case.
A 2004 news story revealed that a then-24-year-old Chinese woman went to the doctor complaining about nausea, only to discover that she was one of just nine people in the whole world to have lived without their cerebellum.
This finally helped explain the problems that the woman had faced in early childhood. Namely, she was unable to walk until the age of 7 and her speech was mostly unintelligible until she turned 6. As an adult, however, she experienced no problems that would indicate a physical brain deficiency of any kind.
It turns out that the area of the brain where the cerebellum was supposed to be was instead filled with cerebrospinal fluid. This, in turn, provided cushioning for the brain and protected it against diseases. According to the doctors, this only proves how adaptable the human brain is.
How Can You Improve the Function of the Cerebellum?
There are many things that you can do to improve the function of your whole brain, including the cerebellum. Because this region of the brain is most involved in physical movement, you need to keep your muscles in optimal shape. The best way to do it is to exercise on a regular basis.
Your brain is like a muscle – it grows stronger with use.
– Jim Kwik, Author of Mindvalley’s Superbrain Program
The cerebellum also plays a role in cognition, which is why you need to take steps to increase brain power.
For example, you can take up meditation or yoga, listen to classical music, play chess, or master the art of the power nap. You can also try some proven techniques to improve your memory.
In addition, you should avoid all things that could cause physical damage to the cerebellum. This includes quitting smoking and limiting your alcohol consumption, wearing protective helmets while riding a bicycle, as well as boosting your immune system with wholesome foods to ward off viruses.
The Final Word
Housing more than 100 billion neurons, the cerebellum is a vital part of your brain. It coordinates muscle movement, helps you acquire and develop motor skills, and plays a vital role in vision.
Research also suggests that there is a link between the cerebellum and cognition, which is one of the reasons scientists are so eager to learn more about this region of the brain.
What are your favorite brain exercises that help improve the cerebellum function? Share with us in the comments below!