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Cerebellum

Created by Matthew Barry Jensen.

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  • blobby green style avatar for user Lyna L'Heureux
    So the cerebellum hemispheres coordinate movements on the same on the body contrary to the cerebrum hemispheres ?
    (30 votes)
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    • starky seedling style avatar for user Elena
      I think you're misreading the diagram, as you look at the screen, he shades the "left" cerebellar hemisphere orange on the back view diagram, and the "left" side of the body on a front view diagram, which is our right arm, right leg etc.
      (2 votes)
  • blobby green style avatar for user K Taylor
    Is the cerbellum responsible for so called "muscle memory", like how you can ride a bike with ease even if you haven't done so for some time?
    (9 votes)
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    • blobby green style avatar for user Leanne Bishop
      Yes Yes. The cerebellum regulates and stores learned movements such as stair climbing, walking and bike riding. It is also controls the force rate and direction of movement in both the feed forward system as well as the feedback system, coordinating incoming sensory information to adjust movement
      (12 votes)
  • blobby green style avatar for user Stacy McGill
    Hello, my son was born normal C-section, seven months old diagnosed with infantile spasms, treated with AC TH, he's been nonverbal most of his life he's 19 now. What is the relationship between the cerebellum and nonverbal ?
    (4 votes)
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  • aqualine sapling style avatar for user mcgratoh
    Does alcohol affect the cerebellum? I heard that's what causes you to become all uncoordinated when drunk, but why the cerebellum (if it at all)?
    (1 vote)
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  • leafers tree style avatar for user Ryan
    To clarify, since he labeled the sides of the cerebellum from the back, the L and R sides are in the person's perspective, correct? So my L side is controlled by my R hemisphere? (from my perspective)
    (2 votes)
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    • female robot ada style avatar for user Lidiya
      No, your left side of the body is controlled by your left cerebellum hemisphere, or better to say "fine-tuned", because the "fine-tuned" interpretation of the muscle movement is sent from the left cerebellum hemisphere to the right cerebral cortex. When the corrections are accepted, it is the right cerebral cortex, which will be sending this message to the left side. Cerebellum works ipsilaterally, cerebrum works contralaterally. I hope this makes sense.
      12/29/15: I see that someone "thumb-ed down" my answer as wrong. Therefore, I have to attach the link to the Mayo Clinic webpage that says that "The right side of your cerebellum controls coordination on the right side of your body; the left side of your cerebellum controls coordination on the left" ( http://www.mayoclinic.org/diseases-conditions/ataxia/basics/causes/con-20030428). I hope Mayo Clinic gets more respect from the someone who does not understand the difference between cerebellum and cerebrum.
      (2 votes)
  • duskpin sapling style avatar for user Amanda Nylen
    Is there any more videos about the cerebellum that goes into more detail of its fuction?
    (2 votes)
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  • blobby green style avatar for user 😊
    is the cerebellum associated as an upper motor neuron
    (1 vote)
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  • blobby green style avatar for user moathmoo
    Hi
    Thank you so much for this great video.. but you mentioned that its only an introduction so my question where can i fined the detailed video ?
    Again thank you
    (1 vote)
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  • leafers seed style avatar for user sierra gonzales
    If someone were to have an injury, specifically a concussion to the cerebellum, what would be the effect on the nervous system?
    (1 vote)
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  • piceratops tree style avatar for user Daniela Rojas
    A 65-year-old woman experiences clumsiness of movement of her right arm and leg. She cannot perform rapid alternating movements, walks with an ataxic gait and, when reaching for an object with her right hand, misjudges and overshoots the position of the object, showing a marked movement tremor. Her motor power and the sensation in her right limbs appear to be intact. This woman likely has damage to the:
    (1 vote)
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    • duskpin ultimate style avatar for user Betty :)
      I would agree with Daniela. It should be the right cerebellum, here's my reasoning:

      1. Clumsy movement of right arm and leg
      This implies that it's either contralateral in the left cerebrum or ipsilateral in the cerebellum. The association with motor control however, leans my estimation to the cerebellum, which has a stronger connection to motor function.

      2. Walks with an ataxic gait
      Ataxia is a common cerebellar disorder as it results in impaired motor function

      3. When reaching for an object with her right hand, misjudges and overshoots
      The cerebellum is responsible for coordinating the timing and force of different muscle groups to produce fluid limb or body movements. If it's impaired, it may produce movements that over or underestimate the intended goal.

      I hope these help!
      (1 vote)

Video transcript

Voiceover: In this video, I'm going to talk about the cerebellum, "Cerebellum." Which sounds a lot like the cerebrum but it's a different part of the brain. So if you look at the brain over here from the front, we have the cerebrum on top, with the right and the left cerebral hemispheres. And we have the brain stem underneath that connecting to the spinal cord and then behind the brain stem and below the cerebrum is the cerebellum. Let me just color that in here and you can't see it that well from the front because it's behind the brain stem. But if we come over here to the back, we're looking at the back of the brain, The cerebrum is on top, here would be the left cerebral hemisphere and here would be the right cerebral hemisphere. And here you can see more of the cerebellum because it's behind the brain stem. So now we can't see much of the brain stem because the cerebellum is covering it up. And the cerebellum is also divided into hemispheres here would be the left cerebellar hemisphere and here is the right cerebellar hemisphere. And now we just see the brain stem coming into the spinal cord down here, but we've cut off the spinal cord. Now the cerebellum does a number of different functions but probably the most obvious thing that it does is it coordinates movement. "Coordinates movement." And it's pretty neat how it does this, how it works with the other motor structures in the nervous system to coordinate movements. Because the cerebellum really smooths out movements and it makes them more accurate. Like if you're trying to touch something with your finger, the cerebellum plays a big role in your accuracy and your finger touching the object that you're shooting for. And there's kind of three parts to how information travels into and out of the cerebellum to let it do its job of coordinating movements. Let me write three little marks here, and we'll quickly go over the three parts. And the first thing the cerebellum needs to do is it needs to get information about the motor plan. "Motor Plan." And the motor plan involves which muscles need to contract and at what intensity and what duration, how strongly to contract those muscles and for how long they contract those muscles to do some kind of movement that you want to do. And don't worry about the anatomy of this stuff for this introductory discussion of the cerebellum. But in other videos we can go into more detail on how the motor plan is developed up in areas of the cerebral hemisphere that plan movements and then to make those movements happen. Upper motor neurons up here in the cerebrum send their axons down through the cerebrum and the brain stem and they cross over. And don't worry about the anatomy of this, but then they talk to lower motor neurons for example some lower motor neurons in the upper part of the spinal cord here that'll send information out, let's say to a muscle, muscles in the arm that'll tell the arm to move in a certain direction. And do some kind of movement with the arm that you want to do and that actually makes the movement happen. But while all that is going on while the movement is actually being executed by the upper motor neurons and the lower motor neurons and the muscles that they're synapsing on, information about that motor plan is also being sent to the cerebellum. So there's another pathway that sends information down through the cerebrum and into the brain stem and then that information passes over and into the cerebellum so that the cerebellum is aware of the motor plan. So now that the cerebellum is aware of what the motor plan is now it wants to know how the movement is actually going, so that it receives position sense information. "Position Sense Information." And this is position sense information that isn't reaching consciousness, we're not aware of it. It's just going to the cerebellum so that their receptors involved in position sense, like the muscle spindles that sense, stretch of skeletal muscles out here in the body. And then some [ada] sensory neurons bring that information back into say the spinal cord, if we're talking about a movement of the arm. And then once that information enters the spinal cord There are tracks that will carry that information up into the brain stem and then into the cerebellum. So then now the cerebellum knows what the motor plan was and then it can compare that to the movement that's actually occurring by looking at this position sense information and it can see if the movements occurring according to plan or if corrections are necessary. If the movements need to be fixed somehow to make it smoother and more accurate and usually that is the case, there does need to be some kind of correction to get the movement to match the motor plan. So then the cerebellum needs to send feedback back to the motor areas. "Feedback." Back to the motor areas of the cerebrum the areas that came up with the motor plan in the first place to try to correct that movement while it's occurring. So that feedback information will travel from the cerebellum through the brain stem and then to parts of the cerebrum and then back to the motor areas of the cerebral cortex. And then they can use that feedback information from the cerebellum to fix the movement to make it smoother and more accurate by changing the activity of the upper motor neurons. It'll change the activity of the lower motor neurons. It'll change the activity of the skeletal muscles that are performing the movement. So again don't worry about the actual anatomy and the pathways now, it's introductory level but this is kind of the bird's eye-view of the way information flows in and out of the cerebellum to help coordinate movements. And without getting too deep into the anatomy of the cerebellum, one little detail about the way the cerebellum is set up in general is that the kind of middle part of the cerebellum here toward the midline tends to mostly coordinate kind of movements involving the middle of the body I like to think of, in a particular walking. So the muscles of the trunk and the legs involved in walking get a lot of coordination from the middle of the cerebellum here. While the part of the cerebellum more on the side here, farther over to the side of the cerebellar hemisphere is more involved in coordinating movements of the limbs. So coordinating movements of your arms and the legs when they're being used individually that involves a lot of activity of the cerebellum over on the side here. And then a bunch of different parts of the cerebellum coordinate movements involved in speech, let me just draw a little mouth here saying, "Hi." Because we actually have lots of little muscles that have to move in our lips and tongue and throat to speak properly and to enunciate. And if the cerebellum isn't functioning properly we can have trouble coordinating those, and trouble enunciating. And the cerebellum, parts of the cerebellum are also very involved in moving our eyes around. These are not very good drawings of eyes but the movements of the eyes to look where we want to look depend on functions of the cerebellum that kind of coordinate those muscles that move the eyes. So there's a lot more details to the cerebellum but I'll stop here cause I just want to introduce where the cerebellum is and kind of its major function in coordinating movements and the different types of information it uses to accomplish that function.