[MUSIC] Cerebellar function is topographic. It's topographically arranged. So there's a central portion of the cerebellum. This is a, schematic of a cerebellum and the central portion called the Vermis is going to control midline, movements. Movements such as postural control, gait, and speech. This area next to the vermis is called the Paravermis and that is controlling our, our movements of our arms. So we have midline and then, and limbs. And then we have all this extra stuff. This extra stuff the lateral lobes that is if we look here we're, we're this a cut through the mid saggital so it's a cut through the vermus. And the lateral lobes out here are really large. In a rodent for instance, there's almost no lateral lobes. It's a very large Vermis, there's a little bit of a Paravermis and then there's almost nothing. Because rodents pretty much use their trunk and a their proximal limb muscles, but they're not, they're not playing the piano. And but associated with this, large lateral lobes is this large pons. The base of the pons here, this is married to the lateral lobes of the cerebellum. So these two structures evolved together. And it's only in us and in primates that we have this bulbous pons. And it's only in primates and a few other animals, animals like dolphins where this is greatly expanded. Okay. So, what difference does that make? Well, if we have a problem, a tumor and, in fact, cerebellar tumors are unfortunately relatively common amongst children. So cerebellar tumors in the vermis are going to, are going to effect walking, standing, and speech. Cerebellar tumor in the paravermis, which are less common, are going to affect reaching. But, strokes, and cardiovascular episodes that in older people that affect para vermes are going to affect reaching movements. Now when the lateral lobes are affected, sometimes nothing happens or nothing dramatic is apparent. And that has led people to, to really be little bit confused as to what lateral lobes are, are doing, and I think that confusion persist to this day, I think it's an open question. It's possible, number one, that they're involved in motor learning and so that existing things that we know how to do are fine when the lateral lobes are damaged but maybe we can't learn some new fancy skill, motor skill. Another possibility is that these lateral lobes are important in some non motor functions such as, language communication. Such as assessing the emotional temperature of a group. And so there are, there are ways in which the processing that the cerebellum does for motor output could also be applied to non-motor output. You can imagine that perhaps, in a very, automatic way, you enter into a social group. And you look around and automatically you can see. Whether there's tension in the room, whether there's not tension in the room. And you're, how are you doing that? You're doing it pretty much unconsciously. You're taking in a lot of sensory information, you're making some kind of transform and the outcome is some kind of judgement. Maybe that's the kind of thing that happens in the lateral lobes. But that's far from from a clear consensus in the field. And finally, the, the, final part of the cerebellum is the flocculus. The flocculus and, and, a piece of the vermis are involved eye movement, coordination. Absolutely critical to making sure that our eyes move and our, we keep our gaze steady even as we move about in the world. So for the vestibular ocular reflex that you're going to look at in, in a couple segments also for, for smooth pursuit, which means. If I see a bird going across the sky I can actually latch my gaze onto that bird and then follow that bird going across the sky, I can smoothly follow that bird bird's path across the sky and I need my cerebellum to do that. So there's a basic typography the pont of this segment is just to understand that there's a typography, the vermis is midline structures and midline functions. Paravermis are, things that we do with our hands and our legs. And, the lateral lobes and the Flocculus have other functions. [MUSIC]
