That Neuroscience Guy - Neuroscience Bites-The Premotor Cortex

Episode Date: December 15, 2022

Next in our series of Neuroscience Bites, we discuss the Premotor Cortex: a brain area important for movement planning. 

Hi, my name is Olof Kregolsen and I'm a neuroscientist at the University of Victoria. And in my spare time, I'm that neuroscience guy. Welcome to another neuroscience bite. On the last bite, we talked about the supplementary motor area. So it only makes sense that on this bite, we talk about the premotor cortex. Now, if you go to my blog on olafkregolson.com or thatneuroscienceguy.com, you'll see a good image where it shows that the supplementary motor area is closer to the midline and the premotor cortex is more lateral on both sides of the brain. In fact, another name for the premotor cortex is more lateral on both sides of the brain. In fact, another name for the premotor cortex is the lateral premotor area. So those two names refer to the same thing. Interestingly, the premotor parts of the brain are about six times the size of the primary motor cortex, which shows

you just how much emphasis there is on movement planning and how complex it is. Now, how do these regions differ? Well, as I said with the supplementary motor area, both of these regions are not fully understood, but we know that they play a role in movement planning. People with deficits to these regions have trouble planning movements. With that said though, while the supplementary motor area seems to play a greater role in internally generated movements, the premotor cortex seems to play a greater role in externally generated movements. What I mean by that is, imagine driving. Driving is largely mediated by the road that's in front of you, and that's an externally generated movement. Hitting a baseball, to a large extent,

is an externally generated movement. Now, there is an internal component, which is why these two regions of the brain work together quite frequently. The premotor cortex also seems to play a pretty big role in encoding movement directions there's a lot of really cool studies that show that the premotor cortex is sensitive to the direction that you want to move in or neurons within the premotor cortex are sensitive to all the different directions that you want to move in and finally the premotor cortex seems to play a role in controlling the trunk of the body. So if you remember, the supplementary motor area was more aligned with the extremities of the body. The premotor cortex seems to play a greater role in the muscles of the body that are closer to the midline or the trunk muscles, if you will.

Anyway, that's another bite and just an update on another part of the brain, the premotor cortex. So together with the supplementary motor area, the two major movement planning regions of the brain. Just a reminder, check out the website. I'm not going to do the full bump. You can go there. You can find links to everything, our Twitter feed, the blog that supports this, our Etsy store, Patreon. Please check it out. And thanks, of course, for subscribing. We really, really appreciate it.

My name is Olive Krigolson, and this has been another Neuroscience Byte. Thank you so much for listening.