Identify and shade in the locations of all the ascending sensory ...

Question

Identify and shade in the locations of all the ascending sensory tracts in the following diagram of the spinal cord.

Accepted Answer

Welcome back. Everyone. Here's our next problem, determine the right labeling of A through D on the spinal cord diagram below. And we have a diagram here showing some portions in the white matter of the spinal cord starting with a large portion labeled A uh in the most posterior arrangement. In this diagram, the posterior portion of the spinal cord is on the top and the anterior region is down below. So the A is a very large region up on in towards the posterior, just underneath the posterior root which is labeled on our diagram. Then right underneath A, we have on the outside a small region labeled B and then just immediately interior to that a small region labeled C and then in the most anterior portion, a small region labeled D. So when we look at our answer choices, we have four different tracks labeled and it's the same ones in each choice just labeled differently. So I'm just going to read off answer choice. A know that all of the different possibilities of labels are the same, just assigned to different letters. So we have our letters A through D answer choice A says capital a anterior spinocerebellar tract, capital b, posterior spinocerebellar tract, capital c anterior spinothalamic tract or capital d lateral spinothalamic tract. So, those are our choices for what these regions are. Let's think through which is which. So let's recall that these tracks are within the white matter of the spinal cord. So they're axons with their white myelin sheaths and these tracks are groups of axons with a common origin and common destination. I'm looking at the names of these tracks that are given, we're talking about somatic sensory pathways or we're talking about ascending pathways. So let's think about what we're looking at here. Well, we know which are the anterior and posterior regions. So when we look at A, we know this is the most posterior of the labeled areas. So we would expect choice A to be a posterior tract. So let's look at our answer. Choices and choice B has a being the posterior spinal cerebellar tract and choice C has a being the posterior spinocerebellar tract. So we'll go ahead and rule out choice A which has a being anterior and choice D which also has a being anterior when we have the name spinocerebellar tract, that would mean that this originates in the spine and goes to the cerebellum. Well, now we've moved down to Choice B or not Choice B but region B, region B is anterior to region A, but it's on the outside just as region A is. So that's going to be anterior and it's going to be the same kind of tract, anterior spino cerebellar. So let's look at our answer choices and see which has that option. Answer choice B has region B as anterior spinal cerebellar as does regency or excuse me, regions and answer choices are getting a little confusing here. Answer choice C as region B as anterior spina cerebellar. So both the same will move on. So now we have our next region, region C, it's labeled in green sort of interior to region B. Now we're moving on to these spinothalamic tracts. So these originate in the spine and take sensory in information to the thalamus. And we've got region C being posterior to region D. So we'd expect region C to be the posterior spinal thalamic tract. Well, we don't have a choice of posterior, but we do have a choice of lateral. And you can see that region C is lateral to region B. So that is indeed the correct name. And we see that answer choice C has regency as the lateral spinothalamic tract. Whereas choice B has regency as the anterior spinothalamic tract. Finally, we move on to region D. We've only got one answer choice left. So we can pick choice C as our answer choice. But let's just confirm that it's correct region D is in the anterior part of the spinal cord. So we would expect region D to be the anterior spinal thalamic tract which indeed, it is when we look at to C. So that confirms that our answer here in terms of correctly labeling regions A through D is choice C region A is the posterior spinocerebellar tract region B, the anterior spinocerebellar tract region C, the lateral spinothalamic tract and region D the anterior spinothalamic tract. See you in the next video.

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Identify and shade in the locations of all the ascending sensory tracts in the following diagram of the spinal cord.

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