 All of the sensory pathways in the body are made up by three consecutive neurons, which we call the first, second and third order neurons. There are three types of sensory information which travels the Dorsal Column Mediolemniscus pathway or DCML for short. That is vibration, fine touch and proprioception. For the rest of this video, we're just going to focus on the structure of the DCML. And to explore it in more detail, we're going to bring in these schematic models of the brain, brainstem and the spinal cord. So the impulse is generated at a sensory receptor. It then travels by the first order neuron's axon into the spinal cord. The cell body of the first order neuron is in the dorsal root ganglion just adjacent to the spinal cord. And then the axon moves up towards the brain in the white matter of the spinal cord, specifically in this area, which is known as the dorsal column. It's just a bunch of axons all moving in the same direction and carrying the same type of information. We divide the dorsal column further into two separate entities known as the grasal fasciculus and the cuneate fasciculus. Fasciculus sounds pretty daunting. It just means bundle in Latin. So it's another word that we use for bundle of axons. Now the muscle gracilis is in the leg. So that gives us a hint that the grasal fasciculus contains neurons that are coming from the lower limb. Our neuron here is coming from the upper limb, the shoulder, but it's going to be traveling in the cuneate fasciculus. I've removed this part of the spinal cord just to make things a bit clearer, but we're going to remove the medulla now to show where that first order neuron's axon ends up. It drops its info on the cell body of the second order neuron, which is inside the cuneate nucleus. From the cuneate fasciculus to the cuneate nucleus. And if it was coming from the lower limb, it would go from the grasal fasciculus to the grasal nucleus. The second order neuron's axon then swaps over to the other side of the body, which is a really important point to note in this pathway. It's called decassation, that process of crossing over. And the second order neuron's axon, just for this little part here, is called an internal arcuate fibre. It doesn't really add much value to that name, arcuate just means curved. And then onwards and upwards it continues inside the medial lemniscus. Lemniscus is yet another Latin name for bundle of axons. It literally means ribbon. So the medial lemniscus, a bundle of second order neuron axons, heads through the medulla and the pons and the midbrain as well, on its way towards the thalamus, which contains the cell bodies of the third order neurons. If we remove the thalamus, we can see that here. That cell body will be located in a particular nucleus of the thalamus, the ventral posterior nucleus. And the axon of the third order neuron initially heads through this area called the internal capsule, another bunch of white matter, and it heads up to terminate in the primary somatosensory cortex. So that's it for the dorsal column medial lemniscus pathway made up crucially by the dorsal column and the medial lemniscus. It's confusing to get your head around at first, but I guarantee that with time it will all become quite simple. Have a look at this model yourself if you'd like. There's a link in the video description below. Hit subscribe, hit the like button while you're at it and we will see you next time.