 In this video we'll explore one path that sensory information takes to the brain. This pathway conveys sensations of crude touch, firm pressure, pain and temperature. It transmits information from a sensory receptor in the body and as is in the shoulder here up to the primary somatosensory cortex which is found in the post-central gyrus of the parietal lobe of the brain. When we talk about this binothalamic tract pathway we are referring to three consecutive neurons. These are known as first, second and third order neurons. First receives the sensory information so let's imagine that's the feeling of pressure when you lean against a wall and then it passes this information to the second order neuron. Second passes to third and third passes to the brain. To explore this in a bit more detail we'll bring in some more schematic models the brain, brainstem and spinal cord. Now our first order neuron has its cell body in a bunch of gray matter just adjacent to the spinal cord. It's the dorsal root ganglion and its axon runs from the sensory receptor and then joins in with the white matter of the spinal cord. First of all it ascends just one or two vertebral levels in the posterior lateral tract which is also known as Lysauer's tract. A tract is really just a bundle of axons. Okay so the first order neuron drops its information on the cell body of the second order neuron which is located in the dorsal horn of the spinal cords gray matter. The axon of the second order neuron immediately crosses over to the other side of the body and this process this crossing over is known as decussation. So for the spinothalamic tract pathway decussation occurs in the spinal cord. The axon then becomes part of a bundle of axons traveling in the same direction and this is the spinothalamic tract. There are actually two parts of the spinothalamic tract there is the anterior part and the lateral part. Neurons carrying information about crude touch and firm pressure travel in the anterior spinothalamic tract like ours. If they carry information about pain and temperature they travel in the lateral spinothalamic tract. So from the wall we're leaning on we're receiving this information about firm pressure so a neuron will be traveling up the anterior spinothalamic tract and it continues through the medulla pons and the midbrain and then they pass their information to the cell body of the third order neuron which lies in the thalamus. There it is there and the axon to the third order neurons move through an area which is known as the internal capsule bundle of white matter again. The axons then terminate in the primary somatosensory cortex. Click the link below to revise your understanding of this pathway with this model. Hit subscribe and hit the like button while you're at it. Have fun learning this stuff and I was confusing it first but you'll get your head around it eventually. Thanks for watching and we will see you next time.