Answer to Question #101536 in Genetics for Nina

Question

Describe the anatomical bases of the touch and pain pathways from the periphery to the somatosensory cortex

Answer 1

Anatomical basis of pain-

Pain begins in free nerve endings in the skin. It is then propagated to the dorsal horn of the spinal cord where they synapse on dorsal horn neurons. These dorsal horn neurons then decussate (cross the midline) to the lateral spino-thalamic ascending white mater and ascend through the medulla to the thalamus where they synapse on thalamic neurons. From here pain is relayed to both sensory cortex and cingulate cortex respectively.

Anatomical basis of touch-

Touch begins in the basically all other sensory cells in the skinnd then travels via A beta fibres. These fibers then ascend via dorsal column medial lemniiscal pathway WITH OUT decussating. They first ascend in the dorsal collumn and synapse in the medulla at the their respective nucleus . From there the fibers decussate in the internal arcuate fibers and join to form the medial lemniscus. These fibers then synapse once more in the VPN of the thalamus be for hitting the primary somatosensory cortex.