Posterior column-medial lemniscus pathway (PCML)
Upon completing this study unit, you will be able to:
- Identify the components of the posterior column-medial lemniscus (PCML).
- Describe the pathway of the PCML pathway.
- Discuss the types of sensory information carried by the PCML pathway.
The posterior column-medial lemniscus pathway (PCML) is a sensory pathway of the central nervous system that conveys information about fine touch, two-point discrimination, proprioception, and vibration sensations from the skin and joints. Its name is derived from the two major structures that comprise the PCML:
- Posterior column, which transmits information through the posterior (dorsal) column of the spinal cord and terminates in the medulla oblongata. It is formed by two large bundles of nerve fibers: fasciculus gracilis and fasciculus cuneatus.
- Medial lemniscus, which continues the posterior column in the brainstem and carries information to the thalamus, which then relays it through the internal capsule to the somatosensory cortex.
Learn more about the posterior column-medial lemniscus pathway (PCML) by watching the video below!
Take a quiz
Now that you have watched the video, test and consolidate what you’ve learned with our quiz tailored for the posterior column-medial lemniscus pathway!
Did you know that you can actually create your own quiz on Kenhub? Take a look at the following quiz which covers the pathways of the nervous system.
Take a closer look at the posterior column medial lemniscus pathway in the gallery below.
Posterior column: Spinal cord
Medial lemniscus: Brainstem
|Pathway||Peripheral sensory receptors → Ganglion spinale → Fasciculus gracilis / cuneatus → Nucleus gracilis / cuneatus → internal arcuate fibers (decussation) → medial lemniscus → ventral posterolateral nucleus of thalamus → primary somatosensory cortex|
|Function||Sensory pathway that conveys information about fine touch, vibration, proprioception and pressure sensations from the skin and joints|