Fine Touch and Crude Touch
Fine touch, (or discriminative touch), is a sensory modality which allows a subject to sense and localise touch. The form of touch where localisation is not possible is known as crude touch. The posterior column-medial lemniscus pathway is the pathway responsible for the sending of fine touch information to the cerebral cortex of the brain.
Crude touch (or non-discriminative touch) is a sensory modality which allows the subject to sense that something has touched them, without being able to localize where they were touched (contrasting "fine touch"). Its fibres are carried in the spinothalamic tract. Unlike the fine touch which is carried in the dorsal column
As fine touch normally works in parallel to crude touch, a person will be able to localize touch until fibres carrying fine touch (Posterior column-medial lemniscus pathway) have been disrupted. Then the subject will feel the touch, but be unable to identify where they were touched.
Read more about this topic: Somatosensory System
Famous quotes containing the words fine, touch and/or crude:
“In a universe that is all gradations of matter, from gross to fine to finer, so that we end up with everything we are composed of in a lattice, a grid, a mesh, a mist, where particles or movements so small we cannot observe them are held in a strict and accurate web, that is nevertheless nonexistent to the eyes we use for ordinary living—in this system of fine and finer, where then is the substance of a thought?”
—Doris Lessing (b. 1919)
“Go, Soul, the body’s guest,
Upon a thankless arrant:
Fear not to touch the best;
The truth shall be thy warrant:
Go, since I needs must die,
And give the world the lie.”
—Sir Walter Raleigh (1552?–1618)
“Of course you will pooh-pooh whatever’s fresh and new, and declare
it’s crude and mean;”
—Sir William Schwenck Gilbert (1836–1911)