Editing Trigeminal nerve (section)

===Summary===
The complex processing of pain-temperature information in the thalamus and cerebral cortex (as opposed to the relatively simple, straightforward processing of touch-position information) reflects a [[Phylogenetics|phylogenetically]] older, more primitive sensory system. The detailed information received from peripheral touch-position receptors is superimposed on a background of awareness, memory and emotions partially set by peripheral pain-temperature receptors.

Although thresholds for touch-position perception are relatively easy to measure, those for pain-temperature perception are difficult to define and measure. "Touch" is an objective sensation, but "pain" is an individualized sensation which varies among different people and is conditioned by memory and emotion. Anatomical differences between the pathways for touch-position perception and pain-temperature sensation help explain why pain, especially chronic pain, is difficult to manage.