Final answer:
Protopathic sensation relates to the ability to perceive general sensations like pain and temperature, transmitted by the spinothalamic pathways. Epipathic sensation is associated with refined sensory information such as fine touch and proprioception, carried by the dorsal column pathways. Sensory discrimination is hence a function of these separate ascending tracts in the spinal cord.
Step-by-step explanation:
The difference between protopathic and epipathic sensations relates to the types of sensory information they convey. Protopathic sensation involves the ability to perceive general sensations such as pain, temperature, and coarse touch, which are transmitted via the spinothalamic pathways. For example, the sensation of burning your finger on a hot stove is a protopathic sensation. On the other hand, epipathic sensation involves the transmission of more refined sensory information like fine touch, vibration, and proprioception through the dorsal column pathways. Identifying a key in your pocket without seeing it is an example of an epipathic sensation.
These differences illustrate the separation of sensory information in the ascending tracts of the spinal cord. The spinothalamic pathway carries protopathic sensory information, while the dorsal column carries epipathic sensory information. Discrimination between light touch and painful stimuli is therefore tied to the functioning of these two distinct ascending tracts.
There are various sensory pathways that carry peripheral sensations to the brain, known as ascending pathways or tracts. These pathways are responsible for the transmission of tactile and somatosensory stimuli from receptors in the skin, muscles, tendons, and joints.