While
cleaning up the stove after cooking a meal, you inadvertently
touch a burner that is still hot. You immediately withdraw your
hand from the hot burner, but you receive a mild burn on your
little finger. You sense a sharp pain at first, which becomes
a dull ache after an hour. Activation of which pathway lead
to these sensations?
You
Answered:
 | Spinothalamic
tract |
Correct
Pain
is a subjective sensation that serves a protective role for the
individual. For example, in the scenario above, you withdrew your
hand from the stove to prevent being burned. Pain is subjective
because people have different thresholds for pain, and even different
cultures respond to potentially painful stimuli in different ways.
On the other
hand, the sensory nerve fibers that ultimately result in pain
operate similarly in all of us; that is, their thresholds for
activation are similar in everyone. Hence the cerebral cortex
determines whether a potentially painful stimulus (that is, a
stimulus that excites nerve endings sensitive to tissue injury)
will be interpreted as "pain."
Furthermore,
the cortex ultimately determines the intensity of pain. Because
of the individual variability in the interpretation of pain, coupled
with the similarity in the responses of sensory neurons, we refer
to neurons that are sensitive to stimuli that can evoke the sensation
of pain as "nociceptive" neurons or simply "nociceptors".
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