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Course: MCAT > Unit 4

Lesson 1: Foundations of behavior passages

Congenital analgesia


Congential insensitivity to pain, or congenital analgesia, is a condition in which individuals cannot appropriately sense painful stimuli. Some of these individuals cannot perceive painful stimuli at all (a condition called insensitivity to pain) while others can perceive pain, but cannot appropriately respond (a condition called indifference to pain). Patients can acknowledge and sense that they are coming into contact with a stimuli, but do not feel pain. Because of this congenital analgesia is an extremely dangerous condition; the inability to perceive or react to painful stimuli can lead to severe burns, lacerations, or other injuries, which can result in deadly infections or disease if wounds are left untreated.
In a study conducted on sensation and perception, researchers sought to determine the sensory thresholds of individuals with indifference to pain (IP group) as compared to individuals with normal sensitivity to pain (control group) . Each participant was exposed to changes in temperature, and asked to detect when the change occurred and how drastic the temperature change was. The mean results from each group are outlined in Table 1.
Table 1
Experimental conditionsIPControl
Response time to temperature change of 5 degrees300 ms30 ms
Response time to temperature change of 10 degrees280 ms20 ms
Response time to temperature change of 15 degrees250 ms15 ms
Response time to temperature change of 20 degrees200 ms10 ms
What would occur if the nerves connecting thermoceptors and mechanoreceptors to the brain converged into one nerve?
Choose 1 answer: