If a chronic pain patient's descending modulation pathway from the brainstem to the spinal cord malfunctions, which consequence follows regarding nociceptor signal transmission?

💡 Explanation

Malfunction of the descending modulation pathway, normally inhibitory, leads to reduced suppression of nociceptor signals; because this pathway often inhibits the release of Substance P, a key neurotransmitter in pain signaling, its malfunction amplifies Substance P release. Therefore, pain signals are heightened, rather than diminished by alternative inhibitory neurotransmitters.

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