If descending modulatory pathways from the periaqueductal gray (PAG) are lesioned, which consequence follows regarding nociceptor signaling after a painful stimulus?

💡 Explanation

Lesioning the PAG disrupts descending pain inhibition; because this pathway normally inhibits nociceptor activity through the release of endorphins and enkephalins, the lesion will remove this inhibition. Therefore, nociceptors will fire more action potentials in response to a painful stimulus, rather than experiencing decreased substance P release or increased inhibitory signaling.

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