If a patient has chronic pain, which outcome is likely if descending modulation via the periaqueductal gray (PAG) and rostral ventromedial medulla (RVM) is impaired?

💡 Explanation

If descending modulation is impaired, the ability of the brain to inhibit pain signals is reduced, because the PAG and RVM normally activate inhibitory interneurons in the spinal cord that suppress nociceptor activity. Therefore, pain perception increases, rather than being modulated effectively, unlike the other options.

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