Central Nervous System Analgesia via Modulation (CNS Analgesia)

The central nervous system (CNS) modulates pain through complex networks involving the periaqueductal gray (PAG), rostral ventromedial medulla (RVM), and other brain regions. This modulation relies on opioid and non-opioid mechanisms, descending pathways, and targets such as opioid receptors (mu, delta, kappa) and endogenous ligands like endorphins. Activation of these pathways can inhibit nociceptive transmission at the spinal level, providing analgesia. However, the system is complex, with potential for both inhibition and facilitation of pain, and is implicated in placebo analgesia and various chronic pain conditions.

Other names

Descending Pain ModulationCentral Pain Modulation

Descending inhibition/disinhibition; bidirectional control of nociceptive transmission via opioidergic and non-opioidergic mechanisms in the PAG, RVM, and spinal cord. Activation of opioid receptors inhibits inhibitory interneurons, leading to enhanced suppression of ascending pain signals. Placebo analgesia also engages this circuitry.