periaqueductal gray
Pain modulation center
The periaqueductal gray is a region of gray matter in the midbrain surrounding the cerebral aqueduct.
It plays a central role in pain modulation—the body's ability to suppress pain signals—and is involved in defensive behaviors, vocalization, and autonomic functions.
Opioids and endorphins act partly through this structure: Stimulation of the periaqueductal gray can produce profound analgesia.
- analgesiaAbsence of sensation
- midbrainMiddle brain division
- vocalizationProducing sounds with voice
- fight-or-flightAcute threat reaction
- suffocationFatal lack of air
defensive behavior · inferior colliculus · freezing · endorphins · superior colliculus · brainstem · panic · hypothalamus · lordosis · gray matter · rage · opioid · locus coeruleus · pain · autonomic · survival · crying · limbic
- brain regionscerebrum, frontal lobe, temporal lobe, parietal lobe, occipital lobe
- brainstembrainstem, brain stem, medulla, medulla oblongata, pons
- painache, pain, agony, hurt, hurting
- limbic systemhippocampus, amygdala, hypothalamus, fornix, mammillary bodies
- opioidsmorphine, codeine, heroin, fentanyl, oxycodone
aquarium, aquatic, peripheral, induction, aqueduct, ductile, periscope, aquifer, ducted