part_of part of part of Homo sapiens anatomical structure brain central nervous system oculomotor nuclear complex midbrain ventral tegmental area central gray substance of midbrain http://upload.wikimedia.org/wikipedia/commons/d/da/Cn3nucleus.png EV:0100249 anulus aqueductus cerebri central (periaqueductal) gray midbrain periaqueductal grey periaqueductal grey neuronames:510 griseum centrale mesencephali periaqueductal gray HBA:9003 periaqueductal gray matter CGMB periaqueductal gray, proper pAG central grey substance of midbrain GAID:585 BIRNLEX:973 periaqueductal grey substance MESH:D010487 UMLS:C0228398 SCTID:369233003 EMAPA:32781 substantia grisea centralis mesencephali Wikipedia:Periaqueductal_gray BM:MB-PAG BAMS:CGMB anulus aquaeductus central gray substance of the midbrain UBERON:0003040 central gray of the midbrain periaqueductal grey matter BAMS:PAG griseum periventriculare mesencephali MA:0000209 periaquectuctal grey BTO:0002701 Periaqueductal gray (PAG; also called the 'central gray') is the gray matter located around the cerebral aqueduct within the midbrain. It plays a role in the descending modulation of pain and in defensive behaviour. The ascending pain and temperature fibers of the spinothalamic tract also send information to the PAG via the spinomesencephalic tract. The spinomesencephalic tract is so-named because the fibers originate in the spine and terminate in the mesencephalon, another name for the midbrain, the part of the brain in which the PAG resides. [WP,unvetted]. periaqueductal gray of tegmentum FMA:74510 TAO:0000518 s. grisea centralis anulus of cerebral aqueduct MA:0002895 MBA:795 substantia grisea centralis DHBA:12209 central gray EFO:0002470 griseum centrale central grey