Asked by: Lorenzo Metais
medical health brain and nervous system disorders

What is periaqueductal gray matter?

Last Updated: 25th January, 2020

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The periaqueductal gray is the gray matter located around the cerebral aqueduct within the tegmentum of the midbrain. It projects to the nucleus raphe magnus, and also contains descending autonomic tracts. This region has been used as the target for brain-stimulating implants in patients with chronic pain.

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Also to know is, what is the function of periaqueductal gray of the brainstem?

The periaqueductal gray (PAG) is an anatomic and functional interface between the forebrain and the lower brainstem and has a major role in integrated behavioral responses to internal (e.g., pain) or external (e.g., threat) stressors.

One may also ask, what is the PAG in the brain? The periaqueductal gray, or PAG, is an area of gray matter found in the midbrain. The PAG surrounds the cerebral aqueduct (hence the name periaqueductal) and occupies a column of brainstem that stretches about 14 mm long.

Likewise, people ask, what does periaqueductal mean?

Medical Definition of periaqueductal : of, relating to, or being the gray matter which surrounds the aqueduct of Sylvius.

What is the descending pain pathway?

The circuit that consists of the periaqueductal gray (PAG) matter in the upper brain stem, the locus coeruleus (LC), the nucleus raphe magnus (NRM) and the nucleus reticularis gigantocellularis (Rgc) contributes to the descending pain suppression pathway, which inhibits incoming pain information at the spinal cord

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Anatomical terms of neuroanatomy
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What are the four phases of of the pain pathway?

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