Grey matter
The formation of the spinal nerve from the dorsal and ventral roots. (Grey matter labeled at center right.)
Latin	substantia grisea

Grey matter (or gray matter) is a major component of the central nervous system, consisting of nerve cell bodies (neurons), glial cells (astroglia and oligodendrocytes), capillaries, and short nerve cell extensions/processes (axons and dendrites).

Composition

It is composed of cell bodies as opposed to white matter (cell axons). It has a gray brown color which comes from the capillary blood vessels and the neuronal cell bodies.

Distribution

Grey matter is distributed at the surface of the cerebral hemispheres (cerebral cortex) and of the cerebellum (cerebellar cortex), as well as in the depth of the cerebral (thalamus; hypothalamus; subthalamus, basal ganglia - putamen, globus pallidus, nucleus accumbens; septal nuclei), cerebellar (deep cerebellar nuclei - dentate nucleus, globose nucleus, emboliform nucleus, fastigial nucleus), brainstem (substantia nigra, red nucleus, olivary nuclei, cranial nerve nuclei) and spinal grey matter (anterior horn, lateral horn, posterior horn).

Function

The function of gray matter is to route sensory or motor stimulus to interneurons of the CNS in order to create a response to the stimulus through chemical synapse activity. Gray matter structures (cortex, deep nuclei) process information originating in the sensory organs or in other gray matter regions. This information is conveyed via specialized nerve cell extensions (long axons), which form the bulk of the cerebral, cerebellar, and spinal white matter.

References

See also

• Gray matter heterotopia
• Neuropil
• Rexed laminae
• substantia nigra
• White matter

External links

• Gray+matter at eMedicine Dictionary