Precentral Gyrus
The structure indicated is the
precentral gyrus. A
gyrus is a ridge on the cerebral cortex, and is usually surrounded by grooves, known as
sulci.
Fissures are larger than sulci and divide the brain into lobes, as well as dividing the brain into right and left hemispheres.
The sulci anterior to the
precentral gyrus is known as the
precentral sulcus. This sulcus lies parallel to the
central sulcus (also referred to as the
fissure of Rolando/Rolandic fissure). The central sulcus separates the
parietal lobe from the
frontal lobe. The precentral gyrus contains the
primary somatomotor cortex. Learn more about the precentral gyrus in this anatomy tutorial on the
basic parts of the brain.