Anatomy
A gyrus located anterior to the central sulcus. It extends anteroinferiorly from the great longitudinal fissure and ends just above the lateral sulcus. It forms part of the frontal lobe.
Blood supply:
Supplied by the middle cerebral artery, and medially by the anterior cerebral artery, to a lesser extent.
Functions
Is the location of the primary motor cortex, which is involved in voluntary controlled movement of the opposite side of the body. The body is represented on the precentral gyrus as a somatotopic motor map. The foot and lower limb occupy the medial aspect of the gyrus while hand, upper limb, torso, neck and head occupy the lateral aspect. The area of precentral gyrus devoted to a particular body region is proportional to the degree of motor control of which that region is capable e.g. the hand area is considerably larger than the foot.
Clinical
Lesions of the precentral gyrus can cause contralateral hemiparesis.
Interested in taking our award-winning Pocket Anatomy app for a test drive?
