Lateral Sulcus

The lateral sulcus, also called Sylvian fissure, is the deepest cortical fissure of the brain. It stretches between the frontal and temporal lobes, then goes back and upward over the lateral aspect of the cerebral hemisphere. The lateral sulcus divides the frontal lobe and parietal lobe above from the temporal lobe below. The lateral sulcus is situated in both cerebral hemispheres but it is longer in the left hemisphere.

The Sylvian fissure has a number of side branches. Two of the most prominent and most regularly found are the ascending ramus and the horizontal ramus of the lateral fissure, which subdivide the inferior frontal gyrus. The lateral sulcus also contains the transverse temporal gyri, which are part of the primary auditory cortex.