The inferior or orbital surface of the frontal lobe is concave, and rests on the orbital plate of the frontal bone. It is divided into four orbital gyri by a well-marked H-shaped orbital sulcus. These are named, from their position, the medial, anterior, lateral, and posterior orbital gyri. The medial orbital gyrus presents a well-marked antero-posterior sulcus, the olfactory sulcus, for the olfactory tract; the portion medial to this is named the straight gyrus, and is continuous with the superior frontal gyrus

Superior frontal gyrus

The superior frontal gyrus makes up about one-third of the frontal lobe of the human brain. It is bounded laterally by the superior frontal sulcus....

 on the medial surface.

Function

Bailey and Bremer reported that stimulation to the central end of the vagus nerve

Vagus nerve

The vagus nerve , also called pneumogastric nerve or cranial nerve X, is the tenth of twelve paired cranial nerves...

caused electrical activity in the inferior orbital surface. (http://brain.oxfordjournals.org/cgi/pdf_extract/75/2/244)

External links

• http://anatomy.med.umich.edu/atlas/n1a2p13.html