Insular Lobe

The oval region of cortex located in the depths of the lateral fissure is the insular lobe. This area is characterized by a set of long gyri in its caudal part (the gyri longi) and a set of short gyri in its rostral part (the gyri breves). These gyri are separated from each other by the central sulcus of the insula. The insular cortex is continuous, at the circular sulcus of the insula, with that of the adjacent frontal, parietal, and temporal lobes. This continuity forms lips on each lobe that overlie the insula to form the frontal, parietal, and temporal opercula. The limen insulae (threshold to the insula) is the area in which the inferior surface of the hemisphere is continuous with the insular cortex. Although the function of the insula is still somewhat unclear, it is known that the insular cortex receives nociceptive and viscerosensory input. However, it is known that spontaneous lesions of the insular cortex may result in the diminution or complete loss of the desire to continue addictive behavior, such as smoking.