The term area 45 of Brodmann refers to a subdivision of the cytoarchitecturally defined frontal region of cerebral cortex. In the human, it occupies the triangular part of the inferior frontal gyrus and, surrounding the anterior horizontal limb of the lateral fissure, a portion of the orbital part of the inferior frontal gyrus. Bounded caudally by the anterior ascending limb of the lateral fissure, it borders on the insula in the depth of the lateral fissure. Cytoarchitectonically it is bounded caudally by the opercular area 44 of Brodmann, rostrodorsally by the area 46 of Brodmann and ventrally by the area 47 of Brodmann ( Brodmann-1909 ).