area 45 (45)
The term area 45 refers to a subdivision of the frontal lobe defined by internal structure. It is located in the triangular part of the inferior frontal gyrus. Identified on the basis of multiple stains, it is separated more or less topologically as follows: caudally, from the opercular part of the inferior frontal gyrus by the anterior ascending limb of the lateral fissure; rostrally, from the orbital part of the inferior frontal gyrus by the anterior horizontal limb of the lateral fissure; dorsally from the middle frontal gyrus by the inferior frontal sulcus; and ventrally from the insula by the superior limiting sulcus.
Architectonically, it and area 44 constitute the ventrolateral prefrontal cortex. It is bounded caudally by area 44, rostroventrally by area 47, and rostrodorsally by area 9/46. It has two components: an anterior area 45A and posterior area 45B.( Petrides-2012 ).
Equivalent to area 45 of Brodmann, it and area 44 are considered to represent Broca's area ( Zilles-2012 ). Functionally area 45 and area 44 are considered part of motor cortex, namely, the rostral part of ventral premotor cortex (PMVr in the human; F5 in the macaque) ( Matelli-2004 ).
The macaque equivalent is topologically, architectonically, and functionally similar ( Petrides-2012; Matelli-2004 ). As granular prefrontal cortex, it has no equivalent in the rat ( Zilles-2012 ).
Also known as: area 45
NeuroNames ID: 3531
