The inferior frontal gyrus
is a gyrus
of the frontal lobe
of the human brain. Its superior border is the inferior frontal sulcus
, its inferior border the lateral fissure
, and its posterior border is the inferior precentral sulcus
. Above it is the middle frontal gyrus
, behind it the precentral gyrus.
The inferior frontal gyrus can be subdivided into the following macroanatomical structures:
- Pars opercularis (cortex posterior to the ascending ramus of the lateral fissure)
- Pars triangularis (cortex between the ascending ramus and the horizontal ramus of the lateral fissure)
- Pars orbitalis (cortex inferior and anterior to the horizontal ramus of the lateral fissure)
The inferior frontal gyrus includes the following cytoarchitectonic areas:
The cytoarchitectonic areas very roughly correspond to the following macroanatomic structures: Brodmann area 44 to Pars opercularis, Brodmann area 45 to Pars triangularis, and Brodmann area 47 to Pars orbitalis. Brodmann area 44 corresponds to Broca's area (sometimes Broca's area is taken to encompass Brodmann's areas 44 and 45).