Corpus: Inferior frontal gyrus

The inferior frontal gyrus is a large prominent cerebral cortex (gyrus cerebri) of the lower outer frontal lobe (lobus frontalis cerebri).

The inferior frontal gyrus is separated from the medial frontal gyrus by the inferior frontal sulcus and divided into 3 parts by the ascending horizontal and ascending anterior rami of the lateral sulcus:

• the pars orbitalis lying on the bony roof of the orbit
• the triangular "pars triangularis" and
• the pars opercularis as the frontal part of the operculum.

The partes triangularis et opercularis of the dominant cerebral hemisphere are the seat of the motor speech centre (Broca's area). This corresponds to areas 44 and 45 according to Brodmann.

• Illustration of the inferior frontal gyrus on the plastinate
• Brain Atlas