The superior frontal gyrus is the top of the three horizontal ridges on each frontal lobe: it runs from front to back along the upper edge of the hemisphere, beside the deep groove between the two halves of the brain, and makes up about a third of the frontal lobe. [1][2]
The 3D brain needs JavaScript. The text below still says where the superior frontal gyrus is and what it does.
Slice
Opens cut by a top (axial) slice through the superior frontal gyrus. Drag to turn, pinch or scroll to zoom, tap any part to name it; .
The outer surface of the frontal lobe has four gyri: the precentral gyrus, directly in front of the central sulcus, and three horizontal ones ahead of it, the superior, middle and inferior frontal gyri. [2]
It is bounded on its outer (lateral) side by the superior frontal sulcus, which separates it from the middle frontal gyrus below. [1][3]
It wraps over the top edge onto the inner (medial) surface that faces the other hemisphere; that medial portion is often called the medial frontal gyrus. [1]
Behind it lies the precentral gyrus, the motor strip; the frontal eye field sits just behind its outer back part, where the middle frontal gyrus meets the precentral gyrus. [2][1][4]
What it does
In fMRI experiments it is active during self-awareness, working with the sensory systems; its medial portion is active when people judge traits about themselves. [1]
It is linked to language, in particular starting speech spontaneously: the frontal aslant tract joins it to Broca’s area in the inferior frontal gyrus, and the two are wired in both directions. [1]
It may take part in executive functions such as self-monitoring, working memory, organisation and planning: in a 2006 study, people with damage to the left superior frontal gyrus did worse on working-memory tasks, most of all when the damage was in its outer, back part (mostly Brodmann area 8, in front of the frontal eye field). [1]
In a 1998 report by Itzhak Fried, electrical stimulation of a patch about 2 cm by 2 cm on the left superior frontal gyrus made a person laugh every time, with a feeling of merriment, and each time she gave the laughter a different outside reason. [1]
Connections
The frontal aslant tract runs from it down to Broca’s area in the inferior frontal gyrus; the two regions form a reciprocal network. [1]
Other names
SFG, also called the marginal gyrus; its medial portion, on the surface facing the other hemisphere, is the medial frontal gyrus. [1]
Size
On this model the left superior frontal gyrus measures about 116 mm front to back, 78 mm top to bottom and 32 mm side to side (the box it fits in, not its volume); the right one is its mirror image. [5]
Centre of the left superior frontal gyrus compared with the centre of the left middle frontal gyrus: 7 mm further back, 6 mm higher, 18 mm closer to the midline; 20 mm apart in a straight line. [5]
Centre of the left superior frontal gyrus compared with the centre of the left precentral gyrus: 43 mm further forward, 21 mm closer to the midline; 48 mm apart in a straight line. [5]
Facts describe anatomy and normal function only. The 3D model is the adult male BodyParts3D brain (credits and licence); real brains vary in size and shape, so its measurements describe one model, not anyone’s brain.