The superior frontal sulcus is the groove that runs front to back along the top of each frontal lobe. It separates the superior frontal gyrus, next to the midline, from the middle frontal gyrus below it, and marks the outer edge of the superior frontal gyrus. At the back it starts near the superior precentral sulcus; in front it ends near the frontal pole. [1][2]
Seen from above: the superior frontal gyri are lit in blue either side of the midline, the middle frontal gyri in orange outside them, on both hemispheres. The groove runs where blue meets orange; the top (axial) slice button cuts across it. Drag to turn, pinch or scroll to zoom, tap any part to name it; .
A groove has no shape of its own; lit: the parts on either side of it. Lit: above, towards the midline, the superior frontal gyrus in blue; below, on the outer side, the middle frontal gyrus in orange. The superior frontal sulcus lies between the superior frontal gyrus and the middle frontal gyrus and marks the outer edge of the superior frontal gyrus. [1][2]
Its shape varies: in 50 MRI scans mapped into a standard brain space it was either one continuous groove or a chain of separate segments, and it often merged with neighbouring grooves on the superior and middle frontal gyri. [2]
What it does
A fold, not a working part. In a meta-analysis of eye-movement (prosaccade and antisaccade) imaging studies, activation converged most strongly at the junction of the precentral sulcus and the superior frontal sulcus, the site of the frontal eye field. [5]
The frontal eye field is described as lying around where the middle frontal gyrus meets the precentral gyrus, which is the back end of this groove. [6]
The dorsolateral prefrontal cortex is placed on the middle frontal gyrus, so on the lower bank of this groove; definitions of its exact borders differ. [7][4]
Size
The model has no shape for the superior frontal sulcus, so the groove itself is not measured here. Measured from the model instead: on the left hemisphere, the stretch where the superior frontal gyrus and the middle frontal gyrus come within 3 mm of each other fits in a box about 88 mm front to back, 64 mm top to bottom and 17 mm side to side (the box that stretch fits in, not the groove’s length along its bends or its depth). [8]
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.
