Superior frontal sulcus
Sulcus frontalis superior
A long groove on the outer surface of the frontal lobe that separates the superior frontal gyrus from the middle frontal gyrus.
At a glance
- English
- Superior frontal sulcus
- Latin (TA2)
- Sulcus frontalis superior
- System
- Brain and spinal cord
- Region
- Head
- Side
- Paired, left and right
About the superior frontal sulcus
The superior frontal sulcus is one of the two main longitudinal furrows on the lateral surface of each frontal lobe. It runs from front to back roughly parallel to the upper margin of the hemisphere, a couple of centimetres from the midline. Above and medial to it lies the superior frontal gyrus, which continues over the edge onto the medial surface; below and lateral to it lies the middle frontal gyrus.
At its posterior end the sulcus usually meets the precentral sulcus at a right angle, a junction that is one of the most reliable landmarks on the frontal lobe and is easy to recognise on MRI. Forwards it fades out before the frontal pole. It is often interrupted by small bridging gyri, so it may appear as two or three segments rather than one continuous groove, and its pattern differs between the hemispheres and between individuals.
A sulcus has no function of its own, but the cortex lining and flanking it does. The posterior part of the superior frontal gyrus contains premotor cortex and, on its medial side, the supplementary motor area, which help plan and sequence movements. The human frontal eye field, which drives voluntary eye movements, lies close to where the superior frontal and precentral sulci meet. Further forwards, the cortex on either side belongs to the prefrontal areas involved in working memory and attention.
Its blood supply is shared. Branches of the anterior cerebral artery reach over the upper margin to supply the superior frontal gyrus, while branches of the middle cerebral artery supply the middle frontal gyrus, so the region lies near the watershed between these two territories and can be affected in border-zone infarcts. Neurosurgeons use the sulcus as a corridor to reach the frontal horn of the lateral ventricle with little damage to cortex.
Function and supply
- Function
- A surface landmark separating the superior and middle frontal gyri; the flanking cortex serves movement planning, voluntary eye movement and working memory.
- Blood supply
- Anterior cerebral artery branches to the superior frontal gyrus and middle cerebral artery branches to the middle frontal gyrus.
Anthromica
See the superior frontal sulcus where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
