Supramarginal gyrus
Gyrus supramarginalis
Desikan-Killiany · source label supramarginal · SMG
Eloquence
- Lies next to speech areas of the dominant hemisphere (usually left) and to sensory cortex; Sawaya's grading treats such regions as near-eloquent. (Sawaya et al. 1998)
What it does
- Part of the inferior parietal lobule; it arches over the posterior end of the sylvian fissure. (Rhoton 2002)
- In the dominant hemisphere (usually left) it belongs to the perisylvian language network, connected with frontal and temporal language areas through the arcuate fasciculus. (Catani et al. 2005)
Arterial supply
- Supplied by posterior cortical branches of the middle cerebral artery. (Tatu et al. 1998; Rhoton 2002)
Venous drainage
- Superficial cortical veins drain upward to the superior sagittal sinus or downward to the superficial sylvian veins. (Rhoton 2002)
Deficits if injured
- Lesions or stimulation in this region of the dominant hemisphere (usually left) can disrupt language; essential sites vary between individuals. (Ojemann et al. 1989; Catani et al. 2005)
Surgical relevance
- Resections near the inferior parietal lobule of the dominant hemisphere (usually left) are commonly guided by awake language mapping. (Sanai et al. 2008; Ojemann et al. 1989)
Brodmann areas (approximate): 40
On the template
Desikan-Killiany. Values describe the fsaverage template, not an individual or a population norm.
| Side | Label (as in source) | Area, cm² | Centroid MNI152, mm |
|---|---|---|---|
| left | supramarginal | 28.7 | -52, -38, 33 |
| right | supramarginal | 26.3 | 54, -31, 32 |
Area: pial surface of the fsaverage average, which is smoother than individual cortex. Volume: voxel count of the fsaverage aseg segmentation at 1 mm isotropic.
References
- Sawaya R, Hammoud M, Schoppa D, Hess KR, Wu SZ, Shi WM, et al.. Neurosurgical Outcomes in a Modern Series of 400 Craniotomies for Treatment of Parenchymal Tumors. Neurosurgery 1998;42(5):1044-1055. doi:10.1097/00006123-199805000-00054
- Rhoton AL. The Cerebrum. Neurosurgery 2002;51(suppl_4):S1-1-S1-52. doi:10.1097/00006123-200210001-00002
- Catani M, Jones DK, ffytche DH. Perisylvian language networks of the human brain. Annals of Neurology 2005;57(1):8-16. doi:10.1002/ana.20319
- Tatu L, Moulin T, Bogousslavsky J, Duvernoy H. Arterial territories of the human brain. Neurology 1998;50(6):1699-1708. doi:10.1212/WNL.50.6.1699
- Rhoton AL. The Supratentorial Arteries. Neurosurgery 2002;51(suppl_4):S1-53-S1-120. doi:10.1097/00006123-200210001-00003
- Rhoton AL. The Cerebral Veins. Neurosurgery 2002;51(suppl_4):S1-159-S1-205. doi:10.1097/00006123-200210001-00005
- Ojemann G, Ojemann J, Lettich E, Berger M. Cortical language localization in left, dominant hemisphere. Journal of Neurosurgery 1989;71(3):316-326. doi:10.3171/jns.1989.71.3.0316
- Sanai N, Mirzadeh Z, Berger MS. Functional Outcome after Language Mapping for Glioma Resection. New England Journal of Medicine 2008;358(1):18-27. doi:10.1056/NEJMoa067819
Related: postcentral gyrus, superior temporal gyrus, pars opercularis
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