Supramarginal gyrus

The supramarginal gyrus (plural: supramarginal gyri) is a portion of the parietal lobe of the brain. It is one of the two parts of the inferior parietal lobule, the other being the angular gyrus. It plays a role in phonological processing (i.e. of spoken and written language)and emotional responses.

Gross anatomy

Relations

The supramarginal gyrus is horseshoe-shaped and caps the posterior ascending ramus of the lateral sulcus, lying just anterior to the angular gyrus. Anteriorly it merges with the inferior aspect of the postcentral gyrus.

Its superior margin is somewhat variable, and can either be bounded superiorly by the intraparietal sulcus, or by additional sulci within the inferior parietal lobule.

Arterial supply

The main blood supply is via the middle cerebral artery (MCA).

Variant anatomy

The inferior end of the postcentral gyrus can be partitioned to form an accessory presupramarginal gyrus posteriorly .

Related pathology

Damage to the right-sided supramarginal gyrus may result in emotional egocentricity bias.