Lingual gyrus

At a glance

English

Lingual gyrus

Latin (TA2)

Gyrus lingualis

System

Brain and spinal cord

Region

Head

Side

Paired, left and right

About the lingual gyrus

The lingual gyrus is a fold of cortex on the medial side of the occipital lobe, named for its tongue-like shape. It runs forwards from near the occipital pole, lying partly on the medial surface and partly on the inferior surface of the hemisphere, where it rests on the tentorium cerebelli.

Above, it is bounded by the calcarine sulcus, which separates it from the cuneus. Below and laterally, the collateral sulcus separates it from the fusiform (lateral occipitotemporal) gyrus. Anteriorly it narrows and passes into the parahippocampal gyrus of the temporal lobe, near the point where the calcarine sulcus joins the parieto-occipital sulcus and the isthmus of the cingulate gyrus comes down behind the splenium of the corpus callosum.

The upper part of the gyrus, forming the lower lip of the calcarine sulcus, belongs to the primary visual cortex (Brodmann area 17), which is marked by the white stria of Gennari in its cortex. Because the visual fields are inverted on the cortex, this lower bank receives signals from the upper half of the opposite visual field, carried from the lateral geniculate body by the lower fibres of the optic radiation through the temporal lobe (Meyer's loop). The rest of the gyrus is visual association cortex, which, with the fusiform gyrus, takes part in recognising colour, shapes and familiar scenes.

A lesion of the lower bank of the calcarine sulcus causes loss of the upper quarter of the visual field on the opposite side, a contralateral superior quadrantanopia. Damage to the lingual and fusiform gyri, usually from a posterior cerebral artery stroke, can cause loss of colour vision (cerebral achromatopsia) in the opposite half-field.

Function and supply

Function

Its calcarine bank is primary visual cortex for the upper half of the opposite visual field; the rest is visual association cortex concerned with colour, form and scene recognition.

Blood supply

Branches of the posterior cerebral artery, chiefly the calcarine artery, together with the posterior cerebral artery's inferior temporal branches.