Posterior transverse collateral sulcus

At a glance

English

Posterior transverse collateral sulcus

System

Brain and spinal cord

Region

Head

Side

Paired, left and right

About the posterior transverse collateral sulcus

The posterior transverse collateral sulcus is a minor furrow on the inferior, tentorial surface of the cerebral hemisphere, the face that rests on the tentorium cerebelli. It belongs to a set of short grooves associated with the collateral sulcus, the long sulcus that runs forwards on the underside of the occipital and temporal lobes. An anterior transverse collateral sulcus lies further forward, near the temporal pole; the posterior one lies at the back of the system, in the occipital lobe.

As its name says, it runs across, roughly at right angles to the long axis of the collateral sulcus, rather than along it. It lies in the region of the posterior end of the collateral sulcus, near the lingual gyrus on the medial side and the fusiform gyrus on the lateral side, and it may cut across or join the end of the collateral sulcus. Its length, depth and exact position vary considerably between brains and between the two hemispheres, and it may be absent or broken into pieces.

The cortex around it is part of the ventral occipital visual cortex, which lies close to the calcarine sulcus and the primary visual area and continues forward into the ventral visual stream used for recognising shapes, colours and objects.

The groove is used mainly as a landmark in detailed maps of the cortex, such as those used to divide the brain surface into regions on MRI. It is supplied by branches of the posterior cerebral artery.

Function and supply

Function

A surface landmark on the underside of the occipital lobe, bordering ventral visual cortex.

Blood supply

Occipital and temporal branches of the posterior cerebral artery.