Precuneus

The precuneus is the portion of the superior parietal lobule on the medial surface of each brain hemisphere.

It is located in front of the cuneus (the upper portion of the occipital lobe).

The precuneus is bounded in front by the marginal branch of the cingulate sulcus, at the rear by the parietooccipital sulcus, and underneath by the subparietal sulcus.

It is involved with episodic memory, visuospatial processing, reflections upon self, and aspects of consciousness.

The location of the precuneus makes it difficult to study.

Furthermore, it is rarely subject to isolated injury due to strokes, or trauma such as gunshot wounds.

This has resulted in it being "one of the less accurately mapped areas of the whole cortical surface".

While originally described as homogeneous by Korbinian Brodmann, it is now appreciated to contain three subdivisions.

It is also known after Achille-Louis Foville as the quadrate lobule of Foville.

The Latin form of praecuneus was first used in 1868 and the English precuneus in 1879.