parietooccipital

Parietooccipital describes the region of the cerebral cortex at the boundary between the parietal and occipital lobes, typically on the medial (inner) surface of the hemisphere. The boundary is marked by the parietooccipital sulcus, a groove that separates the precuneus in the parietal lobe from the cuneus and adjacent occipital cortex. The parietooccipital area therefore encompasses parts of the precuneus and posterior occipital cortex that are adjacent to the sulcus.

Functionally, this region participates in visuospatial processing and integration of visual information with spatial and motor planning. The precuneus has roles in visuospatial imagery, self-referential processing, and episodic memory; the surrounding occipital cortex contributes to higher-order visual perception.

Clinically, lesions or dysfunction in the parietooccipital region can impair visuospatial attention and perception and may contribute to optic ataxia, hemispatial neglect, or Balint-type syndromes when bilateral. In imaging and neurosurgical contexts, the parietooccipital boundary serves as an anatomic landmark for planning approaches to the posterior cortex; functional MRI studies often examine activity in this region during visual and spatial tasks. The term is primarily descriptive, reflecting a boundary rather than a single discrete anatomical structure.