Intraparietal

Intraparietal refers to the structures associated with the intraparietal sulcus (IPS) of the parietal lobe in the brain. The intraparietal sulcus is a prominent groove that runs across the parietal cortex, separating the superior from the inferior parietal lobules. Within and around the IPS lie several functionally distinct cortical areas that are interconnected with occipito-temporal and frontal regions, supporting a range of sensorimotor and cognitive processes.

In primates, including humans, the IPS contains multiple intraparietal areas such as the lateral intraparietal area (LIP), anterior intraparietal area (AIP), medial intraparietal area (MIP), and caudal intraparietal areas like CIP. These regions contribute to visually guided actions and perception: LIP is associated with eye movements and attention, AIP with hand shaping and grasp planning, and MIP with reaching movements. CIP and related areas contribute to depth and object property processing. Human IPS is also implicated in visuospatial attention, representation of numerical magnitude, tool use, and multisensory integration.

Clinical and research relevance: disruptions to the intraparietal regions can produce deficits in visually guided actions, such as optic ataxia or hemispatial neglect. The IPS is a major focus of neuroimaging and neurophysiology studies aiming to understand how vision, attention, and action are coordinated. Techniques used to study its function include functional MRI, electrophysiology in nonhuman primates, and noninvasive brain stimulation like TMS.

Overall, the intraparietal region plays a central role in transforming sensory information into coordinated actions and spatial cognition.