hemispatial

Hemispatial is an adjective used in neuroscience and psychology to describe phenomena related to the spatial aspects of perception, attention, and action that are distributed across the brain’s hemispheres. The concept encompasses how spatial information is processed differently by the left and right hemispheres and how this lateralization influences behavior and cognition.

In practice, hemispatial processing is investigated through various lines of evidence. One well-known example is hemispatial neglect, a neurological syndrome that typically follows damage to the right parietal cortex and results in reduced awareness of stimuli on the left side of space, including the left side of the body. In healthier individuals, a mild leftward bias known as pseudoneglect is often observed in simple spatial tasks, such as line bisection, reflecting hemispheric asymmetries in attention networks.

Researchers study hemispatial processing using behavioral tasks and neuroimaging methods. Tasks like line cancellation, line bisection, and visual search probe how attention to space is distributed, while imaging techniques map activity in parietal, frontal, and temporal regions during spatial tasks. This field also intersects with broader topics of hemispheric asymmetry and lateralization of function, including visuospatial abilities and language.

Understanding hemispatial processing has implications for models of attention and perception and for clinical approaches to rehabilitation after brain injury. It helps explain why spatial abilities can vary across individuals and how the brain organizes space across its two hemispheres.

See also: hemispheric asymmetry, spatial neglect, lateralization.