Retinotopinen

Retinotopinen is the term used to describe the retinotopic organization of the visual system, in which spatial locations on the retina are represented by spatially corresponding locations in the brain. This topographic mapping is a fundamental organizational principle of the early visual pathway, extending from the retina through the lateral geniculate nucleus (LGN) to the primary visual cortex (V1) and beyond into higher visual areas. In primates, neighboring retinal points are represented by neighboring neurons in V1, and the arrangement is often illustrated as a polar-angle map overlaid with an eccentricity map. The fovea, a small central retinal region, is disproportionately represented in cortex—a phenomenon known as cortical magnification.

Retinotopy is typically studied by presenting visual stimuli that separately probe polar angle and eccentricity, or by functional imaging methods such as fMRI that track phase-encoded responses to rotating wedge or expanding ring stimuli. The resulting maps reveal systematic, continuous retinotopic organization across visual areas, though the precision and extent of retinotopy decline in higher visual areas.

Developmentally, retinotopy is established prenatally and refined after eye opening, with experience shaping receptive fields during critical periods. Adult retinotopy is robust but can exhibit limited plasticity after damage to the retina or cortex.

Retinotopinen underpins accurate spatial perception, spatial attention, and visual field localization, and serves as a foundational concept in studies of vision, neuroimaging, and neurological disorders affecting the visual system.