Dichoptic

Dichoptic describes a method of presenting different visual stimuli to each eye. The term derives from Greek roots meaning two eyes (di) and vision (optic). In dichoptic experiments, the left and right eyes are shown distinct images or patterns, enabling direct manipulation of binocular input.

In vision science, dichoptic stimulation is used to study how the brain combines or competes between the two eyes. It is central to research on binocular rivalry, where different images presented to each eye lead to perceptual alternations between the two images. Dichoptic paradigms also explore binocular suppression, fusion, depth perception, and the mechanisms underlying amblyopia and other interocular imbalances.

Clinically, dichoptic methods have been developed for treatment and rehabilitation. Dichoptic training aims to reduce suppression of the weaker eye in conditions such as anisometropic or strabismic amblyopia by delivering complementary or differently weighted stimuli to each eye, often together with perceptual tasks. The goal is to encourage binocular cooperation and improve stereoacuity.

Common approaches to delivering dichoptic stimuli include traditional stereoscopes and haploscopes, red-green or red-blue anaglyph glasses, polarized filters, shutter glasses, and modern virtual reality or augmented reality head-mounted displays. These technologies allow precise control of luminance, contrast, and timing between the eyes, enabling rigorous experimental and therapeutic protocols.

See also: Binocular rivalry, binocular fusion, amblyopia, binocular vision.