Binocular Rivalry
Research
Definition
Binocular Rivalry is a visual phenomenon and test procedure where a different image is shown to each eye. Perception alternates between both images, influenced by mental imagination.
Detailed Explanation
Binocular rivalry occurs when a different image is presented to each eye. The brain cannot process both images simultaneously and alternates between perceptions. This phenomenon is used in aphantasia research: Pearson, Clifford & Tong (2008, Current Biology) showed that imagining an image increases its subsequent dominance in binocular rivalry. Keogh & Pearson (2018, Cortex) applied the method to aphantasia: people with aphantasia do not show this "imagery priming" effect or show it significantly weaker. The binocular rivalry method thus provides evidence that does not rely on self-report – robust mainly at group level; for classifying individuals the effect is too small (Monzel et al. 2025). It measures whether visual imagination activates the perceptual system. This method has helped show that aphantasia is a measurable neurological phenomenon.
Keywords
- binocular rivalry
- perception
- test
- Pearson
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Related Terms
- AphantasiaAphantasia is the inability to voluntarily create mental images. People with aphantasia cannot visualize faces, places, or objects in their mind's eye, although they can recognize and describe them. The term was coined by neurologist Adam Zeman in 2015.
- VVIQ (Vividness of Visual Imagery Questionnaire)The VVIQ is a standardized questionnaire for measuring the vividness of visual imagery. It consists of 16 items where participants rate their ability to visualize on a 5-point scale.
- Mental ImagesMental images are internal visual representations that arise without external stimuli. They enable seeing objects, scenes, or people before the "mind's eye," such as when remembering, dreaming, or planning.
External Resources
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