Binocular Rivalry
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: Joel Pearson at UNSW Sydney showed that imagining an image increases its subsequent dominance in binocular rivalry. People with aphantasia do not show this "imagery priming" effect or show it significantly weaker. The binocular rivalry method thus provides an objective test for aphantasia that is not based on self-reports. It measures whether visual imagination activates the perceptual system. This method has helped show that aphantasia is a measurable neurological phenomenon.
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Related Terms
Aphantasia 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.
Learn moreThe 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.
Learn moreMental 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.
Learn moreDo you have Aphantasia?
Take our VST-16 test and find out where you fall on the visualization spectrum.
To the VST-16 Test