Synesthesia
Neuroscience
Definition
Synesthesia is a neurological phenomenon where stimulation of one sense automatically triggers experiences in another sense. For example, letters may be perceived as colors.
Detailed Explanation
Synesthesia refers to the involuntary linking of different sensory perceptions, such as "seeing" colors when hearing music or "tasting" words. Approximately 4% of the population has some form of synesthesia. The most common forms are grapheme-color synesthesia (letters/numbers trigger color sensations) and sound-color synesthesia. Synesthesia is the opposite of aphantasia in that it represents excessive sensory coupling. Interestingly, aphantasia and synesthesia can occur simultaneously: a person might have synesthesia for sounds but be unable to generate visual representations. Neuroscientific research shows increased connectivity between sensory areas in synesthetes, while aphantasia has so far mainly been associated with an altered coupling between prefrontal and visual networks (Milton et al. 2021, doi:10.1093/texcom/tgab035).
Keywords
- synesthesia
- sensory perception
- color hearing
- sensory coupling
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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.
- 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.
- Visual CortexThe visual cortex is the region of the cerebral cortex that processes visual information. Located in the back of the head (occipital lobe), it is responsible for both seeing and visual imagination.
External Resources
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