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Aphantasia review challenges theory that imagination runs through visual cortex

Research on people who cannot form conscious mental pictures suggests imagery emerges from coordinated brain networks, with the primary visual cortex playing a supporting role.

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Owen Mercer
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Consciousness and Cognition

A review published in Consciousness and Cognition is challenging the influential “backward-seeing” theory of mental imagery, which holds that imagination is ordinary vision running in reverse through the primary visual cortex.

The review, by Derek Arnold, Loren Bouyer, Blake Saurels and Samuel Schwarzkopf, draws on brain scans, stimulation studies, aphantasia research and clinical cases. It argues that conscious imagery emerges from coordinated activity across regions including the frontal cortex, fusiform gyrus and areas involved in planning, rather than from a single visual-processing centre.

Aphantasia describes a lifelong inability to form conscious mental pictures. Some people also report reduced inner sound, smell, taste or touch. The review links the condition to weaker communication between relevant brain regions, while noting that its presentation varies between individuals and does not imply an absence of imagination.

Evidence against the visual-cortex theory includes patients who retained the ability to visualise after extensive damage to that region. Other studies found that temporarily quieting the primary visual cortex could make imagery more vivid, suggesting it may modulate mental images without creating the conscious experience itself.

The authors say the network account remains provisional and that there is no objective diagnostic test for aphantasia. They call for assessment based on converging evidence from self-reports, behaviour and brain measurements, while leaving open questions about the condition’s development, genetic basis and response to training.

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