Imageless imagery in aphantasia revealed by early visual cortex decoding.
Current biology : CB February 3, 2025 Shuai Chang, Xinyu Zhang, Yangjianyi Cao et al.
Activity in the primary visual cortex is thought to be closely linked to conscious visual experience, including mental imagery. In people with aphantasia, who lack visual imagery entirely, researchers examined brain activity during attempts to imagine. Neural patterns representing imagined content could be decoded equally well in both groups, but in aphantasia the signals were located on the same side of the brain as the stimulus and could not be matched to perceptual brain patterns. Additionally, the brain response to actual visual input was weaker in aphantasia. These findings suggest that imagery-related representations exist in primary visual cortex even without conscious visual experience, challenging the assumption that such activity necessarily produces sensory qualia.