Some people who are cortically blind can still 'see' — without knowing it

Patients with damage to the brain's primary visual cortex report seeing nothing in part of their vision, yet when forced to guess where an object is, they point to it far more often than chance allows. Their eyes and lower visual pathways still register the world; only conscious awareness of it is missing.

— Lawrence Weiskrantz, Blindsight: A Case Study and Implications — Oxford University Press, 1986
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