Recent experiments by Beatrice de Gelder of Tilburg University
in the Netherlands showed that a blind man in Switzerland could
respond to the visual world without his conscious awareness.
“TN,” as he is known, has a unique condition. His occipital
lobe, the part of the brain responsible for seeing, was damaged
by two strokes, but his eyes still function normally. When he
was asked to navigate past a series of obstacles, he responded
successfully. The researchers ruled out auditory or other non-
visual perception. Apparently, TN was using a subconcious type
of vision. He could not form an image in the conventional sense.
“Blindsight” is the ability to see at the subcortical level,
where images are processed by the amygdala and other primitive
parts of the brain. As the New York Times put it: “The brain has
a primitive, subconscious visual system working in tandem with
our conscious visual sense.” Other experiments have shown that
blind-seeing patients also respond emotionally to social signals
like angry faces,