Ventral visual pathway

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Chapter 4 endnote 16, from How Emotions are Made: The Secret Life of the Brain by Lisa Feldman Barrett.
Some context is:

Your brain initiates your catch well before you consciously see the ball in the predicted location. You become aware of your intention to move your arm at about the same time as you become aware of seeing the ball in its current location, however, so it seems as if you see the ball and then move your arm to catch it.

This sequence explains why catching a baseball feels like a stimulus followed by a response. Your motor cortex initiates your catch (with prediction error from your dorsal visual stream) well before you consciously see the ball in the predicted location (with help from your ventral visual stream). Because the dorsal stream is a bit ahead than the ventral stream, it seems as if you see the ball, and then move your arm to catch it. This time difference is related to the illusion of conscious will.

The dorsal and ventral systems usually work together. Some people have an odd visual syndrome in which the dorsal system works correctly while V1 and the ventral system do not. It’s called “cortical blindness” or “blindsight.” An individual with this syndrome cannot see, subjectively speaking, but if you put an obstacle in his path, he walks around it.