Thats not entirely true really. In the case of the 'blind spot' and peripheral vision, a lot is invented by the brain and filled in, but general vision is relatively true to the way our eyes are designed. What is intriguing though is the fact that there is a 500millisencond lag in between the eyes SEEING and the brain SEEING, suggesting that all vision is processed 'preconciously' and then enters our field of vision. What the processing is, who knows? Also, this fact suggests that we never actually 'see' anything in the present, its all half a second old. Weird.
Psychedelics, with the enhanced and changed neaural connections, might PERHAPS alter that crucial processing stage of vision, either lengthening or more likely, shortening it, so we get a 'clearer' picture of reality, with less brain-noise intefering. The trailing and flanging of imagery certainly suggests a 'backlog' and feedback cycle occurring in the visual cortex....