Neurologist Oliver Sacks' new book focuses on his own eye tumor, loss of vision

From Fresh Air with Terry Gross on WHYY:

Neurologist and writer Oliver Sacks has spent his career examining patients struggling to survive with a wide range of neurological conditions: Tourette's syndrome, autism, Parkinson's, musical hallucinations, Alzheimer's disease and phantom-limb syndrome.

But in his latest book, The Mind's Eye, Sacks turns the tables on himself. He writes about being diagnosed with a rare eye tumor and the subsequent total loss of vision on his right side. He also shares the case studies of other people who learned to compensate and adapt after neurological disorders robbed them of their ability to recognize faces, read or see.

Sacks tells Terry Gross that since the loss of half of his vision — and by extension, his stereoscopic vision — he has had to learn to adapt to a world that appears to be entirely flat.

"Steps and curbs just looked like horizontal lines on the ground. There was no sense of near and far. No sense of depth. Sometimes what was near and what was far would be conflated," he recalls. "Going down stairs was particularly dangerous. I had to sort of feel out each stair with my foot because it looked flat. And sight is so dominant that sometimes [my] eye would argue with the foot and say 'Look. It's flat and that's that. You don't have another step.'"

To compensate, Sacks tries to keep objects to the left of his visual field and has rearranged the furniture in his house. But he's also found that his other senses helped him compensate to his newly flattened world.

"I've adapted to this somewhat, but only by being very conscious of it," he says. "I became more adept in using other clues: shadow, shading, perspective, occlusion. But the absence of real depth, the absence of stereo, is still absolute."

Sacks is the author of 10 books, including An Anthropologist on Mars, Musicophilia and The Man Who Mistook His Wife for a Hat. He is a professor of neurology and psychiatry at Columbia University Medical Center and the first Columbia University artist.