Thursday, January 21, 2016

To see or not to see

A lot involved there...
If you are interested in blindness or vision in general, you might want to pick up a book called CRASHING THROUGH by Robert Kurson (Amazon).

This book follows the life of a guy named Mike May, who was blinded by a chemical explosion when he was three. His mother mainstreamed him and he learned to be fiercely independent, traveling the world with a cane and/or dog, starting businesses, skiing at the championship level, even serving in the CIA for two years, and in Ghana as a volunteer. He was quite the "ladies man," apparently, and finally married and had two sons.

In a chance moment, his wife's eye doctor hooks him up with another ophthalmologist who had performed an extremely rare stem cell transplant in six people--an operation open to only those with chemical burns of the cornea or a rare genetic disease called Stevens-Johnson Syndrome (blisters all over the body).

The doctor thinks Mike May could regain vision of some sort with the procedure--but there are big risks. First it only has a 50-50 chance of working. Even it it did work, what kind of vision he would get would be unknown and it could disappear in a second at any stage of his life. He also would have to take anti-rejection drugs that have severe potential side efx, including cancer.

A friend finds some accounts of people who had regained vision--and they found the world "drab" and were very depressed.

Eventually, he decides to try it--as he put it, not to regain vision but to see what vision is like--another adventure.

He has the two-part surgery, the first part to implant the cells around the burned and useless cornea and let them throw off  "daughter cells" for a few months to protect the second donor cornea.

When the bandages come off, brilliant light cascades in, shocking him. He tries to see his wife for the first time, but her face means nothing--she is a pink blob. He finds he can see colors OK, and motion...when something goes into motion, he can then "see" it--otherwise he cannot distinguish objects and people.

At the point, some researchers hook up with him and do a special MRI that shows brain activity in response to images--they put him in the tunnel and show him faces...no brain activity in the portion of the brain that recognizes faces, the same for objects... Colors and motion are OK.

They explain to him that seeing is mostly dependent on the brain and the info the brain accumulates about context and other attributes of things, starting at birth when babies touch and mouth everything they see, logging in this info. He had done this as a baby, but when the explosion took place, come neurons repurposed themselves to other tasks in the brain and were not going to help him "see" certain things.

He considers dumping the anti-rejection drugs and letting the new cornea get rejected. It takes so much work to consciously log in all the info over again--he memorizes clues about things--all flight attendants wear the same uniform, OK, got that. He keeps at it--although he does have a bad rejection episode.

Eventually, he brings his real talents to the fore--echo sounding, other sounds, smells, etc. He keeps the vision part but makes it secondary.

May is human--so I caution you that parts of this are sort of creepy or at least I thought so. One reason he wants vision, for example, is to go to topless beaches. When he finally does--he can only see the superstructure of women if they have on a brightly colored top. Irony!

I am missing sight in one eye and have found weird brain compensations and changes--this was fascinating to me.


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