GROSS: Jon, I want to start with you. Would you describe the difference between who you were before the stroke and who you are now?
Mr. SARKIN: Yeah, before the stroke, I was a chiropractor, and I thought in a much more linear fashion about stuff. That's what doctors do, they think in a very organized, linear way where it's basically an algorithmic way of thinking.
Now, it's more a stream-of-consciousness, holistic, nonlinear way of thinking.
GROSS: And there's a difference that before the stroke, you had enjoyed sketching and painting, and after the stroke, you became, can we say a compulsive artist?
Mr. SARKIN: Yeah, before the stroke, I enjoyed it from a purely non-vocational point of view. Just, I enjoyed doodling on vacations. I enjoyed doodling while I was talking on the phone.
If we had a party at my house, sometimes I'd design the invitations, but never in my wildest dreams did I ever have a thought that I could somehow make this more vocational.
Now, obviously, it is. And I create art all the time because that's what I do, both from a professional standpoint and also a compulsive standpoint.
GROSS: Amy Ellis Nutt, what medical mysteries did you want to understand by writing this book about Jon, his stroke and how it transformed him?
Ms. AMY ELLIS NUTT (Author, "Shadows Bright as Glass"): There were a number of things. The first and most striking thing about Jon's case is that people who suffer identity disorders, from a stroke or a brain disease, are usually people who are unable to reflect on who they were before.
Jon is that rarest of individuals who was acutely aware and is acutely aware of what he lost and how he changed and the fact that he was a radically different man in body and soul.
So I was fascinated by this aspect of someone knowing that they are essentially two selves, a former self and a present self, and how that works and in essence what makes us who we are.
Is it memory? Is it emotion? Is it cognition? Is it personality? And I think all of those things play a part in Jon's story.
And coupled with that, I've always had an interest in sort of the philosophical issues of identity and consciousness, and it seemed to me that their stories paralleled beautifully in terms of philosophy and neuroscience's search for identifying where in the brain we can say identity rests and Jon's search to understand himself.
GROSS: So I'm going to ask you to describe for us, based on what you know, what parts of his brain were affected by the stroke?
Ms. NUTT: One thing that the scientists have discovered who have taken brain scans of Jon's brain is that his heart stopped twice after his stroke. So he has areas of the brain, all over the brain, that were deprived of oxygen. The primary damage was to his left hemisphere and, in particular, to the left side of the cerebellum.
What was really interesting in my research was learning about what scientists are now finding out with regard to the cerebellum. What some of the research into the cerebellum has shown is that it carries our associations with sensory systems, how we track movements in the world around us.
And part of the deficit, I think, that Jon has is that his relationship to the environment, to the world, is literally fresh every moment. It's unfamiliar. He experiences the world almost as if it's new every day. Objects around him -people, movement, what he hears, what he sees - are very much experienced in a kind of fresh way that's extraordinary for an artist.
GROSS: Now, that sounds lovely in one way, everything is fresh and new, but it also sounds like things might not have context or meaning, or there might be an inability to have a synthesis of what you're perceiving.
Ms. NUTT: One of the ways of looking at what happened to Jon - and this is a little bit simplistic - but because so much of the damage was to the left side of his brain, the side of the brain that scientists sort of call the interpreter; responsible for, you know, linear reasoning and routine, rehearsed processing. Whereas the right side of the brain is more intuitive, instinctual, it deals with novel situations that it then sort of passes over to the left side to figure out and make sense of.
In a way, Jon is stuck in the right hemisphere. It's through his right hemisphere, through the instinctive part, through the artistic part, through the part that responds to immediate sensations, that he's trying to work out the meaning of life, the meaning of his environment.
And because of that, it's a kind of constant - he'll be using different images in his art that he'll repeat over and over, a kind of perseveration, but in essence it's Jon's brain trying to figure out what it is and who he is.
Aristotle said that nature abhors a vacuum. If that's the case, then the brain absolutely abhors a mystery. It's always trying to figure out what's going on. When something is damaged, it tries to fill it in.
The brain essentially creates, constantly is creating stories, and that's what Jon is doing through his art. In essence, it's the story, the continuing story, his continuing journey of who he is.
GROSS: Amy, can I ask you to describe one of Jon's paintings or sketches that you think is a good illustration of what's going on in his mind?
Ms. NUTT: It's really difficult to do. You know, some of the iconic things in Jon's art - well, first of all repetition of words, and there's often a playfulness, a very witty use of language.
He brings in a lot of his literary background, things that he's read that he remembers, but then he'll bring in - it's fractured. It's pieces. And it's like he's constantly putting a puzzle together.
So he'll have, you know, cartoon faces with, you know, tubes running sort of in and out of their face, their mouth, their eyes, which is very reminiscent of the months that he spent in a hospital connected to wires and tubes. And then there's the use of constant - the cross-hatching, over and over and over, which is, you know, something that Jon has to keep doing.
He literally has to keep doing art. It's what defines him. It is who he is. And in a way, one of the most iconic things about Jon's art are the words - for instance the name Rauschenberg. And Jon explained it to me once. He really -first of all, he likes the artist very much. But he likes the word because he doesn't have to lift his pen off the page to write it.
That's how compulsive and important it is for him to do art, that even the moment it takes to lift your pen off the page to dot an I or to cross a T takes Jon away from who he is.