Scar tissue has no character. It's not like skin. It doesn't show age or illness or pallor or tan. It has no pores, no hair, no wrinkles. It's like a slip cover. It shields and disguises what's beneath. That's why we grow it; we have something to hide.
Don't separate the mind from the body. Don't separate even character - you can't. Our unit of existence is a body, a physical, tangible, sensate entity with perceptions and reactions that express it and form it simultaneously. Disease is one of our languages. Doctors understand what disease has to say about itself. It's up to the person with the disease to understand what the disease has to say to her.
Whatever we call it - mind, character, soul - we like to think we possess something that is greater than the sum of our neurons and that animates us.