Dr. Oz explains that the stroke Jill suffered is actually not all that common. In about 85 percent of strokes, something—such as plaque—from the heart or a major artery gets dislodged and travels up to the brain. It gets stuck there and blocks off part of the brain from receiving blood. The cells that are denied blood eventually shrivel and die. In these cases, the patient will not recover in a way similar to Jill's experience.
How was Jill's stroke different? Dr. Oz says her stroke, called an arteriovenous malformation, was almost like a charley horse. Like a varicose vein, an artery became raised in her brain, and eventually popped and bathed her brain in blood. "That blood is toxic to the brain tissue," he says. "It also puts pressure on it. It causes spasms of the arteries around it, and this tissue begins to die."
Jill was able to recover from her stroke because not all of the tissue died—islands of healthy cells survived. "There must have been enough islands of cells alive to rebuild the plasticity of the brain," he says. "We didn't think the brain could recover until recently, but it turns out the brain does recover. All of the organs do. You just can nourish it and nurture it."
The left and right sides of everyone's brain are responsible for different tasks. The left is responsible for language and logic, while the right is more visual and processes information intuitively. The reason Jill couldn't speak—but understood from her colleague's soothing inflexion that he was sending help to her—is because the hemorrhage occurred on the left side of her brain.