Trace of Thought Is Found in ‘Vegetative’ Patient

Scans show brain activations in, above, a healthy person as he answers “yes” or “no” to a question and, below, in someone whom doctors have deemed to be in a vegetative state.

“Physicians and society are not ready for ‘I have brain activation, therefore I am,’ ” Dr. Ropper wrote. “That would seriously put Descartes before the horse.”