If I were to communicate with a dead Elvis Presley, there are several things I would want to know. Did he really work for the FBI? Did he die naturally or was he murdered? But more importantly I would want information that could be verified, information that I could not have known without his help, that can be checked so I know it really is him. I’d want evidence.

The national press is currently awash with stories about the fact that Rom Houben, a Belgian who has been in a coma for 23 years, cannot in fact communicate via a speech therapist and typewriter, despite initial reports he could.

The media became excited by the idea of Houben typing out thoughts while the therapist "guided his hand". These thoughts included statements claiming he felt "powerlessness. Utter powerlessness." In other words, sentiments that an observer would easily guess, and that turned out to be from the therapist rather than Houben himself.

Houben’s neurologist, Dr Steven Laureys never publicly supported these stories, but interestingly he is part of a team working with researchers at The University of Cambridge’s MRC and Cognitive and Brain Sciences Unit who have recently shown that some patients in a vegetative state can communicate, but by other means.

Dr Adrian Owen and Dr Steven Laureys have discovered that a different patient in a vegetative state for five years can communicate if their brain is scanned and they think of ‘tennis’ to answer ‘yes’ to a question and ‘home’ for ‘No’.

What makes this conclusion more credible is that the patient was asked specific questions about his family and these answers were interpreted by a strict protocol measuring brain activity eventually giving a ‘yes’ or ‘no’.

When communication and consciousness are entwined, questions unique to a personality are the only thing that can differentiate between knowledge from another source and fabricated information from human imagination.