The researchers at Western University in London, Ont., released a paper Monday about a brain scanning technique that monitors the response of non-responsive patients to a shortened version of the movie, "Bang! You're Dead."
The study included a 34-year-old Canadian patient with a brain injury who has been unresponsive for 16 years.
Postdoctoral fellows with Western's Brain and Mind Institute brought healthy and brain-damaged participants into an MRI scanner and then displayed the Hitchcock movie about a five-year-old boy who finds his uncle's revolver, partially loads it with bullets, and plays with it in public.
Their study found the participants who watched the movie had common patterns of brain activity that strongly resembled those of healthy participants.
The research found the similarities in reactions from the frontal lobes and the posterior parietal portions of the brain — areas where reasoning and more complex processes occur.
Lead researcher Adrian Owen, a neuroscientist, said the findings suggest that one vegetative participant was both aware of and understood the movie. Another non-responsive participant didn't show the same level of response, he added.
The technique determined the 34-year-old patient could understand language, follow events as they unfold in time, lay down memories, experience emotions and follow plot changes, Owen said in an interview.
Owen is hopeful the research creates a method that will help detect whether a patient is conscious and whether they are able to think about what they're seeing and experiencing.
Once doctors know a person can understand a film, he said, it may allow neuroscientists to make additional efforts to determine the wishes of a patient.
"If you know a patient is aware, then you're going to behave differently," he said.
"As soon as the patient themselves can be included in decision-making, we can have a really big impact on their quality of life. That may be a big thing like 'What do you want your future to be?' ... or a small thing like 'What kind of television do you like to watch?' "
The neuroscientist said he hasn't decided how he'll adapt the movie technique to permit questions to be asked.
The researchers chose the Hitchcock movie because it had a high level of suspense that would draw out a wide range of brain responses, they said.
Owen said the decision to use a movie came partly because the father of the vegetative patient told him he'd taken his son to the movies for 16 years hoping he might be understanding something.
The researcher said it's important to distinguish between vegetative patients and patients in a coma.
A person in a vegetative state may be awake for periods of time but is often unresponsive and won't reply to attempts to communicate, he said, while a person in a coma isn't awake.
The research paper — titled "A common neural code for similar conscious experiences in different individuals" — was published in the Proceedings of the National Academy of Sciences. Lorina Naci and Rhodri Cusack of Western's department of psychology are listed as co-authors, along with Mimma Anello of the Schulich school of medicine and dentistry at Western.