While the study participants watched the film, researchers monitored their brain activity by functional magnetic resonance imaging (f MRI).
All 12 healthy participants showed similar patterns of activity, particularly in parts of the brain that have been linked to higher cognition (frontal and parietal regions) as well as in regions involved in processing sensory information (auditory and visual cortices).
Bjorn Merker, an independent neuroscientist in Stockholm, Sweden, argues that the brain stem supports an elementary form of conscious thought in infants with hydranencephaly.
Insects do not have consciousness in the usual sense because they lack the brain capacity for thought and understanding.
Neural systems that regulate attention serve to attenuate awareness among complex animals whose central and peripheral nervous system provides more information than cognitive areas of the brain can assimilate.
In the future, he would like to see results from more people in non-responsive states, and proof that specific features of the film, such as foreshadowing, relate to brain activity patterns that are similar in healthy people and those in vegetative states.
Owen says that the team has scanned many other people as they watched films, including many in vegetative states, and he hopes that other clinicians can adopt the method.
Moreover, he says, his discovery could help to improve the lives of patients who are unable to express their wishes.
Ever since the 34-year-old man lost consciousness at age 18 after being assaulted, his father has taken him to the cinema every Wednesday.
One behaviourally non-responsive person, a 20-year-old woman, showed patterns of brain activity only in sensory areas.
But another person, a 34-year-old man who has been in a vegetative state since he was 18, had patterns of brain activity in the executive and sensory brain areas, similarly to that of the healthy subjects.
Naci and her colleagues thought that showing them movies would make the test simpler.
“It is a stimulus that engages attention naturally, and it’s impossible not to follow — especially when you have an engaging movie from a masterful director like Hitchcock,” she says.
Within an attenuated system of awareness, a mind might be aware of much more than is being contemplated in a focused extended consciousness.