What do unconscious patients understand?

There has been a lot of media interest recently in work being conducted at Addenbrooke′s Hospital Cambridge with patients in a permanent vegetative state (BBC, 2008). It is becoming apparent that some patients, previously thought of as being completely unaware of anything, may have some understanding and awareness of their environment. In a few cases it has been shown that patients are completely aware of everything that is being said to them and retain the capacity for higher thinking, recalling memories and imagining. While the researchers stress that patients diagnosed as vegetative who retain some conscious awareness are in the minority, they are now using functional MRI to identify those in this position.