Imagine that your loved one, say, your brother, received an extensive brain injury. He lay in a coma for a long time, and finally “appeared” - the dream gives way to wakefulness, his hand pulls back, if you prick her, he is frightened by loud noises, etc. But it is not known whether he really woke up. His eyes are open, but they wander aimlessly. He cannot communicate, does not follow instructions, even such simple ones as “squeeze my hand” or “blink if you hear me”. Does your brother still live in his body?
Our concept of the preservation of self-consciousness can be reduced to the dictum of Descartes: "I think, therefore I exist." A person can resist multiple attacks: paralysis, memory loss, blindness, and language loss. But the
loss of awareness of what is
happening - the ability to consciously perceive the environment and respond to it - takes away something really fundamental.
A significant number of people leaving a coma, remain, sometimes for decades, in a vegetative state. Such patients show no obvious signs of awareness of their environment, who they are, or how they feel and perceive. It seems that they consist only of a tangle of reflexes. But family members sometimes still say that people who are dear to them are “somewhere inside”. For example, Paul Trembly, the doctors said that his son Jeff was in a vegetative state for 16 years. Paul worked out a ritual — load it weekly into a wheelchair and take it to the cinema, believing that Jeff can understand and enjoy the movies. Was this an attempt to wishful thinking?
By definition, the behavior of vegetative patients shows no signs of consciousness activity. But what if you carefully look at the activity of their brain? Is it possible to find evidence of consciousness in it? Adrian Owen, one of the world's leading researchers of impaired consciousness, described in an article in Scientific American how stunned he was by placing patient Kate in a scanner and showing her photos of her friends and family members. The activity in her brain was very similar to the activity of the intact brain of people who viewed images of their family members. It was a glimpse of evidence for consciousness.
But this is just a glimpse. The problem with
neuroimaging is that such photographs do not provide enough evidence of the similarity of the brain activity of patients with the brain activity of healthy people. It turns out that a tangible part of the mental activity of healthy people - even the one that we consider to be conscious - occurs automatically, without affecting the consciousness. Because of this, it is very easy to decide that consciousness is where it is not, whether it is vegetative patients or ourselves.
Owen had a hard time knowing this. At first, he was interested in activity in the brain areas of vegetative patients responsible for speech recognition, which arose in response to speech, and did not arise in response to other sounds. It soon became clear that the same, in fact, activity can be seen in healthy people who are unconscious under anesthesia - and in unconscious people this activity was just as strong. In order to truly probe the brain in search of consciousness, scientists needed to find a task that cannot be solved without the use of consciousness.
There is no clear scientific definition of consciousness, and the boundaries between consciousness and the unconscious are surprisingly blurred. For the most part, scientists agree that, most likely, mental processes are associated with such mental processes that are maintained constantly rather than disappear shortly after they appear, and include attention control focused on achieving the goal. Example: I will ask you a question, and if the answer is no, imagine that you are playing tennis, and if yes, imagine that you are walking around the rooms of your house. Is it true that your name is Mike?
It is difficult to imagine that such a task can be performed on reflexes. It requires you to understand the instructions, correctly answer the question and create some kind of picture in your mind, with simultaneous memory that tennis is associated with the answer “no”, and a walk through the house with the answer “yes”. At the same time, Owen and his colleagues found that about one in five vegetative patients was able to correctly answer such questions. The proof was based on the fact that thoughts about tennis do not involve the same areas of the brain as thoughts about walking around the house. Some patients were even able to use this method to transmit information about their condition. In one of the touching moments caught by the Air Force camera, Scott Routley was able to convey that he does not feel pain.
These tests, apparently, provide evidence of consciousness in a small, but tangible number of patients with a vegetative diagnosis. But what if most images of brain activity do not show the presence of consciousness? It is difficult to say what this means - because patients can be conscious, if at the same time they do not have one specific function that is necessary to complete the task. Perhaps they have ceased to understand the language, or their memory has deteriorated so that they cannot store instructions in it for long enough.
And the most difficult question: if patients like Kate, Jeff and Scott are aware of what is happening, what are they experiencing? Is consciousness a universal phenomenon that underlies our sensations, connecting them into a single meaningful interpretation that can be assessed from the outside? In this case, the consciousness of vegetative patients will be very similar to ours. But what if the nature of consciousness is fragmented and ephemeral, because then these patients can exist in a completely different state, existing somewhere on the threshold between sleep and reality. To understand the inner world of vegetative patients, scientists will have to go on a journey to the darkest corners of the science of mind.
Meanwhile, Paul Trembly takes his son to the movies. Photos of the brain taken by Owen and his colleagues showed that the activity of his brain while watching Hitchcock's short film looked organized and was similar to the brain activity of healthy people. For his father, Jeff remained Jeff. In an interview with Maclean's magazine, he admitted: “He’s different, but it’s still him, we’ve got used to the fact that this is Jeff. We love him the same way. ”