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The Wisdom of Psychopaths
In this engrossing journey into the lives of psychopaths and their infamously crafty behaviors, the renowned psychologist Kevin Dutton reveals that there is a...
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At the heart of science are judicious observations and measurements. This reality presupposes that something can be measured. But how can consciousness—the notorious ineffable and ethereal stuff that can’t even be rigorously defined—be measured? Recent progress makes me optimistic.
Consider a problem of great clinical, ethical and legal relevance, that of inferring the presence of consciousness in severely brain-damaged patients. Often the victims of traffic accidents, cardiac arrests or drug overdoses, such patients have periods when they are awake, and they may spontaneously open their eyes. On occasion, their head turns in response to a loud noise, or their eyes might briefly track an object, but never for long. They might grind their teeth, swallow or smile, but such activities occur sporadically, not on command. These fragmentary acts appear reflexlike, generated by an intact brain stem.
As many as 25,000 such “vegetative” patients in hospices and nursing homes hover for years in this limbo, at a steep emotional and financial cost. The extent of the damage and the persistent absence of purposeful behavior usually leave little doubt that consciousness has fled the body for good. Terri Schiavo was such a case, alive but unconscious for 15 years before her court-ordered death in 2005 in Florida.
Even worse, though, is the possibility that some of these patients may experience some remnants of consciousness, unable to communicate their feelings of discomfort or pain, agonizing thoughts or poignant memories to the outside world. Until recently, nothing could be done to diagnose when an awake mind was entombed inside a damaged brain.
Technology has come to the rescue with the demonstration—by Adrian M. Owen and his research group at the University of Cambridge—of awareness in an unresponsive patient with the aid of functional brain imaging. The patient, a young woman who sustained massive head injury as a result of a car accident, fulfilled all criteria for the vegetative state. In particular, she was unable to signal with her eyes or hands in response to commands. Owen placed the noncommunicative patient in a magnetic scanner and asked her to imagine playing tennis or to imagine visiting the rooms in her house. You and I have no trouble doing these tasks. In healthy volunteers given these instructions, regions of the brain involved in motor planning, spatial navigation and imagery light up. They did likewise in the unfortunate woman. Her brain activity in various regions far outlasted the briefly spoken words and in their specificity cannot be attributed to a brain reflex. The pattern of activity appeared quite willful, indicating that the patient was, at least occasionally, conscious but unable to signal this fact, more effectively cut off from her loved ones than any prisoner in solitary confinement. It may be possible to develop this technique into a kind of two-way radio between the patient and the rest of humankind.
It remains an open question how prevalent such a tragic condition—aware yet utterly uncommunicative—is. Brain scans of 17 vegetative patients have turned up only one other non-responsive patient with such a voluntary brain signal. Keep in mind, however, that absence of evidence is not evidence of absence and that the presence of consciousness will depend on the exact nature of the brain injury. The point I want to emphasize is that Owen and other researchers like him are developing scanning tools to spot consciousness without any external behavior.
Betting on Consciousness
The ultimate judge of any conscious feeling is the subject itself. This truism is used in everyday life: Can you see the angry face? Well, if you can’t, then you’re not conscious of it. This seductively simple strategy has drawbacks; in particular, people disagree on what exactly “consciously seeing” is if the face was only briefly flashed on a computer display screen. (Did you see any part of a face? Did you think you saw something like a face?) To get around this problem, neuropsychologists Navindra Persaud, Peter McLeod and Alan Cowey of the University of Oxford exploit gambling.
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9 Comments
Add CommentThis is a key finding as to understanding consciousness. Indeed, much seems to be going on, unfortunately the wrong way, when studying the latter and claiming that patients under anesthesia are "unconscious" and plowing along with much hypotheses and theories! In fact, these patient are in a state of "faintness" but NOT unconsciousness!
Reply | Report Abuse | Link to thisCheck this out:
& Stuart Hameroff, an anesthesiologist and director of the Center for Consciousness Studies at the University of Arizona, argues that the highest function of lifeconsciousnessis likely a quantum phenomenon too. This is illustrated, he says, through anesthetics. The brain of a patient under anesthesia continues to operate actively, but without a conscious mind at work. What enables anesthetics such as xenon or isoflurane gas to switch off the conscious mind?
http://xenophilius.wordpress.com/2009/01/16/theory-and-evidence-for-natural-quantum-computing-as-the-cause-of-consciousness/
The subject under discussion is not consciousness. It is communication. Do animals lack consciousness? Do beliefs indicate consciousness of another dimension? We prefer to accept our experience of awareness as consciousness and include any idea as a perception of consciousness. Descartes was wrong. Awareness identifies self. It is evidence of perception, limited by the ability to perceive.
Reply | Report Abuse | Link to thisIf we could truly communicate we might be able to understand the difference between reality and belief.
There are degrees of communication. There has been no evidence of degrees of consciousness.
Christof Koch is a very clever scientist and has revealed amazing things about the conscious mind and brain. But he's committed, seemingly, to one particular ontology and might be missing the actual underlying reality. Still I agree with his basic conclusion - we need better ways of measuring consciousness. Contra the commet above there are degrees of consciousness - as subjective self-examination revealed ages ago. Now let's find a way of objectively measuring that.
Reply | Report Abuse | Link to thisProf. Tim Wilson of Virginia is quoted often about a statistic that
Reply | Report Abuse | Link to thistalks of the rates of information processing (absorption) by brain:
brain processes about 40 bits of info per second consciously
whereas the unconscious processing is eleven million bits per second.
These numbers were given in his 2002 book "Strangers to Ourselves."
Even if the actual numbers are approximate, the enormous difference in
the order of magnitude is highly significant as it can explain several
things that are related to the function of brain - e.g. dream content,
feelings of deja vu, intuition, some decision making, sudden answers
coming to the mind to problems well-churned in the brain earlier etc.
When I asked for a clarification as to how he arrived at these
numbers, Prof Wilson responded to me as follows:
"I actually got those figures from an interesting book by
Norretranders called The User Illusion. I think we need to be careful
about using these numbers too literally; it is difficult to tell how
many independent inputs the brain can process. Nonetheless I think
the general point is true, namely that the amount of information we
can process exceeds what we can attend to consciously."
Later I found that Dr. Tor N�rretranders book 'User Illusion" was a
translation of his original Danish version published in 1991! And I
do not know how Norretranders arrived at those numbers almost twenty years ago!!
Prof. J. A. Bargh's and others' work at New York University in 1996 on
the influence of subliminal information on the later behavior of
students is well-known. We have many recent publications on the
significance of unconscious in decision making. But how can one go
about quantifying the amount of info. absorbed (processed) by the
conscious and unconscious brain activity?
Can Prof. Christof Koch throw light on this please and
also cite a reference regarding the information processing speeds of
brain consciously and unconsciously?
thanks and regards
The low bit rate seems a bit odd in my mind. Visual consciousness surely represents a large fraction of the information input and is at least in the millions of bits for any one gestalt. 10-40 bits of abstracted information I can believe but the contents of primary consciousness seems very detailed. The difference between what can be measured and experienced is huge.
Reply | Report Abuse | Link to thisI am a father of a PVS ,Have to tell all that in my openion most of the persistent vegetative state,MCS and LiS have consciousness at some scale but they have no way to show this. My son Jawad Pasha is still without motor function but now we see him responding every voice and happening.The whole system of brain demaged treatment is working on negative theories.I request caregivers to take more care of their patients.These helpless afraid innocent people need more care and your love and care can bring them back but it can take many years,
Reply | Report Abuse | Link to thisI agree what measured is just communication, consciousness has always been there. In facts, I believe consciousness is not in our body(not in any religious way).
Reply | Report Abuse | Link to thisWe are inching to some success and our son Jawad Pasha now seems to be fully conscious. We have got almost a control on his Seizure/Fits but we still know nothing about regaining of motor function. His health is very good but effects of passing almost 5 years on bed are now becomming visible. I am afraid we can loose this all due to very less sources of rehab available to us here at Pakistan. However I feel that we got benifet of having less information about a Persistent Vegetative State term.
Reply | Report Abuse | Link to thisTo the reader
Reply | Report Abuse | Link to thisYou're an idiot to be so arrogant as to actually think you could ever measure anything. Put certainty on something that even allows certainty to be possible? Your brain is too feeble to ever fully comprehend or understand even the how of consciousness to it's greatest lengths.
How about this though, say you understood EVERYTHING intellectually - you would only have the HOW, and not the WHY. You will never have the why, not matter how much you understand anything in the entirety of your existence.
Get over yourself