Tuesday, September 4, 2012

Moment of consciousness...when?

"When Do We Become Truly Conscious?"



Daniel Bor

September 4th, 2012


It is easy to view consciousness as a kind of magic. In religion it is represented by the mysterious soul, and in science the concept of consciousness at first appears quite alien. But many fields, such as the study of what distinguishes life from nonlife, had their earlier magical states eroded by careful scientific study. Consciousness is in the midst of a similar revolution.

The investigation of our own awareness is a blossoming scientific field, where experiments are illuminating exciting details about this most intimate of scientific subjects. In my book The Ravenous Brain, I describe the latest consciousness science and how we are closing in on establishing a consciousness meter—a way to measure levels of awareness in any being that may be able to experience the world. Consciousness is in many ways the most important question remaining for science.

But the nature of consciousness is not just a vital question for science; it’s also the source of some of society’s thorniest, most fundamental ethical dilemmas.

On a personal level, consciousness is where the meaning to life resides. All the moments that matter to us, from falling in love to seeing our child’s first smile, to that perfect holiday surrounded by snow-capped mountains, are obviously conscious events. If none of these events were conscious, if we weren’t conscious to experience them, we’d hardly consider ourselves alive—at least not in any way that matters.


Although some philosophers and scientists suspect that consciousness is a pointless side effect of cognitive processes, I believe the opposite: that our consciousness might indeed be responsible for our greatest intellectual achievements in both the arts and sciences. Whether our creativity and insight originates in our unconscious mind or not (I believe that the role of the unconscious has been overestimated), at the very least, our consciousness is the conduit to inspect these gems of inspiration and the driving force for turning them into reality.

It is not surprising, therefore, that questions about consciousness lie at the heart of many of our most fundamental ethical debates, one of which is abortion and the right to life. This is an appropriate point for me to play my proud father card and slip in a couple of pictures of my daughter, Lalana. The ultrasound was taken halfway through pregnancy, at 20 weeks. Soon after this scan, we could clearly feel her kicking.

The second image is a recent photo of her. As a 2-year-old, Lalana runs around everywhere and has a vocabulary of a few hundred words. She can convey events to us that happened days or weeks before, usually because she is still so excited about them. She can also store wishes for the future. For instance, we might tell her offhand that when we get home, we’ll play with making bubbles. Hours later, as soon as she enters the house, she’ll run straight to the shelf with the bubble bottle and scream, “Bubbu! Bubbu!” She has a strong set of loves and hates, and her emotionally sensitive, passionate, cheeky, disturbingly stubborn personality is already pronounced.

Having prided myself on my objectivity throughout my adult life, I’ve embarrassingly found that my daughter is the main exception to this aim: I’ve not only been taken aback by how fiercely I love her but also by how proud I am of her and how quickly I distort the truth to make her seem exceptional in every way. But when I can step back from these views, I ask myself: At what point did she become conscious? Obviously she is conscious now, as she can tell me her inner thoughts via language. But when did she start experiencing her environment? On a personal, intuitive level, I had little doubt that her first intense bursts of laughter at my silly antics, when she was a few months old, reflected a substantive consciousness. But was she conscious well before this? Was she aware when she was still in the womb, kicking away? Or could she only experience things when she first opened her eyes to the outside world on the day of her birth?

Finding answers to these questions isn’t merely a matter of curiosity. In the United States, people have been murdered for carrying out abortions. In many other countries, abortion is illegal even if the woman has been raped, and some prominent U.S. politicians, including Republican vice-presidential nominee Paul Ryan, support similarly harsh laws. Although such positions are usually determined by religion, a related mindset is that fetuses are already conscious and even capable of feeling pain. Indeed, this has recently been the basis states have used to further restrict a woman’s rights on this issue, with Arizona the latest state to join this group by disallowing abortions after 20 weeks.

But what does science have to say on this matter? The evidence is clear that a fetus can respond to sights, sounds, and smells, and it can even react to these by producing facial expressions. The evidence is equally clear, however, that these responses are generated by the most primitive parts of the brain, which are unconnected to consciousness, and therefore these actions don’t in any way imply that the fetus is aware. Furthermore, the fetus is deliberately sedated by a series of chemicals produced by the placenta, so even if it had the capacity for consciousness, there is almost no chance that it could ever be conscious in the womb. Consequently, it can’t consciously feel pain.

But what if the fetus is removed from the womb and its sleep-inducing chemicals? Will the fetus suddenly be conscious in the outside world? In adult humans, for normal consciousness to occur, it is now generally agreed that two sets of regions need to be intact, functional, and able to communicate effectively with one another: the thalamus, a kind of relay station in the middle of the brain that connects many regions with many others; and the prefrontal parietal network, our most high-level, general purpose section of cortex. If either the thalamus or prefrontal parietal network is substantially damaged, the patient is likely to enter into a vegetative state, with virtually no sign of consciousness.

When do these brain regions form in the growing fetus? Only after about 29 weeks are the connections between these areas properly laid out, and it takes another month or so before the thalamus and the rest of the cortex are effectively communicating, as revealed by brain waves. So it’s highly unlikely that consciousness, at least in any form that we’d recognize as human awareness, arises before about 33 weeks into pregnancy. There are therefore no scientific reasons for restricting abortion on the grounds that the fetus will experience pain, at least until very late in pregnancy. This evidence has heavily influenced my views here, and consequently I am very much pro-choice.

Another ethical issue that hinges on questions of consciousness is that of animal rights. Every person on the planet, on average, consumes twice his or her weight in animal-derived food each year. Food production, as well as animal experimentation, could be causing the suffering of many millions of animals yearly.

If no animals except humans have consciousness, there’s no problem, as suffering requires consciousness. But if even those animals classically assumed to have very limited mental faculties, such as poultry and fish, have a substantive awareness and significant capacity for suffering, then are we justified in inflicting all this pain and discomfort on them?

If science could come up with some means of testing for the presence of consciousness in other animals and perhaps also a way of gauging the extent of consciousness when it’s found, this would have a huge impact on all ethical spheres of the animal rights debate.

On the surface, because animals can’t use language to tell us they are conscious, this seems an intractable problem. But a surprising amount of evidence has emerged that addresses the question of animal consciousness. For a start, we can ask which other species have brain regions similar to those we know are critical for human consciousness, namely the thalamus and prefrontal parietal network. Most mammals share these structures with us in some form, suggesting strongly that they too have some significant levels of consciousness. But this is a problematic approach, ignoring the possibility that very distant species independently evolved the capacity for consciousness. For instance, crows can use a series of tools to hook a juicy grub, and octopuses can open a screw-on lid to a jar to retrieve a tasty crab. Although these animals have no cortex, they appear to demonstrate a mental life that many would classify as conscious.











Daniel Bor

ISBN-10: 046502047X
ISBN-13: 978-0465020478

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