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Article Excerpt
Consciousness: A user's guide
By Adam Zeman
Yale, CT: Yale University Press. 2003. Hbk [pounds sterling]18.95, ISBN 0-300-09280-62004. Pbk [pounds sterling]10.99, ISBN 0-300-10497-9
Mirror neurons and the evolution of brain and language
Edited by Maxim I. Stamenov and Vittorio Gallese
Amsterdam: John Benjamins. 2002. Hbk [euro]110.00, ISBN 90-272-5166-5. Pbk [euro]72.00, ISBN 90-272-5162-2
Consciousness: Creeping up on the hard problem
By Jeffrey Gray
Oxford: Oxford University Press. 2004. Hbk [pounds sterling]29.95, ISBN 0-19-852090-5. Pbk ISBN 978-019-852090-0
Consciousness: An introduction
By Susan Blackmore
London: Hodder and Stoughton. 2003. Pbk [pounds sterling]16.99, ISBN 0-3408-09094
In this review essay, I discuss four recent books ranging from philosophical to neuropsychological approaches to consciousness. The books are just a small selection from a large number of recent texts that have not only been insisting that we should take consciousness as a serious subject for scientific study, but which also have identified themselves with the new field of 'consciousness studies'. The books in review represent not just new publications of this line of study. They also represent a typical variety of approaches, mirroring different interpretations of 'the problem of consciousness'.
Consciousness studies has developed over the last 20 or so years as an autonomous, yet interdisciplinary, field of research and theory, embracing philosophy, psychology and neuroscience. Since consciousness studies have yet to become part of the curriculum of mainstream psychology, I first provide an outline of the field of consciousness studies, and its central themes and problems. Furthermore, as the books under review themselves demonstrate, there is no consensus about what even constitutes the problem of consciousness, although each takes consciousness as its central topic. Each of the books attempts, in its own way, to provide an overview of this new field of research, and so, having reviewed each according to its own merits, I make comparisons among them. Finally, since the books offer their own projections about the future of consciousness studies, I close this review with my own reflections concerning the prospects for this new science and its possible relations with psychology.
The history of consciousness studies
Unravelling the history of the new interest in consciousness is surprisingly difficult, even though it has been around only for a few decades. One possible reason for this is the fact that the field of consciousness studies is defined interdisciplinarily. In philosophy, it is commonly held that the interest in consciousness, at least formulated as a 'mind-body problem', came about with Rene Descartes. Descartes famously claimed that subjective conscious states are separate from the world and that they causally interact with the world through their physical seat, the brain. While this framework has long been abandoned, philosophical debates about consciousness have nevertheless largely been focused on the metaphysics of consciousness. How can something essentially subjective--the phenomenal experiences of a given person or animal--exist in a material world? The debate has primarily involved the materialists, who claim that phenomenal consciousness, in spite of our everyday intuition, actually refers to physical phenomena (brain processes), on the one side, and the dualists on the other, who insist that consciousness is neither identical nor reducible to something material. In experimental psychology, however, the story is quite different. In the late nineteenth century, the German, American and French introspectionists set out to study consciousness experimentally by varying physical stimuli and collecting reports of the corresponding subjective variations. As a result of many methodological conflicts in which different laboratories kept failing to reproduce each others' results, introspectionism declined and the more experimentally promising paradigm of behaviourism took over as a leading trend in psychology. As behaviourism in its most radical versions famously denied the existence (or, as in Skinner's case, the explanatory relevance) of 'internal' or 'mental states', so did theorizing about--or even the very mention of--consciousness disappear from mainstream psychology.
Since the 1980s, and some 30 years after the 'cognitive revolution', there has been a growing revival of interest in consciousness among psychologists, philosophers and neuroscientists. As the history of the revival of interest in consciousness is different in the various disciplines contributing to its study, so the reasons for this revival are also diverse. Several recent philosophical articles and books have discussed paradigms within experimental psychology, especially the currently dominant paradigm of cognitive psychology. Their important criticism of cognitive science has been that it has not succeeded in moving on from behaviourism in its fundamental methodology and assumptions (Leahey, 1987). First and foremost, the argument has been that cognitivist theories are unable to embrace consciousness. Basically, the kinds of models that cognitive theories adopt--algorithmical modelling and 'boxes with arrows between them'--do not in any relevant way describe what our experiences are like to ourselves. Indeed, this kind of 'boxology' could never do so, as a matter of principle. Therefore, we need a different experimental framework to deal with conscious rather than objectified subjects. If not, it is argued, we will accept a psychological framework that is at best agnostic when it comes to the one feature that is most prominent and clearly present in our everyday lives--that is, consciousness. Within experimental psychology itself, an increasing number of scientists have found it useful to apply the concept of consciousness at both a descriptive and explanatory level to phenomena known to psychology. For well-known phenomena such as subliminal perception, it has proved reasonable to speak of being 'above' or 'below' a perceptual threshold as a matter of being either in a conscious or unconscious perceptual state. This, also, has a 'phenomenological validity'--that is, the concepts actually address what it is like for a subject to experience being above or below threshold. Other examples of findings that were easily described with an appeal to consciousness have been neuropsychological syndromes such as blindsight and agnosia, where patients prove to be informed about worldly happenings even though they are unconscious of them. The ambition quickly arose, based upon such contrasts between consciousness and unconciousness, to use consciousness as an experimental variable in the search for neural correlates of consciousness.
By the beginning of the 1990s, enthusiasm was growing for the development of a new and separate, interdisciplinary 'science of consciousness'. This development was in part, at least, inspired by a paper by Francis Crick and Christof Koch entitled "Toward a neurobiological theory of consciousness' (1990) and kept alive by the annual conference series Toward a Science of Consciousness, organized by the Center for Consciousness Studies at the University of Arizona. Even though we here also find attempts to discuss ontological issues about consciousness, the genuinely new development is the very idea that there could be a distinctive science of consciousness. That is, the suggestion is that, with some degree of methodological innovation, cognitive science or neuroscience could directly target consciousness as an object of empirical study, and not simply, as had previously been the case, try to make claims about the nature of consciousness based upon experiments that had actually been developed to address quite different issues. Consciousness studies may thus be said to have arisen as a theoretically guided change of focus and explanation in empirical research. At least, the attempt to arrive at an empirical science of consciousness is thought by many to be the end goal of the theoretical work.
Regardless of the aspirations of those working with consciousness studies for a new science, some, like Bernard Baars (1988), have argued that we do already have a science of consciousness, namely, cognitive psychology. This is, however, a rather extreme view. There is wide agreement that there is a methodological version of the mind-body problem, and that this problem arises precisely because the current methods of cognitive science fail to address consciousness. In order to counter the rather complacent view expressed by Baars, it is necessary to distinguish between two research paradigms within the overall discipline called cognitive science. I shall call them 'classical cognitive science' and 'cognitive neuroscience'. In some respects, these two approaches are similar: classical cognitive scientists and cognitive neuroscientists would certainly share some interest in the same experimental research (although the cognitive neuroscientists might be less interested in experiments having nothing to do directly with the brain), and they would be in perfect agreement about how to analyse...
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