Paradox and cross purposes in recent work on consciousness

doi:10.1016/S0010-0277(00)00129-3

Cognition

Volume 79, Issues 1–2, April 2001, Pages 197-219

https://doi.org/10.1016/S0010-0277(00)00129-3 Get rights and content

Abstract

Functionalists about consciousness identify consciousness with a role; physicalists identify consciousness with an implementer of that role. The global workspace theory of consciousness fits the functionalist perspective, but the physicalist sees consciousness as a biological phenomenon that implements global accessibility.

Introduction

Dehaene and Naccache, Dennett and Jack and Shallice (this volume) “see convergence coming from many different quarters on a version of the neuronal global workspace model” (Dennett). On the contrary, even within this volume, there are commitments to very different perspectives on consciousness. And these differing perspectives are based on tacit differences in philosophical starting places that should be made explicit. Indeed, it is not clear that different uses of ‘consciousness’ and ‘awareness’ in this volume can be taken to refer to the same phenomenon. More specifically, I think there are three different concepts of consciousness in play in this issue. The global workspace model makes much more sense on one of these than on the others.

Part of the point of this comment is that ‘consciousness’ and ‘awareness’ are ambiguous terms, and I often follow the usage of authors being discussed in using these terms without specifying a sense.

Section snippets

The paradox of recent findings about consciousness

The most exciting and puzzling results described in this issue appear in a linked set of experiments reported by Kanwisher, Driver and Vuilleumier and Dehaene and Naccache (this volume). Kanwisher notes that “…neural correlates of perceptual experience, an exotic and elusive quarry just a few years ago, have suddenly become almost commonplace findings”. And she backs this up with impressive correlations between neural activation on the one hand and indications of perceptual experiences of

What are experiments ‘about consciousness’ really about?

Merikle, Smilek and Eastwood (this volume) describe the Debner and Jacoby (1994) ‘exclusion’ paradigm, in which subjects follow instructions not to complete a word stem with the end of a masked word just presented to them only if the word is presented consciously (lightly masked). If the word is presented unconsciously (heavily masked), the subjects are more likely than baseline to disobey the instructions, completing the stem with the very word that was presented.

But what is the

Is it impossible in principle to empirically distinguish phenomenality from reflexivity?

Some objectors think that the distinction between phenomenality and reflexivity has no real empirical significance. Here is a version of that view: ‘In order to ascertain empirically whether a phenomenal state is present or absent or what its content is, we require the subject's testimony. But when a subject says that he did or didn't see something, or that his state did or didn't have a certain content, he is exhibiting presence or absence of the relevant reflexive consciousness too. So how

Conclusion

The papers in this volume deploy three different concepts of consciousness.

1.
Phenomenality: experience. This is the concept of consciousness that is most directly the subject of the hypothesis discussed by Driver and Vuilleumier and Kanwisher that visual consciousness is ventral stream activation plus X.
2.
Access consciousness: global accessibility. This is the concept of consciousness most directly related to Dehaene and Naccache's account of consciousness as being broadcast in a global neuronal

Acknowledgements

I am grateful to Susan Carey, Nancy Kanwisher, Georges Rey and Jesse Prinz for comments on an earlier version, and I am especially grateful to Stan Dehaene and Tony Jack for many rounds of debate on key issues on which we disagree. The paper has been much improved as a result of these controversies.

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The dual model agrees with the unitary model in that conscious phenomenal states possess the experiential what-it’s-like-ness and that unconscious mental states lack it. However, it allows that unconscious mental states possess phenomenal character (or phenomenality, as Ned Block calls it; see Block, 2001). On this view, the experiential what-it’s-like-ness is simply a result of the combination of phenomenal character and consciousness.
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Paradox and cross purposes in recent work on consciousness

Abstract

Introduction

Section snippets

The paradox of recent findings about consciousness

What are experiments ‘about consciousness’ really about?

Is it impossible in principle to empirically distinguish phenomenality from reflexivity?

Conclusion

Acknowledgements

Consciousness and Cognition

Consciousness and Cognition

Trends in Cognitive Science

The control of short-term memory

Scientific American

A cognitive theory of consciousness

How can we find the neural correlate of consciousness?

Trends in Neuroscience

Biology vs. computation in the study of consciousness

Behavioral and Brain Sciences

Two kinds of consciousness

Levels of representation, coordinate frames, and unilateral neglect

Cognitive Neuropsychology