A framework for consciousness

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Abstract

Here we summarize our present approach to the problem of consciousness. After an introduction outlining our general strategy, we describe what is meant by the term 'framework' and set it out under ten headings. This framework offers a coherent scheme for explaining the neural correlates of (visual) consciousness in terms of competing cellular assemblies. Most of the ideas we favor have been suggested before, but their combination is original. We also outline some general experimental approaches to the problem and, finally, acknowledge some relevant aspects of the brain that have been left out of the proposed framework.

Figure 1: The snapshot hypothesis proposes that the conscious perception of motion is not represented by the change of firing rate of the relevant neurons, but by the (near) constant firing of certain neurons that represent the motion.
Figure 2: The dendritic arborization of the different types of neurons in the inferior temporal gyrus of the macaque monkey that project to the prefrontal cortex near the principal sulcus (top, shaded gray).

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Acknowledgements

We thank P.S. Churchland, D. Eagleman, G. Kreiman, N. Logothetis, G. Mitchison, T. Poggio, V. Ramachandran, A. Revonsuo and J. Reynolds for thoughtful comments, O. Crick for the drawing and the J.W. Kieckhefer Foundation, the W.M. Keck Foundation Fund for Discovery in Basic Medical Research at Caltech, the National Institutes of Health, the National Institute of Mental Health and the National Science Foundation for financial support.

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Crick, F., Koch, C. A framework for consciousness. Nat Neurosci 6, 119–126 (2003) doi:10.1038/nn0203-119

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