Journal of Biological Physics

, Volume 35, Issue 4, pp 465–480 | Cite as

On the role of synchrony for neuron–astrocyte interactions and perceptual conscious processing

Original Paper

Abstract

Recent research on brain correlates of cognitive processes revealed the occurrence of global synchronization during conscious processing of sensory stimuli. In spite of technological progress in brain imaging, an explanation of the computational role of synchrony is still a highly controversial issue. In this study, we depart from an analysis of the usage of blood-oxygen-level-dependent functional magnetic resonance imaging for the study of cognitive processing, leading to the identification of evoked local field potentials as the vehicle for sensory patterns that compose conscious episodes. Assuming the “astrocentric hypothesis” formulated by James M. Robertson (astrocytes being the final stage of conscious processing), we propose that the role of global synchrony in perceptual conscious processing is to induce the transfer of information patterns embodied in local field potentials to astrocytic calcium waves, further suggesting that these waves are responsible for the “binding” of spatially distributed patterns into unitary conscious episodes.

Keywords

Astrocytes Perceptual consciousness Local field potentials BOLD signal Functional magnetic resonance Global synchrony Calcium waves 

Notes

Acknowledgements

The authors thank the Brazilian National Research Council (CNPQ) for a grant conceded to APJ; Dr. Bernard Baars, for discussion of an early draft of this paper in his Advanced Seminar (an activity of Consciousness: the Webcourse, supported by the Univ. of Arizona), and two anonymous reviewers for their constructive criticisms and suggestions.

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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.Institute of BiosciencesSão Paulo State University (UNESP)BotucatuBrasil
  2. 2.University of Marília (Unimar)MaríliaBrasil

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