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What are the mechanisms for analogue and digital signalling in the brain?

Nature Reviews Neuroscience volume 14, pages 63–69 (2013)Cite this article

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Abstract

Synaptic transmission in the brain generally depends on action potentials. However, recent studies indicate that subthreshold variation in the presynaptic membrane potential also determines spike-evoked transmission. The informational content of each presynaptic action potential is therefore greater than initially expected. The contribution of this synaptic property, which is a fast (from 0.01 to 10 s) and state-dependent modulation of functional coupling, has been largely underestimated and could have important consequences for our understanding of information processing in neural networks. We discuss here how the membrane voltage of the presynaptic terminal might modulate neurotransmitter release by mechanisms that do not involve a change in presynaptic Ca2+ influx.

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Figure 1: Digital, analogue and hybrid (analogue–digital) modes of synaptic transmission
Figure 2: Generic mechanisms for analogue–digital facilitation.

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Acknowledgements

The authors are supported by INSERM, Aix-Marseille Université, Centre National de la Recherche Scientifique, Agence Nationale de la Recherche (ANR 11 BSV4 016 01), Fondation pour le Recherche Medicale and the French Ministry of Research. We thank H. Alle, O. El Far, J.-M. Goaillard, V. Marra, M. Seagar and the reviewers for helpful discussion and comments on the manuscript.

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  1. Dominique Debanne, Andrzej Bialowas and Sylvain Rama are at INSERM, UMR_S 1072, and Aix-Marseille Université, UNIS, 13015, Marseille, France.,

    Dominique Debanne, Andrzej Bialowas & Sylvain Rama

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Correspondence to Dominique Debanne.

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Debanne, D., Bialowas, A. & Rama, S. What are the mechanisms for analogue and digital signalling in the brain?. Nat Rev Neurosci 14, 63–69 (2013). https://doi.org/10.1038/nrn3361

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