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Edge-orientation processing in first-order tactile neurons

Nature Neuroscience volume 17, pages 14041409 (2014) | Download Citation

Abstract

A fundamental feature of first-order neurons in the tactile system is that their distal axon branches in the skin and forms many transduction sites, yielding complex receptive fields with many highly sensitive zones. We found that this arrangement constitutes a peripheral neural mechanism that allows individual neurons to signal geometric features of touched objects. Specifically, we observed that two types of first-order tactile neurons that densely innervate the glabrous skin of the human fingertips signaled edge orientation via both the intensity and the temporal structure of their responses. Moreover, we found that the spatial layout of a neuron's highly sensitive zones predicted its sensitivity to particular edge orientations. We submit that peripheral neurons in the touch-processing pathway, as with peripheral neurons in the visual-processing pathway, perform feature extraction computations that are typically attributed to neurons in the cerebral cortex.

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Change history

  • Corrected online 15 September 2014

    In the version of this supplementary file originally posted online, the raster image in Supplementary Figure 2a was left/right mirror-reversed. The error has been corrected in this file as of 15 September 2014.

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Acknowledgements

We thank B. Edin and D. Wolpert for their helpful comments on previous versions of this manuscript. We thank A. Bäckström, C. Hjältén, E. Jarocka, P. Jenmalm, P. Utsi and G. Westling for their technical and logistical support. This work was funded by the Swedish Research Council Projects 08667 and 22209, as well as by the Strategic Research Program in Neuroscience at the Karolinska Institute. J.A.P. received a long-term fellowship from the Human Frontier Science Program.

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  1. Physiology Section, Department of Integrative Medical Biology, Umeå University, Umeå, Sweden.

    • J Andrew Pruszynski
    •  & Roland S Johansson

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Both authors contributed extensively to the work presented in this paper.

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The authors declare no competing financial interests.

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Correspondence to J Andrew Pruszynski.

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https://doi.org/10.1038/nn.3804