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Encoding of Shape in the Responses of Cutaneous Mechanoreceptors

  • Mandayam A. Srinivasan
  • Robert H. LaMotte
Chapter
Part of the Wenner-Gren Center International Symposium Series book series

Abstract

Tactile detection of surface features of objects is essential for successful exploration and manipulation of our environment. Primates predominantly use fingerpads for exploring small features, owing to the high density of cutaneous mechanoreceptors (Johansson and Vallbo, 1979; Darian-Smith and Renins, 1980) which results in high spatial resolution, as well as due to the dexterity and fine motion control achieved with multiple degrees of freedom to move the fingertip. For humans, the normal contact forces used and the compliance of the fingertip result in contact regions whose overall diameter measures about a centimeter. At any time during contact, the information conveyed by cutaneous mechanoreceptors pertain only to the features within the contact region, thereby limiting the largest lengthscale of the surface features represented in cutaneous information to be of the order of centimeters. The smallest lengthscale is governed by the response thresholds of mechanoreceptors, which can be as low as fractions of a micron (LaMotte and Srinivasan, 1990). In this article we are concerned with millimeter to centimeter sized surface features of rigid objects, the shape of which can be detected from purely cutaneous information.

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Copyright information

© Macmillan Publishers Limited 1991

Authors and Affiliations

  • Mandayam A. Srinivasan
  • Robert H. LaMotte

There are no affiliations available

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