High-resolution imaging of skin deformation shows that afferents from human fingertips signal slip onset
Abstract
Human tactile afferents provide essential feedback for grasp stability during dexterous object manipulation. Interacting forces between an object and the fingers induce slip events that are thought to provide information about grasp stability. To gain insight into this phenomenon, we made a transparent surface slip against a fixed fingerpad while monitoring skin deformation at the contact. Using microneurography, we simultaneously recorded the activity of single tactile afferents innervating the fingertips. This unique combination allowed us to describe how afferents respond to slip events and to relate their responses to surface deformations taking place inside their receptive fields. We found that all afferents were sensitive to slip events, but FA-I afferents in particular faithfully encoded compressive strain rates resulting from those slips. Given the high density of FA-I afferents in fingerpads, they are well suited to detect incipient slips and to provide essential information for the control of grip force during manipulation.
Data availability
All the data used to create the figures in the manuscript are available for download following this permanent dropbox link:https://www.dropbox.com/sh/vhozyj03o401sud/AADGmJeXj4zAjL8RsSb5OInja?dl=0
Article and author information
Author details
Funding
European Space Agency (/)
- Jean-Louis Thonnard
- Philippe Lefèvre
PRODEX (/)
- Jean-Louis Thonnard
- Philippe Lefèvre
Swedish Research Council (VR 2016-01635)
- Benoni Edin
Fonds De La Recherche Scientifique - FNRS (/)
- Benoit P Delhaye
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Cornelius Schwarz
Ethics
Human subjects: Each subject provided written informed consent to the procedures, and the study was approved by the local ethics committee at the host institution (Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium).
Version history
- Received: November 6, 2020
- Accepted: April 13, 2021
- Accepted Manuscript published: April 22, 2021 (version 1)
- Version of Record published: June 1, 2021 (version 2)
- Version of Record updated: June 7, 2021 (version 3)
Copyright
© 2021, Delhaye et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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