Stretching the skin immediately enhances perceived stiffness and gradually enhances the predictive control of grip force
Abstract
When manipulating objects, we use kinesthetic and tactile information to form an internal representation of their mechanical properties for cognitive perception and for preventing their slippage using predictive control of grip force. A major challenge in understanding the dissociable contributions of tactile and kinesthetic information to perception and action is the natural coupling between them. Unlike previous studies that addressed this question by focusing on impaired sensory processing in patients or via local anesthesia, we used a behavioral study with a programmable mechatronic device that stretches the skin of the fingertips to address this issue in the intact sensorimotor system. We found that artificial skin-stretch increases the predictive grip force modulation in anticipation of the load force. Moreover, the stretch causes an immediate illusion of touching a harder object that does not depend on the gradual development of the predictive modulation of grip force.
Data availability
Our analysis code and data is available via GitHub, at https://github.com/bgu-SkinStretch/Farajian_et_al2020
Article and author information
Author details
Funding
Israel Science Foundation (823/15)
- Ilana Nisky
National Science Foundation (1632259)
- Ferdinando A Mussa-Ivaldi
United States-Israel Binational Science Foundation (2016850)
- Ferdinando A Mussa-Ivaldi
- Ilana Nisky
ABC Robotics Initiative at Ben-Gurion University of the Negev
- Ilana Nisky
Ministry of Science and Technology (Israel-Italy virtual lab on
- Ilana Nisky
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Eilon Vaadia, The Hebrew University of Jerusalem, Israel
Ethics
Human subjects: All the participants of the experiments signed a written informed consent form. Prior to signing the form, they read the information in a printed form, and heard an explanation by the experimenter. The procedures and the consent form were approved by the Human Subjects Research Committee of Ben Gurion University of the Negev, Be'er-Sheva, Israel, approval number 1283-1, dated from July 6th, 2015.
Version history
- Received: October 11, 2019
- Accepted: April 2, 2020
- Accepted Manuscript published: April 15, 2020 (version 1)
- Version of Record published: April 22, 2020 (version 2)
Copyright
© 2020, Farajian 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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