Fast and accurate edge orientation processing during object manipulation
Abstract
Quickly and accurately extracting information about a touched object's orientation is a critical aspect of dexterous object manipulation. However, the speed and acuity of tactile edge orientation processing with respect to the fingertips as reported in previous perceptual studies appear inadequate in these respects. Here we directly establish the tactile system's capacity to process edge-orientation information during dexterous manipulation. Participants extracted tactile information about edge orientation very quickly, using it within 200 ms of first touching the object. Participants were also strikingly accurate. With edges spanning the entire fingertip, edge-orientation resolution was better than 3° in our object manipulation task, which is several times better than reported in previous perceptual studies. Performance remained impressive even with edges as short as 2 mm, consistent with our ability to precisely manipulate very small objects. Taken together, our results radically redefine the spatial processing capacity of the tactile system.
Article and author information
Author details
Funding
Canadian Institutes of Health Research (Foundation Grant 3531979)
- J Andrew Pruszynski
Vetenskapsrådet (Project 22209)
- J Andrew Pruszynski
Canadian Institutes of Health Research (OOGP 82837)
- J Randall Flanagan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: Twenty healthy people volunteered for these experiments. All participants provided written informed consent in accordance with the Declaration of Helsinki. The ethics committee at Umea University approved the study.
Copyright
© 2018, Pruszynski 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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