These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Control of hand shaping in response to object shape perturbation.
    Author: Ansuini C, Santello M, Tubaldi F, Massaccesi S, Castiello U.
    Journal: Exp Brain Res; 2007 Jun; 180(1):85-96. PubMed ID: 17256167.
    Abstract:
    This study assessed how hand shaping responds to a perturbation of object shape. In blocked trials (80% of total), subjects were instructed to reach, to grasp and lift a concave or a convex object. In perturbed trials (20% of total), a rotating device allowed for the rapid change from the concave to the convex object or vice versa. In this situation subjects grasped the last presented object. Flexion/extension at the metacarpal-phalangeal and proximal interphalangeal joints of all digits was measured by resistive sensors embedded in a glove. In the blocked condition we found that most joints of the fingers were modulated by the type of the to-be-grasped object during the reach. When object shape was perturbed, reach duration was longer and angular excursion of all fingers differed with respect to blocked trials. For the 'convex --> concave' perturbation, a greater degree of finger extension was found than during the blocked 'concave' trials. In contrast, for the 'concave --> convex' perturbation, fingers were more flexed than for the blocked 'convex' trials. The thumb reacted to the perturbation showing a similar pattern (i.e., over-flexion with respect to the blocked trials) regardless the 'direction' of the perturbation. The present results suggest that applying an object shape perturbation during a reach-to-grasp action determines a reorganization of all digits. This pattern is suggestive of a control strategy, which assigns to opposing digits different roles.
    [Abstract] [Full Text] [Related] [New Search]