Please use this identifier to cite or link to this item:
Type: Artigo de periódico
Title: Kinematic Description Of Variability Of Fast Movements: Analytical And Experimental Approaches
Author: Gutman S.R.
Latash M.L.
Almeida G.L.
Gottlieb G.L.
Abstract: Analysis of variability of fast aimed movements predicts the properties of trajectory variance. The analysis is based on a kinematic model with nonlinear changes in "internal time". The purpose of the work was to identify different sources of variability and their influence on the trajectory variance. An analytical expression for the speed-accuracy trade-off is introduced. Experiments were performed with subjects making single-joint elbow flexion movements over different distances as fast as possible with their eyes closed to memorized targets. Standard deviation of movement trajectory increased during the first part of the movement and subsequently decreased. The variance peaked after the time of peak velocity, close to the time of peak deceleration. A dependence of the trajectory variance on movement distance (speed-accuracy trade-off) was seen during the movement (at times of peak velocity and peak deceleration) but not after the movement termination. We conclude that the previously reported drop in the variability of movement trajectory during the deceleration phase does not necessarily mean a compensation by the control system but may result from purely kinematic properties of the movement. The importance of the time of measurement for analysis of the speed-accuracy trade-offs is emphasized. © 1993 Springer-Verlag.
Editor: Springer-Verlag
Rights: fechado
Identifier DOI: 10.1007/BF00199448
Date Issue: 1993
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File SizeFormat 
2-s2.0-0027758989.pdf779.1 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.