Document Detail


Three-dimensional arm movements at constant equi-affine speed.
MedLine Citation:
PMID:  18678364     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
It has long been acknowledged that planar hand drawing movements conform to a relationship between movement speed and shape, such that movement speed is inversely proportional to the curvature to the power of one-third. Previous literature has detailed potential explanations for the power law's existence as well as systematic deviations from it. However, the case of speed-shape relations for three-dimensional (3D) drawing movements has remained largely unstudied. In this paper we first derive a generalization of the planar power law to 3D movements, which is based on the principle that this power law implies motion at constant equi-affine speed. This generalization results in a 3D power law where speed is inversely related to the one-third power of the curvature multiplied by the one-sixth power of the torsion. Next, we present data from human 3D scribbling movements, and compare the obtained speed-shape relation to that predicted by the 3D power law. Our results indicate that the introduction of the torsion term into the 3D power law accounts for significantly more of the variance in speed-shape relations of the movement data and that the obtained exponents are very close to the predicted values.
Authors:
Frank E Pollick; Uri Maoz; Amir A Handzel; Peter J Giblin; Guillermo Sapiro; Tamar Flash
Related Documents :
15178534 - Target-size influences on reaction time with movement time controlled.
19897414 - Quantifying movement demands of afl football using gps tracking.
8359264 - Principles for learning single-joint movements. i. enhanced performance by practice.
9430754 - An examination of the degrees of freedom of human jaw motion in speech and mastication.
11124454 - Auditory nerve responses to monophasic and biphasic electric stimuli.
17453844 - Effects of transient and continuous wheel running activity on the upper and lower limit...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2008-06-28
Journal Detail:
Title:  Cortex; a journal devoted to the study of the nervous system and behavior     Volume:  45     ISSN:  0010-9452     ISO Abbreviation:  Cortex     Publication Date:  2009 Mar 
Date Detail:
Created Date:  2009-02-02     Completed Date:  2009-06-24     Revised Date:  2009-11-11    
Medline Journal Info:
Nlm Unique ID:  0100725     Medline TA:  Cortex     Country:  Italy    
Other Details:
Languages:  eng     Pagination:  325-39     Citation Subset:  IM    
Affiliation:
Department of Psychology, University of Glasgow, United Kingdom. frank@psy.gla.ac.uk
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Biomechanics / physiology
Female
Generalization (Psychology) / physiology
Humans
Imitative Behavior / physiology*
Male
Mathematics
Middle Aged
Motion Perception / physiology*
Movement / physiology*
Psychomotor Performance / physiology*
Space Perception / physiology*
Young Adult

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  In vivo osteopontin-induced macrophage accumulation is dependent on CD44 expression.
Next Document:  Antagonist/letrozole protocol in poor ovarian responders for intracytoplasmic sperm injection: a com...