Directed Movement: BBS Call for Commentators

[Stevan Harnad]

    Below is the abstract of a forthcoming target article on:

        SPEED/ACCURACY TRADEOFFS IN TARGET DIRECTED MOVEMENTS
               By Rejean Plamondon & Adel M. Alimi

This article has been accepted for publication in Behavioral and Brain
Sciences (BBS), an international, interdisciplinary journal providing
Open Peer Commentary on important and controversial current research in
the biobehavioral and cognitive sciences.

Commentators must be current BBS Associates or nominated by a current
BBS Associate. To be considered as a commentator for this article, to
suggest other appropriate commentators, or for information about how to
become a BBS Associate, please send email to:

    bbs at soton.ac.uk    or write to:

    Behavioral and Brain Sciences
    Department of Psychology
    University of Southampton
    Highfield, Southampton
    SO17 1BJ UNITED KINGDOM
    http://www.princeton.edu/~harnad/bbs.html
    gopher://gopher.princeton.edu:70/11/.libraries/.pujournals
    ftp://ftp.princeton.edu/pub/harnad/BBS
    
To help us put together a balanced list of commentators, please give
some indication of the aspects of the topic on which you would bring
your areas of expertise to bear if you were selected as a commentator.
An electronic draft of the full text is available for inspection by
anonymous ftp (or gopher or world-wide-web) according to the
instructions that follow after the abstract.
____________________________________________________________________


        SPEED/ACCURACY TRADEOFFS IN TARGET DIRECTED MOVEMENTS
 
                    Rejean Plamondon & Adel M. Alimi
                    Ecole Polytechnique de Montreal
                    Laboratoire Scribens
                    Departement de genie Electrique
                    et de genie informatique
                    C.P. 6079, Succ. "Centre-Ville"
                    Montreal PQ      H3C 3A7
                    ha03 at music.mus.polymtl.ca
 
    KEYWORDS: Speed/accuracy tradeoffs, Fitts' law, central limit
    theorem, velocity profile, delta-lognormal law, quadratic law,
    power law.
 
    ABSTRACT: This paper presents a critical survey of the scientific
    literature dealing with the speed/accuracy tradeoffs of rapid-aimed
    movements.  It highlights the numerous mathematical and theoretical
    interpretations that have been proposed over recent decades from
    the different studies that have been conducted on this topic.
    Although the variety of points of view reflects the richness of the
    field as well as the high degree of interest that such basic
    phenomena represent in the understanding of human movements, it
    questions the validity of many models with respect to their
    capacity to explain all the basic observations consistently
    reported in the field.  In this perspective, this paper summarizes
    the kinematic theory of rapid human movements, proposed recently by
    the first author, and analyzes its predictions in the context of
    speed/accuracy tradeoffs. Numerous data available from the
    scientific literature are reanalyzed and reinterpreted in the
    context of this new theory.  It is shown that the various aspects
    of the speed/accuracy tradeoffs can be taken into account by
    considering the asymptotic behavior of a large number of coupled
    linear systems, from which a delta-lognormal law can be derived, to
    describe the velocity profile of an end-effector driven by a
    neuromuscular synergy.  This law not only describes velocity
    profiles almost perfectly, but it also predicts the kinematic
    properties of simple rapid movements and provides a consistent
    framework for the analysis of different types of rapid movements
    using a quadratic (or power) law that emerges from the model.

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To help you decide whether you would be an appropriate commentator for
this article, an electronic draft is retrievable by anonymous ftp from
ftp.princeton.edu according to the instructions below (the filename is
bbs.glenberg). Please do not prepare a commentary on this draft.
Just let us know, after having inspected it, what relevant expertise
you feel you would bring to bear on what aspect of the article.
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    ftp://ftp.princeton.edu/pub/harnad/BBS/bbs.glenberg
    ftp://cogsci.soton.ac.uk/pub/harnad/BBS/bbs.glenberg

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