Age-related changes in multifinger synergies in accurate moment of force production tasks

Halla Olafsdottir, Wei Zhang, Vladimir M. Zatsiorsky, Mark L. Latash

Research output: Contribution to journalArticle

68 Citations (Scopus)

Abstract

The purpose of this investigation was to document and quantify age-related differences in the coordination of fingers during a task that required production of an accurate time profile of the total moment of force by the four fingers of a hand. We hypothesized that elderly subjects would show a decreased ability to stabilize a time profile of the total moment of force, leading to larger indexes of moment variability compared with young subjects. The subjects followed a trapezoidal template on a computer screen by producing a time profile of the total moment of force while pressing down on force sensors with the four fingers of the right (dominant) hand. To quantify synergies, we used the framework of the uncontrolled manifold hypothesis. The elderly subjects produced larger total force, larger variance of both total force and total moment of force, and larger involvement of fingers that produced moment of force against the required moment direction (antagonist moment). This was particularly prominent during supination efforts. Young subjects showed covariation of commands to fingers across trials that stabilized the moment of total force (moment-stabilizing synergy), while elderly subjects failed to do so. Both subject groups showed similar indexes of covariation of commands to the fingers that stabilized the time profile of the total force. The lack of moment-stabilizing synergies may be causally related to the documented impairment of hand function with age.

Original languageEnglish (US)
Pages (from-to)1490-1501
Number of pages12
JournalJournal of applied physiology
Volume102
Issue number4
DOIs
StatePublished - Apr 1 2007

Fingerprint

Advisory Committees
Fingers
Hand
Supination

All Science Journal Classification (ASJC) codes

  • Physiology
  • Physiology (medical)

Cite this

Olafsdottir, Halla ; Zhang, Wei ; Zatsiorsky, Vladimir M. ; Latash, Mark L. / Age-related changes in multifinger synergies in accurate moment of force production tasks. In: Journal of applied physiology. 2007 ; Vol. 102, No. 4. pp. 1490-1501.
@article{968d5e79168b443cb826bb00b4f0fa2a,
title = "Age-related changes in multifinger synergies in accurate moment of force production tasks",
abstract = "The purpose of this investigation was to document and quantify age-related differences in the coordination of fingers during a task that required production of an accurate time profile of the total moment of force by the four fingers of a hand. We hypothesized that elderly subjects would show a decreased ability to stabilize a time profile of the total moment of force, leading to larger indexes of moment variability compared with young subjects. The subjects followed a trapezoidal template on a computer screen by producing a time profile of the total moment of force while pressing down on force sensors with the four fingers of the right (dominant) hand. To quantify synergies, we used the framework of the uncontrolled manifold hypothesis. The elderly subjects produced larger total force, larger variance of both total force and total moment of force, and larger involvement of fingers that produced moment of force against the required moment direction (antagonist moment). This was particularly prominent during supination efforts. Young subjects showed covariation of commands to fingers across trials that stabilized the moment of total force (moment-stabilizing synergy), while elderly subjects failed to do so. Both subject groups showed similar indexes of covariation of commands to the fingers that stabilized the time profile of the total force. The lack of moment-stabilizing synergies may be causally related to the documented impairment of hand function with age.",
author = "Halla Olafsdottir and Wei Zhang and Zatsiorsky, {Vladimir M.} and Latash, {Mark L.}",
year = "2007",
month = "4",
day = "1",
doi = "10.1152/japplphysiol.00966.2006",
language = "English (US)",
volume = "102",
pages = "1490--1501",
journal = "Journal of Applied Physiology",
issn = "8750-7587",
publisher = "American Physiological Society",
number = "4",

}

Age-related changes in multifinger synergies in accurate moment of force production tasks. / Olafsdottir, Halla; Zhang, Wei; Zatsiorsky, Vladimir M.; Latash, Mark L.

In: Journal of applied physiology, Vol. 102, No. 4, 01.04.2007, p. 1490-1501.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Age-related changes in multifinger synergies in accurate moment of force production tasks

AU - Olafsdottir, Halla

AU - Zhang, Wei

AU - Zatsiorsky, Vladimir M.

AU - Latash, Mark L.

PY - 2007/4/1

Y1 - 2007/4/1

N2 - The purpose of this investigation was to document and quantify age-related differences in the coordination of fingers during a task that required production of an accurate time profile of the total moment of force by the four fingers of a hand. We hypothesized that elderly subjects would show a decreased ability to stabilize a time profile of the total moment of force, leading to larger indexes of moment variability compared with young subjects. The subjects followed a trapezoidal template on a computer screen by producing a time profile of the total moment of force while pressing down on force sensors with the four fingers of the right (dominant) hand. To quantify synergies, we used the framework of the uncontrolled manifold hypothesis. The elderly subjects produced larger total force, larger variance of both total force and total moment of force, and larger involvement of fingers that produced moment of force against the required moment direction (antagonist moment). This was particularly prominent during supination efforts. Young subjects showed covariation of commands to fingers across trials that stabilized the moment of total force (moment-stabilizing synergy), while elderly subjects failed to do so. Both subject groups showed similar indexes of covariation of commands to the fingers that stabilized the time profile of the total force. The lack of moment-stabilizing synergies may be causally related to the documented impairment of hand function with age.

AB - The purpose of this investigation was to document and quantify age-related differences in the coordination of fingers during a task that required production of an accurate time profile of the total moment of force by the four fingers of a hand. We hypothesized that elderly subjects would show a decreased ability to stabilize a time profile of the total moment of force, leading to larger indexes of moment variability compared with young subjects. The subjects followed a trapezoidal template on a computer screen by producing a time profile of the total moment of force while pressing down on force sensors with the four fingers of the right (dominant) hand. To quantify synergies, we used the framework of the uncontrolled manifold hypothesis. The elderly subjects produced larger total force, larger variance of both total force and total moment of force, and larger involvement of fingers that produced moment of force against the required moment direction (antagonist moment). This was particularly prominent during supination efforts. Young subjects showed covariation of commands to fingers across trials that stabilized the moment of total force (moment-stabilizing synergy), while elderly subjects failed to do so. Both subject groups showed similar indexes of covariation of commands to the fingers that stabilized the time profile of the total force. The lack of moment-stabilizing synergies may be causally related to the documented impairment of hand function with age.

UR - http://www.scopus.com/inward/record.url?scp=34147132419&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34147132419&partnerID=8YFLogxK

U2 - 10.1152/japplphysiol.00966.2006

DO - 10.1152/japplphysiol.00966.2006

M3 - Article

C2 - 17204576

AN - SCOPUS:34147132419

VL - 102

SP - 1490

EP - 1501

JO - Journal of Applied Physiology

JF - Journal of Applied Physiology

SN - 8750-7587

IS - 4

ER -