Document Detail

Anticipatory synergy adjustments in preparation to self-triggered perturbations in elderly individuals.
MedLine Citation:
PMID:  18579910     Owner:  NLM     Status:  MEDLINE    
We tested the ability of healthy elderly persons to use anticipatory synergy adjustments (ASAs) prior to a self-triggered perturbation of one of the fingers during a multifinger force production task. An index of a force-stabilizing synergy was computed reflecting covariation of commands to fingers. The subjects produced constant force by pressing with the four fingers of the dominant hand on force sensors against constant upwardly directed forces. The middle finger could be unloaded either by the subject pressing the trigger or unexpectedly by the experimenter. In the former condition, the synergy index showed a drop (interpreted as ASA) prior to the time of unloading. This drop started later and was smaller in magnitude as compared with ASAs reported in an earlier study of younger subjects. At the new steady state, a new sharing pattern of the force was reached. We conclude that aging is associated with a preserved ability to explore the flexibility of the mechanically redundant multifinger system but a decreased ability to use feedforward adjustments to self-triggered perturbations. These changes may contribute to the documented drop in manual dexterity with age.
Halla B Olafsdottir; Sun Wook Kim; Vladimir M Zatsiorsky; Mark L Latash
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural    
Journal Detail:
Title:  Journal of applied biomechanics     Volume:  24     ISSN:  1065-8483     ISO Abbreviation:  J Appl Biomech     Publication Date:  2008 May 
Date Detail:
Created Date:  2008-06-26     Completed Date:  2008-09-23     Revised Date:  2014-09-20    
Medline Journal Info:
Nlm Unique ID:  9315240     Medline TA:  J Appl Biomech     Country:  United States    
Other Details:
Languages:  eng     Pagination:  175-9     Citation Subset:  IM    
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MeSH Terms
Aged, 80 and over
Aging / physiology
Fingers / physiology*
Hand Strength / physiology*
Muscle Contraction / physiology*
Psychomotor Performance / physiology*
Grant Support
AG-018751/AG/NIA NIH HHS; AR-048563/AR/NIAMS NIH HHS; M01 RR-10732/RR/NCRR NIH HHS; NS-035032/NS/NINDS NIH HHS; R01 AG018751/AG/NIA NIH HHS; R01 AG018751-07/AG/NIA NIH HHS; R01 AR048563/AR/NIAMS NIH HHS; R01 AR048563-05/AR/NIAMS NIH HHS; R01 NS035032/NS/NINDS NIH HHS; R01 NS035032-11/NS/NINDS NIH HHS

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

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