Document Detail


Age-related changes in the control of finger force vectors.
MedLine Citation:
PMID:  20829494     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We explored changes in finger interaction in the process of healthy aging as a window into neural control strategies of natural movements. In particular, we quantified the amount of force produced by noninstructed fingers in different directions, the amount of force produced by the instructed finger orthogonally to the task direction, and the strength of multifinger synergies stabilizing the total force magnitude and direction during accurate force production. Healthy elderly participants performed accurate isometric force production tasks in five directions by individual fingers and by all four fingers acting together. Their data were compared with a dataset obtained in a similar earlier study of young subjects. Finger force vectors were measured using six-component force/torque sensors. Multifinger synergies were quantified using the framework of the uncontrolled manifold hypothesis. The elderly participants produced lower force magnitudes by noninstructed fingers and higher force magnitudes by instructed fingers in nontask directions. They showed strong synergies stabilizing the magnitude and direction of the total force vector. However, the synergy indexes were significantly lower than those observed in the earlier study of young subjects. The results are consistent with an earlier hypothesis of preferential weakening of intrinsic hand muscles with age. We interpret the findings as a shift in motor control from synergic to element-based, which may be causally linked to the documented progressive neuronal death at different levels of the neural axis.
Authors:
Shweta Kapur; Vladimir M Zatsiorsky; Mark L Latash
Related Documents :
19452144 - Finger force enslaving and surplus in spinal cord injury patients.
12574444 - Importance of cutaneous feedback in maintaining a secure grip during manipulation of ha...
11404214 - Stability in force-production tasks.
20186284 - The principle of superposition in human prehension.
17108094 - A population coding account for systematic variation in saccadic dead time.
9256114 - Motion-adapted gating based on k-space weighting for reduction of respiratory motion ar...
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, N.I.H., Extramural     Date:  2010-09-09
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  109     ISSN:  1522-1601     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  2010 Dec 
Date Detail:
Created Date:  2010-12-14     Completed Date:  2011-03-25     Revised Date:  2011-12-21    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1827-41     Citation Subset:  IM    
Affiliation:
Department of Kinesiology, The Pennsylvania State University, University Park, PA 16802, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Age Factors
Aged
Aging*
Analysis of Variance
Biomechanics
Female
Fingers
Humans
Isometric Contraction*
Male
Models, Biological
Motor Activity*
Muscle Strength*
Muscle, Skeletal / innervation,  physiology*
Task Performance and Analysis
Torque
Transducers, Pressure
Grant Support
ID/Acronym/Agency:
AG-018751/AG/NIA NIH HHS; AR-048563/AR/NIAMS NIH HHS; NS-035032/NS/NINDS NIH HHS

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


Previous Document:  Power loss is greater in old men than young men during fast plantar flexion contractions.
Next Document:  Length oscillation mimicking periodic individual deep inspirations during tidal breathing attenuates...