Document Detail


The use of peripheral vision to guide perturbation-evoked reach-to-grasp balance-recovery reactions.
MedLine Citation:
PMID:  20957351     Owner:  NLM     Status:  In-Process    
Abstract/OtherAbstract:
For a reach-to-grasp reaction to prevent a fall, it must be executed very rapidly, but with sufficient accuracy to achieve a functional grip. Recent findings suggest that the CNS may avoid potential time delays associated with saccade-guided arm movements by instead relying on peripheral vision (PV). However, studies of volitional arm movements have shown that reaching is slower and/or less accurate when guided by PV, rather than central vision (CV). The present study investigated how the CNS resolves speed-accuracy trade-offs when forced to use PV to guide perturbation-evoked reach-to-grasp balance-recovery reactions. These reactions were evoked, in 12 healthy young adults, via sudden unpredictable antero-posterior platform translation (barriers deterred stepping reactions). In PV trials, subjects were required to look straight-ahead at a visual target while a small cylindrical handhold (length 25%> hand-width) moved intermittently and unpredictably along a transverse axis before stopping at a visual angle of 20°, 30°, or 40°. The perturbation was then delivered after a random delay. In CV trials, subjects fixated on the handhold throughout the trial. A concurrent visuo-cognitive task was performed in 50% of PV trials but had little impact on reach-to-grasp timing or accuracy. Forced reliance on PV did not significantly affect response initiation times, but did lead to longer movement times, longer time-after-peak-velocity and less direct trajectories (compared to CV trials) at the larger visual angles. Despite these effects, forced reliance on PV did not compromise ability to achieve a functional grasp and recover equilibrium, for the moderately large perturbations and healthy young adults tested in this initial study.
Authors:
Emily C King; Sandra M McKay; Kenneth C Cheng; Brian E Maki
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-10-19
Journal Detail:
Title:  Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale     Volume:  207     ISSN:  1432-1106     ISO Abbreviation:  Exp Brain Res     Publication Date:  2010 Nov 
Date Detail:
Created Date:  2010-10-27     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0043312     Medline TA:  Exp Brain Res     Country:  Germany    
Other Details:
Languages:  eng     Pagination:  105-18     Citation Subset:  IM    
Affiliation:
Centre for Studies in Aging, Sunnybrook Health Sciences Centre, Toronto, ON, Canada. Emily.King@UToronto.ca
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Grant Support
ID/Acronym/Agency:
#MOP-13355//Canadian Institutes of Health Research; 13355//Canadian Institutes of Health Research

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


Previous Document:  Extrasynaptic GABA(A) receptor activation reverses recognition memory deficits in an animal model of...
Next Document:  Effects of cadmium and phenanthrene mixtures on aquatic fungi and microbially mediated leaf litter d...