TY - JOUR
T1 - Finger coordination in persons with Down syndrome
T2 - Atypical patterns of coordination and the effects of practice
AU - Latash, Mark L.
AU - Kang, Ning
AU - Patterson, David
N1 - Funding Information:
Acknowledgements We are very grateful to the Mile High Down Syndrome Association, Denver, CO, and to all the participants in the study and their families for their exceptional patience and cooperation. This study was supported in part by a grant from the Coleman Institute for Cognitive Disabilities at the University of Colorado and by NIH grants NS-35032 and HD-17449.
PY - 2002
Y1 - 2002
N2 - The study addresses an issue of possible relations between the apparent "clumsiness" of persons with Down syndrome (DS) and changes in indices of finger coordination. We hypothesized that persons with DS would prefer less challenging, safer motor strategies reflected in finger coordination patterns. Maximal single-and multi-finger force production (MVC) tasks and multi-finger tasks that required the production of a controlled time pattern (ramp) of total force were studied. As compared to typical persons, persons with DS showed lower peak forces, lower force deficit (loss of finger force in multi-finger tasks as compared to single-finger tasks), and higher enslaving (involuntary force production by fingers that are not required to produce force). They showed higher variance of total force computed across several trials for ramp tasks. Their total force variance was higher than the sum of the variances of individual finger forces over the ramp duration, while in control participants the relation was opposite during the middle and late thirds of the ramp. Persons with DS practiced force production tasks over 3 days, one group practicing only one of the tasks (the ramp task with all four fingers acting together) while the other group practiced MVC and ramp tasks (variable practice). Practice led to an increase in MVC, force deficit, and enslaving. The relation between the total force variance and the sum of the variances of individual finger forces became closer to the one observed in typical persons. The effects of practice were more pronounced in the variable practice group. We conclude that persons with DS have a deficit in control of both single fingers and multi-finger groups. They use a less challenging, suboptimal strategy of multi-finger coordination which does not take advantage of the possibility of error compensation among the fingers. Practice is an effective way of improving finger coordination in DS, particularly when using variable tasks.
AB - The study addresses an issue of possible relations between the apparent "clumsiness" of persons with Down syndrome (DS) and changes in indices of finger coordination. We hypothesized that persons with DS would prefer less challenging, safer motor strategies reflected in finger coordination patterns. Maximal single-and multi-finger force production (MVC) tasks and multi-finger tasks that required the production of a controlled time pattern (ramp) of total force were studied. As compared to typical persons, persons with DS showed lower peak forces, lower force deficit (loss of finger force in multi-finger tasks as compared to single-finger tasks), and higher enslaving (involuntary force production by fingers that are not required to produce force). They showed higher variance of total force computed across several trials for ramp tasks. Their total force variance was higher than the sum of the variances of individual finger forces over the ramp duration, while in control participants the relation was opposite during the middle and late thirds of the ramp. Persons with DS practiced force production tasks over 3 days, one group practicing only one of the tasks (the ramp task with all four fingers acting together) while the other group practiced MVC and ramp tasks (variable practice). Practice led to an increase in MVC, force deficit, and enslaving. The relation between the total force variance and the sum of the variances of individual finger forces became closer to the one observed in typical persons. The effects of practice were more pronounced in the variable practice group. We conclude that persons with DS have a deficit in control of both single fingers and multi-finger groups. They use a less challenging, suboptimal strategy of multi-finger coordination which does not take advantage of the possibility of error compensation among the fingers. Practice is an effective way of improving finger coordination in DS, particularly when using variable tasks.
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U2 - 10.1007/s00221-002-1189-3
DO - 10.1007/s00221-002-1189-3
M3 - Article
C2 - 12232691
AN - SCOPUS:0036383397
SN - 0014-4819
VL - 146
SP - 345
EP - 355
JO - Experimental Brain Research
JF - Experimental Brain Research
IS - 3
ER -