کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
928647 922379 2011 18 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Sensori-motor integration during stance: Time adaptation of control mechanisms on adding or removing vision
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب شناختی
پیش نمایش صفحه اول مقاله
Sensori-motor integration during stance: Time adaptation of control mechanisms on adding or removing vision
چکیده انگلیسی

Sudden addition or removal of visual information can be particularly critical to balance control. The promptness of adaptation of stance control mechanisms is quantified by the latency at which body oscillation and postural muscle activity vary after a shift in visual condition. In the present study, volunteers stood on a force platform with feet parallel or in tandem. Shifts in visual condition were produced by electronic spectacles. Ground reaction force (center of foot pressure, CoP) and EMG of leg postural muscles were acquired, and latency of CoP and EMG changes estimated by t-tests on the averaged traces. Time-to-reach steady-state was estimated by means of an exponential model. On allowing or occluding vision, decrements and increments in CoP position and oscillation occurred within about 2 s. These were preceded by changes in muscle activity, regardless of visual-shift direction, foot position or front or rear leg in tandem. These time intervals were longer than simple reaction-time responses. The time course of recovery to steady-state was about 3 s, shorter for oscillation than position. The capacity of modifying balance control at very short intervals both during quiet standing and under more critical balance conditions speaks in favor of a necessary coupling between vision, postural reference, and postural muscle activity, and of the swiftness of this sensory reweighing process.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Human Movement Science - Volume 30, Issue 2, April 2011, Pages 172–189
نویسندگان
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