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Feedback Regulation Of Temporal Muscle Activation Patterns For Postural Control Before And After Peripheral Neuropathy, L Ting, D Lockhart, P Stapley, J Macpherson
Feedback Regulation Of Temporal Muscle Activation Patterns For Postural Control Before And After Peripheral Neuropathy, L Ting, D Lockhart, P Stapley, J Macpherson
Dr Paul J Stapley
Introduction: Neural mechanislllS determining temporal pattcl1ls of muscle activity during poshlral responses are not understood. Fulluwing pyridoxine inuuced somatosensory loss in cats, unset latencies of automatic poshu-al responses are delayed, and balance is impaired. We introduce a new method for correlating temporal patterns of muscle activation with task-level variahles in the context of postural responses to perturbation. Methods: We measured postmal responses to support smface tronslations before and after loss of group I afferents indnced by pyridoxine intoxication. We reconstructed temporal EMG patterns llsing a feedback loop with delays, on CoM acceleration. velocity, and displacement. Resnlts: Prior to lesion, temporal …
Independent Activation In Adjacent Lumbar Extensor Muscle Compartments, Marilee Nugent, Paul Stapley, Theodore Milner
Independent Activation In Adjacent Lumbar Extensor Muscle Compartments, Marilee Nugent, Paul Stapley, Theodore Milner
Dr Paul J Stapley
The purpose of this study was to examine compartmentalization in human lumbar spine extensors. Structure and innervation of these muscles would suggest the possibility of more segmentally specific biomechanical functions than have been found in previous studies examining muscle activation patterns during simple spine bending and twisting tasks. We selected specialized tasks to more effectively investigate the degree of independent control possible within lumbar spine extensors. We recorded surface electromyograms (SEMG) from the right posterior lumbar region during performance of two segmentally specific bellydance skills by seven novice and five trained subjects. These movements were performed at two frequencies (0.5 …