Title
Yaw Postural Perturbation Through Robotic Platform: Aging Effects on Muscle Synergies.
Abstract
Aging causes a worsening in muscle system, which could cause balance impairments, increasing the risk of falls. The study aims at evaluating the effects of aging on muscle activation in response to a yaw rotation imposed by the RotoBiT 1D . Eight younger and eight older adults were enrolled in the study. A right sigmoidal rotation of 55° around the yaw axis was imposed to the subject by means of the RotoBiT 1D platform in two velocity conditions, characterized by an angular velocity peak equal to 80¼/s and 100 °/s, respectively. The activations of 16 bilateral muscles of upper body were recorded through wireless surface electromyography. A Non-Negative Matrix Factorization was performed to extract the muscle synergies. The number of muscle synergies was selected by using the Variability Account For. The cosine of similarity was computed for the quantification of intra-group and inter-group similarity related to the muscle synergy vectors. The number of muscle synergies ranged from 4 to 6 in younger and from 3 to 6 in older, even though no statistical difference was found between groups or velocity conditions. As regards intra-group similarity, younger adults showed values always above the similarity threshold; while a lower similarity was observed in older adults, confirming the heterogeneity of postural response. The overall structure of muscle synergy vectors was not similar between groups and the inter-group similarity decreased with the increase of the velocity. The differences were greater in synergies involving head and upper limb muscles. Findings unveiled a different muscle synergy organization in terms of muscle synergy vectors. Such a different organization calls for a deeper investigation towards the aim of identifying causes of fall in elderly.
Year
Venue
Field
2018
BioRob
Statistical difference,Angular velocity,Aircraft principal axes,Matrix decomposition,Electromyography,Muscle activation,Physical medicine and rehabilitation,Yaw,Mathematics,Perturbation (astronomy)
DocType
Citations 
PageRank 
Conference
0
0.34
References 
Authors
0
5
Name
Order
Citations
PageRank
Juri Taborri1669.41
Ilaria Mileti200.34
Zaccaria Del Prete3910.45
Rossi, S.43915.50
Eduardo Palermo58415.96