| This thesis settles the open question of whether or not neuromuscular dynamics is mixing by showing evidence of both scenarios and demonstrates remarkable coherence properties between the dynamics in the neck and sacrum in healthy subjects and the absence of this feature in quadriplegic subjects. These results are shown from the analysis of data collected during an electrophysiological phenomenon running up and down the spine, elicited by light pressure contact at very precise points and thereafter taking the external appearance of an undulatory motion of the spine. This wave, called the spinal wave, results in a traveling and finally a standing wave pattern in the spine.;This research uses ergodic theory methods to analyze surface Electromyographic (sEMG) data during the spinal wave. The major tool used in this study is a construction known as special Euclidean (SE) extension. In this approach, the neuromuscular system is treated an abstract dynamical system and the sEMG sensors as observables. Properties of the system are analyzed from this observed data using special Euclidean extension of order 2.;These results, obtained using SE(2) analysis, are consistent with previous statistical studies of the spinal wave phenomenon. Finally, the thesis proposes some plausible models that might result in the spinal wave phenomenon. |
