Figure 10

Effects of transspinal stimulation on shank-foot coordination during walking. (a–d) Continuous relative phase curves for left and right shank-foot intralimb coordination with transspinal stimulation and during control walking. Negative curve (°) indicates that the proximal segment is ahead of the distal segment in phase space. A negative slope indicates that the proximal segment moves faster than the distal segment, while a positive slope indicates that the distal segment moves faster than the proximal segment. A value of 0° indicates an in-phase relationship of the coupling, while a value of 180° indicates an anti-phase relationship. Solid lines represent group average. (e) Vertical bars display which gait phases affected by transspinal stimulation in relation to intralimb coordination. (f) Horizontal stacked bars display the cumulative number of transspinal stimulation effects on intralimb coordination for each gait phase. A positive (+) sign represents a shift to a greater anti-phase pattern, and a negative (−) sign a shift to a greater in-phase pattern. (g) Each row corresponds to a specific gait phase, and each column represents a distinct set of gait phases. Black dots signify gait phases in which transspinal stimulation had significant effect on intralimb coordination compared to control walking. Multiple black dots in columns indicate significant transspinal stimulation effects across different gait phases. (h) Stick figures of representative stride of a subject during walking. The red parts of the stick figures correspond to the phase where the thigh moves faster than the foot in phase space, and the blue parts where the foot moves faster than the thigh. SUB sub-threshold, SUP supra-threshold, IC initial contact, LR loading response, MS midstance, TS terminal stance, PSw pre-swing; ISw initial swing, MSw mid-swing, TSw terminal swing.