Fig. 11.
“Persistence” vs. “no persistence” of the entrained gait period. A: persistence. Representative subject shows entrained gait with no significant difference in stride duration during and after perturbation. B: no persistence. Representative subject shows entrained gait with significant difference in stride duration during and after, as well as before and after, perturbation (i.e., stride period had started to drift back to its preferred value). C: no persistence. Representative subject shows entrained gait with significant difference in stride duration during and after perturbation, but no significant difference before and after perturbation (i.e., stride period had fully returned to its preferred value). This behavior was only observed in TM trials. D: exponential fit of the difference in stride period during and after perturbation as a function of the strides walked at the entrained gait period after convergence: |τduring − τafter| = 281·e−0.156·strides, R2 = 0.9.