Extended Data Fig. 7: Augmented muscle afferents restore neuromodulation of biomimetic stair adaptation.

a, CTL and AMI cohort averaged torque-angle trajectories on the staircase with varying levels of residual muscle afferents are plotted as: non-biomimetic (n = 4 CTL), low level (n = 3 CTL), moderate level (n = 3 AMI), and high level (n = 4 AMI). Corresponding agonist-antagonist muscle afferents for each group are reported (mean ± SEM). For comparison, a biologically-intact ankle torque-angle trajectory is shown on the right¹¹. Due to the lack of data points for the torque-angle trajectory plot, the dotted line for the biologically-intact limb plot extends from the original data¹¹. Note, as residual muscle afferents were augmented, the evolving neuromodulated bionic gait moved toward natural stair adaptation. b, All subjects’ bionic functional metrics in the stair adaptation are plotted against their agonist-antagonist muscle afferents. Negative peak power values are reported for stair descent, whereas positive peak power values are reported for stair ascent. Net work during weight acceptance and pull-up are reported for stair descent and ascent, respectively. Pearson correlations (\(r\)), 95% CI, and slopes (m) are reported (n = 14, *P = 0.035, **P < 0.0069, ***P < 6.8\(\times\)10^-4).