Figure 5.
Kinematic modulation during locomotion along a runway versus treadmill-restricted stepping. A, Decomposition of hindlimb movements underlying both behavioral procedures at matched speeds. B, Average changes in hindlimb joint angles over the entire cohort of rats (n = 8 rats). C, PC analysis applied on all computed kinematic parameters distinguished gait patterns underlying locomotion along a runway versus stepping on a treadmill. Small purple or blue circles filled with different shades of gray represent average gait for each rat. D, Factor loading on PC1, which explained most of the variance between behaviors. Numbers correspond to raw kinematic parameters (see Materials and Methods). Plots reporting mean ± SEM values of the raw kinematic parameters that showed the highest correlation (factor loading) with PC1. Additionally, pelvis forward velocity over the entire gait cycle is shown. Two-sample t tests: #16: t(391) = 39, p < 1 × 10−10; #17: t(391) = −22.4, p < 1 × 10−10; pelvis: t(719) = 15, p < 1 × 10−10. ***Two-sample t test: p < 1 × 10−5 (Bonferroni correction for p < 0.05 with 126 comparisons is p < 7.9 × 10−5).