Split-Belt Walking Alters the Relationship between Locomotor Phases and Cycle Duration across Speeds in Intact and Chronic Spinalized Adult Cats
Split-Belt Walking Alters the Relationship between Locomotor Phases and Cycle Duration across Speeds in Intact and Chronic Spinalized Adult Cats
复制标题
DOI：
10.1523/jneurosci.3931-12.2013
复制
发表时间：
2013-05-08
影响因子：
5.3
通讯作者：
D'Angelo, Giuseppe
中科院分区：
文献类型：
--
作者：
Frigon, Alain;Hurteau, Marie-France;D'Angelo, Giuseppe
在地上或跑步机上行走时，站立阶段和周期持续时间随着速度的增加而减少，而摆动阶段持续时间保持相对不变。当左侧和右侧的速度不相等时，如在分裂带运动期间或当沿沿着圆形路径行走时的情况，观察到站立和摆动相位的调整，这可能改变相位/周期持续时间关系。在这里，我们在四只完整的成年猫和两只慢性脊髓横断的成年猫的左后肢和右后肢中测试了这一假设。相等的左和右速度）和分裂带（即，左右速度不等）行走。在分裂带行走期间，一侧（即，恒定肢体）以恒定速度行走，而另一侧（变化肢体）的速度从0.3到1.0 m/s变化。我们发现，阶段/周期持续时间的关系不同，在两个后肢同时在分裂带行走。具体而言，在不同的肢体从绑带分裂带步行的立场/伸展阶段的阶段/周期持续时间关系的斜率增加，而摆动/屈曲阶段下降。与此相反，在恒定的肢体中，站立/伸展阶段的相位/周期持续时间关系的斜率下降，而摆动/屈曲阶段的斜率增加。在完整和脊髓横断猫的结果是定性相似的，表明调制内脊髓介导的。总之，我们提出，脊髓内的神经元网络，控制左，右后肢运动可以差分，同时调制相位变化时，双方走在不同的速度。
During overground or treadmill walking, the stance phase and cycle durations are reduced as speed increases, whereas swing phase duration remains relatively invariant. When the speed of the left and right sides is unequal, as is the case during split-belt locomotion or when walking along a circular path, adjustments in stance and swing phases are observed, which could alter the phase/cycle duration relationships. Here, we tested this hypothesis in the left and right hindlimbs of four intact and two chronic spinal-transected adult cats during tied-belt (i.e., equal left and right speeds) and split-belt (i.e., unequal left and right speeds) walking. During split-belt walking, one side (i.e., constant limb) walked at a constant speed while the other side (varying limb) varied its speed from 0.3 to 1.0 m/s. We show that the phase/cycle duration relationships differed in both hindlimbs concurrently during split-belt walking. Specifically, the slope of the phase/cycle duration relationships for the stance/extension phase increased in the varying limb from tied-belt to split-belt walking, whereas that of the swing/flexion phase decreased. In contrast, in the constant limb, the slope of the phase/cycle duration relationships for the stance/extension phase decreased, whereas that of the swing/flexion phase increased. The results were qualitatively similar in intact and spinal-transected cats, indicating that the modulation was mediated within the spinal cord. In conclusion, we propose that neuronal networks within the spinal cord that control left and right hindlimb locomotion can differentially and simultaneously modulate phase variations when the two sides walk at different speeds.