Motoneuronal and muscle synergies involved in cat hindlimb control
نویسندگان
چکیده
23 We compared the activity profiles and synergies of spinal motoneurons recorded during 24 fictive locomotion evoked in immobilized decerebrate cat preparations by midbrain stimulation 25 to the activity profiles and synergies of the corresponding hindlimb muscles obtained during 26 forward level walking in cats. The fictive locomotion data were collected in the Spinal Cord 27 Research Centre, University of Manitoba, and provided by Dr. McCrea; the real locomotion data 28 were obtained in the laboratories of Drs. Lemay and Prilutsky. Scatter plot representation and 29 Minimum Spanning Tree clustering algorithm were used to identify the possible motoneuronal 30 and muscle synergies operating during both fictive and real locomotion. We found a close 31 similarity between the activity profiles and synergies of motoneurons innervating one-joint 32 muscles during fictive locomotion and the profiles and synergies of the corresponding muscles 33 during real locomotion. However, the activity patterns of proximal nerves controlling two-joint 34 muscles, such as the posterior biceps and semitendinosus (PBSt) and rectus femoris (RF), were 35 not uniform in fictive locomotion preparations and differed from the activity profiles of the 36 corresponding two-joint muscles recorded during forward level walking. Moreover, the activity 37 profiles of these nerves and the corresponding muscles were unique and could not be included in 38 the synergies identified in fictive and real locomotion. We suggest that afferent feedback is 39 involved in the regulation of locomotion via motoneuronal synergies controlled by the spinal 40 central pattern generator (CPG), but may also directly affect the activity of motoneuronal pools 41 serving two-joint muscles (e.g., PBSt and RF). These findings provide important insights into the 42 organization of the spinal CPG in mammals, the motoneuronal and muscle synergies engaged 43 during locomotion, and their afferent control. 44 45
منابع مشابه
Motoneuronal and muscle synergies involved in cat hindlimb control during fictive and real locomotion: a comparison study.
We compared the activity profiles and synergies of spinal motoneurons recorded during fictive locomotion evoked in immobilized decerebrate cat preparations by midbrain stimulation to the activity profiles and synergies of the corresponding hindlimb muscles obtained during forward level walking in cats. The fictive locomotion data were collected in the Spinal Cord Research Centre, University of ...
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