Age-related modifications of muscle synergies and spinal cord activity during locomotion.

@article{Monaco2010AgerelatedMO,
  title={Age-related modifications of muscle synergies and spinal cord activity during locomotion.},
  author={Vito Monaco and A. Ghionzoli and Silvestro Micera},
  journal={Journal of neurophysiology},
  year={2010},
  volume={104 4},
  pages={
          2092-102
        }
}
Recent findings have shown that neural circuits located in the spinal cord drive muscular activations during locomotion while intermediating between descending signals and peripheral sensory information. This relationship could be modified by the natural aging process. To address this issue, the activity of 12 ipsilateral leg muscles was analyzed in young and elderly people (7 subjects per group) while walking at six different cadences (40-140 steps/min). These signals were used to extract… 
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References

SHOWING 1-10 OF 62 REFERENCES
Spinal cord maps of spatiotemporal alpha-motoneuron activation in humans walking at different speeds.
TLDR
A striking feature is that nearly every spinal segment undergoes at least two cycles of activation in the step cycle, thus supporting the idea of half-center oscillators controlling MN activation at any segmental level.
Muscle synergies during locomotion in the cat: a model for motor cortex control
TLDR
It is suggested that subpopulations of motor cortical neurones may regulate the activity of small groups of synergistic muscles, likewise active sequentially throughout the step cycle, thus providing a flexible substrate for the control of intralimb coordination during locomotion.
Distributed plasticity of locomotor pattern generators in spinal cord injured patients.
TLDR
Recovery of foot kinematics in SCI patients may not be subserved by changes localized to limited regions of the spinal cord, but may depend on a plastic redistribution of activity across most of the rostrocaudal extent ofThe spinal cord.
Spatiotemporal organization of α‐motoneuron activity in the human spinal cord during different gaits and gait transitions
TLDR
The results overall support the idea of flexibility and adaptability of spatiotemporal activity in the spinal circuitry with constraints on the temporal functional connectivity of hypothetical pulsatile burst generators.
Muscle synergies during walking: Comparison between young and elderly people. Preliminary results
TLDR
Results showed that young and elderly muscle activations were described by factors behaving in opposite manner between the groups, suggesting that ageing may involve modifications in the peripheral areas of the Central Nervous System, producing neuromuscular adaptation.
Merging of healthy motor modules predicts reduced locomotor performance and muscle coordination complexity post-stroke.
TLDR
A common modular organization of muscle coordination underlying walking in both healthy and post-stroke subjects is suggested, which may lead to new insight into impaired locomotor coordination and the underlying neural systems.
Five basic muscle activation patterns account for muscle activity during human locomotion
TLDR
A systematic phase shift of all five factors with speed in the same direction as the shift in the onset of the swing phase supports the idea that the origin of the gait cycle generation is the propulsion rather than heel strike event.
Spatiotemporal activation of lumbosacral motoneurons in the locomotor step cycle.
TLDR
A dynamic model of the spatiotemporal activation of ensembles of alpha motoneurons (MNs) in the cat lumbosacral spinal cord during the locomotor step cycle is produced and the distribution of neuronal activity in the spinal cords during normal locomotion with descending control and sensory inputs intact has not been visualized before.
Motor patterns in human walking and running.
TLDR
The results are consistent with an organization of locomotion motor programs having two parts, one that organizes muscle activation during swing and another during stance and the transition to swing, and the timing shift between walking and running reflects the difference in the relative duration of the stance phase in the two gaits.
Progress of age-related changes in properties of motor units in the gastrocnemius muscle of rats.
TLDR
The findings indicated that the progress of changes in various properties occurring in the senescent muscle was different in terms of their time course and degree and also dependent on the types of motor unit.
...
1
2
3
4
5
...