Putative spinal interneurons mediating postural limb reflexes provide a basis for postural control in different
Pavel V Zelenin1, Li-Ju Hsu, Vladimir F Lyalka
1Department of Neuroscience, Karolinska Institute, SE-17177, Stockholm, Sweden.
The European Journal of Neuroscience
|November 6, 2014
Summary
Spinal neurons control quadrupedal posture through postural limb reflexes (PLRs). This study maps these neurons and their sensory input, revealing how they stabilize body orientation.
Area of Science:
- Neuroscience
- Motor Control
- Spinal Cord Physiology
Background:
- Quadrupedal standing posture relies on somatosensory limb input.
- Postural limb reflexes (PLRs) are crucial for maintaining trunk orientation.
- Previous work identified spinal neurons involved in PLRs.
Purpose of the Study:
- Map the distribution of PLR-related spinal neurons.
- Analyze sensory input convergence from limbs onto these neurons.
- Determine neuronal contribution to body orientation stabilization.
Main Methods:
- Recorded L5-L6 spinal neuron activity in decerebrate rabbits.
- Evoked PLRs using lateral platform tilts.
- Tested responses to ipsilateral, contralateral, and in-phase limb stimulation.
Main Results:
- PLR activity and ipsilateral input strength decreased dorsoventrally.
- Contralateral limb input strength increased dorsoventrally.
- Demonstrated near linear summation of sensory inputs from different limbs.
Conclusions:
- Characterized posture-related spinal neurons and their sensory integration.
- Established a foundation for studying spinal postural networks.
- Provided insights into neuronal roles in body orientation stabilization.
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