Potential role of a ventral nerve cord central pattern generator in forward and backward locomotion in Caenorhabditis elegans

@article{Olivares2018PotentialRO,
  title={Potential role of a ventral nerve cord central pattern generator in forward and backward locomotion in Caenorhabditis elegans},
  author={Erick Olivares and Eduardo J. Izquierdo and Randall D. Beer},
  journal={Network Neuroscience},
  year={2018},
  volume={2},
  pages={323 - 343}
}
C. elegans locomotes in an undulatory fashion, generating thrust by propagating dorsoventral bends along its body. Although central pattern generators (CPGs) are typically involved in animal locomotion, their presence in C. elegans has been questioned, mainly because there has been no evident circuit that supports intrinsic network oscillations. With a fully reconstructed connectome, the question of whether it is possible to have a CPG in the ventral nerve cord (VNC) of C. elegans can be… 
A Neuromechanical Model of Multiple Network Rhythmic Pattern Generators for Forward Locomotion in C. elegans
TLDR
A simulation model is used to search for parameters of the anatomically constrained ventral nerve cord circuit that, when embodied and situated, can drive forward locomotion on agar, in the absence of pacemaker neurons or stretch-receptor feedback.
A neuromechanical model of multiple network rhythmic pattern generators for forward locomotion in C. elegans
TLDR
A simulation model is used to search for parameters of the anatomically constrained ventral nerve cord circuit that, when embodied and situated, can drive forward locomotion on agar, in the absence of pacemaker neurons or stretch-receptor feedback.
From head to tail: a neuromechanical model of forward locomotion in Caenorhabditis elegans
  • E. Izquierdo, R. Beer
  • Medicine, Biology
    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2018
TLDR
Analysis of the development and analysis of a model of forward locomotion that integrates the neuroanatomy, neurophysiology and body mechanics of the worm revealed that head motoneurons SMD and RMD are sufficient to drive dorsoventral undulations in the head and neck and that short-range posteriorly directed proprioceptive feedback is sufficient to propagate the wave along the rest of the body.
From head to tail: A neuromechanical model of forward locomotion in C. elegans
TLDR
Analysis of the development and analysis of a model of forward locomotion that integrates the neuroanatomy, neurophysiology and body mechanics of the worm revealed that head motoneurons SMD and RMD are sufficient to drive dorsoventral undulations in the head and neck and that short-range posteriorly-directed proprioceptive feedback is sufficient to propagate the wave along the rest of the body.
Forward and backward locomotion patterns in C. elegans generated by a connectome-based model simulation
TLDR
A connectome-based neural network model consisting of motor neurons of classes A, B, D, AS, and muscle, considering both synaptic and gap connections is presented, which can be trained to reproduce the activity patterns measured for an animal (HRB4 strain).
Caenorhabditis elegans excitatory ventral cord motor neurons derive rhythm for body undulation
TLDR
It is proposed that the A- and mid-body B-class excitatory motor neurons at the ventral cord function as non-bursting intrinsic oscillators to underlie body undulation during reversal and forward movements, respectively, and implicate a circuit-level functional compression.
Optogenetic analysis of Ca++ transients in Caenorhabditis elegans muscle cells during forward and reverse locomotion
TLDR
There is significantly different mean Ca++ levels in many of the muscle cells during forward and reverse locomotion and, when considered independently, the dorsal and ventral muscle activation waves exhibit classical neuromechanical phase lag (NPL).
Inhibition Underlies Fast Undulatory Locomotion in Caenorhabditis elegans
TLDR
The experimental results suggest at least three non-mutually exclusive roles for inhibition that could underlie fast undulatory locomotion in C. elegans, which were tested with computational models: cross-inhibition or disinhibition of body-wall muscles, or neuronal reset.
Signatures of proprioceptive control in Caenorhabditis elegans locomotion
TLDR
A computational model is used to identify effects of neural and mechanical modulation on undulatory forward locomotion of Caenorhabditis elegans, with a focus on proprioceptively driven neural control, and reveals a fundamental relationship between body elasticity and environmental drag in determining the dynamics of the body.
Signatures of proprioceptive control in C. elegans locomotion
Animal neuromechanics describes the coordinated self-propelled movement of a body, subject to the combined effects of internal neural control and mechanical forces. Here we use a computational model
...
1
2
3
...

References

SHOWING 1-10 OF 77 REFERENCES
Synaptic polarity of the interneuron circuit controlling C. elegans locomotion
TLDR
The likely polarities of seven pre-motor neurons implicated in the control of worm's locomotion are deciphered, using a combination of experimental and computational tools to suggest that inhibition governs the dynamics of the locomotor interneuron circuit.
Neural control of Caenorhabditis elegans forward locomotion: the role of sensory feedback
TLDR
A simple yet biologically-grounded model for the neural control of Caenorhabditis elegans forward locomotion finds that a minimal circuit of AVB interneurons and B-class motoneurons is sufficient to generate and sustain fictiveforward locomotion patterns that are robust to significant environmental perturbations.
Gait Modulation in C. elegans: An Integrated Neuromechanical Model
TLDR
A model of C. elegans forward locomotion is presented that includes a neuromuscular control system that relies on a sensory feedback mechanism to generate undulations and is integrated with a physical model of the body and environment and reproduces the entire swim-crawl transition with no modulatory mechanism.
A descending pathway facilitates undulatory wave propagation in Caenorhabditis elegans through gap junctions
TLDR
Combined experimental and computational analysis revealed that motor neurons in C. elegans could function as intrinsic oscillators, and descending inputs and proprioceptive couplings work synergistically to facilitate the sequential activation of motor neuron activities, allowing bending waves to propagate efficiently along the body.
Descending pathway facilitates undulatory wave propagation in Caenorhabditis elegans through gap junctions
TLDR
The combined experimental and computational analyses revealed that motor neurons in C. elegans function as oscillators; descending interneuron inputs and proprioceptive coupling between motor neurons work synergistically to facilitate the sequential activation of motor neuron activities, allowing bending waves to propagate efficiently along the body.
Neural network model to generate head swing in locomotion of Caenorhabditis elegans
Computer simulation of the neural network composed of the head neurons of Caenorhabditis elegans was performed to reconstruct the realistic changes in the membrane potential of motoneurons in
Evolution and Analysis of Minimal Neural Circuits for Klinotaxis in Caenorhabditis elegans
TLDR
A minimalistic neural network, comprised of an ON-OFF pair of chemosensory neurons and a pair of neck muscle motor neurons, is sufficient to generate realistic klinotaxis behavior, suggesting that the model may be operating according to principles similar to those of the biological network.
Central Pattern Generator for Locomotion: Anatomical, Physiological, and Pathophysiological Considerations
TLDR
This article constitutes a comprehensive review summarizing key findings on the CPG as well as on its potential role in Restless Leg Syndrome, Periodic Leg Movement, and Alternating Leg Muscle Activation.
Systems level circuit model of C. elegans undulatory locomotion: mathematical modeling and molecular genetics
TLDR
The model reveals that stretch receptor coupling in the body wall is critical for generation of the neuromuscular wave, and agrees with behavioral data and with other pertinent published data, e.g., that frequency is an increasing function of muscle gap-junction coupling.
...
1
2
3
4
5
...