Advanced

The Double Feedback Model of Neural Control of Locomotion: Is Immature Behavior Needed to Develop Mature Behavior?

Selbing, Ida LU (2011) KOGM20 20111
Cognitive Science
Abstract
Computational modeling is a commonly used method to understand, predict and explain for instance the organization of neuronal connectivity. Here it is applied to the problem of the development of the neural control of locomotion. Locomotion, e.g. walking and swimming, can be characterized as an alternate activation of opposing muscles and is controlled by central pattern generators, CPGs, in the spinal cord that function as relay centers for ascending and descending information. At the onset of development, rhythmic bursts of movements can be seen in the embryo of many species, humans included. These movements have been thoroughly studied in the chick and are believed to be generated by population dynamics in the chick spinal cord due to a... (More)
Computational modeling is a commonly used method to understand, predict and explain for instance the organization of neuronal connectivity. Here it is applied to the problem of the development of the neural control of locomotion. Locomotion, e.g. walking and swimming, can be characterized as an alternate activation of opposing muscles and is controlled by central pattern generators, CPGs, in the spinal cord that function as relay centers for ascending and descending information. At the onset of development, rhythmic bursts of movements can be seen in the embryo of many species, humans included. These movements have been thoroughly studied in the chick and are believed to be generated by population dynamics in the chick spinal cord due to a hyperexcited spinal network. However, the developing spinal cord undergoes a transition and already early in development, are embryonic movements generated by a CPG network. This paper shows a possible route to develop a model of the possible embryonic development from a hyperexcited spinal network to a central pattern generator. A first model of this is presented, the double feedback model, which includes a developing spinal network and a joint with opposing muscles, all connected by motoneurons and proprioceptic sensory neurons. The hypothesis presented suggests that two types of feedback are required for the development of a functional CPG network, connections directly from the motoneurons to spinal interneurons, more specifically inhibitory R-interneurons (the avian homolog to Renshaw neurons) and sensory connections from the muscle to the spinal network. The idea that sensory afferents can affect or at least tune the development of the neural circuit has been suggested earlier but results are not conclusive. Experiments that aim at evaluating the behavior of the double feedback model at different phases in the embryonic development of locomotion show that even though no alternate behavior similar to that of a CPG develops, the model is still in many cases able to generate a behavior that could be expected in the early embryonic development of the spinal cord. The double feedback model is thus able to capture some, but not all features of the developing spinal cord and can very well serve as a starting point for further development. (Less)
Please use this url to cite or link to this publication:
author
Selbing, Ida LU
supervisor
organization
course
KOGM20 20111
year
type
H2 - Master's Degree (Two Years)
subject
keywords
central pattern generators, spinal cord, neural networks, developing networks, motor control
language
English
id
1982072
date added to LUP
2011-06-23 16:25:12
date last changed
2011-06-23 16:25:12
@misc{1982072,
  abstract     = {Computational modeling is a commonly used method to understand, predict and explain for instance the organization of neuronal connectivity. Here it is applied to the problem of the development of the neural control of locomotion. Locomotion, e.g. walking and swimming, can be characterized as an alternate activation of opposing muscles and is controlled by central pattern generators, CPGs, in the spinal cord that function as relay centers for ascending and descending information. At the onset of development, rhythmic bursts of movements can be seen in the embryo of many species, humans included. These movements have been thoroughly studied in the chick and are believed to be generated by population dynamics in the chick spinal cord due to a hyperexcited spinal network. However, the developing spinal cord undergoes a transition and already early in development, are embryonic movements generated by a CPG network. This paper shows a possible route to develop a model of the possible embryonic development from a hyperexcited spinal network to a central pattern generator. A first model of this is presented, the double feedback model, which includes a developing spinal network and a joint with opposing muscles, all connected by motoneurons and proprioceptic sensory neurons. The hypothesis presented suggests that two types of feedback are required for the development of a functional CPG network, connections directly from the motoneurons to spinal interneurons, more specifically inhibitory R-interneurons (the avian homolog to Renshaw neurons) and sensory connections from the muscle to the spinal network. The idea that sensory afferents can affect or at least tune the development of the neural circuit has been suggested earlier but results are not conclusive. Experiments that aim at evaluating the behavior of the double feedback model at different phases in the embryonic development of locomotion show that even though no alternate behavior similar to that of a CPG develops, the model is still in many cases able to generate a behavior that could be expected in the early embryonic development of the spinal cord. The double feedback model is thus able to capture some, but not all features of the developing spinal cord and can very well serve as a starting point for further development.},
  author       = {Selbing, Ida},
  keyword      = {central pattern generators,spinal cord,neural networks,developing networks,motor control},
  language     = {eng},
  note         = {Student Paper},
  title        = {The Double Feedback Model of Neural Control of Locomotion: Is Immature Behavior Needed to Develop Mature Behavior?},
  year         = {2011},
}