Generators (CPGs) are being used for controlling the complicated gaits and timing required for stable walking. Traditionally, these models are precisely designed for oscillation at a set of specific frequencies and phase relationships, which while easier to design is not conducive to robust and stable walking. In recent years, work has been done on designing adaptive models of CPGs. These CPGs are able to exhibit complex behaviors such as learning the resonant dynamics of a system to improve walking stability, as well as using mathematical learning rules to learn arbitrary signals and embed their relationships within the system. This work explores the possibility of implementing an adaptive frequency CPG with a similar behavior to these systems, using conductance-based models of dynamic non-spiking neurons connected as a synthetic nervous system (SNS).
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Neuromodulation of central pattern generators and its role in the functional recovery of central pattern generator activity
Neuromodulators play an important role in how the nervous system organizes activity that results in behavior. Disruption of the normal patterns of neuromodulatory release or production is known to be related to the onset of severe pathologies such as Parkinson’s disease, Rett syndrome, Alzheimer’s disease, and affective disorders. Some of these pathologies involve neuronal structures that are called central pattern generators (CPGs), which are involved in the production of rhythmic activities throughout the nervous system. Here I discuss the interplay between CPGs and neuromodulatory activity, with particular emphasis on the potential role of neuromodulators in the recovery of disrupted neuronal activity. I refer to invertebrate and vertebrate model systems and some of the lessons we have learned from research on these systems and propose a few avenues for future research. I make one suggestion that may guide future research in the field: neuromodulators restrict the parameter landscape in which CPG components operate, and the removal of neuromodulators may enable a perturbed CPG in finding a new set of parameter values that can allow it to regain normal function.
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- Award ID(s):
- 1715808
- PAR ID:
- 10197342
- Date Published:
- Journal Name:
- Journal of Neurophysiology
- Volume:
- 122
- Issue:
- 1
- ISSN:
- 0022-3077
- Page Range / eLocation ID:
- 300 to 315
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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