Abstract
Identifying how neural networks communicate through the organization of microcircuits in the central nervous system is a long-standing challenge in neuroscience. Collecting this information in areas that lack clear cellular organization such as the dorsal horn of the spinal cord, where heterogeneous populations of cells are intermingled, has been especially difficult. Improvements in optical technologies in combination with advanced genetic techniques, collectively termed optogenetics, have greatly improved our ability to address this issue. Several studies have now employed optogenetics to study the connectivity of various dorsal horn interneuron populations, as well as modality-specific input provided by primary afferent populations. This work allows for a circuit-based understanding of spinal sensory processing mechanisms to be assembled, something that has been sought since the publication of the gate control theory in 1965. This chapter seeks to provide a practical, experimental-based description of the various optogenetic approaches available to characterize dorsal horn circuits at a level of resolution not possible using more classical approaches.
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Smith, K.M., Graham, B.A. (2022). Channelrhodopsin-2 Assisted Circuit Mapping in the Spinal Cord Dorsal Horn. In: Seal, R.P. (eds) Contemporary Approaches to the Study of Pain. Neuromethods, vol 178. Humana, New York, NY. https://doi.org/10.1007/978-1-0716-2039-7_18
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DOI: https://doi.org/10.1007/978-1-0716-2039-7_18
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