The neural control of insect locomotion is distributed among various body segments. Local pattern-generating circuits at the thoracic ganglia interact with incoming sensory signals and central descending commands from the head ganglia. The evidence from different insect preparations suggests that the subesophageal ganglion (SEG) may play an important role in locomotion-related tasks. In a previous study, we demonstrated that the locust SEG modulates the coupling pattern between segmental leg CPGs in the absence of sensory feedback. Here, we investigated its role in processing and transmitting sensory information to the leg motor centers and mapped the major related neural pathways. Specifically, the intra- and inter-segmental transfer of leg-feedback were studied by simultaneously monitoring motor responses and descending signals from the SEG. Our findings reveal a crucial role of the SEG in the transfer of intersegmental, but not intrasegmental, signals. Additional lesion experiments, in which the intersegmental connectives were cut at different locations, together with double nerve staining, indicated that sensory signals are mainly transferred to the SEG via the connective contralateral to the stimulated leg. We therefore suggest that, similar to data reported for vertebrates, insect leg sensory-motor loops comprise contralateral ascending pathways to the head and ipsilateral descending ones.
|Number of pages||9|
|Journal||Journal of Insect Physiology|
|State||Published - 1 May 2018|
Bibliographical noteFunding Information:
This work was supported by the Young Scholar Fund, University of Konstanz, the Lion foundation for a travel scholarship to JW and also in its final stages by the German Research Council (DFG; Grant RIRI). We thank Prof. Hans-Joachim Pflüger and Prof. Peter Bräunig for productive discussion and support.
This work was supported by the Young Scholar Fund , University of Konstanz , the Lion foundation for a travel scholarship to JW and also in its final stages by the German Research Council ( DFG ; Grant RI RI ). We thank Prof. Hans-Joachim Pflüger and Prof. Peter Bräunig for productive discussion and support.
- Sensory-motor integration
- Subesophageal ganglion