The head direction circuit of two insect species
Abstract
Recent studies of the Central Complex in the brain of the fruit fly have identified neurons with activity that tracks the animal's heading direction. These neurons are part of a neuronal circuit with dynamics resembling those of a ring attractor. The homologous circuit in other insects has similar topographic structure but with significant structural and connectivity differences. We model the connectivity patterns of two insect species to investigate the effect of these differences on the dynamics of the circuit. We illustrate that the circuit found in locusts can also operate as a ring attractor but differences in the inhibition pattern enable the fruit fly circuit to respond faster to heading changes while additional recurrent connections render the locust circuit more tolerant to noise. Our findings demonstrate that subtle differences in neuronal projection patterns can have a significant effect on circuit performance and illustrate the need for a comparative approach in neuroscience.
Data availability
All source scripts for producing the data as well as for generatingFigures 6A, 6B, 7, 8, 9, 10, 11, 12, 14 and Tables 1 and 2 are located at https://github.com/johnpi/eLife_Pisokas_Heinze_Webb_2019
Article and author information
Author details
Funding
H2020 European Research Council (Grant agreement no. 714599)
- Stanley Heinze
University Of Edinburgh (Graduate Student Fellowship)
- Ioannis Pisokas
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Pisokas et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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