Sensitivity to motion and higher-order visual processing in nocturnal and diurnal hawk moths

Abstract

Event Abstract Back to Event Sensitivity to motion and higher-order visual processing in nocturnal and diurnal hawk moths Anna L. Stöckl1*, David O'Carroll2 and Eric Warrant1 1 Lund University, Biology, Sweden 2 The University of Adelaide, School of Medical Sciences, Australia Even though humans see poorly at night, the majority of the world’s animals – both on land and under water – are active in dim light and many of them have excellent vision. Despite possessing tiny eyes and brains, nocturnal insects can distinguish colour, avoid obstacles during flight and find their way home using learned visual landmarks. But how is this remarkable visual performance possible? How have the properties of the visual circuitry been optimised to maximize visual performance in dim light conditions? In order to approach these questions, we are studying the visual motion processing circuitry in hovering hawkmoths – a group of fast-flying insects renowned for their impressive visual abilities, in which closely related species are active under completely different light conditions, ranging from bright sunlight to starlight. One way of increasing visual performance in dim light is to spatially sum signals from neighbouring visual channels. In the first optic neuropil of insects, the lamina, the monopolar cells of nocturnal species possess an anatomy that makes them well suited to the summation of visual signals: their lateral processes are long and extend to neighbouring cartridges. Using the Golgi staining method, we compared the lengths of these lateral processes between the day-active hawkmoth Macroglossum stellaratum and the night-active Deilephila elpenor. As predicted for a possible function in spatial summation, the lateral processes of D. elpenor are longer than those of M. stellaratum and could potentially pool information from cartridges further away. Wide-field motion-sensitive neurons in the lobula plate are tuned to the optic flow experienced during flight. We recorded from these neurons to quantify the spatial and temporal response characteristics of the visual system of hawkmoths, to extract the amount of spatial and temporal summation implemented in both nocturnal and diurnal species. Preliminary results from intracellular recordings at day-light intensities show that HS-like neurons in M. stellaratum respond to higher spatial and temporal frequencies than those of D. elpenor, even though both species have comparable optics, which strongly suggests spatial and temporal summation of signals. Further recordings at decreasing light intensities will allow us to determine the general neural strategies that nocturnal species use to optimise visual performance at night, principles that are likely to apply to all nocturnal animals. Keywords: motion vision, Lamina, nocturnal vision, Lobula plate, hawkmoths, spatial summation Conference: International Conference on Invertebrate Vision, Fjälkinge, Sweden, 1 Aug - 8 Aug, 2013. Presentation Type: Poster presentation preferred Topic: Motion vision Citation: Stöckl AL, O'Carroll D and Warrant E (2019). Sensitivity to motion and higher-order visual processing in nocturnal and diurnal hawk moths. Front. Physiol. Conference Abstract: International Conference on Invertebrate Vision. doi: 10.3389/conf.fphys.2013.25.00112 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Feb 2013; Published Online: 09 Dec 2019. * Correspondence: Ms. Anna L Stöckl, Lund University, Biology, Lund, 223 62, Sweden, anna.stoeckl@uni-konstanz.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Anna L Stöckl David O'Carroll Eric Warrant Google Anna L Stöckl David O'Carroll Eric Warrant Google Scholar Anna L Stöckl David O'Carroll Eric Warrant PubMed Anna L Stöckl David O'Carroll Eric Warrant Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.