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bioRxiv · 10.1101/2022.01.31.478537

Generating spatiotemporal patterns of linearly polarised light at high frame rates for insect vision research

Supple, J. A.·Varennes-Phillit, L.·Gajjar-Reid, D.·Cerkvenik, U.·Belusic, G.·Krapp, H. G.
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Abstract

Polarisation vision is commonplace among invertebrates; however, most experiments focus on determining behavioural and/or neurophysiological responses to static polarised light sources rather than moving patterns of polarised light. To this end, we designed a polarisation stimulation device based on superimposing polarised and non-polarised images from two projectors, which can display moving patterns at frame rates exceeding invertebrate flicker fusion frequencies. A linear polariser fitted to one projector enables moving patterns of polarised light to be displayed, whilst the other projector contributes arbitrary intensities of non-polarised light to yield moving patterns with a defined polarisation and intensity contrast. To test the device, we measured receptive fields of polarisation sensitive Argynnis paphia butterfly photoreceptors for both non-polarised and polarised light. We then measured local motion sensitivities of the optic flow-sensitive lobula plate tangential cell H1 in Calliphora vicina blowflies under both polarised and non-polarised light, finding no polarisation sensitivity in this neuron.

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Supple, J. A., Varennes-Phillit, L., Gajjar-Reid, D., Cerkvenik, U., Belusic, G., Krapp, H. G.. 2022-02-02. Generating spatiotemporal patterns of linearly polarised light at high frame rates for insect vision research. https://doi.org/10.1101/2022.01.31.478537

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