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bioRxiv · 10.1101/2020.12.03.410241

Colourfulness as a possible measure of object proximity in the larval zebrafish brain

Bartel, P.·Janiak, F. K.·Osorio, D.·Baden, T.
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Abstract

The encoding of light increments and decrements by separate On- and Off- systems is a fundamental ingredient of vision, which supports the detection of edges in space and time and makes efficient use of limited dynamic range of visual neurons [1]. Theory predicts that the neural representation of On- and Off-signals should be approximately balanced, including across an animals full visible spectrum. Here we find that larval zebrafish violate this textbook expectation: in the fish brain, UV-stimulation near exclusively gives On-responses, blue/green-stimulation mostly Off- responses, and red-light alone elicits approximately balanced On- and Off-responses (see also [2-4]). We link these findings to zebrafish visual ecology, and suggest that the observed spectral tuning boosts the encoding of object "colourfulness", which correlates with object proximity in their underwater world [5].

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Bartel, P., Janiak, F. K., Osorio, D., Baden, T.. 2020-12-03. Colourfulness as a possible measure of object proximity in the larval zebrafish brain. https://doi.org/10.1101/2020.12.03.410241

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