We as human beings are able to move easily through our surroundings because our brains can rapidly process visual information. Other species also rely on being capable of extracting information from their environment quickly and accurately, even when there are abrupt changes to external inputs – as do state-of-the-art technical devices that employ computer vision. Using the fruit fly Drosophila melanogaster and other insects as examples, neurobiologist Professor Marion Silies of Johannes Gutenberg University Mainz (JGU) is looking at how various visual systems react to specific environments and accommodate their own behavioral repertoires. The European Research Council (ERC) is sponsoring her AdaptiveVision project with EUR 2 million. The ERC Consolidator Grant is one of the most richly endowed EU funding awards and is given to selected top-level researchers. Marion Silies has been Professor of Neurobiology at JGU since 2019 and had already been awarded an ERC Starting Grant in the past.
Visual processing strategies need to react quickly to changes
We rely to a very large extent on our eyes to maneuver through the world. Our eyes operate reliably throughout the whole day, even at dusk, dawn, or when there are sudden changes to light conditions. Our vision is able to adapt to a vast array of different situations, such as when we move from a brightly lit space into the shadow or our gaze follows objects into the shade. While humans and animals easily handle such transitions, rapid fluctuations in luminance represent a major problem for camera-based navigation systems. In view of this, the main objective of the AdaptiveVision project is to understand the corresponding underlying mechanism in animal models.
The environments and behavior of animals influence visual inputs
A moving animal will, due to its own motion, encounter sudden changes in luminance. Certain motion patterns will also be generated on its eyes as the result of the fact that the outside world moves relative to the observer. Some challenges affect all visual systems while others can be specific to the system. Animals, for example, live in different habitats and are thus confronted with diverse visual environments. They also exhibit differing behaviors and their behavior, in turn, influences their visual inputs. In the case of a flying animal, the visual information that has to be processed is more complex than that of a walking animal.
"In this context, we are interested to understand visual processing mechanisms and their adaptation to differing conditions. We will first investigate general principles of visual processing strategies," explained Professor Marion Silies. "Then we want to learn how various visual systems are adapted to specific environmental and behavioral conditions." For this purpose, Silies and her team will be investigating two visual computations: the ability to accurately compute contrast in a dynamically changing setting and the encoding of the global motion patterns generated by self-motion.
To explore these computations, the researchers will first use the fruit fly Drosophila melanogaster as an animal model. They will then employ a comparative approach to uncover how differing visual systems are able to adapt to specific conditions, created by the environment or by the animal's behavior. To achieve this, different Drosophila species will be developed as genetic models, while techniques for the investigation of molecular mechanisms and neuronal circuits will also be employed in other insects, such as hover flies. Silies' team already has considerable expertise in the development of genetic tools.
ERC Consolidator Grant for the AdaptiveVision project directly follows earlier ERC funding
Marion Silies studied biology and obtained her doctorate at the University of Münster studying the development of the nervous system. As a postdoctoral researcher, she worked in Professor Tom Clandinin's lab at Stanford University. Here she mapped and characterized neuronal circuits involved in motion detection and began developing genetic tools. From early 2015, she was a group leader at the European Neuroscience Institute in Göttingen until being appointed Professor of Neurobiology and head of the Neural Circuits Lab at Johannes Gutenberg University Mainz in early 2019. She is a fellow of JGU's Gutenberg Research College (GRC). Silies received an ERC Starting Grant for her "Microcircuitry of the Drosophila visual system" (MicroCyFly) project. The new ERC Consolidator Grant will directly follow the earlier ERC funding.
The ERC Consolidator Grant is one of the most richly endowed EU funding schemes given to individual researchers. The European Research Council uses these grants to support outstanding researchers within seven to twelve years after completing their doctorate. In order to receive the grant, applicants must not only demonstrate excellence in research, but also provide evidence of the groundbreaking nature of their project and its feasibility. The funding period is five years.
https://ncl-idn.biologie.uni-mainz.de/ – Neural Circuits Lab of Professor Marion Silies at the JGU Department of Biology ;
https://www.grc.uni-mainz.de/prof-marion-silies/ – GRC fellow Professor Marion Silies ;
https://erc.europa.eu/news/erc-2021-consolidator-grants-results – ERC press release "313 new ERC Consolidator Grants to tackle big scientific questions"
https://www.uni-mainz.de/presse/aktuell/10771_ENG_HTML.php – press release "Fruit flies respond to rapid changes in the visual environment thanks to luminance-sensitive lamina neurons" (5 Feb. 2020) ;
https://www.magazin.uni-mainz.de/10771_ENG_HTML.php – JGU Magazine: "How flies and humans see the world"