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TY - THES AU - Wiesbrock, Christopher TI - Visual perception of artificial and nature-inspired stimuli in an open-source python-based touchscreen chamber for operant conditioning PB - RWTH Aachen University VL - Dissertation CY - Aachen M1 - RWTH-2021-03163 SP - 1 Online-Ressource : Illustrationen, Diagramme PY - 2020 N1 - Veröffentlicht auf dem Publikationsserver der RWTH Aachen University 2021 N1 - Dissertation, RWTH Aachen University, 2020 AB - The visual system of the mouse is a long-standing component of neuroscientific research. There is an ongoing discussion about how to stimulate the visual system in a meaningful way. Here, stimulation competes with artificial and nature-inspired stimuli. The main difference is the different degree of parameterization of the two stimulus approaches. The more clearly the parameters are defined, the more likely it is that the image statistics will be associated with an experimental result. With the help of so-called motion clouds, a stimulus has been created that is able to reproduce natural image statistics while at the same time providing a high degree of parameterization. In the present thesis the motion clouds will be tested in a behavioral experiment with mice with regard to the influence of individual parameters. First, a test setup was developed based on the principle of operant conditioning. This system, the so-called touchscreen chamber, is a highly automated tool for animal training. At the same time, the modular and flexible hardware and software combination offers the possibility to work with stimuli that can be freely selected. A first test of the experimental setup was carried out by experimentally verifying a test of the effect of over-representation of neurons in the primary visual cortex that respond to horizontal and vertical stimuli. This circumstance is also related to the orientations in natural photographs, which on average show an overrepresentation of these orientations. In this thesis it could be shown that this effect in mice leads to a better discrimination of orientations when they are horizontal or vertical than when they are in between. However, this effect could be eliminated in the experiment by training the animals to distinguish the underrepresented orientations from others. In the next step the experimental concept was applied to the nature-inspired motion clouds. It is assumed that the processing in the cortex is based on parallel connected sensory channels. Here, two experiments are presented in which the animals learn to distinguish between two differently oriented motion clouds, and the differentiation of motion clouds with a different spatial frequency. It can be shown that different bandwidths of the spatial frequency, as it occurs in nature, do not influence the orientation difference. In contrast, a higher bandwidth of orientations in the stimulus leads to an improved discrimination of the spatial frequency. This supports the hypothesis that several activated sensory channels improve experimental performance. Finally, the experiments, in particular the training program and the orientation discrimination for the education of biology students were modified and proved to be a sound educational concept. LB - PUB:(DE-HGF)11 DO - DOI:10.18154/RWTH-2021-03163 UR - https://publications.rwth-aachen.de/record/816407 ER -