Space is a fundamental dimension of physical and perceptual reality. However, physical space and perceptual space are not the same. Although we experience space as a uniform physical entity around us, the properties of the sensory systems and of our behavior, as well as many visual illusions, clearly show that perceptual space is constructed by the brain and decoupled from its physical counterpart. Recent research has shown that visually perceived space is strongly influenced by eye movements and can thus be understood as part of an action-perception loop that is geared towards appropriate behavior to ensure survival. Past research has mostly considered static conditions, in which a given motor act is performed and its impact on spatial perception is studied. The brain, however, is a learning machine. Outcomes of behavior almost always are used to update internal processes to adapt the system better to its environment. PLATYPUS investigates how visual space is shaped and maintained via adaptive interactions with eye- and arm movements. Research within PLATYPUS will lead to novel insights on the nature of perceptual space and a more complete view of spatial perception. These insights have strong potential for translation into applied fields. On the one hand, adaptive changes to visual perception and motor behavior occur whenever one needs to adjust to the wearing of new glasses, especially when they contain progressive lenses. Since all people develop presbyopia with age, and in about a fourth of the population presbyopia is co-morbid with myopia, this affects a large part of the population in the EU and elsewhere. On the other hand, PLATYPUS insights could potentially enhance the effectiveness and efficiency of applications employing virtual reality, be it in the private (e.g. gaming community) or in the public sector (e.g. health-care industries).
