Filling-In the blank: perceiving through the lens of prior knowledge.
As soon as we open our eyes, we have the immediate impression of a richly detailed visual world. However, the empirical data on visual capacity suggest that people perceive and remember strikingly little of the world around them. Why people think they are highly skilled in visual perception when the empirical evidence shows that they see so little? One exciting possibility is that our perceptual experiences represent more than the physical visual input, in that they are rather constructed based on prior knowledge. Indeed, particularly when the visual information in input is limited or absent, our memories about the world allow to fill-in the visual scene, thereby generating the visual experience of objects that are subjectively perceived, but objectively not visible. These memory-based percepts may allow to render the rich visual world that people perceive, independently of  capacity-limited sensory processing. In this project I ask how memory-based percepts are instantiated in the brain, and whether they are distinct from memories that do not elicit  the subjective impression of seeing an object. To answer this question, I will make use of a combination of  correlational and causal neurocognitive methods. First, I will characterise the spatiotemporal profile of memory-based object percepts via functional Magnetic Resonance Imaging (fMRI) and Magnetoencephalography (MEG). Then, I will use Transcranial Magnetic Stimulation (TMS) to test whether activity of visual cortex is causally necessary for memory-based percepts to arise. The present studies will elucidate whether visual cortex determines our visual experiences beyond the sensory information in input. In doing so, they speak to the broader question of whether there is a ""joint"" between perception and cognition towards a better understanding of the content of our phenomenological experiences.