Sensation and inferences in perception, metacognition and action

ongoing

The perceptual experience of humans is seamless, although there are major spatial gaps in the available sensory information due to internal (e.g. absence of photoreceptors in the blind-spot) or external reasons (e.g. occlusion by other objects). While the contents of these sensory gaps seem to be completed by inferences, it is unknown how those inferences are dealt with in further processing compared to veridical sensory information. Recently, we and others showed that inferred information is preferred over sensory information in metacognition. This contradicts one of the axioms of current thinking about human information processing, according to which information is weighted by its reliability. SENCES aims to investigate the processing and usage of inferred information in comparison to veridical sensory information. First, we will use psychophysical and behavioral experiments to understand the role of inferences in perception, metacognition and action. Second, we will use EEG to distinguish between different models concerning the neural processing of inferences. Third, we will assess the role of inferences in pathological retinal scotomata and their plasticity along three time scales: across the lifespan by comparing healthy observers and patients experienced with missing sensory information due to long-term visual disorders; in the mid-term by studying the progression of pathological retinal scotomata in patients; in the short-term by training healthy observers with artificially missing sensory information. SENCES will provide crucial insights into how a seamless perceptual experience is constructed and how it is shielded from gaps in sensory information. Studying different phenomena of perceptual completion will allow for the discovery of general principles. Finally, it will uncover positive and negative consequences of perceptual completion in pathological scotomata and might point towards new approaches for early diagnosis and behavioral treatment.