Distinctly perceptual possibilities: Amodal completion is disrupted by visual, but not cognitive, load

Across developmental, cognitive, and social psychology, there has been a growing interest in studying when and how people represent mere possibilities---states of the world that have not been realized. Recent research has extended this growing interest to visual paradigms and has argued that people may literally perceive such mere possibilities, e.g., seeing the shape that would be made if two smaller shapes were put together (Guan & Firestone, 2020). An important open question is whether the representation of possibilities observed in these visual paradigms should be understood as a part of a more general system underwriting possibility representations or whether it is best understood as a separate and distinctly perceptual phenomenon. Across three studies, we provide clear evidence for the latter hypothesis. Employing the most widely-studied visual paradigm that involves the perception of possibilities, amodal completion, we demonstrate that the representation of possibilities in this visual task is selectively disrupted by perceptual load but not working-memory load. This provides clear evidence that the key processes underlying the perception of possibilities occur before the information reaches high-level cognition. The representation of such possibilities is distinctly perceptual.