Quentin Chi

In what sense are we aware of objects behind the head? Do we experience such objects perceptually, or are they merely remembered, imagined, kinesthetically sensed, or cognitively believed? How is the space behind us represented more generally, and which mental capacities underwrite our experience of the world behind the head? This paper argues that standard models of such experience are insufficient. It develops and defends a novel account according to which the world behind the head is represented by two semi-independent memory systems: a spatial updating system primarily attuned to transportable objects like keys, cups, phones, and other agents, and a cognitive mapping system primarily attuned to non-transportable objects like buildings, walls, and furniture. Each system has a distinct mechanistic and neural basis, and makes a distinct phenomenal contribution to experience. I show how this account intersects with debates about the relationship between perception, imagination, and memory, and supports a view on which rear space experience is a form of present-tensed, memory-constituted perceptual experience.

Humans whose corpus callosum has been surgically severed – “split-brain” humans – have received the lion’s share of attention in unity of consciousness research. Two dominant views have emerged: one-stream views according to which split-brain consciousness is wholly unified, and two-streams views according to which split-brain consciousness is wholly disunified. A third option involving violations of the transitivity of co-consciousness, the partially unified stream view, has seemed to theorists conceptually problematic and empirically unsettled. This paper offers a new argument for the partially unified stream view based on a different population of humans whose corpus callosum never developed in the first place – congenitally acallosal humans. It proposes a “fine-grained” account of the structure of acallosal consciousness on which highly determinate contents, but not broad psychological capacities, are disunified.