Competition for consciousness among visual events: The psychophysics of reentrant visual processes.

TLDR

Reentrant signaling is the main inter‑area communication in the brain, and masking experiments based on this principle challenge feed‑forward theories. Masking arises when a brief target‑plus‑mask display is followed by mask alone, producing an object‑substitution effect when reentrant representations mismatch lower‑level activity, and this iterative reentrant processing is captured by a computational model that fits the data well. The study identified an early, luminance‑sensitive masking process and a later, attention‑dependent object‑substitution process, and the computational model accounts for all visual masking phenomena better than traditional feed‑forward theories.

Abstract

Advances in neuroscience implicate reentrant signaling as the predominant form of communication between brain areas. This principle was used in a series of masking experiments that defy explanation by feed-forward theories. The masking occurs when a brief display of target plus mask is continued with the mask alone. Two masking processes were found: an early process affected by physical factors such as adapting luminance and a later process affected by attentional factors such as set size. This later process is called masking by object substitution, because it occurs whenever there is a mismatch between the reentrant visual representation and the ongoing lower level activity. Iterative reentrant processing was formalized in a computational model that provides an excellent fit to the data. The model provides a more comprehensive account of all forms of visual masking than do the long-held feed-forward views based on inhibitory contour interactions.