A novel texture backward masking method to locate critical recurrent processes in human vision

Mounting evidence suggests that recurrent processes in the visual system play a critical role during challenging recognition tasks. Backward masking techniques have traditionally been used as a non-invasive method for studying recurrent processes: A mask follows the target image, presumably disrupting ongoing processes. However, these techniques have the limitation that they do not allow the identification of the stage of the visual system at which critical recurrent processes are taking place. Here, leveraging advances in texture synthesis via deep networks, and the approximate correspondence between stages of the visual system and layers of deep networks, we develop a novel psychophysics paradigm where masks with textures targeting different stages of the visual system follow the presentation of challenging images. In a series of experiments, we present objects to human subjects either for a short duration or in unusual poses, followed by a textured mask either designed to only target the early visual system, or the entire visual system. We find that both texture types equally affect recognition abilities, suggesting that recurrent processes in or towards early stages of the visual system are already recruited for these recognition tasks.