Distinct task-independent visual thresholds for egocentric and allocentric information pick up

The dominant view of the ventral and dorsal visual systems is that they subserve perception and action. De Wit, Van der Kamp, and Masters (2011) suggested that a more fundamental distinction might exist between the nature of information exploited by the systems. The present study distinguished between these accounts by asking participants to perform delayed matching (perception), pointing (action) and perceptual judgment responses to masked Müller–Lyer stimuli of varying length. Matching and pointing responses of participants who could not perceptually judge stimulus length at brief durations remained sensitive to veridical stimulus length (egocentric information), but not the illusion (allocentric, context-dependent information), which was effective at long durations. Distinct thresholds for egocentric and allocentric information pick up were thus evident irrespective of whether perception (matching) or action (pointing) responses were required. It was concluded that the dorsal and ventral systems may be delineated fundamentally by fast egocentric- and slower allocentric information pick up, respectively.

► Subjects were exposed to masked Müller–Lyer stimuli in an action and perception task.
► Both tasks allowed for potential pick up of egocentric and allocentric information.
► Sensitivity to egocentric but not allocentric information under complete masking was evident regardless of task.
► Dissociated task-independent thresholds exist for egocentric and allocentric information pick up.
► Information-based distinction between the dorsal and ventral systems may be more fundamental than distinction based on task.