In Metacontrast masking, does the target or mask appear first?

In Metacontrast masking, the target appears first, followed shortly by the mask. This phenomenon involves a unique temporal arrangement of visual stimuli where the target is an initially visible stimulus, and the mask is a subsequent stimulus that appears nearby but is distinctly separated in time.

The primary reason that this arrangement is effective in creating a masking effect is that the mask inhibits the perception of the target even after the target is no longer visible. This interaction relies on the neural processing of the visual system; when the target is presented first, it activates certain neural pathways that the immediate subsequent presentation of the mask can disrupt.

The timing and spatial arrangement of these two stimuli are crucial; the target needs to be perceived first to allow the masking effect to take place. Hence, understanding the sequence helps in grasping how visual perception and processing can be influenced by sequential stimuli in this specific masking scenario.