The effect of flanker category on crowding is modulated by processing time

When the human visual system processes complex scenes, crowding is considered a bottleneck in interpreting visual information. Several studies have reported that visual crowding seems to occur in the early stage of visual possessing. After that, extensive evidence suggested that high-level visual information has a major effect on crowding, which showed substantial interest in the impact of high-level visual information on crowding. However, the temporal property of high-level crowding is not well understood. Here, we performed a series of behavioural experiments to show how flanker category information and exposure time affected crowding's intensity. We found that as the category's effect becomes stronger, the intensity of crowding will be reduced in longer exposure time. The peak of this effect occurs at the time window of 100 ms-150 ms after the stimulus appears. We propose that exposure time may modulate high-level information processing depth, which can adjust multi-level crowding.