Arrays of 8, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB)task where there was a 50% chance that one rectangle would change orientation between stimuli. The effects of CB were reduced by cueing the spatial location of the change in either the first stimulus or, importantly, the interval. This supports the idea that a representation of the first stim-
ulus is formed and persists through the interval before being `overwritten' by the second presentation of the stimulus (Landman et al, 2003 Vision Research 43 149 ^ 164). Previously we used eighty-five naive observers to investigate task difficulty using large and small rectangles (Wilson et al,2005 Perception 34 146 ^ 147). Here we used two experienced observers to test if the representation remains robust across longer intervals. Observers showed steady performance across the interval suggesting a robust representation up to an interval of 5000 ms.We consider two possible explanations: (i) a pre-attentional representation may last much longer than previously expected; (ii) observers are using a strategy
