Below are links to seven sample demonstrations of 16 items with a 600 ms mask.
Three file formats are available for viewing:
After
selecting a demonstration, fixate on the cross. Sixteen shapes will
appear briefly (squares, circles, triangles, and diamonds). One of
them is surrounded by four dots. Your task is to identify the shape
within the four dots. AVI
files (Windows) are of a higher quality with greater temporal precision;
however, AVI files take longer to download because of their size.
Selecting a demo should automatically launch your browser's media
player. Ensure that the media player is not set to loop the movie.
QuickTime
movies are viewable on either Mac or Windows platforms. You must have
the QuickTime player to view them. Download
Quicktime.
Most people see only the four dots and not the shape contained within them. This occurs because the distractor elements prevent attention from being quickly deployed to the target location. The persistence of the four-dot mask at that location leads to a mismatch between the initial unattended representation of the target and the subsequently-attended representation of the mask alone.