**A note from Dr. Winawer on the materials used in the present replication:** "The original experiments were coded in C using Vision Shell (from the Harvard Vision Lab), and run on Macs using OS 9 (native, not OS9 simulation). I probably have the original Vision Shell experiments, though I would have to check, and also find an OS-9 machine to check that they look OK and run properly. " "In the years since, some of the experiments were recoded in Matlab using Psychtoolbox. In fact I shared a Matlab version of the published experiment with a grad student at CalTech, Nathan Faivre. He re-ran one the experiments and also tested whether the effects persist in the absence of awareness (continuous flash suppression). He found that the results replicated successfully but did not persist under flash suppression - in the absence of awareness - http://www.visionsciences.org/abstract_detail.php?id=456." "So I probably have the original OS-9 experiments (Vision Shell) and also a Mac OS-X version (Matlab). The Matlab version uses the same images as the OS-9 version but might not be identical in all respects. I would have to take a look and see." **The Matlab version of the study was used in the present replication.**