Abstract
Masked priming effects are taken as evidence that behavior can be influenced by information that does not reach our phenomenal awareness and hence serves as a dissociation between perception and awareness. Priming with unseen stimuli in studies using metacontrast masking procedure are well established, while priming in object-substitution masking (OSM), an alternate masking paradigm, are less well established. Metacontrast and OSM paradigms both significantly reduce visibility of stimuli. However, the former suppresses stimuli even under conditions of focused attention while the latter requires stimulus location uncertainty and distributed attention for masking to occur. Given that attention modulates masked priming effects, we predicted that masked priming should be more robust in metacontrast than OSM paradigms, and that priming in metacontrast should be reduced in distributed attention conditions. Consistent with previous studies we found significant priming with detected primes in both metacontrast and OSM paradigms. Under traditional focused attention conditions (when prime and probe were the only stimuli in the display) we obtained priming with undetected stimuli in a metacontrast paradigm. However, under conditions of distributed attention (when additional task-irrelevant lures were presented in the display) priming with undetected stimuli disappeared. Further, we found no evidence of priming with undetected stimuli in OSM, where distributed attention is required for suppression of stimulus visibility in the first place. Together, these results indicate that nonconscious priming of shape requires some degree of focused attention.
Meeting abstract presented at VSS 2014