Week 5. What are the phenomenological differences between AB and the masking?
– Masking is masking and AB is AB –
Hunjae Lee (VCC Lab)
Although ‘attention’ can be suggested as a crucial factor of both attentional blink (AB) and the masking (Enns et al, 2000), they look still different at a glance. It may imply that they are quite different in phenomenon. And it comes from that masking has more diversity than AB in general, such as various time lines (eg. backward or forward masking), spatial relationships (eg. overlapping or non-overlapping), in contrast, AB focuses more on temporal resolution of attention.
But even about critical time interval between T1 & T2 in AB (200~400 ms) and para-contrast & masking (100~150 ms) shows different characteristic of two methods. (Ogmen et al., 2003). The fact can suggest that AB involve somewhat higher level of processing compared to masking. And one possible explanation of this difference is that attention in AB has a kind of effect on just selecting stimuli rather than processing it. But in masking attention plays a role in active early level of processing, like integrating basic features. (Thanks to Yihwa for this idea.) In order to test this hypothesis, suppose a question like this, “Do priming effect or unconscious processing of AB and masking have differences?” We still need more evidences that show differences in effect size or in quality, because it seems that effects also appear in masking (Bar et al, 1998; Lau et al, 2006).
Going back to the starting point, when you take part in experiments the most remarkable difference in subjective experience between two methods is the bad feeling of T2 omission in AB. In masking, it is natural that masking blocks the target. Despite of the argument that the object substitution is the mechanism accounts for masking in the AB (Enns et al, 2000), backward masking of the second target is still masking not the AB.
Enns, J. T., & DiLollo, V. (2000). What’s new in visual masking. Trends in Cognitive Sciences, 4, 345-352.
Breitmeyer et al. (2004). A comparison of masking by visual and transcranial magnetic stimulation: implications for the study of conscious and unconscious visual processing. Consciousness and Cognition, 13, 829-843.
Ogmen, H. et al. (2003). The what and where in visual masking. Vision Research, 43, 1337-1350.
Bar, M., & Biederman, I. (1998). Subliminal visual priming. Psychological Science, 9, 464-469.
Lau, H. C. and R. E. Passingham (2006). Relative blindsight in normal observers and the neural correlate of visual consciousness. Proceedings of the National Academy of Sciences of the United States of America, 103(49), 18763-8.