Until now, I have never really paid much attention to topics such as change blindness or inattentional blindness. Honestly, they did not seem significant or crucial in visual perception. Nevertheless, my attitude toward these topics quickly changed after I watched the movie clips posted online. The second movie clip (grass field with a barn) especially surprised me because I could not find any conspicuous change even after watching it five times. I finally discovered what was different only after I compared the last scene with the beginning scene separately. The grass getting cut near the right side of the screen was the change being made to the scene. It was then I realized that change blindness could affect our lives greatly. (I will only discuss change blindness in this journal entry.) To determine the cause of change blindness, I turned to Daniel J. Simon’s article. Simon describes change blindness as an “inability to spot changes as observers fail to detect substantial changes to the visual details of objects and scenes.” He lays out several possible explanations for change blindness. The first one is “overwriting.” “The initial representation is simply overwritten or replaced by the blank interval or by the subsequent image.” To me, this explanation seemed most plausible because it is most intuitive. The image of the first scene remains as a simple abstract while the new scene replaces the old image. This new image is understood as the initial image that I first saw. The second one is “first impression.” The observer does not see the final image but is only be able to obtain the initial image. I did not particularly agree with this one because I tend to put more emphasis on the last scene or image. Therefore, it is more likely that I would understand the last impression as the one that remained intact throughout the movie clip or the situation. The third one is that “nothing is stored.” It argues that simply nothing in the visual world is stored internally that an observer does not store anything that goes on in the movie clip. This hypothesis was the one that I had the most trouble understanding because after watching the movie clip, I could recall most of the details of the image. The fourth one is that “everything is stored but nothing is compared.” This one clearly contradicts the third explanation that everything is stored. However, it contains one unique detail. Both the details of the initial image and the details of the final image are stored internally but they are not compared. Therefore, the observer cannot find the differences between the initial and the final images. The final explanation is “feature combination.” The details of the initial image and that of the final image are combined within the observer’s brain so that he or she fails to come up with a conclusion that the image has changed during a certain period of time. These explanations account for part of why change blindness occurs but they cannot be accounted for everything. Few explanations seem farfetched. The overwriting explanation seemed the best one out of the five. I have experienced this change blindness when I was driving. Waiting at the intersection for the traffic light to change, I was looking at a Porche on the other side of the lane. Soon, the light turned green, but I could not see the change. It was not until the cars behind me honked loudly that I realized that the light had changed. The change blindness is occurring in everyday life and it is not something that could be overlooked.References:
http://schneider.lrdc.pitt.edu/P2465/Readings/simons_viscog.pdf
Perception textbook
