Scientific American has some interesting information for visual rhetoric.
[R]esearchers found that an attractive image is not more likely to be recognized. Rather “memÂorability seems more related to strangeness, funniness or interestingness,†says Phillip Isola, a graduate student at the Massachusetts Institute of Technology and a lead researcher on the study.
Having people in the picture—even if they are strangers—also help make a photo more memorable, as does the impliÂcation of movement, such as a person running or waves crashing. Human-scale objects—chairs and cars rather than valleys and planets—similarly plant themselves in our mind.
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Still, scenes that lack these attributes are not doomed to be forgotten. Simple changes can increase their memÂorability, such as the presence of a tiny hiker in the backÂground of a mountainous panorama. So the next time you’re out to take a memorable shot, make it interesting—not just pretty.
Very useful information for my students, I think. I will have to look up the study, if the conference proceedings are available. It was “presented at the IEEE Conference on Computer Vision and Pattern Recognition in June.”