Representing the Marvels of the World with Spatial and Propositional Imagery. A guest post by Nicholas Imlach

Spatial representation uses an image, or part of an image, to explain where something specifically is (see photo). Propositional representations, on the other hand, use symbols or statements to explain where something is (e.g. cat under table).  Although most textbooks will talk about these two types of representation as a debate or a great divide in mental imagery research, I could not help but use the two types of representation in conjunction. While going over mental imagery in last week’s class, I could not help but use propositional information to paint a more vivid representation of a concept that one would normally think of spatially.

While in class I thought about different well-known landmarks such as the Grand Canyon and Niagara Falls, and thought of the implications of both spatial and propositional representations when describing these landmarks to someone. As opposed to driving up and seeing the grandiose size of the objects in your visual field, how could I describe such wonders in words. I’m sure most people, at one time or another, have seen a picture of the Grand Canyon or Niagara Falls and have thought about (if they had not been there before) the true scale of these marvels . By invoking propositional information, such as the specific dimensions of the natural phenomenon in relation to more familiar objects, someone may be able to generate a clearer spatial image when describing such important monuments.

To clarify the old adage “a picture is worth a thousand words,” unless there is previous or given knowledge available to the person looking at the photograph, there is nothing to assist them in scaling the object. One can look at a picture of Niagara Falls and say it is a big waterfall, but how big is “big?” Someone looking at a picture without a scale or relative comparisons could make a judgment or attempt to guess how big. However,  using some additional information, they may be able to form a representation that is more vivid and precise. While looking at the picture, the person showing it to them tells them what the tour guide told them: The Canadian “Horseshoe” part of the falls, for example, is 167 feet high, 2,600 feet around, and roughly 600,000 gallons water go over the falls per second.

Now, looking at the picture above, one may be able to infer how big this part of Niagara Falls actually is, but could they really grasp the enormity without the propositional information? I do not think they could. I do believe with the combination of the spatial (image) and the propositional (verbal/written description), they may be able to. Say the person looking at the picture lives in a 15-story apartment building on the 15^th floor, which is about 150-160 feet high. Maybe that person is also an avid runner and knows that 2,600 feet is about half a mile and knows a specific part of their run which equals half a mile. Now with the propositional representation in conjunction with the spatial one, the person is beginning to create a vivid representation of the concept “Niagara Falls.” The person could say, for example: “If I stood on the roof of my apartment building and looked out, the Falls would be to the pavement below and would stretch to the restaurant down the street. That is a long distance.” I believe the only way to make an accurate spatial representation is by using propositional information as a guide.