sensation and perception

Dr. Swift

Seventh Assignment (Object)

For this assignment, you will have to attach all images that you used, all in the same document.

1. Note that the following diagram may be seen as rows or columns depending on the relative spacing.

Here I clearly see columns. . The vertical center-to-center spacing is about 10 mm, and the horizontal is also about 10 mm, so proximity does not favor either orientation, and what we see is governed by similarity alone.

I would then complete the following table as follows, concluding that the critical ratio in which proximity can no longer outweigh similarity is somewhere between 1.25 and 1.42:

a. Do your own version of the above, using different spacings, and a different variation (e.g. different shapes than I did, or use the same shapes and have the similarity be based on using two different colors, etc. Note that here, the alternating columns should vary on just shape or just color, but not both. I have created a PowerPoint slide available in the Files (ProximityVsSimilarity.ppt) that you can use to create your own forms by editing the shapes and/or colors and then cutting and pasting. You should attach the PowerPoint slides that you create to your assignment. Or, if you would rather use your own tools or do it by hand, that is fine also—just attach it, by scanning it in or by taking a photo. Complete the table and determine the critical ratio, making sure that you list the rows in your table in descending order of ratio of spacing, as I did above.

Critical Ratio ______________________________

b. Now do the same thing, but have the alternating columns vary as to both shape and color. Again, you should attach the PowerPoint slides that you create to your assignment. Or, if you would rather use your own tools or do it by hand, that is fine also.

Critical Ratio ______________________________

c. Summarize your findings in terms of how much spacing difference (in terms of critical ratio) that is needed to offset similarities of form or color—vs. form and color both. Can you make any generalizations about which condition requires a greater ratio? Why do you think that is? (If possible, cut and paste your slides into your Word document, so that you are only attaching a single document.)

2. Find an image on the Web that shows Figure Ground Reversal. Don’t simply find the first one that Google comes up with, but spend a little time searching for a particularly intriguing one. Say why you find it intriguing. Cut and paste it into your assignment, and also give the URL.

3. Have you ever had a situation in which you misperceived something due to it not being in its typical context? (I give a couple of examples in Lecture, such as waking one morning in our “rustic” vacation cottage, and looking down bleary-eyed without my glasses, and seeing what I thought was a rolled-up pair of socks. When I reached down to pick it up, it ran away—turned out it was a fair-sized rat. If you have no such stories to report on yourself, ask a few people until you come up with one.

4. (small amount of extra credit) Try to find, or better yet create, an image analogous to the paper towel roll shown in the PowerPoint slides for the Introductory lecture that slows down the perceptual process. In other words, it should be an image of an every-day object that is shown from an unusual angle, or cropped, etc. so that it is difficult to “get” at first. Cut and paste it into your assignment that you turn in. You should say what it is on a separate page, so that I can look at it first without knowing what it is.