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During a discussion with my officemate I told him that I read somewhere that the gas pillar in Carina nebula looks like a cat punching the dog; ever since then, every time my wallpaper slideshow switches to this wallpaper, "cat vs dog" is the first thing that comes to my mind. We were curious whether there is some dedicated terminology for this.

I learned via Google that this is a meme called "What has been seen cannot be unseen", I wonder what is the term for this phenomenon in cognitive science? Like a memory bias during the perception of something? Or it is that people tend to visualize some new concept/picture/term as something they are more familiar with subconsciously?

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up vote 10 down vote accepted

The most relevant term would be Ironic Processing.

Ironic processing is the psychological process whereby an individual's deliberate attempts to suppress or avoid certain thoughts (thought suppression) render those thoughts more persistent.

This is a result of a failure of Thought Suppression or more generally Motivated Forgetting. It appears Thought Suppression doesn't work well and generally the attempt to not think about X results in a sudden increase of thoughts about X.

Since you have a sudden increase of thoughts about the "suppressed" thought, you're strengthening retrieval of it, and you might even be conditioning that thought with the reason you don't want to remember it.

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How interesting! I've noticed this myself but never knew it was an actual concept. – Josh Gitlin Apr 6 '12 at 20:56
@JoshGitlin there's controversial research on Motivated Forgetting, I'm honestly not sure which cases it's been found to be beneficial or detrimental, but I recall learning that it was detrimental in a course on Human Memory. Now I'm curious though – Ben Brocka Apr 6 '12 at 21:01
i'm not sure this answer really fits the question. OP didn't say anything about deliberately trying to forget. i think this is just a simple case of priming. – Jeff Apr 7 '12 at 12:57
@Jeff the "cannot unsee" meme implies one is trying NOT to see it. Otherwise it would simply be "you remember things". Which isn't a good question OR meme. – Ben Brocka Apr 7 '12 at 17:31

Perhaps "visual one-shot learning" is what you're looking for.

Your question reminded me of images like this


which typically take first-time viewers some time to figure out, but on second viewing the subject "pops out" immediately, even if considerable time has elapsed.

Here's an even more striking example:


I believe the phenomenon was described in L. Gregory's "The Intelligent Eye" (1970). [1] looks like an interesting paper (it's where I got the term "one-shot-visual learning" from) - though I can't seem to figure out how to access the full text.

[1] Mogi, K., Sekine, T., & Tamori, Y. (2005). Slow and fast processes in visual "one-shot" learning. Perception, 34, 15-16. URL

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can you expand a little bit on your answer to give a quick sketch of what visual one-shot learning is and why its relevant? – Artem Kaznatcheev Apr 7 '12 at 18:19
Spoiler alert: there's a Dalmation in the first picture (middle right side of the image, facing away, nose to the ground) and a cow in the second (head is on the left side, looking at viewer). – Josh Nov 25 '14 at 16:44

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