The following moving image of a spinning dancer (created by Nobuyuki Kayahara) is one example:
Is the dancer spinning clockwise or counterclockwise? There are no visual clues to distinguish, so your brain makes an assumption, and you can't make it switch. The Rubin vase is another example.
I am reminded of that when I think of one of the best known plagiarism suits in the music world. It involved George Harrison, whose song, "My Sweet Lord" was said to be too similar to the Chiffons's "He's So Fine." Following are the two songs:
The court decided that Harrison had subconsciously copied the Chiffons song,and ultimately he was orderd to pay nearly $600,000. You can read about it here.
What's interesting for me is that, for years I didn't hear the similarity. It didn't matter how many times people pointed it out, or how they explained it. Then, at some point it hit me. As if a window shade had suddenly been drawn back, I saw it. Now, as much as I try, I can't hear either song without thinking of the other. As an aside, I'll note that the above Wikipedia link for Harrison's song gives a music theoretic explanation of the similarities:
Both songs have a three-syllable title refrain ("My Sweet Lord" and "He's so fine") followed by a 5-3-2 descent of the major scale in the tonic key (E major for "My Sweet Lord" and G major for "He's So Fine"). Respective tempos are similar: 121 and 145 bpm. In the respective B sections ("I really want to see you" and "I dunno how I'm gonna do it") there is a similar ascent through 5-6-8, but the Chiffons distinctively retain the G tonic for four bars and, on the repeat of the motif, uniquely go to an A note 9th embellishment over the first syllable of "gonna". Harrison, on the other hand, introduces the more complex harmony of a relative minor (C#m) as well as the oft-repeated, fundamental and distinctly original slide guitar motif.
For all it's worth, I prefer "He's so Fine."