04/02/2012 by Josephine Rose
Warning: If you think you are the type who has a view on Life and magical things that can be easily ruined by scientific explanations, then turn back, and visit us again on our next post
If however, you are the type who’d be more amazed by something by knowing how it works, then read on…
One night, my Papa called me over to the living room and showed me an email that he got. It was one of those optical illusions, and he wanted to know if I knew how it worked. He was pretty amazed by it.
In the email, there was an image of this lady in black and white, and you were to stare at the coloured dots on her nose for around 30 seconds, then look at the empty white space beside her:
Now, hopefully you saw what amazes everyone when they encounter an optical trick like this, or similar others. This has been appearing on Facebook for quite some time too, and even though I’ve been tempted to explain how it works (at the risk of sounding nerdy on a social website), I decided to blog about it here.
This is what I told my dad. Think of our vision system as having special cells which are able to process color. The cells are grouped in a way that certain colors oppose each other. It’s sort of like a see-saw mechanism, where only one-colour can stay down (or be seen), while the other colour remains up (and unseen).
This is known as the Opponent Processing Theory of colour vision, proposed by Ewald Hering, and the opposing colours are: Red vs. Green, Blue vs. Yellow, and Black vs. White.
The theory goes to state that when the cells in your eyes for example, keep seeing the colour Green only, you’d eventually exhaust those ‘Green’ cells, so when you look away, you’d see an excess of Red (the opposite colour that you’ve been trying to hold back when you were seeing Green).
In short, starring at the black and white lady for 30 seconds exhausts all the ‘black’ and ‘white’ cells, resulting in…
Well, see for yourself