If you look at the black-and-white grid again, you should notice a green haze around the horizontal lines, and a magenta haze around the vertical lines. The intensity of this effect varies between individuals. If you don’t see this, go gaze at the colored grids for a while longer.
The effect typically lasts for hours, or even overnight. The duration can be changed by the consumption of coffee and other psychoactive drugs. One paper found that it is stronger in extroverts than introverts, and might be a reliable test for extroversion.
You’re welcome.
I don’t see squat.
I tried again. Probably doesn’t work because I’m colourblind.
Works for me, that’s awesome. It took almost 5 mins of staring though, and I only saw the magenta after looking away for a few minutes.