This Weird Optical Illusion Can F*ck With Your Brain For Months


(Not the illusion, but still pretty freaky)

This amazing optical illusion can make you see colours that aren’t really there, but be warned it could ruin your brain for hours.

The McCollough Effect – named after the American psychologist who discovered it – is probably best known as the reason why that ridiculous white/blue dress went viral last year, but it also has another interesting effect.


Want to see the effect in action? Well it’s simple enough, all you have to do is stare at a grid of red and green lines then stare at a similar image in black and white, and you can trick your brain into seeing red as green and green as red.

Amazingly, or alarmingly, this effect is so powerful that researchers have discovered that just 15 minutes of ‘induction’ can have an effect lasting 3.5 months.

To try it for yourself stare at this for 5 minutes (No longer)…

induction2Now what colours do you see here?


In the final image horizontal lines should now appear pinkish and vertical lines a bit green, kind of like they’ve been washed in a weak water colour.

Bizarrely though, scientists don’t really understand what causes the optical illusion and researchers are split three ways on the illusion.

The first theory is that staring at the coloured images causes the visual cortex in your brain to see colour next to particular straight edges.

human brain on white backgroundFlickr

Meanwhile another theory is that your brain is correcting what it thinks is an error after staring at the black and white image for so long, and compensates by adding colour where there is none.

The final theory is that the after image may be related to ‘withdrawal symptoms’ from staring at the colours with the brain now associating the vertical lines with green, and the horizontal lines as red.

All we know is it’s pretty cool…