Here’s another one of those head snatchers that will probably drive some of you nuts.

Remember the spooky ghost selfie that had the internet freaking out? Well, forget that one we’ve got a new optical illusion that’s completely befuddled the internet. Marc Blank-Settle stumbled upon a mind-bending occurrence when organizing his toddler’s wooden train tracks. When stacking the two pieces of track on top of each other, he discovered that they look exactly the same in terms of size and length. However, when he placed them next to each other, they totally look different with one being significantly longer.

Sharing his perplexing discovery on Twitter, Blank-Settle wrote; “My toddler’s train track is freaking me out. What’s going on here?” The tweet has since been shared more than a thousand times. Many people expressed their bewilderment, but were unable to correctly explain the reason(s) behind this unusual illusion.

Fortunately, an explanation has been found. It involves a classic Jastrow illusion as unearthed by Joseph Jastrow, an American psychologist in the 19th century, whoo revealed that curved objects appear to be of different sizes since the short edge of the upper object is being compared to the longer edge of the lower one, even though they’re actually of the same size.

Makes sense? Us neither … but its still fun to look at..