Everybody loves a good optical illusion - they're fun, challenging and a good way to train your brain to be more observational.
Doing them regularly can also help to improve your cognitive abilities, so it's worth challenging yourself every once in a while.
Some are definitely harder than others, and can sometimes take a long time to crack. But generally the quicker you work it out, the better your observational skills are.
To really test out your abilities, try having a go at this optical illusion that challenges you to spot a hidden panda amongst people in the first seven seconds.The Daily Star reports that it's a real "head-scratcher" and has been leaving people stumped.
Read more on dailyrecord.co.uk