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Look at this drawing: What do you see first? The answer to this optical illusion reveals a lot about you...
What can you see: a rabbit? Or a duck?
Psychologists claim the answer you give to this classic optical illusion says a lot about your brain and how it works.
More than a 100 years after it was first sketched, a drawing has sparked huge reaction when recently shared on social media.
Some see a rabbit and others will see a duck - but are you able to see both alternatively?
What you see (and how fast you see it) can indicate how quickly your brain works and how creative you are.
The duck-rabbit drawing was first used by American psychologist Joseph Jastrow in 1899 to make the point that perception is not only what one sees but also a mental activity.
Mr Jastrow's research was based on how quickly one can see the second animal and how fast participants could change their perception of the drawing to switch between the two animals.
The faster you can do this this, the quicker your brain works and the more creative you are, the research suggested.
Well, what do you see?