Optical illusion: Stare at this cross for a few seconds, and what happens next will surprise you!

This type of illusion is called the The Troxler Effect, and was developed by physician Ignaz Paul Vital Troxler in 1804. It reveals that everything exists in reality, although our perception makes things seem to disappear. Your brain detects that neurons in your visual system have stopped firing steadily in response to the steady, unfocused light from the blurred edges