There's more to magic than meets the eye

Our perception of an event is often modulated by our past experience and expectations [1,2]. Here we used a magic trick [3] to demonstrate how magicians can distort our subjective perception and we investigate the mechanisms behind this deception. We found that when a magician performed an illusion in which a ball was seen to vanish in the air, 63% of observers perceived the ball leave his hand, move upwards, and disappear even though the ball did not leave the magician’s hand. Moreover, observers’ illusory perception of the ball was determined by cues that indicated the ball’s location, namely the magician’s head direction, rather than the percept itself. Furthermore, eye movement records revealed participants’ strategic use of social cues prior to looking at the ball. Surprisingly, however, when the ball was not physically present, observers did not look at the area where they claimed to have seen the ball vanish, suggesting that the oculomotor system was not fooled by the illusion. These results show that although people’s subjective percept is determined by expectations, the oculomotor system is largely driven by accurate bottom-up information, which is consistent with the suggestion that there are separate mechanisms for perception and visuomotor control [4]. A striking example of magicians’ deception is the vanishing ball illusion, in which a ball apparently disappears in mid air. This illusion is created by pretending to throw a ball up in the air, when in fact it remains secretly palmed in the magician’s hand [3]. If done convincingly, the observer should perceive the ball as moving up in 2nd real throw Fake throw 1st real throw