Magic of neuroscience

Misdirection-vanishing lighter trick

The "vanishing-lighter illusion," provides further evidence that the magician is manipulating the spectators' attention at a high cognitive level; the direction of their gaze is not critical to the effect. In the vanishing-illusion the magician only pretends to throw the lighter. His head and eyes follow the upward trajectory of an imaginary lighter, but instead of tossing the lighter, he secretly drops it. What most spectators perceive, however, is that the (unthrown) lighter ascends— and then vanishes in midair.

Studies revealed that the spectators' gaze did not point to where they themselves claimed to have seen the lighter vanish. The finding suggested the illusion did not fool the brain systems responsible for the spectators' eye motions. Instead, the magician's head and eye movements were critical to the illusion, because they covertly redirected the spectators' attentional focus (rather than their gaze) to the predicted position of the lighter.

The neurons that responded to the implied motion of the lighter suggested by the magician's head and eye movements are found in the same subvisual areas of the brain as neurons that are sensitive to real motion. If implied and real motion activate similar neural circuits, perhaps it is no wonder that the illusion seems so realistic. Scientists hypothesized that the vanishing lighter may be an example of "representational momentum." The final position of a moving object that disappears is perceived to be farther along its path than its actual final position—as if the predicted position was extrapolated from the motion that had just gone before.