Movie #1 (MIB) (MIB.mov: 2757 kbytes)
Instructions. This first movie is a basic demonstration of the motion-induced blindness (MIB) phenomenon. (See our paper for discussion and citations.) Your task is to fixate the central white circles and attend to the yellow disc. Throughout the demonstration, you should try to keep your eyes as still as possible, fixated on the white circles: if you move your eyes, the effect will not work. While you are fixating, you should start to experience MIB: the yellow disc will begin to fluctuate in and out of awareness. In reality, it is never leaving the screen. Practice with this demonstration for a minute until you can reliably get MIB episodes to last for around 2 seconds. (It may help to shut shades and turn off lights.)
Movie #2 (The Disappearing Disc) (disdisc.mov: 4546 kbytes)
Instructions. In this movie you will try to see the disappearance of something you can't see. In our study, we asked the following question: What happens if, during MIB, we physically remove the yellow disc from the screen. Since you can't see it anyway, during MIB, this is essentially a change from nothing to ... nothing. Nevertheless, most observers are able to see the disappearance. The tricky part of demonstrating this in a movie is that the phenomenon is really interactive: in our Macintosh demonstration application, for example, the disc disappears while you are holding down a key to indicate that you are experiencing MIB. In an attempt to re-create the demonstration in a non-interactive format, this movie simply makes the yellow disc disappear repeatedly at a regular interval, for about 1.5 seconds at a time. You should try to experience MIB for as long as possible, so that one of the regular physical disappearances occurs when the yellow disc is already invisible. Wait for this to happen, and note what you see... At the moment of the physical disappearance, most observers will momentarily perceive the disc reappear for just a very brief moment as either a dark-blue flash (the 'after-image') or as the yellow disc itself (the 'actual-image'). Try it several times! It helps to attend carefully to the location of the disc (while keeping your eyes still, fixated on the white circle), even when you can't see it during MIB.
Movie #3 (The Rotating Line) (disrota.mov: 4526 kbytes)
Instructions. Try to experience the effect in movie #2 several times before moving on to movie #3. Note that the percept triggered by the physical disappearance of the disc in movie #2 happens without the physical presence of the disc on the screen -- since the signal that triggers the percept is just the instantaneous physical disappearance itself! Instead, this percept must be generated from some internal visual representation. Now consider: when was this representation stored? Because the yellow disc never changed in movie #2, its representation (that reappears as the flash, coinciding with the physical disappearance) could have been stored during the last moment of conscious experience, just before it disappeared due to MIB. Alternatively, this representation may reflect the state of the object during MIB, even when you can't see it, just prior to the physical disappearance. We distinguished between these two alternatives by changing the object during MIB. In this movie, the yellow stimulus is a vertical line which rotates before it disappears. If the entire rotation occurs during MIB, what will you see when it disappears? Again, you should try to experience MIB for as long as possible, and wait for an instance when the last thing you see before MIB sets in is the vertical yellow line. Then try to maintain MIB until the physical disappearance, and note what you see: a sudden brief flash of the rotated version -- indicating that visual processing of unseen objects continues during MIB, and that this information can later reenter awareness.
Figure 1 (p5341_I.jpg: 100 kbytes)
