blind spot

            “Beliefs can easily cause us to become blind to the obvious.  Recent research on ‘inattentional blindness’ has shown that even minor tweaks to one’s expectations can cause a form of blindness.  A simple experiment developed by University of Illinois psychologist Daniel Simons provided a dramatic demonstration of this effect.  …

            Simon’s experiment consists of a twenty-five second video clip of six people playing a basketball game.  Three are dressed in white T-shirts and three in black T-shirts.  The white team is passing a basketball amongst themselves, and the black team is doing likewise.  During the game, a person dressed in a black gorilla suit calmly walks into the middle of the game, beats its chest, and then walks off.  The gorilla is not understated or camouflaged – it’s blatantly obvious.  And yet the majority of people viewing the clip do not see the gorilla provided they’re given a very simple instruction:  count the number of basketballs tossed between the members wearing white T-shirts.  This minor deflection of attention is enough to cause complete blindness to something as obvious as a gorilla.  The power of deflecting attention is well known to stage magicians, who specialize in creating such illusions.”