but instead of helping him, people just walked on by. overlooking a sidewalk in queens, new york, a security camera records a woman walking along the street. police say she s about to be the victim of a violent mugging. the attacker, wearing dark pants and a green hat, approaches her. he s armed with a knife. police say a man comes to her aid. she is hugo alfredo tale-yax, a homeless day laborer. the attacker turns on him and police say stabs him several time in the chest. tale-yax turns to chase the man who s just stabbed him, but after only a few steps, he collapses on the sidewalk. what happens next is difficult to comprehend. people walk by without stopping to help him. they come and go, more than 20 of them. some glance over at the dying man. others stare. these two men stop, nearby, they stand there before one of the men takes out his cell phone and takes a picture.
after only a few steps, he collapses on the sidewalk. what happens next is difficult to comprehend. people walk by without stopping to help him. they come and go, more than 20 of them. some glance over at the dying man. others stare. these two men stop, nearby, they stand there before one of the men takes out his cell phone and takes a picture. another turns tale-yax over, presumably sees his wounds, but like the others, walks away. for more than an hour, dozens of pedestrians and bystanders walk past this hero who saved a life, apparently without ever calling 911. finally, firefighters respond to the scene, but it is too late. hugo alfredo tale-yax is dead. it s a shocking story, i ll tell you, but we ve seen it before. it s called bystander behavior, in which people do nothing to save someone else s life. but it could be something else as well. and that s the response mechanisms in our brains. that could be changing. we re digging a little deeper now. joining me now is psychologist m