In the house of alleged Cleveland kidnapper Ariel Castro, multiple padlocks kept interior doors shut, windows were nailed shut, and guests weren't allowed upstairs or in the basement.
In retrospect, some question why visitors didn't notice that something was amiss over the 10 years that three women were allegedly held captive there before their recent escape. But psychologists say few people would: We are so focused on the task on hand that it's easy to miss aberrant details.
In fact, psychologists Christopher Chabris and Daniel Simons found that half of people watching a video failed to notice a man dressed in a gorilla suit walking through a basketball game when they were told to count the number of passes among team members. Still, we think we notice things.
"We have a bias to believe that we will notice all the important things," said Chabris, a professor at Union College and co-author with Simons of "The Invisible Gorilla".
In another experiment, Chabris and Simons staged a fake fight along a path and had subjects run past while chasing someone.
“Many did not notice [the fight],” Chabris said. “The thing you think is salient -- people fighting -- should grab your attention, but if you’re chasing a suspect it’s shockingly easy to miss things that in retrospect seem obvious.”
So, padlocks on doors in a grimy house? It's entirely plausible that a neighbor going to borrow an egg, for instance, wouldn't see them.
"You're not going over there with the task of looking for something unusual," Chabris said.
Our brains form fast, general categorizations of our surroundings, said Barbara Tversky, a psychology professor at Teachers College, Columbia University.