Why we're good at finding lost things

Something as simple as finding your car keys -- a visual search -- is a task computers are inefficient at despite decades of advancement, U.S. researchers say. Researchers at the University of California, Santa Barbara, said they wanted to know how a human brain could accomplish in seconds a search that a computer, even with its massive calculating power, takes much longer to accomplish. "Our daily lives are composed of little searches that are constantly changing, depending on what we need to do," Miguel Eckstein, a professor of psychological and brain sciences, said. "So the idea is, where does that take place in the brain?" The researchers said they wanted to determine how we decide whether the target object we are looking for is actually in the scene, how difficult the search is, and how we know we've found what we wanted. The answer, they found, lies in the dorsal frontoparietal network, a region of the brain that roughly corresponds to the top of the head and associated with properties such as attention and eye movements. Researchers used a magnetic resonance machine to monitor the brains of subjects looking for certain items in a scene. "As you go further up in processing, the neurons are less interested in a specific feature, but they're more interested in whatever is behaviorally relevant to you at the moment," Eckstein said in a university release. For example, he said, a search for an apple would make red, green and rounded shapes relevant. If the search was for your car keys, the frontoparietal network would now be interested in gold, silver and key-type shapes and not interested in green, red and rounded shapes. "For visual search to be efficient, we want those visual features related to what we are looking for to elicit strong responses in our brain and not others that are not related to our search, and are distracting," Eckstein said. "Our results suggest that this is what is achieved in the intraparietal sulcus, and allows for efficient visual search."