James Cooke, of Islip,N.Y.,can't recognize other people. "I see eyes, nose, cheekbones, but no face," he said. "I've even passed by my son and daughter without recognizing them."  He is not the only one. Those with prosopagnosia, also known as face blindness, can see perfectly well, but their brains are unable to piece together the information needed to understand that a collection of features represents an individual's face. The condition is a neurological mystery, but new research has shed light on this strange disease.  Some scientists had believed that faces and voices, the two main ways people recognize one another, were processed separately by the brain. Indeed, a condition parallel to prosopagnosia, called  _ , similarly leaves a person unable to distinguish a familiar voice from an unfamiliar one. But by testing for these two conditions at the same time, researchers at the Max Planck Institute recently found evidence that face and voice recognition may be linked in a unique person-recognition system. The scientists observed the brain activity of 19 healthy volunteers as they were led through tasks that tested their ability to recognize both faces and voices. The researchers found that regions of the brain, associated with facial recognition, are directly linked to regions responsible for voice recognition.  This research helps explain why a person with prosopagnosia may still have difficulty determining who a person is even after he has begun to speak. The challenge for scientists is to find out where this system breaks down. Are these connections in the brain missing entirely, or are people unable to recognize faces and voices simply unable to use these links in some way?  It is unclear how many people have these conditions. Many don't even realize they have problems with facial or voice recognition. While some develop these difficulties after a brain injury, others develop it in childhood. James Cooke can't recognize other people because  _  .
his eyesight is failing he prefers to walk hurriedly he suffers from face blindness he can't tell facial expressions