单选题 Folk wisdom holds that the blind can hear better than people with sight. Scientists have a new reason to believe it. Research now indicates that blind and sighted people display the same skill at locating a sound" s origin when using both ears, but some blind people can home in on sounds more accurately than their sighted counterparts when all have one ear blocked. Canadian scientists described the work in the Sept. 17 NATURE. Participants in the study were tested individually in a sound-insulated room. They faced 16 small, concealed loudspeakers arrayed in a semicircle a few feet away. With a headrest keeping their heads steady, the participants pointed to the perceived origins of the sounds. The researchers tested eight blind people, who had been completely sightless from birth or since a very early age. They also tested three nearly blind persons, who had some residual vision at the periphery of their gaze; seven sighted people wearing blindfolds; and 29 sighted people without blindfolds. All participants were tested beforehand to ensure that their hearing was normal. When restricted to one-ear, or monaural, listening, four of the eight blind people identified sound sources more accurately than did the sighted people, says study co-author Michel Pare, a neuroscientist at the University of Montreal. The sighted people showed especially poor localization of sounds from the speakers on the side of blocked ear. In sighted people who can hear with both ears, " the brain learns to rely on binaural [ stereo ] cues. These data suggest that blind people haven" t learned that and keep monaural cues as the dominant cues," says Enc I. Knudsen, a neurobiologist at Stanford University School of Medicine, "I find it surprising. "