SPATIAL HEARING IN CHILDREN WITH VISUAL DISABILITIES

A study is reported of the effect of early visual experience on the de velopment of auditory space perception. The spatial hearing of thirty- five children with visual disabilities (twenty-two with congenital tot al blindness) was compared with that of eighteen sighted children and seventeen sighted adults. The tests provided a comprehensive assessmen t of spatial-hearing ability, including psychophysical estimates of sp atial resolution in the horizontal, vertical, and distance dimensions, as well as measures of reaching and walking to the locations of sound sources. The spatial hearing of the children with visual disabilities was comparable to or somewhat better than that of the sighted childre n and adults. This pattern held even when the group with visual disabi lities was restricted to those children with congenital total blindnes s; in fact, some of those children had exceptionally good spatial hear ing. These findings imply that the developmental calibration of human spatial hearing is not dependent on a history of visual experience. It seems likely that this calibration arises from the experience of chan ges in sound-localization cues arising from self-motion, such as turni ng the head or walking. As a practical matter, orientation and mobilit y instructors may reasonably assume that individuals with visual disab ilities can use their hearing effectively in day-to-day travel situati ons.