Spatial knowledge in a young blind child.

A set o f eight experiments demonstrate spatial knowledge in a 2-year-old congenitally blind child and sighted blindfolded controls. Once the blind child had traveled along specific paths between objects in a novel array, she was able to make spatial inferences, finding new routes between those objects (Experiment I). She could also do so when the routes were between places in space, not occupied by objects (Experiment II). Deviations from precisely straight routes in Experiments I and H were not due to faulty inferences, but probably came from imprecise motor control, since the same deviations occurred when inferences were not required--when the child moved to a place designated by a sound source (Experiment 111). This child's performances could not be accounted for by artifactual explanations: sound cues, experimenter bias, and echolocation were ruled out (Experiments IV, V, VI). Further. sighted blindfolded controls performed at roughly the same level (Experiment VII). Finally, Experiment VIII shows that the blind child could access her spatial knowledge for use in a simple map-reading task. We conclude that the young blind child has a system of spatial knowledge, including abstract, amodal rules *We wish to thank Lila R. Gieitman for extensive conceptual, editorial, and per,,;onal support in every phase of this project. 'We also thank C.R. Gallistel for suggesting several experimental ideas, and for pointing out the relevance of a geometrical approach to spatial knowledge. We thank the O'Brien family for their extensive commitment to this work. Finally, we thank Dr. G. Pereira and Ms. Anne Farren for locating our blind subject, and Kathy Feldman, Marcia Glicksman, and Lenora Knapp for assi:~aance in running subjects a~:d coding data. All of the work reported in this paper was supported by a Social and Behavioral Sciences Research Grant from the National Foundation-March of Dimes to Lila R. Gleitman and Barb~:ra Landau; a Sioan Foundation Post-Doctoral Fellowship and a National Research Service Award from N.I.M.H. to Barbara Landau; and a N.I.C.H.D. award to Elizabeth Spelke. Portions of Experiments I, IV, and VII were first rept t in Landau, Gleitman and Spelke (1981). Figures 1 and 2 have been adapted from drawings that appeared in Landau, Gleitman and Spelke (1981, pp. 1275 (Fig. 1) and 1276 (Fig. 2)). Reprint requests should be addressed to: Barbara Landau, Department of Psychology, Columbia University, 315 Schermerhorn Hall, New York, New York 10027, U.S.A. 6010-0277/84/$11.30 © Elsevier Sequoia/Printed in The Netherlands 226 B. Landau et al. and principles that incorporate metric geometric information that can be used to guide navigation about the world.