Specific spatial defect in a child with septo-optic dysplasia.

A blind girl with septo-optic dysplasia was compared with a blind, age-matched control on three spatial tests. Previous observations had suggested a specific spatial learning disorder. Results of the tests showed good verbal intelligence but severe impairment of topographical orientation, route-learning and kinaesthetic memory. It is argued that these dysfunctions were a direct consequence of the malformation syndrome, and could not be accounted for by factors such as sex or congenital blindness.