Utilization of static and kinetic information for depth by young Malaŵians

Abstract

The utilization of static and kinetic information for depth by Malaŵian children and young adults in making monocular relative size judgments was investigated. Subjects viewed pairs of objects or photographic slides of the same pairs and judged which was the larger of each pair. The sizes and positions of the objects were manipulated such that the more distant object subtended a visual angle equal to, 80% of, or 70% of the nearer object. Motor parallax information was manipulated by allowing or preventing head movement. All subjects displayed sensitivity to static information for depth when the two objects subtended equal visual angles. When the more distant object was larger but subtended a smaller visual angle than the nearer object, subjects tended to base their judgments on retinal size. Motion parallax information increased accuracy of judgments of three-dimensional displays but reduced accuracy of judgments of pictorial displays. Comparisons are made between these results and those for American subjects.