The development of pictorial depth perception: the role of figural elevation.

This is a follow-up of a previous study (Jahoda & McGurk, 1974), in which pictorial depth cues were systematically manipulated. In Expt. I children aged between 4 and 10 were presented with stimulus pictures in which depth cues were reduced to elevation and walking or standing posture of two figures. In one condition a training picture reminding subjects of the actual size relations remained visible, in order to test for possible memory effects, and in the other condition it was absent. As before, children were required to construct three-dimensional models representing the size and spatial relationships between figures in the pictures, scoring being in terms of size and spatial accuracy. Results were consistent with previous ones, indicating that elevation alone constitutes a relatively weak but effective depth cue. There was a moderate memory effect, posture being insignificant. Expt. II was designed to test the hypothesis that the difficulties experienced by younger subjects are response rather than perceptually based. Children aged 4 and 6 were given the task of reproducing a three-dimensional model. Subjects had no difficulty with size, but spatial responses were at a very low level at the age of 4, increasing significantly in accuracy by the age of 6. The predominant error at both age levels was horizontal instead of diagonal orientation. This is in conformity with the hypothesis and consistent with previous results.