Report on the 1975 Conference on Pictorial Perception at the University of Minnesota, U.S.A.

Leonardo, Vol. 9, pp. 311-313. Pergamon Press 1976. Printed in Great Britain REPORT ON THE 1975 CONFERENCE ON PICTORIAL PERCEPTION AT THE UNIVERSITY OF MINNESOTA, U.S.A. Albert Yonas* and Robert Cooper** 1. Introduction A group of psychologists met at the University of Minnesota from 29 July to 1 August 1975 to discuss current research on picture perception [l]. The purpose of the Conference was to evaluate the present state of knowledge of the way children and adults perceive pictures, to speculate on the implication of this knowledge for general issues in perceptual and cognitive psychologyand to outlinedirectionsfor future research. The discussion focused primarily on the ‘dual‘ nature of pictures that give an illusion of 3-dimensional objects on a plane surface. Three approaches to this dual nature were presented:, (1) the types of information contained in representationalline drawings and photographs , (2) the types of information in such drawings that are different from those in real objects but are related to them by rules of projective geometry or perspectiveand (3) the special features of such drawings that apparently are not directlyrelated to the perception of real objects, as for example conventions for representing motion. These approaches provide a framework for investigating the development of picture perception by humans. An insightthrough the first approach can be obtained by studyingthe way in which childrensee line drawings of real objects and whether or not their perception of such pictures changes with their age. The second approach involves the study of children’s interpretations of relationships between nonisomorphic but rule-governed pictorial representations of objects and the appearance of real objects. The rules are unique to this type of pictorialrepresentation and the information obtained from such pictures differs from that provided by the ‘laws of perception’ of real objects. Once the rules have been learned, however, the actual eyelbrain processing of the information obtained may be similar to that used for the perception of real objects. The third approach is concerned with the following questions : Are there universal aesthetic principles underlyingpictures or do pictures contain artisticconventions that must be learned? If there are not aesthetic principles to which a human automatically responds, how does an individual learn to interpret the conventions and what is the basis of an aesthetic response to them? *Psychologist,Institute of Child Development, University of Minnesota, Minneapolis, MN 55455, U.S.A. **Psychologist, Dept. of Psychology, University of Texas Austin TX 78712, U.S.A. (Received 26 Mar. 1976). 2. Summary of the discussions A. Information in representational line drawings and The question most often raised was the familiar one as to whether the perception of depth of real and of depicted objects is innate or learned. Recently T. G. R. Bower published a report on this subject for nonspecialists [2]. He states that it appears that while young infants are sensitive to the depth information provided by the relative motion of real objects when the head is moved, depth information that is ‘frozen’ into pictures of objects by resort to perspective, superposition, etc. is not detected by them. R. Olson reported on research that leads to the tentative conclusion that two-and three-year-olds can make use of superposition in pictures to make near-far judgments (Fig. 1) [3]. When relativesizewas the only information for a 3-dimensional interpretation, the children showed little perception of depth. They may have been making use of the knowledge that real objects often vary in size and since size is not a consistentlyinformative cue in the real world, it may also be a poor cue in pictures. Response to the cue of height on the picture plane photographs Fig. 1. Display of relative size, superposition and height on the picture plane for judging pictorial depth. 311 312 Albert Yorias and Robert Cooper proved a more complex matter. In the absence of information for a surface receding in depth, K. Benson and I (A. Y.)have found that depictions of objects at different heights on the picture plane do not suggest to young children that the objects are to be interpreted as being at different depths [4]. But Olson has found that by simply adding a contour indicating the horizon, height...