The caricature effect in drawing: evidence for the use of categorical relations when drawing abstract pictures.

Five experiments were conducted to determine how novice and expert drawers represent relative size for the purposes of drawing. Participants were shown images of two-part or three-part geometric figures composed of two spatially separated shapes. In each picture there was a small but noticeable relative-size difference between the constituent shapes (one part of the picture was always 25% larger than another part). Participants later drew the pictures from memory. The results showed that novice and expert drawers consistently exaggerated the relative size relationship between the shapes in the picture when attempting to draw it from memory and when copying (the 'caricature effect'), although the effect was reduced for the experts. The results are consistent with the idea that people represent size in memory using categorical descriptors (e.g., 'smaller than', 'larger than') rather than as precise metrics. Further, the results suggest that the process of becoming a skilled drawer may involve overcoming this categorical bias.