Body image distortion in anorexics as a non-sensory phenomenon: a signal detection approach.

Body image in anorexic and normal weight female subjects was investigated with a video TV monitor. Eighteen subjects were presented with a task in which they manipulated their body size to obtain "ideal" and actual images and a task wherein they judged the accuracy of a projected image of their body. There were no differences in estimated actual body size between anorexics and control subjects. For both groups, ideal images were below their actual image. For the second task, a signal detection analysis revealed no sensory sensitivity differences between weight groups. Anorexic subjects were more likely to report an image of themselves as distorted, regardless of whether distortion was present. Both weight groups adopted a strict criterion when they were viewing a heavy image of themselves. The finding that body estimation difference between anorexics and controls is non-sensory are discussed, and ramifications for treatment of anorexia are described.