The effects of mirror confrontation on self-estimation of body dimensions in anorexia nervosa, bulimia and two control groups.

Using an apparatus which provides a continuous horizontal slit of light of variable length, self-estimations of 4 body widths were carried out before and after a mirror confrontation procedure on 4 groups of young female subjects--anorexic, bulimic, emotionally disturbed and normal. The results confirm that anorexic subjects overestimate body size, although in this study the hip diameter was frequently underestimated. Bulimic and emotionally disturbed subjects overestimate to much the same degree as anorexics, whereas normal subjects are remarkably accurate with the exception of the head width. Mirror confrontation resulted in reduced estimations in the majority of subjects, but significant differences were found in the degree to which this occurred in the 4 groups; anorexic subjects showed the greatest change and normal subjects the least. This relative instability of the anorexic subject's body image cannot be explained simply on the basis of a self-correcting experience, as many estimations which were initially below actual width were even lower on re-testing. In the anorexic and bulimic groups a significant correlation was found between the degree of overestimation after mirror confrontation and progress in treatment, as measured on a specially devised rating scale. Possible explanations for these findings and their diagnostic and prognostic implications are discussed.