Perception and obesity: The effect of actual body size and beliefs about body size on perception of the environment

Mila Sugovic, Purdue University


Action abilities are constrained by physical body size and characteristics, which, according to the action-specific account of perception, should influence perceived space. I examined the extent to which physical body size and beliefs about body size affect spatial perception. This was implemented by taking advantage of naturally-occurring dissociations typically found to occur in people who are obese and underestimate their weight. Normal weight, overweight, and obese individuals made perceptual estimates of distance, slant, and aperture widths. Both measurements of beliefs about body size and measures of actual physical body size were obtained. Obese individuals estimated distances to be farther, hills as steeper, and aperture widths to be smaller than did non-obese individuals. Furthermore, actual body size influenced perceived distance, perceived hill slant, and perceived aperture width whereas beliefs about body size did not contribute to these perceptions. Thus, whereas perception is influenced by physical characteristics, it is not influenced by beliefs. Therefore, action-specific perception effects are indeed effects of actual abilities regardless of a person's beliefs about abilities. The results also demonstrated that people who are obese perceive the world differently compared with those who are not obese. These differences could contribute to lifestyle choices.




Witt, Purdue University.

Subject Area

Cognitive psychology

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