by Tom Morris
Overweight and obese people see distances as at least ten percent longer than skinnier people do. It’s not just that extra distance means extra effort – it really is the case. Spatially in the brain, a mile is perceived as a greater distance the heavier you are.
Psychologist Dr Jessica Witt, who investigates the perception of spatial layout, has published a few papers on the subject as well as most recently giving a talk. She wrote that “a person’s ability to perform an action affects their perception of the environment.” This makes a lot of sense, think about how short a walk it seemed to the Students’ Union from Talybont when you were in first year, but now, as you’re not used to the walk, you probably wouldn’t bother going up there. I’ve heard plenty of second and third years say “I’ve got an exam/sport up in Talybont, oh it’s such a long walk,” when they no doubt did it every day just a few months before.
Witt found that when throwing a ball the same distance, the target seemed further away if the ball was heavier. For the obese participants, extra effort was applied mentally to walking the same distance as a fit person breezed through, and thus was judged as being a longer walk. The effect was seen to apply to gradients as well as a hill may appear steeper to a heavier person that it might seem to someone slimmer.
These two effects were not apparent as much in those who were just overweight as those who were obese. According to the study, a person weighing 23 stone sees objects as being twice as far away as someone who weighs nine stone.
To put it simply, obese people have more anticipated effort for walking which leads to increased judgement of distances.
The study also found some interesting anecdotes about body image. If an obese person only perceived themselves as overweight it made no difference, they would still have the adverse effects on judgement as their obese friends who more easily admitted to their size.
These findings seem to show that obese people live in what one reporter called an “altered reality,” where the extra effort caused by being heavier manifests itself as a world where everything is further away.