#Delboeuf illusion and food series#

Van Itersum K, Wansing B (2012) Plate Size and Color Suggestibility: The Delboeuf Illusion’s bias on serving and eating behavior. Perception and Psychophysics, 20, 129-137 An empirical taxonomy of visual illusions. 195–216Ĭoren S, Girgus JS, Ehrlichman H, Hakstian AR (1976). Bulletins de l’Académie Royale des Sciences, Lettres et Beaux-arts de Belgique, 19, 2nd ser. Why is this stronger than the animation above? Sourcesĭelboeuf, Franz Joseph (1865) Note sur certaines illusions d’optique: Essai d’une théorie psychophysique de la manière dont l’oeil apprécie les distances et les angles. relative gap between the edge of the food and the edge of the dinnerware. I composed the neighbouring food example with exactly identical burgers on both plates – I can’t believe it myself. The results of five studies suggest that the neglected Delboeuf illusion may. So, in a cafeteria, choose a smaller plate! Plate size has increased over the last 100 years by ≈15%, and this may in part explain why most of us (well, me at least) eat too much. If I find this illusion rather “mild” and open to cognitive modulation (and did not even read the original French publication), why did I go to the effort to include it in my collection? Because there is this titillating paper by Ittersum & Wansing (2012), which to me rather convincingly demonstrates that plate size influences the amount we eat – even nutritional experts fall for it. As such these cognitive size illusions are less “cognitively impenetrable” than the perspective-related size illusions. For me this illusion is rather fleeting: Its strength varies, sometimes it does not seem to be present at all. show with a factor analytical approach), but not size illusions which relate to depth perception / perspective. Into the same class belongs the Ebbinghaus-Titchener illusion (as Coren et al. (1976) put it “(This) is some sort of cognitive contrast effect, where in general the apparent difference in the size of the central test element and adjacent or surrounding elements is accentuated.” Helmholtz referred to it as “size contrast.” These illusory effects depend upon cognitive information processing strategies.

#Delboeuf illusion and food series#

In a study published in Appetite, a team of Israeli researchers tested hungers influence on the Delboeuf illusion in a series of experiments.

The number below this button gives the current size difference of the blue disks in %. A 2014 paper in the International Journal of Obesity reached a similar conclusion, finding participants overestimated the sizes of food portions when served on plates with wider rims. In all likelihood, your careful adjustment will now look totally out of place. If they look sufficiently equal, tap “ exchange + %”, and the circles will switch places. As soon as you move the slider, the automatic circle interchange stops and you can adjust at your leisure. With the slider on the very right you can adjust the relative sizes of the blue circles. This effect is moderately strong but fully illusory. The black circles exchange place every few seconds, and you may notice that the blue disks seem to change in size. One circle is a little larger than the blue disks, the other much larger. Above you see two blue disks, and two black circles.