Jaeger, T., & Long, S. (2007). Effects Of Contour Proximity And Lightness On Delboeuf
Illusions Created By Circumscribed Letters. Perceptual and Motor Skills, 105(5), 253. doi:10.2466/pms.105.5.253-260 Jaegar and Long conducted a study on how having large surrounding circles and reducing the lightness contrast of the outer ring can decrease the effects of the Delboeuf and circumscribed letters illusions. For their experiment, researchers printed out illusion figures, which had circles that had a central “S” or “A” letter. There was a combination of circle and letter sizes: black outer ring with inner grey letter, black outer ring and inner letter, grey outer ring with central black letter, and grey outer ring and letter. There were 32 participants, …show more content…
Additionally, Nicolas criticizes other studies that discuss the illusion from 1892 to 1893; he argues that these studies do not respectively correlate with Delboeuf’s original research. The author discusses Delboeuf’s three articles on visual illusions and examines his data and process on obtaining information of the concentric circle illusions. In 1865, Delboeuf started his first study on visual illusions. He presented a theory about all optical and visual illusions; Delboeuf stated that muscular strength is an important concept in illusions. He stated that the eye’s medial and lateral muscles are stronger than inferior and superior muscles. Therefore, less muscular effort is needed when measuring a horizontal line compared to a vertical one with the same length. In his second study, Delboeuf hypothesized that a white disk on a black background looks larger than a black disk on a white background. Additionally, he stated that inner rings make the central circle appear smaller, while outer rings make the central circle appear larger. He also revealed that having knowledge of the illusion and practice do not have a significant effect on the illusion. In 1892, Delboeuf released a publication about his third experiment, in which participants had to compare between the inner circle’s diameter and the outer circle’s diameter, even though both circles had identical diameters. He concluded that people tend to overestimate the inner circle’s diameter compared to the outer circle’s diameter. In addition, Nicolas respectfully viewed Delboeuf of being a pioneer in experimental studies of optical
Illusions Created By Circumscribed Letters. Perceptual and Motor Skills, 105(5), 253. doi:10.2466/pms.105.5.253-260 Jaegar and Long conducted a study on how having large surrounding circles and reducing the lightness contrast of the outer ring can decrease the effects of the Delboeuf and circumscribed letters illusions. For their experiment, researchers printed out illusion figures, which had circles that had a central “S” or “A” letter. There was a combination of circle and letter sizes: black outer ring with inner grey letter, black outer ring and inner letter, grey outer ring with central black letter, and grey outer ring and letter. There were 32 participants, …show more content…
Additionally, Nicolas criticizes other studies that discuss the illusion from 1892 to 1893; he argues that these studies do not respectively correlate with Delboeuf’s original research. The author discusses Delboeuf’s three articles on visual illusions and examines his data and process on obtaining information of the concentric circle illusions. In 1865, Delboeuf started his first study on visual illusions. He presented a theory about all optical and visual illusions; Delboeuf stated that muscular strength is an important concept in illusions. He stated that the eye’s medial and lateral muscles are stronger than inferior and superior muscles. Therefore, less muscular effort is needed when measuring a horizontal line compared to a vertical one with the same length. In his second study, Delboeuf hypothesized that a white disk on a black background looks larger than a black disk on a white background. Additionally, he stated that inner rings make the central circle appear smaller, while outer rings make the central circle appear larger. He also revealed that having knowledge of the illusion and practice do not have a significant effect on the illusion. In 1892, Delboeuf released a publication about his third experiment, in which participants had to compare between the inner circle’s diameter and the outer circle’s diameter, even though both circles had identical diameters. He concluded that people tend to overestimate the inner circle’s diameter compared to the outer circle’s diameter. In addition, Nicolas respectfully viewed Delboeuf of being a pioneer in experimental studies of optical