In early 2015, a public debate about a perceptual phenomenon that impressively demonstrated the subjective nature of human perception was running round the globe: the debate about #TheDress, a poorly lit photograph of a lace dress that was perceived as white–gold by some, but as blue–black by others. In the present research (N¼48), we found that the perceptual difference between white–gold perceivers (n1¼24, 12 women, Mage¼25.4 years) and blue–black perceivers (n2¼24, 12 women, Mage¼24.3 years) decreased significantly when the illumination information provided by the original digital photo was reduced by means of image scrambling (Experiment 1). This indicates that the illumination information is one potentially important factor contributing to the color ambiguity of #TheDress—possibly by amplification of a slight principal difference in psychophysics of color perception which the two observer groups showed for abstract uniformly colored fields displaying a white–blue ambiguity (Experiment 2).
The folded paper-size illusion is as easy to demonstrate as it is powerful in generating insights into perceptual processing: First take two A4 sheets of paper, one original sized, another halved by folding, then compare them in terms of area size by centering the halved sheet on the center of the original one! We perceive the larger sheet as far less than double (i.e., 100%) the size of the small one, typically only being about two thirds larger—this illusion is preserved by rotating the inner sheet and even by aligning it to one or two sides, but is dissolved by aligning both sheets to three sides, here documented by 88 participants’ data. A potential explanation might be the general incapability of accurately comparing more than one geometrical dimension at once—in everyday life, we solve this perceptual-cognitive bottleneck by reducing the complexity of such a task via aligning parts with same lengths.
The aim of this study is to develop and test the effectiveness of a drinking-motive-tailored intervention for
adolescents hospitalized due to alcohol intoxication in eight cities in Germany between December 2011 and
May 2012 against a similar, non-motive-tailored intervention. In a randomized controlled trial, 254 adolescents
received a psychosocial intervention plus motive-tailored (intervention group; IG) or general exercises (control
group; CG). Adolescents in the IG received exercises in accordance with their drinking motives as indicated at
baseline (e.g. alternative ways of spending leisure time or dealing with stress). Exercises for the CG contained alcohol-
related information in general (e.g. legal issues). The data of 81 adolescents (age: M = 15.6, SD = 1.0;
42.0% female) who participated in both the baseline and the follow-up were compared using ANOVA with repeated
measurements and effect sizes (available case analyses). Adolescents reported lower alcohol use at the
four-week follow-up independently of the kind of intervention. Significant interaction effects between time
and IG were found for girls in terms of drinking frequency (F = 7.770, p b 0.01) and binge drinking
(F =7.0005, p b 0.05) but not for boys. For the former, the proportional reductions and corresponding effect
sizes of drinking frequency (d = −1.18), binge drinking (d = −1.61) and drunkenness (d = −2.87) were
much higher than the .8 threshold for large effects. Conducting psychosocial interventions in a motive-tailored
way appears more effective for girls admitted to hospital due to alcohol intoxication than without
motive-tailoring. Further research is required to address the specific needs of boys in such interventions.
(German Clinical Trials Register, DRKS ID: DRKS00005588).