What do you see in the picture above? This piece “Message d’amour des dauphins” by Sandro del Prete depicts a man and woman in a provocative pose. Or does it? Some people see the couple, but others see something else-dolphins. There exists research that suggests that the differences in perception are due to perceptual priming. Priming refers the phenomenon where the exposure of one stimulus influences the perception of another (Kolb & Whinshaw 2003). In this case, individuals who are more exposed to sexual images are more likely to see the couple, and likewise, those who have very little exposure to sexual images (presumably children) are more likely to see the dolphins. However, this is only one explanation. Research by Patrick Cavanagh shows that darkness contrasts in images are perceived as shadow (Cavanagh 2005). In del Prete’s image, the dolphins are darker than the “skin” of the bodies and are therefore perceived as shadows. To test whether or not this could account for the perception of the human couple, I inverted the colors of the image.
This second image depicts the dolphins as lighter than what would be the “skin” of the human bodies. The dolphins in the second image should be easier to perceive than in the first image. Though the preceding text could be viewed as priming, when individuals were presented with the inverse-contrast picture first, they saw dolphins, and only saw the human couple when presented with the first image. The results of this project show that although priming can and does play a major role in optical illusion perception, by simply changing one aspect of the visual input (by inverting color in this case), it is possible to increase a person's likelihood to perceive something completely different than the original image.
Sources
Cavanagh, P. (2005) The artist as neuroscientist. Nature, 434, 301-307 Del Prete, S. (2010). Official Website of Sandro del Prete. Image Retrieved December 1, 2011, from
http://www.sandrodelprete.com/#.
Kolb & Whishaw: Fundamentals of Human Neuropsychology (2003), page 453-454, 457
