The Perky Effect
While some of Titchener's work has "long since fallen into disrepute," the work performed in his lab in 1910 by Perky has "achieved something of a classic, even mythic, status in the literature on imagery." Perky's famous experiments demonstrated how sensory input, or perceptions, can be mistaken for a mental image when perceptual processes and mental imagery interfere with each other. Now known as the Perky Effect, her research described the result when a subject's visual perception is altered by mental imagery. To test her hypothesis,Perky trained her participants to look at a blank screen and try to imagine an object such as a banana. She then asked her participants to fixate a point on a screen in front of them and to visualize various objects there, such as a tomato, a book, a leaf, a banana, an orange, or a lemon. As the subjects did this, and unbeknownst to them, a faint patch of color, of an appropriate size and shape, and just above the normal threshold of visibility, was back-projected (in soft focus) onto the screen. Participants, believing that they were visualizing an object of their choice, typically reported an object that matched the shape and colors of the projected shapes. Perky had led them to assume that a physical stimulus was imagined.The images were projected at a very low brightness to start and gradually increased in brightness. The participants were asked to describe the objects that corresponded to the image that was being projected.
...none of Perky's subjects (who ranged from a ten year old child to the trained and experienced introspectors of Titchener's laboratory) ever realized that they were experiencing real percepts; they took what they “saw” on the screen to be entirely the products of their imagination. In fact, however, the projections did influence their experiences.Participants reported that they believed they were imagining the projected images rather than actually perceiving them and they reported “seeing” the mental images in greater detail than what was actually presented in the stimulus. Imagery can be derived from short and long-term memories. Perky also distinguished between "images of memory" and "images of imagination." Images of memory are personal episodic images and are associated with more eye movements and feelings of familiarity. Images of imagination are more general, have little meaning to an individual, and may be associated with feelings of surprise. The Perky Effect, which describes the link between mental imagery and visual perception, has been a foundation for continued research in visual perception and imagery. Her studies have inspired replications and further exploration of the different ways that perception and imagery can affect things like visual acuity.
Selected works
* Perky, Cheves West. "An experimental study of imagination." ''The American Journal of Psychology'' 21.3 (1910): 422-452. * Perky, Cheves West. ''Cooperation in the United States''. Intercollegiate Socialist Society, 1919. * Perky, Cheves West. "Children in the Museum." ''Bulletin of the Pennsylvania Museum'' 27.143 (1931): 11-14.Literature
* Cooper, Cooper Sarah. ''Film and the Imagined Image''. Edinburgh University Press, 2019. * Proctor, Robert W., and Rand Evans. "EB Titchener, women psychologists, and the experimentalists." ''The American journal of psychology'' 127.4 (2014): 501-526. * Calabi, Clotilde. "The Far Side of Things: Seeing, Visualizing and Knowing." ''Mind, Language and Action''. De Gruyter, 2015. 335-346. * Berger, Christopher C. ''Where imagination meets sensation: mental imagery, perception and multisensory Integration''. Inst för neurovetenskap/Dept of Neuroscience, 2016. * Dijkstra, Nadine, Peter Kok, and Stephen Fleming. "Perceptual reality monitoring: Neural mechanisms dissociating imagination from reality." (2021). * Waller, David, et al. “A Century of Imagery Research: Reflections on Cheves Perky's Contribution to Our Understanding of Mental Imagery.” ''The American Journal of Psychology'', vol. 125, no. 3, 2012, pp. 291–305. ''JSTOR'', www.jstor.org/stable/10.5406/amerjpsyc.125.3.0291. Accessed 30 June 2021.References