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POPSBlurring the Boundary Between Perception and Memory
Memory itself is not like a video-recording, with a moment-by-moment sensory image. In fact, it’s more like a puzzle: we piece together our memories, based on both what we actually remember and what seems most likely given our knowledge of the world. Just as we make educated guesses in perception, our minds’ best educated guesses help “fill in the gaps” of memory, reconstructing the most plausible picture of what happened in our past. The most striking demonstration of the minds’ guessing game occurs when we find ways to fool the system into guessing wrong. When we trick the visual system, we see a “visual illusion”—a static image might appear as if it’s moving, or a concave surface will look convex. When we fool the memory system, we form a false memory—a phenomenon made famous by researcher Elizabeth Loftus, who showed that it is relatively easy to make people remember events that never occurred. As long as the falsely remembered event could plausibly have occurred, all it takes
15
POPSDistorted Body Images: A Quick and Easy Way to Reduce Pain
For the study, Lorimer Moseley of Oxford University and his colleagues recruited 10 participants, all of whom suffer from chronic pain in their right arm. The participants were asked to perform a set of movements with their right arm, under different conditions. In one condition, they observed their limb through a pair of binoculars, which magnified their hand to twice its normal size; in another, the binoculars were inverted so that their hands appeared smaller than they actually were. As they performed the arm movements, the participants were asked to rate the amount of pain they experienced. Each one reported that the pain they felt became markedly worse when they moved their limb. Surprisingly though, every participant also reported that the extent to which their pain increased depended on how their vision had been manipulated. They reported the greatest increase in pain when they saw a magnified view of their hand, and the smallest increase when their hands were minified.