An auditory illusion involving radical changes in what is heard in a clear recording of a word or phrase repeated many times on a loop of audiotape. If a single word is repeated 360 times in three minutes, the average young adult listener experiences substantial distortions and hears about 30 changes involving about six different word forms. In a classic experiment in which the word tress was used, listeners heard such words as dress, stress, Joyce, florist, purse, and even phonetically unrelated words such as lunchtime. Children under six years experience few if any transformations, and susceptibility to the effect declines slowly in middle age. The phenomenon was discovered by the US psychologist Richard M. Warren (born 1925) and the English psychologist Richard L(angton) Gregory (1923–2010) and published in the American Journal of Psychology in 1958, a more detailed account being provided by Warren in the journal Psychological Bulletin in 1968. Compare semantic satiation.