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A good deal of the information stored in working memory is encoded in a(n) ______ form, especially when the information is language based. (a) _______, in an early study by Conrad, adults were shown six-letter sequences, with letters being presented visually, one at a time, at intervals of three-fourths of a second. As soon as the last letter of a sequence had been presented, participants in the study wrote down all six of the letters they had seen, guessing at any letters they couldn’t easily recall. When people recalled letters incorrectly, the letters they said they had seen were more likely to resemble the actual stimuli in terms of how the letters sounded than how they looked.