Cognitive psychologists have often likened human memory to a computer that encodes, stores, and retrieves information. It is now clear, however, that remembering is an active process and that people construct and alter memories according to their beliefs, wishes, needs, and information received from outside sources.
Without realizing it, people sometimes create memories that are false. In one study, for example, subjects watched a slide show depicting a car accident. They saw either a “STOP” sign or a “YIELD” sign in the slides, but afterward they were asked a question about the accident that implied the presence of the other sign. Influenced by this suggestion, many subjects recalled the wrong traffic sign. In another study, people who heard a list of sleep-related words (bed, yawn) or music-related words (jazz, instrument) were often convinced moments later that they had also heard the words sleep or music—words that fit the category but were not on the list. In a third study, researchers asked college students to recall their high-school grades. Then the researchers checked those memories against the students’ actual transcripts. The students recalled most grades correctly, but most of the errors inflated their grades, particularly when the actual grades were low.