朝活ミニテスト 第14回

Why We Remember Wrongly

Many people imagine memory as a kind of video recording that can be replayed exactly as it happened. Research, however, shows that memory is far more flexible and less reliable. Each time we recall an event, the brain reconstructs it from fragments, filling in gaps with expectations and information acquired later. In a famous series of experiments, psychologist Elizabeth Loftus showed participants a film of a car accident and then asked how fast the cars were going when they either hit or smashed into each other. Those who heard the word smashed gave higher speed estimates and were more likely to later report seeing broken glass, even though there was none.

Later studies went further, suggesting that people can sometimes be led to remember entire events that never happened, such as being lost in a shopping mall as a child. Some researchers, however, question how often this occurs outside the laboratory, and many emphasize that memory is not simply unreliable. People usually remember the general outline of important experiences quite accurately; it is specific details, such as colors, times, and exact words, that are most easily distorted.

Such findings have had important consequences for the legal system. Eyewitness testimony, once considered highly persuasive evidence, is now recognized as a significant factor in wrongful convictions. In response, some police departments have changed how they conduct identification procedures, for example by having photographs shown to witnesses by officers who do not know which person is the suspect. Researchers also recommend recording how confident a witness is at the first identification, since confidence tends to grow over time and may no longer reflect accuracy by the time a case reaches court.