Do you remember where you were when you heard about a traffic accident of involving a close friend?The answer is probably yes. Do you remember what you were doing on your birthday that year?You may have to think a little harder.
People remember bad memories more easily and in greater detail than good ones. Why is that?A new study found that people do this because of evolutionary (进化的) reasons.
Elizabeth Kensinger and her partners at Boston College, US, did a study looking at this. They found negative feelings like fear and sadness cause an increase in brain activity. This activity happens in the part of the brain that controls memories. So memories caused by negative feelings are kept in greater detail than other kinds of memories.
For example, after seeing a man on a street holding a knife, people remember the knife clearly, but they forget the details of the street.
According to Kensinger, it is easy to understand this from an evolutionary point of view. She said that people pay attention to dangerous information so they can use that information to guide their actions and save their lives. They can also use it to plan for similar events in the future.
The scientists say more studies are needed on how we remember bad memories. This line of research could help solve stress disorders.