Research has shown that people who are 60 or over date public events, such as the 1987 Hungerford massacre, in which 15 people died, up to six years earlier because they relate the public event to a time when they were younger, and in a more meaningful and eventful phase of their lives.
Susan Crawley, a psychologist from Goldsmiths College in London, and author of the study to be published next year in the journal Memory, found that people aged 35 to 50 were much better at dating public events more accurately than those who were over 60.
"It is nothing to do with the pace of 20th century life," she said. "When you are younger you experience a lot more novel events than when you are older. People tend to remember more public events aged 15 to 35, the `reminiscence peak', because it is the time of life that lots of new important experiences happen, so they can relate public events to personal experiences."
The study involved 47 people who were asked to give the month and the year of 20 major public events, between January 1990 and December 1996, and 20, between January 1977 and 1989. Those in the 35 to 50-year-old age group were far more accurate in establishing the correct date. "Some of the events would have taken the 35 to 50 year olds into their reminiscence peak and so would have provided more personal landmarks to assist memory," said Ms Crawley.
The 60-year-olds were well beyond their reminiscence peak and so associated public events with personal events further back in time. "This may help to explain why the years appear to zoom by as you get older," she said.
HOW GOOD IS YOUR MEMORY?
1. When did Nelson Mandela become President of South Africa?
2. When did Iraq invade Kuwait to start the Gulf War?
3. When was John Lennon shot?
4. When was the Grand Hotel in Brighton bombed?
5. When was the Chernobyl disaster?