What's your earliest memory? Most adults struggle to remember anything from before the age of three and scientists have now identified when we forget our first memories.
A new study into "childhood amnesia" - a term coined by Sigmund Freud to describe this loss of memories from our early years - has found that it begins to set in at the age of seven.
The study found that most three-year-olds can recall events that have happened over a year earlier and most five to seven-year-olds could remember up to 72 per cent of their experiences from the first three years of their life.
But by the age of seven children's early memories begin to decline rapidly. Most eight and nine-year-olds can only remember about 35 percent of their experiences before the age of three.
Instead of relying on interviews with adults, as previous studies of childhood amnesia have done, the research from Emory University involved interviewing children about past events in their lives.
According to the researchers, young children tend to forget events more rapidly than adults do because they haven't yet developed the sophisticated mental processes required to give memories a sense of time or place.
"You have to learn to use a calendar and understand the days of the week and the seasons," explains psychologist Patricia Bauer, who led the study. "You need to encode information about the physical location of the event.
"Memories are like orzo and young children's brains are like colanders with large holes trying to retain these little pieces of memory. As the water rushes out, so do many of the grains of orzo. Adults, however, use a fine net instead of a colander."
Bauer's research also uncovered some interesting findings about how to help children preserve their earliest memories.
The experiment began by recording children at the age of three, while their mother or father asked them about events that the child had experienced in recent months, such as a trip to the zoo or a birthday party.
"We asked the parents to speak as they normally would to their children," Bauer says. "The mother might ask, 'Remember when we went to Chuck E. Cheese's for your birthday party?' She might add, 'You had pizza, didn't you?'"
"The child might start recounting details of the Chuck E. Cheese experience or divert the conversation by saying something like, 'Zoo!'
"Some mothers might keep asking about the pizza, while another mother might say, 'Okay, we went to the zoo, too. Tell me about that.'
Parents who followed a child's lead in these conversations tended to elicit richer memories from their three-year-olds and, according to Bauer, this approach also related to the children having a better memory of the event at a later age.
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