Psychologist Determine Age We Begin Forming Lasting Memories

Do you have trouble remembering your fifth birthday party, or your first day of school? This phenomenon, known as "childhood amnesia," has been shown by psychologists at Emory University to generally occur around age seven.

The study, published in the journal Memory, involved researchers interviewing children about events in their lives, beginning at age three. The children were then grouped into subsets and tested for recalling memories from ages five, six, seven, eight and nine.

"Our study is the first empirical demonstration of the onset of childhood amnesia," said Emory psychologist Patricia Bauer, who led the study. "We actually recorded the memories of children, and then we followed them into the future to track when they forgot these memories."

"Knowing how autobiographical memory develops is critically important to understanding ourselves as psychic beings," Bauer said, the study co-author and head of the Memory Development Lab, which focuses on how autobiographical memory changes throughout a person's lifetime. "Remembering yourself in the past is how you know who you are today."

Instead of interviewing adults about their childhood memories, as previous studies of childhood amnesia have done, the Emory researchers "documented early autobiographical memory formation, as well as the age of forgetting these memories," according to a release announcing the study.

The researchers recorded 83 children at the age of three being asked by their parents about six recent events in the child's life.

"We asked the parents to speak as they normally would to their children," Bauer said.

She gave a hypothetical example, "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 researchers then followed up with the children years later, by asking them to recall the same events that they recounted at the age of three. Each child returned once, either at age five, six, seven, eight or nine, to be questioned.

While the children between the ages of five and seven could recall 63 to 72 percent of the events, the children who were eight and nine years old remembered only about 35 percent of the events, writes the release.

"One surprising finding was that, although the five-and-six year-old children remembered a higher percentage of the events, their narratives of these events were less complete," Bauer said. "The older children remembered fewer events, but the ones they remembered had more detail."

Bauer said she believes this could be because memories with rich, vivid details tend to stick around longer. Older children have also developed better language skills, allowing them to better express memories.

Young children lack the strong neural processes required to compile all of the details used to form lasting autobiographical memories, she explained. "You have to learn to use a calendar and understand the days of the week and the seasons. You need to encode information about the physical location of the event. And you need development of a sense of self, an understanding that your perspective is different from that of someone else."