Otago study points to long-term recall of very early experiences

Most adults can’t recall events that took place before they were 3 or 4 years old—a phenomenon called childhood amnesia. While some people can remember what happened at an earlier age, the veracity of their memories is often questioned. Now, a new longitudinal study by University of Otago researchers has found that events experienced by children as young as 2 can be recalled after long delays.

The study, by Department of Psychology researchers, appears in the US journal Child Development.

To determine at what age our earliest memories occur, the researchers looked at around 50 Dunedin children and their parents. The research involved having the children play a unique game when they were 2- to 4-year-olds.

In the game, children placed a large object in a hole at the top of a “Magic Shrinking Machine” and turned a handle on the side. When a bell rang, a small but otherwise identical object was delivered through a door at the bottom of the machine.

Six years later, the researchers interviewed the children and their parents to determine how well they remembered playing the game.

Study lead author Dr Fiona Jack says that only about a fifth of the children recalled the event, including two children who were under 3 years old when they played the game. About half of the parents remembered the event. Parents and children who recalled the event provided very similar reports about the game.

“Although we couldn’t predict children’s long-term recall on the basis of their general memory and language skills, we found some evidence that talking about the event soon after it occurred may have helped preserve it in the memories of those who remembered it,” Dr Jack says.

“Our results are consistent with theories that suggest that basic capacity for remembering our own experiences may be in place by 2 years of age.

“The study has implications in clinical and legal settings, where it is often important to know how likely it is that a particular memory of an early experience is in fact genuine.”

The factors that determine whether a child will recall any particular event, however, remain elusive, she says.

Funding for the study was provided by Marsden Grants from the Royal Society of New Zealand, and the New Zealand Science and Technology Postdoctoral Fellowship Scheme.