Childhood amnesia kicks in around age 7

You could travel the world with an infant aged under 3 and it's almost guaranteed that when they get older they won't remember a single boat trip, plane ride or sunset. This is thanks to a phenomenon, known as childhood or infantile amnesia, that means most of us lose all our earliest autobiographical memories. It's a psychological conundrum because when they are 3 or younger, kids are able to discuss autobiographical events from their past. So it's not that memories from before age 3 never existed, it's that they are subsequently forgotten.

Most of the research in this area has involved adults and children reminiscing about their earliest memories. For a new study Patricia Bauer and Marina Larkina have taken a different approach. They recorded mothers talking to their 3-year-olds about six past events, such as zoo visits or first day at pre-school. The researchers then re-established contact with the same families at different points in the future. Some of the children were quizzed again by a researcher when aged 5, others at age 6 or 7, 8 or 9. This way the researchers were able to chart differences in amounts of forgetting through childhood.

Bauer and Larkina uncovered a paradox – at ages 5 to 7, the children remembered over 60 per cent of the events they'd chatted about at age 3. However, their recall for these events was immature in the sense of containing few evaluative comments and few mentions of time and place. In contrast, children aged 8 and 9 recalled fewer than 40 per cent of the events they'd discussed at age 3, but those memories they did recall were more adult-like in their content. Bauer and Larkina said this suggests that adult-like remembering and forgetting develops at around age 7 or soon after. They also speculated that the immature form of recall seen at ages 5 to 7 could actually contribute to the forgetting of autobiographical memories – a process known as "retrieval-induced forgetting".

Another important finding was that the style mothers used when chatting with their 3-year-olds was associated with the level of remembering by those children later on. Specifically, mothers who used more "deflections", such as "Tell me more" and "What happened?" tended to have children who subsequently recalled more details of their earlier memories.

The researchers said their work "provides compelling evidence that accounts of childhood amnesia that focus only on changes in remembering cannot explain the phenomenon. The complementary processes involved in forgetting are also part of the explanation."

Further reading

Bauer PJ and Larkina M (2013). The onset of childhood amnesia in childhood: A prospective investigation of the course and determinants of forgetting of early-life events. Memory (Hove, England) PMID: 24236647