In my couch, unable to sleep, I had nothing doing. Then I began to think about many things and everything, thinking forth and back. Reviewing past mistakes and planning ahead. Remembering past success, fun and smiling at myself. But something is not right, i can’t remember far back in childhood, i tried and tried but i could only remember image flashes of good moments. Why?
I want to believe that while playing one day, I probably fell and if not my arm, I broke my two front big teeth. The resulting pain, I unfortunately, can’t remember any of that now as an adult. If at all I do, the entire experience will be a dim memory captured in pictures.
And that’s because of a strange phenomenon known as childhood amnesia. Kids can remember events before the age of 3 when they are small, but by the time they are a bit older, those early autobiographical memories are lost. New research has put the starting point for amnesia at age 7.
Scientists have long wondered about the cause of this baffling memory-loss, and thought that language development might have something to do with it. But even rats and some other animals show a similar amnesia without language abilities.
Some Canadian researchers floated a possible cause: the precipitous growth of new cells in the hippocampus during infancy, known as neurogenesis. When brains are busy growing lots of new cells, they don’t store memories that would otherwise be long-term.
Whatever the mechanisms may be, when did the memories start being inaccessible?
In research published in the journal Memory, Patricia Bauer and her colleague Marina Larkina brought in groups of 3-year olds with a parent (typically a mother, as in most child development studies). The parent interviewed the child about events that had happened over the prior three months like a visit to a zoo or preschool, while the researchers videotaped.
Over the next 6 years, different groups of children came back at age 5, 6, 7, 8, or 9 to the lab and were questioned by the scientists on the events that happened when they were 3. Since the researchers knew the details of the events, they were able to probe exactly how much the kids remembered — and how they spoke about the memories.
If the kids were between 5 and 7 at the time of second interview, they remembered over 60% of events, but the children who were 8 and 9 remembered 40% or fewer of the events, and they had begun to talk about their memories in a different way.
Parents also have an effect on kids’ memories of events. Those who use an elaborative strategy with their little ones, asking lots of questions like “Tell me more” and “What happened?” and allowing the kids to guide the description, end up with kids that have earlier early and more robust memories.
“We think that it has to do with basic biological processes, as neural structures undergo a lot of postnatal development,” says Bauer. “Early in development those structures are working, but not very efficiently — children are forming memories, but through natural processes those are fading and becoming inaccessible. By the time you reach adulthood, those memories are working very effectively.”
The earliest memories tend to be ones filled with emotion, either positive or negative.
So it’s possible that I didn’t break my teeth or arm, or I might also have left it behind as I create new memories.