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There’s this story I’ve heard easily a thousand times. It’s my mom’s favorite story about me when I was little, and it involves these tiny toy cars called Micro Machines.

She says my Uncle Ahmad would bring me loads of these things — he got them from work.

“He worked at the Ford in Detroit, you were maybe a year and a half to 3 years old,” she recalls. “You used to love them, all the time you play with them, and you sit on the couch eating chips watching the highway, counting the cars on the highway, watching cars going and coming,”

According to my mom, I would have one of these tiny cars in my hand at all times.

“And you used to sleep with our friend Abbas,” she says. “He was visiting, and we had only a small apartment, so he would sleep in your room.”

Invariably, I’d wear myself out watching highway traffic, eating chips, and fall asleep with one of these toy cars in my hand. And every time I woke up, it would be gone. 3-year-old me demanded that Abbas had to help me look, in the middle of the night. As my mom tells it:

“You will wake him up at night. You want that car, that last was in your hand. If he doesn’t know which one, you throw it in his face and you keep telling him, ‘This is not it, this is not it.’”

I apparently expected Abbas to know which one I wanted without giving him any clues, no make or model.

“He would look at tons of cars, and keep giving you one after the other until you find the one you want, which we don’t know which one you want, only you know it,” she says laughing.

In this story, I have toys I liked, things I liked doing, I even have something like a personality — kind of a bratty one. But the thing is, I don’t remember any of this. My earliest memories don’t start until after kindergarten. When my mom tells these older stories, it’s weird, almost like she’s talking about a stranger.

That’s because of childhood amnesia. It’s something we all go through.

Emory University memory researcher Patricia Bauer has studied this type of forgetting for years. She tells me it baffled psychologists forever.

“They called it for many, many, many years the mystery of childhood amnesia,” Bauer says.

Sigmund Freud did some of the earliest thinking on this forgetting and called it the veil.

“The veil, which shields our earliest youth from us and makes us strangers to it,” Bauer says.

The Memory Veil

Freud didn’t understand the memory veil. In the early 20th century, no one did. And so it went until researchers finally had the bright idea of asking kids what they remembered.

“It’s so obvious, isn’t it? It’s so obvious,” Bauer says. “But yet we didn’t do it for years and years and years.”

Eighty years after Freud’s first writings, actually. For a long time, serious scientists didn’t think toddlers under 3 even formed memories, at least not the same way older kids and adults do.

“But as soon as we started examining it in childhood … we started to see that, yes, children form memories; yes, children retain them; and yes, they forget them just like adults, just a little bit faster,” Bauer says.

She and her team found 3-year-olds could recall something that happened, say, at 18 months. And they found if they asked again at ages between 5 and 7, most of the early stuff was still there. But then, after that, there’s a steep drop — by age 9, most of it is gone.

“Certainly, they didn’t forget everything from their past. They’re not just like a completely wiped clean slate,” she says. “You still have, of course, your memories of your family. You know where you live, you know a lot of information about yourself.”

But a lot of autobiographical memory — your life story — seems to evaporate. Bridget Callaghan is a researcher at UCLA focused on early memories.

“It’s not that children can’t learn and they can’t remember, it’s that they forget more rapidly,” she says. “And so those early memories that you encode end up getting lost over time.”

She works a lot with kids — and tells me about one study, in which children watch two adults interact with toys. The adults pretend one toy sucks and the other is awesome.

“They were toys we made ourselves. So there was one that was like a fish toy, and it made a really fun `boing’ noise, and there was one that was a monkey and it made a slightly different kind of noise,” Callaghan says.

She’ll see how kids interact with the toys weeks later —usually they remember the adults liked the fish toy, and that they avoided the lame monkey toy.

Eventually though, quicker than an adult would, they’ll forget the scene. But Callaghan thinks while we forget experiences, they’re not really gone.

“I think that our memories, and I’m speaking of memories whether we remember them or not, but these experiences that we have in our life that shape us and have an impact on us really do contribute [to] who we are, our personalities,” she says.

Forgotten, but not gone

Callaghan thinks early events can still encode themselves in us in unseen ways, leave footprints. You can see it in children who were abused or neglected when they were very young, — they may not remember that, but it still can make a distinct impact on brain structures, even affect gut bacteria.

And there’s the effect these events have on our internal logic.

“Memories, these early events that we have, they kind of shape our working models of the world,” Callaghan says. “The way that we understand [how] the world works and our place in it.”

Early events, like my family friend Abbas always fetching cars for me in the middle of the night, they can have profound effects on us.

“It sounds like whenever you wanted the toy car, he was there to give it to you, and that probably helped you set up this really reliable view of adults being helpful and someone that you could rely on,” she says.

Or, I don’t know, maybe Abbas is at least partially to blame for some toy store tantrum I threw years later.

So if all this early stuff is affecting who I am now, shaping me, how can it just be completely gone? Why can’t I remember any of it?

Callaghan thinks part of it has to do with language.

“When you incurred a memory, it’s kind of stuck in time, at least in terms of the language that you can use to describe it,” she says.

Basically, a toddler’s vocabulary is all I had to work with then.

“And as you kind of develop, you grow and your language becomes more complex, your concepts become more complex,” she says. “It actually becomes difficult for you to kind of retrieve those older memories that are stuck in time and difficult to update.”

And the other reason is, when you’re really little, your sense of self is still developing.

Robyn Fivush is another Emory researcher who focuses on early memories.

“So it’s not till about 20 months of age that that baby starts to show what’s called mirror self-recognition,” she says. “They recognize themselves in the mirror, which shows an awareness, they start to understand what they look like from somebody else’s perspective. That, ‘Oh, that’s what I look like. That’s me.’”

That’s step one of autobiographical memory.

“An autobiographical memory system is about me, not just about what happened, but what happened to me,” she says.

Basically, you need to recognize that you’re an individual person, separate from mom and the lamp, before you can start a life story.

And Fivush thinks step two has to do with story— the one we tell about ourselves. It’s why researchers think kids begin to really form autobiographical memories only in the preschool years.

“So what they learn over the course of the preschool years is, through language, to tell a fuller, more coherent story that reorganizes the memory to make it more complete and more organized,” she says. “And that makes it more durable.”

Fivush thinks the stories we tell are key to making memories stick — making them meaningful.

“That’s what we do as human beings, we search for meaning in the world, and stories are the way that we create meaning for ourselves, for other people,” she says.

A lot of Fivush’s research suggests that when parents reminisce often, retelling stories over and over, their children end up with earlier fuller memories.

“This is one thing we absolutely know about memory, right: the more you reinforce the memory, the better you remember it,” she says. “The more you rehearse it, the better you remember it.”

But if that’s the case, how does that explain the complete blanks I have before age 6 or 7? My mom, she tells “little Jad” stories all of the time.

Like the one about how it took me a super long time to understand the difference between cartoons and video games.

“You thought like you are watching TV, you didn’t know it’s a game,” she says. “After three years, you realize it’s a game and you can play.”

The first time she told me this story, she said it in Arabic, before I remind her our listeners won’t understand that.

I think it could be language at play again, in a slightly different way than Callaghan, the researcher from UCLA, is talking about.

For me, not only are my earliest memories stored in toddler language, they’re also in Arabic. That’s what my mom and I spoke. Even today, we usually mix Arabic and English on the phone.

I ask Callaghan: did all this scramble things more?

“I think that makes a lot of sense. I think it’s a really good hypothesis,” she says. “I think it’d be good to test.”

Toronto neuroscientist Paul Frankland, though, tells me language only explains part of the forgetting. As proof, he points to the guinea pig.

“At birth, they’re much more mature. They can walk, their eyes open soon after birth.” he says. “They can support their body weight and walk within a couple of days.”

They also can make and retain memories even as infants. A part of their brains, the hippocampus, is nearly fully developed in utero.

In humans, the hippocampus keeps maturing as infants and kids age. It’s also where many of our autobiographical memories are stored, in little constellations of neurons.

“Any one memory probably engages thousands and thousands of neurons,” he says. “But that still doesn’t… take up that much room,” he says.

When you forget something, Frankland thinks, that memory is still there, but the constellation is buried under a bunch of other stuff.

“They still exist in some form, but they are just extremely hard to access,” he says.

In mice, at least, you can shine a light on certain neuron constellations and the memories come back.

Barring that, we’re cut off from them. It’s actually part of a developmental give-and-take.

“The costs of adding new neurons is that you are going to destabilize stuff you’ve already stored in the brain, but the benefit down the line is that, you know, these new neurons are good for making new memories as well,” he said.

So the cost of remembering my 20s and 30s might be not remembering my 2s and 3s.

Guess my mom can go ahead and remember for me.