What do infants remember when they forget?

Six-month-old babies are severely limited in what they can remember about the objects they see in the world; if you hide several objects from an infant, they will only remember one of those objects with any detail. But a new study, which will be published in an upcoming issue of Psychological Science, a journal of the Association for Psychological Science, finds that when babies "forget" about an object, not all is lost.

Researchers used to think that babies less than two years old did not understand that an object continues to exist when it is not currently in the baby's view. But in the mid-1980s, new ways of doing experiments with babies found that they do, in fact, know that objects don't disappear when you're not looking at them—a concept known as object permanence. But it was still unknown what babies needed to remember about objects in order to remember their existence.

Now Melissa Kibbe, of Johns Hopkins University, and Alan Leslie, of Rutgers University, are working to figure out exactly what it is that babies remember about objects. For the new study, they showed six-month-old babies two objects, a disk and a triangle. Then they hid the objects behind small screens, first one shape, then the other. Earlier research has shown that young babies can remember what was hidden most recently, but have more trouble the first object that was hidden. Once the shapes were hidden, they lifted the screen in front of the first object. Sometimes they showed infants the shape that was hidden there originally, but sometimes it was the other shape, and sometimes the object had vanished completely.

Psychologists measure how long babies look at something to see how surprised they are. In Kibbe and Leslie's study, babies weren't particularly surprised to see that the shape hidden behind the screen had changed, for example, from a triangle to a disk. But if the object was gone altogether, the looked significantly longer, indicating surprise at an unexpected outcome. "This shows that even though infants don't remember the shape of the object, they know that it should continue to exist," Kibbe says. "They remember the object without remembering the features that identify that object."

This helps explain how the young brain processes information about objects, Leslie says. He suspects the brain has a mechanism that acts like a kind of pointer, a mental finger that points at an object. Each finger can only point to one object. "Just like a finger that points to something, you can't tell from the finger itself what the shape of the thing being pointed at is," Leslie says. "You can't tell from looking at my finger whether I'm pointing at a cat or a dog." This study shows that the mechanism in the baby's brain that remembers the object doesn't have to remember much about it.

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CHollman82
5 / 5 (3) Sep 27, 2011
"Researchers used to think that babies less than two years old did not understand that an object continues to exist when it is not currently in the baby's view"

Are you kidding me? Were none of those researchers parents?

My one year old absolutely understands this, and has for at least several months. He will drop something over the back of the couch, get down and go around to the back of the couch and get it. He will throw a ball and if it goes around a corner out of sight he will go around the corner and get it... there are many other examples. The point is, possibly as early as 7-8 months, he understood that things that went out of sight did not cease to exist... around the 8 month mark he would drop things from his high chair and look over the edge at them on the floor...
DKA
5 / 5 (2) Sep 27, 2011
my daughter was about 1 year old. She saw a program with a tiger in it. Then she remembered that she was onced offererd a tiger like teddy bear some time before. She toughts it was in the bedroom, so she ran to look for it in that room. When she found it, she came back and showed it to us.
I am 100% sure she is able to remember about objects not in her sight since she was months old and even before that.
We teached her signed language and when she was 5 years old, she was already telling us more then we expected, she knew she wanted to "play" or that she was going to go get a specific toy in order to "play".

StarGazer2011
5 / 5 (1) Sep 27, 2011
CHolliman : Its pretty obvious to most parents that most researchers have absolutely no idea what they are talking about.
hush1
not rated yet Sep 28, 2011
lol
It only takes Melissa and Alex (the authors) and parents here the time to remember their own first peek-a-boos.
And I will be honest. I can not remember my first peek-a-boo.
I blame my twin for this.

My child (at six weeks) and I started this mind blowing experience. I have not asked him what he remembers. He is busy with theoretical physics now.

I tried to "spoil" our newborn with attention (24/7).
This is not possible with newborns. Newborns can not overdose on attention. I tried in vain. Instead he adapted our schedule in two weeks.

To this day the original primordial peek-a-boos startled all humans: "you startled me!" Somehow, over time, a neuronal pathway of association of fear latched on to the original peek-a-boo of surprise association.
I've looked in vain for first peek-a-boos associated with fear instead of surprise.
Isaacsname
not rated yet Sep 29, 2011
" Researchers used to think that babies less than two years old did not understand that an object continues to exist when it is not currently in the baby's view. "

Wouldn't that imply that infants forget their parents exist when they leave the room ? I'm not buying it.
hush1
not rated yet Sep 30, 2011
Object permanence is reinforced through repetition.
Repetition can only occur if the object has "now-you-see-it-now-you-don't".

The surprise is a permanence of nothing - no object.
Going against anyone's senses at any stage of life.

"This shows that even though infants don't remember the shape of the object, they know that it should continue to exist"

Incorrect presumptuous conclusion.
This shows that even though infants don't remember any object or shape, they 'know' whatever and however they label 'it', it should REPEAT.

They remember ANYTHING REPEATS without remembering any features about anything that identifies any object.

No one knows what 'existence' is. Not even the greatest minds.
Of course scientists expect more of babys than greatest minds.

"This study shows that the mechanism in the baby's brain that remembers the object doesn't have to remember much about it."

What is repeated becomes remembered - no surprise. Nothing, when that happens, is a surprise.