New findings from a study conducted by psychologists at the University of Colorado at Boulder and the University of South Carolina could change scientists' basic understanding of how infants learn.
The findings suggest that infants' understanding of concepts like "object permanence," the idea that an object still exists even if they can't see it, may be learned rather than innate, according to Yuko Munakata, a CU-Boulder psychology professor. Munakata and psychology Professor Jeanne Shinskey of the University of South Carolina conducted the research in Munakata's Cognitive Development Center at CU-Boulder.
A paper on the subject appears in the August edition of the journal Psychological Science.
"Our findings may challenge the notion that infants have a general object permanence concept that applies to all objects, and that this may be present from birth," Munakata said. "Instead, we think infants' developing understanding of objects may be tied more closely to their experiences with specific objects in their environments."
The findings may be significant for understanding the origins of human knowledge and how knowledge changes over time, according to Munakata. It also may lead researchers to look more closely at the role of learning, even for fairly basic concepts about the world, and the specificity of early knowledge.
Their findings also suggest that what infants appear to know depends heavily on how they are tested.
In an effort to answer questions about how infants gain knowledge, Munakata and Shinskey looked at one aspect of cognitive development that scientists continue to grapple with -- infants' understanding of the concept of object permanence.
In the first demonstration of its kind, they showed that infants reached more often for familiar objects than novel ones when the objects were hidden, despite their normal preference to reach for novel items.
To conduct their study, Munakata and Shinskey presented 7.5-month-old infants with one object repeatedly until they were bored with it. They then presented them with this object and with novel objects, in the light and in the dark, and measured how often they reached for each object.
Researchers have long thought that infants prefer novel items to familiar ones when both are presented to them, according to Munakata. If you show an infant two items, one he or she has seen, and a new one, he or she will look at or reach for the new one.
"If you want to learn about the world, you are going to seek out new things," Munakata said. Once infants have mastered all the information one stimulus has to offer, checking out new ones is an adaptive strategy for acquiring large amounts of information in a short time, she said.
Munakata and Shinskey also were interested in finding out why infants seem to understand object permanence within the first few months of life when tested with one measure, but not until several months later when tested a different way.
"Kids can seem really smart when you test them a certain way, but totally oblivious when tested another way," Munakata said.
She believes this is because infants gradually develop stronger mental representations of objects through experience, with stronger representations required for some tasks than for others. There is some understanding of the concept at 2 months old and more at 8 or 9 months.
"Our idea is that knowledge is graded, rather than all or nothing," Munakata said. "Infants can know things to different degrees, which includes infants as young as 2 months old having some knowledge of hidden objects."
Munakata's research team in the Cognitive Development Center includes 12 undergraduate students. They work with infants as young as 6 months old and children up to 6 years old.