Scientists peer inside the infant mind
In a long-term effort to 'reverse-engineer' infant cognition, researchers have shown how babies are able to preform sophisticated analyses of how the physical and social world around them should behave. Greg Dash reports.
CARDIFF: In a long-term effort to ‘reverse-engineer’ infant cognition, researchers have shown how babies are able to preform sophisticated analyses of how the physical and social world around them should behave.
The study identified that infants are able to take multiple sources of information presented to them and make reasoned judgements on the probability of events.
The researchers said the babies are using “pure reasoning,” which involves combining different sources of information, guided by abstract knowledge, to make predictions about events they’ve never directly experienced.
“We basically taught infants to play lotto, but with a twist,” said co-author Luca Bonatt of Pompeu Fabra University in Catalonia, Spain, of the paper in the current issue of Science. “We showed that infants can compile multiple sources of information in an optimal way, without [the] need of extensive training or previous experience.”
Inside the infant mind
In the past 30 years, scientists have shown that infants have a solid grasp on the basic rules of the physical world. They understand that objects can’t wink in and out of existence, and that objects can’t ‘teleport’ from one spot to another.
More recently infants have been shown to understand basic notions of statistics and form beliefs about what future events are more or less likely to happen, even if they have not experienced such events before.
The study is the first step in a long-term effort to ‘reverse-engineer’ infant cognition by studying babies at ages three-, six- and 12-months-old to map out what they know about the physical and social world.
Lotto with a twist
Scientists at the Massachusetts Institute of Technology (MIT) developed a computational model of infant cognition that can accurately predict infants’ surprise at events that violate their conception of the physical world, calculating the probability of a particular event, given what is already known about the objects involved.
Teaming up with an international team of researchers co-led by MIT’s Josh Tenenbaum, the MIT scientists found that infants can use knowledge to form surprisingly sophisticated expectations of how novel situations will unfold.
Infants were shown a container in which different objects bounced for a certain period, before one of them exited. In one example, 12-month-olds were shown four objects – three blue, one red – bouncing around a container. After some time, the scene would be covered, and during that time, one of the objects would exit the container through an opening.
If the scene was blocked very briefly (0.04 seconds), infants would be surprised if one of the objects farthest from the exit had left the container. If the scene was obscured for longer (two seconds), the distance from exit became less important and they were surprised only if the rare (red) object exited first. At intermediate times, both distance to the exit and number of objects mattered.
“Babies, from the time they’re still in the womb, are already learning. By the time humans are born, we already have all our neurons in place.”
Modelling infant cognition
A computational model developed by the researchers, known as the ‘ideal-observer model’, accurately predicted how long babies would look at the same exit event under a dozen different scenarios, varying number of objects, spatial position and time delay.
This marks the first time that infant cognition has been modelled with such quantitative precision, and suggests that infants reason by mentally simulating possible scenarios and figuring out which outcome is most likely, based on a few physical principles.
“The research showed that infants are able to adapt their reasoning to changing situations,” said Bonnatti.
“In this sense, we showed that they are very good reasoners in such situations, which are simple but already contain many sources of information that must be appropriately evaluated and integrated to give rational responses”.
“One thing this research brings is in the UK, as well as in the U.S., parents, caregivers and health carers who deal with infants and children do not necessarily realise how smart these babies are – how ‘adult’ in a sense they are,” said Claudia Uller, director of the Infant Cognition Lab at the University of Cambridge, who was not involved in the study.
“Babies, from the time they’re still in the womb, are already learning. By the time humans are born, we already have all our neurons in place. We don’t grow neurons after birth – connections proliferate and develop, and loads of them die and disappear,” she added.
“In a nutshell, would it be unreasonable to hypothesise, given that we’re born with our brains in place, that we’re born smart enough to figure out the physical world instantly? This includes having a ‘computer’ in place from the start that is clever enough to make rational inferences in novel situations via the analysis, computation and integration of previous observations, given abstract knowledge,” said Uller.