Scientists let toddlers play with a toy-dispensing vending machine. Here’s what they learned

A new study published in the journal Proceedings of the National Academy of Sciences reveals that children as young as two and three years old understand how possibility works, even before they know words like "impossible" and "unlikely". Researchers at the Johns Hopkins University Laboratory for Child Development sought to understand whether a child's experience of something "impossible" makes them more curious and quicker to learn, compared to rare events that are still within the realm of possibility.

The experiment involved showing 335 two and three-year-old children vending machine-like devices that dispensed a toy through a chute when a coin-like token was inserted. Some children experimented with a machine that contained a mix of pink and purple toys, while others had a machine filled only with purple toys. Each child received a small coin to put in the machine, which dispenses a toy randomly. This setup allowed researchers to observe children's responses to the colors of the toys based on their expectations.

In the first case, when a child sees toys of different colors, they expect to receive any toy of these colors. Receiving a pink toy is considered "possible" for the child because pink and purple are available in the machine. As long as getting a pink toy was possible, no matter how unlikely, the children experienced no boost to their learning. In contrast, in the case of children with a machine full of purple toys, some received a pink toy (it had been manipulated beforehand), which should not have been possible. If the child receives a pink toy from a machine containing only purple toys, it is considered an "impossible" event based on what they saw, and this requires children to reevaluate what they thought they knew.

After retrieving the toys, the children were told the name of the toy, which was an invented word, and were asked to remember it later. According to the findings, children who experienced the impossible scenario (receiving a pink toy from a machine with only purple toys) learned significantly better than everyone else. Children learn significantly better after experiencing what the researchers call "impossible situations", which stimulates their curiosity and makes them rethink what they know.

Professor Lisa Feigenson, co-director of the Johns Hopkins University Laboratory for Child Development and a co-author of the study, explains, "Young children already think in terms of possibilities." She also said, "Adults do this all the time and here we wanted to know whether even toddlers think about possible states of the world before they've had years of experience and before they have the language to describe these mental states." Furthermore, she added, "These results are so interesting because they show that when children see events in the world that they can’t explain, it instills in them a drive for information that they can use to reconcile their prior model of the world with what they’ve just seen." She concluded, "Scientifically, these findings are exciting because they suggest that humans are equipped from the get-go to think about whether things are possible or unlikely or just can't happen."

The authors believe that children learn much better after impossible events because the unexpected drives them to seek explanations. Impossible events force children to reevaluate what they thought they knew. In contrast, unlikely (but possible) events did not leave the same educational impact. Unlikely events can be surprising but do not necessarily require any explanation.

The research shows that the human ability to think about probabilities and reject what seems impossible begins from a young age, suggesting that humans are equipped from the beginning to think about whether things are possible or unlikely or simply cannot happen. The researchers say that children develop mental models about the world from a very early age. This reflects children's innate readiness to interpret the world in advanced ways.

The new findings conclude that parents and educators could create intensified learning moments by presenting mysterious situations that children cannot easily explain. The main goal of this experiment was to observe children's reactions to "impossible" events compared to rare but "possible" events. The study found that two and three-year-olds are able to distinguish between improbable and impossible events. It was previously unknown whether young children also engage in this kind of mental judgment about possibilities or if it develops with age and experience.

Children who encountered the impossible felt a strong desire to seek an explanation for what they had seen, which instills in them a thirst for information to reconcile their previous model of the world with what they have just seen. The experiment demonstrates that even young children think about the world in terms of possibilities, indicating that they are more sophisticated thinkers than previously understood.

Adults think about probabilities daily, such as whether it is likely to rain or if they will win a lottery ticket. It was previously unknown whether young children also engage in this kind of reasoning or if it develops with age and experience. The researchers say that children develop mental models about the world from a very early age. This reflects children's innate readiness to interpret the world in advanced ways.

The study's authors suggest that parents and educators could leverage these findings by creating learning opportunities that involve impossible scenarios. By presenting mysterious situations that children cannot easily explain, adults can stimulate children's curiosity and enhance their learning. The research indicates that impossible events require children to re-evaluate what they thought they knew, leading to significant learning and development.

Sources: Asharq News, Yahoo News, Primera Hora, Agencia SINC, The Independent

This article was written in collaboration with generative AI company Alchemiq