Insight Into Toddlers’ Awareness of Their Own Uncertainty

Summary: When it comes to decision making, researchers discovered toddlers experience and deal with uncertainty in the same way as older children and adults.

Source: UC Davis

Toddlers may not be able to describe their feelings of uncertainty, but a new study from the Center for Mind and Brain at the University of California, Davis, provides evidence that toddlers may experience and deal with uncertainty in decision making in the same way as older children and adults.

“Little children show behaviors that suggest they can respond to uncertain situations. For example, they seem to hesitate or ask when they can’t figure something out,” said Simona Ghetti, professor of psychology at UC Davis. “But are these behaviors grounded in their evaluations of actual evidence? And how do very young children become aware they are uncertain?”

The new study, involving 160 toddlers from 25 to 32 months old, provides a window into how young children’s minds work as they perform a task, she said. The work is published July 20 in Nature Human Behaviour.

First author Sarah Leckey, graduate student in the Center for Mind and Brain, led the experimental work. In the study, 2-year-olds were shown pairs of images of animals or common objects, each mostly obscured by a gray square. They were asked to find one of the objects, for example “where is the elephant hiding?”

The task was carried out with both an eye-tracking device, where toddlers responded by pointing, and a touch screen, which allowed to collect their response speed. The experiment was conducted twice, with two groups of 80 children, to ensure reproducibility of the results.

Tracking gaze and behavior

By following the children’s gaze with eye tracking and measuring how long it took them to come to decision, the researchers could see how the children gathered information before making a decision.

“We can look at behavior like how they are distributing their looks to find useful information, how they go back and forth between images, or whether they take extra time before responding,” Leckey said.

This shows a toddler
Small children may not be able to describe feelings of uncertainty in decision making, but new research from the UC Davis Center for Mind and Brain provides evidence that toddlers experience and deal with uncertainty in the same way as older children and adults. Image is credited to UC Davis.

Children spent longer deliberating on more difficult trials, when the images were more similar, and when they came to an incorrect decision. The researchers were able to further analyze the data using a type of model called a drift-diffusion model, never previously used in studies of such young children.

“We can see if they act as if they are more or less confident,” Leckey said. Ghetti believes that toddlers’ responses to difficult decisions and their search for more information become the basis for eventually becoming aware of our uncertainty, which is fundamental to how we learn as older children and adults.

Additional authors are Diana Selmeczy, Alireza Kazemi, Elliott G. Johnson and Emily Hembacher. The work was supported by a grant from the National Science Foundation.

About this learning research article

UC Davis
Media Contacts:
Simona Ghetti – UC Davis
Image Source:
The image is credited to UC Davis.

Original Research: Closed access
“Response latencies and eye gaze provide insight on how toddlers gather evidence under uncertainty”. by Sarah Leckey, Diana Selmeczy, Alireza Kazemi, Elliott G. Johnson, Emily Hembacher & Simona Ghetti. Nature Human Behavior.


Response latencies and eye gaze provide insight on how toddlers gather evidence under uncertainty

Toddlers exhibit behaviours that suggest judicious responses to states of uncertainty (for example, turning to adults for help), but little is known about the informational basis of these behaviours. Across two experiments, of which experiment 2 was a preregistered replication, 160 toddlers (aged 25 to 32 months) identified a target from two partially occluded similar (for example, elephant versus bear) or dissimilar (for example, elephant versus broccoli) images. Accuracy was lower for the similar trials than for the dissimilar trials. By fitting drift–diffusion models to response times, we found that toddlers accumulated evidence more slowly but required less evidence for similar trials compared with dissimilar trials. By analysing eye movements, we found that toddlers took longer to settle on the selected image during inaccurate trials and switched their gaze between response options more frequently during inaccurate trials and accurately identified similar items. Exploratory analyses revealed that the evidence-accumulation parameter correlated positively with the use of uncertainty language. Overall, these findings inform theories on the emergence of evidence accumulation under uncertainty.

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