Empathy, tolerance and the ability to see the world from others' perspectives are crucial skills -- and they begin developing early in life. New research suggests that playing with dolls rather than tablets may be more effective at fostering these abilities.

Researchers from Cardiff University in the UK found that children ages 4-8 who played with dolls showed better improvement than those who played open-ended games on digital tablets in developing what is called "false-belief understanding." The study was a randomized trial and was conducted over six weeks.

False-belief understanding is our ability to recognize that others can hold false beliefs or be mistaken about the world. Developing this cognitive skill helps us appreciate that others can have different beliefs and opinions -- about politics, religion, among many things -- and be able to tolerate and empathize with that. 

Children who develop this cognitive ability can better navigate increasingly complex social situations and deal with conflicts. Psychologists believe that kids begin to develop this ability primarily between ages 4 and 8, and some studies have shown that development can start even before age 2.

The classic example of false-belief understanding is the Sally Anne task, conducted by researchers in London in 1983. Children were shown two dolls -- Sally, who had a basket, and Anne, who had a box. The Sally doll then puts a marble in her basket and leaves the room. Anne takes the marble from the basket and hides it in her box. Sally then returns to the room.

The children in the study were asked three questions, the main one being, "Where will Sally look for her marble?" If the kids answered "the basket," then they understood that Sally's view of the world -- that the marble was still in her basket -- did not reflect reality.

The experiment

For the six-week trial, children ages 4-8 played with either dolls or digital tablets loaded with creative, open-ended games. There were 81 children, with an average age of 6, from South Wales. The kids were randomly selected to play with either dolls or tablets; they could not choose on their own. The parents kept diaries of the play sessions, which lasted hours.

After the trial period, researchers found that the children who had played with dolls had a stronger improvement in false-belief understanding and an ability to separate their knowledge from what others believed to be true. To measure this improvement, the researchers used the Sandbox Task, a psychological tool created in 2011. It's similar to the Sally Anne task but involves relocating and burying an item in a sandbox.

The researchers also saw that the children in the doll group often included friends, siblings and parents in their play. The children in the tablet group mostly played alone. The children who played with dolls also often gave them personalities, talking about what they thought the dolls wanted, believed or felt.

The researchers concluded that playing with dolls might help children practice and improve social-processing skills.

"The mechanism underlying this improvement requires further investigation, but we speculate that dolls may encourage social interaction and further practice of these skills outside of social interactions," according to the study.

Tablet use is widespread among kids

Busy parents may be tempted to use tablets to keep their children occupied. The Pew Research Center found that 63% of children ages 2-4 interacted with tablets, and that number rose with age -- 81% in children ages 5-7 and 80% in children ages 8-10. The research also showed the majority of children used smartphones at young ages -- 59% in ages 2-4, 58% in ages 5-7 and 64% in ages 8-10.

A majority of parents -- nearly 60% -- said they were "doing the best they can," while a little more than 40% said they "could be doing better" at managing their kids' screen time, according to the study.

Are tablets bad?

So, is it time to ditch the tablets and order some dolls? Sarah Gerson, co-author of the study and a developmental psychologist at Cardiff University, said the study isn't an indictment of children using tablets or other devices.

"My general advice is about letting children embrace the kinds of play that they find most natural," Gerson told CNET. "Although tablet games were our 'control'/comparison group in this study, we make a point of saying this doesn't mean anything negative about tech. Instead, different types of toys and play can be beneficial for different kinds of learning/development."

Although Gerson and her team used dolls in the experiment, children might also improve their understanding of false beliefs through play with other inanimate objects.

"Humanoid dolls are an easy access point in that it naturally propels children to use them to practice social interactions," Gerson said. "There's likely a lot of variability in which children extend these kinds of social interactions to stuffed animals, dinosaurs, superheroes, etc. What I think is interesting about dolls is that they don't necessarily have a prescribed role or script -- unlike, say, superheroes -- so it allows children to play however they'd like in open-ended ways."