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Symbols Can Help Children Control Impulses, Get More Of What They Want

September 8, 2005
University of Washington
Researchers investigating how self- control develops in young children found that abstract symbols can lead the youngsters toward a more optimal decision than when they have to make a choice with tangible objects such as candy.

Sometimes less is more.

That is a difficult concept to grasp, particularly when you are a3-year-old. But psychologists have discovered something that helps --symbols.

Researchers investigating how self-control develops inchildren found that abstract symbols can lead the youngsters toward amore optimal decision than when they have to make a choice withtangible objects such as candy.

This was demonstrated when the researchers gave 3-year-oldsthe choice of a tray with two pieces of candy or one with five. Evenwhen told that the tray they picked would be given away, most of theyoungsters still picked the tray with the most candies.

However, when abstract symbols, such as dots or animalpictures were used to represent the candy, many of the 3-year-oldscaught on and chose the symbol representing the smaller amount ofcandy, leading to the larger reward.

"Many 3-year-olds are compelled to point to larger rewardseven though in this game that means they will get a smaller reward.When you remove the real reward and substitute it with symbols, itenables children to control their response," said Stephanie Carlson, aUniversity of Washington associate professor of psychology and leadauthor of a new study appearing in the current issue of the journalPsychological Science.

"When children get stuck on a problem, using symbols can helpthem solve it. For example, if you are trying to get kids to wait for amarshmallow as a reward it is helpful to get them to think about thereward in a different way -- such as thinking of the marshmallow as afluffy cloud to help them delay gratification. Many parents, however,tend to do the opposite. They say, 'you can't have it now, but justthink about how good it will taste when you can.' This increases thetemptation instead of shifting their attention," she said.

Carlson, who is studying executive functioning, or howchildren develop the ability to control their thoughts and actions, setup two experiments.

The first showed that this ability is directly related to ageand verbal ability. In the experiment, 101 typically developing 3- and4-year-olds had to make the choice between the trays containing eithersmaller or larger amounts of candy (jellybeans or chocolate chips). Anexperimenter explained the rules, and showed each child that when theypointed to a tray the candy would go to a toy monkey and the childwould get the contents on the other tray. Each child was given 16 testtrials, with candy being replaced on the trays after each trial.

Four-year-olds significantly outperformed the 3-year-olds,although some of the 3-year-olds with high verbal ability scored well.The 3-year-olds did not improve over the course of the trials while4-year-olds showed significant learning.

"Three-year-olds tended to be inflexible and didn't seem toimprove with the feedback of seeing the toy monkey getting moretreats," said Carlson. "But 4-year-olds changed strategies and appearedto learn from feedback without any explicit instruction."

In the second experiment, the researchers tested 128 typicallydeveloping 3-year-olds. The children were randomly assigned to one offour conditions -- real treats, rocks, dots and one called mouse vs.elephant. In this experiment, two boxes with drawers containing two orfive candies replaced the trays. In the first two conditions, a numberof the candy or rocks corresponding to candy inside the drawers wereplaced on top of the boxes. In the dot condition pictures with a smallor large number of dots were placed atop the boxes. In the mouse vs.elephant condition pictures of those animals were placed on the boxesand the children also were shown a stuffed toy mouse and elephant andtold they had a small or large stomach that could hold a few or a lotof candies. In each case the researchers made sure the childrenunderstood that what was on top of each box corresponded to the two orfive candies inside the drawers.

Then, as in the first experiment, the children were told topick one of the two boxes, with candies inside the one they chose goingto a toy monkey. Each child was given 16 trials.

There were significant performance differences depending onwhat was on top of the boxes. With the candies and the rocks, most ofthe children continued to pick the boxes with the larger amounts ontop, just as the 3-year-olds in the first experiment did. But in thedots and mouse vs. elephant conditions, the children picked the boxesrepresenting the smaller amount of candy significantly more often. Andtheir performance was strongest in the most abstract conditions, mousevs. elephant.

Carlson said the substitution of the real reward with symbolsallowed the children to control their responses. Faced with the rockchoice they "were compelled to pick the large number because the rockshad a one-to-one correspondence with the real treat." She said with thedots there was no resemblance to the treats, just lots or less dots,and amounts were totally eliminated in the choice between the mouse andelephant. The 3-year-olds performance on the mouse vs. elephant choicematched the performance of the 4-year-olds in the first experiment.

There were no differences in the performance by boys and girls in the two experiments.

Carlson said a big jump in children's self-control typicallyoccurs between 3 and 4, along with other major related developmentalchanges such as the ability to understand another person's perspectiveand to engage in elaborate pretend play.


Co-authors of the paperwere Angela Davis, a UW psychology doctoral student, and Jamie Leach, aformer UW psychology undergraduate student who is now a doctoralstudent at Stanford University. The National Institute of Child Healthand Human Development funded the study.

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University of Washington. "Symbols Can Help Children Control Impulses, Get More Of What They Want." ScienceDaily. ScienceDaily, 8 September 2005. <>.
University of Washington. (2005, September 8). Symbols Can Help Children Control Impulses, Get More Of What They Want. ScienceDaily. Retrieved May 23, 2017 from
University of Washington. "Symbols Can Help Children Control Impulses, Get More Of What They Want." ScienceDaily. (accessed May 23, 2017).