Theory of Mind (ToM) is the ability to understand that other people have thoughts that are different from our own. Acquiring this understanding of the mind is a crucial developmental milestone for children and allows them to succeed in environments such as school. Using their ToM, children can make predictions about another person’s behavior and understand why someone is happy or sad, even when they themselves feel the opposite way. Important research by our Co-founders Carlson and Zelazo 20 years ago showed that ToM depends a lot on children’s developing Executive Function skills: You need to be able to set aside your own perspective to appreciate someone else’s, and that requires self-control. ToM, along with Executive Function, is important for the successful implementation of any SEL program. The more we know about ToM, and what promotes it, the better we can create SEL-fostering activities.
ToM is often measured using something called the False Belief Task. Let’s take a look at an example to better understand what this task looks like in the diagram below.
Sally hides a toy in one place (the black box), and then she leaves the room. While Sally is gone, Ann moves the toy. Children are asked where Sally will look for her toy when she gets back.

Three-year-old children usually answer that Sally will look for her toy in the new hiding location (brown box). This could be because they know the toy is in the brown box, therefore, they assume that Sally knows what they know. With stronger Executive Function skills including working memory, impulse control, and mental flexibility, most 4- to 5-year-olds are able to successfully answer that Sally will look in the black box, suggesting they have acquired ToM. You can watch examples of this task being performed by several children in real life, here.
However, in a recent paper, Pesch, Semenov, & Carlson (2020) suggest that just passing this task might not be enough to say that children have achieved a fully mature ToM. Adding an additional box, among other changes to the traditional task, may place unique demands on a child’s Executive Function skills and their ability to correctly respond to ToM tasks. These findings suggest that ToM may depend on multiple factors and occurs over a longer period of time.
In the meantime, there are some things caregivers can do to support the development of children’s mentalizing abilities. By talking about their own thoughts, desires, and feelings, parents help develop the language required for ToM. Activities such as pretend play require more complex ways of thinking about situations and help children start to think about the existence of other people’s thoughts and desires. Finally, consistent play with supportive caregivers provides a context in which parents can bring awareness to their own and their child’s thoughts and desires. Like other developmental skills, ToM takes practice and a gradually increasing challenge level to develop.
About the Author:
Andrei Semenov is currently earning his Ph.D. in Developmental Psychology at the University of Minnesota, Institute of Child Development. His primary research interests are in how reflection and mindfulness training can help improve executive function skills. Currently, Andrei is working on a parenting program that promotes reflection and collaborative problem solving between parents and their children. Andrei has worked with the Earl E. Bakken Center for Spirituality and Healing where he helped develop and evaluate programs that promote mindfulness for teachers and educators. Andrei earned his B.A. in Psychology and Philosophy from the University of Colorado, Boulder where he studied how overscheduling children into extra-curricular activities may be associated with changes in their executive function skills. He has written and presented his work at academic conferences as well as in peer-reviewed academic journal