Theory of Mind and the Parent-Child Relationship

Most parents remember when their child lied to them for the first time. Initially, it often seems cute or amusing, but over time, it becomes seen as “bad behavior.” Lying is bad behavior, but it is also a developmental milestone for children that begins a sophisticated relationship process between them and their parents.  Around age 4, most children start to interpret and track the motivations, emotions, intentions, beliefs, and behaviors in other people’s minds. This capacity evolves through numerous interactions as they move into adulthood.  When your six-year-old says she can’t sleep without you in her bedroom because she’s afraid, she is responding to her picture of how you are likely to think and behave in response to her statement. Parents use their adult version of this ability when deciding how to tell their kids things they suspect they won’t want to hear, whether it be that the pet fish has died or it’s time to get off electronics.  This ability to “think about others’ thinking” is called the theory of mind (ToM).


The idea of ToM came out of the primatology field in studies of chimpanzees during the late 1970s. The central question concerned whether chimpanzees’ minds could represent the mental states, beliefs, and desires of other chimpanzees.  Studies tested this notion to clarify these same questions for human children in child psychology. 

In 1983, two cognitive neuroscientists devised a test to measure explicit ToM in children. The adjective “explicit” refers to the verbal proof of ToM that most children around three years can demonstrate. The test intends to show evidence of a child’s ToM by whether the child selects the correct answer to a question posed at the end of a scenario involving two people. The researchers gave this test to children from ages 3-9 years and found that at age 4, most of the children passed the test while most of the children three and under failed the test.

In 1985, Simon Baron-Cohen, Alan Leslie, and Uta Firth developed a version of this test that has become widely known and used called a “Salley Anne” test. The examiner shows a cartoon of two children, Sally and Anne.  Sally has a basket with a marble, and Anne has a box.  Sally takes the marble out of her basket, puts it in Anne’s box, and leaves.  While Sally is gone, Anne takes the marble from her box and returns it to Sally’s basket.  The question is then asked of the child:  “Where will Sally look for her marble?”  

That study gave this test to 27 children at least four years of age. The researchers concluded that those children answering that Sally would look in Anne’s box for her marble demonstrated ToM by showing they understood that Sally believed her marble would be where she last placed it. Therefore, these children showed they could predict where Sally would look based on what they thought she believed

After several replications, the findings were overwhelmingly consistent for neurotypical children. Neurotypical three-year-olds routinely failed the ToM test, while neurotypical four-year-olds mostly passed it. These findings helped establish ToM as a growing specialty across several professional fields that seek to understand better one of the psychological cornerstones of human development and social experience.

Thus, when children start lying to their parents, it can be understood as a sign that they are entering an essential developmental stage that allows them to develop a capacity that is fundamental in shaping how they see themselves and get along with others.  Lying is a misbehavior that enables parents to support children’s optimal relational, emotional, and social development and enrich their relationship with their child. 

Kids have built-in lie detectors, and they always have them trained on your mind. As a parent, these lie detectors can be a vehicle for increased psychological health.  Expressing what is on your mind transparently and responsibly can be challenging but helpful to everyone involved.  The following dialogue provides a brief glimpse of what a Mother who understands ToM can look like when interacting with her Child about lying.   

Ch:  What’s the matter, Mommy?

            M:   Mommy is angry right now, kiddo.  

            Ch: Are you angry at me, Mommy?

            M:   I’m not angry at you but what you did. That you lied to me about          

                   eating snacks in your room. 

            Ch: How did you know!?

            M:   I found Sun Chips wrappers under your bed.          

            Ch: I’m sorry, Mommy.

            M:  What are you sorry about, dear? 

            Ch: That you’re angry.

            M:   I can understand why you would be sorry about my feelings.  At the same time, my 

       anger is my business to deal with, and I will figure out how to manage that 

       myself.       

            Ch:   Okay.

Such interactions, which feature empathy and transparency about what is on one’s mind, fosters both the development of a child’s ToM and the parent-child relationship. Although not often discussed in helping fields or by the general public, ToM is pervasive in the human condition and familiar to most people’s experience.  Having it on your radar as a parent can be a valuable tool to make more sense out of ordinary, sophisticated, and sometimes bewildering family experiences and to help you better relate to your children and foster their growth.  

-Posted by Aron Carlson, LCSW-C

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