Theory of Mind (A complete guide)

Theory of mind is the capacity to comprehend the mental states of others and to perceive that those mental states may differ from our own.

Developing theory of mind is a key phase of child development.

Testing Theory of Mind 

Psychologists regularly evaluate a child’s developing theory of mind by playing out the “hide-and-seek deception task”.

In the most widely recognized form of this experiment, the psychologist will request that the child watch two actors: Sally and Anne.

The principal actor, Sally, puts a marble in a basket and leaves the room. When Sally leaves, Anne moves Sally’s marble from the basket into a box.

The Psychologist at that point asks the child, “Where will Sally look for her marble when she returns?” 

A child with a well-developed theory of mind will respond that Sally will look for her marble in the basket.

Despite the fact that the child knows the marble is no longer in the basket, he or she recognizes that Sally did not see Anne move her marble, and therefore understands that Sally will look for her marble in the basket–where she originally placed it.

Children who lack theory of mind will watch the same demonstration and conclude that Sally will look for her marble in the box.

This reaction illustrates that the child cannot understand that Sally has not seen what the child has seen, and does not have the same knowledge.

The Development of Theory of Mind

During typical child development, children will start to answer false belief questions correctly around age 4 (i.e. the child in the example above who correctly states that Sally will look for her marble in its original location).

In one meta-study, scientists found that children under age 3, as a rule, answer false belief questions incorrectly, 3-and-a-half-year-olds answer correctly roughly half the time, and the extent of right reactions keeps on expanding with age. 

Significantly, theory of mind skills are not “all or nothing.”

An individual may comprehend others’ psychological states in certain circumstances, yet struggle with more nuanced situations.

For instance, somebody could easily pass the false beliefs assessment yet at the same time have difficulty understanding non-literal communication such as sarcasm, analogies, and non-verbal cues.

One way to test a person’s theory of mind is to ask them to evaluate emotional states based on photos of peoples’ eyes. 

The Role of Language 

Research suggests that our use of language plays a role in the development of theory of mind.

In an experiment to test this hypothesis, researchers studied a sample of Nicaraguan people who were hard of hearing– the sample included participants who had varying degrees of education/diverse introductions to gesture-based communication.

The experiment found that participants that developed gesture-based communication in a less consistent and predictable way would generally answer false belief questions incorrectly, while those participants who had acquired more complete and complex gesture-based language would generally answer correctly.

However, when the group of participants with less advanced knowledge of gesture-based communication were taught words/gestures associated with emotional states, they were more likely to begin answering the false belief questions correctly.

Some research even shows that children can acquire some understanding of theory of mind before they can talk.

In one study, researchers observed eye movements of children while answering a false belief question.

Results showed that even when a child answered the false belief question incorrectly, they had enough comprehension to look at the correct object/response.

Using the original example of Sally and Anne, even when a child said that Sally would look in the box for her marble (incorrect answer), his or her eyes would be looking at the basket while responding (correct answer).

The results of this research give support to the hypothesis that some concepts of theory of mind develop even before language.

Theory of Mind and Autism Spectrum Disorder

There is a lot of research to suggest that people with Autism Spectrum Disorder (ASD) lack typical theory of mind skills.

Researchers Simon Baron-Cohen and Uta Frith conducted false-belief experiments with children with ASD and found that the participants overwhelmingly failed the test.

Though ultimately no direct causal relationship has been proven, there does seem to be a strong correlation between ASD and under-developed theory of mind.

One of the defining features of Autism Spectrum Disorder is difficulty in social interactions.

Individuals with ASD often struggle to pick up on non-verbal communication and very rarely understand non-literal language.

Baron-Cohen and his colleagues theorized that this recurring trait within children with ASD was caused by/correlated with their inability to develop appropriate theory of mind.

It is important to distinguish that while some people with ASD can successfully pass the false-belief test, the lack of theory of mind appears to be more universal.

Certain theory of mind skills, such as gauging expectations and reactions to moral reasoning, are especially difficult for individuals with ASD to comprehend. 

Research has shown that the development of language is uniquely impactful when it comes to theory of mind.

As mentioned above, studies find that people are more likely to develop higher levels of theory of mind if they are taught language to describe mental and emotional states.

One possible symptom of ASD is delayed or undeveloped speech and language.

Based on the concept that language development influences theory of mind, it is easy to see the connection between ASD and theory of mind.

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What is Theory of Mind and how does it form?

Theory of Mind is the comprehension that other people do not share the same thoughts, feelings, and experiences as oneself.

It develops in infancy and early childhood as children observe and imitate social behaviors and begin to consider the thoughts and feelings of the people around them.

At what age does Theory of Mind develop and what is an example?

Though children start to notice and mimic social behaviors during the first three years of life, Theory of Mind truly begins to develop between ages four to five.

For example, by age four, most children can understand that other people may hold false or incorrect beliefs about objects, people, or situations.

Who discovered Theory of Mind?

The term “theory of mind” was first coined by David Premack, an American psychologist who studied the concept by experimenting on a chimpanzee named Sarah.

Can Theory of Mind be taught?

There is much research on the topic of theory of mind “training,” which includes any form of instruction which is designed to teach people how to recognize mental states.

However, many in the field also believe that the skills can be taught in specific situations, but the person may not be able to transfer those skills to other, similar situations.

Why is Theory of Mind important?

Developing a theory of mind is critical for us to understand ourselves and others.

It fosters self awareness, wherein we can reflect upon our own thoughts, beliefs, and behaviors.

Theory of mind also allows us to reflect upon and understand the mental states of other people– an ability that is essential in social interactions and forming relationships.

How does Theory of Mind help in the development of social relationships?

Theory of mind gives us insight into other peoples’ heads– we can infer their intentions, hopes, fears, beliefs, and expectations.

Having the ability to form accurate ideas about what other people are thinking allows us to respond appropriately and accordingly.

Without skills of theory of mind, social interactions will be fraught with misunderstanding.

If you want to know more about theory of mind, check out these recommended reads:

Theory of Mind: Beyond the Preschool Years by Scott A. Miller

Miller provides a comprehensive review of the literature on theory of mind after the preschool years, and compares the early research with more current research on social understanding.

Mindblindness: An Essay on Autism and Theory of Mind by Simon Baron-Cohen

In this book, Simon Baron-Cohen presents his model and extensive research on the concept of theory of mind in children on the Autism Spectrum.

Theory of Mind: How Children Understand Others’ Thoughts and Feelings by Martin J. Doherty

This book is a concise and readable review of the extensive research into children’s understanding of what other people think and feel, a central topic in developmental psychology known as “Theory of Mind.”

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