Written by Brett Weiss
July 2019
Our social lives depend upon theory of mind, defined as attributing thoughts, intentions, and beliefs to others. We develop our theory of mind to predict future actions of others based on our past experiences with those individuals. Interestingly, when we have little acquired data on the behavior of people we are unfamiliar with, we often attribute our own behavioral preferences to them based on the environmental context (Koster-Hale and Saxe, 2013). When we come to the realization that the beliefs of another person rather than reality determine that person’s behavior, we have a theory of mind (Frith and Frith, 2005).
Not all animals have a theory of mind. For instance, the current view posits that chimpanzees have a rudimentary theory of mind; however, other monkeys and animals do not (Frith and Frith, 2005). Thus, having a theory of mind is almost exclusively human. The advantage of humans developing theory of mind during evolution comes from manipulating others’ behaviors based on their beliefs. For example, we realize that another person’s knowledge is different from our own with theory of mind. If we see a tiger behind a tree but another person does not, we can warn a friend that it is not safe to proceed forward. If the other person is an enemy, we can tell them that it is safe to proceed. The latter example is called tactical deception or Machiavellianism (Frith and Frith, 2005). As a matter of fact, the vast majority of human interactions entail disseminating true from false knowledge for good or for ill will.
In order for one to formulate theory of mind of another, ‘mentalizing’ or ‘mind reading’ must take place, which involves acquiring knowledge of beliefs and desires of the other person. Our current understanding of the mechanism underlying this ability is rudimentary. One theory for how people formulate their theory of mind is ‘theory theory.’ ‘Theory theory’ posits that our ability to mentalize comes from the brain making representations of different behavioral propositions and weighing out the most likely options. Another theory, ‘simulation theory,’ posits that our abilities to mentalize come from empathizing with other people (putting ourselves in their shoes) (Frith and Frith, 2005).
The current view gives three brain regions with distinct roles in formulating a person’s theory of mind. Two of the regions lay toward the posterior of the brain (the posterior superior temporal sulcus and the temporo-parietal junction) and the other lays toward the front of the brain (the medial prefrontal cortex). The posterior superior temporal sulcus is thought to perceive actions of others using biomotion against scrambled biological motion. The temporo-parietal junction is thought to be involved in thinking about the desires and beliefs of others. Last, the medial prefrontal cortex is thought to be involved in thinking about people’s stable preferences and personalities (Koster-Hale and Saxe, 2013). One can ‘mentalize’ or ‘mind read’ another person based on the combination of data from these three brain regions.
Social development for participation in social activities depends upon theory of mind. By age five, most humans can distinguish reality from beliefs as measured through object placement tasks. Sadly, in some patients with disorders such as autism spectrum disorder, a strong theory of mind may never fully develop (Yang et al., 2015). Scientists have only begun to grasp the neural underpinnings of theory of mind, a psychological attribute that makes us uniquely human.
References
Frith C and Frith U (2005). “Theory of Mind.” Curr Biol 15(17): 644-645.
Koster-Hale J and Saxe R (2013). “Theory of Mind: A Neural Prediction Problem.” Neuron 79(5): 836-848.
Yang DY, Rosenblau G, Keifer C, and Pelphrey KA (2015). “An integrative neural model of social perception, action observation, and theory of mind.” Neurosci Biobehav Rev 51: 263-275.