On Twitter yesterday, social psychologist Amy Cuddy asked psychologists what theme they believe to be generally true about human nature. Among the great responses was this by social cognitive neuroscientist Jay Van Bavel: “We are social animals.”
Indeed, in a new study, researchers have found that even when we are zoning out, we are preparing for our next social encounter. The work suggests the human brain’s default responses evolved to meet the needs of a social world.
In the study, led by Robert Spunt of the California Institute of Technology, participants performed different tests while researchers monitored their brain activity with fMRI. The idea was to see which regions of the brain are active in situations involving the “intentional stance” — the tendency for people to attribute specific intentions and beliefs to other people’s actions. They wanted to understand why we use the intentional stance so readily and easily to make sense of the world around us.
In the one of the tasks, researchers asked participants three types of yes or no questions: mind-focused; body-focused; or math. “The mind-focused questions evoked the intentional stance by asking participants to evaluate the appropriateness of a sentence describing the mental state of a person in a photograph,” Spunt says. For example, they would evaluate the sentence “He is gaining knowledge” with a photograph of a male looking down at a book while seated in a library (see photo at left). The body-focused questions — to look at the non-intentional stance — would have the sentence “He is looking at a book” for the same photograph. The math questions were there to suppress the brain activity in the default mode network (DMN).
The researchers wanted to see the brain activity during each type of question and in the breaks in between, and to measure the speed with which participants correctly answered the questions.
As published in the Journal of Cognitive Neuroscience, the researchers found that the brain activity activated when people took an intentional stance mirrored those for default responses, compared to the non-intentional stance. They also found that levels of brain activity in the dorsomedial prefrontal cortex (pFC) during the breaks was related to how easily participants were able to adopt the intentional stance when the break was over. And individuals who showed stronger dorsomedial pFC activity during the breaks in a follow-up test were not only more efficient when adopting the intentional stance, but also reported having greater social skills in their everyday lives.
Spunt talked with CNS about these results, the importance of understanding the intentional stance, and what it means for people with autism.
“Thinking about nothing” or “turning off your brain” is impossible. From birth to death, our brain’s gears are turning.
CNS: How do you define “intentional stance”?
Spunt: The “intentional stance” is a phrase coined by the philosopher Daniel Dennett to describe the tendency for humans to understand other people’s behavior as intentional and guided by beliefs and desires. That is, we seem to assume by default that people intend what they do because they want something and believe that doing what they do will help them get that something. When adopting this intentional stance, we think of people as more than just physical bodies subject to the laws of physics, but as non-physical minds with thoughts and feelings that may differ from my own.
CNS: Why is it important to study the intentional stance?
Spunt: It’s a pervasive aspect of human thought and discourse. Humans begin using it early in typical development and don’t stop using it for the rest of their lives. There is some evidence that the ability or tendency to “adopt the intentional stance” is abnormal in psychiatric illnesses such as autism. Hence, studying it should be a priority for the basic science of human behavior and for applied and translational science.
CNS: How did you become interested in studying this topic?
Spunt: I’ve always been fascinated by the compulsion that is mind/body dualism. I call it a compulsion because, at least to me, it is natural to think about others and myself as minds, and to think of minds as not-bodies. My particular fascination with this compulsion — that I do think most others share — regards the fact that, almost by definition, minds are unobservable. We never see a mind. We see facial expression and body movement. We see other people’s bodies interacting with physical objects, such as our own body. We see people’s lips move and hear sounds produced by the body’s vocal apparatus. And yet, if you were to show someone a photograph of a social situation and ask them “What do you see?”, I’d bet that nearly everyone would spend most of their time talking about stuff they can’t actually see. They’d draw inferences about the thoughts and feelings of the people in the situation. This is our tendency to adopt the intentional stance by default. And it’s incredibly important to our ability to thrive socially.
CNS: Were you surprised by any of the results?
Spunt: I confess I was surprised by the clarity of the priming effect we observed in the dorsomedial pFC. To be clear, this was an effect we predicted, and it is the effect we had most in mind when designing the study. My surprise was due to my skepticism that we would be able to see this effect in the data even if it were there, and my skepticism was due to the fact that we were using a somewhat novel approach to analyzing fMRI data, which is notoriously noisy.
CNS: What was the significance of the activity in the dorsomedial pFC as it relates to social skills?
Spunt: As we showed in this study, this region is part of the DMN and known to be activated by tasks that demand the intentional stance. In the first test, we found that within each participant, increases in activity in this region in response to the break preceding a mind-focused question was associated with faster response times when the participant gave the correct answer. We didn’t see this association for math questions or for body-focused questions, which asked participants to answer questions about the same set of social situations used in the mind-focused questions. So activity in this region during the breaks prepared participants to respond more efficiently to only those questions demanding the intentional stance.
The implication here is that default activity in the dorsomedial pFC component of the DMN helps us to respond in a socially adaptive manner when encountering other people. We were able to corroborate this finding by examining individual differences in default activity in this region during the follow-up test. Participants with the strongest default activity in this region were better at answering the mind-focused rather than body-focused questions. In addition, they reported having better social skills in their everyday lives. So, as we write in the paper, this “suggests that the early maturation of the DMN may be functionally critical in early development, providing children with a ‘jump start’ on acquiring the psychological skills necessary for understanding a complex and heterogeneous social world”.
CNS: What is the significance of your findings for the general population? As it relates to autism?
Spunt: This finding is yet another illustration that “thinking about nothing” or “turning off your brain” is impossible. From birth to death, our brain’s gears are turning. It goes further to say that even when we are completely zoned out and have nothing in particularly on our minds, our brains are hard at work preparing us to respond adaptively for our next encounter with a person. In fact, these are the times when we may be the most prepared for understanding others. The significance for autism is that it clarifies the known link between atypical DMN function and the apparent (although still controversial) “mind-blindness” in people diagnosed with autism spectrum disorders. People with autism seem to have trouble adopting the intentional stance, and they also seem to have atypical activity in the DMN during periods of rest.
CNS: What’s next for this work?
Spunt: There’s quite a lot to be done to flesh out our proposition that the DMN primes the intentional stance. The first is the dullest, but perhaps the most important: We need to examine the robustness of the effect. For example, will our effects replicate in a new sample? Will they be robust to variation in the methods used? Will the effects generalize to different subject populations? On the latter point, it’d be particularly fascinating to examine this in younger populations given the implications it has for the development of social skills. And, of course, the translational currency for this work is quite high. To this end, my current work is examining dorsomedial pFC function in relation to the intentional stance in high-functioning adults with autism.
-Lisa M.P. Munoz