Thinking about other people’s thoughts
The Saxe Lab studies the mechanisms of social cognition and their development in the human brain
Courtesy of Kris Brewer
Consider the following thought experiment: Person A and Person B, on a tour of a chemical factory, stop to take a coffee break. Person A finds a pot containing white powder — a powder which is actually sugar, but is labeled “deadly poison.” Person A put some of this powder into Person B’s coffee; Person B drinks it and remains perfectly healthy.
How morally permissible was it for Person A to put the powder into Person B’s coffee? Should they be blamed for this failed attempt to harm?
Questions like these and more drive professor Rebecca Saxe’s research in the McGovern Institute for Brain Research. Saxe, also the associate head of the Brain and Cognitive Sciences Department, posed this “deadly poison” hypothetical to the audience of her 2009 TED talk, “How we read each other’s minds.” Her lab focuses on understanding social cognition and the development of the human brain. As Saxe explained in her TED talk, the job of a cognitive neuroscience researcher is “to understand how you can put together simple units — simple messages over space and time — in a network and get this amazing human capacity to think about minds.”
One brain region in particular is responsible for this task of “thinking about other people’s thoughts,” as Heather Kosakowski, a graduate student in Saxe’s lab, explained. The right temporo-parietal junction (RTPJ), located above and behind the right ear, displays increased activity when individuals think about what others are thinking, but not when they perform other mental tasks. In 2005, Saxe published a paper in Neuropsychologia highlighting the role of the RTPJ in such cognitions. “It’s become known as part of the theory-of-mind network,” said Kosakowski, and a central question that remains is “how does that [network] develop or emerge?”
This question served as the inspiration for much of the other work produced by the Saxe Lab and, in particular, for Kosakowski’s efforts. “I think trying to understand what is going on at the beginning of human life in the brain — what can babies understand? What do they know? What don’t they know? — are some of the most fascinating questions there are,” she said.
In order to uncover the neural mechanisms underpinning infant cognition, Kosakowski is expanding on a project originally conducted by Saxe and her former graduate student Ben Deen. Using functional magnetic resonance imaging (fMRI), Saxe and Deen measured babies’ responses to different visual categories, such as faces and scenes. Although Saxe and Deen discovered similarities between the locations and levels of neural responses in infants and adults, their study only included data from nine babies.
Now, Kosakowski is working to replicate Saxe and Deen’s study, expanding it to include data from up to 26 infants and in response to bodies and objects as stimuli. Her ultimate aim is “to figure out: what is the starting state of the infant brain? Can we tease apart some of the developmental theories about the origin of knowledge and competing theories in cognitive development?”.
The day-to-day logistics of such infant studies, however, are anything but straightforward. “Something people find surprising about baby research is how much work actually goes into getting a baby through the door,” Kosakowski explained. “There’s a lot of work that goes into recruiting and scheduling visits with babies.” The extensive data analysis that follows is compounded by other complications — babies’ movement in the fMRI scanner or falling asleep, for example. “Getting a baby in is a challenge, getting data from a baby is a challenge, and analyzing data is a challenge,” Kosakowski said.
Still, the Saxe Lab remains a trailblazer in the field of infant brain research because — unlike most fMRI studies, which analyze data from sleeping babies — Saxe has “really pioneered research with awake babies,” Kosakowski said. Her lab and others are starting to “ask interesting questions about what’s going on across the infant brain when infants are awake.”
Yet the Saxe Lab is notable for more than just its research. The culture and values of any lab are important factors that shape the direction of its work; according to Kosakowski. “[Saxe] is really unique as a scientist, as a mentor, and as a person,” she explained, “in that she works really hard to build a diverse lab group.” Many academic scientists follow a “very traditional trajectory” through their careers, ultimately resulting in an increasingly homogenous culture with “brilliant people — but brilliant people who all really think very similarly,” said Kosakowski.
“[Saxe] recognizes that quality science requires a diverse type of thinking and does what she can to make that happen,” finding individuals for her lab who do not adhere to this typical academic trajectory, Kosakowski added. “She tries to push back at norms and question their validity in attempts to increase inclusiveness and also to increase the quality of her science.” Particularly in a field which examines the ways people think and the developmental reasons for that thinking, the decision to choose researchers with diverse sources and lines of thought is critical.
Down the road, the Saxe Lab plans to continue asking and seeking answers to the questions that have always motivated their research: how does the human brain construct thoughts? What is the starting state of the brain? How does experience shape brain responses? According to Kosakowski, studies on the neural basis of navigation, social reward learning, and language learning in infants — as well as Kosakowski’s fMRI study on infants’ visual preferences — are ongoing in the lab. Ultimately, “there’s so much room there to explore more,” she said.
As Saxe put it in her TED talk, “The whole project of understanding how brains do the uniquely human things — learn language and abstract concepts, and thinking about other people's thoughts — that's brand new. And we don't know yet what the implications will be of understanding it.”
Update 11/3/19: The photo accompanying this article was originally attributed to the Saxe Lab, but has been updated to be correctly attributed to the photographer, Kris Brewer.