Researchers at Northwestern Medicine have conducted a study to explore the evolution of human social cognition. The study aimed to understand how humans developed the ability to think about what others are thinking, a process believed to be facilitated by recently evolved brain regions.
Senior author Rodrigo Braga explained, “We spend a lot of time wondering, ‘What is that person feeling, thinking? Did I say something to upset them?’ The parts of the brain that allow us to do this are in regions of the human brain that have expanded recently in our evolution, and that implies that it’s a recently developed process.”
The research revealed that newer areas of the brain involved in social interactions are linked with an older part known as the amygdala. This connection provides insight into how these regions communicate constantly. The amygdala, often referred to as the "lizard brain," is traditionally associated with threat detection and fear processing but also plays roles in social behaviors like parenting and aggression.
Braga noted, “Previous studies have found co-activation of the amygdala and social cognitive network, but our study is novel because it shows the communication is always happening.”
The study was published on November 22 in Science Advances. It used functional magnetic resonance imaging (fMRI) data from six participants' brains provided by Kendrick Kay from the University of Minnesota. These high-resolution scans allowed researchers to identify details within the social cognitive network previously unseen.
Donnisa Edmonds highlighted this advancement: “One of the most exciting things is we were able to identify network regions we weren’t able to see before.”
This discovery could inform treatments for anxiety and depression, conditions involving amygdala hyperactivity. Edmonds mentioned potential non-invasive treatments using transcranial magnetic stimulation (TMS) based on these findings: “Through this knowledge that the amygdala is connected to other brain regions — potentially some that are closer to the skull, which is an easier region to target — that means people who do TMS could target the amygdala instead by targeting these other regions.”
The research team included Christina Zelano, Joseph J. Salvo, Nathan Anderson, Maya Lakshman, and Qiaohan Yang from Northwestern University Feinberg School of Medicine. The study received support from various grants including those from National Institute of Mental Health and National Science Foundation.