Transformative psychology #12: Neuroscience of consensus, or what part of the brain produces groupthink?

In 2011, a Stanford psychologist discovered a function of the:

"ventromedial prefrontal cortex, a part of the brain's reward centre that lights up when we encounter things we want, like a chocolate bar. Zaki's team found that it also activates when people are told what others think. And the more this part of the brain responds to information about group opinion, the more someone will adjust their opinion towards the consensus" (Rutkin, 2025, p. 32).

Some wrote about this decades ago when analyzing the process of the "best and brightest" American officials in John F. Kennedy's cabinet, who all came to agree to invade Cuba's Bay of Pigs in an attempt to overthrow Fidel Castro, an invasion that was so poorly thought out that it ended in abject humiliation for the US. 

Achieving real consensus is more than a powerful and persuasive person convincing a group to get along by going along. Part of the successful application of psychology toward genuine consensus is credible humility by the figure usually regarded as the decider--the owner of a company, the founder of a group, the most credentialed member of a group, the person who is looked to for wise decisions by others, or even simply a dominant personality. 

Checking ego, checking any ability to pull rank, checking any potential for retribution, checking one's high position in a hierarchy--all this is requisite to authentic consensus process, a process that, when done well, produces wise decisions and high commitment to results by those who were participants in that process (Dressler, 2006).

References

Dressler, Larry (2006). Consensus through conversation: How to achieve high-commitment decisions. San Francisco, CA: Berrett-Koehler.

Rutkin, A. (2015). We Are Wired to Conform. New Scientist, 227(3034), 32.