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We’ve all been there—assuming things about people before we even get to know them. Maybe it’s thinking that someone younger needs more guidance or that someone quiet won’t have much to say. These stereotypes are mental shortcuts our brains take, but they don’t always match reality. So, what happens when our assumptions clash with the facts? How does the brain adapt?
New research from Radboud University and Dartmouth College sheds light on this fascinating question. The researchers designed a unique nonverbal communication game to explore how stereotypes and real-time feedback shape our social interactions.

How stereotypes and real-time evidence influence behavior
In the study, participants played a digital board game where they alternated between working with a “child” and an “adult.” To make this convincing, a photo of either a child or an adult appeared before and during each task. In reality, both roles were played by the same trained actor. Participants were asked to help their “partner” find a hidden object on a digital game board by moving a bird avatar to signal its location. Interestingly, they spent more time guiding the “child,” reflecting a common belief that children need more help. For example, participants paused longer on the square containing the hidden object when they thought they were guiding a child. However, the “child” and “adult” completed the tasks with identical accuracy and speed, as the same actor controlled their performance
Watch this short video to see how the experiment worked.
The brain’s role: The anterior cingulate gyrus in action
A key finding of the study was the role of the anterior cingulate gyrus (ACC), a brain region crucial for adapting behavior during social interactions. At the start of the task, participants relied on stereotypes, and the ACC showed heightened activity as it worked to reconcile these assumptions with new evidence from their partner’s performance. As participants observed that both the “child” and “adult” partners performed equally well, the ACC activity decreased, reflecting a shift toward evidence-based communication.
This pattern highlights the ACC’s function in managing the conflict between preconceived notions and actual feedback during interactions. Beyond stereotype adjustment, the ACC is involved in broader social processes, such as empathy and decision-making, helping us refine our behavior based on new information.
Early life experiences shape how we communicate
The study also uncovered a fascinating connection between early social experiences and stereotype adjustment. Participants who spent more time in daycare as toddlers—interacting with diverse groups of people—were better at basing their communication on evidence rather than assumptions. This suggests that growing up in socially diverse environments helps develop flexibility in thinking and communication.
These findings highlight the lasting impact of early interactions. Growing up in socially diverse settings teaches us to rely on firsthand experience rather than defaulting to ingrained assumptions.
Why Does This Matter?
Assuming a younger person needs extra guidance might seem harmless, but such stereotypes can be harmful when they reinforce prejudice or bias—making decisions based on assumptions rather than facts. Like having unfair judgments about someone’s abilities just because of their age or background.
Understanding how the brain integrates stereotypes with evidence, we can foster more equitable communication. Training ourselves to rely on observed feedback over assumptions may help us overcome ingrained biases and improve social interactions. This research reminds us that while our brains often take shortcuts, they are also remarkably adaptable. With the right experiences and effort, we can challenge stereotypes, adjust our behavior, and build stronger, fairer connections with others.
Credits
Author: Amir Homayun Hallajian
Buddy: Helena Olraun
Editor: Elena Markantonakis
Translation: Dirk-Jan Melssen
Photo by Priscilla Du Preez on Unsplash