A new study from a leading German university explores how stress can both strengthen in-group bonds and increase hostility toward outsiders. Published in a major scientific journal, the research provides a neurobiological lens on why group conflicts persist and how polarization takes hold in Thai communities and beyond.
Researchers in comparative psychology, with clinical neuroscience support from a major hospital, conducted a psychopharmacological experiment. Participants were given a cortisol analog to simulate stress, a drug to raise noradrenaline, both compounds, or a placebo. They formed groups and competed in economic games with real financial stakes to mirror cooperation and rivalry in real life.
The study centers on in-groups and out-groups—dynamics familiar to Thai communities with regional, social, and cultural loyalties. Participants could retain money, boost their group’s wealth at personal cost, or support their group while harming a rival. Losses to outsiders occurred only when helping the participant’s own group, illustrating intertwined motives of loyalty and competition.
Key findings show how the body’s stress response shapes social choices. Cortisol increased cooperation within one’s own group, even at personal cost. In contrast, higher noradrenaline amplified aggressive actions toward rival groups, even when personal gains were sacrificed. The lead researcher notes that stress does not universally drive aggression or cooperation; the dominant pattern depends on neurochemical pathways and whether the target is friend or foe.
These patterns help explain enduring “us versus them” attitudes seen in many societies. Group belonging can be advantageous in Thailand—within workplaces, sports clubs, and family networks—but the same mechanisms can fuel harmful rivalries during political or social tension. The findings offer a framework for interpreting regional, social, and political divides in Thai communities.
Beyond Thailand, the study resonates with moments when group identities influence national trajectories—such as urban–rural tensions or partisan divides. Understanding the biochemical drivers of these dynamics may help educators, health professionals, and community organizers design interventions that reduce unnecessary conflict while leveraging group strength.
Internationally, the research relates to current polarization and intergroup hostility, including online echo chambers and protest movements. High-stress environments—stemming from economic uncertainty, competition, or fear—can intensify attachment to familiar groups and suspicion of outsiders.
Experts place these results within a broader scientific context. Social psychology has long noted that stress can both divide and unite, but demonstrating specific neurochemicals that govern these effects sharpens the explanation. By identifying prevailing pathways under stress, researchers can help account for shifts in group behavior—from collective resilience during crises to mob-like behavior in demonstrations.
For Thailand, the findings suggest practical responses across education, health, and policy. Curricula could introduce the neurological basis of stereotyping and prejudice, fostering empathy across regional and social divides. Health professionals might consider how collective stress during disease outbreaks or economic hardship influences social cohesion. Policymakers could design community-level stress-reduction programs to promote trust and reduce polarization.
Practical takeaways for Thai readers include:
- View stress as an opportunity to build bridges rather than deepen divisions.
- Promote group activities that encourage cooperation while welcoming outsiders.
- Be mindful that social media and news can amplify stress and hostility; intentional breaks help maintain perspective.
- Create safe spaces for dialogue and stress management in workplaces, schools, and communities, especially during crises.
Ultimately, the study highlights the value of mindfulness, self-awareness, and open communication in countering the negative effects of stress on intergroup relations. In Thailand, where harmony is valued but tensions can surface, evidence-based approaches can support a more inclusive national identity.
Data from leading research institutions continues to shape our understanding of how stress influences social dynamics. For deeper insights into the neurobiology of stress and group behavior, readers can explore contemporary literature on group psychology and social cohesion.