Scientists at a major university in Japan found that when people interact socially, their brain activity starts to align across individuals. The discovery suggests that during real conversations and cooperative tasks, the neural patterns in one person begin to mirror those in their partner, hinting at a shared processing network that supports social connection and joint problem solving. The study was reported in a neuroscience journal and adds to the growing view that social behavior emerges from coordinated brain activity across people rather than isolated brain processes.
To truly grasp how the brain generates social behavior, researchers must observe it in action during live encounters. That means tracking brain signals from multiple participants in real time as they communicate, plan, and work toward a common goal. In this work, researchers conducted a series of interactions involving 39 pairs of participants. Each pair faced a common objective: design and arrange a virtual room in a computer game. Free dialogue and collaboration were encouraged so that both participants could contribute ideas and reach a mutual decision. For comparison, the same task was completed individually by participants who worked alone.
The data analysis revealed a pattern: during joint activity, synchronized activity emerged in the temporal regions of the brain, including the superior and middle temporal areas, as well as specific regions of the prefrontal cortex on the right side. Synchrony was particularly pronounced when participants directed their attention toward one another, observing each other’s gaze and responses as the task progressed. These findings point to a neural mechanism in which two brains, through social interaction, momentarily function as a single system to support creative problem solving and shared decision making.
The researchers described the phenomenon by noting that when collaborators worked together, neuron populations in one brain fired in step with similar populations in the partner brain. This alignment suggests a temporary coupling of brains that facilitates coordinated thought and collaborative insight, offering a compelling view of how human cooperation emerges from synchronized neural dynamics.