Igor Kagan, Ph.D.

• Group Leader
• German Primate Center

Behavioral and neuronal dynamics of transparent social decisions

Many real-world social interactions unfold in continuous time and space under conditions of mutual action visibility. I will present our work on the dynamic strategic coordination that underlies such face-to-face, embodied interactions. First, I will summarize the behavior of macaque and human dyads in a transparent version of the Bach-or-Stravinsky decision game, which rewards coordinated choices but imposes an inherent conflict [1]. While humans primarily adopted dynamic, prosocial turn-taking strategies to equalize payoffs, macaques converged on simpler, static coordination. After training with a human confederate, macaques learned to coordinate dynamically, but when paired together, often reverted to competitive turn-taking. I will then demonstrate how single neurons and neuronal populations in the macaque premotor cortex encode anticipated and observed actions of predictable and unpredictable partners, integrating this information with own goals and choices — a process critical for dynamic coordination.

Second, I will illustrate the diversity of stable cooperative, competitive, and intermediate strategies that spontaneously emerge in human dyads interacting in a continuous foraging game [2]. Using a model that integrates sensorimotor computations and social signaling with choice history, I will show how embodied factors — effort, speed, skill, and partner’s ongoing movements — shape distinct strategies and outcomes. I will also quantify the cost of prosocial cooperation in dyads where group success outweighs the individual benefit of exploiting skill advantages. I will conclude by summarizing how action visibility supports the emergence and maintenance of dynamic cooperation and competition, against the backdrop of social attitudes in humans and macaques, and outlining future research directions.

Faculty Host: Dr. Veit Stuphorn