Mechanisms of Social Learning in Social Contagion and Cultural Evolution

Social learning – learning from the behaviors of others – is key for our success as a species. Ideas and behaviors are transmitted between individuals and across generations via social learning, which gives rise to the evolution of human cultures. Social learning might also fuel modern threats, such as the growing social contagion of misinformation in social networks. Despite the crucial role of social learning across a myriad of human behaviors, surprisingly little is known about the (i) psychological, neural and computational mechanisms of social learning, and (ii) how these mechanisms create societal-level phenomena. The SOLAR project takes on the challenge of developing a new theoretical framework that addresses these issues. The framework will be formalized in novel computational models. The same coherent set of models will be tested on (i) the level of the brain using brain-imaging, (ii) the level of individual behavior, and (iii) the level of the population, using multi-agent simulation and analysis of real-world interaction in social networks. SOLAR involves three programs that address three fundamental, but as-of-yet unanswered questions about human social learning: (1) What are the mechanisms that produce social learning? (2) Does social learning drive social contagion? (3) How does social learning promote cultural evolution? In contrast to previous accounts, I predict that these seemingly disparate questions can be unified and understood by a coherent set of simpler social reinforcement learning mechanisms. I will test this hypothesis with a unique multi-method approach that bridges the “nano-level” of the brain, via the micro-level of human behavior, to the macro-level of the social group. SOLAR will shed new light on both fundamental scientific questions about the nature of human social learning, and on pressing social issues, such as how to explain and reduce collective risks due to social contagion (e.g., spreading of misinformation).