Event Abstract Back to Event Motor synchrony and the emergence of trust in social economics games Olivier Oullier1, 2*, Sylvie Thoron2, JeanâMarc Aimonetti3, Eric Guerci2, Pascal Huguet1 and Alan Kirman2 1 Aix-Marseille University, Cognitive Psychology Laboratory (UMR 6146), Universite de Provence & CNRS, France 2 Universite Paul Cezanne, GREQAM (UMR 6579), France 3 Aix-Marseille University, Human Neurobiology Laboratory (UMR 6149), Universite de Provence, France To date, experiments in economics are mainly restricted to settings in which individuals are not influenced by the physical presence of other people. Interactions remain at a somewhat abstract level with bodily signals being left out of the picture. However, in real life, how many times have we experienced the feeling that trusting someone will be difficult even before talking to them? Whether it was the way she moved or some other factor, bodyârelated cues seem to play key role in modulating economic decisions (e.g. mimicry and tipping). This is why we have decided to cross social coordination dynamics (SCD) with behavioral economics. SCD investigates the behavioral and neural mechanisms mediating the formation and dissolution of bonds between individuals. It offers new metrics to quantify human bonding (or lack thereof) at the sensorimotor level, and the selfâorganizing processes that underlie its persistence and change over space and time. SCD allows spontaneous motor synchronization while people interact and the degree to which their individual movements remain influenced a posteriori –some kind of motor social memoryâ to be computed in real time. Here, pairs of participants performed multiple rounds of the SCD paradigm and of a trust game in various fashions. Results indicate that the amount of money exchanged during the trust game is correlated to the stability of the sensorimotor patterns of spontaneous synchrony emerging between participants as well as the level of motor social memory. They constitute a first (experimental) step towards embodied economics.