The cultural transmission of cooperative norms

Cooperative behavior depends on cultural environment, so what happens when people move from to a new culture governed by a new norm? The dynamics of culture-induced cooperation has not been well understood. We expose lab participants to a sequence of different subject pools while playing a constrained Trust Game. We find prior exposure to different subject pools does in fact influence cooperative behavior; first impressions matter-the primacy effect plays a stronger role than the recency effect; and selfish first impressions matter more than cooperative first impressions-observing selfish behavior by others had a longer-lasting and greater influence on behaviors than observing cooperative behavior by others. Moreover, three consecutive exposures to cooperative environments were needed to neutralize one exposure to a selfish environment.