The effects of intragroup communication on intergroup cooperation in the repeated intergroup prisoner's dilemma (IPD) game

The intergroup prisoner's dilemma (IPD) game was played repeatedly in an at tempt to distinguish the dynamic process associated with reciprocation at t he intergroup level from that resulting from adaptation at the individual l evel. Results show that when players were not allowed to communicate with o ne another, they gradually learned that it does not pay to participate, but when within-group communication was allowed, the overall effect was to inc rease individual participation. However, this effect varied greatly in late r stages of the game. In some cases, intragroup communication eliminated in dividual participation and rewarded the members of both teams with the mutu ally cooperative outcome, but in other cases, it intensified the intergroup conflict to its maximal level of full participation. The implications of t hese findings for conflict resolution are discussed.