Saturday, June 12, 2010

Oxytocin -- the Meanie Hormone?

This week's Mark Steyn column about people with and without loyalty to their homelands is an interesting counterpoint to some new research about group bonding. Pointy-headed experts have published the alarming news that that oxytocin, the happy love hormone, has a “dark side” in which its “niceness breaks down.” It seems that warm bonds between human beings may lead to their joint aggression against outsiders, particularly in defensive mode. (If only we could dissolve all those uncontrollable bonds among individuals and transfer their unconditional loyalty to the World Government! Then people would stand by while their comrades were under attack.)

The researchers used the “Prisoner's Dilemma” game to test the effects of oxytocin. In this game, the reward that each player can expect will range from highest to lowest in the following three scenarios:

  1. the first player betrays the other while the other is loyal;

  2. both cooperate; and

  3. each betrays the other.

The optimal solution for a single player is betrayal, while the optimal solution for the two players considered together is cooperation. When the game is played only once, betrayal is the winning strategy from the point of view of that player, even though it is not optimum if you consider both players. The researchers used this aspect to judge the effects of oxytocin on the decision whether to betray.

What the researchers didn’t look at, apparently, is another and more interesting aspect of the Prisoner’s Dilemma. If the game is played repeatedly, the long-term winning strategy is not simple betrayal but “tit for tat,” in which a player begins by cooperating, then responds to the other player’s betrayal or cooperation in one turn with the same choice in the next. A slight variation, which can prevent both players from getting trapped in a cycle of defections, is “tit for tat with forgiveness,” in which the first player very occasionally (and unpredictably) responds to a betrayal in one move with cooperation in the next. The “tit for tat” game strategy tends to result, over time, in the players’ learning to trust each other and to behave themselves.

In other words, they form a bond. Probably reeking of oxytocin – and they’ll be ready to join forces to kick the butts of the next group of strangers who show up threatening to use the short-sighted betrayal strategy.


  1. I remeber a post by Bill Whittle regarding the "tit for tat" strategy in regards to international relations. It may still be available at Eject,Eject,Eject and is certainly an interesting read, as are most of his posts.


  2. Years ago, Arthur Koestler argued that wars are caused more by misdirected altruism than by selfishness.