Propensity to Punish in High Psychopathy may Promote Cooperation: Human and Computer Prisoner Dilemma Experiments

Area of Science:

• Psychology
• Behavioral Economics
• Computational Social Science

Background:

• Psychopathy is a personality construct characterized by antisocial behavior, manipulativeness, and callousness.
• The adaptive hypothesis suggests that psychopathic traits may confer evolutionary advantages in certain social contexts.
• The Prisoner's Dilemma (PD) is a game theory model used to study cooperation and defection.

Purpose of the Study:

• To test the adaptive hypothesis of psychopathy using human and computer simulations of the Prisoner's Dilemma.
• To investigate how high and low psychopathy (PP) influence strategic decision-making and outcomes in PD matches.
• To explore the proliferation dynamics of psychopathic traits in social interactions.

Main Methods:

• Recruited 448 male undergraduates, assessing psychopathy using the Levenson Self-Report Psychopathy Scale (LSRP).
• Selected 31 high PP and 29 low PP students for 40-round PD matches with real monetary stakes.
• Conducted computer simulations incorporating empirical defection probabilities from human players against Tit-for-Tat (TFT) and other strategies.

Main Results:

• High PP players earned more against Low PP players but less against other High PP players in human matches.
• In computer simulations, TFT drove both High and Low PP strategies to extinction.
• However, the High PP strategy drove both Low PP and a less cooperative TFT variant to extinction.

Conclusions:

• Psychopathic traits can proliferate through both low-level selfish behavior and high-level deterrence of defection via punishment.
• The study suggests that in silico environments, randomness in social encounters may favor psychopathic strategies over altruistic ones like TFT.
• Findings highlight the complex interplay between personality traits, strategic interactions, and evolutionary dynamics in social decision-making.