Late Frontal Negativity Discriminates Outcomes and Intentions in Trust-Repayment Behavior.

Area of Science:

• Neuroscience
• Behavioral Economics
• Social Psychology

Background:

• Altruism involves outcome preferences, while reciprocity requires inferring intentions.
• Direct comparison of neural and behavioral responses to outcome- vs. intention-based interactions is lacking.
• Understanding these distinct social decision-making processes is crucial.

Purpose of the Study:

• To directly compare human behavior and neurophysiological activity in outcome-based (altruism) versus intention-based (reciprocity) economic interactions.
• To investigate the influence of varying endowment sizes on these responses within the same session.
• To identify neural correlates differentiating altruistic and reciprocal behaviors.

Main Methods:

• Utilized a mixed design of the Dictator and Investment games.
• Employed electroencephalography (EEG) to record brain activity.
• Tested subjects with different endowment sizes in altruistic and reciprocal contexts.

Main Results:

• Subject behavior exhibited positive or negative reciprocity contingent on the level of trust received.
• Late frontal negativity in EEG signals differed between conditions, predicting responses to trust in intention-based trials.
• Brain regions associated with mentalizing and cognitive control were identified as neural sources.

Conclusions:

• Behavioral responses to trust repayment are disentangled, differentiating between altruistic and reciprocal actions.
• Neural activity underlying the integration of outcomes and perceived intentions in economic decisions is illuminated.
• This research provides insights into the neural basis of social economic interactions.