Interpersonal relationship modulates the behavioral and neural responses during moral decision-making

Area of Science:

• Neuroscience
• Social Psychology
• Moral Psychology

Background:

• Interpersonal relationships (IR) are crucial in human interaction.
• The impact of IR on neural and behavioral aspects of moral decision-making remains underexplored.

Purpose of the Study:

• To investigate how different levels of intimacy in interpersonal relationships (friends, acquaintances, strangers) affect emotional and cognitive processes during moral decision-making.
• To examine the temporal dynamics of these effects.

Main Methods:

• Utilized a dilemma scenario-priming paradigm.
• Compared neural and behavioral responses across different intimate relationship conditions (friend, acquaintance, stranger).
• Analyzed event-related potentials (ERPs) including N1, P260, and Late Positive Potential (LPP).

Main Results:

• Participants exhibited less altruistic decisions and longer decision times for strangers compared to friends and acquaintances.
• Increased negative emotional responses and dilemma conflicts (indicated by P260 amplitude) were observed for strangers.
• Later cognitive appraisal processes (indicated by LPP amplitude) also showed differences for strangers, but not between friends and acquaintances.

Conclusions:

• Interpersonal relationships significantly modulate emotional and cognitive processing during moral decision-making.
• Closer relationships lead to weaker dilemma conflicts and emotional responses.
• Relationship closeness enhances the efficiency of resolving moral dilemmas.