Brain activity in fairness consideration during asset distribution: does the initial ownership play a role?

Area of Science:

• Neuroscience
• Cognitive Psychology
• Behavioral Economics

Background:

• Initial ownership influences fairness considerations and behavior.
• The neural correlates of fairness evaluation under initial ownership are not fully understood.

Purpose of the Study:

• To investigate the effect of initial ownership on brain activity (event-related potentials) during fairness evaluation in the ultimatum game.
• To determine how initial ownership modulates the neural processing of unequal versus equal asset distributions.

Main Methods:

• Participants acted as recipients in an ultimatum game, receiving disadvantageous unequal, equal, or advantageous unequal offers.
• Initial ownership of the monetary reward was randomly assigned to either the allocator or the recipient.
• Event-related potentials (ERPs) were recorded during the decision-making process.

Main Results:

• Behaviorally, participants rejected disadvantageous offers more when they initially owned the property.
• Early ERPs (MFN) showed differences between unequal and equal offers, unaffected by initial ownership.
• Late ERPs (P300) were modulated by offer type and initial ownership, indicating top-down processing.

Conclusions:

• The MFN may represent a general equity rule violation detection mechanism.
• The P300 reflects attentional resource allocation influenced by ownership and self-interest in fairness evaluation.
• Initial ownership significantly impacts neural responses to fairness, particularly in later cognitive processing stages.