Mental attributes and temporal brain dynamics during bargaining: EEG source localization and neuroinformatic mapping.

Area of Science:

• Neuroeconomics
• Cognitive Neuroscience
• Decision Sciences

Background:

• Previous fMRI studies linked unfair offers in ultimatum games to emotional brain regions, but lacked temporal precision (∼2 s).
• Understanding the fine-grained temporal dynamics of emotional processing and mental attributes in decision-making remains a challenge.

Purpose of the Study:

• To investigate the temporal dynamics of neural activations during the ultimatum game using high-density electroencephalography (EEG).
• To identify specific brain regions and mental attributes associated with offer rejection with millisecond-level resolution.

Main Methods:

• EEG data from responders during an ultimatum game were analyzed using independent component analysis and dipole source localization.
• Multiple regression analysis was applied to time-resolved epochs (250 ms) to correlate neural activity with behavioral rejection responses.
• Talairach coordinates of localized sources were mapped to brain regions and mental attributes using the Brede database.

Main Results:

• High temporal resolution EEG revealed neural activations missed by time-averaged fMRI analyses.
• Significant temporal epochs and fluctuations in brain regions (e.g., anterior cingulate cortex, insular cortex) correlated with mental attributes like anger and unfairness.
• A sequential activation pattern of the anterior cingulate cortex followed by the insular cortex was observed preceding offer rejection.

Conclusions:

• EEG with source localization offers superior temporal resolution for studying neuroeconomic decision-making.
• The findings elucidate the rapid, sequential neural processes underlying emotional responses to unfairness.
• The developed regression models accurately predict behavioral responses, highlighting the potential of EEG in neuroeconomics.