The brain structural disposition to social interaction.

Area of Science:

• Neuroscience
• Psychology
• Behavioral Science

Background:

• Social reward dependence (RD) is a personality trait reflecting a positive disposition towards social relationships and attachment.
• It is theorized that RD is linked to the brain's capacity for processing primary rewards.

Purpose of the Study:

• To investigate the neuro-anatomical basis of social reward dependence in men.
• To explore the relationship between brain structure and individual differences in social RD.

Main Methods:

• Utilized magnetic resonance imaging (MRI) to measure brain structure in 41 male subjects.
• Assessed social RD using Cloninger's temperament and character inventory, a self-reported questionnaire.
• Sampled subjects from a general population birth cohort.

Main Results:

• Found a significant association between higher social RD and increased gray matter density.
• Identified specific brain regions with increased gray matter density: orbitofrontal cortex, basal ganglia, and temporal lobes.
• These regions are known to be involved in processing primary rewards.

Conclusions:

• Provided evidence for a brain structural predisposition towards social interaction.
• Suggested that sensitivity to social reward shares a common neural basis with systems for processing primary reward information.
• Highlighted the link between personality dimensions and specific brain structures.