Differential relationships between personality and brain function in monetary and goal-oriented subjective motivation: multichannel near-infrared spectroscopy of healthy subjects.

AIM

To examine relationships between personality traits and cerebral cortex reactivity under different motivating conditions.

METHODS

Relationships between personality traits assessed using the NEO Personality Inventory-Revised (NEO-PI-R) and cerebral cortex reactivity during a verbal fluency task monitored using multichannel near-infrared spectroscopy (NIRS) were examined under three different motivational conditions: control, monetary reward, and goal-oriented, in healthy young male volunteers.

RESULTS

Significant correlations between cerebral cortex reactivity and personality traits were found in the frontopolar region: a positive correlation with agreeableness and a negative correlation with the neuroticism and conscientiousness scores of the NEO-PI-R under the three motivational conditions. Higher scores for agreeableness were more strongly associated with a greater increase in total hemoglobin concentration ([total-Hb]) under the goal-oriented and control conditions than under the monetary reward condition. In addition, higher scores for neuroticism were more strongly associated with a greater increase in deoxygenated hemoglobin concentration ([deoxy-Hb]) under the monetary reward condition than the goal-oriented condition, and higher scores for conscientiousness were more strongly associated with a greater increase in [deoxy-Hb] under control conditions than under the goal-oriented condition.

CONCLUSION

Using multichannel NIRS, certain personality traits of the big-five model are related to frontopolar reactivity. These relationships vary depending on the motivational condition when brain functions are monitored: agreeableness, neuroticism, and conscientiousness are all related to frontopolar reactivity depending on the motivational condition.