Relationship Between Neuroticism Personality Trait and Serotonin Transporter Binding

Background Personality trait is thought to be one of the important factors for vulnerability to depression. The relation between serotonin transporter (5-HTT) polymorphism and anxiety-related personality has been investigated in genetic research. In this study, we investigated the relation between in vivo regional 5-HTT binding in the brain and personality inventory measures in normal male volunteers. Methods Thirty-one healthy male volunteers underwent positron emission tomography scans with 11C-labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl) benzonitrile ([11C]DASB) to measure 5-HTT and completed revised NEO Personality Inventory. Correlation of [11C]DASB binding potentials (BP) with personality inventory measures was calculated using region-of-interest analysis and statistical parametric mapping based on the BP images. Results Neuroticism was positively correlated with 5-HTT binding in the thalamus (p = .004). No significant correlation was observed in any other brain region. Within the neuroticism dimension, the facet of depression was positively correlated with 5-HTT binding in the thalamus (p = .001). Conclusions Subjects with higher thalamic 5-HTT binding are more likely to express higher levels of neuroticism and depressive feeling. Serotonin transporter binding in the thalamus might be a marker of vulnerability to depression.