Trust in Physicians and Regional Brain Volumes: A Population-Based Study.

OBJECTIVE: Trust, a fundamental part of human interpersonal relationships, is known to be associated with specific brain regions and demographic characteristics. Level of trust in medical professionals can alter population health outcomes and influence the nature of the doctor-patient relationship. This study utilized structural magnetic resonance imaging (MRI) and trust data from the Dallas Heart Study (DHS), a large community-based study, to determine brain regions associated with degree of trust in physicians and the medical profession. The first phase of the DHS was conducted from 2000 to 2002 and the second phase from 2007 to 2009. METHODS: The MRI data were analyzed as part of the DHS using automated FreeSurfer software. Forward stepwise binary logistic regression was performed to investigate the association between measures of trust and bilateral brain region volumes and thickness followed by confirmatory multiple regressions of significant brain regions. A total of 1,596 participants were included in the final analysis. RESULTS: Left caudal anterior cingulate cortex (ACC) thickness was inversely correlated with trust of physicians (P < .01). There were no significant associations between trust in physicians and age, race or ethnicity, or education. CONCLUSIONS: The ACC is an integral part of the salience network, the brain network responsible for communication and social behavior. Trust in physicians did not appear to be influenced by demographic characteristics. The findings suggest there are neuroanatomical correlates of trust in physicians.

Relationship between trust in neighbors and regional brain volumes in a population-based study.

Trust is a fundamental part of human interpersonal relationships, and among other complex factors it is shown to be linked with demographic characteristics and specific regions of the brain. The authors utilized a large, community-based database gathered from the Dallas Heart Study to determine specific brain regions associated with an individual's trust in neighbors. A trust questionnaire was taken and regional brain volumes were determined from structural magnetic resonance imaging. Two analyses using logistic regressions in a training set and validation set were performed to investigate the association between measures of trust and bilateral brain region volumes and thickness. A total of 1527 participants were included in the final analysis. Right caudal anterior cingulate cortex thickness and left caudate volume were inversely correlated with neighbor trust, while left amygdala volume was positively correlated with neighbor trust. Greater age and higher level of education were positively correlated with neighbor trust. African Americans showed less neighbor trust than Caucasians and Hispanics. Anterior cingulate cortex, caudate, and amygdala are all integral parts of the salience network; thus, results of this study suggest that the salience network, the brain network responsible for functions such as communication and social behavior, may play a role in the formation of interpersonal trust.