The role of the amygdala in interpersonal trust

Abstract

The trust is fundamental to a good interpersonal relationship, being one of the most important dimensions of the prosocial behaviors. However, knowledge about the biological basis of trust is still incipient. Researches suggests that the oxytocinergic system plays an important role in establishing interpersonal trust and that the amygdala - brain structure with high density of oxytocin (OT) receptors and highly recruited in the processing of socio-emotional information - is directly implicated in the manifestation of trusting behaviors. In this domain, studies have shown associations between OT receptor gene polymorphism (rs53576) and differentiated interpersonal trust profiles. Thus, this research aims to analyze the relationships between OT receptor gene polymorphism (rs53576), neuroimaging of the amygdala and the behavioral manifestation of trust. The data collection is being carried out in two parts: in the first part, blood samples are collected for genotyping of the rs53576 polymorphism and the completion of a questionnaire to evaluate trust expression; in the second part, Functional Magnetic Resonance Imaging (fMRI) exams are being performed to obtain functional and structural data on the amygdala while the collaborators perform economic game and human face reliability tasks that imply reliable judgments. The participants (N = 30) will be men, over 18 years, right-handed and clinically healthy. The collected data will allow to analyze the relations between the rs53576 polymorphism and neuroimaging in the expression of interpersonal trust behaviors. (AU)