ABSTRACT
This chapter examines how hypothalamic release and/or infusion of oxytocin modulate three critical aspects of human group psychologyin-group favoritism or in-group love. The oxytocin receptor gene (OXTR), located on chromosome 3p24-26, determines oxytocin receptivity and sensitivity in both neural tissue and other parts of the body such as the uterus and breast. Oxytocins targets include the amygdala, hippocampus, and regions of the spinal cord that regulate the parasympathetic branch of the autonomic nervous system. Oxytocin interacts with the hypothalamicpituitaryadrenal (HPA) axis to attenuate stress responses, and this has a pervasive influence throughout both the body and the brain. Pivotal in human group psychology is the tendency to quickly and often automatically conform to the majority opinion within ones group or social system. In humans, conformity can affect judgments ranging from low-level perceptual line-length estimates to more complex behaviors such as energy conservation.
