Abstract: The sexual dimorphism in structure and function of the brain causes gender differences in fear emotion processing. Fear emotion processing is affected by estrogen and progesterone in women. Recently, the research combination of the human brain mapping technology, genetic and animal molecular biology methods found that the neural mechanism of fear emotion processing under the influence of ovarian hormone in women. Particularly, increasing level of estrogen leads to intense amygdala activity then enhanced the fear face recognition accuracy in women, while the effect of the progesterone level is opposite. They are related to the demands for social interaction and self-protective mechanism in the different phases of the women’s menstrual cycle.

Key words: sexual dimorphism, fear processing, neural mechanism, ovarian hormone