Oxytocin
It has been shown that oxytocin differentially affects males and females. Females who are administered oxytocin are overall faster in responding to socially relevant stimuli than males who received oxytocin. Additionally, after the administration of oxytocin, females show increased amygdala activity in response to threatening scenes; however, males do not show increased amygdala activation. This phenomenon can be explained by looking at the role of gonadal hormones, specifically estrogen, which modulate the enhanced threat processing seen in females. Estrogen has been shown to stimulate the release of oxytocin from the hypothalamus and promote receptor binding in the amygdala.
Sexual motivation and hormones
The hormones oxytocin and vasopressin are implicated in regulating both male and female sexual motivation. Oxytocin is released at orgasm and is associated with both sexual pleasure and the formation of emotional bonds. Based on the pleasure model of sexual motivation, the increased sexual reproduction pleasure that occurs following oxytocin release may encourage motivation to engage in future sexual reproduction activities. Emotional closeness can be an especially strong predictor of sexual motivation in females and insufficient oxytocin release may subsequently diminish sexual reproduction arousal and motivation in females.