Nce more likely to trust in the TG. Similarly, subjects with high plasma OT indicating increased social sensitivity and motivation would also show enhanced trust/trustworthiness driven by the warm glow of positive social interactions incurred in participating in the TG. There is a large body of literature in evolutionary biology on gender differences regarding reproduction and investment cost towards offspring [51]. As females usually incur higher costs for reproduction including giving birth and raising offspring, it is suggeseted that females will increase their fitness (number of viable offspring) by investing heavily in fewer children but insuring their the survival. On the other hand, males would increase their fitness by accessing to the maximum number of females they can mate with since the male investment in child bearing and rearing is lessPlasma Oxytocin and Trustthan the female. The behavioral consequences of gender difference in reproduction are unclear. It is, however, possible that these different investment strategies could lead to different psychological mechanisms towards trust and trustworthiness but also different biological mechanisms underpinning these two constructs for each of the sexes. In our findings, although the relationship between plasma OT and trust related behavior is significant in the pooled sample, separate analysis by gender revealed that the effects are more specific to the male side. This is in agreement with a large number of animal studies suggesting that OT differentially affects females and males, likely reflecting the interactions between OT and gonadal hormones [52,53]. 
Indeed, the effects of neuropeptides across different species show sexual dimorphic effects on behavior. For example, the parenting behavior of female prairie voles is more dependent on OT, whereas male parenting behavior is more associated with AVP [54]. Furthermore, there are gender differences in OT receptor binding depending on the brain area and the species. For instance, female prairie voles show higher binding of OT receptors in the medial prefrontal ��-Sitosterol ��-D-glucoside chemical information cortex compared to males [55]. Higher OT receptor binding was found 23727046 in the hypothalamus of female rats compared to male rats [56]. Altogether then, it is not surprising that in the current investigation we observe a gender-specific relationship between plasma OT levels and the level of trust and marginally trustworthiness observed in the trust game. In “All’s Well That Ends Well” Shakespeare advised “Love all, trust a few, do wrong to none”. This sage 223488-57-1 web advice recognizes the inherent risk of betrayal embodied in bestowing trust [57,58,59]. The TG is designed to measure trust but its measurement is confounded by the element of risk since we must also consider that trust is not reciprocated [60]. To minimize the confounding aspect of risk inherent in the TG, we also assessed 15755315 subjects’ risk attitude using a portfolio choice design [25]. The use of this design allowed us to decompose trust and achieve a more refined estimate of an individual’s trusting behavior by minimizing potential confound of risk proneness or risk aversion. Our experimental design shows that plasma OT is reflecting trust and not risk attitude, as there appears to be no 
significant relationship between this hormone measure and risk. However, we are aware of the potential confound of trust and trustworthiness with other prosocial behaviors including altruism and inequity aversion [61]. As a consequence, our.Nce more likely to trust in the TG. Similarly, subjects with high plasma OT indicating increased social sensitivity and motivation would also show enhanced trust/trustworthiness driven by the warm glow of positive social interactions incurred in participating in the TG. There is a large body of literature in evolutionary biology on gender differences regarding reproduction and investment cost towards offspring [51]. As females usually incur higher costs for reproduction including giving birth and raising offspring, it is suggeseted that females will increase their fitness (number of viable offspring) by investing heavily in fewer children but insuring their the survival. On the other hand, males would increase their fitness by accessing to the maximum number of females they can mate with since the male investment in child bearing and rearing is lessPlasma Oxytocin and Trustthan the female. The behavioral consequences of gender difference in reproduction are unclear. It is, however, possible that these different investment strategies could lead to different psychological mechanisms towards trust and trustworthiness but also different biological mechanisms underpinning these two constructs for each of the sexes. In our findings, although the relationship between plasma OT and trust related behavior is significant in the pooled sample, separate analysis by gender revealed that the effects are more specific to the male side. This is in agreement with a large number of animal studies suggesting that OT differentially affects females and males, likely reflecting the interactions between OT and gonadal hormones [52,53]. Indeed, the effects of neuropeptides across different species show sexual dimorphic effects on behavior. For example, the parenting behavior of female prairie voles is more dependent on OT, whereas male parenting behavior is more associated with AVP [54]. Furthermore, there are gender differences in OT receptor binding depending on the brain area and the species. For instance, female prairie voles show higher binding of OT receptors in the medial prefrontal cortex compared to males [55]. Higher OT receptor binding was found 23727046 in the hypothalamus of female rats compared to male rats [56]. Altogether then, it is not surprising that in the current investigation we observe a gender-specific relationship between plasma OT levels and the level of trust and marginally trustworthiness observed in the trust game. In “All’s Well That Ends Well” Shakespeare advised “Love all, trust a few, do wrong to none”. This sage advice recognizes the inherent risk of betrayal embodied in bestowing trust [57,58,59]. The TG is designed to measure trust but its measurement is confounded by the element of risk since we must also consider that trust is not reciprocated [60]. To minimize the confounding aspect of risk inherent in the TG, we also assessed 15755315 subjects’ risk attitude using a portfolio choice design [25]. The use of this design allowed us to decompose trust and achieve a more refined estimate of an individual’s trusting behavior by minimizing potential confound of risk proneness or risk aversion. Our experimental design shows that plasma OT is reflecting trust and not risk attitude, as there appears to be no significant relationship between this hormone measure and risk. However, we are aware of the potential confound of trust and trustworthiness with other prosocial behaviors including altruism and inequity aversion [61]. As a consequence, our.