Hydrocortisone reduces altruistic punishment in healthy men.

Psychosocial stress modulates social cognition and behavior in humans. One potentially mediating factor is cortisol as part of the human endocrine stress response. With a double-blind, placebo-controlled between-subject study design, we tested possible dose-dependent effects of hydrocortisone (0 mg, 5 mg and 20 mg) in 85 healthy males. During a socio-economic decision-making task we measured trust, trustworthiness, sharing, punishment, and non-social risk behavior. Social value orientation (SVO) was also assessed. We observed significantly lower levels of punishment after hydrocortisone, especially in the 20 mg group. Drug-induced salivary cortisol correlated negatively with punishment behavior. None of the other facets of social behavior or the SVO were affected by hydrocortisone. Our results suggest that hydrocortisone reduces the propensity to punish unfair behavior. Future studies are needed to further disentangle the role played by various psychobiological mechanisms within the stress response as well as their complex interplay on social behavior and cognition.

Effects of menstrual cycle phase and ovulation on the salivary cortisol awakening response.

The cortisol awakening response (CAR) is influenced by several state and trait variables, one of which might be the menstrual cycle in women. Previous results suggested that the CAR is enhanced around ovulation, which is why it has been recommended to avoid sampling during the ovulatory phase. In two separate studies, we aimed to replicate previous findings that reported the CAR's modulation across the menstrual cycle, especially during ovulation. In Study 1, a group of 27 healthy naturally cycling women collected saliva at 0, 30, 45, and 60 min post-awakening on two days during their follicular, ovulatory, and luteal phases in a repeated measures design. In Study 2, CAR samples were collected from 30 healthy naturally cycling women on seven consecutive days around the expected ovulation. To increase reliability of CAR measurements, participants' compliance of saliva sampling times was monitored, ovarian steroids (estradiol and progesterone) were collected, and ovulation was confirmed with specific test kits. Contrary to our expectations, we detected no differences in the CAR over the menstrual cycle, and no significant association with variations in estradiol and progesterone. In addition, we excluded confounding effects such as compliance and validated the cycle phase. These results suggest that the CAR is largely robust against hormonal variations across the menstrual cycle, including the mid-cycle phase around ovulation. However, further research is needed to understand the potential ovarian steroid-induced modulation of HPA axis functioning and the menstrual cycle's effects on salivary cortisol levels in psychobiological studies.

The modulation of social behavior and empathy via oral contraceptives and female sex hormones.

Oral contraceptives (OC) and endogenous female sex hormones in naturally cycling women (NC) are related to a wide range of psychological variables (eg, cognition and affect). Little research on social behavior has been done. One study documented a tendency towards more prosocial behavior in NC than OC women, but the underlying neuroendocrine mechanisms remain unknown. The sex hormones progesterone and estradiol are potential candidates. We analyzed social decision-making and social behavior in 83 healthy women (38 OC and 45 NC) via the Social Value Orientation (SVO) and in real social interactions within a paradigm adapted from behavioral economics. We also measured empathy, and collected saliva samples to quantify the basal levels of estradiol and progesterone. Our analyses revealed higher levels of prosocial behavior and emotional empathy in NC than in OC women, a finding supported by higher levels of prosocial decisions in NC than OC women in the SVO. Regarding the underlying biological mechanisms, we detected lower progesterone levels in OC than NC women. Exploratory analyses revealed a negative correlation between progesterone and trust on the trend level. We found no correlations between estradiol and behavior. Our findings provide evidence that OC modulate social behavior and initial indications of a possible modulation by progesterone. Further research is needed to replicate our findings and extend them to other social behaviors.

The effects of acute stress and stress hormones on social cognition and behavior: Current state of research and future directions.

Stress encompasses profound psychological and physiological changes that are observable on all levels, from cellular mechanisms, humoral changes, and brain activation to subjective experience and behavior. While the impact of stress on health has already been studied for decades, a more recent field of research has revealed effects of stress on human social cognition and behavior. Initial studies have attempted to elucidate the underlying biological mechanisms of these stress-induced effects by measuring physiological responses or by using pharmacological approaches. We provide an overview of the current state of research on the effects of acute stress induction or pharmacological manipulations of stress-related neuro circuitry on social cognition and behavior. Additionally, we discuss the methodological challenges that need to be addressed in order to gain further insight into this important research topic and facilitate replicability of results. Future directions may help to disentangle the complex interplay of psychological and biological stress variables and their effects on social cognition and behavior on health and in disorders with social deficits.