Psychological research suggests that individuals vary greatly in the degree they are willing to take risks. Despite the intensive research on risk taking, the neurophysiological mechanisms of risk behavior are still poorly understood. Moreover, most studies on this topic are conducted on men and focus on risk seeking. We believe that in order to redress this balance, it is important to explore the mechanisms of risk aversion, with a particular focus on women. This project aimed to explore the psychological and physiological antecedents of risk aversion. More specifically, we aimed to link differences in hormone levels with individual risk preferences, taking into account differences in temperament, affect and cognition.  Other studies show that reward sensitivity is linked to testosterone levels, and we hope that our further analyses will be able to support this link and extend this analysis to other hormones that we studied, e.g. cortisol and vasopressin.

Methodology

In this project we conducted a series of four larger studies.

In Study 1 we adapted research methods to study risk taking and conducted a series of small behavioral studies aimed at exploring the relationship between risk attitudes and cognitive, affective and temperamental characteristics. The main objective of Studies 2 and 3 was to study relations between risk taking and hormone levels in men and women.

The levels of reproductive hormones estradiol and testosterone, as well as the levels of oxytocin, vasopressin and cortisol were measured in multiple samples taken during the entire menstrual cycles (in women, Study 2) and during one month sampling period (in men, Study 3). A follow-up Study 4 addressed the issue of sex differences in risk taking in relation to reproductive hormone levels and hormonal and electrophysiological markers of stress response.

In addition, we used computational modeling to understand better the sources of the behavioral effects that we observed.

The data analyzed so far allowed us to conclude that the often observed relationship between gender and risk – women less willing to take risks than men – is not universal.

In a study on prisoners and non-prisoners, in a sample with balanced gender proportions, we observed that female prisoners and equally or even more willing to take risks as male prisoners and men from the general population. In addition to behavioral data, we used computational modeling which allowed us to elucidate the possible psychological sources of the observed effects.

Female prisoners, as well as male prisoners and the men from the general population, were characterized by high sensitivity to rewards when making decisions under risk, possibly neglecting the negative consequences of their behavior.