By Michelle Koidin Jaffee
New research by University of Florida neuroscientists suggests that male and female sex hormones may play differing roles in risk-taking inclinations and the ability to delay gratification.
The findings from two separate rodent-model studies, reported in the journals Neuropsychopharmacology and eLife, could provide useful insight for development of future treatment approaches for psychiatric conditions such as substance use disorders, the researchers said.
As reported in Neuropsychopharmacology, a team led by Barry Setlow, Ph.D., and Caitlin Orsini, Ph.D., examined the regulation of risky decision-making by sex hormones in male and female rats. Previous work from the Setlow lab showed that females tend to be more risk-averse than males, and the new study finds that the presence of estradiol, a form of the female hormone estrogen, decreases risk-taking in both females and males.
In the eLife study, a team led by Jennifer Bizon, Ph.D., and Caesar M. Hernandez, Ph.D., reported that male rats preferred more delayed gratification than female rats. Removal of sex hormones caused male rats to prefer more immediate gratification, but had no effect in female rats. An inability to delay gratification — or to choose a smaller, immediate reward rather than demonstrate an ability to wait and receive a bigger reward — has been linked to some psychiatric conditions.
“The work in these two papers shows that impulsivity and risk taking are regulated differently in males and females,” Setlow said. “This suggests in turn that approaches to treatment — for example, reducing impulsivity or risk taking in substance use disorders — could differ in men and women.”
The next step in this line of research, Setlow said, is to examine the contributions to risk taking and impulsivity of additional types of gonadal hormones, such as progesterone and dihydrotestosterone, and how all of these hormones influence the brain to ultimately bias choice behavior.