Testosterone has been associated with a wide range of behaviors. Digit ratio (2D:4D), a somatic marker of prenatal testosterone, has been associated with risk taking, but the findings are inconsistent. The present study sought to investigate an interactionist model combining biological and personality factors in explaining risk taking. Power has been previously found to moderate the relationship between 2D:4D and risk taking. It has also been suggested that optimism plays a mediating role in the relationship between power and risk taking. In light of these interconnections, the present study explored the interaction between 2D:4D and optimism as a predictor of self-reported risk taking. Two hundred and eleven participants (102 men and 109 women) completed self-report measures of optimism and risk taking, and their prenatal testosterone was estimated by left and right 2D:4D ratios. Moderated regression analysis showed that optimism moderated the association between left 2D:4D and general risk taking, with men and women taking more risk with lower 2D:4D and lower optimism levels. Further moderated regression analysis, including participants’ sex, revealed that optimism moderated the association between right 2D:4D and financial risk taking, but only in women, exhibiting more financial risk taking with lower 2D:4D but higher optimism levels.
KeywordsRisk taking Testosterone 2D:4D Optimism
Compliance with Ethical Standards
Conflict of Interests
Efrat Barel has no conflict of interest in the conduct and reporting of the research.
The study was approved by the institutional review boards (IRBs) of the Max Stern Academic College of Emek Yezreel. "All procedures performed in the study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards".
Informed consent was obtained from all individual participants included in the study.
The present manuscript has not been previously published or simultaneously submitted elsewhere.
- Aiken, L. S., & West, S. G. (1991). Multiple regression: Testing and interpreting interactions. Newbury Park: Sage.Google Scholar
- Dreber, A., & Hoffman, M. (2007). Risk preferences are partly predetermined. Mimeo: Stockholm School of Economics.Google Scholar
- French, J., & Raven, B. (1959). The bases of social power. In D. Cartwright (Ed.), Studies in social power (pp. 150–165). Ann Arbor: Institute for Social Research.Google Scholar
- Geschwind, N., & Galaburda, A. M. (1987). Cerebral lateralization. Cambridge: MIT Press.Google Scholar
- Hayes, A. F. (2013). Introduction to mediation, moderations, and conditional process analysis. New York: The Guilford Press.Google Scholar
- Manning, J. T. (2002). Digit ratio: A pointer to fertility, behavior, and health. New Brunswick: Rutgers University Press.Google Scholar
- Mehta, P. H., Josephs, R. A., (2010) Testosterone and cortisol jointly regulate dominance: Evidence for a dual-hormone hypothesis. Hormones and Behavior, 58(5), 898–906.Google Scholar
- Nettle, D. (2004). Adaptive illusions: Optimism, control and human rationality. In D. Evans & P. Cruse (Eds.), Emotion, evolution and rationality. Oxford: Oxford University Press.Google Scholar
- Powell, M., & Ansic, D. (1997). Gender differences in risk behaviour in financial decision-making: An experimental analysis. Journal of Economic Psychology, 18(605), 628.Google Scholar
- Rosvall, K. A., Burns, C. B., Barske, J., Goodson, J. L., Schlinger, B. A., Sengelaub, D. R., & Ketterson, E. D. (2012). Neural sensitivity to sex steroids predicts individual differences in aggression: Implications for behavioural evolution. Proceedings of the Royal Society B: Biological Sciences, 279, 3547–3555.PubMedCrossRefGoogle Scholar
- Tiger, L. (1979). Optimism: The biology of hope. New York: Simon & Schuster.Google Scholar
- Zethraeus, N., Kocoska-Maras, L., Ellingsen, T., von Schoultz, B., Hirschberg, A. L., & Johannesson, M. (2009). A randomized trial of the effect of estrogen and testosterone on economic behavior. Proceedings of the National Academy of Sciences of the United States of America, 106, 6535–6538.PubMedPubMedCentralCrossRefGoogle Scholar