To Trust or Not to Trust: Ask Oxytocin
When someone betrays us, how does the brain deal with it? A hormone associated with social attachment gives us clues.
The development of trust is an essential social tool, allowing people to form productive and meaningful relationships, both at a professional and personal level. Bonds of trust are also extremely fragile, however and a single act of betrayal—such as a marital affair—can instantly erase years of trustworthy behavior. The consequences of such breaches in confidence can be disastrous, and not only for a relationship. People who have been betrayed in the past will sometimes start avoiding future social interactions, which is a potential precursor to social phobia. In light of these connections, recent research has attempted to elucidate the neural mechanisms underlying trust behavior. This is the goal of an exciting new study by neuroscientist Thomas Baumgartner and colleagues at the University of Zurich in Switzerland that combines different disciplines (economics and neuroscience) and methodologies (neuroimaging and neuropharmacology) to investigate how the brain adapts to breaches of trust.
The Chemistry of Trust
To study social interactions, economists, and more recently neuroscientists, take advantage of a simple game played between two people called the “trust game.” (For more on greed and altruism, see this.) In a typical trust game, an investor (Player 1) is faced with a decision to keep a sum of money (say, $10) or share it with a trustee (Player 2). If shared, the investment is tripled ($30) and the trustee now faces the decision to repay the trust by sending back a larger amount of the initial investment (for example, $15 for each participant) or to defect and violate trust by keeping the money. In this game, the investor is therefore left with an important social dilemma: to trust or not to trust. Although it is more profitable to trust, doing so leaves the investor at risk of betrayal.
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