Hormones and Handshakes: The Role of Oxytocin In Trust

by Roxanna Salim

Trust is a vital asset in the workplace and essential for leaders as they strive for sustainable business results. With trust, employees have a sense of confidence in their managers and commitment to their companies’ success. Without it, they lack engagement and productivity declines. Until recently, little was known about the neurological basis of trust among humans1. Over the last decade, a number of studies investigating the role of the hormone oxytocin in trust have shed light 
on the underlying mechanism of this important social construct (1,2,3,4). This blog highlights some of that evidence and some possible ways of strengthening trust in the workplace.

Oxytocin is a hormone that plays an important role in a number of processes such as reproduction, birthing and maternal bonding. In fact, oxytocin is often called the “bonding hormone”. It is present when humans experience stress and may stimulate a desire to connect socially with others. More recently it has also been linked to processes such as social recognition, cultural behaviors, empathy, and not surprisingly, trust. The two effects of oxytocin, under conditions of stress and when trust is present, help us understand how stress and trust building can be leveraged to create tremendous positive impact in the workplace.

Paul Zak PhD, Director of the Center for Neuroeconomics Studies at Claremont Graduate University, and his colleagues have found that oxytocin is released in response to social signals of trust and trustworthiness (1,2,3). They have found this across a number of studies by examining the reactions of participants during monetary 
decision-making games. In one study, they presented pairs of participants with an economic trust game in which they interacted only through a computer program without face-to-face contact or direct communication (1). Players were each given an account with $10 that was theirs to keep for participating in the game. They were asked to transfer their money between accounts during the game. Player one was asked to send player two a sum of money from their account at their discretion and both players were informed that any money sent to player two would be tripled in player two’s account. Player two was then asked to send back money to player one. After each decision, the level of oxytocin was measured via a blood test. The researchers measured the degree of trust by the amount of money player one gave player two and looked at the relationship between this “giving” and oxytocin release. They found that oxytocin increased as levels of giving increased (1). Conversely, when trust (as indicated by the amount given) was low, they found that the oxytocin response diminished in both players (1).

This finding suggests that oxytocin release is not only affected by signals of trust, but that signals may vary based on “how much” we trust an individual. This principle has significant application to the workplace: Are we happier and more productive when we trust our coworkers? Do we give more effort when a high degree of trust in our team is present? Zak’s team extended their research to investigate these questions. They studied a group of employees performing work-related tasks while collecting biological data such as heart rate, stress responses and oxytocin release (4). The group also presented employees with a survey of organizational trust that asked about numerous workplace practices including giving unexpected praise, setting clear goals and demonstrating concern for others, all of which have been shown to lead to increases in oxytocin (4,5). Results from this study suggest that employees who scored higher on the test’s organizational trust scale had greater increases in oxytocin release during the tasks and also reported greater joy and higher levels of productivity while at work (4).

So what does this mean for business leaders? Our neurobiology is doing everything it can to help us connect to each other and when we are better connected we are more likely to be engaged not only with each other but also in the work and the mission we are trying to accomplish. We can leverage these benefits by recognizing when we can help each other during times of stress and when we do that we take action to deepen the degree of trust. According to Zak, we can do things such as clearly communicating goals to create a sense of purpose among employees, which boosts trust and lowers stress (4). We can also work diligently to build trust by being trustworthy, being consistent and clear in our actions, and by involving people in decisions that affect them. More handshakes and the hormones that conspire to connect us can lead to better business outcomes.


1. Kosfeld, M., Heinrichs, M., Zak, P.J., Fischbacher, U., Fehr, E. (2005). Oxytocin increases trust in humans. Nature, 435, 673-676.

2. Zak, Paul (2008), The neurobiology of trust. Scientific American, 298, 88-95.

3. Zak, Paul (2012). The Trust Molecule. The Saturday Essay, Wall Street Journal.

4. Zak, Paul (2014). Take a Little Oxytocin and Call Me in the Morning. The Moral Molecule. Penguin Group Publishing, New York, New York.