The Science of Trust

From The Science of People

Imagine that you are working at a coffee shop and you have to run to the bathroom. You look at the person sitting next to you and wonder if they will watch your computer while you're gone.

Can you trust them?

You decide to trust someone in 33 milliseconds.


Well, I should say your brain decides if you should trust someone in only 33 milliseconds. Trust is a fascinating human behavior. It can help us answer the following questions:

  • Why do people cheat?
  • What's the difference between a push-over and a cold-hearted bastard?
  • Are women really nicer than men?

  • For you, I decided to uncover 9 facts about: The Science of Trust

    For our Science of People book club we read The Moral Molecule: How Trust Works by Paul Zak, and I wanted to share with you my favorite little nuggets from the book and some broader facts about trust.

    9 Trust Hacks to Improve Your Relationships


    How do you get people to trust you more? How can you tap into and optimize your own trust intuition? Let me explain how trust works:

    #1: The Trust Molecule


    A single molecule controls our trust--it is called Oxytocin.You know that warm and fuzzy feeling you get when you just feel really good about someone? That's oxytocin! Researcher Paul Zak has pioneered some of the latest research on the power of this single molecule.

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    As humans, we are constantly battling 2 internal forces:

  • To be open and trusting to build happy-making relationships
  • To be hesitant and cautious to protect ourselves from potentially toxic people
  • Oxytocin is the chemical regulator of these two desires. It is also the hormone that controls our empathy, morality and connection.

    Rule of Thumb: The more you feel connected to someone, the more oxytocin you have pumping in your body.

    #2: Oxytocin Pays


    Having more oxytocin has tons of benefits. Researchers found that when people are given a nasal spray of the hormone oxytocin, they behave in ways that are kinder, more compassionate, cooperative and generous.

  • You connect with people faster
  • Your relationships are stronger
  • You earn more money

  • Let me dig into this last one a bit more. Zak carried out an experiment called the Trust Game. In this ultimatum game, one of two people is given a sum of money and told she must decide how to split it with person No. 2. If person No. 2 is dissatisfied with the split, then she can reject it, but then the money vanishes, and neither person gets any. Zak found that participants with higher oxytocin levels shared and then earned more money than low oxytocin players. When researchers gave some participants a squirt of oxytocin beforehand, their offers increased by 80%. In other words, trust is a better way to approach a deal than competitiveness.

    This is reflected in country data as well--in economies with more trust, there is higher GDP.

    "Being able to rely on others to deliver what they promise and not cheat or steal, is a more powerful factor in a country's economic development than education, access to resources--anything." -Zak

    #3: Oxytocin Loves


    Oxytocin is how we bond and build loving relationships. Oxytocin can deepen all kinds of relationships in your life:

  • You can be a better parent
  • You can be a better friend
  • You can be a better lover
  • In a set of terrifying experiments on animals, researchers inhibited the oxytocin levels in mothers and found that those mothers then shunned their offspring. On the other hand, when mothers were given higher oxytocin levels, they were better at nurturing their young AND began to nurture other mother's offspring as well. This is why nursing dogs occasionally adopt orphaned kittens:

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    Why is oxytocin so important for love and relationships? Zak argues that displays of generosity is the number one rule for courtship in human societies.

    "Who wants a mate who's going to be selfish and self-interested?" - Zak

    So, we produce oxytocin in a healthy relationship to make us more compassionate AND we look for people with high oxytocin when searching for a good relationship.

    #4: Why We Commit


    Researchers have done lots of experiments on prairie voles -- they tend to have monogamous relationships like humans. Researchers wanted to see if they could tempt prairie vole husbands.

  • Researchers took virgin male meadow voles--the ones who are loners and playboys and injected them with oxytocin
  • Then, they paraded the playboy male voles in front of a line of attractive, single female prairie voles.
  • After the voles had sex with their choice, instead of running off to another vole, the male stayed to cuddle and nest with that same female over and over again (even when presented with other perfectly attractive female voles at the ready).

  • Yes, you read that right. Oxytocin made them want to cuddle.

    This suggests that oxytocin might be a major factor in a man (or woman's) desire to nest -- and be monogamous.

    Special Note: Oxytocin is nicknamed the cuddle hormone. To test this out, I did this cuddle experiment:

    click to view

    Interesting Fact: Oxytocin surges for everyone after a wedding! Zak took blood from all guests at a wedding ( yes, really! ) and found that happiness for the couple causes an oxytocin bonanza. Even more crazy--you can predict how much oxytocin is released based on the person's closeness to the bride!

    #5: Why You're Lonely


    Could your oxytocin levels change your social behavior? Specifically:

    Are you a loner?

  • Researchers created a "knockout mouse" where they removed the gene for oxytocin from the mouse's genetic code.
  • This mouse suddenly produced zero oxytocin and subsequently developed social amnesia. He couldn't recognize other mice who'd been longtime pals and he became a loners in his cage.
  • When researchers injected this mouse with oxytocin, the social amnesia disappeared!

  • If you feel anti-social or have a hard time connecting, there could be a chemical explanation. Some research has even found a link between oxytocin levels and autism .

    Special Note: One of the studies I found fascinating in the book had to do with childhood trauma. People who have experienced trauma as a child, have lower oxytocin levels and have lower oxytocin responses. Trauma somehow inhibits our feelings of empathy. This is easily understood: If someone was abused, their brain and body learns that people can't be trusted and therefore shuts down production of the trust hormone. This is why victims of abuse have a very hard time connecting with people and might be avoidant of future relationships. This might even be the cause of Oxytocin Deficit Disorder . Their body is trying to learn from the past.

    #6: Women Are Nicer Than Men


    ... at least in the Trust Game. The average amount returned by a male player in the trust game was 25%. The average returned by a female player was 42%! On the extremes, 30% of the men returned less than 10% (pretty skimpy), but only 13% of the women were that coldhearted. The ultimate snub: 24% of the men returned absolutely nothing (took everything for themselves), while only 7% of women did so. Researchers believe this has to do with a man's testosterone which is an oxytocin blocker.

    "The higher the testosterone, the more the oxytocin response is blocked, the less empathy a person experiences. The less empathy a person experiences, the less generosity they have." -Zak

    A possible explanation for this could be that when male cavemen were hunting for food they had to have more testosterone to help them on the hunt. They had to have less empathy to kill and skin their prey to feed their family back in the cave.

  • It's Not All Women: Zak was able to test Stephanie Castagnier, known as "the goddess of greed" on the Apprentice. Castagnier watched a heart-wrenching video depicting a child dying of cancer. While this made most participants oxytocin levels surge by 47%, Castagnier's oxytocin increased only 9%. Castagnier came from a traumatic childhood--her father was a high-rolling drug dealer and became a homeless junkie when she was young. Before she had finished high school, both of her parents had died of AIDS. See note on trauma above--this tends to inhibit natural oxytocin responses.
  • Let's get back to the men. I'm going to put it all out there with this scary fact:

    "High-testosterone males divorce more often, spend less time with their children, engage in competitions of all types, have more sexual partners (as well as learning disabilities) and lose their jobs more often." -Zak

    Wowser. I was happy to direct quote Zak on that because that research is a doozy. But don't worry, there are ways to produce more oxytocin than your natural baseline:

    #7: Oxytocin Triggers


    Since we now know that oxytocin helps us earn more money and more love, let's talk about what triggers oxytocin.

    Not all of us can get oxytocin nasal sprays for our friends and family = )

  • Emotional Videos: Even watching emotional or heart warming clips can increase your oxytocin--47% on average over people's baseline according to Zak!
  • Touch: Handshakes, fist bumps, high fives, hugs--they all produce oxytocin. Never skip a handshake, because that initial touch upon greeting sets you up for a stronger connection as your oxtocin begins to pump.
  • Tweeting: Sometimes connection can happen in the digital world too. Zak did a rather unscientific study with Fast Company writer Adam Penenberg and found that after tweeting, his oxytocin increased by 13%! I want to make a special note here: I think this only works if you truly feel you are building relationships and connecting with followers.
  • Dancing: Zak did a study with swing dancers and found that after busting some moves, oxytocin levels raised on average (across age and genders) by 11%! Interestingly, Zak found that those who were more central to the social group of dancers had higher production of oxytocin.
  • Eye Contact: Mutual gazing is another way to increase oxytocin, which is one of the reasons eye contact is so important during networking.
  • Massage: Researchers found that players in the Trust Game who were given massages, had a 9% increase in their oxytocin levels immediately and were willing to give 243% more!
  • Laughter: Oxytocin is a very happy chemical. When you laugh with someone, your body triggers all kinds of bonding responses.
  • #8: Superhuman People Powers


    Oxytocin makes you better at reading people and helps us interpret what others are thinking--the ultimate mind-reading super power. In one study , participants given oxytocin were better at interpreting subtle social cues from the eyes and guessing what the person in a photograph might be thinking or feeling at that moment, compared to participants given a placebo.

    The better your people skills, the more oxytocin you produce and the deeper your connections are. In a big way, oxytocin is the entire reason I run this website. I want you to feel connected to the people around you, have deep meaningful relationships and be memorable to people around you.

    When you deepen your relationships, you produce more oxytocin.

    Learning how to interact with people is the ultimate oxytocin producer.

    #9: The Virtuous Cycle


    "Oxytocin generates the empathy that drives moral behavior, which inspires trust, which causes the release of more oxytocin, which creates more empathy. This is the behavioral feedback loop we call the virtuous cycle." -Zak

    We are human because we care. If you see someone in distress, your brain releases oxytocin so you can help. We can't survive without fellow humans, and we have adapted to encourage connection, survival and strong support systems. This is why we are driven to help those around us--in the short term it benefits them, and in the longterm it benefits us all.

    Bottom line: Nice guys finish first.