The Science of Trust
This is what trust looks like inside your head.
In the late 1930s, a teenaged boy named Ferdinand Waldo Demara, Jr. ran away from his family home in Lawrence, Mass., to embark upon an extraordinary career of deception that earned his the nickname "The Great Imposter." Over the next couple of decades, Demara managed to pass himself off as a college psychology professor, a Catholic priest, a high school teacher, and even as a Canadian Royal Navy surgeon who was trusted to perform delicate operations.
How did Demara, who had no qualifications for any of these jobs, manage to convince other people to believe in him and trust him with lofty responsibilities? Judging from photographs, Demara's biggest asset—besides his high intelligence and brazenness—may have been his appearance. The habitual con artist had a rounded, youthful-looking face with a broad mouth and chin, large eyes, and eyebrows that were relatively close together. Humans, as it turns out, often make snap judgments about who to trust based largely upon superficial characteristics of their faces—a practice may date back to prehistoric times, when early humans had to decide quickly whether a stranger to their pack was friendly or menacing.
And as it turns out, evaluating facial features generally is a fairly effective way to make a quick judgment about whether or not a person is worthy of trust. In a study by German and British psychologists, subjects did significantly better at picking trustworthy individuals by looking at their faces than they did by listening to recordings of their voices. But every so often, our visual shortcut to trust also leads us to put faith in someone who doesn't deserve it.
In this article, we'll look at the nature of trust—a quality that enabled early humans to cooperate for survival and eventually to form complex civilizations, and which today makes possible everything from married relationships to high-stakes business deals. Though it's an integral part of human existence, the perceptual and neurological mechanisms related to trust are just starting to be understood by scientists. We'll explore those processes and the cues that our brains use in deciding whether or not to trust someone. We'll also look at the limitations of our trust-evaluating system.
How Trust Happens in Your Brain
The ability to trust seems to emerge in the first year of life, when newborn infants have no choice but to trust their parents to feed and protect them.A study published in Psychological Science in 2010 found that three-year-olds generally trust whatever adults tell them verbally, even after a person repeatedly gives them information that turns out to be untrue."Children have developed a specific bias to believe what they're told," University of Virginia psychologist Vikram K. Jaswal explained in a press release. "It's sort of a short cut to keep them from having to evaluate what people say. It's useful because most of the time parents and caregivers tell children things that they believe to be true." A study published in 2003 by Austrian researchers, in which subjects had the option of trusting anonymous partners, found that the capacity to trust seems to increase throughout childhood, but then stays constant throughout a person's adult life.
The process by which trust occurs in the brain isn't yet well understood, but it appears to be pretty complicated. In experiment published in 2010 by Temple University researchers in which subjects' brains were scanned while they engaged in simulated business transactions, trust seemed to be related to higher activation in the caudate nucleus and anterior paracingulate cortex of the brain, and also to lower activity in the orbitofrontal cortex. Interestingly, when subjects distrusted someone, it lit up completely different areas of the brain, the bilateral amygdala and insular cortex.
But another important part of trust seems to be oxytocin, a hormone produced in the hypothalamus. By turning down the amygdala, the region of the brain that controls fear responses, and inhibiting the release of the stress hormone cortisol, oxytocin helps lubricate the mental processes that enable us to forge connections with other people.The brain chemical contributes to bonding between parents and their offspring, and between lovers, friends and coworkers.
Oxytocin promotes such a touchy-feely ambiance that in a study presented at the Society for Neuroscience conference in 2010 showed, subjects who received additional doses felt so much more connected to the society that they even paid rapt attention to those public service spots on TV.
But one of its most important functions is helping us to have faith in others. In a series of studies, many of them published in the scientific journal Nature, psychologist Markus Heinrichs of the University of Freiberg in Germany showed that subjects who received oxytocin felt greater trust in and empathy toward others, even as their anxiety and stress levels were reduced.
At the same time, conversely, oxytocin also seems to figure in helping us to be worthy of others' faith. In a study published in Journal of Neuroscience in 2012, University of Bonn researcher René Hurlemann found that when men in committed relationships were given doses of the hormone, they kept more distance between themselves and unfamiliar women. (Interestingly, the hormone didn't seem to affect single men.)
But while oxytocin amplifies our tendency to trust others, it doesn't actually influence our choice of who to trust. In a study published in Psychological Science in 2010, Belgian researchers found that after subjects received a nasal spray dose of oxytocin, they were more trusting of partners in a simulated investment game than a control group who received a placebo—as long as the partners appeared to be reliable. But the subjects who got oxytocin were just as reluctant to put faith in partners who seemed shady as the volunteers who weren't dosed with the chemical.
A Trustworthy Face and Mannerisms
Instead, it seems that the sections of the brain that engage in trust, and the chemical that facilitates that feeling, need to be switched on by the areas of our brain that process sensory information, in particular our visual processing mechanisms. In addition to watching a person's physical manner, we pay particular attention to his or her looks. "Humans seem to be wired to look to faces to understand the person's intentions," Princeton University Assistant Professor of Psychology Alexander Todorov explained in a 2008 article. The researcher, who has shown hundreds of different computer-generated variations of the human face to experimental subjects, has found that humans generally make split-second judgments about people based upon their facial features and expressions.
Research by Todorov and others has shown that we tend to put faith in individuals with comparatively more rounded faces, broader chins, wider mouths with upward-pointing corners, larger eyes and eyebrows that are closer together. Because those features seem to occur most often in brown-eyed people, trusted individuals also tend to have brown eyes, even though eye color—in the absence of those other characteristics--doesn't seem to exert an influence. Conversely, we're biased not to trust blue-eyed people, who tend to have faces that are smaller, pointier, longer, and feature eyebrows that are situated further apart. And the Israeli researchers discovered in a study published in 2012, a "baby face"—that is, features whose relative softness or roundness conveys youth—can make subjects more likely to trust a leader of an opposition group than if he had a face that appeared older.
In addition to reading someone's face, we utilize other physical mannerisms to evaluate the trustworthiness of someone. In a study published in 2012 in the journal Psychological Science, researchers from Northeastern University, Massachusetts Institute of Technology, and Cornell University had experimental subjects play an economic game with anthropomorphic robots who had been programmed to mimic humans' characteristic nonverbal mannerisms, such as crossed arms, leaning backward or shaking the head. The scientists found that when subjects could observe such cues, improved their ability to tell whether or not the robotic player should be trusted.
Scientists aren't sure exactly why we have these particular biases, but their effect is profound. In a study published in PLOS One in 2012, researchers showed subjects a series of faces on a screen and offered a chance to invest money with them. They found that the subjects were more willing to trust their money to people whose faces had features that we tend to associate with trustworthiness—even when they were given negative information about the prospective investment manager. As study co-author Chris Olivola from the University of Warwick's Business School explained: "It seems we are still willing to go with our own instincts about whether we think someone looks like we can trust them."
How Come We Get Fooled?
Trust is so powerful that it actually can alter memories to make them fit a belief. In a study published in Journal of Personality and Social Psychology in 2013, for example, researchers found that subjects who were highly trusting tended to remember their romantic partners' actions as being more considerate and less hurtful than they originally reported at the time they occurred. (People with a low capacity for trust, in contrast, tended to remember transgressions as being more severe than they actually were.) As one of the co-authors, Northwestern University psychologist Eli J. Finkel, explained: "One of the ways that trust is so good for relationships is that it makes us partly delusional."
Another problem is that when we're evaluating a person's trustworthiness, we tend to make that judgment on the basis of superficial details of their physical appearance, cues that necessarily provide accurate information. While we traditionally are inclined to trust people who confidently look us in the eye, for example, a study by University of California, Berkeley psychologists, published in Journal of Personality and Social Psychology in 2011, found that subjects who admitted a faux pas and showed signs of embarrassment—such as gazing downward while partially covering their faces—actually turned out to be more trustworthy, with higher reported levels of monogamy in relationships, and a tendency to behave more generously.
- Dr. Feelgood
- The Hug Drug
- The Love Hormone
- Monogamy Molecule
- Happy Potion
- Answer: The Love Hormone
- Meryl Streep
- Maya Angelou
- Denzel Washington
- Tom Hanks
- Sandra Bullock
- 1 Tom Hanks
- 2 Sandra Bullock
- 3 Denzel Washington
- 4 Meryl Streep
- 5 Maya Angelou
- 6 months
- 12 months
- 18 months
- 2 years
- 3 years
- Answer: 12 months
How To Be A Confidence Man (Or Woman)
Four ways to foster success by building trust.
In the Brain Games episode "Trust Me" we learned that humans have an innate tendency to put faith in others, and that we tend to make quick decisions about who to trust, often based upon visual cues such as the shape of a person’s face. While our credibility-evaluating mechanisms for the most part are surprisingly accurate, they’re also vulnerable to being manipulated by those who know how to subtly game the system, whether they’re advertising executives, job candidates or con artists. Here are some secrets on how to get what you want from others, which we hope that you’ll use for benign, non-illegal purposes.
Smile. This probably seems like a no-brainer, but as executive coach Carol Kinsey Gorman notes in a 2013 article for the American Management Association website, the human brain prefers happy-looking faces. "Smiling not only stimulates your own sense of well-being; it also tells those around you that you are approachable and trustworthy," she writes.
Lower your vocal pitch. Gorman also observes that speakers with higher-pitched voices tend to seem less empathetic, less powerful, and more nervous than those who speak in a lower register. She recommends using a simple exercise, in which you put your lips together and say "Um hum, um hum, um hum." This supposedly relaxes your voice and allows you to attain your optimal low pitch.
Use the "foot in the door" approach. In a study published in Journal of Personality and Social Psychology back in 1966, researchers discovered that if they approached a subject with a small request and got the person to agree, the person often subsequently would agree to a larger follow-up request as well.
Make an outrageous request, followed by what you actually want. In a study published in 1975, also published in Journal of Personality and Social Psychology, researchers found that if they asked subjects for an extreme favor and were turned down, the person often would comply with a subsequent request for a smaller favor. Persuasion experts call this the "door in the face" technique.