Remarks by Paul Zak

Commencement Address by Paul J. Zak - Why are we here?©

Why are we here? Besides today's graduation, why are we at this university? Why do we live in cities? In a country with a freely elected government and a massive industrial economy? Research by my lab, the Center for Neuroeconomics Studies, and several other labs around the world are beginning to identify the neurophysiological processes that have led to the extraordinary success of the human species.

I will briefly report some of these facts to you, but I'll give you a hint of the punch line: it all boils down to family. Indeed, it is significant that many graduates today have gathered their families together with the CGU extended family to share this momentous occasion.

Our story begins 100 million years ago with fish living in primordial oceans. Nature had to manufacture a way that fish could at most times be fearful of other fish who might eat them for dinner, but allow some conspecifics, at some times, to get close enough for sexual reproduction. Yes, our story starts with fish sex! Sex is important because it permits greater species diversity and therefore adaptation to changing environments. The solution to the "how to get fish to have sex" problem was an ancient hormone called vasotocin. This hormone still facilitates fish reproduction.

Through millennia, this hormone was hijacked and modified for other purposes. Nature is conservative, and would rather modify a known mechanism than start from scratch with something new. One mammalian variant of vasotocin is called oxytocin. Oxytocin facilitates birth through uterine contractions, and initiates milk production for the feeding of offspring. In some mammals, such as prairie voles and humans, oxytocin also facilitates pair bonding. In these highly monogamous species, raising successful offspring is facilitated when there are investments from both parents. Researchers have recently demonstrated that the neural architecture utilizing oxytocin in monogamous vs. promiscuous mammals is different.

Monogamy actually changes your brain! Your brain is also changed by your earliest interactions with your mother. Mammals deprived of mother-love (or a suitable substitute), do not develop normal cognitive or social skills, are emotionally stunted, are sick more often and die younger. The first intimate relationship in your life is with your mother (can you think of any football players who say "Hi Dad" to the TV cameras?). The lateWisconsin psychologist Harry Harlow showed in the 1960s that baby monkeys strongly prefer a cloth-covered surrogate mother that provides no food to a wire-mesh surrogate with food. Similarly, human children crave parental love, for this literally constructs their minds. So, Fact 1 is that parental care is critical for brain development.

Oxytocin also permits us to "attach" temporarily to other human beings, even ones who we don't know. Nearly all humans (with the exception of sociopaths, most autistics, and others with severe mental disorders) feel empathy when they see others suffering. The standard biological view is that we should only care about those with whom we share a substantial number of genes. Clearly this is not how humans behave, and much of this is driven by oxytocin.

If you take two unrelated hungry rats and put them in a cage with food, typically a brutal fight will erupt until the dominant rat eats its fill. Yet hungry humans will queue (mostly) patiently at restaurants, sometimes for hours, without fights. More generally, the ability of humans to temporarily attach to each other permits us to live in large societies with other mostly unrelated humans. In fact, many of us like the excitement of living in big cities.

The oxytocinergic attachment mechanism was essential to the development of civilization in theFertile Crescent 10,000 years ago because it facilitated the formation of large-scale societies. Large societies permit individuals to specialize in tasks, become highly productive in these tasks, and generate surplus resources that can be used for investments in people and the creation of machines. More generally, Cort Pedersen at the University of North Carolina School ofMedicine has argued that the complexity of social living, enabled by human attachment mechanisms, is the evolutionary source of human intelligence. Recent work by my lab shows that human intelligence is strongly related the size of one's "social brain". These brain regions-the hippocampus and amygdala-are the only areas known to produce new brain cells in adult primates, including humans. Fact 2 is that oxytocin and social living arethe sources of human intelligence, and social intercourse rewires your brain, even as an adult.

Modern industrial economies require that groups of unrelated individuals work in the same location, take direction, mostly avoid violence, and forego current consumption to achieve future goals. We are a social species because our brain is designed for social tasks, tasks that often utilize neuroactive oxytocin. Cooperation in groups requires that we understand what other human beings are doing, and in particular, that we trust others.

Oxytocin is a "feel good" hormone, for example, rising during sex, while eating, and when one is caressed. My lab has recently shown that when a person observes that someone wants to trust him or her, oxytocin surges. More simply, people are trustworthy because it "feels right." It is not that we are selfless, but that we are designed to respond to social cues. My team also showed that humans are largely unaware of the neurologic response to social cues, but that they nonetheless affect our actions. Fact 3 is that oxytocin is part of our social guidance system that permits us to rapidly evaluate the trustworthiness of other people.

While trust affects us many ways in our daily lives, it also affects entire economies. In research published recently, I showed that poor countries are poor primarilybecause trust is low. Indeed, trust is among the most powerful factors affecting economic growth that economists have ever found. So, Fact 4 is that sufficient interpersonal trust is necessary to raise poor people's standards of living.

Trust levels fundamentally reflect the underlying social-political-legal and economic fundamentals of a society. My lab has also recently shown that biological factors in a country affect trust levels. For example, countries in which there is more socializing have higher trust. The biological jargon for this is "repeated non-noxious stimuli" raises oxytocin.

My group also found that environmental conditions that affect hormones influence trust levels. Countries with dirty environments--particularly those with an abundance of "xenoestrogens" (synthetic estrogen-like molecules such as are found in the pesticide DDT and many pollutants) have lower trust. (A bit more biology: roughly speaking, estrogen increases the uptake of oxytocin by brain cells, and estrogen antagonists do the opposite). We also find that the consumption of phytoestrogens (plant-based estrogens found in soy beans and other legumes, broccoli, tea, wine, and many other foods), is strongly related to trust. So, Fact 5 is that environmental conditions affect hormones, trust, and therefore the prospects for economic development.

OK, by raising trust we can help alleviate poverty--that's exciting. So, how do we do this? My team examined a variety of government policies that might raise trust. We find a number of policies raise trust by promoting positive social interactions, for example, by raising the number of telephones in a county. But, to be effective, such policies must raise incomes more than they cost to implement. We find only a few policies do this. Leading the pack is education. For the countries we analyze, it costs less than $500 per person to keep every child in school for an additional year. Because the effect of education on trust, and trust on income growth is so strong, average income will increase more than $2,500 per person if education increases by one year-that's a 400% return on investment! We also find that reducing income inequality is a cost-effective trust promoter, as are increasing civil liberties and freedom of association. So, Fact 6 is that trust levels respond to government policies, and most importantly, to education.

I began this talk by asking why we are here. We are here because humans are a nurturing and caring species. We are here because for generations as a species we have cared for the young, and cared for each other. As we celebrate today's graduates for their diligence and desire, we must also praise their parents for their important contribution to their children's success. If you remember one thing from today, I hope it will be this: We are truly designed to be our brothers' and sister' keepers, and in caring for others we make brains and indeed ourselves better, too.