Archive for May 15, 2013

High T and Love Juice

In the summer of 1981 when I was 30, a strange and embarrassing thing happened to me.  In a group room at the Massachusetts Mental Health Center, where I had just started my residency in psychiatry, as one person said her ritual goodbyes to the circle of over 25 patients and clinicians, most of them strangers to me, I cried.   The cry washed through me, quiet but strong enough to bend my head, soak my cheeks, and run my nose—I did my best to stuff it and later to dismiss it.

My lapse only took on meaning when it happened again in other group meetings, and then at graduations and then watching corny commercials.  What was this–my initiation into professional empathy?  None of my classmates were losing it this way.  All too soon I went from being a guy to being a guy who cries over good-byes and commercials.  And I had no clue about why.

Last night, 32 years later and still the easy weeper, I got a new clue.  Thinking about all the forces that separate us from those we love—geographic distance, poor communication, fear, poverty, prejudice, illness, fatigue, bad weather—it’s amazing most of us stay attached in some way.  It’s amazing how driven we are to stay attached, sometimes even to those who mistreat us.  Staying attached trumps comfort and sometimes safety.  We’re made to connect and, with a few select people, to stay intimately connected.

Call it attachment, call it love.  Last night I learned about a new contributor to this tethering force, affectionately referred to by the Northwestern anthropologist Lee Gettler as “T” for testosterone.   Gettler and colleagues recently did what no one before them had done: they collected testosterone levels on a sample of 624 men age 21  and again 5 years later, along with information at both times about courtship, partnership, fatherhood, and childcare habits.

“High T,” it turns out, favors our chances at that age of catching a partner, possibly by turning up the love juice.  Guys like hearing that kind of news.  We like to think more is better.  But the big news of the study may be harder to take: having babies drops our T by half.  And spending at least three hours a day changing diapers and playing peek-a-boo drops our T even more.

Here’s behavior reprogramming our biology. The same effect is true for birds and other beasts too.  But why?  High T gives us the edge in the chase for a mate, but high T also drives males to risky behaviors, such as more roaming and finding more mates, more fights, more drugs and alcohol.  It’s no accident that combat soldiers do their riskiest work in their early twenties, far from mates and babies.

When the birth of a baby drops the father’s testosterone, it’s easier for the father to stay closer to home.  And fathers with lower testosterone tend to be more moved by the cry of a baby, less moved by the movements of a tight skirt.

I’ve never had my testosterone level checked, but I find it enlightening to know that mine probably peaked in my 20’s and had been dropping for a couple of years when the easy weeping started.  Falling in love in 1977, marrying in 1978, having a son in 1979, and starting my residency in psychiatry in 1980 with daily challenges from my supervisors to “put one foot in the world” of my patients meant those years threw me into depths of intimacy I’d never imagined, demanding new kinds of love juice.  For guys, high T makes for a good chase, but lower T allows for loyalty, for tending to the toddler, for weeping with the griefs and joys of others.

Power to the Altruists

You’re on my mind when I remember how you pulled out of rush hour traffic to help that woman with a flat tire—surely a stranger to you and me both, while I and the rest of the highway commuters rushed by her.  I’ve been reading about you.  Now I understand.  Evolution made you do that.

Not the brutal evolution that I grew up with—not “survival of the fittest” and “competition drives selection” and the winner propagates while the loser dies.  Evolution may be a kinder, gentler process than we were taught, I recently learned through Martin Nowak, a professor of biology and mathematics, in his Scintific American article “Why We Help,” July 2012.  Nowak argues that cooperation plays as strong a role as competition in the natural selection process.  Altruism and seemingly random acts of kindness play a role in determining who lives and who dies, independent of whether you can overpower the next guy down on the pecking order.

I find that observation reassuring, because it affirms what I would prefer to believe about human nature—that we thrive both by winning and by helping.  Our species ought to be smart enough to have figured this out by now.  But the startling truth, according to Nowak and colleagues, is that we did not figure it out.  We inherited this adaptive trait, not just from our primate ancestors but from more primitive species before them.  In fact, this capacity to survive through cooperation as well as competition operates in every species studied so far, from amoebas to zebras to humans—moreso in humans because of our relative talents for communication.  “This universality,” Nowak writes, “suggests that cooperation has been a driving force in the evolution of life on earth from the beginning.”

Amazing.  How could we have missed this principle for the past 150 years?  Darwin was a smart guy. He missed it.  Most of his followers missed it too. In my biology courses we learned that evolution proceeded in a ruthless dog-eat-dog way. Good riddance to the runts of the litter.  We missed it because we weren’t looking for it, not in humans and not in lesser species.  We’ve been more impressed by the cruelty of nature than by its kindness.

But as a species, though we may be a bit slow, we’ve come a long way.  Some of us have evolved beyond subsistance living. For us, social fitness increasingly trumps physical fitness as a determinant of survival.  What makes humans more helpful and more cooperative than other species is our capacity to communicate, especially about who helps and who is connected to whom.  We thrive on altruism, or what Nowak calls “indirect reciprocity.” Think of Facebook as the most efficient form of reputation monitoring in our long history, but reputation monitoring (also
called gossip, politics, clubs, etc) has always been a defining feature of families and gangs and tribes—any group of people.  Altruism now reaches farther than ever.

If you doubt this assertion about the evolutionary value of cooperation as just some trick of mathematical modeling and game theory, which it also is, think more about Nowak’s five cooperative strategies for managing conflict, strategies that favor survival over many generations:

1)      Direct reciprocity—you scratch my back, I’ll scratch yours.  You feed me now, I’ll feed you tomorrow.

2)      Spatial selection—neighbors or clusters cooperate to prevail over individuals: block watch.

3)      Kin selection—helping relatives promotes some of your genes. Jennie’s Mom and Dad are strung out on cocaine, so Uncle Gene pays for her wedding.

4)      Indirect reciprocity—helping those who have a reputation for helping others: When Mother Theresa gets a flat tire, people line up for the privilege of helping her.

5)      Group selection—helping your tribe to prevail over other tribes: military enlistment.

The lesson for me from Nowak, who has built his career on this set of observations, is that, like natural selection, our daily lives proceed through a dance of competition and cooperation.  As Nowak says, “the employees of a company compete with one another to move up the corporate ladder, but they also cooperate to ensure that the business succeeds in its competition with other companies.” We mind our manners not only because we’re told to, but mostly because we’re made that way.  It’s in our genes to help others.  And you may gain as much or more from helping that stranger with a flat as I do from hurrying home to my eager wife.