Hormones and Intelligent Choices

Understanding hormones makes us smarter, but intelligence is still biological.

Posted May 04, 2018

At the NorthEastern Evolutionary Psychology Society (NEEPS) conference two weekends ago, I heard a familiar yet puzzling assertion: "We are not controlled by our biology. We are not automatons."

This idea was asserted by one of the keynote speakers, Martie Haselton, in her address, "The Hidden Intelligence of Hormones: How They Drive Desire, Shape Relationships, Influence Our Choices, and Make Us Wiser" (uncoincidentally, the title of her book that was recently published). Dr. Haselton, Professor in the Department of Psychology, Department of Communication Studies, and the Institute for Society and Genetics at UCLA, describes herself as "an interdisciplinary evolutionary scientist interested in how evolution has shaped the social mind" (follow this link to her website). She is an acknowledged expert on hormones and behavior. She is especially well-known for her painstaking methods for pinpointing when women are ovulating and for her research on how women's behaviors vary across the menstrual cycle.

Before explaining why I was puzzled by Dr. Haselton's assertion that we are not controlled by our biology, I'll review some of the highlights from her keynote address. I read her book after the talk and discovered, to my amazement, that her one-hour talk essentially summarized her entire book—an impressive achievement, in my opinion. Because the address paralleled the book, I will be quoting some passages from the book that represent what Dr. Haselton told us in her talk.

Dr. Haselton began her talk by questioning the way that the term "hormonal" is applied to women, but not men. She noted that hormone levels fluctuate in both men and women, and that different hormone levels are associated with different behaviors in both sexes. Contrary to this folklore that changes in hormone levels make women more erratic, impulsive, irrational, moody, muddle-headed, or unreliable than men, Dr. Haselton argued that hormones actually encourage women to behave in intelligent, adaptive ways. The idea that hormones encourage us to make bad decisions is simply inaccurate.

Dr. Haselton documented how this inaccurate view of hormones has been used for decades by both major political parties in the U.S. to cast doubt on the fitness of women to hold positions of power. Dr. Haselton reminded us how, after Fox News anchor Megyn Kelly questioned Trump about this behavior during a presidential debate, Trump told CNN reporters, "You could see there was blood coming out of her eyes, blood coming out of her wherever." But Dr. Haselton also recalled an event from the 1970s that many of us had forgotten or not even heard of. One of Vice President Hubert Humphrey's top advisors, Dr. Edgar Bergman (a member of the Democratic National Party's Committee on National Priorities), had claimed that women were unfit for leadership positions because of their "raging hormonal influences."

History tells us that men (and women) in both major political parties have claimed that a female president should not be trusted with the decision to launch a nuclear strike because her hormones will either deter her from taking tough action or will endanger us by calling for an unnecessary nuclear strike. Dr. Haselton noted the irony in worrying about women's hormones influencing decisions about nuclear strikes, given testosterone's influence on aggressive and risk-taking behavior.

But wait, you might ask. Is Dr. Haselton denying the existence of premenstrual syndrome (PMS), with its documented irritability and sometimes anti-social behavior? No, not at all. On page 21 of her book she says about PMS, "And if you really want to make a woman mad, tell her that her physical and emotional discomfort is just a figment of her imagination.") What Dr. Haselton suggests is that PMS may be a woman's intelligent strategy for driving away a partner who is not impregnating her. Here is her evolutionary reasoning, from page 80 of her book:

"If an ancestral woman was having regular sex with the same male for several cycles without getting pregnant, then perhaps he was infertile or they were somehow genetically incompatible with each other. (Cases of infertility can be traced to women or to their male partners, or they remain mysterious — suggesting that perhaps some couples are just not compatible with each other.) After a few months of this, as her period approached and then arrived, it makes sense that she would eventually reject him and seek out other options. In modern times, a woman's mate doesn't get her pregnant every time they have sex (fortunately), so as her period approaches, this otherwise acceptable person might seem unacceptable. The antisocial behaviors associated with PMS may have evolved to ward off males who could not facilitate reproduction — guys with no game, or gametes." (In both her talk and in her book, Dr. Haselton made it clear that this idea is just a hypothesis worthy of further research, not the final explanation for PMS.)

To the modern mind, this kind of "intelligence" might seem odd, to say the least. Many couples intentionally avoid pregnancy with contraception, so for a woman to become irritated with her partner because he fails to impregnate her appears to be the opposite of intelligent. What was missing in her talk and also her book, to my mind, was a clear delineation of two different kinds of intelligence. First, there is the evolved intelligence of the body, shaped by natural selection to deal with environmental opportunities and threats that have been common in human history. In this sense, it is intelligent for a woman to feel irritation toward a partner that fails to impregnate her.

But there is also a different kind of intelligence, based on a conscious understanding of the emotional impulses that nudge us toward typical, evolved strategies. This type of intelligence or awareness allows us to decide whether to follow through on an impulse or to choose a different course of action. (This is roughly what Daniel Kahneman refers to as "slow thinking" overriding "fast thinking.")

Up to this point, I am on board with everything that Dr. Haselton is saying. I agree that a woman's hormones do not lead to less intelligent decisions than a man's hormones. I've seen plenty of cases where testosterone led men to make some pretty stupid decisions. I daresay that this has happened to me. I also think that both women's and men's hormones mostly encourage intelligent action, but that an understanding of hormonal influences on behavior leads to a higher level of intelligence where we can consciously decide whether the follow through on nudges we get from our hormones.

The one sticking point I have with Dr. Haselton's position is when she refers to the capacity for conscious intelligence as "free will." Here is what she says on page 204 of her book: "In searching for the existence of human estrus and confirming that it is real, we've also discovered that women evolved so that they would not be under strict hormonal control, so that they'd have free will, so that they'd be able to make strategic choices that would benefit their individual lives, if not choices that would perpetuate their genes." And further, on page 233, "Women can think logically and make rational decisions every day . . .  . This is because we are not under strict hormonal control, locked in the sway of 'heat,' weakened by loss of blood, or depleted as our fertility fades. . . . In my view, every girl and woman benefits from understanding the scope of hormonal cycles, the hows, whens, and whys. We should become familiar with the potential nudges that affect our behavior. And we should know that choosing to act on those behaviors is an individual choice, dependent on our own preferences and goals."

This brings us back to the assertion Dr. Haselton made at the conference that puzzled me, "We are not controlled by our biology. We are not automatons." Despite all of the terrific insights that Dr. Haselton shared with us, I wanted to shout back, "Yes I am controlled by my biology! I am an automaton. We are all biological automatons!"

Why do I say this? I have a longish explanation in a previous blog post. A shorter explanation begins with a question: What exactly is this "I," this decision-maker who chooses whether to act upon a hormonal nudge, if not some aspect of my brain, which is a biological organ? In what sense is so-called "free will" not a part of biology? And if you want to bring up "environmental" effects on us, I would point out that many—perhaps most—of them (e.g., food, drugs, medicines, hormonal treatments, infectious diseases, other human beings) are biological entities that interact with our own biology.

I understand that, historically, expressions such as "biology is destiny" have been used to justify unfair discrimination against individuals on the basis of gender and race. But to fight such discrimination by claiming that people have a "free will," a ghost in the biological machine that somehow transcends biology, chemistry, and physics is to take an unscientific path. When we don't give in to a hormonal nudge, it is because some other aspect of our biological nervous system makes that choice, not because there is an "I" that is free from biology. Understanding how our biology makes those choices is what a truly scientific psychology is about. And the better your scientific understanding of your biology, the better able you will be to make intelligent decisions.