The hormonal sea

Ask any woman how she feels about her life at any time and if she indulges you, you would probably revisit what you thought was a simple question. Most likely, she would not give you a tidy linear string of one thing after another but a sea of "things" — an intricate weave of facts that are intimately tied to the tides of her emotions — all the ebbs and flows, the torrents and the calm sways. You get involved with a woman in any way and you are in for the sail of your life. And no, women do not come into your life accompanied by their own individual tidal mood chart schedule so that you can plan your life festivals like you do according to the phases of the moon. But there are guidelines so that you do not seem like you have a bull’s-eye chart drawn all over you, especially if you are a man living with a woman seasonally armed with hormonally charged darts.

I have heard women get deeply offended when their moods are linked to their menstrual cycles as if taking a feminist stance alters one’s biology enough to be impervious to the known linkages between menstrual cycles and moods. I think it is a futile exercise to dilute biological fact with this kind of feminist bravura. Women and men are made differently — parts-wise, process-wise and proportion-wise. Science has uncovered enough evidence to make a case for the biological differences between men and women and if you still cannot accept that, retake your biology classes or please let me know who your biology teacher was. However, it is another story to assume that it is these biological differences that would determine the kind of moral and professional choices we make. Biology is not the all-fulfilling basis for who we are and who we become. But it IS part of the equation, part of the story.

And the story continues to unfold. This time, from the findings of a recent study published in the Proceedings of the National Academy of Sciences of the United States of America last Feb. 13, vol. 104, no. 7 2465-2470. The study was entitled Menstrual cycle phase modulates reward-related neural function in women by Jean-Claude Dreher, Peter J. Schmidt, Philip Kohn, Daniella Furman, David Rubinow, and Karen Faith Berman of the Section on Integrative Neuroimaging and Behavioral Endocrinology Branch, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, Bethesda, MD.

The researchers wanted to see what exactly happens in the brains of women during two distinctly different stages in their menstrual cycles when they are presented with a situation where they anticipate an "uncertain" reward ("uncertain" because the reward will depend on certain conditions and also, the subjects were simply told they will get a "percentage" of the dollar bills they will see on the slot machines with no definite percentage mentioned) and are given the reward. The experiment involved women in the pre-ovulation stage or midfollicular phase (days 4–8 after onset of menses) and women in the post ovulation stage or luteal phase (6–10 days after luteinizing hormone surge). The experiment also involved men for the control group.

Why were the scientists interested to do this? They cited previous studies in animals where the reward system in the brain is tied up to their reproductive cycles. Meanwhile, what is known is that the "reward" system in the brain is mainly involved in behaviors such as addiction, particularly to drugs. In fact, they have observed rodents to give in to cocaine addiction during their pre-ovulation stage. The researchers wanted to see if they could link human ovarian hormonal levels and what it does to the "reward" centers of the brain.

The two menstrual phases mentioned, are like the flow and ebb of a woman’s inner sea. The flow is the surge of that hormone estradiol (an estrogen) as a woman approaches ovulation. After ovulation, comes the ebb of estrogen, which is not so much its decrease but its melding with another hormone called testosterone. During the "flow," estradiol surges unopposed by testosterone. Both hormones are synthesized mainly from cholesterol and are derived at different stages of the synthesizing process that involves different kinds of enzymes.

The findings have shown that for the times when "flowing" women were anticipating the reward, there was increased activity in the orbitofrontal cortex and the amygdala — two regions that are anatomically and functionally connected to be responsible for autonomic control (those we do not need to think about in order to perform such as swallowing, breathing etc.) and emotions. And for the times when they were handed the reward, the "flowing women," the caudate nuclei, midbrain region, left amygdala, and left fronto-polar cortex showed that they were the "rides" that were active if your brain were a theme park. All these "rides" that light up from reward anticipation to reward delivery are all part of the brain network called "reward system." This "reward system" seems to be the best non-technical collective term the scientists could come up with to describe the parts of your brain that light up when you desire something that makes you feel good, regardless of cost. "Desire" is emotional and "cost" is rational. For the "ebbing women," these parts still did light up although less than that of the "flowing women’s." I remember the humorist Dave Barry writing once that since the caudate nuclei (one of the brain parts that light up in flowing women) is responsible for our ability to think in terms of relationships, he suspected that women have one the size of a melon and men have one the size of a peanut. "Flowing women" are more emotional about anticipating a reward and getting it than they are at the ebb phase in their menstrual cycle. The researchers think that this, in part, may explain why women are more vulnerable to addiction when the temptation presents itself during the "flow" phase. So for those who think that PMS (ebb phase) is the only slippery slope you have to be careful while treading a woman’s sea, it might be a good idea to redo your charts.

Now, if you think that women are too much work, it may help for you to think of what women have to face. Women live out their ebbs and flows all their lives while puzzling over historically problematic creatures called men who call themselves "rewards." And you still ask us why we seem to see bull’s eye instead?

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