She’s a contradiction in heels: fearless one day, weepy another, and keenly intuitive every day in-between. Dr. Louanne Brizendine, author of The Female Brain and founder of The Women’s Mood and Hormone Clinic in San Francisco, says that a woman’s unique hardwiring and hormonal makeup can turn her into a different creature with every passing day and decade. Here are seven things men should know about how women’s brains work.

1. She’s hottest during one week of the month.

About 10 days after a woman’s period is finished and a few days before ovulation—that mid-cycle time when her body is most fertile—it’s no secret that her libido revs up. “As a woman’s estrogen and testosterone levels increase during the week before she ovulates, her sex drives also rises,” says Louanne Brizendine, M.D.. What’s surprising is that this estrogen peak also causes physical changes designed to make her a man magnet: A woman’s voice becomes slightly more high-pitched and she becomes more turned on by the pheromone scents that men naturally emit. PS: Later in a woman’s cycle as she gets within three days of her period, her sex drive is at its lowest and she is prone to tears and irritability—otherwise known as PMS.

2. She’s not being rude when she cuts you off.

Pair two gal pals over brunch together, and even without a mimosa in hand, they’ll usually create an immediate gabfest—complete with non-stop talking and completing each other’s sentences. “When females talk to each other,” says Brizendine, “they often engage in overlapping speech. But when a woman interrupts her man, it can shut him down.” The point: While we should voice and respect one another’s communication needs, Brizendine encourages men not to take this female habit too personally. There’s no hormonal cause for this tendency, says Brizendine, but, she adds, “Scientists believe it has to do with a difference in our brains” (women’s brains usually process language rapidly) and the difference in our socializations (it’s socially acceptable for women to openly share their emotions with one another).

3. Her focus shifts during the final part of her pregnancy.

We know, we know: While she’s prego, a woman goes on a roller-coaster of emotional and physiological changes—from a brain that can become up to 4 percent smaller and progesterone increases that make her feel exhausted during the first trimester. But there’s an often-overlooked change that occurs about one month before delivery, says Brizendine: “A woman starts some nesting behavior—she prepares the baby room, the bassinet, the clothing.” She says the particular mix of progesterone and estrogen at the final stage of pregnancy causes this shift in mothers—”and when men start feeling a little left out,” adds Brizendine, “they should remember that it’s a natural hormonal response.”

4. Yes: Perimenopause eventually does pause.

Brizendine calls a woman’s second puberty “a rock n’ roll for the hormones”—that time when everything from mood and sex drive to even sensitivity to caffeine and alcohol changes rapidly. “Men write to me all the time and say, ‘What happened to my wife?”‘ says Brizendine. “I assure them that this transition won’t last forever.” Perimenopause can last anywhere from two to nine years; for the average woman, this stage begins between 44 and 45 and ends between 52 and 55. The key word that men should cling to, says Brizendine: “Patience!”

5. She copes with hard times differently than you do.

“In stressful situations, the female tactic is to ‘tend and befriend’—in other words, she makes friends with other women as a way of protecting herself,” says Brizendine. So when, say, a woman worries that she’ll lose her job in this recession, she may begin reaching out to her network of girlfriends for support, reassurance, to trade ideas and information, and to form alliances. Conversely, stress generally triggers the fight or flight response in males, who tend to get more aggressive when they’re stressed or when there’s an unstable hierarchy at work. “It’s not that either approach is superior,” says Brizendine. “Men and women just have different ways of protecting themselves.”

6. She has a unique internal GPS system.

While study after study has shown evidence that males usually fare better at reading maps and distinguishing direction than females do, don’t count out the Girl Scouts just yet: Women tend to navigate using landmarks and visual cues as their reference points—as in “turn left at the grocery store” or “make a right at the red brick house.” This gender difference may have evolutionary roots: Our male ancestors needed navigational focus in order to hunt for animals, while females used their big-picture awareness of their surroundings to stay on the lookout for fruits and berries they could gather. Says Brizendine: “Some evolutionary biologists believe this ability also has to do with how women would hide—and later relocate—their food sources.”

7. She’s a natural at reading your non-verbal cues.

Women’s intuition has a biological basis—the female ability to read and interpret emotional responses in others is directly tied to women’s natural role as caretakers. Over the course of human history, evolution has selected women for their competence at keeping their babies alive by reading their children’s non-verbal cues for, say, food and warmth. The ability to interpret another’s emotional state carries over into every other part of a woman’s life—including her relationship with her partner. “That’s why men often feel that women can read their minds!” says Brizendine. As it turns out, it’s just that women have centuries of practice at decoding facial expressions—and that keeps the female emote-o-meter in top condition.

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