Biological Psychology Links

Women who report feeling stressed early in their monthly cycle were more likely than those who were less stressed to report more pronounced symptoms before and during menstruation, according to a study by researchers at the National Institutes of Health and other institutions. The association raises the possibility that feeling stressed in the weeks before menstruation could worsen the symptoms typically associated with premenstrual syndrome and menstruation. Women who reported feeling stressed two weeks before the beginning of menstruation were two to four times more likely to report moderate to severe symptoms than were women who did not feel stressed. Premenstrual syndrome (http://www.nichd.nih.gov/health/topics/menstruation_and_the_menstrual_cycle.cfm.)is a group of physical and psychological symptoms occurring around the time of ovulation, which may extend into the early days of menstruation. Symptoms include feelings of anger, anxiety, mood swings, depression, fatigue, decreased concentration, breast swelling and tenderness, general aches, and abdominal bloating. "We were interested in identifying factors that might predict who might be most at risk for having more severe symptoms," said Audra Gollenberg, Ph.D., a postdoctoral fellow in NICHD's Division of Epidemiology, Statistics and Prevention Research. "It may be possible to lessen or prevent the severity of these symptoms with techniques that help women to cope more effectively with stress, such as biofeedback, exercise, or relaxation techniques."

By Emily Sohn When a woman is ovulating, her behavior changes in a startling number of ways from the way she walks, talks and dresses to the men she flirts with, according to new research. The findings might offer some practical tips for women to boost their online dating prospects; for scientists to develop new kinds of ovulation detection kits; or for marketers to target sales of clothes and jewelry. The work also suggests that going on or off the birth control pill might influence a woman's choice in men. Why does ovulation change women's behavior in such subtle yet fundamental ways? Experts propose that it's an innate and subtle strategy to both attract the most desirable guys and convince them to stick around for the long haul. "The idea is that women turn up everything that has to do with femininity" at ovulation, said Greg Bryant, an evolutionary psychologist at the University of California, Los Angeles. "This is showing that there are all sorts of phenomena that happen in our behavior that we're not actually aware of." For a long time, scientists assumed that the hormonal shifts of ovulation happened without measurable changes in how women behaved. That's because women have a strong motivation to hide the fact that they're fertile, unlike other members of the animal kingdom. While a female baboon's swollen red rump encourages males to mate and go, for example, a female human's ability to keep a man guessing should up the chances of him mating and then staying to help take care of their children. © 2010 Discovery Communications, LLC.

By Jenifer Goodwin (HealthDay News) -- Menstrual cramps are often dismissed as a mere nuisance, but new research suggests the monthly misery may be altering women's brains. Researchers in Taiwan used a type of brain scan known as optimized voxel-based morphometry to analyze the anatomy of the brains of 32 young women who reported experiencing moderate to severe menstrual cramps on a regular basis for several years, and 32 young women who did not experience much menstrual pain. Even when they weren't experiencing pain, women who had reported having bad cramps had abnormalities in their gray matter (a type of brain tissue), said study author Dr. Jen-Chuen Hsieh, a professor of neuroscience at the Institute of Brain Science at National Yang-Ming University in Taipei, Taiwan. Those differences included abnormal decreases in volume in regions of the brain believed to be involved in pain processing, higher-level sensory processing and emotional regulation, as well as increases in regions involved in pain modulation and regulation of endocrine function. Exactly how the changes in the brain could affect women's experience of pain is unknown, researchers said. But the brain abnormalities suggest that menstrual pain may have similarities with other chronic pain conditions in that over time, repeated bouts of excruciating aches make the brain unusually sensitive to pain -- in effect, making the experience of pain worse. ©2010 Bloomberg L.P.

Women are more likely to select clingy clothes when they are ovulating, a study has found. But the University of Minnesota study of 100 women found these hormonal shopping habits were triggered by the proximity of attractive women. The researchers suggest in selecting tighter clothes, the women were trying to stand out from love rivals. The Journal of Consumer Research study said there should be more analysis of how hormones affected shopping habits. Women at different stages of their menstrual cycle were shown images of attractive women living locally or far away. They were then asked to choose clothes and accessories which they would like to buy. Women who were ovulating and who had seen photos of attractive local women were most likely to buy "sexier" clothes compared with those shown photographs of unattractive local women or women who lived more than 1,000 miles (1,600km) away. Dr Kristina Durante, who led the research, said: "The desire for women at peak fertility to unconsciously choose products that enhance appearance is driven by a desire to outdo attractive rival women. If you look more desirable than your competition, you are more likely to stand out." The team said even though the end result was about attracting the best romantic partner available, ovulating women's choice of dress was motivated by the other women in their environment. (C)BBC

By Janet Raloff Cash register and other receipts may expose consumers to substantial amounts of bisphenol A, a hormone-mimicking chemical that has been linked with a host of potential health risks, according to a trio of recent studies. Each study offers preliminary evidence that a large number of retail outlets print sales receipts on certain types of heat-sensitive, or thermal, paper that use BPA as a color developer. Two of the new studies also showed that the BPA coating easily rubs off onto fingers. And one found evidence that BPA from receipts may penetrate skin. The pollutant, which mimics the biological activity of estrogen, has been tied to health risks from behavioral problems in children to obesity and heart ailments. In animals, exposures in the womb put moms and their offspring at risk for later metabolic diseases. Based on growing concern about possible risks from ubiquitous exposure to BPA, especially in children, the federal government recently issued warnings to parents about where their families were most likely to encounter the chemicals. Store receipts did not make the list, although there have been hints for years that thermal receipt paper could be a rich source. Chemist John Warner learned about the chemistry of thermal- and pressure-sensitive papers while working for Polaroid years ago. Manufacturers lay a powdery coating containing BPA, a dye and a solvent onto one side of a piece of paper. When heat or pressure is applied, the coating’s constituents merge to release the ink’s color, he explains. © Society for Science & the Public 2000 - 2010

By Susan Milius WILLIAMSBURG, Va. — Putting a female lemur on birth control turns her normally informative scents to nonsense, researchers report. Doses of Depo-Provera, a common contraceptive for people, shift the odor secretions of female lemurs so dramatically that their scents no longer give clear cues to kinship, identity and genetic quality, says study coauthor Christine Drea of Duke University in Durham, N.C. A female lemur whose hormones are disrupted by contraceptives may have real trouble attracting a compatible mate, Drea said July 26 at the annual meeting of the Animal Behavior Society. As for people, men and women might not think they’re influenced by each others’ scents, but “Oh, we are!” said behavioral biologist Susan Jenks of the Sage Colleges in Troy, N.Y., after Drea’s presentation. If women react to the hormones the way lemurs do, “maybe you don’t want to be on contraceptives when you’re picking your mate.” Also, said behavioral ecologist Jill Mateo of the University of Chicago, “For any zoo that is chemically contracepting animals, this could have big implications.” Drea and her colleagues have identified more than 300 compounds in the scent secretions of female lemurs. “There is a rich communication system,” she said. Glands on the forelimbs, tail and other parts of the body secrete chemical cues that the lemurs rub onto branches or other community bulletin boards, where neighbors sniff out the news. © Society for Science & the Public 2000 - 2010

By THE NEW YORK TIMES Dr. Dodick — I have been getting non-aura migraines since childhood, around the time my menstrual cycle began. I cut out caffeine, chocolate and red wine in my mid-20s but continue to have migraines once a month in conjunction with my cycle. I am curious if taking a birth control pill that limits the number of periods will also lessen the frequency of migraines? Lauren, Austin Dr. David Dodick of the Mayo Clinic responds: Menstruation is a very common and powerful trigger in women who suffer from migraine. There is evidence — and it has certainly been my experience with patients — that in some women, these attacks are also more severe and last longer than those attacks that occur outside the menstrual period. By definition, attacks of migraine that are triggered by menstruation occur within two days prior and three days after the onset of menstrual flow. While the mechanism by which menstruation triggers migraine is not completely clear, experts believe that the precipitous drop in estrogen levels prior to menstruation leads to changes in the excitability of the central nervous system, including the regions of the brain that are involved in migraine. The answer to your question is yes, for some women, there is evidence that taking a combination oral contraceptive pill continuously does reduce the frequency of migraine attacks associated with menstrual periods. However, you should discuss the risks and benefits of this strategy with your primary care physician or gynecologist. Copyright 2010 The New York Times Company

by Andy Coghlan NASAL sprays containing the hormone oxytocin, nicknamed the "cuddle chemical" because it helps mothers bond with their babies, have helped people with schizophrenia. Although the 15 participants used the sprays for three weeks only, most reported measurable improvements in their symptoms in this the first trial to test oxytocin in schizophrenia. "It's proof of concept that there's therapeutic potential here," says David Feifel at the University of California in San Diego, head of the team running the trial. Each participant received oxytocin or a placebo for three weeks, then the opposite treatment for three weeks with a week break in between. On the basis of two standard tests for schizophrenia, taken before and after each block of treatment, participants averaged improvements of around 8 per cent when taking the oxytocin compared with the placebo (Biological Psychiatry, DOI: 10.1016/j.biopsych.2010.04.039). The effects didn't kick in until the final week, suggesting that it takes a while for the hormone to begin acting. "Standard antipsychotic drugs increase their efficacy several weeks later too, so oxytocin fits that profile," says Feifel. Feifel thinks that oxytocin is dampening down the excessive production of the neurotransmitter dopamine, which can trigger schizophrenic symptoms such as hallucinations. © Copyright Reed Business Information Ltd.

Genetic engineers, move over: the latest scheme for creating children to a parent’s specifications requires no DNA tinkering, but merely giving mom a steroid while she’s pregnant, and presto—no chance that her daughters will be lesbians or (worse?) ‘uppity.’ Or so one might guess from the storm brewing over the prenatal use of that steroid, called dexamethasone. In February, bioethicist Alice Dreger of Northwestern University and two colleagues blew the whistle on the controversial practice of giving pregnant women dexamethasone to keep the female fetuses they are carrying from developing ambiguous genitalia. (That can happen to girls who have congenital adrenal hyperplasia (CAH), a genetic disorder in which unusually high prenatal exposure to masculinizing hormones called androgens can cause girls to develop a deep voice, facial hair, and masculine-looking genitalia.) The response Dreger got from physicians and scientists who were outraged over this unapproved use of dexamethasone caused her to dig deeper into the scientific papers of the researcher who has promoted it. The result of that digging is a discovery that is much less outrageous than the PR push, and some media coverage, would have you believe, but one that nonetheless raises important questions about gender, sexuality, and research on unknowing patients. In an essay titled “Preventing Homosexuality (and Uppity Women) in the Womb?” and posted on the bioethics forum of The Hastings Center, a think tank in Garrison, N.Y., Dreger and her colleagues pluck numerous brow-raising statements from the writings of pediatric endocrinologist Maria New of Mount Sinai Medical Center in New York, who has long promoted prenatal dexamethasone to treat CAH. But if that position is controversial (as I’ll explain below), what Dreger and her colleagues claim to have uncovered is even more so. New, they say, wants to use dexamethasone to prevent CAH girls from becoming lesbians, from rejecting motherhood, and from choosing traditionally masculine careers. © 2010 Newsweek, Inc

by Eliza Strickland When the housing market crashed in late 2008, most people were surprised by the sudden collapse. John Coates was not among them. He had spent 12 years trading derivatives for New York’s biggest banks—and had left finance for neuroscience, studying what happens in the brains of traders who put billions of dollars on the line in risky financial decisions. Coates, who now studies neuroscience and behavioral economics at the University of Cambridge, has made the London stock market his laboratory. His experiments seem to show that a trader’s success may be determined not by his wits but by the hormones that course through his brain. Hormone-fueled decision making can have powerful effects, intensifying market booms and busts and destabilizing the economy, Coates suggests. The markets’ operations are determined by legions of young men governed by confidence-boosting testosterone and the stress-related hormone cortisol. When hormones spiral out of control, economic behavior can do so as well. How did you get inside the heads of the people working in the financial markets? In our first experiment, we were on a trading floor in London with 250 traders, of which only three were women; the average age was maybe 28. They traded in and out very quickly, which means they would hold positions for minutes or even seconds. They would spot a price anomaly and jump on it, then quickly unwind. And they would make trades of huge value —$1 billion or $2 billion at a crack. We wanted to find out what was going on in the brains and bodies of these men who were taking such huge risks. So we collected saliva samples from the traders to measure their levels of testosterone and cortisol in the morning and the afternoon, bracketing the bulk of the day’s trading. Our hypothesis was that when traders had above-average testosterone their profits would go up, and in fact that’s exactly what we saw. It turned out that their morning testosterone levels were actually predicting their afternoon profits.

By Elizabeth Cooney Adam Davis says one of his brightest friends makes the most ridiculous mistakes. For all his smarts, he’ll cross the street without looking. “I know some people who are heavy drinkers, and they’ve actually told me they feel their memory is going. They drink and then they black out, more and more,’’ said Davis, a 20-year-old Lexington High graduate who attends Occidental College in Los Angeles. “They don’t change their behavior. I don’t think it’s addiction. I guess that gets into judgment.’’ Smart kids doing stupid things: It’s the teen brain paradox. Extraordinarily quick to learn and rapidly reaching fluency in abstract thought, teens still make bonehead decisions, perhaps more so when routines relax in summer. But that’s because they’re operating with brains that are still a work in progress. Of all the organs in our bodies, the brain takes the longest to develop. Frontal lobes — the seat of judgment — are the last pieces to be fully connected to the parts of the brain that sense danger or solve calculus problems. A growing body of neuroscientific evidence places full brain maturity at about age 25, well past the point when young people begin to drive, drink, vote, or go off to war. “We all know what the frontal lobe does,’’ said Dr. Frances Jensen, a neurologist at Harvard Medical School and Children’s Hospital Boston. “It’s insight, judgment, inhibition, self-awareness, cause and effect, acknowledgment of cause and effect. And big surprise: It’s not done in your teen years. Hence [teens’] impulsiveness, their unpredictable behavior, their lack of ability to acknowledge and see cause and effect, despite the fact they are getting 800s on their SATs and can be cognitively highly functional and memorize at a much more impressive rate than we as adults do later.’’ © 2010 NY Times Co.

Changes in the rhythmic action of the body producing Melatonin may be why the elderly don’t sleep as well according to study published in the February 2002 edition of the American Journal of Physiology--Endocrinology and Metabolism Bethesda, MD – Getting a good night’s sleep can become more difficult with age. Survey studies have shown that up to one-third of older individuals report difficulty maintaining sleep on a recurring basis and more than one-half report occasional problems with their sleep. The depth and continuity of sleep changes with age because there is a lower percentage of sleep spent in the deepest stages of non-REM sleep, there are more frequent arousals and awakenings during the sleep episode, and the inability to sustain sleep for the desired duration frequently occurs. Copyright © 2002, The American Physiological Society

Older men with higher testosterone levels performed better on tests of cognition in a new study from UCSF researchers. The study suggests that older men who are prescribed testosterone supplements may reduce their risk of cognitive decline, a precursor state to Alzheimer’s disease, the researchers said. Men’s bodies tend to produce less testosterone as they age, and some doctors have begun prescribing supplements of the hormone to increase libido and treat other age-related problems in men. “The men in the study with higher levels of bioavailable testosterone, the testosterone that can reach the brain, did significantly better on these cognitive tests than men with lower levels,” said lead author Kristine Yaffe, MD, UCSF assistant professor of psychiatry, neurology and epidemiology and biostatistics, and chief of geriatric psychiatry at SFVAMC.

Hormones have long been considered the solo act that molds brains along gender lines. But in recent years, hints that certain genes on the sex chromosomes might also play a role have been emerging. Now, new research points to the first structural brain difference between male and female mammals attributed to genetics alone. Sex hormones, in particular testosterone, help shape the developing brain of fetuses and newborns. Testosterone, secreted by the gonads, makes male brains distinct from female ones, and it is thought to account for difference in behavior and brain structure. A group of scientists, though, has wondered for years whether genes on the X and Y chromosomes have a hand in shaping brain differences. To find out, neuroendocrinologist Arthur Arnold at the University of California, Los Angeles, collaborated with colleagues in the United Kingdom who had genetically altered mice. Robin Lovell-Badge and Paul Burgoyne, developmental geneticists at the Medical Research Council’s National Institute for Medical Research in London, performed a genetic sex change. By using mice with a deletion in their Y chromosome for a gene called Sry, which kick-starts testes development, they ended up with XY “females” that had ovaries; adding Sry to the genomes of females generated XX "males" with testes. Although these mice had fully developed sex organs, both groups had fertility problems due to the gene manipulations. Copyright © 2002 by the American Association for the Advancement of Science.

New study may have implications for millions in search of the elusive “good night’s sleep” (Bethesda, MD) -- In movies and novels alike, much is made of the stage of sleep known as rapid eye movement (REM), since this is the phase of slumber in which dreams (good, bad, exotic) occur. Among the medical community, there is an increased appreciation for what is called “slow-wave” sleep, (also known as deep or delta-wave sleep), because this fourth stage of sleep can be difficult to attain. If one is awakened during the first three stages of sleep, they must repeat these stages again before reaching fourth stage or “delta-wave,” sleep. Once this latter stage is reached, muscles are relaxed, blood pressure drops, and the pulse and breathing are slower. According to the Sleep Research Center, other benefits to the body are accrued during slow-wave sleep, including: an increase of blood supply to the body; a decrease in body temperature thus preserving energy; a lowering of metabolic activity enabling tissue repair and growth; an increase of natural immune-system modulators; and a period in which the growth hormone secretions reach their peak, thus stimulating body growth and development. Copyright © 2003, The American Physiological Society

ST. PAUL, MN -- Women who consume little or no caffeine, but who take hormone replacement therapy, may reduce their risk of developing Parkinson’s disease, according to a study published in the March 11 issue of Neurology, the scientific journal of the American Academy of Neurology. However, HRT may increase disease risk in women who drink the equivalent of more than five cups of coffee per day. Two large studies have previously shown that increased caffeine intake is associated with a lower risk of Parkinson’s disease in men. Studies in women, which to date have not factored in use of hormone replacement therapy, have been contradictory and inconclusive. Parkinson’s disease is less common in women, and some evidence suggests that estrogen may help protect the neurons that degenerate in this disease. Estrogen is the principal hormone in HRT, a common therapy in post-menopausal women.

ST. PAUL, MN - The supplement dehydroepiandrosterone, or DHEA, which has been touted by some as an anti-aging hormone and a treatment for diseases such as cancer, AIDS, diabetes and Alzheimer’s disease, showed no effect for Alzheimer’s disease patients who took the supplement for six months, according to a study published in the April 8 issue of Neurology, the scientific journal of the American Academy of Neurology. DHEA is a hormone produced naturally in the adrenal glands. The body then converts it into the hormones estrogen and testosterone. DHEA as a supplement is made from plant chemicals. In the first randomized, double-blind trial of DHEA for Alzheimer’s disease, researchers gave 58 Alzheimer’s patients either 100 mg per day of DHEA or a placebo. Before the study began and at three and six months, the patients were tested for cognitive functioning and rated by physicians and caregivers on any changes in the severity of the disease.

Older men with lower levels of free, or unbound, testosterone circulating in their bloodstreams could be at higher risk of developing Alzheimer’s disease (AD) than their peers, according to research conducted by investigators at the National Institute on Aging (NIA), one of the National Institutes of Health, and others*. This prospective observational study is believed to be the first to associate low circulating blood levels of free testosterone with AD years before diagnosis. The study appears in the January 27, 2004 issue of the journal Neurology. “Our finding that low free testosterone might be associated with an increased risk of developing of AD is a step forward in helping to understand the possible effects of sex hormones on the aging brain and other parts of the body,” said Susan Resnick, Ph.D., an investigator in the NIA’s Laboratory of Personality and Cognition and corresponding author of the study.

Giving people a whiff of a key chemical can make them more inclined to trust strangers with their cash, a new study reveals. Just three puffs of a nasal spray containing a hormone called oxytocin increased the chance that people would part with their money. The research centred around a game in which an “investor” player gives part or all of his money on blind trust to an anonymous “trustee” player who earns interest on the combination of his own money and the invested sum. But the investor is told there is no obligation for the “trustee” to give any money back at all - they risk losing any money they choose to invest. Michael Kosfeld at the University of Zurich, Switzerland, who led the study found that investors gave away their money far more willingly if they had sniffed oxytocin than if they had sniffed a placebo. But this extra willingness disappeared when the trustee’s role was computerised, rather than carried out by another human, confirming that the effect was interpersonal, and not simply a general willingness to gamble. Kosfeld speculates that the hormone reduces people’s aversion to betrayal, overcoming an unwillingness to initiate interaction with strangers. This matches observations in animal studies. “It helps animals to approach one another, which is a parallel with trust in our game,” he says. © Copyright Reed Business Information Ltd.

An emotional buffer zone in the brain may not be working as it should in women who experience premenstrual moodiness, a new study suggests. David Silbersweig and colleagues at the Weill Medical College of Cornell University, New York, US, used functional magnetic resonance imaging to scan the brains of 12 women whose moods remained steady throughout their menstrual cycles. From 1 to 5 days before menstruation, and 8 to 12 days after, the women’s brains were scanned as they were shown printed words with either negative, neutral, or positive connotations – words like “rape”, “cancer”, “bookcase”, “rotate”, “gentle” and “delighted” – to engage the emotion-processing part of the brain. At the same time, the women were motivated to complete a simple cognitive task. The scans showed that the orbitofrontal cortex – part of the brain involved in controlling emotions and regulating motivation – was more active during the task in the days before menstruation. After menstruation, that part of the brain was relatively inactive during the task. Silbersweig says that the difference in brain activity may “buffer” hormonal changes in these women, helping them to maintain a consistent emotional state. “Because this area is kicking in, these women are able to avoid moodiness,” he says. © Copyright Reed Business Information Ltd.

Links for keyword: Hormones & Behavior