Naomi Wolf's Vagina Aside, What Neuroscience Really Says About Female Desire By Maia Szalavitz Getty ImagesThe controversy surrounding journalist Naomi Wolf’s new book, Vagina: A Cultural History — an exploration of the brain-vagina connection — has brought fresh attention to the nature and neuroscience of female sexuality. Unfortunately, it’s done so largely because Wolf profoundly misrepresents how the brain works and how neurochemicals like dopamine, oxytocin and serotonin really affect our love lives (as well as conditions like addiction and depression). Correctly understood, neuroscience offers important insight into how our minds function and how our brains shape our lives; many of my articles on Healthland attempt to explore these questions. But the kind of oversimplification seen in Wolf’s book and, sadly, in many other popular accounts of neuroscience, threatens to perpetuate a psychological myth. Rather than illuminating the complex interplay between mind and body, it portrays human beings — especially women — as automatons, enslaved by brain chemicals we cannot control. That’s not what the science shows. The mind-body connection is far more complicated and wonderful, as a quick tour through some of Wolf’s errors will illustrate. There is a new science of female sexual behavior, but it is far more liberating than the book suggests. (MORE: First 3-D Movie of Orgasm in the Female Brain) Let’s start with Wolf’s understanding of dopamine, a neurotransmitter that rightly fascinates many researchers. Dopamine appears to be critical for motivation and desire: if it’s depleted or blocked (with a medication like an antipsychotic, for example), people may lose the will to strive, even the ability to move. But boost it with a drug like cocaine and people feel capable, excited, empowered. Here’s how Wolf connects women’s sexuality with the function of dopamine in the brain: If as a woman, you are frustrated sexually and even worse, aroused but denied release, your dopamine system eventually diminishes in anticipation of sex, you eventually lose access to the positive energy you might otherwise have had both in sex and also subsequently to take elsewhere in your life … With low dopamine activation, you will suffer from a lack of ambition or drive, and your libido will be low. The theory sounds plausible, but “the fallacy is that she’s saying dopamine is primarily involved in sexual pleasure, and that’s not the case,” says Larry Young, a pioneering researcher on sexual and social bonding and co-author of The Chemistry Between Us: Love, Sex and the Science of Attraction. “Dopamine is involved in reward and motivation for everything we do in life — whether we’re eating good food, drinking good wine or interacting with our kids and family.” Sexual frustration, therefore, isn’t likely to turn off your dopamine system. “Taking one [type of pleasure] away isn’t going to change all aspects of your life like that,” Young says. He also points out that dopamine isn’t only associated with joyful experience. “It’s also released under stressful conditions,” he says. Further, if the dopamine system typically turned itself off when satisfaction wasn’t attained, few people would develop addiction. Indeed, the experience of addiction itself is marked by ongoing desire in the face of frustration: addiction doesn’t create an overall lack of desire or drive, but rather a very intense, if misdirected, motivational pull toward the drug of choice. (MORE: The Female Erotic Brain, Mapped) Wolf further misconstrues how dopamine interacts with serotonin, another neurotransmitter that has multiple functions, including roles in mood and sensation. Arguing that antidepressants that raise serotonin levels (like Prozac and other drugs of its kind) may be used to keep women submissive, she writes: Dopamine will — if women and their vaginas are not hurt, suppressed, injured or demeaned — make women more euphoric, more creative and more assertive — possibly more than a male-dominated society is comfortable with … Serotonin literally subdues the female voice, and dopamine literally raises it. Again, there is no basis in neuroscience for this claim. Although some antidepressants have the side effect of suppressing sexual desire, this affects both men and women, not women alone. Antidepressants that increase serotonin levels don’t typically deplete desire or motivation in general, however. Quite the opposite in fact: people whose depression has been lifted by these drugs tend to be more motivated, not less. Women are more likely to be depressed than men, so they’re more likely to take medication for it. And yet while some antidepressants work by elevating dopamine — for example, bupropion (Wellbutrin) — you don’t see women being denied such drugs for fear they’ll overthrow the patriarchy. As with all antidepressants, women are prescribed these drugs more frequently than men are. We still don’t know which medication will lift depression better — or worsen it, for that matter — in any given individual of either gender, though. The complexity of the condition and the widely varying response to antidepressants illustrate just how subtle and nuanced the interactions are between serotonin, dopamine and other neurotransmitters and our moods and desires. Countless things can go wrong to produce depression or low libido, and innumerable things can go right to alleviate such problems. If the brain were as simple as Wolf presents it, it just wouldn’t work. It’s not as straightforward as one neurotransmitter, one effect. “Science, particularly physiology, never works that way,” says Kathryn Clancy, assistant professor of anthropology at the University of Illinois, who studies reproductive behavior and blogs about “ladybusiness” for Scientific American, noting that, for example, two women with the exact same levels of hormones can have vastly different physiology — either a “lush, thick” uterine lining, say, or a very thin one. (MORE: What a Workout! Women Report that Exercise Triggers Orgasm) Wolf includes a similar oversimplification in her discussion of the neurotransmitter and hormone oxytocin, which is best known for its involvement in facilitating bonding between lovers and between parents and children. Wolf calls oxytocin “women’s emotional superpower” and, citing research in prairie voles, concludes that it makes women more likely to become emotionally connected with their sexual partners than men are. But Young says there’s no data on gender differences in oxytocin in humans. “Based on what we know from animals, it is likely that when women have sex that they are going to experience more of an oxytocin release than men,” he says, adding, “We don’t know.” Wolf then jumps from this conjecture to the notion that women’s intense oxytocin release makes them more likely to become literally addicted to sex: “Good sex is, in other words, actually addictive for women biochemically in certain ways that are different from the experience of men — meaning that one experiences discomfort when this stimulus is removed and a craving to secure it again.” From this unscientific claim, the author leaps even further afield, concluding that because of their biochemistry, women are less capable of controlling themselves when it comes to love and therefore, less human. “The tricky part, if you look at the new science, is that women are indeed, in sex, in some ways more like animals than men,” she writes. Note here that we’ve gone from assuming that an animal finding applies to humans to an assumption (one without any data at all) that the previous conclusion creates an uncontrollable desire for sex in women that is similar to addiction, which characterizes women in love as having little more self-control than animals. There is a truth buried among this nonsense, but it’s not the truth that Wolf is claiming. Love — for both men and women — relies on the same circuitry that engenders addiction. It’s the same circuitry that fuels the desire to persist in frustrating tasks like parenting as well. Like addiction, both love and parenting involve continuing with behavior despite negative consequences. But that’s a good thing: we need to be a little bit irrational to stay with partners who are far from perfect and to deal with children who can easily drive adults mad. (MORE: How a Squirt of Oxytocin Can Ease Marital Spats and Boost Social Sensitivity) This doesn’t mean, however, that we become powerless in the face of our brain chemistry. Even heroin addicts remain human and capable of self-control: you don’t see junkies shooting up in front of the police, for example. Similarly, people maintain control despite the pulls of parenting and love — and women aren’t any more romantically compulsive than men. That’s because the brain circuitry that drives us to love and parent — the same region that can be derailed during addiction — isn’t the only part of our brain. Even in the throes of addiction, romantic obsession or the early chaotic days of parenting, we’re still capable of choice, and none of the neuroscience data proves otherwise. “Just because genes or a molecule modulate a behavior, it doesn’t mean that genes or molecules determine that behavior,” says Young. “People who are in love will generally engage in behavior that they wouldn’t normally do, but I don’t think that means they’re less responsible.” Oddly, one of the few places in her book where Wolf gets the science right — in a discussion about the physiology of a clitoral vs. vaginal orgasm — quashes the universalizing claims she makes elsewhere in the book. It was a pinched pelvic nerve in Wolf’s spine that apparently prevented her from experiencing vaginal orgasms and a surgical cure of the problem that inspired the book. She notes that her doctor told her, “Every woman is wired differently; some women’s nerves branch more in the clitoris. Some branch a great deal in the perineum, or at the mouth of the cervix. That accounts for some of the differences in female sexual response.” Indeed, there is important new research suggesting that, for example, the wiring of these nerves affects the types of orgasms women have. Clitoral-focused orgasms seem to rely on one arm of the pudendal nerve, while cervical and some vaginal sensation and related orgasms are linked to the pelvic nerve. As Wolf rightly notes, this knowledge should bring comfort to women who think themselves different or psychologically immature for having the “wrong” kind of orgasm. Again, however, there is more complexity to the female orgasm than the author conveys. For one, as she mentions, new anatomical data suggests that the clitoris, far from being located only outside the body, actually wraps around the vagina internally. Which means that it too can be stimulated from within. “It’s shaped like a wishbone, and the tip of the wishbone is the part that is external,” says Barry Komisaruk, professor of psychology at Rutgers and a leading researcher on sexuality. “The rest of it has these two legs that straddle the vagina and during intercourse the penis can actually stretch the vagina to the point where the legs of clitoris are stimulated.” While there are distinct vaginal and clitoral orgasms experienced by many women, the two types of stimulation can also intermingle. Neither is inherently superior, nor required for conception. (MORE: Sharing a Bed Makes Couples Healthier) Moreover, Komisaruk and his colleagues have found that women with spinal injury, even those who have paralyzing damage, can often still have vaginal orgasms because the spine and pelvic nerve are not the only conductors of sensation from the vagina and cervix. The vagus nerve transmits these impulses too, outside of the spinal cord. “It’s probably that nerve that carries sensation in [women with] spinal-cord injuries [during orgasm],” says Komisaruk. Wolf’s vagus may not have functioned this way, but that doesn’t mean other women have the same problem. The brain and female sexuality are extremely complicated — and reducing them to simplistic formulations that deny women their humanity fails to do justice to either feminism or science. Properly contextualized, neuroscience can add to our knowledge of sexuality, but not if it’s twisted to support sexist ideas about women as “animals” who are so addicted to love that they become zombies. Maia Szalavitz is a health writer for TIME.com. All is belonged to Time Magazine.

Why Women Outlive Men

Researchers have discovered several mutations in the mitochondrial DNA of Drosophila that affect male lifespan and rate of aging, but have no effect on aging in females, according to a study published this week (August 2) in Current Biology. According to BBC News, there are about 50 percent more women in the UK population by the age of 85, and twice as many more women by the age of 100. And this pattern is not just limited to humans. Analyzing the mitochondria of male and female Drosophila melanogaster, Damian Dowling of Monash University in Australia and colleagues found that the mitochondria harbor numerous mutations that affect male, but not female, aging. Because mitochondria are passed down from the mother, evolutionary theory predicts that male-harming mutations can accumulate in its DNA. “If a mitochondrial mutation occurs that harms fathers, but has no effect on mothers, this mutation will slip through the gaze of natural selection, unnoticed,” Dowling told the BBC. “Over thousands of generations, many such mutations have accumulated that harm only males, while leaving females unscathed.” Of course, there are likely other factors at play as well, such as lifestyle, social and behavioral traits, and of course, hormones, ageing expert Tom Kirkwood of Newcastle University added. “It may be it does tell us something rather important about mitochondria and the difference between male and female fruit flies,” he told the BBC. “But I certainly don’t think this is a discovery that explains why women live 5–6 years longer than men." From The Scientist.

Brain imaging can predict how intelligent you are: 'Global brain connectivity' explains 10 percent of variance in individual intelligence

Brain imaging can predict how intelligent you are: 'Global brain connectivity' explains 10 percent of variance in individual intelligence

پیش‌بینی تلسکوپ هابل از زمان ادغام کهکشان راه شیری

منجمان با استفاده از تلسکوپ فضایی هابل، زمان ادغام کهکشان راه شیری و کهکشان آندرومدا را پیش‌بینی کرده‌اند قوه جاذبه این دو کهکشان، آنها را به سوی هم می‌کشد. تا چهار میلیارد سال دیگر ادغام آنها شروع می شود فرایند ادغام دو میلیارد سال طول می کشد.منجمان پیش بینی می کنند که به دلیل فاصله زیاد ستاره‌ها از هم، آنها با یکدیگر برخورد نمی کنند

.دارویی برای جلوگیری از ابتلا به ایدز A medicine for preventing of Aids

A new medicine for Aids or HIV is Truvada.It is just for prevention of the Aids not more.There is 2 problems for it 1-it is still expensive 2-You may think that with using of it there is no need to use of condom or truvada and there is no danger around you !.So Truvada is a drug that it is anti Retro viruses and today it is given to Aids patients for treatment.FDA would decide in future that give it to all people or not.

.توضیح در مورد نتایج یک تحقیق پیرامون نژاد ایرانیان

اینجانب در مصاحبه خود با گزارشگر محترم بی بی سی فارسی به هیچ عنوان ادعا و عنوان نکرده ام که "اکثر ایرانیان نژاد آریائی ندارند" و این جمله که به اشتباه به عنوان تیتر گزارش انتخاب شده، کاملا با آنچه اینجانب مطرح کرده و باور دارم متفاوت است تحقیقات اخیر ژنتیکی اینجانب نشان می دهند که عموم اقوام و گروه های جمعیتی ایرانی که در ایران امروزی (و حتی فراتر از مرزهای سیاسی فعلی ایران) ساکن هستند، علیرغم اینکه دارای تفاوتهای جزئی فرهنگی هستند و حتی گاه به زبانهای مختلف هم تکلم می کنند، دارای ریشه ژنتیکی مشترکی هستند و این ریشه مشترک به جمعیتی اولیه که در حدود ده تا یازده هزار سال پیش در قسمتهای جنوب غربی فلات ایران ساکن بوده بر می گردد. این مطالعات ژنتیک نشان می دهند که شباهت های ژنتیکی ما ایرانیان با اروپائیان نه به دلیل مهاجرت اقوامی از اروپا به ایران (در حدود چهار هزار سال قبل) بلکه به دلیل مهاجرت کشاورزان ایرانی به سمت اروپا (در حدود ده هزار سال قبل) می باشد. اندکی تفحص در منابع و مدارک تاریخی موجود نشان می دهد که کلمات "آریا و آریائی" به کرات توسط شخصیتهای تاریخی و مورخان داخلی و خارجی مورد استفاده قرار گرفته و دارای معانی مختلفی بوده اند، مثلا به عنوان نامی برای یک جمعیت باستانی در ایران، نامی برای زبان ایران باستان و حتی نامی برای سرزمینی که محل اقامت ایرانیان باستان بوده است به کار رفته است. اسناد و شواهد تاریخی و باستان شناسی نشان می دهد که آریائیان اقوامی مهاجر نبوده اند، بلکه از حدود ده هزار سال قبل در این سرزمین ساکن بوده و مبدا و منشاء بزرگترین ابداعات و نو آوریهای انسان مدرن بوده اند (از جمله ابداع کشاورزی، پیدایش نخستین روستاها و شهرهای کشف شده در جهان، اهلی کردن حیواناتی چون احشام برای اولین بار، ابداع خط و نگارش و بنیان گذاری بزرگترین و اولین تمدنهای پیشرفته بشری در بسیاری از نقاط ایران مانند جیرفت، سیلک، شهر سوخته). هر چند بررسی دقیق اینکه آریائیان که بوده اند، چه وقت و در کجای سرزمینهای ایران باستان ساکن بوده اند نیاز به تحقیقات جامع زبان شناسان، متخصصان تاریخ و باستان شناسی دارد، امروزه شواهد مختلفی از جمله یافته های باستان شناسی و ژنتیک درستی این فرضیه که اقوامی از سرزمینهای دور اروپائی به فلات ایران مهاجرت کرده اند را به طور جدی مورد سئوال قرار داده و آنرا رد می کنند. باور بنده اینست که برخی انسان شناسان و زبان شناسان اروپائی برای فرضیه نژادپرستانه خود که قصد توضیح و توجیه ریشه مشترک و نحوه گسترش زبانهای هندو-اروپائی و حتی برتری نژادی برخی اروپائیان را داشته است و برای اصالت بخشیدن به این فرضیه خود نیاز به یک نام اصیل و باستانی داشته اند و نام "آریائی" را که ریشه در زبانهای سانسکریت و ایران باستان دارد را به امانت گرفته و به نوعی مورد سوء استفاده قرار داده اند. همزمانی این سوء استفاده علمی دانشمندان اروپائی در قرون نوزدهم و بیستم میلادی با سیاستهای ملی گرایانه وقت و تبلیغات وسیع و آموزش اینکه ایرانیان ریشه در جمعیتهای (آریائی) اروپائی دارند، در طول چندین دهه این باور غلط را در ذهن ما ایرانیان ایجاد کرده است که در حدود چهار هزار سال قبل قبایلی که به زبانهای هندو-اروپائی صحبت می کرده اند (و دانشمندان اروپائی آنها را آریائی نام نهاده اند)، از شمال وارد فلات ایران شده و جایگزین اقوام بومی ایران شده اند و ما ایرانیان امروزی از اعقاب این آریائیان مهاجر هستیم. استناد این دانشمندان اروپائی تغییر زبان ایرانیان باستان از دراویدی به هندو-اروپائی در حدود چهار هزار سال پیش است. تحقیقات بسیار جدید و برجسته ژنتیکی و زبان شناسی نشان می دهند که زبان یک جمعیت براحتی و حتی با حضور فقط ده در صد از مردان مهاجم یا مهاجر که مزیت و برتری نسبی نسبت به جمعیت بومی داشته اند تغییر می کرده است. این مسئله در کنار شواهد مربوط به تغییرات عمده آب و هوائی و خشکسالی بسیار شدید در فلات ایران که منجر به محو تمدنهای جنوب و جنوب شرقی ایران و مهاجرت وسیع ایرانیان به سمت شمال (در حدود چهار هزارو دویست سال قبل) شده اند، می توانند براحتی تغییر زبان رایج در ایران (از زبان دراویدی به هندو-اروپائی) را در حدود چهار هزار سال قبل توجیه کنند. در پایان و بطور خلاصه اعتقاد بنده اینست که عموم ما ایرانیان از اعقاب آریائیهائی هستیم که از بیش از ده هزار سال قبل در این سرزمین می زیسته اند و بزرگترین تمدنهای انسانی را پایه گذاری کرده اند و تئوری مهاجرت اقوامی از اروپای شرقی به ایران (که به غلط و حتی عمدا توسط عده ای از دانشمندان اروپائی نام آریائی بر آنها نهاده شده) و جایگزینی اقوام بومی توسط آنان یک فرضیه غلط و نژاد پرستانه وارداتی است. دکتر مازیار اشرفیان بناب دانشگاه پورتموث - انگلستان

.ابداع تازه جراحان ایرانی در آلمان برای جراحی عروق

چند جراح ايرانی در بيمارستان دانشگاه هانوفر آلمان به یک روش جديد جراحی عروق رسیده اند. با این پیشرفت پزشکی دیگر لازم نیست اعضای بدن بیماران دیابتی را قطع کرددکتر فرخ رحیمی و دکتر امیر حسین عظیمی ابداع کنندگان این روش جراحان بیماری های عروق هستند

رابطه مصرف گوشت فرآوری شده با سرطان لوز المعده

محققان در سوئد می گویند که مصرف گوشت فرآوری شده مثل سوسیس و کالباس می تواند با سرطان لوز المعده رابطه مستقیمی داشته باشد.این محققان می گویند که مصرف پنجاه گرم گوشت فراوری شده اضافه تر در روز (معادل یک سوسیس) می تواند خطر ابتلا به سرطان لوزالمعده را ۱۹ در صد افزایش دهد.با این حال سرطان لوزالمعده نسبت به برخی دیگر از سرطانها بسیار نادرتر است .صندوق جهانی تحقیقات سرطان می گوید که رابطه مستقیم میان مصرف گوشت فرآوری شده با سرطان لوز المعده می تواند در افراد "چاق مفرط" پدیدار شود.توصیه صندوق جهانی تحقیقات سرطان این است که مردم اصولا از مصرف گوشتهای فرآوری شده مثل سوسیس و کالباس کلا خودداری کننددکتر ریچل تامپسون، معاون علمی صندوق جهانی تحقیقات سرطان، می گوید که این صندوق همچنین توصیه می کند که مصرف گوشت قرمز پخته شده نیز از ۵۰۰ گرم (نیم کیلو) در هفته تجاوز نکندسوزانا لارسون، استاد و محقق موسسه کارولینسکا سوئد، می گوید که رابطه مصرف گوشت و سرطانهای روده بزرگ از قبل مشخص بوده است، آنچه که دانشمندان کمتر نسبت به آن آگاهی دارند چگونگی رابطه مصرف گوشتهای فراوری شده با دیگر سرطانها است .نتیجه تحقیقات انجام شده در موسسه کارولینسکا سوئد، در مجله علمی موسوم به نشریه بریتانیایی سرطان (British Journal of Cancer) منتشر شده و حاوی نتایج یازده مطالعه عملی و ۶۶۴۳ بیمار دارای سرطان لوزالمعده بوده است
ماخذ:بی بی سی

Strict diet could save brain from aging

WASHINGTON
Eating less may keep the mind young, according to Italian scientists who say they have discovered the molecular process by which a strict diet may save the brain from the ravages of age.

The research, published in the U.S. journal the Proceedings of the National Academy of Sciences, is based on a study of mice that were fed a diet of about 70% of the food they normally consumed.

Scientists found the calorie-restricted diet triggered a protein molecule, CREB1, that activates a host of genes linked to longevity and good brain function.

“Our hope is to find a way to activate CREB1, for example through new drugs, so to keep the brain young without the need of a strict diet,” said lead author Giovambattista Pani, researcher at the Institute of General Pathology, Faculty of Medicine at the Catholic University of Sacred Heart in Rome.

Researchers have previously discovered that mice on diets showed better cognitive abilities and memory, less aggression, and tended to avoid or delay Alzheimer’s disease. But they have not known exactly why.

“CREB1 is known to regulate important brain functions as memory, learning and anxiety control, and its activity is reduced or physiologically compromised by aging,” said the study.

Mice that were genetically altered to lack CREB1 showed none of the same memory benefits if they were on a low-calorie diet as mice that had the molecule, and showed the same brain disabilities as mice that were overfed.

“Thus, our findings identify for the first time an important mediator of the effects of diet on the brain,” Pani said.

“This discovery has important implications to develop future therapies to keep our brain young and prevent brain degeneration and the aging process.”

According to Marc Gordon, chief of neurology at Zucker Hillside Hospital in Glen Oaks, New York, the findings could shed new light on why some people who are obese in middle age encounter cognitive problems later in life.

“Mid-life obesity has been associated with late-life dementia. However, the physiological basis for this association remains unclear,” said Gordon, who was not part of the study.

“These investigators have studied the effects of limiting caloric intake in mice, and have identified a biochemical pathway that may mediate at least some of the brain’s responses to dietary restriction.”

Refrence:Japan Today