Chapter 5. Hormones and the Brain
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By Lauren Gravitz, Connor was diagnosed with autism early — when he was just 18 months old. His condition was already obvious by then. “He was lining things up, switching lights on and off, on and off,” says his mother, Melissa. He was bright, but he didn’t speak much until age 3, and he was easily frustrated. Once he started school, he couldn’t sit still in class, called out answers without raising his hand and got visibly upset when he couldn’t master a math concept or a handwriting task quickly enough. “One time, he rolled himself up into the carpet like a burrito and wouldn’t come out until I got there,” Melissa recalls. (All families in this story are identified by first name only, to protect their privacy.) Connor was prescribed his first psychiatric drug, methylphenidate (Ritalin), at age 6. That didn’t last long, but when he was 7, his parents tried again. A psychiatrist suggested a low dose of amphetamine and dextroamphetamine (Adderall), a stimulant commonly used to treat attention deficit hyperactivity disorder (ADHD). The drug seemed to improve his time at school: He was able to sit still for longer periods of time and focus on what his teachers were saying. His chicken-scratch handwriting became legible. Then, it became neat. Then perfect. And then it became something Connor began to obsess over. “We were told that these are the gives and takes; if it’s helping him enough to get through school, you have to decide if it’s worth it,” Melissa says. It was worth it — for a while. © 2017 Scientific American
Link ID: 23531 - Posted: 04.25.2017
Paula Span “During the past four weeks, have you been tired? Been exhausted? Had difficulty getting motivated to do anything at all?” These questions — which a substantial chunk of the population probably could answer in the affirmative — appeared on a questionnaire used in a major European study published recently in The New England Journal of Medicine. The authors were researching the effectiveness of a drug that is widely, if controversially, used to treat older adults with subclinical hypothyroidism, better known as a slightly underactive thyroid. So many Americans take that medication — levothyroxine (brand name Synthroid) — that it topped the list of prescription drugs dispensed in the United States in 2015, according to the research firm QuintilesIMS Institute. With 121 million prescriptions annually, levothyroxine outpaced statins, blood pressure meds — and everything else. A Johns Hopkins survey published last year found that more than 15 percent of older Americans were taking it. So you’d think these study results would come as shocking news: The European team reported that in older people with mild hypothyroidism, the drug had no significant effect on symptoms. At all. Instead, the results bolstered what a number of geriatricians and endocrinologists have suspected for years. “It’s a strong signal that this is an overused medication,” said Dr. Juan Brito, an endocrinologist at the Mayo Clinic. “Some people really need this medicine, but not the vast majority of people who are taking it.” © 2017 The New York Times Company
Keyword: Hormones & Behavior
Link ID: 23522 - Posted: 04.22.2017
Carl Zimmer The oldfield mouse doesn’t seem extraordinary. With soulful black eyes and tiny teacup ears, the rodent lives a humdrum life scurrying about meadows and beaches in the Southeast. But field biologists have long known that when it comes to sex and family life, this mouse is remarkable: Peromyscus polionotus is monogamous — an exception among mammals — and a solicitous parent. Fathers and mothers will dig burrows together and build elaborate nests when pups are on the way; after they’re born, the father will help tend to the pups, retrieving them when they fall out of the nest, licking them, and huddling to keep them warm. In a pioneering study published on Wednesday in the journal Nature, researchers at Harvard University identified a genetic basis for this distinctive behavior. It is the first time that scientists have linked DNA to variations in parenting habits among mammals. Dieter Lukas, an evolutionary biologist at the University of Cambridge who was not involved in the research, hailed the study as a sophisticated tour de force, saying that uncovering these links “is like designing a tool to follow individual threads through a large colorful tapestry.” The findings may one day help scientists make sense of how human couples bond and care for their children. Mammals share many of the genes governing the production of hormones and neurotransmitters in the brain. Variations in how they function may explain why most species are promiscuous, why a few are monogamous — and why some, like humans, are somewhere in between. “We can go from the bottom up and build our knowledge base, and then ask questions about human biology,” said Gene E. Robinson, a biologist at the University of Illinois who was not involved in the new work. © 2017 The New York Times Company
Laura Sanders Soon after systems biologist Juergen Hahn published a paper describing a way to predict whether a child has autism from a blood sample, the notes from parents began arriving. “I have a bunch of parents writing me now who want to test their kids,” says Hahn, of Rensselaer Polytechnic Institute in Troy, N.Y. “I can’t do that.” That’s because despite their promise, his group’s results, reported March 16 in PLOS Computational Biology, are preliminary — nowhere close to a debut in a clinical setting. The test will need to be confirmed and repeated in different children before it can be used to help diagnose autism. Still, the work of Hahn and colleagues, along with other recent papers, illustrates how the hunt for a concrete biological signature of autism, a biomarker, is gaining speed. Currently, pediatricians, child psychologists and therapists rely on behavioral observations and questionnaires, measures with limitations. Barring genetic tests for a handful of rare mutations, there are no blood draws, brain scans or other biological tests that can reveal whether a child has — or will get — autism. Objective tests would be incredibly useful, helping provide an early diagnosis that could lead to therapy in the first year of life, when the brain is the most malleable. A reliable biomarker might also help distinguish various types of autism, divisions that could reveal who would benefit from certain therapies. And some biomarkers may reveal a deeper understanding of how the brain normally develops. |© Society for Science & the Public 2000 - 2017
By JENNIFER MALIA In “Meet Julia,” an episode of “Sesame Street” that will air April 10 on PBS and HBO, Elmo and Abby Cadabby introduce Big Bird to Julia, a new muppet character with autism. Big Bird says, “Hi, Julia, I’m Big Bird. Nice to meet you.” But Julia continues painting without making eye contact or responding to Big Bird. On “60 Minutes,” Big Bird tells Lesley Stahl, who was on the set when “Sesame Street” was filming the new Muppet’s debut, that he thought Julia didn’t like him at first. Elmo then explains, “Julia has autism so sometimes it takes her a little longer to do things.” I can relate. When my daughter started preschool, she would run laps around the perimeter of the fenced-in playground without responding to kids who said “hi” as she passed by. One day, she stopped in her tracks to pick up a jacket that had fallen to the ground, handed it to a girl without saying a word, and continued running. The kids on the playground probably assumed she didn’t like them — just as Big Bird did. Within the past year, my daughter, who is now 3, my 2-year-old son and I were all given diagnoses of autism spectrum disorder because of our repetitive behaviors, obsessive interests, sensory issues and difficulty with social interactions and pragmatic communication skills. My kids are on the mild to moderate part of the spectrum, having language, but not intellectual, impairments. (I also have a 4-year-old daughter who does not have a diagnosis.) Julia gives me hope that my children and their peers will grow up in a world where autism is normalized, rather than stigmatized. Preschoolers are the primary audience for “Sesame Street,” an educational television program where young children watching Julia’s interactions with her peers can learn by example to support autism acceptance. Since one in 68 American children have an autism diagnosis, wider understanding of the condition is valuable for them as well as for their peers. © 2017 The New York Times Company
Link ID: 23462 - Posted: 04.07.2017
By RONI CARYN RABIN Television ads for “low T” have sparked a rise in the use of testosterone gels, patches and injections by older men in recent years, according to a new report. But anyone hoping that a dose of testosterone will provide an easy antidote for sagging muscles, flagging energy and a retiring sex drive may find the results of recent government studies of the sex hormone sobering. The latest clinical trials, published over the past year, are the first rigorous ones to assess the potential beneficial effects of testosterone treatment for older men with abnormally low levels of the hormone. Scientists followed 790 men age 65 and older who had blood testosterone levels below 275 nanograms per deciliter of blood, well below the average for healthy young men and lower than would be expected with normal aging. The men also had symptoms reflecting their low hormone levels, like loss of sex drive. Half the participants were treated with testosterone gel, and half were given a placebo gel. The studies reported mixed results, finding that over the yearlong study period, testosterone therapy corrected anemia, or low levels of red blood cells, which can cause fatigue, and increased bone density. But a study to see if testosterone improved memory or cognitive function found no effects. Meanwhile, a red flag warning of possible risks to the heart emerged from the studies: Imaging tests found a greater buildup of noncalcified plaque in the coronary arteries of men treated with testosterone for a year, an indicator of cardiac risk, compared with those who were given a placebo gel. The findings of plaque were not a complete surprise; many reports have tied testosterone use to an increase in heart attacks, and the Food and Drug Administration already requires testosterone products to carry warnings of an increased risk of heart attacks and stroke (men at high risk of cardiovascular disease were not allowed to participate in the latest trials). But observational studies, which are weaker, have yielded mixed results over all, with one study published last month finding that men taking testosterone actually had fewer heart problems. © 2017 The New York Times Company
By Daisy Yuhas, Spectrum on March 22, 2017 In children with a deletion on chromosome 22, having autism does not boost the risk of developing schizophrenia later in life, according to a new study1. The children in the study have 22q11.2 deletion syndrome, which is linked to a 25-fold increase in the risk of developing a psychotic condition such as schizophrenia. A deletion in the region is also associated with an increased risk of autism. Some researchers have suggested that the relatively high autism prevalence in this population is the result of misdiagnoses of early signs of schizophrenia. The new findings, published 21 January in Schizophrenia Research, support an alternate theory: Autism and schizophrenia are independent outcomes of the same genetic syndrome. If there is a relationship between the two conditions, “that can only be a very small, probably negligible effect,” says lead investigator Jacob Vorstman, assistant professor of child psychiatry and genetics at the University Medical Center Utrecht in the Netherlands. The new findings could help guide clinical care, says Opal Ousley, assistant professor of psychiatry at the Emory Autism Center in Atlanta. If prenatal testing picks up the 22q11.2 deletion, for instance, clinicians could discuss the risk of both autism and schizophrenia with parents. © 2017 Scientific American
By Jill Serjeant NEW YORK (Reuters) - Long-running children's television show "Sesame Street" is welcoming a new kid to the block - a Muppet with autism called Julia. A redhead who loves to sing and remembers the words to lots of songs, Julia will debut on the show for preschoolers on April 10 after a five-year outreach effort to families and experts on autism, Sesame Workshop said on Monday. "For years, families of children with autism have asked us to address the issue," Dr. Jeanette Betancourt, senior vice president of U.S. social impact at the nonprofit Sesame Workshop, said in a statement. One in 68 American children is currently diagnosed with autism, according to the Centers for Disease Control and Prevention, an increase of some 119 percent since 2000. Autism is a developmental disorder present from early childhood, characterized by difficulty in communicating and forming relationships with other people and in using language and abstract concepts Stacey Gordon, the puppeteer who will perform the role of Julia, and Christine Ferraro who wrote her part, both have family members who are on the autism spectrum. "It's important for kids without autism to see what autism can look like," Gordon told the CBS show "60 Minutes" in a preview on Sunday. "Had my son's friends been exposed to his behaviors through something that they had seen on TV before they experienced them in the classroom, they might not have been frightened. They might not have been worried when he cried. They would have known that he plays in a different way and that that's okay," she added. © 2017 Scientific American
Link ID: 23387 - Posted: 03.22.2017
By Abby Olena Researchers have shown that a hormone secreted by bone, called lipocalin 2 (LCN2), suppresses appetite in mice. The results, published today (March 8) in Nature, suggest that LCN2 crosses the rodents’ blood-brain barrier and binds a receptor in the hypothalamus. The team also found a link between body weight and LCN2 levels in people with type 2 diabetes. The authors “have identified a protein that’s secreted from bone that has a pretty significant impact on feeding behavior,” Lora Heisler of the University of Aberdeen in Scotland, who did not participate in the work, told The Scientist. “And the fact that they found that some supporting evidence in humans is really exciting.” “We have found a new role for bone as an endocrine organ, and that is its ability to regulate appetite,” said study coauthor Stavroula Kousteni of Columbia University in New York City. Scientists had previously identified LCN2 as a protein expressed in fat cells, but Kousteni and colleagues showed that it is enriched 10-fold in osteoblasts. When they generated mice without LCN2 in their osteoblasts, levels of the circulating hormone dropped 67 percent. These mice ate more than control animals and showed increases in fat mass and body weight. When the authors injected LCN2 into wild-type or obese mice, the rodents ate less food. The treated animals showed decreases in body weight, fat mass, and weight gain. LCN2 injections also led to increases in insulin levels and glucose tolerance, the scientists showed. © 1986-2017 The Scientist
By Bahar Gholipour, Spectrum An analysis of whole-genome sequences from more than 5,000 people has unearthed 18 new candidate genes for autism. The study, the largest yet of its kind, was published this week in Nature Neuroscience. The new work identified 61 genes associated with autism, 43 of which turned up in previous studies. An independent study published last month looked at several autism genes and made a strong case for three of the new genes2. Most of the new candidates play roles in cellular processes already implicated in autism and intellectual disability. They also point to possible new treatments. “Eighty percent of them involve common biological pathways that have potential targets for future medicines,” says study investigator Ryan Yuen, research associate at the Hospital for Sick Children in Toronto, Canada. The study is the largest analysis of whole genomes from people with autism and their family members to date. Participants are enrolled in MSSNG, an effort funded by Google and the nonprofit group Autism Speaks to analyze sequences from 10,000 people. Other studies typically focus on the coding regions of the genome, called theexomes. Most of the mutations identified in the new work land in genes, but some affect noncoding regions of the genome. Understanding the role of these noncoding mutations is a “challenging task,” says Ivan Iossifov, associate professor at Cold Spring Harbor Laboratory in New York, who was not involved in the study. “The more data that’s available, the better,” he says. “This paper provides a very useful resource for the community to further study.” © 2017 Scientific American,
Nicola Davis The mystery of why sheep get horny in the winter might have been solved, according to new research. Scientists say they have uncovered the key to the mechanism by which changes in the length of the day prompt certain animals to begin breeding, trigger the growth of horns and even change the thickness of their coat. The findings, the team add, could help farmers tinker with the timing of the lambing season. “Now we know what that link is we can start to understand how it can be controlled,” said David Bates, professor of oncology at the University of Nottingham and co-author of the research. It has long been known that changes in animals’ fertility over the seasons is linked to melatonin – a hormone released at night from the pineal gland in the brain. This hormone acts on another gland, the pituitary, affecting the levels of various sex hormones it produces. With the onset of fertility in sheep linked to longer periods of melatonin production, winter is the season for ovine Casanovas. But there is a puzzle. The region of the pituitary gland that detects melatonin is separate to the region that produces sex hormones. As a result, scientists had been baffled as to how melatonin ends up affecting the onset of fertility. “No-one has been able to find what the link is,” said Bates. Now Bates and colleagues from the University of Bristol say they have the answer. Writing in the journal PNAS, the team reveal the missing link is a protein, known as vascular endothelial growth factor, which is made in the region of the pituitary gland that detects melatonin. © 2017 Guardian News and Media Limited
By Jessica Wright, Spectrum The prevalence of autism in the United States has risen steadily since researchers first began tracking it in 2000. The rise in the rate has sparked fears of an autism ‘epidemic.’ But experts say the bulk of the increase stems from a growing awareness of autism and changes to the condition’s diagnostic criteria. Here’s how researchers track autism’s prevalence and explain its apparent rise. How do clinicians diagnose autism? There is no blood test, brain scan or any other objective test that can diagnose autism—although researchers are actively trying to develop such tests. Clinicians rely on observations of a person’s behavior to diagnose the condition. In the U.S., the criteria for diagnosing autism are laid out in the “Diagnostic and Statistical Manual of Mental Disorders” (DSM). The criteria are problems with social communication and interactions, and restricted interests or repetitive behaviors. Both of these ‘core’ features must be present in early development. What is the prevalence of autism in the U.S.? The Centers for Disease Control and Prevention (CDC) estimates that 1 in 68children in the U.S. have autism. The prevalence is 1 in 42 for boys and 1 in 189 for girls. These rates yield a gender ratio of about five boys for every girl. © 2017 Scientific American,
Link ID: 23305 - Posted: 03.03.2017
By Melissa Pandika Groundbreaking research suggests that a treatment for autism may come in the form of a probiotic. Stress can send your stomach into a painful tailspin, causing cramps, spasms and grumbling. But trouble in the gut can also affect the brain. This two-way relationship may be an unlikely key to solving one of medicine’s most pressing — and perplexing — mysteries: autism. Nearly 60 years after the disorder was first identified, the number of cases has surged, and the United Nations estimates that up to 70 million people worldwide fall on the autism spectrum. Yet there is no known cause or cure. But scientists have found promising clues in the gut. Research has revealed striking differences in the trillions of bacteria — a.k.a., the microbiome — in the intestines of children with and without autism. But the gut bacteria in individuals with autism aren’t just different. Researchers at the California Institute of Technology have shown for the first time that they may actually contribute to the disorder. They reported in the journal Cell in December 2013 that an experimental probiotic therapy alleviated autism-like behaviors in mice and are already planning a clinical trial. Today autism is treated primarily through behavioral therapy. But the new study suggests that treatment may one day come in the form of a probiotic — live, beneficial bacteria like those found in yogurt. “If you block the gastrointestinal problem, you can treat the behavioral symptoms,” Paul Patterson, a professor of biology at Caltech who co-authored the study told SFARI.org. University of Colorado Boulder professor Rob Knight hailed the finding as “groundbreaking” in a commentary in Cell. © OZY 2017 Terms & Conditions
By Claudia Wallis Dinosaurs, Star Wars, train schedules, Disney princesses, maps, LEGO—subjects such as these can become all-consuming passions for children on the autism spectrum. What therapists and educators often call “circumscribed” or “restricted” interests (or, more generously, “special” interests) make up a characteristic symptom of autism spectrum disorder (ASD). The current edition of psychiatry’s Diagnostic and Statistical Manual of Mental Disorders describes them as “highly restricted, fixated interests that are abnormal in intensity or focus.” Roughly 90 percent of high-functioning kids with ASD display at least one such interest during their elementary school years, according to a 2007 survey conducted at the Yale University Child Study Center, one of the few studies to have examined the topic. For a family with an affected child, this kind of narrow preoccupation can be tedious and exhausting. Imagine a kid who will talk about nothing but the exits on the New Jersey Turnpike or the Captain Underpants book series. (Both actual examples.) Therapists and educators have traditionally tried to suppress or modulate a child’s special interest, or use it as a tool for behavior modification: Keep your hands still and stop flapping, and you will get to watch a Star Wars clip; complete your homework or no Harry Potter. But what if these obsessions themselves can be turned into pathways to growth? What if these intellectual cul-de-sacs can open up worlds? That is the idea explored in the film Life, Animated, a contender for the Academy Award for Best Documentary this Sunday night. © 2017 Scientific American
Link ID: 23277 - Posted: 02.24.2017
Jon Brock What if I told you that we can now identify babies who are going to develop autism based on a simple brain scan? This, in essence, is the seductive pitch for a study published last week in the journal Nature, and making headlines around the world. Early identification and diagnosis is one of the major goals of autism research. By definition, people with autism have difficulties with social interaction and communication. But these skills take many years to develop, even in typically developing (i.e., non-autistic) children. Potential early signs of autism are extremely difficult to pick out amidst the natural variation in behaviour and temperament that exists between all babies. A brain scan for autism would be a major step forward. But is the hype justified? Are we really on the brink of a new era in autism diagnostics? Without wishing to detract from the efforts of everyone involved in the study, it’s important to look at the results critically, both in terms of the scientific findings and their potential implications for clinical practice. The study, led by Heather Cody Hazlett at the University of North Carolina, was part of a larger research program investigating the development of babies who have an older sibling with autism. Because autism runs in families, these babies are much more likely to develop autism than babies from the general population.
Patricia Neighmond Many men over 65 with low testosterone levels say their sense of well-being, not to mention sexual function, isn't what it used to be. That's why some doctors prescribe testosterone replacement. But the effectiveness of testosterone has been controversial. Studies of the risks and benefits have been mixed, and the Food and Drug Administration beefed up its warnings about cardiac side effects of testosterone supplementation in 2015. And the findings of five studies released Tuesday aren't likely to clear up the confusion. They appear in JAMA, the journal of the American Medical Association and JAMA Internal Medicine. The studies are collectively called the Testosterone Trials (TTrials) and they compared a testosterone gel, AndroGel, against a placebo. The results are based on 788 men with below normal levels of testosterone studied at 12 sites across the country over a year. Overall, researchers saw improvements in bone density and bone strength in men who used a testosterone gel, which raised their testosterone to levels seen in younger men. In men with unexplained anemia, testosterone also improved iron levels in the blood. (A reviewer of the study raised questions about whether it was done ethically.) But in men using testosterone who had been reporting memory problems at the start of the study, there were no improvements in memory or cognition. And there were worrisome signs of an increase in the risk of cardiovascular problems. © 2017 npr
Ewen Callaway Researchers have no way to tell whether young babies may later be diagnosed with autism. But brain scans could help, a small study suggests. By scanning the brains of babies whose siblings have autism, researchers say they have been able to make reasonably accurate forecasts about which of these high-risk infants will later develop autism themselves. The findings raise the prospect of diagnosing autism spectrum disorder (ASD) months before children develop symptoms, a goal that has proved elusive. Nature looks at the new study and its implications. Why has it been so tough to diagnose autism in infants? Children typically show symptoms of ASD, such as difficulty making eye contact, after the age of 2. Researchers believe that the brain changes underlying ASD begin much earlier — possibly even in the womb. But behavioural assessments haven't been helpful in predicting who will get autism, says Joseph Piven, a psychiatrist at the University of North Carolina (UNC) in Chapel Hill, who co-led the study, published online in Nature1. “Children who end up with autism at 2 or 3, they don’t look like they have autism in the first year," he says. Certain rare mutations are linked to ASD, but the vast majority of cases cannot be pinned to a single or even a handful of genetic risk factors. Beginning in the 1990s, Piven and other researchers noticed that children with autism tended to have larger brains than developmentally normal children, suggesting that brain growth could be a biomarker for ASD. But Piven and colleague Heather Cody Hazlett, a psychologist at UNC-Chapel Hill, say it had not been clear when overgrowth occurred. What did their latest study look at? © 2017 Macmillan Publishers Limited,
By Jesse Singal Those who advocate for sound, evidence-based research about autism are extremely alarmed about Donald Trump, and for good reason: In addition to Trump’s ties to Andrew Wakefield, the disgraced British doctor whose debunked research helped fuel the false idea of links between childhood vaccines and autism, Robert F. Kennedy Jr., a notorious anti-vaxxer himself, told reporters back in January that Trump planned to tap him as chair of a commission on “vaccine safety.” There is no question at this point that Trump has significant connections to a pseudoscientific medical movement that spreads dangerous, disproven ideas. Today, Trump gave nervous observers yet more reason to worry. It occurred at a White House event in which Trump and Secretary of Education Betsy DeVos met with a bunch of educators. Trump seemed to fixate, for a moment, on one educator named Jane (her last name is hard to make out) after she explained that she is the principal of a special education center in Virginia. The sequence starts at about 5:38 in this video: After Jane noted that many of her students have autism, Trump asked, “Have you seen a big increase in the autism, with the children?” Jane replied in the affirmative, but seemed to couch her response as being more about an increase in demand for services — she didn’t explicitly agree there’s been a big increase in the overall rate. Trump continued: “So what’s going on with autism? When you look at the tremendous increase, it’s really — it’s such an incredible — it’s really a horrible thing to watch, the tremendous amount of increase. Do you have any idea? And you’re seeing it in the school?” Jane replied — again, in a way that seems a bit noncommittal vis-à-vis Trump’s claim — that the rate of autism is something like 1-in-66 or 1-in-68 children. To which Trump responds: “Well now, it’s gotta be even lower [presumably meaning higher, rate-wise] than that, which is just amazing — well, maybe we can do something.” (Jane had the rate right, and Trump is incorrect that it has crept higher.) © 2017, New York Media LLC.
Link ID: 23233 - Posted: 02.15.2017
Having a thicker outer layer of the brain is linked to an increased likelihood of having autism. The cerebral cortex is the wrinkled outer layer of the brain that is responsible for many of our most human traits, including thought, language and consciousness. This layer is typically thicker in men than in women, and its structure has been linked to differences in personality. Now brain scans have shown that women who have a more male-like brain structure are three times more likely to have been diagnosed with autism. The study compared the brains of 98 men and women with high functioning autism with those of 98 people who don’t have autism. These findings provide new insights into the brain’s role in sex differences in autism, according to the team that did the study. Autism is thought to be two to five times more common in men than in women, and some think the condition is caused by having an “extreme male brain”. Journal reference: JAMA Psychiatry, DOI: 10.1001/jamapsychiatry.2016.3990 © Copyright Reed Business Information Ltd.
In the mood? Feeling sexy and romantic has been linked to a hormone named kisspeptin. Researchers hope the chemical may help treat people with some sexual problems. Kisspeptin occurs naturally in the body, where it stimulates the release of other signalling chemicals that have been linked to reproduction. Now a study of 29 heterosexual young men has found that injections of the hormone enhance the brain’s response to sexual and romantic pictures of couples. After injection, MRI scans showed increased activity in the regions of the brain that are usually stimulated by sexual arousal and romance. But this activity was only prompted by arousing pictures – non-sexy images did not have the same effect. “Our findings indicate that kisspeptin could play a role in stimulating some of the emotions and responses that lead to sex and reproduction,” says Waljit Dhillo, at Imperial College London. “Ultimately, we are keen to look into whether kisspeptin could be an effective treatment for psychosexual disorders.” The team now plans to study the effects of the hormone in a larger group of people, including women as well as men. Journal reference: Journal of Clinical Investigation © Copyright Reed Business Information Ltd.