// by Jennifer Viegas Certain animals may weep out of sorrow, similar to human baby cries, say animal behavior experts. Many may have wondered if this was true after news reports last week described a newborn elephant calf at Shendiaoshan Wild Animal Nature Reserve in eastern China. The calf reportedly cried inconsolably for five hours after being stomped on by his mother that then rejected the little elephant. The calf, named Zhuang-zhuang, has since been "adopted" by a keeper and is doing well, according to the news site Metro. "Some mammals may cry due to loss of contact comfort," animal behaviorist Marc Bekoff explained to Discovery News. An ape's laugh is similar to a human one, according to new research exploring the evolution of laughter. "It could be a hard-wired response to not feeling touch," added Bekoff, former professor of ecology and evolutionary biology at the University of Colorado, Boulder. © 2013 Discovery Communications, LLC.

Keyword: Emotions; Evolution
Link ID: 18661 - Posted: 09.18.2013

By Sarah Amandolare Decades of research and billions of dollars go into developing and marketing drugs. Here's the life span of a typical brain drug—Cymbalta, a popular antidepressant Tuberculosis researchers discover that a drug that treats infections, called iproniazid, also boosts patients' mood. They learn that iproniazid slows the breakdown of three chemicals in the brain— serotonin, norepinephrine and dopamine. These molecules take center stage in the next two decades, as scientists search for antidepressants. 1974 Eli Lilly researchers develop fluoxetine (Prozac), the first selective serotonin reuptake inhibitor. Fluoxetine thwarts the absorption, or “reuptake,” of serotonin. This boosts levels of the chemical in the pockets of space between neurons. Prozac does not hit drugstore shelves until 1988. 1980s Scientists start tinkering with the reuptake of norepinephrine and dopamine, which, in addition to elevating mood, can relieve muscle and joint pain. They dub this new class of antidepressants serotonin-norepinephrine reuptake inhibitors (SNRIs). At Eli Lilly, scientists begin developing an SNRI with a special focus on norepinephrine. One of their molecules becomes known as duloxetine, later branded Cymbalta. 1986 © 2013 Scientific American

Keyword: Depression
Link ID: 18660 - Posted: 09.18.2013

By PAM BELLUCK It is a new frontier of the anti-abortion movement: laws banning abortion at 20 weeks after conception, contending that fetuses can feel pain then. Since 2010, a dozen states have enacted them, most recently Texas. Nationally, a bill passed the Republican-dominated House of Representatives in June. The science of fetal pain is highly complex. Most scientists who have expressed views on the issue have said they believe that if fetuses can feel pain, the neurological wiring is not in place until later, after the time when nearly all abortions occur. Several scientists have done research that abortion opponents say shows that fetuses can feel pain at 20 weeks after conception. One of those scientists said he believed fetuses could likely feel pain then, but he added that he believed the few abortions performed then could be done in ways to avoid pain. He and two other scientists said they did not think their work or current evidence provided scientific support for fetal-pain laws. Some scientists’ views have evolved as more research has been done. Dr. Nicholas Fisk, a senior maternal-fetal medicine specialist at Royal Brisbane and Women’s Hospital in Australia, said he once considered early fetal pain “a major possibility” after finding that fetuses receiving blood transfusions produced increased stress hormones and blood flow to the brain, and that painkillers lowered those levels. But Dr. Fisk, a former president of the International Fetal Medicine and Surgery Society, said neurological research has convinced him that pain “is not possible at all” before 24 weeks. © 2013 The New York Times Company

Keyword: Pain & Touch; Development of the Brain
Link ID: 18659 - Posted: 09.17.2013

Drugs to treat Alzheimer's disease don't help patients with mild cognitive impairment and are linked to greater risk of harm, a Canadian review concludes. People with mild cognitive impairment show symptoms of memory problems that are not severe enough to be considered dementia or to interfere with day-to-day functioning. Each year, three to 17 per cent of people with mild cognitive impairment deteriorate to dementia, research suggests. It was hoped that "cognitive enhancers" used to treat dementia might delay progression to dementia. Dr. Sharon Straus of the department of geriatric medicine at the University of Toronto and her team reviewed clinical trials and reports on the effects of four cognitive enhancers. "Cognitive enhancers did not improve cognition or function among patients with mild cognitive impairment and were associated with a greater risk of gastrointestinal harms," the reviewers concluded in Monday's issue of the Canadian Medical Association Journal. "Our findings do not support the use of cognitive enhancers for mild cognitive impairment." The medications act on different neurotransmitters in the brain, such as acetylcholine. © CBC 2013

Keyword: Alzheimers; Learning & Memory
Link ID: 18658 - Posted: 09.17.2013

By CARL ZIMMER From biology class to “C.S.I.,” we are told again and again that our genome is at the heart of our identity. Read the sequences in the chromosomes of a single cell, and learn everything about a person’s genetic information — or, as 23andme, a prominent genetic testing company, says on its Web site, “The more you know about your DNA, the more you know about yourself.” But scientists are discovering that — to a surprising degree — we contain genetic multitudes. Not long ago, researchers had thought it was rare for the cells in a single healthy person to differ genetically in a significant way. But scientists are finding that it’s quite common for an individual to have multiple genomes. Some people, for example, have groups of cells with mutations that are not found in the rest of the body. Some have genomes that came from other people. “There have been whispers in the matrix about this for years, even decades, but only in a very hypothetical sense,” said Alexander Urban, a geneticist at Stanford University. Even three years ago, suggesting that there was widespread genetic variation in a single body would have been met with skepticism, he said. “You would have just run against the wall.” But a series of recent papers by Dr. Urban and others has demonstrated that those whispers were not just hypothetical. The variation in the genomes found in a single person is too large to be ignored. “We now know it’s there,” Dr. Urban said. “Now we’re mapping this new continent.” Dr. James R. Lupski, a leading expert on the human genome at Baylor College of Medicine, wrote in a recent review in the journal Science that the existence of multiple genomes in an individual could have a tremendous impact on the practice of medicine. “It’s changed the way I think,” he said in an interview. Scientists are finding links from multiple genomes to certain rare diseases, and now they’re beginning to investigate genetic variations to shed light on more common disorders. © 2013 The New York Times Company

Keyword: Genes & Behavior
Link ID: 18657 - Posted: 09.17.2013

By Associated Press, Former Grateful Dead drummer Mickey Hart has a new piece of equipment accompanying him on his latest tour: a cap fitted with electrodes that capture his brain activity and direct the movements of a light show while he’s jamming on stage. The sensor-studded headgear is an outgrowth of collaboration between Hart, 70, and Adam Gazzaley, a University of California at San Francisco neuroscientist who studies cognitive decline. The subject has been an interest of the musician’s since the late 1980s, as he watched his grandmother deal with Alzheimer’s disease. When he played the drums for her, he says, she became more responsive. Since then, Hart has invested time and money exploring the therapeutic potential of rhythm. Thirteen years ago, he founded Rhythm for Life, a nonprofit promoting drum circles for the elderly. Hart first publicly wore his electroencephalogram cap last year at an AARP convention where he and Gazzaley discussed their joint pursuit of research on the link between brain waves and memory. He wore it again while making his new album, “Superorganism,” translating the rhythms of his brain waves into music. Hart’s bandmates, with input from other researchers in Gazzaley’s lab, paired different waves with specific musical sequences that were then inserted into songs. © 1996-2013 The Washington Post

Keyword: Brain imaging; Robotics
Link ID: 18656 - Posted: 09.17.2013

By JOHN TIERNEY Long before he brought people into his laboratory at Columbia University to smoke crack cocaine, Carl Hart saw its effects firsthand. Growing up in poverty, he watched relatives become crack addicts, living in squalor and stealing from their mothers. Childhood friends ended up in prisons and morgues. Carl Hart, an associate professor of psychology at Columbia, arranged experiments in which drug addicts were offered a choice between a dose of the drug or cash or vouchers. When the dose was smaller, addicts often chose cash or vouchers instead. Those addicts seemed enslaved by crack, like the laboratory rats that couldn’t stop pressing the lever for cocaine even as they were starving to death. The cocaine was providing such powerful dopamine stimulation to the brain’s reward center that the addicts couldn’t resist taking another hit. At least, that was how it looked to Dr. Hart when he started his research career in the 1990s. Like other scientists, he hoped to find a neurological cure to addiction, some mechanism for blocking that dopamine activity in the brain so that people wouldn’t succumb to the otherwise irresistible craving for cocaine, heroin and other powerfully addictive drugs. But then, when he began studying addicts, he saw that drugs weren’t so irresistible after all. “Eighty to 90 percent of people who use crack and methamphetamine don’t get addicted,” said Dr. Hart, an associate professor of psychology. “And the small number who do become addicted are nothing like the popular caricatures.” © 2013 The New York Times Company

Keyword: Drug Abuse
Link ID: 18655 - Posted: 09.17.2013

By Philip Yam The harvest moon is almost upon us—specifically, September 19. It’s the full moon closest to the autumnal equinox, and it has deep significance in our cultural histories. Namely, it enabled our ancestral farmers to toil longer in the fields. (Today, electricity enables us to toil longer in the office—thanks, Tom Edison.) One enduring belief is that the harvest moon is bigger and brighter than any other full moon. That myth is probably the result of the well-known illusion in which the moon looks bigger on the horizon than it does overhead. Back when I was taking psych 101, my professor explained that the moon illusion was simply a function of having reference objects on the horizon. But then I saw this TED-Ed video by Andrew Vanden Heuvel. It turns out that the explanation from my college days really isn’t sufficient to explain the illusion. In fact, scientists really aren’t sure, and there is much debate. Check it out and see what you think. © 2013 Scientific American

Keyword: Vision; Attention
Link ID: 18654 - Posted: 09.17.2013

By JAMES GORMAN In the first hint of how the Brain Initiative announced by President Obama in April could take shape, an advisory group on Monday recommended that the main target of research by the National Institutes of Health should be systems and circuits involving thousands to millions of brain cells — not the entire brain or individual cells and molecules. The National Institutes of Health working group was meant to focus specifically on how the federal agency should spend its $40 million brain initiative budget in 2014. However, Dr. Rafael Yuste, a neuroscientist at Columbia University who was not a member of the group, said that the recommendations, which he agreed with, were so ambitious that it “could be a charter for neuroscience for the next 10 to 15 years.” Dr. Francis S. Collins, director of the N.I.H., who accepted the report and its recommendations, said that he had asked the group, led by Cori Bargmann of Rockefeller University and Bill Newsome of Stanford, to think big, and that it would be the job of the N.I.H. to make actual spending decisions. Dr. Bargmann agreed that the overall goal of figuring out “how circuits in the brain generate complex thoughts and behavior” was not something to be tackled with the $40 million that the N.I.H. hopes to have for 2014. “You can’t do all of that in year one, you can’t do all of that with $40 million, and you can’t do all of that at N.I.H. either,” she said. The $40 million for the N.I.H. is part of a White House proposal for $100 million in spending on the initiative in the 2014 budget. The initiative also includes money for the National Science Foundation and the Defense Advanced Research Projects Agency. Several major private research foundations are also joining in the effort with their own research. © 2013 The New York Times Company

Keyword: Brain imaging
Link ID: 18653 - Posted: 09.17.2013

By Jay Van Bavel and Dominic Packer On the heels of the decade of the brain and the development of neuroimaging, it is nearly impossible to open a science magazine or walk through a bookstore without encountering images of the human brain. As prominent neuroscientist, Martha Farah, remarked “Brain images are the scientific icon of our age, replacing Bohr’s planetary atom as the symbol of science”. The rapid rise to prominence of cognitive neuroscience has been accompanied by an equally swift rise in practitioners and snake oil salesmen who make promises that neuroimaging cannot yet deliver. Critics inside and outside of the discipline have both been swift to condemn sloppy claims that MRI can tell us who we plan to vote for, if we love our iPhones, and why we believe in God. Yet, the constant parade of overtrumped results has lead to the rise of “The new neuro-skeptics” who argue that neuroscience is either unable to answer the interesting questions, or worse, that scientists have simply been seduced by the flickering lights of the brain. The notion that MRI images have attained an undue influence over scientists, granting agencies, and the public gained traction in 2008 when psychologists David McCabe and Alan Castel published a paper showing that brain images could be used to deceive. In a series of experiments, they found that Colorado State University undergraduates rated descriptions of scientific studies higher in scientific reasoning if they were accompanied by a 3-D image of the brain (see Figure), rather than a mere bar graph or a topographic map of brain activity on the scalp (presumably from electroencephalography). © 2013 Scientific American

Keyword: Brain imaging; Attention
Link ID: 18652 - Posted: 09.17.2013

By Melissa Hogenboom Science reporter, BBC News Smaller animals tend to perceive time in slow-motion, a new study has shown. This means that they can observe movement on a finer timescale than bigger creatures, allowing them to escape from larger predators. Insects and small birds, for example, can see more information in one second than a larger animal such as an elephant. The work is published in the journal Animal Behaviour. "The ability to perceive time on very small scales may be the difference between life and death for fast-moving organisms such as predators and their prey," said lead author Kevin Healy, at Trinity College Dublin (TCD), Ireland. The reverse was found in bigger animals which may miss things that smaller creatures can rapidly spot. In humans, too, there is variation among individuals. Athletes, for example, can often process visual information more quickly. An experienced goalkeeper would therefore be quicker than others in observing where a ball comes from. The speed at which humans absorb visual information is also age-related, said Andrew Jackson, a co-author of the work at TCD. "Younger people can react more quickly than older people, and this ability falls off further with increasing age." The team looked at the variation of time perception across a variety of animals. They gathered datasets from other teams who had used a technique called critical flicker fusion frequency, which measures the speed at which the eye can process light. BBC © 2013

Keyword: Attention; Vision
Link ID: 18651 - Posted: 09.16.2013

By JAN HOFFMAN When Vinnie Richichi started watching the Pittsburgh Steelers’ home opener against the Tennessee Titans last Sunday, he was feeling great. After all, the Steelers had won their first home game six years in a row. Then things indeed went south. “The worse they looked, the more I kept going to the fridge,” recalled Mr. Richichi, a co-host of a sports talk show on KDKA-FM in Pittsburgh. “First a couple of Hot Pockets. By the second quarter I threw in a box of White Castle hamburgers. As the game progressed, I just went through the refrigerator: the more fear, the more emotion, I’m chomping down. But I’m not going near the salad or the yogurt. If it doesn’t have 700 calories, I’m going right past it.” The aftereffect of the Steelers’ ignominious defeat by a score of 16-9 clung to Mr. Richichi on Monday, when he rejected his regular breakfast of yogurt and strawberries in favor of a bagel sandwich with sausage, eggs, cheese, peppers and hot sauce. Then, his mood hardly improved after spending four hours on the air railing and commiserating with Steelers’ fans, he had pizza for lunch. “My weight goes up and down with my teams, “ said Mr. Richichi. “My team does well? I’m 40, 50 pounds lighter.” Mr. Richichi’s eating habits, joined at the waistline with the N.F.L., were reflected in a recent study that investigated whether a football team’s outcome had an effect on what fans ate the day after a game. Although the study did not look at weight fluctuations, researchers found that football fans’ saturated-fat consumption increased by as much as 28 percent following defeats and decreased by 16 percent following victories. The association was particularly pronounced in the eight cities regarded as having the most devoted fans, with Pittsburgh often ranked No. 1. Narrower, nail-biting defeats led to greater consumption of calorie and fat-saturated foods than lopsided ones. Copyright 2013 The New York Times Company

Keyword: Obesity; Aggression
Link ID: 18650 - Posted: 09.16.2013

by Andy Coghlan A girl who does not feel physical pain has helped researchers identify a gene mutation that disrupts pain perception. The discovery may spur the development of new painkillers that will block pain signals in the same way. People with congenital analgesia cannot feel physical pain and often injure themselves as a result – they might badly scald their skin, for example, through being unaware that they are touching something hot. By comparing the gene sequence of a girl with the disorder against those of her parents, who do not, Ingo Kurth at Jena University Hospital in Germany and his colleagues identified a mutation in a gene called SCN11A. This gene controls the development of channels on pain-sensing neurons. Sodium ions travel through these channels, creating electrical nerve impulses that are sent to the brain, which registers pain. Overactivity in the mutated version of SCN11A prevents the build-up of the charge that the neurons need to transmit an electrical impulse, numbing the body to pain. "The outcome is blocked transmission of pain signals," says Kurth. To confirm their findings, the team inserted a mutated version of SCN11A into mice and tested their ability to perceive pain. They found that 11 per cent of the mice with the modified gene developed injuries similar to those seen in people with congenital analgesia, such as bone fractures and skin wounds. They also tested a control group of mice with the normal SCN11A gene, none of which developed such injuries. © Copyright Reed Business Information Ltd.

Keyword: Pain & Touch; Genes & Behavior
Link ID: 18649 - Posted: 09.16.2013

By PAULINE W. CHEN, M.D. One afternoon at a school not far from the hospital where I was working, a teacher opened a utility closet and found a staff member passed out on the floor. He was clutching a small bloody mass in one hand, a sharp knife in the other, she reported, a red stain spreading rapidly at his middle. He had amputated his genitals. Once he’d been brought to our emergency room and resuscitated, the man refused further treatment. Doctors and nurses, concerned that if they waited any longer to reattach the severed part the surgery might not work, took the necessary steps to deem him mentally incompetent to make such decisions. “The guy was seriously nuts,” I remember one of the doctors saying afterward. “He kept screaming that he didn’t want ‘it’ back.” For days after the successful operation, the gruesome story was all anyone at the hospital could discuss. Most of us chalked it up to his being “certifiable,” and several wondered if maybe they should have skipped the surgery. “After all,” said one clinician, “isn’t that what he wanted?” But in all the chatter none of us mentioned a key part of the patient’s story: the unbearable suffering that must have pushed him to commit so brutal an act. In fact, anyone overhearing our conversations might have been hard pressed to find any of the warmth and sensitivity we routinely displayed toward patients with cancer, AIDS or heart disease. I remembered the man and our reactions this past week while reading “Falling Into the Fire: A Psychiatrist’s Encounters With the Mind in Crisis,” a thought-provoking new book by Dr. Christine Montross. Of all the afflictions that fall upon us, few remain as misunderstood and stigmatized as those that affect the mind. Copyright 2013 The New York Times Company

Keyword: Schizophrenia; Depression
Link ID: 18648 - Posted: 09.16.2013

By Tina Hesman Saey About 10 percent of people prefer using their left hand. That ratio is found in every population in the world and scientists have long suspected that genetics controls hand preference. But finding the genes has been no simple task, says Chris McManus, a neuropsychologist at University College London who studies handedness but was not involved in the new research. “There’s no single gene for the direction of handedness. That’s clear,” McManus says. Dozens of genes are probably involved, he says, which means that one person’s left-handedness might be caused by a variant in one gene, while another lefty might carry variants in an entirely different gene. To find handedness genes, William Brandler, a geneticist at the University of Oxford, and colleagues conducted a statistical sweep of DNA from 3,394 people. Statistical searches such as this are known as genome-wide association studies; scientists often do such studies to uncover genes that contribute to complex diseases or traits such as diabetes and height. The people in this study had taken tests involving moving pegs on a board. The difference in the amount of time they took with one hand versus the other reflected how strongly left- or right-handed they were. A variant in a gene called PCSK6 was most tightly linked with strong hand preference, the researchers report in the Sept. 12 PLOS Genetics.. The gene has been implicated in handedness before, including in a 2011 study by the same research group. PCSK6 is involved in the asymmetrical positioning of internal organs in organisms from snails to vertebrates. © Society for Science & the Public 2000 - 2013

Keyword: Laterality; Genes & Behavior
Link ID: 18647 - Posted: 09.14.2013

Emily Underwood Jackie Murphy didn't worry that her son Fintan was a late talker, at least at first. Her other two children had been slow to say their first words, so it was only when the former California nurse noticed that her 20-month-old wasn't responding to his name, or even reacting to loud noises, that she became concerned. "One day, I dropped a toy xylophone behind him and he didn't even flinch," she says. "That's when I knew something was wrong." Fintan didn't have a hearing problem—he had autism, his mom finally learned after more than 6 months of searching for a diagnosis. A few months later, Murphy enrolled Fintan in the Autism Phenome Project at the MIND Institute at the University of California (UC), Davis, a long-term assessment of children, as many as 1800, aimed at teasing out subtypes of the complex disorder. Murphy also became a research subject, donating a blood sample. One of the project's researchers, Melissa Bauman, soon informed Murphy that her blood had tested positive for antibodies that react to fetal brain proteins. Bauman asked her to donate more blood for studies exploring the provocative idea that some of Murphy's antibodies had slipped through the placenta and into Fintan's developing brain, affecting its maturation. At that point, Murphy says, she and her husband made a big decision: Fearing that the immune proteins in her blood would harm another baby, they decided that she would not again get pregnant. Many more women could face a similarly difficult choice. In July, immunologist Judy Van de Water and her team at UC Davis, which includes Bauman and Daniel Braunschweig, bolstered the hypothesis that maternal antibodies cause some autism with two studies, including one showing autismlike symptoms in monkeys injected with such antibodies. And women may soon be able to check whether they have the suspect antibodies: California company Pediatric Bioscience announced that it is moving forward with a new diagnostic test, based on patented antibody screening techniques licensed from Van de Water and UC Davis. © 2013 American Association for the Advancement of Science

Keyword: Autism; Neuroimmunology
Link ID: 18646 - Posted: 09.14.2013

By Philip Yam If you’re a fan of optical illusions and perceptual tricks, check out this AsapSCIENCE video. As usual, producers Michael Moffitt and Gregory Brown do a great job distilling the essential ideas and presenting them in a fun, entertaining and informative way. Here, they show you how your brain judges brightness and color in context. Visit their YouTube channel to see more (including a frequency test for your ears). You can also check out our compilation of the 169 best illusions (ia sampling of them is on our site) as well as our Illusions Chasers blog, by Susana Martinez-Conde and Steven Macknik, which explore illusions each week. © 2013 Scientific American

Keyword: Vision
Link ID: 18645 - Posted: 09.14.2013

Insect leg cogs a first in animal kingdom Philip Ball If you are a young plant hopper, leaping one metre in a single bound, you need to push off with both hind legs in perfect unison or you might end up in a spin. Researchers have discovered that this synchrony is made possible by toothed gears that connect the two legs when the insects jump. Zoologists Malcolm Burrows and Gregory Sutton at the University of Cambridge, UK, say that this seems to be the first example in nature of rotary motion with toothed gears. They describe their findings today in Science1. When the insect jumps, the cog teeth join so that the two legs lock together, ensuring that they thrust at exactly the same time (see video above and image at left). “The gears add an extra level of synchronization beyond that which can be achieved by the nervous system,” says Burrows. Infant plant hoppers, known as nymphs, can take off in just 2 milliseconds, reaching take-off speeds of almost 4 metres a second (see video below). For motions this rapid, some mechanical device is needed to keep the legs synchronized and to avoid lopsided jumps that might lead to the insects spinning out of control. The problem does not, however, arise in all jumping insects: whereas the attachments of plant hoppers' hind legs are adjacent to each other, the legs of grasshoppers and fleas attach to opposite the sides of the body and move in parallel planes. This helps to stabilize the insects and even enables them to jump one-legged. © 2013 Nature Publishing Group

Keyword: Miscellaneous
Link ID: 18644 - Posted: 09.14.2013

By Philip Yam New Hampshire health officials announced last week that hospitals in three New England states may have accidentally exposed 15 people to prions, the infectious protein that ravages the brain and leaves it full of holes. Evidently, the hospitals involved used surgical tools that had previously been deployed on a patient who officials suspect later died from a particular prion infection called sporadic Creutzfeldt-Jakob disease (CJD). As disturbing as the revelation was, it pales in comparison with the announcement in 2002, when the University of Pittsburgh Medical Center Presbyterian announced that up to 4,000 patients might have been exposed to the prion. Both incidents show that the hospital transmission of prion diseases remains an ever-present possibility, if thankfully a very unlikely one. Prions are unusual pathogens distinct from parasites, fungi, bacteria and viruses. They are misfolded proteins that can transform healthy proteins into sickly versions, leading to the death of cells. Particularly abundant in the brain, they took center stage in the late 1980s, during the mad cow outbreak in the U.K. People who ate beef from infected cows ran the risk of contracting a variant of CJD. The panic brought to light the range of prion diseases that can affect humans and animals, including one that develops spontaneously. Called sporadic CJD, this spontaneous form strikes about one in every million people each year for no apparent reason. What’s more, the brain tissue from the unlucky few can infect healthy brains—hence, the worry over surgical transmission. © 2013 Scientific American

Keyword: Prions
Link ID: 18643 - Posted: 09.14.2013

By Melissa Healy It's a question that has long fascinated and flummoxed those who study human behavior: From whence comes the impulse to dream? Are dreams generated from the brain's "top" -- the high-flying cortical structures that allow us to reason, perceive, act and remember? Or do they come from the brain's "bottom" -- the unheralded brainstem, which quietly oversees such basic bodily functions as respiration, heart rate, salivation and temperature control? At stake is what to make of the funny, sexual, scary and just plain bizarre mental scenarios that play themselves out in our heads while we sleep. Are our subconsious fantasies coming up for a breath of air, as Sigmund Freud believed? Is our brain consolidating lessons learned and pitching out unneeded data, as neuroscientists suggest? Or are dreams no more meaningful than a spontaneous run of erratic heartbeats, a hot flash, or the frisson we feel at the sight of an attractive passer-by? A study published this week in the journal Brain suggests that the impulse to dream may be little more than a tickle sent up from the brainstem to the brain's sensory cortex. The full dream experience -- the complex scenarios, the feelings of fear, delight or longing -- may require the further input of the brain's higher-order cortical areas, the new research suggests. But even people with grievous injury to the brain's prime motivational machinery are capable of dreams, the study found.

Keyword: Sleep
Link ID: 18642 - Posted: 09.14.2013