By Gary Stix In April, DARPA announced contracts for a program to develop practical methods to help someone learn more quickly. In the ensuing press coverage, the endeavor drew immediate comparisons to the The Matrix—in which Neo, the Keanu Reeves character, has his brain reprogrammed so that he instantly masters Kung Fu. DARPA is known for setting ambitious goals for its technology development programs. But it is not requiring contractors for the $50 million, four-year effort to find a way to let a special forces soldier upload neural codes to instantaneously execute a flawless Wushu butterfly kick. The agency did award contracts, though, to find some means of zapping nerves in the peripheral nervous system outside the brain to speed the rate at which a foreign language can be learned by as much as 30 percent, a still not-too-shabby goal. Sending an electrical current into the vagus nerve in the neck from a surgically implanted device is already approved for treating epilepsy and depression. The DARPA program, in tacit acknowledgement that mandatory surgery might be unacceptable for students contemplating an accelerated Mandarin class, wants to develop a non-invasive device to stimulate a peripheral nerve, perhaps in the ear. The goal is to hasten, not just the learning of foreign languages, but also to facilitate pattern recognition tasks such as combing through surveillance imagery. © 2017 Scientific American,

Keyword: Learning & Memory
Link ID: 23699 - Posted: 06.02.2017

Baby teeth from children with autism contain more toxic lead and less of the essential nutrients zinc and manganese, compared to teeth from children without autism, according to an innovative study funded by the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health. The researchers studied twins to control genetic influences and focus on possible environmental contributors to the disease. The findings, published June 1 in the journal Nature Communications, suggest that differences in early-life exposure to metals, or more importantly how a child’s body processes them, may affect the risk of autism. The differences in metal uptake between children with and without autism were especially notable during the months just before and after the children were born. The scientists determined this by using lasers to map the growth rings in baby teeth generated during different developmental periods. The researchers observed higher levels of lead in children with autism throughout development, with the greatest disparity observed during the period following birth. They also observed lower uptake of manganese in children with autism, both before and after birth. The pattern was more complex for zinc. Children with autism had lower zinc levels earlier in the womb, but these levels then increased after birth, compared to children without autism. The researchers note that replication in larger studies is needed to confirm the connection between metal uptake and autism.

Keyword: Autism; Neurotoxins
Link ID: 23698 - Posted: 06.02.2017

Sarah Marsh When depression takes hold of Helen it feels like she is drowning in a pool of water, unable to swim up to the world above. The 36-year-old former nurse has had mental health problems most of her life. No drugs, hospital stays or therapies have been able to help. Then one day, during yet another spell in hospital, her consultant told her about a psychiatrist treating patients with ketamine. The psychiatrist in question visited her to discuss using the drug. He warned there were no guarantees, but it had helped some patients. Since then Helen’s life has transformed. Sitting on a bench in the grounds of the hospital where her treatment began a year and a half ago, she lists everything she can do now that she could not before: take her kids to school, give them hugs, go on coffee dates. “I am managing my thoughts and that is what ketamine helps to do. It slows down my thought process so instead of being completely overwhelmed by all these immense negative thoughts and feelings … I can think, stop and breathe,” she says, nervously pulling her sleeves over her hands as she talks. She adds: “It’s still really hard but now there is a tiny fraction of a second where my thoughts are slow enough to think: ‘I can deal with this. I cannot give up.’”

Keyword: Depression; Drug Abuse
Link ID: 23697 - Posted: 06.02.2017

By Ashley Yeager A database of electron microscopy images reveals the connections of the entire female fruit fly brain. In this image, types of Kenyon cells (KC) in the mushroom body main calyx are labeled by color: αβc-KCs are green, αβs-KCs are yellowish brown, and gamma-KCs are blue. The white arrows point to visible presynaptic release sites.ZHENG ET AL. 2017A 21-million-image dataset of the female fruit fly brain is offering an unprecedented view of the cells and their connections that underlie the animal’s behavior. The full-brain survey, taken by electron microscopy, allowed researchers to describe all of the neural inputs into a region of the fly’s brain linked to learning, examine how tightly neurons are clustered in the area, and identify a new cell type. “This is the biggest whole brain imaged at high resolution,” Davi Bock of the Janelia Research Campus in Ashburn, VA, tells The Scientist. He and his colleagues published a preprint of their results on bioRxiv this month (May 22). Past studies have produced electron microscopy images with resolution high enough to reveal the wiring of the entire brain of smaller organisms, such as a nematode or a fruit fly larva, or sections from larger animals, including parts of the fly brain or a cat’s thalamus. Imaging the complete fruit fly brain “is nearly two orders of magnitude larger than the next-largest complete brain imaged at sufficient resolution to trace synaptic connectivity,” Bock and colleagues wrote in their report. © 1986-2017 The Scientist

Keyword: Brain imaging
Link ID: 23696 - Posted: 06.02.2017

By Amina Zafar, CBC News When men postpone meal times, it delays one of the body's clocks, British researchers say, a finding that sheds light on a potential way to overcome jet lag and health harms for shift workers. Our bodies run a roughly 24-hour cycle called the circadian or sleep/wake rhythm. It is controlled by a master "clock" in the brain that responds to light signals from the retina, synchronizing other clocks throughout the body. Now investigators have discovered that a five-hour delay in meal time causes a five-hour delay in blood glucose rhythms. "We think this is due to changes in clocks in our metabolic tissues but not the 'master' clock in the brain," said Jonathan Johnston of the University of Surrey, one of the authors of the study published in Thursday's issue of the journal Current Biology. "This work is important because it demonstrates for the first time that a relatively subtle change of standard human feeding pattern re-synchronizes key metabolic rhythms in the body." Currently, people disoriented by the sluggish time warp of jet lag may take melatonin supplements and time their light exposure to help synchronize their clocks. While the study introduces the idea of adding meal timing to the clock reset toolkit, the practical details of how to do so still need to be worked out. In the experiment, 10 healthy young men came to a specialized sleep lab for 13 days. At first, breakfast was set for 30 minutes after waking. Then, after the men got used ©2017 CBC/Radio-Canada.

Keyword: Biological Rhythms; Obesity
Link ID: 23695 - Posted: 06.02.2017

By Matthew Hutson The life of a sheep is not as cushy as it looks. They suffer injury and infection, and can’t tell their human handlers when they’re in pain. Recently, veterinarians have developed a protocol for estimating the pain a sheep is in from its facial expressions, but humans apply it inconsistently, and manual ratings are time-consuming. Computer scientists at the University of Cambridge in the United Kingdom have stepped in to automate the task. They started by listing several “facial action units” (AUs) associated with different levels of pain, drawing on the Sheep Pain Facial Expression Scale. They manually labeled these AUs—nostril deformation, rotation of each ear, and narrowing of each eye—in 480 photos of sheep. Then they trained a machine-learning algorithm by feeding it 90% of the photos and their labels, and tested the algorithm on the remaining 10%. The program’s average accuracy at identifying the AUs was 67%, about as accurate as the average human, the researchers will report today at the IEEE International Conference on Automatic Face and Gesture Recognition in Washington, D.C. Ears were the most telling cue. Refining the training procedure further boosted accuracy. Given additional labeled images, the scientists expect their method would also work with other animals. Better diagnosis of pain could lead to quicker treatment. © 2017 American Association for the Advancement of Science. A

Keyword: Pain & Touch
Link ID: 23694 - Posted: 06.02.2017

By Bob Grant Prosthetic limbs are rejected by amputees’ bodies at a rate of about 20 percent. Researchers at MIT are seeking to reduce that number, using an amputation procedure that encourages increased feedback between muscles, tendons, and the nervous system so that an artificial limb might stimulate them in a more natural way—giving patients a better sense of proprioception, or where their limb is in space. The key to the surgical technique, demonstrated in rats so far, is to emulate the normal agonist-antagonist pairing of muscles (think biceps and triceps) at the amputation site so that the muscles and nerves surrounding a prosthetic can sense and transmit proprioceptive information about the artificial limb and how much force is being applied to it. The researchers published their work today (May 31) in Science Robotics. “We’re talking about a dramatic improvement in patient care,” Hugh Herr, an MIT professor of media arts and sciences and a coauthor of the study, said in a statement. “Right now there’s no robust neural method for a person with limb amputation to feel proprioceptive positions and forces applied to the prosthesis. Imagine how that would completely hinder one’s ability to move, to successfully balance, or to manipulate objects.” Herr, himself a double-amputee, and his team operated on seven rats, cutting through muscles and nerves in their hind legs. The researchers then grafted on paired muscles, wiring them up to severed nerves. After healing for four months, the rats’ new muscles were contracting and relaxing in tandem, as in naturally paired muscles, and sending electrical signals that reflected the amplitude of the artificial stimulation Herr and his colleagues applied. © 1986-2017 The Scientist

Keyword: Movement Disorders
Link ID: 23693 - Posted: 06.02.2017

Hannah Devlin Science correspondent “Love looks not with the eyes, but with the mind. And therefore is winged Cupid painted blind,” Shakespeare wrote. Now scientists have pinpointed the specific patterns of brain activity that accompany romance, offering a new explanation for why love sends our judgement haywire. As a relationship takes root, the study found, the brain’s reward circuit goes into overdrive, rapidly increasing the value placed on spending time with one’s love interest. This, at least, was the case in the prairie vole, scientists’ animal model of choice for studying the neuroscience of love. Elizabeth Amadei, who co-led the work at Emory University in Atlanta, said: “As humans, we know the feelings we get when we view images of our romantic partners, but, until now, we haven’t known how the brain’s reward system works to lead to those feelings.” In order to get more direct access to what is happening in the brain, Amadei and colleagues turned to the North American voles, which as a species have almost perfected monogamy. They mate for life, share nest-building duties and have an equal role in raising their young – although, like humans, voles have the occasional “extramarital” fling. Using electrical probes, the scientists recorded directly from the brains of female voles as they encountered a potential partner, mated for the first time and began to show signs of having formed a lifelong bond, indicated by “huddling” behaviour.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 23692 - Posted: 06.01.2017

By Mitch Leslie Colin Wahl, a market research consultant in Chapel Hill, North Carolina, was recovering nicely from triple bypass surgery last year when he noticed a white spot on the incision. It proved to be an obstinate infection that required three further surgeries to eradicate. Wahl, now 61, says his mind hasn't been as sharp since. "It's little things mostly related to memory." An avid recreational hockey player, he would forget to bring his skates or sticks to the rink. Certain words became elusive. Just hours after talking to a colleague about Tasmania, he couldn't recall the word. Instead, he says, the phrase "Outback Australia" was stuck in his mind. "I'm trying to remember something and something else slips into that memory slot." Many of us can recount a similar story about a friend, colleague, or loved one—usually elderly—whose mental condition deteriorated after a visit to an operating room. "The comment that ‘So-and-so has never been the same after the operation’ is pervasive," says anesthesiologist Roderic Eckenhoff of the University of Pennsylvania. Often, surgical patients are beset by postoperative delirium—delusions, confusion, and hallucinations—but that usually fades quickly. Other people develop what has been dubbed postoperative cognitive dysfunction (POCD), suffering problems with memory, attention, and concentration that can last months or even a lifetime. POCD not only disrupts patients' lives, but may also augur worse to come. According to a 2008 study, people who have POCD 3 months after they leave the hospital are nearly twice as likely to die within a year as are surgical patients who report no mental setbacks. With the ballooning senior population needing more surgeries, "this is going to become an epidemic," says anesthesiologist Mervyn Maze of the University of California, San Francisco. © 2017 American Association for the Advancement of Science.

Keyword: Attention; Sleep
Link ID: 23691 - Posted: 06.01.2017

By Sally Adee Older people who received transfusions of young blood plasma have shown improvements in biomarkers related to cancer, Alzheimer’s disease and heart disease, New Scientist has learned. “I don’t want to say the word panacea, but here’s something about teenagers,” Jesse Karmazin, founder of startup Ambrosia, told New Scientist. “Whatever is in young blood is causing changes that appear to make the ageing process reverse.” Since August 2016, Karmazin’s company has been transfusing people aged 35 and older with plasma – the liquid component of blood – taken from people aged between 16 and 25. So far, 70 people have been treated, all of whom paid Ambrosia to be included in the study. Karmazin spoke to New Scientist ahead of presenting some of the results from the study at the Recode conference in Los Angeles today. These results come from blood tests conducted before and a month after plasma treatment, and imply young blood transfusions may reduce the risk of several major diseases associated with ageing. Blood biomarkers None of the people in the study had cancer at the time of treatment, however Karmazin’s team looked at the levels of certain proteins called carcinoembryonic antigens. These chemicals are found in the blood of healthy people at low concentrations, but in larger amounts these antigens can be a sign of having cancer. © Copyright New Scientist Ltd.

Keyword: Alzheimers
Link ID: 23690 - Posted: 06.01.2017

Meghan Rosen The first thing you’ll notice is the noise. Monitors beep steadily, relentlessly, ready to sound a car-alarm blare if a baby is in trouble. The air has an astringent odor — not clean exactly, but reminiscent of an operating room (there’s one next door). Ceiling lights shine fluorescent white. Half are off, but glare from the monitors throws out extra light. It’s midday on a Friday, but it’ll be just as bright at midnight. Here on the fourth floor of Yale New Haven Children’s Hospital, 10 tiny beds hold 10 tiny infants, each with Band-Aid–like patches stuck to their bodies to continuously monitor health. Between beds, nurses squeeze through narrow aisles crammed with folding chairs and plastic incubators. This space, one of five in the hospital’s neonatal intensive care unit, has the people and equipment needed to keep sick babies alive — heart rate monitors, oxygen tanks, IV poles to deliver medications. Until recently, Yale’s NICU and hundreds like it across the country were considered the place to be for newborns withdrawing from opioid drugs. But now, as the number of drug-dependent babies surges, doctors here and elsewhere are searching for better options. “We’re really focused on trying to get these kids out of the NICU,” says Yale pediatrician Matthew Grossman. “We’re looking at moms and the dads as the first line of treatment.” The nationwide rate of babies withdrawing from opioids has soared — up nearly 400 percent from 2000 to 2012. The booming numbers are the bleak by-product of the United States’ ongoing battle with the drugs: Sales of prescription opioid pain relievers alone quadrupled from 1999 to 2010, and overdose deaths tripled from 2000 to 2014. © Society for Science & the Public 2000 - 2017

Keyword: Drug Abuse; Development of the Brain
Link ID: 23689 - Posted: 06.01.2017

Giuseppe Gangarossa Could it be possible to run a normal existence without social life? Indeed, sociability is an important aspect for individuals and social interaction builds our lives. In fact, social interaction enhances quality of life and improves the stability of communities. Impaired sociability is a classical symptom observed in many neuropsychiatric disorders including autism, schizophrenia, depression, anxiety and generalized fear. Interestingly, many studies have pointed to the medial prefrontal cortex (mPFC), a brain area located in the ventromedial part of the frontal lobe, as key region involved in the neural bases of sociability (Valk et al, 2015; Treadway et al., 2015; Frith et al., 2007). The prelimbic cortex (PL) and the infralimbic cortex (IL), two subregions of the mPFC, have been strongly suggested to play an important role in the neural mechanisms underlying sociability as isolation rearing in rats results in impaired social behavior and structural modifications in the PL and IL. Isolation rearing is a neurodevelopmental manipulation that produces neurochemical, structural, and behavioral alterations in rodents that in many ways are consistent with psychiatric disorders such as schizophrenia, anxiety and depression. In particular, it has been shown that isolation rearing can alter the volume of mPFC, the dendritic length and the spine density of pyramidal neurons. However, the detailed mechanisms involved in sociability disorders remain elusive and poorly understood. A recent article published in Plos ONE by Minami and colleagues aimed at measuring neural activity in the PL and IL of control and isolated rats during social interaction in order to determine whether there is neural activity related to social behavior in these areas.

Keyword: Attention
Link ID: 23688 - Posted: 06.01.2017

By Ariana Eunjung Cha Depression is usually considered an issue parents have to watch out for starting in the turbulent teenage years. The CW channel, full of characters with existential angst about school, friends and young love, tells us so, as do the countless parenting books about the adolescent years in every guidance counselor's office. But what if by that time it's already too late? A large new study out this week contains some alarming data about the state of children's mental health in the United States, finding that depression in many children appears to start as early as age 11. By the time they hit age 17, the analysis found, 13.6 percent of boys and a staggering 36.1 percent of girls have been or are depressed. These numbers are significantly higher than previous estimates. Understanding the risk of depression is critically important because of the close link between depressive episodes and serious issues with school, relationships and suicide. While researchers have long known about the gender gap in depression, with more adult women than men suffering from the condition, the new numbers show that whatever divergent paths boys and girls take happens even earlier than expected. Published in the journal Translational Psychiatry, the study was based on data compiled from in-person interviews with more than 100,000 children who participated in the National Survey of Drug Use and Health from 2009 to 2014. The NSDUH is an annual survey on a representative sample of the U.S. population. Among the standard questions asked are ones about insomnia, irritability, and feelings of guilt or worthlessness that researchers used to “diagnose” survey participants with depression using diagnostic criteria from the Diagnostic and Statistical Manual of Mental Disorders. Through the survey, they were able to capture a broader group of children than those who have a formal diagnosis and who may be in treatment. © 1996-2017 The Washington Post

Keyword: Depression; Development of the Brain
Link ID: 23687 - Posted: 06.01.2017

Laurel Hamers Last year, Joan Peay slipped on her garage steps and smashed her knee on the welcome mat. Peay, 77, is no stranger to pain. The Tennessee retiree has had 17 surgeries in the last 35 years — knee replacements, hip replacements, back surgery. She even survived a 2012 fungal meningitis outbreak that sickened her and hundreds of others, and killed 64. This knee injury, though, “hurt like the dickens.” When she asked her longtime doctor for something stronger than ibuprofen to manage the pain, he treated her like a criminal, Peay says. His response was frustrating: “He’s known me for nine years, and I’ve never asked him for pain medicine other than what’s needed after surgery,” she says. She received nothing stronger than over-the-counter remedies. A year after the fall, she still lives in constant pain. Just five years ago, Peay might have been handed a bottle of opioid painkillers for her knee. After all, opioids — including codeine, morphine and oxycodone — are some of the most powerful tools available to stop pain. Hitting opioid receptors in the peripheral nervous system keeps pain messages from reaching the brain. But opioids can cause problems by overstimulating the brain’s reward system and binding to receptors in the brain stem and gut. But an opioid addiction epidemic spreading across the United States has soured some doctors on the drugs. Many are justifiably concerned that patients will get hooked or share their pain pills with friends and family. And even short-term users risk dangerous side effects: The drugs slow breathing and can cause constipation, nausea and vomiting. |© Society for Science & the Public 2000 - 2017

Keyword: Pain & Touch; Drug Abuse
Link ID: 23686 - Posted: 05.31.2017

By David Z. Hambrick Physical similarities aside, we share a lot in common with our primate relatives. For example, as Jane Goodall famously documented, chimpanzees form lifelong bonds and show affection in much the same way as humans. Chimps can also solve novel problems, use objects as tools, and may possess “theory of mind”—an understanding that others may have different perspectives than oneself. They can even outperform humans in certain types of cognitive tasks. These commonalities may not seem all that surprising given what we now know from the field of comparative genomics: We share nearly all of our DNA with chimpanzees and other primates. However, social and cognitive complexity is not unique to our closest evolutionary cousins. In fact, it is abundant in species with which we would seem to have very little in common—like the spotted hyena. For more than three decades, the Michigan State University zoologist Kay Holekamp has studied the habits of the spotted hyena in Kenya’s Masai Mara National Reserve, once spending five years straight living in a tent among her oft-maligned subjects. One of the world’s longest-running studies of a wild mammal, this landmark project has revealed that spotted hyenas not only have social groups as complex as those of many primates, but are also capable of some of the same types of problem solving. This research sheds light on one of science’s greatest mysteries—how intelligence has evolved across the animal kingdom. According to the social brain hypothesis, intelligence has evolved to meet the demands of social life. The subject of many popular articles and books, this hypothesis posits that the complex information processing that goes along with coexisting with members of one’s own species—forming coalitions, settling disputes, trying to outwit each other, and so on—selects for larger brains and greater intelligence. By contrast, the cognitive buffer hypothesis holds that intelligence emerges as an adaption to dealing with novelty in the environment, in whatever form it presents itself. © 2017 Scientific American,

Keyword: Intelligence; Evolution
Link ID: 23685 - Posted: 05.31.2017

Nicola Davis Being in a state of anxiety makes it harder to read the emotions of others, researchers have claimed. Difficulties in interpreting the facial expressions of others have previously been linked to a number of psychiatric disorders, while people with a greater tendency to be anxious have been found to have a greater sensitivity to faces showing fear. However, it was not clear whether such effects existed among people who experience a situation that triggers anxiety. “We were specifically trying to answer the question: how does our current level of anxiety influence how we see the world, and in particular emotions in faces?” said Marcus Munafò, professor of biological psychology at the University of Bristol and a co-author of the new study. To tackle the conundrum, Munafò and colleagues from the University of Bristol looked at the impact of an anxiety-inducing situation on the ability of 21 healthy participants to interpret emotion in facial expressions. The participants’ general tendencies to worry about situations varied, but none had anxiety disorders. The participants were each fitted with a face mask delivering either normal air, or air enriched with carbon dioxide – an approach known to induce worry and tension, as well as a raised heart rate and blood pressure. After completing each part of the study, the participants repeated the experiment breathing the alternative type of air.

Keyword: Emotions
Link ID: 23684 - Posted: 05.31.2017

By Sharon Begley, STAT Living in a city makes people develop schizophrenia. Tell me more: The claim is not quite that stark, but it’s close. For a study published last week, researchers interviewed 2,063 British twins (some identical, some not) at age 18 about “psychotic experiences” they’d had since age 12—such as feeling paranoid, hearing voices, worrying their food might be poisoned, and having “unusual or frightening” thoughts. Among those who lived in the most densely populated large cities, 34 percent reported such experiences; 24 percent of adolescents in rural areas did. The twins are part of a long-running study that has followed them from birth in 1994-95, so the researchers— led by Helen Fisher of King’s College London and Candice Odgers of Duke University—also knew the teens’ family income, parents’ education, where they lived, and more. Conclusion: 18-year-olds raised in big cities were 67 percent more likely to have had psychotic experiences, the researchers reported in Schizophrenia Bulletin. They then used standard statistics tools to account for possible psychosis-related factors other than cities per se. Cities have more people who are poor and uneducated, which are risk factors for schizophrenia and other forms of psychosis, so they controlled for socioeconomic status. Family psychiatric history raises the risk of an individual’s developing psychosis, and since there is some evidence that people with mental illness move to cities, which have more treatment facilities, the researchers controlled for this, too. They also controlled for drug use, some forms of which are more common in urban than rural areas. These calculations brought the extra risk of psychosis among urban teens down to 43 percent. © 2017 Scientific American,

Keyword: Schizophrenia; Stress
Link ID: 23683 - Posted: 05.31.2017

By GRETCHEN REYNOLDS Exercise may bolster the brain function and thinking skills of people with dementia, according to a new report. The study’s findings suggest that walking a few times per week might alter the trajectory of the disease and improve the physical well-being of people who develop a common form of age-related memory loss that otherwise has few treatments. The study looked at vascular cognitive impairment, the second most frequent form of dementia worldwide, after the better-known Alzheimer’s disease. The condition arises when someone’s blood vessels become damaged and blood no longer flows well to the brain. It is often associated with high blood pressure and heart disease. One of the particular hallmarks of vascular dementia in its early stages, researchers have found, is that it tends to make the brain function less efficiently. In past brain-scan studies, people with a diagnosis of vascular cognitive impairment generally showed more neural activity in parts of their brains that are involved with memory, decision-making and attention than did people without the disease, indicating that their brains had to work harder during normal thinking than healthier brains did. But while a great deal of research attention has been devoted to Alzheimer’s disease, less has been known about the progression of and potential curbs on vascular dementia. Some research has indicated that reducing blood pressure lessens the symptoms of the disease. Exercise can likewise improve blood pressure and cardiovascular health. And some research suggests that frequent, brisk walks may improve memory and physical abilities in those in the early stages of Alzheimer’s disease. But, rather surprisingly, few past studies had examined whether exercise might also improve brain function in people with vascular dementia. So for the new study, which was published in April in The British Journal of Sports Medicine, researchers at the University of British Columbia in Canada and other institutions decided to look into the effects of walking on this type of dementia. © 2017 The New York Times Company

Keyword: Alzheimers
Link ID: 23682 - Posted: 05.31.2017

By Alice Klein A DRUG normally used to treat narcolepsy and excessive daytime sleepiness also seems to improve symptoms of attention deficit hyperactivity disorder (ADHD) symptoms. The finding supports the idea that ADHD might be a sleep disorder. People who have been diagnosed with ADHD find it difficult to concentrate and are generally hyperactive. But many with the condition also find it difficult to fall asleep and stay asleep at night, and feel drowsy during the day. Could this mean ADHD is a type of sleep disorder? After all, the brain pathways involved in paying attention have also been linked to sleep. And there’s some evidence of similarly disrupted patterns of chemical signalling in the brains of people with sleep disorders and ADHD. One suggestion is that the circadian rhythm that controls our sleep-wake cycle over each 24 hour period may be misaligned in people with ADHD, causing them to be sleepy or alert at the wrong times. This idea inspired Eric Konofal at Robert-Debré Hospital in Paris to try using a drug for narcolepsy and excessive daytime sleepiness to treat ADHD. Mazindol mimics the effects of a brain chemical called orexin, which modulates wakefulness and appetite. It works as a stimulant to keep us awake, and is lacking in people with narcolepsy, who tend to fall asleep at inappropriate times.

Keyword: ADHD; Sleep
Link ID: 23681 - Posted: 05.31.2017

By Emily Underwood Viewed under a microscope, your tongue is an alien landscape, studded by fringed and bumpy buds that sense five basic tastes: salty, sour, sweet, bitter, and umami. But mammalian taste buds may have an additional sixth sense—for water, a new study suggests. The finding could help explain how animals can tell water from other fluids, and it adds new fodder to a centuries-old debate: Does water have a taste of its own, or is it a mere vehicle for other flavors? Ever since antiquity, philosophers have claimed that water has no flavor. Even Aristotle referred to it as “tasteless” around 330 B.C.E. But insects and amphibians have water-sensing nerve cells, and there is growing evidence of similar cells in mammals, says Patricia Di Lorenzo, a behavioral neuroscientist at the State University of New York in Binghamton. A few recent brain scan studies also suggest that a region of human cortex responds specifically to water, she says. Still, critics argue that any perceived flavor is just the after-effect of whatever we tasted earlier, such as the sweetness of water after we eat salty food. “Almost nothing is known” about the molecular and cellular mechanism by which water is detected in the mouth and throat, and the neural pathway by which that signal is transmitted to the brain, says Zachary Knight, a neuroscientist at the University of California, San Francisco. In previous studies, Knight and other researchers have found distinct populations of neurons within a region of the brain called the hypothalamus that can trigger thirst and signal when an animal should start and stop drinking. But the brain must receive information about water from the mouth and tongue, because animals stop drinking long before signals from the gut or blood could tell the brain that the body has been replenished, he says. © 2017 American Association for the Advancement of Science. A

Keyword: Chemical Senses (Smell & Taste)
Link ID: 23680 - Posted: 05.31.2017