(Medical Xpress)—Two Simon Fraser University psychologists have made a brain-related discovery that could revolutionize doctors' perception and treatment of attention-deficit disorders.
This discovery opens up the possibility that environmental and/or genetic factors may hinder or suppress a specific brain activity that the researchers have identified as helping us prevent distraction.
The Journal of Neuroscience has just published a paper about the discovery by John McDonald, an associate professor of psychology and his doctoral student John Gaspar, who made the discovery during his master's thesis research.
This is the first study to reveal our brains rely on an active suppression mechanism to avoid being distracted by salient irrelevant information when we want to focus on a particular item or task.
McDonald, a Canada Research Chair in Cognitive Neuroscience, and other scientists first discovered the existence of the specific neural index of suppression in his lab in 2009. But, until now, little was known about how it helps us ignore visual distractions.
"This is an important discovery for neuroscientists and psychologists because most contemporary ideas of attention highlight brain processes that are involved in picking out relevant objects from the visual field. It's like finding Waldo in a Where's Waldo illustration," says Gaspar, the study's lead author.
The idea that tiny amounts of antidepressants present in our rivers and estuaries may be affecting aquatic life is generally met with surprise, sometimes scepticism, or even a degree of humour.
The public were first alerted to pharmaceuticals in the environment in the 1990s through studies which showed that synthetic oestrogens, such as in the contraceptive pill, could feminise male fish, even in incredibly low concentrations of nanograms per litre (ng/L). This led to concerns of a similar effect on male human fertility, although it’s been hard to draw any conclusions.
The idea that even tiny amounts of chemicals might dramatically alter the physiology of fish and other aquatic organisms isn’t that new. Back in the 1980s scientists were aware that concentrations even below 10ng/L of tributyltin or TBT, a compound used in anti-fouling paints for ships' hulls, would cause female dog whelks (a sort of sea snail) to grow a penis. This resulted in catastrophic reproductive failure in females which wiped out snail populations along the world’s coasts, which had knock-on effects on organisms further up and down the food chain.
A more recent example is diclofenac, a non-steroidal anti-inflammatory drug given to lame cattle in India and Pakistan. While considered harmless to mammals, what was not predicted was that vultures preying on dead cattle would suffer catastrophic renal failure, resulting in their populations plunging by 90%.
Some scientists have suggested that reduced vulture populations led to a boom in feral dog populations and an increase in rabies among the human population. Highly publicised, this focused people’s attention on the toxicological impact of human and veterinary drugs on wildlife.
Medical engineers said Sunday they had created a device the size of a plaster which can monitor patients by tracking their muscle activity before administering their medication.
Methods for monitoring so-called "movement disorders" such as epilepsy and Parkinson's disease have traditionally included video recordings or wearable devices, but these tend to be bulky and inflexible
The new gadget, which is worn on the skin, looks like a Band-Aid but uses nanotechnology—in which building blocks as small as atoms and molecules are harnessed to bypass problems of bulkiness and stiffness— to monitor the patient.
Scientists have long hoped to create an unobtrusive device able to capture and store medical information as well as administer drugs in response to the data.
A nasal spray containing a specially-developed protein peptide could form the basis for highly-targeted treatment for depression, new research from the Centre for Addiction and Mental Health (CAMH) has shown. The peptide, when delivered in spray from, was found to relieve symptoms of depression, with the lead researcher hopeful of little to no side-effects.
The protein peptide was originally developed in 2010 by Dr. Fang Liu, Senior Scientist in the Campbell Family Mental Health Research Institute at CAMH. While the peptide was found to be just as effective as conventional anti-depressants when tested on animals, when administered orally it was unable to cross the blood-brain barrier in sufficient concentrations and therefore had to be injected into the brain.
A grant from the Canadian Institute of Health Research then enabled Liu and a team of researchers to explore other methods of delivery. In administering the peptide in the form of a nasal spray, the team found that it was delivered to the right part of the brain to relieve depression-like symptoms in animals.
Patchy changes in the developing brain long before birth may cause symptoms of autism spectrum disorder (ASD), research suggests.
The study, in the New England Journal of Medicine, raises hopes that better understanding of the brain may improve the lives of children with autism.
It reinforces the need for early identification and treatment, says a University of California team.
US scientists analysed post-mortem brain tissue of 22 children with and without autism, all between two and 15 years of age.
They used genetic markers to look at how the outermost part of the brain, the cortex, wired up and formed layers.
Abnormalities were found in 90% of the children with autism compared with only about 10% of children without.
The changes were dotted about in brain regions involved in social and emotional communication, and language, long before birth, they say.
The researchers, from the University of California, San Diego and the Allen Institute for Brain Science in Seattle, say their patchy nature may explain why some toddlers with autism show signs of improvement if treated early enough.
They think the plastic infant brain may have a chance of rewiring itself to compensate.
Although it has long been known that dark chocolate provides numerous health benefits, the exact reason as to why this is so has remained a mystery. Now res..
It has long been known that eating chocolate, particularly dark chocolate, has numerous health benefits. Although various studies have backed this up, the exact reason as to why this is so has remained a mystery. Now researchers from Louisiana State University have provided the answer – gut microbes.
Presenting their findings at the 27th National Meeting & Exposition of the American Chemical Society (ACS), the researchers revealed that, unlike so-called "bad" bacteria in the gut, such as some Clostridia and some E. coli, that are associated with inflammation and can cause gas, bloating, diarrhea and constipation, "good" bacteria, such as Bifidobacterium and lactic acid bacteria, feed on dark chocolate to produce anti-inflammatory compounds.
As more of medicine comes into the info age, will we get better sooner? Or simply have a more detailed idea of why we're sick?
One of the things that Dr. Blumenthal didn’t include in his response was that the health care industry needs to continue to create a culture of evidence-based medicine, beyond the activities at those organizations that are further along the maturity curve regarding electronic health records and healthcare technology.
The reality is that much of healthcare is administered to patients based upon the practitioner’s experience (patients he or she has seen with similar conditions), the practitioner’s ability to accurately recall the appropriate care for the patient being seen and, where time has allowed, the opportunity to stay current on healthcare research and able to then apply that research correctly to the patient at hand.
There’s a rule of thumb in surgery—the less invasive the procedure, the better. Less invasive surgeries reduce patient discomfort, foster faster recoveries, and limit the risk of infection. Problem is, you have to get your eyes on a problem to solve it.
In heart surgery, for example, practitioners use external ultrasound to view blockages. The images are useful, but they are only good enough to serve as a general guide. Georgia Tech researchers, led by Professor F. Levent Degertekin, think they can improve the situation and even reduce the frequency of invasive heart surgery.
“If you’re a doctor, you want to see what is going on inside the arteries and inside the heart, but most of the devices being used for this today provide only cross-sectional images,” Degertekin says.
The group is building a tiny wired ultrasound device that surgeons can snake through arteries to provide a 3D, front-facing image of blockages in real time—the “equivalent of a flashlight” in the heart’s lightless passageways.
There are, of course, already internal ultrasound devices. These are used to image various organs—the stomach, for instance, by way of the esophagus. What makes this particular device special is its size and ability to travel into smaller pathways.
Once mocked as having the erotic appeal of a jellyfish, the female condom is being reinvented as the next big thing in protective sex. In the first article from new digital publication Mosaic, Emily Anthes takes an in-depth investigation to see what chance it has of catching on this time around.
In 1987, an American pharmaceutical executive called Mary Ann Leeper flew to Copenhagen to get a first-hand look at what she thought might be the world’s next great health innovation. She didn’t expect to find it tucked away inside an old cigar box.
When she arrived at the old farmhouse owned by Danish doctor and inventor Lasse Hessel, he opened the door with a cigar in his mouth. Then he fetched the box. “Inside were all these bits and pieces – metal, plastic, all different kinds of stuff,” Leeper recalls. “I took a deep breath and thought, ‘Holy mother – what have I gotten myself into?’” Somehow, these bits and pieces fit together to form a contraption that women could wear during sex to prevent pregnancy and sexually transmitted infections – the world’s first female condom.
The presentation may have been unconventional, but Leeper and her colleagues at Wisconsin Pharmacal had high hopes for Hesse’s invention. “The Aids crisis in the United States was just fully being recognised, and it was clear to us that for women to have a product that they could use to help protect themselves would be a good thing,” Leeper says.
Indeed, when Wisconsin Pharmacal finally introduced the female condom to the US in 1993, public health experts hailed it as a game-changer. The condom, a polyurethane pouch inserted into the vagina before sex, would protect women from sexually transmitted infections even if their male partners refused to wear condoms.
Technically, the female condom works. When used correctly, it reduces a woman’s risk of contracting HIV by around 94–97% each time she had sex, according to estimates. Studies show that making female condoms available alongside the male version increases the percentage of sexual acts that are protected, and decreases the prevalence of sexually transmitted infections.
Controversial technique, currently banned, would prevent women from passing mitochondrial diseases to their children
The Department of Health has launched a three-month consultation on the draft regulations for a radical procedure that aims to prevent mothers from passing on serious genetic diseases to their children, a controversial technique because it leads to babies with DNA from three people.
Mitochondrial transfer has never been tried in humans and is prohibited in Britain under laws that ban the placing of an egg or embyro into a woman if the DNA has been altered. But scientists working on the technique said it offered hope of preventing life-threatening diseases for which there were no cures.
The government announced last June that it intends to allow the procedure, but the regulations must be finalised, debated and approved by parliament before the Human Fertilisation and Embryology Authority (HFEA) can allow clinics to offer the treatment.
About one in 200 children born in the UK have some form of mitochondrial disorder. The most serious affect the heart, brain, muscles and liver. Under the procedure, the nucleus is removed from an affected woman's egg or from a cell in an embryo and transferred to a donor egg or embryo that has healthy mitochondria.
As a result, a baby will have DNA from the biological parents and a female donor who provides healthy mitochondria, the tiny biological batteries that power most cells in the body. The fraction of a cell's DNA that is in mitochondria is minuscule and affects only how cells are powered. It does not influence the child's physical appearance or personality.
Corrinne Burns: With purported activity against cardiac disease, cancer and even ageing, the pressure on resveratrol to deliver is enormous
In an increasingly chemophobic world, one chemical – resveratrol – is doing rather well for itself. This polyphenolic stilbenoid is a natural product found in peanuts, cocoa powder and the roots of Japanese knotweed, but it only came to public prominence as the health-promoting component of red wine, in which it is present at levels of up to 14 milligrams per litre, depending on the grape variety.
As molecules go, it is certainly a multitasker, with purported activity against cardiac disease, obesity, cancer, vascular dementia and ageing. That’s a lot of pressure to put on one molecule. Can resveratrol live up to our expectations?
Many of these claims centre upon its ability to reduce oxidation in cells: its fabled antioxidant activity. All molecules, including biological ones, carry around their own cloud of electrons. These are most stable when they exist in pairs. Sometimes, though, electron pairs split. Then you’re left with an unpaired electron – and unpaired electrons like nothing more than to mess with other biological molecules.
Left unchecked, molecules carrying unpaired electrons can trigger cascades of damage to other molecules in our cells. Resveratrol is thought to interrupt those destructive cascades by transferring electrons and hydrogen atoms between itself and troublesome, lone-electron-carrying molecules.
Resveratrol can do much more than that, though. It encourages the production of endothelial nitric oxide, which dilates blood vessels. Researchers have demonstrated that this ability to open up blood vessels means resveratrol can protect against hypertension – at least in rats and mice. It is also an anti-inflammatory, disrupting the activity of an enzyme called cyclooxygenase-2 (COX-2), which is crucial to the production of inflammatory prostaglandins.
Results on regenerated thymus in very old mice potentially open way for helping humans live longer
Scientists have regenerated a living organ for the first time, potentially opening the way for life-lengthening human therapies.
A team at Edinburgh University’s medical research centre for regenerative medicine managed to rebuild the thymus of very old mice, re-establishing the health of the organ seen in younger creatures.
Scientists reactivated a natural mechanism that shuts down with age to rejuvenate the thymus, an organ near the heart that produces important infection-fighting white blood cells, called T cells.
By targeting a protein called FOXN1, which helps control how genes are switched on, the function of the thymus was restored. Treated mice began to make more T cells.
The research, published in the journal Development, found the thymus grew to twice its previous size, and the recovery appeared sustainable. Scientists now will look into any unintended consequences of increasing FOXN1.
The thymus is the first organ in the human body to deteriorate as we age, contributing to the declining capacity of older people to fight off new infections, such as flu.
The breakthrough may lead to treatments that could significantly elongate human life. But this would be many years away, given that the process has been tested only on mice.
Dr. Steven Horng launched a Google Glass pilot program at Beth Israel Deaconess Medical Center late last year because he thought the futuristic device could help save lives. One night in January proved that. A patient with bleeding in the brain told Horng he was allergic to certain blood pressure drugs — which the doctor needed to slow the hemorrhage — but didn’t know which ones. Horng had little time to leaf through the man’s medical files or search for records on a computer, but with Glass, he didn’t have to. Instead he quickly called up patient’s information on the device’s tiny screen and saved his life with the correct medication. This week, Beth Israel Deaconess is expanding the use of Google Glass to its entire emergency department, and the hospital said it is the first in the United States to employ the device for everyday medical care. Now, whenever ER doctors begin their shifts, they will slip on pairs of the high-tech glasses as routinely as they put on scrubs. “We’re doing this to prove that the technology can work and really motivate others to explore this space with us,” said Horng, who helped pioneer the initial use of Google Glass at the hospital.
Centre will use latest technology to gain insights into human cognition and learn how it becomes disrupted in disorders
The worlds' first computational psychiatry centre has opened in London with a mission to shine a new light on human cognition and understand how it becomes disrupted in disorders such as depression and dementia.
Backed by a five-year €5m (£4.1m) investment from the Max Planck Society and UCL, the centre, which is named after its funders and will be based in London and Berlin, will use powerful modern technology in an effort to create more detailed models than ever before of how the human brain works.
Professor Ray Dolan, academic co-leader of the centre, said: "The brain is at some level an information processing machine and we have to understand what it's doing and how that information processor is working. We are trying to understand normal cognition with respect to the type of processes that go awry in psychiatric disorders and in ageing, we then intend to apply these models to understand ageing, depression or any other psychiatric disorders where we think the models may be appropriate. "
UK researchers say discovery suggests dietary advice should focus on genetic predisposition to digest different foods
British researchers have discovered a link between a gene that breaks down carbohydrates and obesity, which may pave the way for more effective, individually tailored diets for people wanting to lose weight.
Researchers at King's College London and Imperial College London found that people with fewer copies of a gene responsible for carbohydrate breakdown may be at higher risk of obesity. The findings, published in Nature Genetics, suggest that dietary advice may need to focus more on a person's digestive system, based on whether they have the genetic predisposition and necessary enzymes to digest different foods.
The salivary amylase gene plays a significant role in breaking down carbohydrates in the mouth at the start of the digestion process. The new study suggests that people with fewer copies of the AMY1 gene have lower levels of this enzyme and so have more difficulty breaking down carbohydrates than those with more copies.
Previous research has found a genetic link between obesity and food behaviours and appetite, but the discovery highlights a genetic link between metabolism and obesity.
The ATHENA project, which is developing a desktop human for for screening both new drugs and toxic agents, has reported success in the development of its ...
A five-year, US$19 million multi-institutional effort is working on developing a "desktop human" that could reduce the need for animal testing in the development of new drugs. The "homo minitus" is a drug and toxicity analysis system that would comprise four human organ constructs interconnected to mimic the response of human organs. The project has now reported success in the development of its first organ construct, a human liver construct that responds to exposure to a toxic chemical much like a real liver.
The miniaturized platform being developed through the Advanced Tissue-engineered Human Ectypal Network Analyzer project (ATHENA) will see each organ component shrunk to the roughly the size of a smartphone screen, with each of the components connected by tubing infrastructure that mimics the way the real organs are connected in the human body by blood vessels. The entire "ATHENA" body would be compact enough to fit on a desk or bench.
"By developing this 'homo minutus,' we are stepping beyond the need for animal or Petri dish testing," says Rashi Iyer, a senior scientist at Los Alamos National Laboratory (LANL), the lead laboratory on the project that is supported by the Defense Threat Reduction Agency (DTRA). "There are huge benefits in developing drug and toxicity analysis systems that can mimic the response of actual human organs."
iHear, an invisible hearing aid, is designed to significantly lower the cost of personalized hearing devices by enabling the user to test the extent of thei...
According to the Hearing Loss Association of America, 48 million Americans (around 20 percent of the population) report some degree of hearing loss. This problem is compounded by the costs associated with having the condition diagnosed and a hearing aid fitted in a clinic, causing many to allow the ailment to go untreated. iHear, an invisible hearing aid, is designed to significantly lower the cost of personalized hearing devices by enabling the user to test the extent of their condition and calibrate the hearing aid from their own home.
(Medical Xpress)—New research shows that, contrary to what was previously assumed, suppressing unwanted memories reduces their influence on behaviour, and sheds light on how this process happens in the brain.
The study, published online in PNAS, challenges the idea that suppressed memories remain fully preserved in the brain's unconscious, allowing them to be inadvertently expressed in someone's behaviour. The results of the study suggest instead that the act of suppressing intrusive memories helps to disrupt traces of the memories in the parts of the brain responsible for sensory processing.
The team at the MRC Cognition and Brain Sciences Unit and the University of Cambridge's Behavioural and Clinical Neuroscience Institute (BCNI) have examined how suppression affects a memory's unconscious influences in an experiment that focused on suppression of visual memories, as intrusive unwanted memories are often visual in nature.
After a trauma, most people report intrusive memories or images, and people will often try to push these intrusions from their mind, as a way to cope. Importantly, the frequency of intrusive memories decreases over time for most people. It is critical to understand how the healthy brain reduces these intrusions and prevents unwanted images from entering consciousness, so that researchers can better understand how these mechanisms may go awry in conditions such as post-traumatic stress disorder.
Participants were asked to learn a set of word-picture pairs so that, when presented with the word as a reminder, an image of the object would spring to mind. After learning these pairs, brain activity was recorded using functional magnetic resonance imaging (fMRI) while participants either thought of the object image when given its reminder word, or instead tried to stop the memory of the picture from entering their mind.
Obesity may have harmful effects on the brain, and exercise may counteract many of those negative effects, according to sophisticated new neurological experiments with mice, even when the animals do not lose much weight. While it’s impossible to know if human brains respond in precisely the same way to fat and physical activity, the findings offer one more reason to get out and exercise.
It’s been known for some time that obesity can alter cognition in animals. Past experiments with lab rodents, for instance, have shown that obese animals display poor memory and learning skills compared to their normal-weight peers. They don’t recognize familiar objects or recall the location of the exit in mazes that they’ve negotiated multiple times.
But scientists hadn’t understood how excess weight affects the brain. Fat cells, they knew, manufacture and release substances into the bloodstream that flow to other parts of the body, including the heart and muscles. There, these substances jump-start biochemical processes that produce severe inflammation and other conditions that can lead to poor health.
Many thought the brain, though, should be insulated from those harmful effects. It contains no fat cells and sits behind the protective blood-brain barrier that usually blocks the entry of undesirable molecules.
However, recent disquieting studies in animals indicate that obesity weakens that barrier, leaving it leaky and permeable. In obese animals, substances released by fat cells can ooze past the barrier and into the brain.
Tailor-made medical devices could give a more detailed picture of cardiac health and may be better at predicting and preventing problems.
It’s a poetic fact of biology that everyone’s heart is a slightly different size and shape. And yet today’s cardiac implants—medical devices like pacemakers and defibrillators—are basically one size fits all. Among other things, this means these devices, though lifesaving for many patients, are limited in the information they can gather.
Researchers recently demonstrated a new kind of personalized heart sensor as part of an effort to change that. The researchers used images of animals’ hearts to create models of the organ using a 3-D printer. Then they built stretchy electronics on top of those models. The stretchy material can be peeled off the printed model and wrapped around the real heart for a perfect fit.
The research team has also integrated an unprecedented number of components into these devices, demonstrating stretchy arrays of sensors, oxygenation detectors, strain gauges, electrodes, and thermometers made to wrap perfectly around a particular heart. For patients, this could mean more thorough, better-tailored monitoring and treatment.
One device in need of improvement is the implanted defibrillator, which is attached to a misfiring heart and uses readings from one or two electrodes to determine whether to restore a normal heartbeat by applying an electric shock. With information from just one or two points, the electronics in these systems can make the wrong decision, giving the patient a painful unnecessary shock, says Igor Efimov, a cardiac physiologist and bioengineer at Washington University in St. Louis.
An ancient virus has come back to life after lying dormant for at least 30,000 years, scientists say.
It was found frozen in a deep layer of the Siberian permafrost, but after it thawed it became infectious once again.
The French scientists say the contagion poses no danger to humans or animals, but other viruses could be unleashed as the ground becomes exposed.
The study is published in the Proceedings of the National Academy of Sciences (PNAS).
Professor Jean-Michel Claverie, from the National Centre of Scientific Research (CNRS) at the University of Aix-Marseille in France, said: "This is the first time we've seen a virus that's still infectious after this length of time."