Posts tagged science
Articles and news from the latest research reports.
Brain waves reveal video game aptitude
Scientists report that they can predict who will improve most on an unfamiliar video game by looking at their brain waves. They describe their findings in a paper in the journal Psychophysiology.
The researchers used electroencephalography (EEG) to peek at electrical activity in the brains of 39 study subjects before they trained on Space Fortress, a video game developed for cognitive research. The subjects whose brain waves oscillated most powerfully in the alpha spectrum (about 10 times per second, or 10 hertz) when measured at the front of the head tended to learn at a faster rate than those whose brain waves oscillated with less power, the researchers found. None of the subjects were daily video game players.
The EEG signal was a robust predictor of improvement on the game, said University of Illinois postdoctoral researcher and Beckman Fellow Kyle Mathewson, who led the research with psychology professors and Beckman Institute faculty members Monica Fabiani and Gabriele Gratton.
“By measuring your brain waves the very first time you play the game, we can predict how fast you’ll learn over the next month,” Mathewson said. The EEG results predicted about half of the difference in learning speeds between study subjects, he said.
MRI research sheds new light on nerve fibres in the brain
World-leading experts in Magnetic Resonance Imaging from The University of Nottingham’s Sir Peter Mansfield Magnetic Resonance Centre have made a key discovery which could give the medical world a new tool for the improved diagnosis and monitoring of neuro-degenerative diseases like multiple sclerosis.
The new study, published in the Proceedings of the National Academy of Science, reveals why images of the brain produced using the latest MRI techniques are so sensitive to the direction in which nerve fibres run.
The white matter of the brain is made up of billions of microscopic nerve fibres that pass information in the form of tiny electrical signals. To increase the speed at which these signals travel, each nerve fibre is encased by a sheath formed from a fatty substance, called myelin. Previous studies have shown that the appearance of white matter in magnetic resonance images depends on the angle between the nerve fibres and the direction of the very strong magnetic field used in an MRI scanner.
Computer Simulation Shows Grandmas Made Humans Live Longer
Computer simulations provide new mathematical support for the “grandmother hypothesis” – a famous theory that humans evolved longer adult lifespans than apes because grandmothers helped feed their grandchildren.
“Grandmothering was the initial step toward making us who we are,” says Kristen Hawkes, a distinguished professor of anthropology at the University of Utah and senior author of the new study published Oct. 24 by the British journal Proceedings of the Royal Society B.
The simulations indicate that with only a little bit of grandmothering – and without any assumptions about human brain size – animals with chimpanzee lifespans evolve in less than 60,000 years so they have a human lifespan. Female chimps rarely live past child-bearing years, usually into their 30s and sometimes their 40s. Human females often live decades past their child-bearing years.
The findings showed that from the time adulthood is reached, the simulated creatures lived another 25 years like chimps, yet after 24,000 to 60,000 years of grandmothers caring for grandchildren, the creatures who reached adulthood lived another 49 years – as do human hunter-gatherers.
The grandmother hypothesis says that when grandmothers help feed their grandchildren after weaning, their daughters can produce more children at shorter intervals; the children become younger at weaning but older when they first can feed themselves and when they reach adulthood; and women end up with postmenopausal lifespans just like ours.
By allowing their daughters to have more children, a few ancestral females who lived long enough to become grandmothers passed their longevity genes to more descendants, who had longer adult lifespans as a result.
Placebo’s Effect May Depend on Your Genes
Your response to placebos, or dummy medicine, may depend on your genes, according to a new study.
People with a gene variant that codes for higher levels of the brain chemical dopamine respond better to placebos than those with the low-dopamine version.
The findings, reported online Oct. 23 in the journal PLoS One, could help researchers design medical studies that distinguish the placebo response from the underlying effect of a medicine — the real aim of drug trials.
Researchers Find That Diabetes Drug Could Be Effective in Treating Addiction
Vanderbilt researchers are reporting today that a drug currently used to treat type 2 diabetes could be just as effective in treating addiction to drugs, including cocaine.
The findings, published online as a Letter To The Editor in the journal Molecular Psychiatry, could have far-reaching implications for patients worldwide who suffer from addiction.
“What we have demonstrated is that a brain mechanism already known to be therapeutic for the treatment of diabetes also appears to be implicated in at least certain types of drug addiction,” said Gregg Stanwood, Ph.D., assistant professor of Pharmacology and an investigator within the Vanderbilt Kennedy Center and Vanderbilt Brain Institute.
“We found that this drug called Exendin-4 that is already used for the medical management of diabetes, reduces the rewarding effects of cocaine in animals. We suspect that this is a general mechanism that will translate to additional drugs of abuse, especially other stimulants like amphetamine and methamphetamine.”
Co-author Aurelio Galli, Ph.D., professor of Molecular Physiology and Biophysics and Vanderbilt Brain Institute investigator, said Exendin-4 is already FDA-approved for diabetes (Byetta and Bydureon), so this target isn’t just “druggable” – it’s already “drugged.”
“I think the power of this research is that it is so easily translatable to humans because it is already FDA approved,” said Galli, also co-director of the Neuroscience Program in Substance Abuse (N-PISA) at Vanderbilt University. “This is the first indication that it will work on psychostimulants. So our studies offer immediate translational opportunities to improve outcomes in human abusers.”
New depression treatment may avoid side-effects
In an Australian first, researchers are studying Magnetic Seizure Therapy (MST) as an alternative treatment for the 30 per cent of patients suffering from depression who don’t respond to traditional treatment.
The treating team; Anne Maree Clinton, Dr Kate Hoy and Professor Paul Fitzgerald with the MST machine
The study, led by researchers from the Monash Alfred Psychiatry Research Centre (MAPrc) and funded by beyondblue and the National Health and Medical Research Council (NHMRC), has been published in two leading journals: Psychiatry Research: Neuroimaging and Depression and Anxiety. Both papers are a result of the same study.
MAPrc Deputy Director Professor Paul Fitzgerald, who led the study, said depression was a common and disabling disorder, affecting up to one in five Australians during their lifetime.
“Electroconvulsive Therapy (ECT) is one of the only established interventions for treatment resistant depression,” Professor Fitzgerald said.
“But use of ECT is limited due to the presence of memory-related side effects and associated stigma.”
For this reason, the MAPrc researchers began exploring new treatment options. MST is a brain-stimulation technique that may have similar clinical effects to ECT without the unwanted side effects.
“In MST, a seizure is induced through the use of magnetic stimulation rather than a direct electrical current like ECT. Magnetic fields are able to pass freely into the brain, making it possible to more precisely focus stimulation,” Professor Fitzgerald said.
“By avoiding the use of direct electrical currents and inducing a more focal stimulation, it is thought that MST will result in an improvement of depressive symptoms without the memory difficulties seen with ECT.”
Research is still at an early stage and MST is only available in a handful of locations worldwide. The MAPrc is the only centre in Australia conducting trials with this therapy.
The study found that MST resulted in an overall significant reduction in depression symptoms; 40 per cent showed overall improvement and 30 per cent showed some improvement. None of the trial participants complained of cognitive side effects.
“MST shows antidepressant efficacy without apparent cognitive side effects. However, substantial research is required to understand the optimal conditions for stimulation and to compare MST to established treatments, including ECT,” Professor Fitzgerald said.
“In order to accurately assess the comparable efficacy of MST to ECT, large-scale randomised controlled trials are required. There remains considerable work to be done before statements of the relative efficacy of these treatments can be made.”
Professor Fitzgerald and his team have received more funding from beyondblue and the NHMRC to carry out a large-scale trial on MST as an alternative treatment for depression.
(Source: monash.edu.au)
New epilepsy gene discovered
In a national research partnership, Dr Sarah Heron from the University of South Australia’s Sansom Research Institute, epilepsy research group, has been working to map the genes responsible for a rare form of epilepsy - autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE).
Dr Heron and her team’s latest research to identify a new gene for this form of epilepsy has been published in Nature Genetics this month.
She says while ADNFLE affects a relatively rare group of people, the symptoms and impact of the condition can be devastating.
“ADNFLE usually develops in childhood and characterised by clusters of seizures during sleep,” Dr Heron says.
“It can have an association with cognitive deficits and or psychiatric comorbidity.
“Our research has identified that mutations in the sodium-gated potassium channel gene KCNT1 cause severe autosomal dominant nocturnal frontal lobe epilepsy and associated intellectual and or psychiatric disability.”
Dr Heron says the identification of the gene has important implications for genetic counselling and also for understanding more about the full spectrum of epilepsy disorders.
Are Schizophrenia and Autism Close Relations?
TAU researcher discovers that family history of schizophrenia is a risk factor for autism
Autism Spectrum Disorders (ASD), a category that includes autism, Asperger Syndrome, and Pervasive Developmental Disorder, are characterized by difficulty with social interaction and communication, or repetitive behaviors. The U.S. Centers for Disease Control and Management says that one in 88 children in the US is somewhere on the Autism spectrum — an alarming ten-fold increase in the last four decades.
New research by Dr. Mark Weiser of Tel Aviv University’s Sackler Faculty of Medicine and the Sheba Medical Center has revealed that ASD appears share a root cause with other mental illnesses, including schizophrenia and bipolar disorder. At first glance, schizophrenia and autism may look like completely different illnesses, he says. But closer inspection reveals many common traits, including social and cognitive dysfunction and a decreased ability to lead normal lives and function in the real world.
Studying extensive databases in Israel and Sweden, the researchers discovered that the two illnesses had a genetic link, representing a heightened risk within families. They found that people who have a schizophrenic sibling are 12 times more likely to have autism than those with no schizophrenia in the family. The presence of bipolar disorder in a sibling showed a similar pattern of association, but to a lesser degree.
A scientific leap forward, this study sheds new light on the genetics of these disorders. The results will help scientists better understand the genetics of mental illness, says Dr. Weiser, and may prove to be a fruitful direction for future research. The findings have been published in the Archives of General Psychiatry.
All in the family
Researchers used three data sets, one in Israel and two in Sweden, to determine the familial connection between schizophrenia and autism. The Israeli database alone, used under the auspices of the ethics committees of both the Sheba Medical Center and the Israeli Defense Forces, included anonymous information about more than a million soldiers, including patients with schizophrenia and ASD.
"We found the same results in all three data sets," he says, noting that the ability to replicate the findings across these extensive databases is what makes this study so significant.Understanding this genetic connection could be a missing link, Dr. Weiser says, and provides a fresh direction for study. The researchers are now taking this research in a clinical direction. For now, though, the findings shouldn’t influence the way that doctors treat patients with either illness, he adds.
(Source: aftau.org)
Perfect Pitch: Knowing the Note May Be in Your Genes
People with perfect pitch seem to possess their own inner pitch pipe, allowing them to sing a specific note without first hearing a reference tone. This skill has long been associated with early and extensive musical training, but new research suggests that perfect pitch may have as much to do with genetics as it does with learning an instrument or studying voice.
Previous research does draw a connection between early musical training and the likelihood of a person developing perfect pitch, which is also referred to as absolute pitch. This is especially true among speakers of tonal languages, such as Mandarin. Speakers of English and other non-tonal languages are far less likely to develop perfect pitch, even if they were exposed to early and extensive musical training.
“We have wondered if perfect pitch is as much about nature or nurture,” said Diana Deutsch, a professor of psychology at the University of California, San Diego. “What is clear is that musically trained individuals who speak a non-tone language can acquire absolute pitch, but it is still a remarkably rare talent. What has been less clear is why most others with equivalent musical training do not.” Deutsch and her colleague Kevin Dooley present their findings at the 164th meeting of the Acoustical Society of America (ASA), held Oct. 22 – 26 in Kansas City, Missouri.
To shine light on this question, the researchers studied 27 English speaking adults, 7 of whom possessed perfect pitch. All began extensive musical training at or before the age of 6. The researchers tested the subjects’ memory ability using a test known as the digit span, which measures how many digits a person can hold in memory and immediately recall in correct order. They presented the digits either visually or auditorily; for the auditory test, the subject listened to the numbers through headphones, and for the visual test the digits were presented successively at the center of a computer screen.
The people with perfect pitch substantially outperformed the others in the audio portion of the test. In contrast, for the visual test, the two groups exhibited very similar performance, and their scores were not significantly different from each other. This is significant because other researchers have shown previously that auditory digit span has a genetic component.
“Our finding therefore shows that perfect pitch is associated with an unusually large memory span for speech sounds,” said Deutsch, “which in turn could facilitate the development of associations between pitches and their spoken languages early in life.”
(Source: newswise.com)
Scientists Build ‘Mechanically Active’ DNA Material That Responds With Movement When Stimulated
Artificial muscles and self-propelled goo may be the stuff of Hollywood fiction, but for UC Santa Barbara scientists Omar Saleh and Deborah Fygenson, the reality of it is not that far away. By blending their areas of expertise, the pair have created a dynamic gel made of DNA that mechanically responds to stimuli in much the same way that cells do.
The results of their research were published online in the Proceedings of the National Academy of Sciences.
"This is a whole new kind of responsive gel, or what some might call a ‘smart’ material," said Saleh, associate professor of materials, affiliated with UCSB’s Biomolecular Science and Engineering program. "The gel has active mechanical capabilities in that it generates forces independently, leading to changes in elasticity or shape, when fed ATP molecules for energy — much like a living cell."
Their DNA gel, at only 10 microns in width, is roughly the size of a eukaryotic cell, the type of cell of which humans are made. The miniscule gel contains within it stiff DNA nanotubes linked together by longer, flexible DNA strands that serve as the substrate for molecular motors.
"DNA gives you a lot more design control," said Fygenson, associate professor of physics and also affiliated with UCSB’s BMSE program. "This system is exciting because we can build nano-scale filaments to specifications." Using DNA design, she said, they can control the stiffness of the nanotubes and the manner and extent of their cross-linking, which will determine how the gel responds to stimuli.