Posts tagged psychology
Articles and news from the latest research reports.
Brainwave Training Boosts Network for Cognitive Control and Predicts Mind Wandering
A breakthrough study conducted in Canada has found that training of the well-known brainwave in humans, the alpha rhythm, enhances a brain network responsible for cognitive-control which correlates with reductions in mind-wandering. The training technique, termed neurofeedback, is being considered as a promising method for restoring brain function in mental disorders. Using several neuroimaging methods, a team of researchers working at the University of Western Ontario have now uncovered that functional changes within a key brain network occur directly after a 30-minute session of noninvasive, neural-based training. Dysfunction of this cognitive-control network has previously been implicated in a range of brain disorders including attentional deficit hyperactivity disorder, schizophrenia, depression and post-traumatic stress disorder.
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.
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.
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)
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)
Why Some People See Sound
Some people may actually see sounds, say researchers who found this odd ability is possible when the parts of the brain devoted to vision are small.
These findings points to a clever strategy the brain might use when vision is unreliable, investigators added.
Scientists took a closer look at the sound-induced flash illusion. When a single flash is followed by two bleeps, people sometimes also see two illusory consecutive flashes.
Past experiments revealed there are strong differences between individuals when it comes to how prone they are to this illusion. “Some would experience it almost every time a flash was accompanied by two bleeps, others would almost never see the second flash,” said researcher Benjamin de Haas, a neuroscientist at University College London.
These differences suggested to de Haas and his colleagues that maybe variations in brain anatomy were behind who saw the illusion and who did not. To find out, the researchers analyzed the brains of 29 volunteers with magnetic resonance imaging (MRI) and tested them with flashes and bleeps.
On average, the volunteers saw the illusion 62 percent of the time, although some saw it only 2 percent of the time while others saw it 100 percent of the time. They found the smaller a person’s visual cortex was — the part of the brain linked with vision —the more likely he or she experienced the illusion."If we both look at the same thing, we would expect our perception to be identical," de Haas told LiveScience. "Our results demonstrate that this not quite true in every situation — sometimes what you perceive depends on your individual brain anatomy."
The researchers suggest this illusion could reveal a way the brain compensates for imperfect visual circuitry.
Electrical stimulation of brain area causes strange visual illusions
A new study shows that electrical stimulation of a small patch of the brain causes illusions that only affect the perception of faces. (Matt Cardy/Getty Images)
Ron Blackwell didn’t enter the hospital expecting to see his doctor’s face melt before his eyes. But that’s exactly what happened when researchers electrically stimulated a small part of his brain, according to a study published Tuesday in the Journal of Neuroscience.
The doctor’s face did not actually melt, of course. Instead, the researchers argue, the stimulation short-circuited a brain area called the fusiform gyrus. Previous studies have linked a part of that area to face processing by showing that it becomes active when people perceive faces. But it’s hard to know just how important the area is for facial processing unless you can actually change its activity level while someone views faces.
Blackwell, an epileptic, turned out to be the perfect test case. He was in Stanford’s hospital so that doctors — including the study author, Dr. Josef Parvizi — could study his epilepsy and decide whether they could perform surgery to remove the part of the brain responsible for his seizures. As part of that procedure, Parvizi laid down a strip of electrodes on the surface of the brain. That gave him the capacity to painlessly and harmlessly stimulate the part of the brain they covered, and one of those electrodes was right over the fusiform gyrus.
Along with collaborators led by Stanford psychologist Kalanit Grill-Spector, Parvizi stimulated the area to see whether it would affect Blackwell’s perception of the doctor’s face. When he performed a sham stimulation — counting down from three and pressing a button that did nothing — Blackwell reported no change.
But when Parvizi applied voltage, strange things suddenly began to happen to Blackwell’s face perception. “You just turned into somebody else,” Blackwell said in a video that was recorded as part of the experiment. “Your face metamorphosed. Your nose got saggy, went to the left. You almost looked like somebody I’d seen before, but somebody different. That was a trip.” As soon as the electricity was turned off, Blackwell’s visualization of Parvizi’s face returned to normal.
Later, Blackwell confirmed that it was only the doctor’s face that changed — his body and hands remained the same.
Though only a single case, the experiment provides strong confirmatory evidence that the fusiform gyrus is indeed directly involved in processing face perception, and that the area is specialized for doing so.
(Source: Los Angeles Times)
"Blue" Light Could Help Teenagers Combat Stress
Adolescents can be chronically sleep deprived because of their inability to fall asleep early in combination with fixed wakeup times on school days. According to the CDC, almost 70 percent of school children get insufficient sleep—less than 8 hours on school nights. This type of restricted sleep schedule has been linked with depression, behavior problems, poor performance at school, drug use, and automobile accidents. A new study from the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute shows that exposure to morning short-wavelength “blue” light has the potential to help sleep-deprived adolescents prepare for the challenges of the day and deal with stress, more so than dim light.
The study was a collaboration between Associate Professor and Director of the LRC Light and Health Program Mariana Figueiro and LRC Director and Professor Mark S. Rea. Results of the study titled “Short-Wavelength Light Enhances Cortisol Awakening Response in Sleep-Restricted Adolescents,” were recently published in the open access International Journal of Endocrinology. The full text is available at http://www.hindawi.com/journals/ije/2012/301935/.
How Does the Brain Process Art?
New imaging techniques are mapping the locations of our aesthetic response
In Michelangelo’s Expulsion from Paradise, a fresco panel on the ceiling of the Sistine Chapel, the fallen-from-grace Adam wards off a sword-wielding angel, his eyes averted from the blade and his wrist bent back defensively. It is a gesture both wretched and beautiful. But what is it that triggers the viewer’s aesthetic response—the sense that we’re right there with him, fending off blows?
Recently, neuroscientists and an art historian asked ten subjects to examine the wrist detail from the painting, and—using a technique called transcranial magnetic stimulation (TMS)—monitored what happened in their brains. The researchers found that the image excited areas in the primary motor cortex that controlled the observers’ own wrists.
“Just the sight of the raised wrist causes an activation of the muscle,” reports David Freedberg, the Columbia University art history professor involved in the study. This connection explains why, for instance, viewers of Degas’ ballerinas sometimes report that they experience the sensation of dancing—the brain mirrors actions depicted on the canvas.
Freedberg’s study is part of the new but growing field of neuroaesthetics, which explores how the brain processes a work of art. The discipline emerged 12 years ago with publication of British neuroscientist Semir Zeki’s book, Inner Vision: An Exploration of Art and the Brain. Today, related studies depend on increasingly sophisticated brain-imaging techniques, including TMS and functional magnetic resonance imaging (fMRI), which maps blood flow and oxygenation in the brain. Scientists might monitor an observer’s reaction to a classical sculpture, then warp the sculpture’s body proportions and observe how the viewer’s response changes. Or they might probe what occurs when the brain contemplates a Chinese landscape painting versus an image of a simple, repetitive task.
Ulrich Kirk, a neuroscientist at the Virginia Tech Carilion Research Institute, is also interested in artworks’ contexts. Would a viewer respond the same way to a masterpiece enshrined in the Louvre if he beheld the same work displayed in a less exalted setting, such as a garage sale? In one experiment, Kirk showed subjects a series ofimages—some, he explained, were fine artwork; others were created by Photoshop. In reality, none were Photoshop-generated; Kirk found that different areas of viewers’ brains fired up when he declared an image to be “art.”
Kirk also hopes one day to plumb the brains of artists themselves. “You might be able to image creativity as it happens, by putting known artists in the fMRI,” he says.
Others, neuroscientists included, worry that neuroscience offers a reductionist perspective. Vilayanur Ramachandran, a neuroscientist at the University of California at San Diego, says that neuroaesthetics undoubtedly “enriches our understanding of human aesthetic experience.” However, he adds, “We have barely scratched the surface…the quintessence of art, and of genius, still eludes us—and may elude us forever.”
(Source: smithsonianmag.com)