Posts tagged neuroscience
Articles and news from the latest research reports.
New MS drug proves effective where others have failed
A drug which ‘reboots’ a person’s immune system has been shown to be an effective treatment for multiple sclerosis (MS) patients who have already failed to respond to the first drug with which they were treated (a ‘first-line’ therapy), as well as affected individuals who were previously untreated. The results of these two phase III clinical trials were published today in the journal The Lancet.
The new studies, sponsored by Genzyme (a Sanofi company) and Bayer Schering Pharma, showed that alemtuzumab significantly reduces the number of attacks (or relapses) experienced by people with MS compared to interferon beta-1a (known commercially as Rebif). This was seen both in patients who had not previously received any treatment (drug-naïve) and those who have continued to show disease activity whilst taking an existing treatment for MS.
High blood pressure damages the brain in early middle age
Uncontrolled high blood pressure damages the brain’s structure and function as early as young middle-age, and even the brains of middle-aged people who clinically would not be considered to have hypertension have evidence of silent structural brain damage, a study led by researchers at UC Davis has found.
The investigation found accelerated brain aging among hypertensive and prehypertensive individuals in their 40s, including damage to the structural integrity of the brain’s white matter and the volume of its gray matter, suggesting that vascular brain injury “develops insidiously over the lifetime with discernible effects.”
The study is the first to demonstrate that there is structural damage to the brains of adults in young middle age as a result of high blood pressure, the authors said. Structural damage to the brain’s white matter caused by high blood pressure previously has been associated with cognitive decline in older individuals.
Published online today in the medical journal The Lancet Neurology, the study will appear in print in the December 2012 issue. It emphasizes the need for lifelong attention to vascular risk factors for brain aging, said study senior author Charles DeCarli, professor of neurology and director of the UC Davis Alzheimer’s Disease Center.
Global Genome Effort Seeks Genetic Roots of Disease
By decoding the genomes of more than 1,000 people whose homelands stretch from Africa and Asia to Europe and the Americas, scientists have compiled the largest and most detailed catalog yet of human genetic variation. The massive resource will help medical researchers find the genetic roots of rare and common diseases in populations worldwide.
The 1000 Genomes Project involved some 200 scientists at Washington University School of Medicine in St. Louis and other institutions. Results detailing the DNA variations of individuals from 14 ethnic groups are published Oct. 31 in the journal Nature. Eventually, the initiative will involve 2,500 individuals from 26 populations.
“With this resource, researchers have a roadmap to search for the genetic origins of diseases in populations around the globe,” says one of the study’s co-principal investigators, Elaine Mardis, PhD, co-director of The Genome Institute at Washington University. “We estimate that each person carries up to several hundred rare DNA variants that could potentially contribute to disease. Now, scientists can investigate how detrimental particular rare variants are in different ethnic groups.”
When people worry about math, the brain feels the pain
Mathematics anxiety can prompt a response in the brain similar to when a person experiences physical pain, according to new research at the University of Chicago.
Using brain scans, scholars determined that the brain areas active when highly math-anxious people prepare to do math overlap with the same brain areas that register the threat of bodily harm—and in some cases, physical pain.
“For someone who has math anxiety, the anticipation of doing math prompts a similar brain reaction as when they experience pain—say, burning one’s hand on a hot stove,” said Sian Beilock, professor of psychology at the University of Chicago and a leading expert on math anxiety.
Surprisingly, the researchers found it was the anticipation of having to do math, and not actually doing math itself, that looked like pain in the brain. “The brain activation does not happen during math performance, suggesting that it is not the math itself that hurts; rather the anticipation of math is painful,” added Ian Lyons, a 2012 PhD graduate in psychology from UChicago and a postdoctoral scholar at Western University in Ontario, Canada.
The two report their findings in a paper, “When Math Hurts: Math Anxiety Predicts Pain Network Activation in Anticipation of Doing Math,” in the current issue of PLOS One.
To bee an art critic, choosing between Picasso and Monet
Honeybees are also discerning art critics, according to scientists from UQ’s Queensland Brain Institute, the UQ School of Psychology and the Federal University of Sao Carlos, Brazil.
The study, published in the Journal of Comparative Physiology A, found honeybees had remarkable visual learning and discrimination abilities that extended beyond simple colours, shapes or patterns.
QBI researcher Dr Judith Reinhard said honeybees had a highly developed capacity for processing complex visual information, and could distinguish landscape scenes, types of flowers, and even human faces.
“This suggests that in spite of their small brain, honeybees have a highly developed capacity for processing complex visual information, comparable in many respects to vertebrates,” she said.
Dr Reinhard and her team investigated whether this capacity extended to complex images that humans distinguish on the basis of artistic style, including Impressionist paintings by Monet and Cubist paintings by Picasso.
“We were able to show that honeybees learned to simultaneously discriminate between five different Monet and Picasso paintings, and that they did not rely on luminance, colour, or spatial frequency information,” she said.
When presented with novel paintings of the same style, the bees demonstrated an ability to generalise, suggesting they could differentiate Monet from Picasso by extracting and learning the characteristic visual information inherent in each style.
“Our study suggests that discrimination of artistic styles is not a higher cognitive function that is unique to humans, but simply due to the capacity of animals – from insects to humans – to extract and categorise the visual characteristics of complex images,” Dr Reinhard said.
Animals, including dogs, dolphins, monkeys and man, follow gaze. What mediates this bias towards the eyes? One hypothesis is that primates possess a distinct neural module that is uniquely tuned for the eyes of others. An alternative explanation is that configural face processing drives fixations to the middle of peoples’ faces, which is where the eyes happen to be located. We distinguish between these two accounts. Observers were presented with images of people, non-human creatures with eyes in the middle of their faces (`humanoids’) or creatures with eyes positioned elsewhere (`monsters’). There was a profound and significant bias towards looking early and often at the eyes of humans and humanoids and also, critically, at the eyes of monsters. These findings demonstrate that the eyes, and not the middle of the head, are being targeted by the oculomotor system.
How does the brain measure time?
(Image: bzztbomb)
Researchers at the University of Minnesota’s Center for Magnetic Resonance Research (CMRR) have found a small population of neurons that is involved in measuring time, which is a process that has traditionally been difficult to study in the lab.
In the study, which is published October 30 in the open access journal PLOS Biology, the researchers developed a task in which monkeys could only rely on their internal sense of the passage of time. Their task design eliminated all external cues which could have served as “clocks”.
The monkeys were trained to move their eyes consistently at regular time intervals without any external cues or immediate expectation of reward. Researchers found that despite the lack of sensory information, the monkeys were remarkably precise and consistent in their timed behaviors. This consistency could be explained by activity in a specific region of the brain called the lateral intraparietal area (LIP). Interestingly, the researchers found that LIP activity during their task was different from activity in previous studies that had failed to eliminate external cues or expectation of reward.
"In contrast to previous studies that observed a build-up of activity associated with the passage of time, we found that LIP activity decreased at a constant rate between timed movements," said lead researcher Geoffrey Ghose, Ph.D., associate professor of neuroscience at the University of Minnesota. "Importantly, the animals’ timing varied after these neurons were more, or less, active. It’s as if the activity of these neurons was serving as an internal hourglass."
By developing a model to help explain the differences in timing signals they see relative to previous studies, their study also suggests that there is no “central clock” in the brain that is relied upon for all tasks involving timing. Instead, it appears as though each of the brain’s circuits responsible for different actions are capable of independently producing an accurate timing signal.
One important direction for future research is to explore how such precise timing signals arise as a consequence of practice and learning, and whether, when the signals are altered, there are clear effects on behavior.
(Source: medicalxpress.com)
Empathy represses analytic thought, and vice versa
New research shows a simple reason why even the most intelligent, complex brains can be taken by a swindler’s story – one that upon a second look offers clues it was false.
When the brain fires up the network of neurons that allows us to empathize, it suppresses the network used for analysis, a pivotal study led by a Case Western Reserve University researcher shows.
How could a CEO be so blind to the public relations fiasco his cost-cutting decision has made?
When the analytic network is engaged, our ability to appreciate the human cost of our action is repressed.
At rest, our brains cycle between the social and analytical networks. But when presented with a task, healthy adults engage the appropriate neural pathway, the researchers found.
The study shows for the first time that we have a built-in neural constraint on our ability to be both empathetic and analytic at the same time
The work suggests that established theories about two competing networks within the brain must be revised. More, it provides insights into the operation of a healthy mind versus those of the mentally ill or developmentally disabled.
“This is the cognitive structure we’ve evolved,” said Anthony Jack, an assistant professor of cognitive science at Case Western Reserve and lead author of the new study. “Empathetic and analytic thinking are, at least to some extent, mutually exclusive in the brain.”
The research is published in the current online issue of NeuroImage.