Posts tagged neuroscience
Articles and news from the latest research reports.
![Scientists have found that one gene is responsible for variability in locomotion in horses and mice.
Traits such as height are controlled by the interaction of up to 700 genes. So it came as quite a shock to researchers from Uppsala University (UU) and their international collaborators that the mutation of just a single gene is responsible for variability in locomotion in horses and mice. Furthermore, the research team discovered that this gene, DMRT3, is expressed in a previously unknown set of neurons in the spinal cord. These findings provide insight into the neural circuits that coordinate movement in vertebrates.
“The amazing result was that we found one very strong signal on one chromosome which by further work led to the discovery of the DMRT3 mutation,” explains Leif Andersson, co-author of the paper published in Nature, from UU and Swedish University of Agricultural Sciences. “This was unexpected since we had [anticipated] a much more complex genetic background for a trait like this.”](http://33.media.tumblr.com/tumblr_ma13qp01ib1rog5d1o1_500.gif)
Scientists have found that one gene is responsible for variability in locomotion in horses and mice.
Traits such as height are controlled by the interaction of up to 700 genes. So it came as quite a shock to researchers from Uppsala University (UU) and their international collaborators that the mutation of just a single gene is responsible for variability in locomotion in horses and mice. Furthermore, the research team discovered that this gene, DMRT3, is expressed in a previously unknown set of neurons in the spinal cord. These findings provide insight into the neural circuits that coordinate movement in vertebrates.
“The amazing result was that we found one very strong signal on one chromosome which by further work led to the discovery of the DMRT3 mutation,” explains Leif Andersson, co-author of the paper published in Nature, from UU and Swedish University of Agricultural Sciences. “This was unexpected since we had [anticipated] a much more complex genetic background for a trait like this.”
Half a dozen times each night, your slumbering body performs a remarkable feat of coordination.
During the deepest throes of sleep, the body’s support systems run on their own timetables. Nerve cells hum along in your brain, their chitchat generating slow waves that signal sleep’s nether stages. Yet, like buses and trains with overlapping routes but unsynchronized schedules, this neural conversation has little to say to your heart, which pumps blood to its own rhythm through the body’s arteries and veins. Air likewise skips into the nostrils and down the windpipe in seemingly random spits and spats. And muscle fluctuations that make the legs twitch come and go as if in a vacuum. Networks of muscles, of brain cells, of airways and lungs, of heart and vessels operate largely independently.
Every couple of hours, though, in as little as 30 seconds, the barriers break down. Suddenly, there’s synchrony. All the disjointed activity of deep sleep starts to connect with its surroundings. Each network — run via the group effort of its own muscular, cellular and molecular players — joins the larger team.
This change, marking the transition from deep to light sleep, has only recently been understood in detail — thanks to a new look at when and how the body’s myriad networks link up to form an übernetwork.
Alzheimer’s Experts Provide Strategic Roadmap
This week, a strategic roadmap to help to the nation’s health care system cope with the impending public health crisis caused Alzheimer’s disease and related dementia will be published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association. The plan aims to link the latest scientific findings with clinical care and bring together patients, families, scientists, pharmaceutical companies, regulatory agencies, and advocacy organizations behind a common set of prioritized goals. The consensus document is the outcome of a June meeting of leading Alzheimer’s researchers, advocates and clinicians, who gathered as part of the Marian S. Ware Alzheimer Program at the University of Pennsylvania.
Today, 5.4 million people are living with the disease, and more than 15 million Americans are caring for persons with Alzheimer’s and other dementias, according to the Alzheimer’s Association. Alzheimer’s disease is the sixth-leading cause of death in the United States and the only cause of death among the top 10 in the United States that cannot be prevented, cured, or even slowed.
"Our plan aims to provide good quality care for affected patients and families, advance our understanding of the pathophysiology and natural history of AD and other dementias, develop effective treatments to slow or prevent these diseases, and translate scientific advances successfully into policy and practice," the authors wrote.
(Source: nursing.upenn.edu)
Study finds new benefit of coffee: It reduces pain
The surprising finding is based on a study involving 48 volunteers who agreed to spend 90 minutes performing fake computer tasks meant to mimic office work. The tasks were known to cause pain in the shoulders, neck, forearms and wrists, and the researchers wanted to compare how people with chronic pain and those who were pain-free tolerated the tasks.
As a matter of convenience, the scientists allowed people to drink coffee before taking the test “to avoid unpleasant effects of caffeine deprivation, e.g. decreased vigor and alertness, sleepiness, and fatigue,” they reported.
But when it came time to analyze the data, the researchers from Norway’s National Institute of Occupational Health and Oslo University Hospital noticed that the 19 people who drank coffee reported a lower intensity of pain than the 29 people who didn’t.
In the shoulders and neck, for instance, the average pain intensity was rated 41 (on a 100-point scale) among the coffee drinkers and 55 for the coffee abstainers. Similar gaps were found for all pain sites measured, and coffee’s apparent pain-mitigation effect held up regardless of whether the subjects had chronic pain or not.
The authors of the study, which was published this week in the journal BMC Research Notes, cautioned that since the study wasn’t designed to test coffee’s influence on pain, the results come with many uncertainties. For starters, the researchers don’t know how much coffee the coffee drinkers consumed before taking the computer tests. They also doubt that the coffee drinkers and abstainers were similar in all respects except for their java consumption. Problems like these tend to undermine the importance of the findings. But those reservations are unlikely to trouble the legions of coffee drinkers looking for any reason not to cut back on their daily caffeine habit.
Have you ever noticed how tiresome it can be to follow a conversation at a noisy party? Rest assured: this is not necessarily due to bad hearing – although that might make things worse. Scientists at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig have found that adverse listening situations are difficult for the brain, partly because they draw on the same, limited resources supporting our short-term memory. The new findings are particularly relevant to understanding the cognitive consequences of hearing damage, a condition that affects an increasing number of people.
Brain Networks of Explicit and Implicit Learning
Are explicit versus implicit learning mechanisms reflected in the brain as distinct neural structures, as previous research indicates, or are they distinguished by brain networks that involve overlapping systems with differential connectivity? In this functional MRI study we examined the neural correlates of explicit and implicit learning of artificial grammar sequences. Using effective connectivity analyses we found that brain networks of different connectivity underlie the two types of learning: while both processes involve activation in a set of cortical and subcortical structures, explicit learners engage a network that uses the insula as a key mediator whereas implicit learners evoke a direct frontal-striatal network. Individual differences in working memory also differentially impact the two types of sequence learning.
Children get their sense of humour from their parents as a study has found babies as young as six months learn to laugh at the same thing as their mothers and fathers.
Master gene affects neurons that govern breathing at birth and adulthood
When mice are born lacking the master gene Atoh1, none breathe well and all die in the newborn period. Why and how this occurs could provide new answers about sudden infant death syndrome (SIDS), but the solution has remained elusive until now.
Research led by Baylor College of Medicine and the Jan and Dan Duncan Neurological Research Institute at Texas Children’s Hospital demonstrates that when the gene is lacking in a special population of neurons called RTN (retrotrapezoid nucleus), roughly half the young mice die at birth. Those who survive are less likely to respond to excess levels of carbon dioxide as adults. A report of their work appears online in the journal Neuron.
"The death of mice at birth clued us in that Atoh1 must be needed for the function of some neurons critical for neonatal breathing, so we set out to define these neurons," said Dr. Huda Zoghbi, senior author of the report and director of the Neurological Research Institute and a professor of molecular and human genetics, neuroscience, neurology and pediatrics at BCM. Zoghbi is also a Howard Hughes Medical Institute investigator.
"We took a genetic approach to find the critical neurons," said Wei-Hsiang Huang, a graduate student in the Program in Developmental Biology at BCM who works in Zoghbi’s laboratory. With careful studies to "knockout" the activity of the gene in a narrower and narrower area in the brain, they slowly eliminated possible neurons to determine that loss of Atoh1 in the RTN neurons was the source of the problem.
"Discovering that Atoh1 is indeed critical for the RTN neurons to take their right place in the brainstem and connect with the breathing center helped us uncover why they are important for neonatal breathing," said Zoghbi.
"This population of neurons resides in the ventral brainstem," said Huang. "When there is a change in the makeup of the blood (lack of oxygen or buildup of carbon dioxide), the RTN neurons sense that and tell the body to change the way it breathes." A defect in these neurons can disrupt this response.
"Without Atoh1 the mice have significant breathing problems because they do not automatically adjust their breathing to decrease carbon dioxide and oxygenate the blood," he said.
It turns out the findings from this mouse study are relevant to human studies.
"A paper just published reports that developmental abnormalities in the RTN neurons of children with sudden infant death syndrome or sudden unexplained intrauterine death may be linked to altered ventilatory response to carbon dioxide", said Huang (Lavezzi, A.M., et al., Developmental alterations of the respiratory human retrotrapezoid nucleus in sudden unexplained fetal and infant death, Auton. Neurosci. (2012), doi:10.1016/j.autneu.2012.06.005).
(Source: bcm.edu)
Previously existing ideas on how advanced maternal age affects adult health of children have to be reconsidered. It had been thought that mothers delivering later in life have children that are less healthy as adults, because the body of the mother had already degenerated due to physiological effects like decreasing oocyte quality or a weakened placenta. In fact, what affects the health of the grown-up children is not the age of their mother but her education and the number of years she survives after giving birth and thus spends with her offspring. This is the conclusion of a new study by Mikko Myrskylä from the Max Planck Institute for Demographic Research in Rostock, Germany carried out with data from 18,000 US children and their mothers.
Researchers use characteristic differences in eye movements to identify patients with deficits in neurological function.
Observing patients’ eye movements may hold clues about neurological functioning. In a study published last month (August 25) in the Journal of Neurology, scientists show that subtle differences in eye movement patterns can be utilized to identify patients with Parkinson’s, fetal alcohol syndrome, or attention deficit disorder, providing hope for a quick and noninvasive strategy to aid in diagnosing these, and possibly other, neurological diseases.
“I am very impressed with the use of this eye tracking as a potential behavioral biomarker,” said Edward Riley, who studies fetal alcohol syndrome at San Diego State University, but did not participate in the research. The strategy could one day be used to rapidly screen children at risk for behavioral problems, he added, but whose mild symptoms may cause their issues to be overlooked.