Rogalski’s new study has for the first time identified an elite group of elderly people age 80 and older whose memories are as sharp as people 20 to 30 years younger than them. And on 3-D MRI scans, the SuperAger participants’ brains appear as young — and one brain region was even bigger — than the brains of the middle-aged participants.
She was astounded by the vitality of the SuperAgers’ cortex — the outer layer of the brain important for memory, attention and other thinking abilities. Theirs was much thicker than the cortex of the normal group of elderly 80 and older (whose showed significant thinning) and closely resembled the cortex size of participants ages 50 to 65, considered the middle-aged group of the study.
"These findings are remarkable given the fact that grey matter or brain cell loss is a common part of normal aging," said Rogalski, the principal investigator of the study and an assistant research professor at the Cognitive Neurology and Alzheimer’s Disease Center at Northwestern University Feinberg School of Medicine.
Rogalski is senior author of the paper, which is published in the Journal of the International Neuropsychological Society.
Filed under science neuroscience brain psychology memory elderly
By: Richard C. Lewis | 2012.08.16
Everyone knows the adage: “If something sounds too good to be true, then it probably is.” So, why, then, do some people fall for scams and why are older folks especially prone to being duped?
An answer, it seems, is because a specific area of the brain has deteriorated or is damaged, according to researchers at the University of Iowa. By examining patients with various forms of brain damage, the researchers report they’ve pinpointed the precise location in the human brain, called the ventromedial prefrontal cortex, that controls belief and doubt, and which explains why some of us are more gullible than others.
Patients with damage to the ventromedial prefrontal cortex were roughly twice as likely to believe a given ad, even when given disclaimer information pointing out it was misleading. And, they were more likely to buy the item, regardless of whether misleading information had been corrected. Photo by Bill Adams.
“The current study provides the first direct evidence beyond anecdotal reports that damage to the vmPFC (ventromedial prefrontal cortex) increases credulity. Indeed, this specific deficit may explain why highly intelligent vmPFC patients can fall victim to seemingly obvious fraud schemes,” the researchers wrote in the paper published in a special issue of the journal Frontiers in Neuroscience.
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Filed under science elderly brain psychology neuroscience ventromedial prefrontal cortex
16 August 2012
Ten out of 11 patients with severe Tourette’s Syndrome have reported improvement after receiving deep brain stimulation surgery, according to University of New South Wales research published in the American Journal of Psychiatry.
Tourette’s Syndrome is a neurological disorder characterised by repetitive involuntary movements and vocalisations called tics and can also include behavioural difficulties.
Deep brain stimulation is a therapeutic technique that involves placing electrodes at specific sites in the brain to deliver continuous stimulation from an implanted generator.
Study leader, UNSW Scientia Professor Perminder Sachdev, says deep brain stimulation may have an important role in treating Tourette’s Syndrome in its most severe form. He says tics are generally treated with medications that work well in about 50 to 70 per cent of cases. Drugs, however, can have side effects in some patients.
Eleven patients, eight of them in their late thirties with severe Tourette’s Syndrome, underwent deep brain stimulation at St Andrew’s Hospital in Brisbane - under the care of neurologist Professor Peter Silburn and neurosurgeon Associate Professor Terry Coyne - as part of the study. They were followed up initially one month after surgery and then around a year after the procedure.
Ten out of the 11 patients involved in the joint UNSW Medicine and Asia-Pacific Centre for Neuromodulation study reported immediate improvement in tic severity soon after the treatment, with an overall 48 per cent reduction in monitor tics and a 57 per cent reduction in phonic tics at final follow-up. Associated psychiatric symptoms also improved.
“Because deep brain stimulation involves brain surgery, it has some risks, even though these are low. It is therefore only likely to be used in individuals who are significantly affected by their tics,” Scientia Professor Sachdev says.
“Our study demonstrates that when suitably selected, patients can benefit greatly from deep brain stimulation.”
Source: University of New South Wales
Filed under science brain psychology neuroscience deep brain stimulation tourette syndrome
Researchers have developed a system that allows the soft robots to either camouflage themselves against a background, or to make bold color displays. Such a “dynamic coloration” system could one day have a host of uses, ranging from helping doctors plan complex surgeries to acting as a visual marker to help search crews following a disaster, said Stephen Morin, a Post-Doctoral Fellow in Chemistry and Chemical Biology and first author of the paper.
"When we began working on soft robots, we were inspired by soft organisms, including octopi and squid," Morin said. "One of the fascinating characteristics of these animals is their ability to control their appearance, and that inspired us to take this idea further and explore dynamic coloration. I think the important thing we’ve shown in this paper is that even when using simple systems – in this case we have simple, open-ended micro-channels – you can achieve a great deal in terms of your ability to camouflage an object, or to display where an object is."
"One of the most interesting questions in science is ‘Why do animals have the shape, and color, and capabilities that they do?’" said Whitesides. "Evolution might lead to a particular form, but why? One function of our work on robotics is to give us, and others interested in this kind of question, systems that we can use to test ideas. Here the question might be: ‘How does a small crawling organism most efficiently disguise (or advertise) itself in leaves?’ These robots are test-beds for ideas about form and color and movement."
Filed under science neuroscience robotics camouflage soft robots
TAU research says genetics can reveal your geographic ancestral origin
While your DNA is unique, it also tells the tale of your family line. It carries the genetic history of your ancestors down through the generations. Now, says a Tel Aviv University researcher, it’s also possible to use it as a map to your family’s past.
Prof. Eran Halperin of TAU’s Blavatnik School of Computer Science and Department of Molecular Microbiology and Biotechnology, along with a group of researchers from University of California, Los Angeles, are giving new meaning to the term “genetic mapping.” Using a probabilistic model of genetic traits for every coordinate on the globe, the researchers have developed a method for determining more precisely the geographical location of a person’s ancestral origins.
The new method is able to pinpoint more specific locations for an individual’s ancestors, for example placing an individual’s father in Paris and mother in Barcelona. Previous methods would “split the difference” and place this origin inaccurately at a site between those two cities, such as Lyon.
Published in the journal Nature Genetics, this method has the potential to reveal the ancestry, origins, and migration patterns of many different human and animal populations. It could also be a new model for learning about the genome.
Points of origin
There are points in the human genome called SNPs that are manifested differently in each individual, explains Prof. Halperin. These points mutated sometime in the past and the mutation was then passed to a large part of the population in a particular geographic region. The probability of a person possessing these mutations today varies depending on the geographical location of those early ancestors.
"We wanted to ask, for example, about the probability of having the genetic mutation ‘A’ in a particular position on the genome based on geographical coordinates," he says. When you look at many of these positions together in a bigger picture, it’s possible to group populations with the same mutation by point of origin.
To test their method, Prof. Halperin and his fellow researchers studied DNA samples from 1,157 people from across Europe. Using a probabilistic mathematical algorithm based on mutations in the genome, they were able to accurately determine their ancestral point or points of origin using only DNA data and the new mathematical model, unravelling genetic information to ascertain two separate points on the map for the mother and father. The researchers hope to extend this model to identify the origins of grandparents, great-grandparents, and so on.
The new method could provide information that has applications in population genetic studies — to study a disease that impacts a particular group, for example. Researchers can track changes in different genomic traits across a map, such as the tendency for southern Europeans to have a mutation in a gene that causes lactose intolerance, a mutation missing from that gene in northern Europeans.
A closer look at migration
The researchers believe that their model could have also relevance for the animal kingdom, tracking the movement of animal populations. “In principle, you could figure out where the animals have migrated from, and as a result learn about habitat changes due to historical climate change or other factors,” says Prof. Halperin.
Source: Tel Aviv University
Filed under science neuroscience genetics DNA genetic mapping
DNA: The Ultimate Hard Drive
When it comes to storing information, hard drives don’t hold a candle to DNA. Our genetic code packs billions of gigabytes into a single gram. A mere milligram of the molecule could encode the complete text of every book in the Library of Congress and have plenty of room to spare. All of this has been mostly theoretical—until now. In a new study, researchers stored an entire genetics textbook in less than a picogram of DNA—one trillionth of a gram—an advance that could revolutionize our ability to save data.
A few teams have tried to write data into the genomes of living cells. But the approach has a couple of disadvantages. First, cells die—not a good way to lose your term paper. They also replicate, introducing new mutations over time that can change the data.
To get around these problems, a team led by George Church, a synthetic biologist at Harvard Medical School in Boston, created a DNA information-archiving system that uses no cells at all. Instead, an inkjet printer embeds short fragments of chemically synthesized DNA onto the surface of a tiny glass chip. To encode a digital file, researchers divide it into tiny blocks of data and convert these data not into the 1s and 0s of typical digital storage media, but rather into DNA’s four-letter alphabet of As, Cs, Gs, and Ts. Each DNA fragment also contains a digital “barcode” that records its location in the original file. Reading the data requires a DNA sequencer and a computer to reassemble all of the fragments in order and convert them back into digital format. The computer also corrects for errors; each block of data is replicated thousands of times so that any chance glitch can be identified and fixed by comparing it to the other copies.
To demonstrate its system in action, the team used the DNA chips to encode a genetics book co-authored by Church. It worked. After converting the book into DNA and translating it back into digital form, the team’s system had a raw error rate of only two errors per million bits, amounting to a few single-letter typos. That is on par with DVDs and far better than magnetic hard drives. And because of their tiny size, DNA chips are now the storage medium with the highest known information density, the researchers report online today in Science.
Don’t replace your flash drive with genetic material just yet, however. The cost of the DNA sequencer and other instruments “currently makes this impractical for general use,” says Daniel Gibson, a synthetic biologist at the J. Craig Venter Institute in Rockville, Maryland, “but the field is moving fast and the technology will soon be cheaper, faster, and smaller.” Gibson led the team that created the first completely synthetic genome, which included a “watermark” of extra data encoded into the DNA. The researchers used a three-letter coding system that is less efficient than the Church team’s but has built-in safeguards to prevent living cells from translating the DNA into proteins. “If DNA is going to be used for this purpose, and outside a laboratory setting, then you would want to use DNA sequence that is least likely to be expressed in the environment,” he says. Church disagrees. Unless someone deliberately “subverts” his DNA data-archiving system, he sees little danger.
Filed under science biology genetics DNA neuroscience genomics
The PLOS ONE Synthetic Biology Collection: Six Years and Counting
Since it was launched in 2006, PLOS ONE has published over fifty articles illustrating the many facets of the emerging field of synthetic biology. This article reviews these publications by organizing them into broad categories focused on DNA synthesis and assembly techniques, the development of libraries of biological parts, the use of synthetic biology in protein engineering applications, and the engineering of gene regulatory networks and metabolic pathways. Finally, we review articles that describe enabling technologies such as software and modeling, along with new instrumentation. In order to increase the visibility of this body of work, the papers have been assembled into the PLOS ONE Synthetic Biology Collection (www.ploscollections.org/synbio). Many of the innovative features of the PLOS ONE web site will help make this collection a resource that will support a lively dialogue between readers and authors of PLOS ONE synthetic biology papers. The content of the collection will be updated periodically by including relevant articles as they are published by the journal. Thus, we hope that this collection will continue to meet the publishing needs of the synthetic biology community.
Filed under science biology synthetic biology articles plos one
A pair of 90-day-old cow fetuses clearly visible inside an amniotic sac, 1965. (Image: Fritz Goro—Time & Life Pictures/Getty Images)
If science seeks to uncover the truth, then photography seeks to lay that truth bare to the world. Photographer Fritz Goro understood this sentiment well. His photographs highlight the beautiful, strange, amusing and poignant within the realm of scientific inquiry. Goro spent four decades as a photographer for LIFE magazine and Scientific American.
(Source: Wired)
Filed under science photography Fritz Goro photographers
The vast majority of people with addiction have suffered significant previous trauma, and many people who struggle with addiction suffer from post-traumatic stress disorder (PTSD) simultaneously. But the treatment of these patients has posed a conundrum: experts have believed that PTSD treatment should not begin until the addicted person achieves lasting abstinence, because of the risk that PTSD treatment may trigger relapse, yet addicted people with untreated PTSD are rarely able to abstain for long.
Now, a new study suggests that there may be no need to wait. Researchers found that using exposure therapy — the gold-standard treatment for PTSD, which involves exposure to memories and reminders of patients’ past trauma — can successfully reduce symptoms of PTSD, even when people with addiction continue to use drugs. And, although exposure therapy requires patients to face some of their worst fears, it does not increase their drug use or prompt them to drop out of treatment more than ordinary addiction therapy, the study found.
“The exciting thing in my view is that [the study] supports people with drug and alcohol problems having access to other forms of psychological interventions, rather than being fobbed off and told to sort out their alcohol or drug problem first,” says Michael Farrell, director of the National Drug and Alcohol Research Center at the University of New South Wales in Sydney, Australia, where the research was conducted.
The finding could potentially help the majority of those who suffer from addiction or PTSD: one-half to two-thirds of people with addictions suffer from PTSD concurrently, or have in the past, and about the same proportion of people with PTSD also have substance use disorders.
The new study involved 103 people with both conditions. Most were addicted to multiple drugs, primarily heroin, marijuana and alcohol. More than two-thirds of the participants had been traumatized during childhood, with almost half reporting a history of sexual abuse.
Researchers randomly assigned half of the participants to simply continue the addiction treatment of their choice, whether it was detoxification leading to abstinence, residential treatment or maintenance on medications like methadone and buprenorphine (Suboxone, Subutex).
The other half received their usual treatment, plus exposure therapy for PTSD, which consisted of 13 one-on-one sessions with a clinical psychologist, meeting about once a week for 90 minutes at a time. The therapy began with education about PTSD and addiction, including instruction on cognitive techniques to address distressing thoughts that could lead to relapse. Then, when patients were ready, they were exposed to reminders of their traumatic experience, which they usually avoided out of fear of triggering flashbacks and intense anxiety. Exposure therapy works to reduce or eliminate these PTSD symptoms by breaking patients’ cycle of fear and avoidance.
Indeed, participants in the exposure treatment “demonstrated significantly greater reductions in PTSD symptom severity compared with participants randomized to receive usual treatment alone,” the authors wrote. However, drug use in the exposure therapy group didn’t decline any more than it did in the usual treatment group. Both groups saw a reduction in the severity of addiction but in each case, the majority of participants continued to use drugs. Notably, however, drug use did not increase due to exposure therapy.
“These findings challenge the widely held view that patients need to be abstinent before any trauma work, let alone prolonged exposure therapy, is commenced,” the authors wrote. “[F]indings from the present study demonstrate that abstinence is not required.”
Importantly, however, while the findings showed that carefully delivered exposure therapy can help, they did not support the practice of forcing addicts to confront trauma in settings where they do not feel safe or in control. Exposure therapy is calibrated so that patients do not become overwhelmed or feel helpless; in contrast, coercion by the therapist can re-traumatize patients and worsen both PTSD and addiction symptoms, previous studies have shown.
In other words, it’s not clear that treating people with addiction by compelling them to recall or re-enact traumatic experiences — a commonly used tactic in group settings — actually helps. What the current study shows is that when trained clinical psychologists carefully deliver exposure therapy in a tightly monitored trial, they can help ease PTSD symptoms in people with addiction.
By Maia Szalavitz | August 15, 2012
Source: TIME
Filed under science neuroscience brain psychology PTSD addiction treatment
