Green tea extract boosts your brain power, especially the working memory, new research shows

Green tea is said to have many putative positive effects on health. Now, researchers at the University of Basel are reporting first evidence that green tea extract enhances the cognitive functions, in particular the working memory. The Swiss findings suggest promising clinical implications for the treatment of cognitive impairments in psychiatric disorders such as dementia. The academic journal Psychopharmacology has published their results.In the past the main ingredients of green tea have been thoroughly studied in cancer research. Recently, scientists have also been inquiring into the beverage’s positive impact on the human brain. Different studies were able to link green tea to beneficial effects on the cognitive performance. However, the neural mechanisms underlying this cognitive enhancing effect of green tea remained unknown.Better memoryIn a new study, the researcher teams of Prof. Christoph Beglinger from the University Hospital of Basel and Prof. Stefan Borgwardt from the Psychiatric University Clinics found that green tea extract increases the brain’s effective connectivity, meaning the causal influence that one brain area exerts over another. This effect on connectivity also led to improvement in actual cognitive performance: Subjects tested significantly better for working memory tasks after the admission of green tea extract.For the study healthy male volunteers received a soft drink containing several grams of green tea extract before they solved working memory tasks. …

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MRI reveals genetic activity: Deciphering genes’ roles in learning and memory

Doctors commonly use magnetic resonance imaging (MRI) to diagnose tumors, damage from stroke, and many other medical conditions. Neuroscientists also rely on it as a research tool for identifying parts of the brain that carry out different cognitive functions.Now, a team of biological engineers at MIT is trying to adapt MRI to a much smaller scale, allowing researchers to visualize gene activity inside the brains of living animals. Tracking these genes with MRI would enable scientists to learn more about how the genes control processes such as forming memories and learning new skills, says Alan Jasanoff, an MIT associate professor of biological engineering and leader of the research team.”The dream of molecular imaging is to provide information about the biology of intact organisms, at the molecule level,” says Jasanoff, who is also an associate member of MIT’s McGovern Institute for Brain Research. “The goal is to not have to chop up the brain, but instead to actually see things that are happening inside.”To help reach that goal, Jasanoff and colleagues have developed a new way to image a “reporter gene” — an artificial gene that turns on or off to signal events in the body, much like an indicator light on a car’s dashboard. In the new study, the reporter gene encodes an enzyme that interacts with a magnetic contrast agent injected into the brain, making the agent visible with MRI. This approach, described in a recent issue of the journal Chemical Biology, allows researchers to determine when and where that reporter gene is turned on.An on/off switchMRI uses magnetic fields and radio waves that interact with protons in the body to produce detailed images of the body’s interior. In brain studies, neuroscientists commonly use functional MRI to measure blood flow, which reveals which parts of the brain are active during a particular task. When scanning other organs, doctors sometimes use magnetic “contrast agents” to boost the visibility of certain tissues.The new MIT approach includes a contrast agent called a manganese porphyrin and the new reporter gene, which codes for a genetically engineered enzyme that alters the electric charge on the contrast agent. Jasanoff and colleagues designed the contrast agent so that it is soluble in water and readily eliminated from the body, making it difficult to detect by MRI. However, when the engineered enzyme, known as SEAP, slices phosphate molecules from the manganese porphyrin, the contrast agent becomes insoluble and starts to accumulate in brain tissues, allowing it to be seen.The natural version of SEAP is found in the placenta, but not in other tissues. …

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U.S. headache sufferers get $1 billion worth of brain scans each year

One in eight visits to a a doctor for a headache or migraine end up with the patient going for a brain scan, at a total cost of about $1 billion a year, a new University of Michigan Medical School study finds.And many of those MRI and CT scans — and costs — are probably unnecessary, given the very low odds that serious issues lurk in the patients’ brains.In fact, several national guidelines for doctors specifically discourage scanning the brains of patients who complain of headache and migraine. But the new study shows the rate of brain scans for headache has risen, not fallen, since guidelines for doctors came out. This may mean that patient demand for scans drives much of the cost.The researchers suggest that better education of the public, and insurance plan designs that ask patients to pay part of the cost based on the likely value of the scan for them, may be needed to reduce unnecessary use and spending.The research, published in JAMA Internal Medicine by a team from the U-M Department of Neurology, uses national data on headache-related doctor visits and neuroimaging scans by people over age 18, and calculates estimated total costs across multiple years.In all, 51.1 million headache-related patient visits occurred between 2007 and 2010 — nearly half of them related to migraine. The vast majority were by people under the age of 65, and more than three-quarters of the patients were women. In those same four years, 12.4 percent of these visits resulted in a brain MRI or CT.The researchers estimated the total cost of the four years’ worth of scans at $3.9 billion, based on typical Medicare payments to doctors for imaging.”This is a conservative cost estimate based on what Medicare would pay for these tests. CTs and MRIs are commonly ordered for headache and migraine, and increasing over time, despite the fact that there are rare circumstances where imaging should be used,” says Brian Callaghan, M.D., M.S., the U-M neurologist who led the team performing the study.”Lots of guidelines say we shouldn’t do this — including ones from neurology and radiology groups — but yet we still do it a lot. This is a source of tremendous cost in health care without a lot of evidence to justify the cost,” he notes.A billion dollars’ worth of reassurance?Doctors might order a CT or MRI scan for a headache or migraine to put patients’ minds at ease about fears that a malignant brain tumor, aneurysm, arteriovenous malformation or other issue might be causing their symptoms.And even if the patient doesn’t meet the conditions that guidelines say can benefit most from brain imaging — for instance, someone with an abnormal neurological exam or a known cancer — doctors might order a scan at a patient’s request to protect themselves legally.But past research shows that only 1 percent to 3 percent of scans of patients with repeated headaches find that a growth or blood vessel problem in the brain is to blame. And many of the issues that scans spot turn out not to pose a serious threat — or may not require treatment right away.”There’s solid research showing that the number of times you find serious issues on these scans in headache patients is about the same as that for a randomly chosen group of non-headache patients,” he says. “And a lot of the things we find on such scans aren’t necessarily something we will do something about.”Callaghan notes that the current study, based on data from the Centers for Disease Control & Prevention’s National Ambulatory Care Medical Survey, couldn’t detect which scans met guidelines and which didn’t.But the fact that 14.7 percent of people who saw a doctor for headache or migraine in 2010 went on to have a brain scan would not be expected if guidelines were being followed, he says. The team is working on further research into the appropriateness of the scans ordered for patients.He also notes that the $1 billion a year estimate doesn’t include other costs, including follow-up tests and any treatment that might be ordered if a scan finds something. …

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The musical brain: Novel study of jazz players shows common brain circuitry processes both music, language

The brains of jazz musicians engrossed in spontaneous, improvisational musical conversation showed robust activation of brain areas traditionally associated with spoken language and syntax, which are used to interpret the structure of phrases and sentences. But this musical conversation shut down brain areas linked to semantics — those that process the meaning of spoken language, according to results of a study by Johns Hopkins researchers.The study used functional magnetic resonance imaging (fMRI) to track the brain activity of jazz musicians in the act of “trading fours,” a process in which musicians participate in spontaneous back and forth instrumental exchanges, usually four bars in duration. The musicians introduce new melodies in response to each other’s musical ideas, elaborating and modifying them over the course of a performance.The results of the study suggest that the brain regions that process syntax aren’t limited to spoken language, according to Charles Limb, M.D., an associate professor in the Department of Otolaryngology-Head and Neck Surgery at the Johns Hopkins University School of Medicine. Rather, he says, the brain uses the syntactic areas to process communication in general, whether through language or through music.Limb, who is himself a musician and holds a faculty appointment at the Peabody Conservatory, says the work sheds important new light on the complex relationship between music and language.”Until now, studies of how the brain processes auditory communication between two individuals have been done only in the context of spoken language,” says Limb, the senior author of a report on the work that appears online Feb. 19 in the journal PLOS ONE. “But looking at jazz lets us investigate the neurological basis of interactive, musical communication as it occurs outside of spoken language.”We’ve shown in this study that there is a fundamental difference between how meaning is processed by the brain for music and language. Specifically, it’s syntactic and not semantic processing that is key to this type of musical communication. Meanwhile, conventional notions of semantics may not apply to musical processing by the brain.”To study the response of the brain to improvisational musical conversation between musicians, the Johns Hopkins researchers recruited 11 men aged 25 to 56 who were highly proficient in jazz piano performance. During each 10-minute session of trading fours, one musician lay on his back inside the MRI machine with a plastic piano keyboard resting on his lap while his legs were elevated with a cushion. A pair of mirrors was placed so the musician could look directly up while in the MRI machine and see the placement of his fingers on the keyboard. …

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Brain’s ‘sweet spot’ for love found in neurological patient

A region deep inside the brain controls how quickly people make decisions about love, according to new research at the University of Chicago.The finding, made in an examination of a 48-year-old man who suffered a stroke, provides the first causal clinical evidence that an area of the brain called the anterior insula “plays an instrumental role in love,” said UChicago neuroscientist Stephanie Cacioppo, lead author of the study.In an earlier paper that analyzed research on the topic, Cacioppo and colleagues defined love as “an intentional state for intense [and long-term] longing for union with another” while lust, or sexual desire, is characterized by an intentional state for a short-term, pleasurable goal.In this study, the patient made decisions normally about lust but showed slower reaction times when making decisions about love, in contrast to neurologically typical participants matched on age, gender and ethnicity. The findings are presented in a paper, “Selective Decision-Making Deficit in Love Following Damage to the Anterior Insula,” published in the journal Current Trends in Neurology.”This distinction has been interpreted to mean that desire is a relatively concrete representation of sensory experiences, while love is a more abstract representation of those experiences,” said Cacioppo, a research associate and assistant professor in psychology. The new data suggest that the posterior insula, which affects sensation and motor control, is implicated in feelings of lust or desire, while the anterior insula has a role in the more abstract representations involved in love.In the earlier paper, “The Common Neural Bases Between Sexual Desire and Love: A Multilevel Kernel Density fMRI Analysis,” Cacioppo and colleagues examined a number of studies of brain scans that looked at differences between love and lust.The studies showed consistently that the anterior insula was associated with love, and the posterior insula was associated with lust. However, as in all fMRI studies, the findings were correlational.”We reasoned that if the anterior insula was the origin of the love response, we would find evidence for that in brain scans of someone whose anterior insula was damaged,” she said.In the study, researchers examined a 48-year-old heterosexual male in Argentina, who had suffered a stroke that damaged the function of his anterior insula. He was matched with a control group of seven Argentinian heterosexual men of the same age who had healthy anterior insula.The patient and the control group were shown 40 photographs at random of attractive, young women dressed in appealing, short and long dresses and asked whether these women were objects of sexual desire or love. The patient with the damaged anterior insula showed a much slower response when asked if the women in the photos could be objects of love.”The current work makes it possible to disentangle love from other biological drives,” the authors wrote. Such studies also could help researchers examine feelings of love by studying neurological activity rather than subjective questionnaires.The full article can be found online at: https://hpenlaboratory.uchicago.edu/sites/caciopponeurolab.uchicago.edu/files/uploads/Cacioppo%20et%20al_Current%20Trends%20in%20Neurology%202013.pdfStory Source:The above story is based on materials provided by University of Chicago. Note: Materials may be edited for content and length.

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Testes size correlates with men’s involvement in toddler care

Sep. 9, 2013 — Men with smaller testes than others are more likely to be involved in hands-on care of their toddlers, a new study conducted by anthropologists at Emory University finds. The Proceedings of the National Academy of Sciences (PNAS) published the results of the study Sept. 9.Smaller testicular volumes also correlate with more nurturing-related brain activity in fathers as they are looking at photos of their own children, the study shows. “Our data suggest that the biology of human males reflects a trade-off between investments in mating versus parenting effort,” says Emory anthropologist James Rilling, whose lab conducted the research.The goal of the research is to determine why some fathers invest more energy in parenting than others. “It’s an important question,” Rilling says, “because previous studies have shown that children with more involved fathers have better social, psychological and educational outcomes.”Evolutionary Life History Theory posits that evolution optimizes the allocation of resources toward either mating or parenting so as to maximize fitness. “Our study is the first to investigate whether human anatomy and brain function explain this variance in parenting effort,” says Jennifer Mascaro, who led the study as a post-doctoral fellow in the Rilling lab.While many economic, social and cultural factors likely influence a father’s level of caregiving, the researchers wanted to investigate possible biological links.They knew that lower levels of testosterone in men have been correlated with greater paternal involvement, and that higher levels of the hormone predict divorce as well as polygamy.The testes, in addition to producing testosterone in males, also produce sperm. “Testes volume is more highly correlated with sperm count and quality than with testosterone levels,” Mascaro says.The study included 70 biological fathers who had a child between the ages of 1 and 2, and who were living with the child and its biological mother.The mothers and fathers were interviewed separately about the father’s involvement in hands-on childcare, including tasks such as changing diapers, feeding and bathing a child, staying home to care for a sick child or taking the child to doctor visits.The men’s testosterone levels were measured, and they underwent functional magnetic resonance imaging (fMRI) to measure brain activity as they viewed photos of their own child with happy, sad and neutral expressions, and similar photos of an unknown child and an unknown adult. Then, structural MRI was used to measure testicular volume.The findings showed that both testosterone levels and testes size were inversely correlated with the amount of direct paternal caregiving reported by the parents in the study.And the father’s testes volume also correlated with activity in the ventral tegmental area (VTA), a part of the brain system associated with reward and parental motivation. “The men with smaller testes were activating this brain region to a greater extent when looking at photos of their own child,” Mascaro says.While testosterone levels may be more related to pre-copulatory, intrasexual competition, testicular volume may reflect post-copulatory mating investment, the researchers theorize.Although statistically significant, the correlation between testes size and caregiving was not perfect.”The fact that we found this variance suggests personal choice,” Rilling says. …

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Brain imaging study reveals the wandering mind behind insomnia

Aug. 30, 2013 — new brain imaging study may help explain why people with insomnia often complain that they struggle to concentrate during the day even when objective evidence of a cognitive problem is lacking.”We found that insomnia subjects did not properly turn on brain regions critical to a working memory task and did not turn off ‘mind-wandering’ brain regions irrelevant to the task,” said lead author Sean P.A. Drummond, PhD, associate professor in the department of psychiatry at the University of California, San Diego, and the VA San Diego Healthcare System, and Secretary/Treasurer of the Sleep Research Society. “Based on these results, it is not surprising that someone with insomnia would feel like they are working harder to do the same job as a healthy sleeper.”The research team led by Drummond and co-principal investigator Matthew Walker, PhD, studied 25 people with primary insomnia and 25 good sleepers. Participants had an average age of 32 years. The study subjects underwent a functional magnetic resonance imaging scan while performing a working memory task.Results published in the September issue of the journal Sleep show that participants with insomnia did not differ from good sleepers in objective cognitive performance on the working memory task. However, the MRI scans revealed that people with insomnia could not modulate activity in brain regions typically used to perform the task.As the task got harder, good sleepers used more resources within the working memory network of the brain, especially the dorsolateral prefrontal cortex. Insomnia subjects, however, were unable to recruit more resources in these brain regions. Furthermore, as the task got harder, participants with insomnia did not dial down the “default mode” regions of the brain that are normally only active when our minds are wandering.”The data help us understand that people with insomnia not only have trouble sleeping at night, but their brains are not functioning as efficiently during the day,” said Drummond. “Some aspects of insomnia are as much of a daytime problem as a nighttime problem. …

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Alcohol breaks brain connections needed to process social cues

Aug. 29, 2013 — Alcohol intoxication reduces communication between two areas of the brain that work together to properly interpret and respond to social signals, according to researchers at the University of Illinois at Chicago College of Medicine.Their results were published in the September issue of Psychopharmacology.Previous research has shown that alcohol suppresses activity in the amygdala, the area of the brain responsible for perceiving social cues such as facial expressions.”Because emotional processing involves both the amygdala and areas of the brain located in the prefrontal cortex responsible for cognition and modulation of behavior, we wanted to see if there were any alterations in the functional connectivity or communication between these two brain regions that might underlie alcohol’s effects,” said K. Luan Phan, UIC professor of psychiatry.’Phan and colleagues examined alcohol’s effects on connectivity between the amygdala and the prefrontal cortex during the processing of emotional stimuli — photographs of happy, fearful and angry faces — using functional magnetic resonance imaging, or fMRI, an imaging technique that allows researchers to see which areas of the brain are active during the performance of various tasks.Participants were 12 heavy social drinkers (10 men, two women) with an average age of 23. Their reported average of 7.8 binge drinking episodes per month — defined as consuming five or more drinks for men, and four or more drinks for women -put them at high risk for developing alcohol dependence.The participants were given a beverage containing either a high dose of alcohol (16 percent) or placebo. They then had an fMRI scan as they tried to match photographs of faces with the same expression.They were shown three faces on a screen — one at the top and two at the bottom — and were asked to pick the face on the bottom showing the same emotion as the one on top. The faces were angry, fearful, happy or neutral.When participants processed images of angry, fearful and happy faces, alcohol reduced the coupling between the amygdala and the orbitofrontal cortex, an area of the prefrontal cortex implicated in socio-emotional information processing and decision-making. The researchers also noticed that alcohol reduced the reaction in the amygdala to threat signals — angry or fearful faces.”This suggests that during acute alcohol intoxication, emotional cues that signal threat are not being processed in the brain normally because the amygdala is not responding as it should be,” Phan said.”The amygdala and the prefrontal cortex have a dynamic, interactive relationship. How the amygdala and prefrontal cortex interact enables us to accurately appraise our environment and modulate our reactions to it,” Phan said. “If these two areas are uncoupled, as they are during acute alcohol intoxication, then our ability to assess and appropriately respond to the non-verbal message conveyed on the faces of others may be impaired. This research gives us a much better idea of what is going on in the brain that leads to some of the maladaptive behaviors we see in alcohol intoxication including social disinhibition, aggression and social withdrawal.”Stephanie Gorka and Daniel Fitzgerald from UIC and Andrea King from the University of Chicago also contributed to this research.This research was supported by a Brain Research Foundation Grant.

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New imaging technology promising for several types of cancer

Aug. 29, 2013 — Researchers from University Hospitals Case Medical Center have published findings that a new form of imaging — PET/MRI — is promising for several types of cancer. In an article titled “PET/MRI: Applications in Clinical Imaging,” published in the September issue of Current Radiology Reports, the authors outline their initial clinical experience in diagnosing and staging cancer patients with this novel technology.Working in collaboration with researchers from Philips Healthcare, the team found that PET/MRI provided added value in the diagnosis, staging and treatment planning of colorectal cancers, cervical, uterine, ovarian and pancreatic cancers — as well as in the diagnostic management of pediatric and young adult patients. The researchers examined 145 cancer patients with a double-scanning protocol of PET/CT followed by a PET/MRI performed on the Philips Ingenuity TF PET/MRI system.”Our preliminary experience with this new diagnostic imaging technology proves that it is promising for oncologic applications,” says study lead author Karin Herrmann, MD, radiologist at UH Case Medical Center and Visiting Associate Professor of Radiology at Case Western Reserve University School of Medicine. “We found the PET/MRI enhanced our ability to detect malignant areas and more accurately and confidently diagnose several types of cancers, potentially providing physicians with the ability to improve treatment planning and better monitoring of the disease.”The PET/MRI is a new hybrid imaging modality which brings together the complementary capabilities of MRI (Magnetic Resonance Imaging) and PET (Positron Emission Tomography) scanning to better visualize both functional and anatomical information and to superimpose this information in a combined digital image. The UH Case Medical Center Seidman Cancer Center is the first cancer hospital in the world to house this technology in a purely clinical setting.In a new class of diagnostic imaging modalities, the PET/MRI combines the highest anatomic detail as well as bio-chemical and functional information provided by MRI with the metabolic, molecular and physiologic information from PET. The technology fuses the images to more precisely pinpoint cancer locations and improve the accuracy of disease staging.In the study, the authors’ detailed account summarizes many aspects of the clinical utility of PET/MRI in more accurate detection of cancer and cancer metastasis, use in decision-making, comparisons of detection accuracy across cancers and distinction of benign from malignant lesions in clinical settings.The authors also outline the considerations of reduction in overall radiation imaging exposure with PET/MRI versus other imaging technologies. Given the similar performance of PET/MR compared to PET/ CT in some disease entities, there is potential to decrease radiation exposure in replacing the CT component in PET/CT with MRI. This may especially be an issue in pediatric and young adult patients with need for repetitive follow up imaging.”This hybrid scanner has the potential to improve patient care by increasing understanding of the causes, effects, and development of disease processes to better diagnose cancer and various other diseases,” said study author Norbert Avril, MD, nuclear radiologist at UH Case Medical Center and Professor at Case Western Reserve University School of Medicine. “We are very excited to be among the first to be able to help establish guidelines of how best to use this technology to guide physicians on the value of the PET/MRI in diagnosing and staging various forms of cancer. …

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Migraine may permanently change brain structure

Aug. 28, 2013 — Migraine may have long-lasting effects on the brain’s structure, according to a study published in the August 28, 2013, online issue of Neurology®, the medical journal of the American Academy of Neurology.”Traditionally, migraine has been considered a benign disorder without long-term consequences for the brain,” said study author Messoud Ashina, MD, PhD, with the University of Copenhagen in Denmark. “Our review and meta-analysis study suggests that the disorder may permanently alter brain structure in multiple ways.”The study found that migraine raised the risk of brain lesions, white matter abnormalities and altered brain volume compared to people without the disorder. The association was even stronger in those with migraine with aura.For the meta-analysis, researchers reviewed six population-based studies and 13 clinic-based studies to see whether people who experienced migraine or migraine with aura had an increased risk of brain lesions, silent abnormalities or brain volume changes on MRI brain scans compared to those without the conditions.The results showed that migraine with aura increased the risk of white matter brain lesions by 68 percent and migraine with no aura increased the risk by 34 percent, compared to those without migraine. The risk for infarct-like abnormalities increased by 44 percent for those with migraine with aura compared to those without aura. Brain volume changes were more common in people with migraine and migraine with aura than those with no migraines.”Migraine affects about 10 to 15 percent of the general population and can cause a substantial personal, occupational and social burden,” said Ashina. “We hope that through more study, we can clarify the association of brain structure changes to attack frequency and length of the disease. We also want to find out how these lesions may influence brain function.”

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New technique to help brain cancer patients

Aug. 23, 2013 — A new scanning technique developed by Danish and US researchers reveals how susceptible patients with aggressive brain cancer are to the drugs they receive. The research behind the ground-breaking technique has just been published in Nature Medicine.Each year sees 260 new cases of the most aggressive type of brain cancer in Denmark. Some patients survive only a few months, while others survive for 18 months. Only very few, 3.5%, are alive five years after their diagnosis. A new scanning technique can now reveal how the brain tumour responds to the drug administered:”We have developed an MRI technique which reveals how a patient will respond to the treatment that inhibits the growth of new blood vessels to the tumour. The technique allows us to only select the patients who will actually benefit from the treatment and to quickly initiate or intensify other treatments for non-responding patients,” says Kim Mouridsen, Associate Professor at Aarhus University and head of the research group Neuroimaging Methods at MINDLab, Aarhus University.He has developed the new technique together with researchers from Harvard Medical School.Brain architecture providing important knowledgeAggressive brain cancer is usually treated with drugs that inhibit the growth of new blood vessels, as the most aggressive brain tumours are constantly trying to produce new blood vessels to get oxygen. The treatment alleviates the symptoms, but it also increases the efficacy of radiation therapy because it improves oxygenation.According to Kim Mouridsen, the new technique — Vessel Architectural Imaging — is an important step towards better treatment:”Getting more knowledge about what the blood vessels in the tumour look like will also give us a better understanding of the mechanisms which are decisive for the efficacy of the treatment. And understanding these mechanisms is precisely what we need to be able to develop and improve the treatment of brain tumours in general.”

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Human brains are hardwired for empathy, friendship

Aug. 22, 2013 — Perhaps one of the most defining features of humanity is our capacity for empathy — the ability to put ourselves in others’ shoes. A new University of Virginia study strongly suggests that we are hardwired to empathize because we closely associate people who are close to us — friends, spouses, lovers — with our very selves.”With familiarity, other people become part of ourselves,” said James Coan, a psychology professor in U.Va.’s College of Arts & Sciences who used functional magnetic resonance imaging brain scans to find that people closely correlate people to whom they are attached to themselves. The study appears in the August issue of the journal Social Cognitive and Affective Neuroscience.”Our self comes to include the people we feel close to,” Coan said.In other words, our self-identity is largely based on whom we know and empathize with. Coan and his U.Va. colleagues conducted the study with 22 young adult participants who underwent fMRI scans of their brains during experiments to monitor brain activity while under threat of receiving mild electrical shocks to themselves or to a friend or stranger. The researchers found, as they expected, that regions of the brain responsible for threat response — the anterior insula, putamen and supramarginal gyrus — became active under threat of shock to the self. In the case of threat of shock to a stranger, the brain in those regions displayed little activity. However when the threat of shock was to a friend, the brain activity of the participant became essentially identical to the activity displayed under threat to the self.”The correlation between self and friend was remarkably similar,” Coan said. “The finding shows the brain’s remarkable capacity to model self to others; that people close to us become a part of ourselves, and that is not just metaphor or poetry, it’s very real. …

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Iron is at core of Alzheimer’s disease, study suggests

Aug. 20, 2013 — Alzheimer’s disease has proven to be a difficult enemy to defeat. After all, aging is the No. 1 risk factor for the disorder, and there’s no stopping that.Most researchers believe the disease is caused by one of two proteins, one called tau, the other beta-amyloid. As we age, most scientists say, these proteins either disrupt signaling between neurons or simply kill them.Now, a new UCLA study suggests a third possible cause: iron accumulation.Dr. George Bartzokis, a professor of psychiatry at the Semel Institute for Neuroscience and Human Behavior at UCLA and senior author of the study, and his colleagues looked at two areas of the brain in patients with Alzheimer’s. They compared the hippocampus, which is known to be damaged early in the disease, and the thalamus, an area that is generally not affected until the late stages. Using sophisticated brain-imaging techniques, they found that iron is increased in the hippocampus and is associated with tissue damage in that area. But increased iron was not found in the thalamus.The research appears in the August edition of the Journal of Alzheimer’s Disease.While most Alzheimer’s researchers focus on the buildup of tau or beta-amyloid that results in the signature plaques associated with the disease, Bartzokis has long argued that the breakdown begins much further “upstream.” The destruction of myelin, the fatty tissue that coats nerve fibers in the brain, he says, disrupts communication between neurons and promotes the buildup of the plaques. These amyloid plaques in turn destroy more and more myelin, disrupting brain signaling and leading to cell death and the classic clinical signs of Alzheimer’s.Myelin is produced by cells called oligodendrocytes. …

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High-flying pilots at increased risk of brain lesions

Aug. 19, 2013 — A new study suggests that pilots who fly at high altitudes may be at an increased risk for brain lesions. The study is published in the August 20, 2013, print issue of Neurology®, the medical journal of the American Academy of Neurology.For the study, 102 U-2 United States Air Force pilots and 91 non-pilots between the ages of 26 and 50 underwent MRI brain scans. The scans measured the amount of white matter hyperintensities, or tiny brain lesions associated with memory decline in other neurological diseases. The groups were matched for age, education and health factors.”Pilots who fly at altitudes above 18,000 feet are at risk for decompression sickness, a condition where gas or atmospheric pressure reaches lower levels than those within body tissues and forms bubbles,” said study author Stephen McGuire, MD, with the University of Texas in San Antonio, the US Air Force School of Aerospace Medicine and a Fellow of the American Academy of Neurology. “The risk for decompression sickness among Air Force pilots has tripled from 2006, probably due to more frequent and longer periods of exposure for pilots. To date however, we have been unable to demonstrate any permanent clinical neurocognitive or memory decline.”Symptoms affecting the brain that sometimes accompany decompression sickness include slowed thought processes, confusion, unresponsiveness and permanent memory loss.The study found that pilots had nearly four times the volume and three times the number of brain lesions as non-pilots. The results were the same whether or not the pilots had a history of symptoms of decompression sickness.The research also found that while the lesions in non-pilots were mainly found in the frontal white matter, as occurs in normal aging, lesions in the pilots were evenly distributed throughout the brain.”These results may be valuable in assessing risk for occupations that include high-altitude mountain climbing, deep sea diving and high-altitude flying,” McGuire said.The study was supported by the United States Air Force Surgeon General.

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Computer can read letters directly from the brain

Aug. 19, 2013 — By analysing MRI images of the brain with an elegant mathematical model, it is possible to reconstruct thoughts more accurately than ever before. In this way, researchers from Radboud University Nijmegen have succeeded in determining which letter a test subject was looking at.The journal Neuroimage has accepted the article, which will be published soon.Functional MRI scanners have been used in cognition research primarily to determine which brain areas are active while test subjects perform a specific task. The question is simple: is a particular brain region on or off? A research group at the Donders Institute for Brain, Cognition and Behaviour at Radboud University has gone a step further: they have used data from the scanner to determine what a test subject is looking at.The researchers ‘taught’ a model how small volumes of 2x2x2 mm from the brain scans — known as voxels — respond to individual pixels. By combining all the information about the pixels from the voxels, it became possible to reconstruct the image viewed by the subject. The result was not a clear image, but a somewhat fuzzy speckle pattern. In this study, the researchers used hand-written letters.Prior knowledge improves model performance’After this we did something new’, says lead researcher Marcel van Gerven. ‘We gave the model prior knowledge: we taught it what letters look like. This improved the recognition of the letters enormously. …

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Cosmic turbulences result in star and black hole formation

Aug. 15, 2013 — Just how stars and black holes in the Universe are able to form from rotating matter is one of the big questions of astrophysics. What we do know is that magnetic fields figure prominently into the picture. However, our current understanding is that they only work if matter is electrically well conductive — but in rotating discs this isn’t always the case. Now, a new publication by Helmholtz-Zentrum Dresden-Rossendorf physicists in the scientific journal Physical Review Letters shows how magnetic fields can also cause turbulences within “dead zones,” thus making an important contribution to our current understanding of just how compact objects form in the cosmos.When Johannes Kepler first proposed his laws of planetary motion in the early days of the 17th century, he could not have foreseen the central role cosmic magnetic fields would play in planetary system formation. Today, we know that in the absence of magnetic fields, mass would not be able to concentrate in compact bodies like stars and black holes. One prominent example is our solar system, which formed 4.6 billion years ago through the collapse of a gigantic cloud of gas, whose gravitational pull concentrated particles in its center, culminating in the formation of a large disc. “These accretion discs are extremely stable from a hydrodynamic perspective as according to Kepler’s laws of planetary motion angular momentum increases from the center towards the periphery,” explains HZDR’s own Dr. Frank Stefani. “In order to explain the growth rates of stars and black holes, there has to exist a mechanism, which acts to destabilize the rotating disc and which at the same time ensures mass is transported towards the center and angular momentum towards the periphery.”As early as 1959, Evgenij Velikhov conjectured that magnetic fields are capable of prompting turbulences within stable rotating flows. …

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Sugar helps scientists find and assess prostate tumors

Aug. 15, 2013 — A natural form of sugar could offer a new, noninvasive way to precisely image tumors and potentially see whether cancer medication is effective, by means of a new imaging technology developed at UC San Francisco in collaboration with GE Healthcare.The technology uses a compound called pyruvate, which is created when glucose breaks down in the body and which normally supplies energy to cells. In cancer, however, pyruvate is more frequently converted to a different compound, known as lactate. Previous animal studies showed that scientists could track the levels of pyruvate as it is converted to lactate via magnetic resonance imaging (MRI), by using a technology called hyperpolarization and injecting the hyperpolarized pyruvate into the body. The amount of lactate produced and rate of conversion enabled researchers to precisely detect the limits of a mouse’s tumor, identify which cancers were most aggressive and track early biochemical changes as tumors responded to medication, long before physical changes occurred.Now, a 31-patient study performed by scientists at UCSF and their collaborators at GE Healthcare has shown that the technology is safe in humans and effectively detects tumors in patients with prostate cancer. Findings appeared online in the Aug. 14, 2013, issue of Science Translational Medicine.While this first-in-human study was designed to identify a safe dosage and verify effectiveness, it lays the groundwork for using the technology to diagnose a variety of cancers and track treatment noninvasively, without conducting repeated biopsies.”We now have a safe dose for patients — that was our primary goal,” said Sarah J. Nelson, PhD, a UCSF professor of radiology and director of the Surbeck Laboratory of Advanced Imaging at UCSF, who was lead author on the study and led a diverse team on this project.”In animal models, the amount of lactate over pyruvate is directly related to the aggressiveness of the cancer. We also have a lot of data that show it’s reduced in cancers after treatment,” she said. “This is a very ubiquitous molecule that will be important in tailoring treatments to specific individuals.”Prostate cancer is the most common form of cancer, with more than 200,000 new cases reported each year in the United States, according to the Centers for Disease Control and Prevention. …

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Isolated psychiatric episodes rare, but possible, in common form of autoimmune encephalitis

July 26, 2013 — A small percentage of people diagnosed with a mysterious neurological condition may only experience psychiatric changes — such as delusional thinking, hallucinations, and aggressive behavior — according to a new study by researchers in the Perelman School of Medicine at the University of Pennsylvania. In addition, people who had previously been diagnosed with this disease, called anti-NMDA receptor (anti-NMDAR) encephalitis, had relapses that only involved psychiatric behavior.In an article published Online First in JAMA Neurology, researchers suggest that, while isolated psychiatric episodes are rare in anti-NMDAR encephalitis cases, abnormal test findings or subtle neurological symptoms should prompt screening for the condition, as it is treatable with immunotherapies.Within a large group of 571 patients with confirmed Anti-NMDAR Encephalitis, only 23 patients (4 percent) had isolated psychiatric episodes. Of the 23, 5 patients experienced the onset of behavior changes as their only symptoms, without neurological changes, while 18 patients had psychiatric symptoms emerge at the outset of a relapse of Anti-NMDAR Encephalitis in which no neurological changes were identified. After being treated for the condition, 83 percent of these patients recovered substantially or completely.”While many patients with Anti-NMDAR Encephalitis present with isolated psychiatric symptoms, most of these patients subsequently develop, in a matter of days, additional neurological symptoms which help to make the diagnosis of the disease. In the current study, we find out that a small percentage of patients do not develop neurological symptoms, or sometimes these are very subtle and transitory. Studies using brain MRI and analysis of the cerebrospinal fluid may help to demonstrate signs of inflammation,” said Josep Dalmau, MD, PhD, adjunct professor of Neurology. “For patients who have been previously diagnosed with Anti-NMDAR Encephalitis and are in remission, any behavior change may present a relapse and should be tested quickly and treated aggressively.”Anti-NMDAR Encephalitis is one of the most common forms of autoimmune encephalitis, and symptoms can include psychiatric symptoms, memory issues, speech disorders, seizures, involuntary movements, and loss of consciousness. In an earlier Penn Medicine study, 38 percent of all patients (and 46 percent of females with the condition) were found to have a tumor, most commonly it was an ovarian tumor. When correctly diagnosed and treated early, Anti-NMDAR Encephalitis can be effectively treated.”For patients with new psychotic symptoms that are evaluated in centers where an MRI, EEG or spinal fluid test may not have been administered, there is a chance that Anti-NMDAR Encephalitis may be missed,” said lead author Matthew Kayser, MD, PhD, postdoctoral fellow and attending physician in Psychiatry at Penn. “However, the likelihood of pure or isolated new-onset psychosis to be anti-NMDAR encephalitis gradually decreases if no other symptoms emerge during the first 4 weeks of psychosis.”Anti-NMDAR Encephalitis was first characterized by Penn’s Josep Dalmau, MD, PhD, adjunct professor of Neurology, and David R. …

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Neural origins of hot flashes identified in menopausal women

July 15, 2013 — A new study from neuroscientists at the Wayne State University School of Medicine provides the first novel insights into the neural origins of hot flashes in menopausal women in years. The study may inform and eventually lead to new treatments for those who experience the sudden but temporary episodes of body warmth, flushing and sweating.The paper, “Temporal Sequencing of Brain Activations During Naturally Occurring Thermoregulatory Events,” by Robert Freedman, Ph.D., professor of psychiatry and behavioral neurosciences, founder of the Behavioral Medicine Laboratory and a member at the C.S. Mott Center for Human Growth and Development, and his collaborator, Vaibhav Diwadkar, Ph.D., associate professor of psychiatry and behavioral neurosciences, appears in the June issue of Cerebral Cortex, an Oxford University Press journal.”The idea of understanding brain responses during thermoregulatory events has spawned many studies where thermal stimuli were applied to the skin. But hot flashes are unique because they are internally generated, so studying them presents unique challenges,” said Freedman, the study’s principal investigator. “Our participants had to lie in the MRI scanner while being heated between two body-size heating pads for up to two hours while we waited for the onset of a hot flash. They were heroic in this regard and the study could not have been conducted without their incredible level of cooperation.””Menopause and hot flashes are a significant women’s health issue of widespread general interest,” Diwadkar added. “However, understanding of the neural origins of hot flashes has remained poor. The question has rarely been assessed with in vivo functional neuroimaging. In part, this paucity of studies reflects the technical limitations of objectively identifying hot flashes while symptomatic women are being scanned with MRI. Nothing like this has been published because this is a very difficult study to do.”During the course of a single year, 20 healthy, symptomatic postmenopausal women ages 47 to 58 who reported six or more hot flashes a day were scanned at the School of Medicine’s Vaitkevicius Imaging Center, located in Detroit’s Harper University Hospital.The researchers collected skin conductance levels to identify the onset of flashes while the women were being scanned. …

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Sugar makes cancer light-up in MRI scanners

July 7, 2013 — A new technique for detecting cancer by imaging the consumption of sugar with magnetic resonance imaging (MRI) has been unveiled by UCL scientists. The breakthrough could provide a safer and simpler alternative to standard radioactive techniques and enable radiologists to image tumours in greater detail.The new technique, called ‘glucose chemical exchange saturation transfer’ (glucoCEST), is based on the fact that tumours consume much more glucose (a type of sugar) than normal, healthy tissues in order to sustain their growth.The researchers found that sensitising an MRI scanner to glucose uptake caused tumours to appear as bright images on MRI scans of mice.Lead researcher Dr Simon Walker-Samuel, from the UCL Centre for Advanced Biomedical Imaging (CABI) said: “GlucoCEST uses radio waves to magnetically label glucose in the body. This can then be detected in tumours using conventional MRI techniques. The method uses an injection of normal sugar and could offer a cheap, safe alternative to existing methods for detecting tumours, which require the injection of radioactive material.”Professor Mark Lythgoe, Director of CABI and a senior author on the study, said: “We can detect cancer using the same sugar content found in half a standard sized chocolate bar. Our research reveals a useful and cost-effective method for imaging cancers using MRI — a standard imaging technology available in many large hospitals.”He continued: “In the future, patients could potentially be scanned in local hospitals, rather than being referred to specialist medical centres.”The study is published in the journal Nature Medicine and trials are now underway to detect glucose in human cancers.According to UCL’s Professor Xavier Golay, another senior author on the study: “Our cross-disciplinary research could allow vulnerable patient groups such as pregnant women and young children to be scanned more regularly, without the risks associated with a dose of radiation.”Dr Walker-Samuel added: “We have developed a new state-of-the-art imaging technique to visualise and map the location of tumours that will hopefully enable us to assess the efficacy of novel cancer therapies.”The work was supported by public and charitable funding from the National Institute for Health Research University College London Hospitals Biomedical Research Centre, Cancer Research UK, Engineering and Physical Sciences Research Council (EPSRC) and the British Heart Foundation (BHF).

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