Links for Keyword: Brain imaging

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Behemoth European brain study agrees to drastic reforms

By Martin Enserink The Human Brain Project (HBP) has listened to the critics, the reviewers, and the mediators. At a meeting in Paris, the board of directors of the €1 billion project yesterday approved a series of recommendations for reform, proposed by a mediation committee, which will change both HBP’s governance and its research program. Critics of the troubled project welcome the move. “We are absolutely delighted that the board has adopted these recommendations,” says computational neuroscientist Peter Dayan of University College London, one of the hundreds of researchers who signed an open letter last year calling for a major reorganization of HBP. Dayan was a member of the mediation committee charged with finding a way out of the crisis after the publication of the letter. That panel’s report—a summary of which was released on 10 March—roundly acknowledges that the critics were right. The committee “largely supports and emphasizes the critique voiced by parts of the scientific community regarding objectives, scientific approach, governance and management practices,” the report says. The mediation committee said that HBP, now administered by the Swiss Federal Institute of Technology in Lausanne (EPFL), should be run by a new, international entity. “In a first concrete step towards implementing that vision, the board [of directors] has created a governance working group composed of former or current heads of international scientific organisations,” an HBP press release issued today said. (They include CERN, the European Space Agency, and the European Molecular Biology Laboratory.) © 2015 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 20704 - Posted: 03.21.2015

Magnetic 'rust' controls brain activity

By Emily Underwood Deep brain stimulation, which now involves surgically inserting electrodes several inches into a person's brain and connecting them to a power source outside the skull, can be an extremely effective treatment for disorders such as Parkinson's disease, obsessive compulsive disorder, and depression. The expensive, invasive procedure doesn't always work, however, and can be risky. Now, a study in mice points to a less invasive way to massage neuronal activity, by injecting metal nanoparticles into the brain and controlling them with magnetic fields. Major technical challenges must be overcome before the approach can be tested in humans, but the technique could eventually provide a wireless, nonsurgical alternative to traditional deep brain stimulation surgery, researchers say. "The approach is very innovative and clever," says Antonio Sastre, a program director in the Division of Applied Science & Technology at the National Institute of Biomedical Imaging and Bioengineering in Bethesda, Maryland. The new work provides "a proof of principle." The inspiration to use magnets to control brain activity in mice first struck materials scientist Polina Anikeeva while working in the lab of neuroscientist-engineer Karl Deisseroth at Stanford University in Palo Alto, California. At the time, Deisseroth and colleagues were refining optogenetics, a tool that can switch specific ensembles of neurons on and off in animals with beams of light. © 2015 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 20690 - Posted: 03.14.2015

Mediators call for change to science of Human Brain Project

Alison Abbott Mediators appointed to analyse the rifts within Europe’s ambitious €1-billion (US$1.1-billion) Human Brain Project (HBP) have called for far-reaching changes both in its governance and its scientific programmes. Most significantly, the report recommends that systems neuroscience and cognitive neuroscience should be reinstated into the HBP. The mediation committee, led by engineer Wolfgang Marquardt, director of Germany’s national Jülich Research Centre, sent its final report to the HBP board of directors on 9 March, and issued a press release summarizing its findings. (The full report will not be published until after the board, a 22-strong team of scientists, discusses its contents at a meeting on 17–18 March). The European Commission flagship project, which launched in October 2013, is intended to boost supercomputing through neuroscience, with the aim of simulating the brain in a computer. But the project has been racked by dissent from the outset. In early 2014, a three-person committee of scientists who ran the HBP’s scientific direction revealed that they planned to eliminate cognitive neuroscience from the initiative, which precipitated a mass protest. More than 150 of Europe’s leading neuroscientists signed a letter to the European Commission, complaining about the project’s management and charging that the HBP plan to simulate the brain using only ‘bottom-up’ data on the behaviour of neurons was doomed to failure if it did not include the top-down constraints provided by systems and cognitive neuroscience. © 2015 Nature Publishing Group

Britain’s Oldest Brain.

In Archaeology it is very rare to find any soft tissue remains: no skin, no flesh, no hair and definitely no brains. However, in 2009, archaeologists from York Archaeological Trust found something very surprising at a site in Heslington, York. During the excavation of an Iron-age landscape at the University of York, a skull, with the jaw and two vertebrae still attached, was discovered face down in a pit, without any evidence of what had happened to the rest of its body. At first it looked like a normal skull but it was not until it was being cleaned, that Collection Projects Officer, Rachel Cubitt, discovered something loose inside. “I peered though the hole at the base of the skull to investigate and to my surprise saw a quantity of bright yellow spongy material. It was unlike anything I had seen before.” says Rachel. Sonia O’Connor, from Archaeological Sciences, University of Bradford, was able to confirm that this was brain. With the help of York Hospital’s Mortuary they were able to remove the top of the skull in order to get their first look at this astonishingly well-preserved human brain. Since the discovery, a team of 34 specialists have been working on this brain to study and conserve it as much as possible. By radiocarbon dating a sample of jaw bone, it was determined that this person probably lived in the 6th Century BC, which makes this brain about 2,600 years old. By looking at the teeth and the shape of the skull it is likely this person was a man between 26 and 45 years old. An examination of the vertebrae in the neck tells us that he was first hit hard on the neck, and then the neck was severed with a small sharp knife, for reasons we can only guess. © Copyright York Archaeological Trust 2013-2015.

Human Brain Project votes for leadership change

Alison Abbott Europe’s ambitious but contentious €1-billion Human Brain Project (HBP) has announced changes to its organization in a response to criticisms of its management and scientific trajectory by many high-ranking neuroscientists. On 26 February, the HBP's Board of Directors voted narrowly to disband the three-person executive committee that had run the project, which launched in October 2013 and is intended to boost digital technologies such as supercomputing through collaboration with neuroscience. That decision is expected to be endorsed by HBP’s 85 or so partner universities and research institutes by the end of this week. The revamp comes seven months after 150 top neuroscientists signed a protest letter to the European Commission, charging, among other things, that the committee was acting autocratically and running the project's scientific plans off course. Led by the charismatic but divisive figure of Henry Markram, a neuroscientist at the Swiss Federal Institute of Technology in Lausanne (EPFL) which coordinates the HBP, the committee had stirred up anger last spring when it revealed plans to cut cognitive neuroscience from the initiative. The neuroscientists vowed to boycott the HBP's future phases if their concerns were ignored. An independent mediation committee was established to look into the charges and make recommendations. Its report, which is expected to further shake up the HBP's management, will be published in the next few weeks. In the meantime, the three-person committee's responsibilities will be taken on by the HBP's Board of Directors (currently a 22-strong team of scientists that includes the disbanded executive committee, although they do not have voting rights). © 2015 Nature Publishing Group

People Are More Willing to Dismiss Evidence From Psychology Than Brain Science

By Christian Jarrett Imagine a politician from your party is in trouble for alleged misdemeanors. He’s been assessed by an expert who says he likely has early-stage Alzheimer’s. If this diagnosis is correct, your politician will have to resign, and he’ll be replaced by a candidate from an opposing party. This was the scenario presented to participants in a new study by Geoffrey Munro and Cynthia Munro. A vital twist was that half of the 106 student participants read a version of the story in which the dementia expert based his diagnosis on detailed cognitive tests; the other half read a version in which he used a structural MRI brain scan. All other story details were matched, such as the expert’s years of experience in the field, and the detail provided for the different techniques he used. Overall, the students found the MRI evidence more convincing than the cognitive tests. For example, 69.8 percent of those given the MRI scenario said the evidence the politician had Alzheimer’s was strong and convincing, whereas only 39.6 percent of students given the cognitive tests scenario said the same. MRI data was also seen to be more objective, valid and reliable. Focusing on just those students in both conditions who showed skepticism, over 15 percent who read the cognitive tests scenario mentioned the unreliability of the evidence; none of the students given the MRI scenario cited this reason. In reality, a diagnosis of probable Alzheimer’s will always be made with cognitive tests, with brain scans used to rule out other explanations for any observed test impairments. The researchers said their results are indicative of naive faith in the trustworthiness of brain imaging data. “When one contrasts the very detailed manuals accompanying cognitive tests to the absences of formalized operational criteria to guide the clinical interpretation of structural brain MRI in diagnosing disease, the perception that brain MRI is somehow immune to problems of reliability becomes even more perplexing,” they said. WIRED.com © 2015 Condé Nast.

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 20621 - Posted: 02.26.2015

Neuroscience is coming to the law. Can we keep politics out of it?

By Francis Shen and Dena Gromet Neuroscience is appearing everywhere. And the legal system is taking notice. The past few years have seen the emergence of “neurolaw.” A spread in the NYT Magazine, a best-selling NYT book, a primetime PBS documentary, the first Law and Neuroscience casebook, and a multimillion-dollar investment from the MacArthur Foundation to fund a Research Network on Law and Neuroscience have all fueled interest in how neuroscience might revolutionize the law. The potential implications of neurolaw are broad. For example, future developments in brain science might allow: criminal law to better identify recidivists; tort law to better differentiate between those in real pain and those who are faking; insurance law to more accurately and adequately compensate those with mental illness; and end-of-life law to more ethically treat patients who might be able to communicate only through their thoughts. Increasingly courts, including the U.S. Supreme Court, and legislatures are citing brain evidence. But despite the media coverage, and much enthusiasm from science and legal elites, our new research shows that Americans know very little about neurolaw, and that Republicans and independents may diverge from Democrats in their support for neuroscience based legal reforms. In our study, we conducted an experiment within a national survey of Americans (more details about the survey are in our article). Everyone in the survey was told that, “Recently developed neuroscientific techniques allow researchers to see inside the human brain as never before.”

Using Light to Monitor and Activate Specific Brain Cells

By Ben Thomas The past several years have brought two parallel revolutions in neuroscience. Researchers have begun using genetically encoded sensors to monitor the behavior of individual neurons, and they’ve been using brief pulses of light to trigger certain types of neurons to activate. These two techniques are known collectively as optogenetics—the science of using light to read and activate genetically specified neurons—but until recently, most researchers have used them separately. Though many had tried, no one had succeeded in combining optogenetic readout and stimulation into one unified system that worked in the brains of living animals. But now, a team led by Michael Hausser, a neuroscientist at University College London’s Wolfson Institute for Biomedical Research, has succeeded in creating just such a unified optogenetic input/output system. In a paper published this January in the journal Nature Methods [Scientific American is part of the Nature Publishing Group], the team explain how they’ve used the system to record complex signaling codes used by specific sets of neurons and to “play” those codes back by reactivating the same neural firing patterns they recorded, paving the way to get neural networks in the brains of living animals to recognize and respond to the codes they send. “This is going to be a game-changer,” Hausser says. Conventional optogenetics starts with genes. Certain genes encode instructions for producing light-sensitive proteins. By introducing these genes into brain cells, researchers are able to trick specific populations of those cells—all the neurons in a given brain region that respond to dopamine, for example—to fire their signals in response to tiny pulses of light. © 2015 Scientific American

Expansion Microscopy Stretches Limits of Conventional Microscopes

By JOHN MARKOFF A new laboratory technique enables researchers to see minuscule biological features, such as individual neurons and synapses, at a nearly molecular scale through conventional optical microscopes. In a paper published last week in the journal Science, researchers at M.I.T. said they were able to increase the physical size of cultured cells and tissue by as much as five times while still preserving their structure. The scientists call the new technique expansion microscopy. The idea of making objects larger to make them more visible is a radical solution to a vexing challenge. By extending the resolving power of conventional microscopes, scientists are able to glimpse such biological mysteries as the protein structures that form ion channels and the outline of the membrane that holds the genome within a cell. The researchers have examined minute neural circuits, gaining new insights into local connections in the brain and a better understanding of larger networks. The maximum resolving power of conventional optical microscopes is about 200 nanometers, about half the wavelength of visible light. (By contrast, a human hair is about 500 times wider.) In recent decades, scientists have struggled to push past these limits. Last year, three scientists received a Nobel Prize for a technique in which fluorescent molecules are used to extend the resolving power of optical microscopes. But the technique requires specialized equipment and is costly. With expansion microscopy, Edward S. Boyden, a co-director of the M.I.T. Center for Neurobiological Engineering, and his colleagues were able to observe objects originally measuring just 70 nanometers in cultured cells and brain tissue through an optical microscope. © 2015 The New York Times Company

Vernon Mountcastle, 'father of neuroscience' and longtime member of Johns Hopkins faculty, dies at 9

Vernon Mountcastle, one of Johns Hopkins Medicine's giants of the 20th century, died peacefully at his North Baltimore home on Sunday, with Nancy, his wife of seven decades, and family at his bedside. He was 96. Mountcastle was universally acknowledged as the "father of neuroscience" and served Johns Hopkins with extraordinary dedication for nearly 65 years. A 1942 graduate of the School of Medicine and a member of the faculty since 1948, Mountcastle served as director of the Department of Physiology and head of the Philip Bard Laboratories of Neurophysiology at Johns Hopkins from 1964 to 1980. He later became one of the founding members of Johns Hopkins' Zanvyl Krieger Mind/Brain Institute, where he continued to work until his retirement at 87. Colleagues remember his dedication to the professional development of neuroscientists, fiercely focused work ethic, and devotion to collaborative research. Also see: Mind/Brain's Mountcastle wins NAS award for lifetime of groundbreaking work (Gazette, April 1998) Mountcastle once was dubbed the "Jacques Cousteau of the cortex" for his revolutionary research delving into the unknown depths of the brain and establishing the basis for modern neuroscience. In 1957, he made the breakthrough discovery that revolutionized the concept of how the brain is built. He found that the cells of the cerebral cortex are organized in vertical columns, extending from the surface of the brain down through six layers of the cortex, each column processing a specific kind of information.

Sebastian Seung’s Quest to Map the Human Brain

By GARETH COOK In 2005, Sebastian Seung suffered the academic equivalent of an existential crisis. More than a decade earlier, with a Ph.D. in theoretical physics from Harvard, Seung made a dramatic career switch into neuroscience, a gamble that seemed to be paying off. He had earned tenure from the Massachusetts Institute of Technology a year faster than the norm and was immediately named a full professor, an unusual move that reflected the sense that Seung was something of a superstar. His lab was underwritten with generous funding by the elite Howard Hughes Medical Institute. He was a popular teacher who traveled the world — Zurich; Seoul, South Korea; Palo Alto, Calif. — delivering lectures on his mathematical theories of how neurons might be wired together to form the engines of thought. And yet Seung, a man so naturally exuberant that he was known for staging ad hoc dance performances with Harvard Square’s street musicians, was growing increasingly depressed. He and his colleagues spent their days arguing over how the brain might function, but science offered no way to scan it for the answers. “It seemed like decades could go by,” Seung told me recently, “and you would never know one way or another whether any of the theories were correct.” That November, Seung sought the advice of David Tank, a mentor he met at Bell Laboratories who was attending the annual meeting of the Society for Neuroscience, in Washington. Over lunch in the dowdy dining room of a nearby hotel, Tank advised a radical cure. A former colleague in Heidelberg, Germany, had just built a device that imaged brain tissue with enough resolution to make out the connections between individual neurons. But drawing even a tiny wiring diagram required herculean efforts, as people traced the course of neurons through thousands of blurry black-and-white images. What the field needed, Tank said, was a computer program that could trace them automatically — a way to map the brain’s connections by the millions, opening a new area of scientific discovery. For Seung to tackle the problem, though, it would mean abandoning the work that had propelled him to the top of his discipline in favor of a highly speculative engineering project. © 2015 The New York Times Company

Blown-up brains reveal nanoscale details

Ewen Callaway Microscopes make living cells and tissues appear bigger. But what if we could actually make the things bigger? It might sound like the fantasy of a scientist who has read Alice’s Adventures in Wonderland too many times, but the concept is the basis for a new method that could enable biologists to image an entire brain in exquisite molecular detail using an ordinary microscope, and to resolve features that would normally be beyond the limits of optics. The technique, called expansion microscopy, involves physically inflating biological tissues using a material more commonly found in baby nappies (diapers). Edward Boyden, a neuroengineer at the Massachusetts Institute of Technology (MIT) in Cambridge, discussed the technique, which he developed with his MIT colleagues Fei Chen and Paul Tillberg, at a conference last month. Prizewinning roots Expansion microscopy is a twist on super-resolution microscopy, which earned three scientists the 2014 Nobel Prize in Chemistry. Both techniques attempt to circumvent a limitation posed by the laws of physics. In 1873, German physicist Ernst Abbe deduced that conventional optical microscopes cannot distinguish objects that are closer together than about 200 nanometres — roughly half the shortest wavelength of visible light. Anything closer than this 'diffraction limit' appears as a blur. © 2015 Nature Publishing Group

Researchers read and write brain activity with light

Mo Costandi A team of neuroscientists at University College London has developed a new way of simultaneously recording and manipulating the activity of multiple cells in the brains of live animals using pulses of light. The technique, described today in the journal Nature Methods, combines two existing state-of-the-art neurotechnologies. It may eventually allow researchers to do away with the cumbersome microelectrodes they traditionally used to probe neuronal activity, and to interrogate the brain’s workings at the cellular level in real time and with unprecedented detail. One of them is optogenetics. This involves creating genetically engineered mice expressing algal proteins called Channelrhodopsins in specified groups of neurons. This renders the cells sensitive to light, allowing researchers to switch the cells on or off, depending on which Channelrhodopsin protein they express, and which wavelength of light is used. This can be done on a millisecond-by-millisecond timescale, using pulses of laser light delivered into the animals’ brains via an optical fibre. The other is calcium imaging. Calcium signals are crucial for just about every aspect of neuronal function, and nerve cells exhibit a sudden increase in calcium ion concentration when they begin to fire off nervous impulses. Using dyes that give off green fluorescence in response to increases in calcium concentration, combined with two-photon microscopy, researchers can detect this signature to see which cells are activated. In this way, they can effectively ‘read’ the activity of entire cell populations in brain tissue slices or live brains. Calcium-sensitive dyes are injectable, so targeting them with precision is difficult, and more recently, researchers have developed genetically-encoded calcium sensors to overcome this limitation. Mice can be genetically engineered to express these calcium-sensitive proteins in specific groups of cells; like the dyes before them, they, too, fluoresce in response to increases in calcium ion concentrations in the cells expressing them.

Personality affects maths-enhancing brain-zap method

by Helen Thomson Zapping your brain might make you better at maths tests – or worse. It depends how anxious you are about taking the test in the first place. A recent surge of studies has shown that brain stimulation can make people more creative and better at maths, and can even improve memory, but these studies tend to neglect individual differences. Now, Roi Cohen Kadosh at the University of Oxford and his colleagues have shown that brain stimulation can have completely opposite effects depending on your personality. Previous research has shown that a type of non-invasive brain stimulation called transcranial direct current stimulation (tDCS) – which enhances brain activity using an electric current – can improve mathematical ability when applied to the dorsolateral prefrontal cortex, an area involved in regulating emotion. To test whether personality traits might affect this result, Kadosh's team tried the technique on 25 people who find mental arithmetic highly stressful, and 20 people who do not. They found that participants with high maths anxiety made correct responses more quickly and, after the test, showed lower levels of cortisol, an indicator of stress. On the other hand, individuals with low maths anxiety performed worse after tDCS. "It is hard to believe that all people would benefit similarly [from] brain stimulation," says Cohen Kadosh. He says that further research could shed light on how to optimise the technology and help to discover who is most likely to benefit from stimulation. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 13: Memory, Learning, and Development
Link ID: 20406 - Posted: 12.10.2014

Warning over experimental brain boost

Ian Sample, science editor Electrical brain stimulation equipment – which can boost cognitive performance and is easy to buy online – can have bad effects, impairing brain functioning, research from scientists at Oxford University has shown. A steady stream of reports of stimulators being able to boost brain performance, coupled with the simplicity of the devices, has led to a rise in DIY enthusiasts who cobble the equipment together themselves, or buy it assembled on the web, then zap themselves at home. In science laboratories brain stimulators have long been used to explore cognition. The equipment uses electrodes to pass gentle electric pulses through the brain, to stimulate activity in specific regions of the organ. Roi Cohen Kadosh, who led the study, published in the Journal of Neuroscience, said: “It’s not something people should be doing at home at this stage. I do not recommend people buy this equipment. At the moment it’s not therapy, it’s an experimental tool.” The Oxford scientists used a technique called transcranial direct current stimulation (tDCS) to stimulate the dorsolateral prefrontal cortex in students as they did simple sums. The results of the test were surprising. Students who became anxious when confronted with sums became calmer and solved the problems faster than when they had sham stimulation (the stimulation itself lasted only 30 seconds of the half hour study). The shock was that the students who did not fear maths performed worse with the same stimulation.

Turning Lab Animals Transparent

|By Ryan Bradley Five years ago Viviana Gradinaru was slicing thin pieces of mouse brain in a neurobiology lab, slowly compiling images of the two-dimensional slivers for a three-dimensional computer rendering. In her spare time, she would go to see the Body Worlds exhibit. She was especially fascinated by the “plasticized” remains of the human circulatory system on display. It struck her that much of what she was doing in the lab could be done more efficiently with a similar process. “Tissue clearing” has been around for more than a century, but existing methods involve soaking tissue samples in solvents, which is slow and usually destroys the fluorescent proteins necessary for marking certain cells of interest. To create a better approach, Gradinaru, at the time a graduate student, and her colleagues in neuroscientist Karl Deisseroth's lab focused on replacing the tissue's lipid molecules, which make it opaque.* To keep the tissue from collapsing, however, the replacement would need to give it structure, as lipids do. The first step was to euthanize a rodent and pump formaldehyde into its body, through its heart. Next they removed the skin and filled its blood vessels with acrylamide monomers, white, odorless, crystalline compounds. The monomers created a supportive hydrogel mesh, replacing the lipids and clearing the tissue. Before long, they could render an entire mouse body transparent in two weeks. Soon they were using transparent mice to map complete mouse nervous systems. The transparency made it possible for them to identify peripheral nerves—tiny bundles of nerves that are poorly understood—and to map the spread of viruses across the mouse's blood-brain barrier, which they did by marking the virus with a fluorescent agent, injecting it into the mouse's tail and watching it spread into the brain. © 2014 Scientific American

Watch a tapeworm squirm through a living man's brain

by Linda Geddes A tapeworm that usually infects dogs, frogs and cats has made its home inside a man's brain. Sequencing its genome showed that it contains around 10 times more DNA than any other tapeworm sequenced so far, which could explain its ability to invade many different species. When a 50-year-old Chinese man was admitted to a UK hospital complaining of headaches, seizures, an altered sense of smell and memory flashbacks, his doctors were stumped. Tests for tuberculosis, syphilis, HIV and Lyme disease were negative, and although an MRI scan showed an abnormal region in the right side of his brain, a biopsy found inflammation, but no tumour. Over the next four years, further MRIs recorded the abnormal region moving across the man's brain (see animation), until finally his doctors decided to operate. To their immense surprise, they pulled out a 1 centimetre-long ribbon-shaped worm. It looked like a tapeworm, but was unlike any seen before in the UK, so a sample of its tissue was sent to Hayley Bennett and her colleagues at the Wellcome Trust Sanger Institute in Cambridge, UK. Genetic sequencing identified it as Spirometra erinaceieuropaei, a rare species of tapeworm found in China, South Korea, Japan and Thailand. Just 300 human infections have been reported since 1953, and not all of them in the brain. © Copyright Reed Business Information Ltd.

Failed Replications: A Reality Check for Neuroscience?

By Neuroskeptic An attempt to replicate the results of some recent neuroscience papers that claimed to find correlations between human brain structure and behavior has drawn a blank. The new paper is by University of Amsterdam researchers Wouter Boekel and colleagues and it’s in press now at Cortex. You can download it here from the webpage of one of the authors, Eric-Jan Wagenmakers. Neuroskeptic readers will know Wagenmakers as a critic of statistical fallacies in psychology and a leading advocate of preregistration, which is something I never tire of promoting either. Boekel et al. attempted to replicate five different papers which, together, reported 17 distinct positive results in the form of structural brain-behavior (‘SBB’) correlations. An SBB correlation is an association between the size (usually) of a particular brain area and a particular behavioral trait. For instance, one of the claims was that the amount of grey matter in the amygdala is correlated with the number of Facebook friends you have. To attempt to reproduce these 17 findings, Boekel et al. took 36 students whose brains were scanned with two methods, structural MRI and DWI. The students then completed a set of questionnaires and psychological tests, identical to ones used in the five papers that were up for replication. The methods and statistical analyses were fully preregistered (back in June 2012); Boekel et al. therefore had no scope for ‘fishing’ for positive (or negative) results by tinkering with the methodology. So what did they find? Nothing much. None of the 17 brain-behavior correlations were significant in the replication sample.

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 1: Biological Psychology: Scope and Outlook
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 1: An Introduction to Brain and Behavior
Link ID: 20330 - Posted: 11.20.2014

Sound Waves Can Heal Brain Disorders

|By Bret Stetka The brain is protected by formidable defenses. In addition to the skull, the cells that make up the blood-brain barrier keep pathogens and toxic substances from reaching the central nervous system. The protection is a boon, except when we need to deliver drugs to treat illnesses. Now researchers are testing a way to penetrate these bastions: sound waves. Kullervo Hynynen, a medical physicist at Sunnybrook Research Institute in Toronto, and a team of physicians are trying out a technique that involves giving patients a drug followed by an injection of microscopic gas-filled bubbles. Next patients don a cap that directs sound waves to specific brain locations, an approach called high-intensity focused ultrasound. The waves cause the bubbles to vibrate, temporarily forcing apart the cells of the blood-brain barrier and allowing the medication to infiltrate the brain. Hynynen and his colleagues are currently testing whether they can use the method to deliver chemotherapy to patients with brain tumors. They and other groups are planning similar trials for patients with other brain disorders, including Alzheimer's disease. Physicians are also considering high-intensity focused ultrasound as an alternative to brain surgery. Patients with movement disorders such as Parkinson's disease and dystonia are increasingly being treated with implanted electrodes, which can interrupt problematic brain activity. A team at the University of Virginia hopes to use focused ultrasound to deliver thermal lesions deep into the brain without having patients go under the knife. © 2014 Scientific American

Learning How Little We Know About the Brain

By JAMES GORMAN Research on the brain is surging. The United States and the European Union have launched new programs to better understand the brain. Scientists are mapping parts of mouse, fly and human brains at different levels of magnification. Technology for recording brain activity has been improving at a revolutionary pace. The National Institutes of Health, which already spends $4.5 billion a year on brain research, consulted the top neuroscientists in the country to frame its role in an initiative announced by President Obama last year to concentrate on developing a fundamental understanding of the brain. Scientists have puzzled out profoundly important insights about how the brain works, like the way the mammalian brain navigates and remembers places, work that won the 2014 Nobel Prize in Physiology or Medicine for a British-American and two Norwegians. So many large and small questions remain unanswered. How is information encoded and transferred from cell to cell or from network to network of cells? Science found a genetic code but there is no brain-wide neural code; no electrical or chemical alphabet exists that can be recombined to say “red” or “fear” or “wink” or “run.” And no one knows whether information is encoded differently in various parts of the brain. Brain scientists may speculate on a grand scale, but they work on a small scale. Sebastian Seung at Princeton, author of “Connectome: How the Brain’s Wiring Makes Us Who We Are,” speaks in sweeping terms of how identity, personality, memory — all the things that define a human being — grow out of the way brain cells and regions are connected to each other. But in the lab, his most recent work involves the connections and structure of motion-detecting neurons in the retinas of mice. Larry Abbott, 64, a former theoretical physicist who is now co-director, with Kenneth Miller, of the Center for Theoretical Neuroscience at Columbia University, is one of the field’s most prominent theorists, and the person whose name invariably comes up when discussions turn to brain theory. © 2014 The New York Times Company

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