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Showing posts with label BRAIN-COMPUTER INTERFACES. Show all posts
Showing posts with label BRAIN-COMPUTER INTERFACES. Show all posts

New Stanford research finds computers are better judges of personality than friends and family

Written By Unknown on Friday, January 30, 2015 | 5:53 PM

New research shows that a computer's analysis of data can better judge a person's psychological traits than family and friends.
Computers can judge personality traits far more precisely than ever believed, according to newly published research.

In fact, they might do so better than one's friends and colleagues. The study, published Jan. 12 and conducted jointly by researchers at Stanford University and the University of Cambridge, compares the ability of computers and people to make accurate judgments about our personalities. People's judgments were based on their familiarity with the judged individual, while the computer used digital signals – Facebook "likes."

The researchers were Michal Kosinski, co-lead author and a postdoctoral fellow at Stanford's Department of Computer Science; Wu Youyou, co-lead author and a doctoral student at the University of Cambridge; and David Stillwell, a researcher at the University of Cambridge.

According to Kosinski, the findings reveal that by mining a person's Facebook "likes," a computer was able to predict a person's personality more accurately than most of their friends and family. Only a person's spouse came close to matching the computer's results.

The computer predictions were based on which articles, videos, artists and other items the person had liked on Facebook. The idea was to see how closely a computer prediction could match the subject's own scores on the five most basic personality dimensions: openness, conscientiousness, extraversion, agreeableness and neuroticism.

The researchers noted, "This is an emphatic demonstration of the ability of a person's psychological traits to be discovered by an analysis of data, not requiring any person-to-person interaction. It shows that machines can get to know us better than we'd previously thought, a crucial step in interactions between people and computers."

Kosinski, a computational social scientist, pointed out that "the findings also suggest that in the future, computers could be able to infer our psychological traits and react accordingly, leading to the emergence of emotionally intelligent and socially skilled machines."

"In this context," he added, "the human-computer interactions depicted in science fiction films such as Her seem not to be beyond our reach."

He said the research advances previous work from the University of Cambridge in 2013 that showed that a variety of psychological and demographic characteristics could be "predicted with startling accuracy" through Facebook likes.

The study's methodology

In the new study, researchers collected personality self-ratings of 86,220 volunteers using a standard, 100-item long personality questionnaire. Human judges, including Facebook friends and family members, expressed their judgment of a subject's personality using a 10-item questionnaire. Computer-based personality judgments, based on their Facebook likes, were obtained for the participants.

The results showed that a computer could more accurately predict the subject's personality than a work colleague by analyzing just 10 likes; more than a friend or a roommate with 70; a family member with 150; and a spouse with 300 likes.

"Given that an average Facebook user has about 227 likes (and this number is growing steadily), artificial intelligence has a potential to know us better than our closest companions do," wrote Kosinski and his colleagues.

Why are machines better in judging personality than human beings?

Kosinski said that computers have a couple of key advantages over human beings in the area of personality analysis. Above all, they can retain and access large quantities of information, and analyze all this data through algorithms.

This provides the accuracy that the human mind has a hard time achieving due to a human tendency to give too much weight to one or two examples or to lapse into non-rational ways of thinking, the researchers wrote.

Nevertheless, the authors concede that the detection of some personality traits might be best left to human beings, such as "those (traits) without digital footprints and those depending on subtle cognition."

'Digital footprints'

Wu, co-lead author of the study, explains that the plot behind a movie like Her (released in 2013) becomes increasingly realistic. The film involves a man who strikes up a relationship with an advanced computer operating system that promises to be an intuitive entity in its own right.

"The ability to accurately assess psychological traits and states, using digital footprints of behavior, occupies an important milestone on the path toward more social human-computer interactions," said Wu.

Such data-driven decisions could improve people's lives, the researchers said. For example, recruiters could better match candidates with jobs based on their personality, and companies could better match products and services with consumers' personalities.

"The ability to judge personality is an essential component of social living – from day-to-day decisions to long-term plans such as whom to marry, trust, hire or elect as president," said Stillwell.

Dystopia concerns

The researchers acknowledge that this type of research may conjure up privacy concerns about online data mining and tracking the activities of users.

"A future with our habits being an open book may seem dystopian to those who worry about privacy," they wrote.

Kosinski said, "We hope that consumers, technology developers and policymakers will tackle those challenges by supporting privacy-protecting laws and technologies, and giving the users full control over their digital footprints."

In July, Kosinski will begin a new appointment as an assistant professor at Stanford Graduate School of Business.

Source: Stanford university

On the ups and downs of the seemingly idle brain

Cortical colors Inhibitory cells abound in the barrel cortex of the mouse, where three main types were labeled to fluoresce in different colors: PV (red), SOM (blue), and 5HT3aR, which includes VIP and NPY, (green). Image: Connors lab/Brown University
Even when it seems not to be doing much, the brain maintains a baseline of activity in the form of up and down states of bustle and quiet. To accomplish this seemingly simple cycle, it maintains a complex balance between the activity of many excitatory and inhibitory cells, Brown University scientists report in the Journal of Neuroscience.

PROVIDENCE, R.I. [Brown University] — Even in its quietest moments, the brain is never “off.” Instead, while under anesthesia, during slow-wave sleep, or even amid calm wakefulness, the brain’s cortex maintains a cycle of activity and quiet called “up” and “down” states. A new study by Brown University neuroscientists probed deep into this somewhat mysterious cycle in mice, to learn more about how the mammalian brain accomplishes it.

In addition to an apparent role in maintaining a baseline of brain activity, the up and down cycling serves as a model for other ways in which activity across the cortex is modulated, said Garrett Neske, graduate student and lead author. To study how the brain maintains this cycling, he found, is to learn how the brain walks a healthy line between excitement and inhibition as it strives to be idle but ready, a bit like a car at a stoplight.
Garrett Neske To study how the brain maintains up and down cycles is to learn how the brain strives to be idle but ready, a bit like a car at a stoplight. Photo: David Orenstein/Brown University
“It is very important to regulate that balance of excitation and inhibition,” said senior author Barry Connors, professor and chair of neuroscience at Brown. “Too much excitation relative to inhibition you get a seizure, too little you become comatose. So whether you are awake and active and processing information or whether you are in some kind of idling state of the brain, you need to maintain that balance.”

The cycling may seem simple, but what Neske and Connors found in their investigation, published in the Journal of Neuroscience, is that it involves a good deal of complexity. They focused on five different types of cells in a particular area of the mouse cortex and found that all five appear to contribute uniquely to the ups and downs.

Cells in a barrel

Specifically the researchers, including Saundra Patrick, neuroscience research associate and second author, looked at the activity of excitatory pyramidal cells and four kinds of inhibitory interneurons (PV, SOM, VIP and NPY) in different layers of the barrel cortex. That part of the cortex is responsible for processing sensations on the face, including the whiskers.

Neske induced up and down cycles in slices of tissue from the barrel cortex and recorded each cell type’s electrical properties and behaviors, such as its firing rate and the amounts of excitation and inhibition they received from other neurons.

The picture that emerged is that all types of interneurons were active. This included the most abundant interneuron subtype (the fast-spiking PV cell), and the various more slowly spiking subtypes (SOM, VIP, NPY). In fact, Connors said, the latter cells were active at levels similar to or higher than neighboring excitatory cells, contributing strong inhibition during the up state.

One way such findings are important is in how they complement recent ones by another research group at Yale University. In that study scientists looked at a different part of the cortex called the entorhinal cortex. There they found that only one inhibitory neuron, PV, seemed to be doing anything in the up state to balance out the excitement of the pyramidal neurons. The other inhibitory neurons stayed virtually silent. In his study, Neske replicated those results.

Taken together, the studies indicate that even though up and down cycles occur throughout the cortex, they may be regulated differently in different parts.

“It suggests that inhibition plays different roles in persistent activity in these two regions of cortex and it calls for more comparative work to be done among cortical areas,” Neske said. “You can’t just use one cortical region as the model for all inhibitory interneuron function.”

From observation to manipulation

Since observing the different behaviors of the neuron types, Neske has moved on to manipulating them to see what role each of them plays. Using the technique of optogenetics, in which the firing of different neuron types can be activated or suppressed with pulses of colored light, Neske is experimenting with squelching different interneurons to see how their enforced abstention affects the up and down cycle.

When the work is done, he should emerge with an even clearer idea of the brain’s intricate and diligent efforts to remain balanced between excitation and inhibition.

The National Institutes of Health (grants NS-050434, MH-086400, and T32NS062443) and the Defense Advanced Research Projects Agency (grant DARPA-BAA-09-27) supported the research.

Source: Brown University

Gut microbiota influences blood-brain barrier permeability

Written By Unknown on Sunday, January 18, 2015 | 9:27 AM

Uptake of the substance Raclopride in the brain of germ-free versus conventional mice.
Credit: Miklos Toth
A new study in mice, conducted by researchers at Sweden's Karolinska Institutet together with colleagues in Singapore and the United States, shows that our natural gut-residing microbes can influence the integrity of the blood-brain barrier, which protects the brain from harmful substances in the blood. According to the authors, the findings provide experimental evidence that our indigenous microbes contribute to the mechanism that closes the blood-brain barrier before birth. The results also support previous observations that gut microbiota can impact brain development and function.

The blood-brain barrier is a highly selective barrier that prevents unwanted molecules and cells from entering the brain from the bloodstream. In the current study, being published in the journal Science Translational Medicine, the international interdisciplinary research team demonstrates that the transport of molecules across the blood-brain barrier can be modulated by gut microbes -- which therefore play an important role in the protection of the brain.

The investigators reached this conclusion by comparing the integrity and development of the blood-brain barrier between two groups of mice: the first group was raised in an environment where they were exposed to normal bacteria, and the second (called germ-free mice) was kept in a sterile environment without any bacteria.

"We showed that the presence of the maternal gut microbiota during late pregnancy blocked the passage of labeled antibodies from the circulation into the brain parenchyma of the growing fetus," says first author Dr. Viorica Braniste at the Department of Microbiology, Tumor and Cell Biology at Karolinska Institutet. "In contrast, in age-matched fetuses from germ-free mothers, these labeled antibodies easily crossed the blood-brain barrier and was detected within the brain parenchyma."

The team also showed that the increased 'leakiness' of the blood-brain barrier, observed in germ-free mice from early life, was maintained into adulthood. Interestingly, this 'leakiness' could be abrogated if the mice were exposed to fecal transplantation of normal gut microbes. 

The precise molecular mechanisms remain to be identified. However, the team was able to show that so-called tight junction proteins, which are known to be important for the blood-brain barrier permeability, did undergo structural changes and had altered levels of expression in the absence of bacteria.

According to the researchers, the findings provide experimental evidence that alterations of our indigenous microbiota may have far-reaching consequences for the blood-brain barrier function throughout life.

"These findings further underscore the importance of the maternal microbes during early life and that our bacteria are an integrated component of our body physiology," says Professor Sven Pettersson, the principal investigator at the Department of Microbiology, Tumor and Cell Biology. "Given that the microbiome composition and diversity change over time, it is tempting to speculate that the blood-brain barrier integrity also may fluctuate depending on the microbiome. This knowledge may be used to develop new ways for opening the blood-brain-barrier to increase the efficacy of the brain cancer drugs and for the design of treatment regimes that strengthens the integrity of the blood-brain barrier."

Handheld scanner could make brain tumor removal more complete, reducing recurrence

A handheld device that resembles a laser pointer could someday help surgeons remove all of the cells in a brain tumor. Credit: Moritz Kircher
Cancerous brain tumors are notorious for growing back despite surgical attempts to remove them -- and for leading to a dire prognosis for patients. But scientists are developing a new way to try to root out malignant cells during surgery so fewer or none get left behind to form new tumors. The method, reported in the journal ACS Nano, could someday vastly improve the outlook for patients.

Moritz F. Kircher and colleagues at Memorial Sloan Kettering Cancer Center point out that malignant brain tumors, particularly the kind known as glioblastoma multiforme (GBM), are among the toughest to beat. Although relatively rare, GBM is highly aggressive, and its cells multiply rapidly. Surgical removal is one of the main weapons doctors have to treat brain tumors. The problem is that currently, there's no way to know if they have taken out all of the cancerous cells. And removing extra material "just in case" isn't a good option in the brain, which controls so many critical processes. The techniques surgeons have at their disposal today are not accurate enough to identify all the cells that need to be excised. So Kircher's team decided to develop a new method to fill that gap.

The researchers used a handheld device resembling a laser pointer that can detect "Raman nanoprobes" with very high accuracy. These nanoprobes are injected the day prior to the operation and go specifically to tumor cells, and not to normal brain cells. Using a handheld Raman scanner in a mouse model that mimics human GBM, the researchers successfully identified and removed all malignant cells in the rodents' brains. Also, because the technique involves steps that have already made it to human testing for other purposes, the researchers conclude that it has the potential to move readily into clinical trials. Surgeons might be able to use the device in the future to treat other types of brain cancer, they say.

The authors acknowledge funding from the National Institutes of Health.

New genetic clues found in fragile X syndrome

Written By Unknown on Friday, January 16, 2015 | 11:08 PM

Research by Vitaly Klyachko, PhD, and colleagues has shed new light on brain dysfunctions associated with fragile X syndrome. Credit: Robert Boston
Scientists have gained new insight into fragile X syndrome -- the most common cause of inherited intellectual disability -- by studying the case of a person without the disorder, but with two of its classic symptoms.

In patients with fragile X, a key gene is completely disabled, eliminating a protein that regulates electrical signals in the brain and causing a host of behavioral, neurological and physical symptoms. This patient, in contrast, had only a single error in this gene and exhibited only two classic traits of fragile X -- intellectual disability and seizures -- allowing the researchers to parse out a previously unknown role for the gene.

"This individual case has allowed us to separate two independent functions of the fragile X protein in the brain," said co-senior author Vitaly A. Klyachko, PhD, associate professor of cell biology and physiology at Washington University School of Medicine in St. Louis. "By finding the mutation, even in just one patient, and linking it to a partial set of traits, we have identified a distinct function that this gene is responsible for and that is likely impaired in all people with fragile X."

The research, appearing in the Proceedings of the National Academy of Sciences (PNAS) Online Early Edition in December and in the print issue Jan. 5, is by investigators at Washington University and Emory University School of Medicine in Atlanta.

In studying fragile X, researchers' focus long has been on the problems that occur when brain cells receive signals. Like radio transmitters and receivers, brain cells send and receive transmissions in fine tuned ways that separate the signals from the noise. Until recently, most fragile X research has focused on problems with overly sensitive receivers, those that allow in too much information. The new study suggests that fragile X likely also causes overactive transmitters that send out too much information.

"The mechanisms that researchers have long thought were the entirety of the problem with fragile X are obviously still very much in play," Klyachko said. "But this unique case has allowed us to see that something else is going on."

The finding also raises the possibility that drugs recently tested as treatments for fragile X may be ineffective, at least in part, because they only dialed down the brain's receivers, presumably leaving transmitters on overdrive.

Fragile X syndrome results from an inherited genetic error in a gene called FMR1. The error prevents the manufacture of a protein called FMRP. Loss of FMRP is known to affect how cells in the brain receive signals, dialing up the amount of information allowed in. The gene is on the X chromosome, so the syndrome affects males more often and more severely than females, who may be able to compensate for the genetic error if their second copy of FMR1 is normal.

Patients with fragile X have a range of symptoms. One of the mysteries of the syndrome is how loss of a single gene can lead to such a variety of effects in different patients. Some patients are profoundly intellectually disabled, unable to talk or communicate. Others are only mildly affected. Patients often experience seizures, anxiety and impulsive behavior. Typical physical symptoms include enlarged heads, flat feet and distinctive facial features. 
Almost one-third of patients with fragile X also show symptoms of autism spectrum disorders.

To gain insight into what else FMRP might do, the researchers plumbed genetic sequencing data from more than 900 males with intellectual disabilities but without classic fragile X syndrome. They looked for mutations in the FMR1 gene that might impair the protein but not eliminate it entirely. Even in this relatively large sample size, they only found one patient with abnormal FMRP, resulting from a change in a single letter of the gene's DNA code.

Importantly, although this individual has intellectual disability and seizures, his physical features are not typical of the syndrome, and he is not autistic.

To see what effect this mutation might have, geneticist Stephen T. Warren, PhD, and his team at Emory replicated it in mouse brain cells and tested it for the widely known functions of FMRP. To their surprise, this mutated FMRP appeared to work normally. In other words, the patient's brain cells had entirely normal receivers, which appeared to work in ways that were indistinguishable from those in healthy people.

"This single point mutation does not seem to affect the classical, well-known functions of FMRP," said Klyachko, also an associate professor of biomedical engineering. "This patient presents a case of partial fragile X syndrome associated with mutated, rather than absent, FMRP. As far as I know, this is the only known case of this. It's a unique opportunity to parse out the functions of FMRP. What does this mutation impair to cause only two symptoms of fragile X?"

To find out, Warren and his team replicated the mutation in fruit flies.
Surprisingly, according to the researchers, the fruit fly studies indicated that this single mutation increased the number of transmitters in brain cells, implicating a fundamental problem in which the brain's cells send out too many signals.

To verify this mechanism in mammals, they turned to Klyachko's lab at Washington University, which has expertise in understanding how brain cells regulate the sending of electrical signals. Indeed, in past work Klyachko showed that total loss of FMRP in mice disrupts the normal process by which brain cells send signals, causing transmitters to send out too much information. In the new study, they were able to verify the same effect from just the mutation and link it to human disease. This single mutation in FMRP has the same overactivating effect on transmissions as the total loss of the protein.

The researchers said they can't rule out the possibility that additional problems also are caused by this mutation and are present in fragile X. But this research specifies at least one additional dysfunction not previously recognized. Further studies of patients with different partial symptoms of fragile X and different mutations -- if any can be found -- might identify more.

'Microlesions' in epilepsy discovered by novel technique

Clusters of differentially expressed genes predict cellular abnormalities. Credit: Jeffrey Loeb
Using an innovative technique combining genetic analysis and mathematical modeling with some basic sleuthing, researchers have identified previously undescribed microlesions in brain tissue from epileptic patients. The millimeter-sized abnormalities may explain why areas of the brain that appear normal can produce severe seizures in many children and adults with epilepsy.

The findings, by researchers at the University of Illinois at Chicago College of Medicine, Wayne State University and Montana State University, are reported in the journal Brain.
Epilepsy affects about 1 percent of people worldwide. Its hallmark is unpredictable seizures that occur when groups of neurons in the brain abnormally fire in unison. Sometimes epilepsy can be traced back to visible abnormalities in the brain where seizures start, but in many cases, there are no clear abnormalities or scaring that would account for the epileptic activity.

"Understanding what is wrong in human brain tissues that produce seizures is critical for the development of new treatments because roughly one third of patients with epilepsy don't respond to our currently available medications," said Dr. Jeffrey Loeb, professor and head of neurology and rehabilitation in the UIC College of Medicine and corresponding author on the study. "Knowing these microlesions exist is as huge step forward in our understanding of human epilepsy and present new targets for treating this disease."

Loeb and colleagues searched for cellular changes associated with epilepsy by analyzing thousands genes in tissues from 15 patients who underwent surgery to treat their epilepsy. They used a mathematical modeling technique called cluster analysis to sort through huge amounts of genetic data.

Using the model, they were able to predict and then confirm the presence of tiny regions of cellular abnormalities -- the microlesions -- in human brain tissue with high levels of epileptic electrical activity, or 'high-spiking' areas where seizures begin.

"Using cluster analysis is like using a metal detector to find a needle in a haystack," said Loeb. The model, he said, revealed 11 gene clusters that "jumped right out at us" and were either up-regulated or down-regulated in tissue with high levels of epileptic electrical activity compared to tissue with less epileptic activity from the same patient.

When they matched the genes to the types of cells they came from, the results predicted that there would be reductions of certain types of neurons and increases in blood vessels and inflammatory cells in brain tissue with high epileptic activity.

When Fabien Dachet, an expert in bioinformatics research at UIC and first author of the study, went back to the tissue samples and stained for these cells, he found that all of the prediction were correct- there was a marked increase in blood vessels, inflammatory cells, and there were focal microlesions made up of neurons that had lost most of their normal connections that allow them to communicate with one another. "We think that these newly found microlesions lead to spontaneous, abnormal electrical currents in the brain that lead to epileptic seizures," said Loeb.

Loeb and his colleagues at UIC are using the same approach to look for the clusters of differentially expressed genes associated with ALS, a neurodegenerative disease, and in brain tumors. "We now have a way to predict cellular changes by simply measuring the genetic composition, with some fairly simple calculations, between more- and less-affected epileptic human tissues," explained Loeb.

"This technique gives us the ability to discover previously unknown cellular abnormalities in almost any disease where we have access to human tissues," Loeb said. He is currently developing at UIC a national 'neurorepository' of electrically mapped and genetically analyzed brain tissue for such studies.

Slow to mature, quick to distract: ADHD brain study finds slower development of key connections

By examining hundreds of fMRI brain scans of children with ADHD and those without, the researchers identified key connections between brain networks that matured more slowly in ADHD brains.
Credit: Sripada lab, University of Michigan
A peek inside the brains of more than 750 children and teens reveals a key difference in brain architecture between those with attention deficit hyperactivity disorder and those without.

Kids and teens with ADHD, a new study finds, lag behind others of the same age in how quickly their brains form connections within, and between, key brain networks.

The result: less-mature connections between a brain network that controls internally-directed thought (such as daydreaming) and networks that allow a person to focus on externally-directed tasks. That lag in connection development may help explain why people with ADHD get easily distracted or struggle to stay focused.

What's more, the new findings, and the methods used to make them, may one day allow doctors to use brain scans to diagnose ADHD -- and track how well someone responds to treatment. This kind of neuroimaging "biomarker" doesn't yet exist for ADHD, or any psychiatric condition for that matter.

The new findings come from a team in the University of Michigan Medical School's Department of Psychiatry. They used highly advanced computing techniques to analyze a large pool of detailed brain scans that were publicly shared for scientists to study. Their results are published in the Proceedings of the National Academy of Sciences.

Lead author Chandra Sripada, M.D., Ph.D., and colleagues looked at the brain scans of 275 kids and teens with ADHD, and 481others without it, using "connectomic" methods that can map interconnectivity between networks in the brain.

The scans, made using function magnetic resonance imaging (fMRI) scanners, show brain activity during a resting state. This allows researchers to see how a number of different brain networks, each specialized for certain types of functions, were "talking" within and amongst themselves.

The researchers found lags in development of connection within the internally-focused network, called the default mode network or DMN, and in development of connections between DMN and two networks that process externally-focused tasks, often called task-positive networks, or TPNs. They could even see that the lags in connection development with the two task-related networks -- the frontoparietal and ventral attention networks -- were located primarily in two specific areas of the brain.

The new findings mesh well with what other researchers have found by examining the physical structure of the brains of people with and without ADHD in other ways.
Such research has already shown alterations in regions within DMN and TPNs. So, the new findings build on that understanding and add to it.

The findings are also relevant to thinking about the longitudinal course of ADHD from childhood to adulthood. For instance, some children and teens "grow out" of the disorder, while for others the disorder persists throughout adulthood. Future studies of brain network maturation in ADHD could shed light into the neural basis for this difference.

"We and others are interested in understanding the neural mechanisms of ADHD in hopes that we can contribute to better diagnosis and treatment," says Sripada, an assistant professor and psychiatrist who holds a joint appointment in the U-M Philosophy department and is a member of the U-M Center for Computational Medicine and Bioinformatics. "But without the database of fMRI images, and the spirit of collaboration that allowed them to be compiled and shared, we would never have reached this point."

Sripada explains that in the last decade, functional medical imaging has revealed that the human brain is functionally organized into large-scale connectivity networks. These networks, and the connections between them, mature throughout early childhood all the way to young adulthood. "It is particularly noteworthy that the networks we found to have lagging maturation in ADHD are linked to the very behaviors that are the symptoms of ADHD," he says.

Studying the vast array of connections in the brain, a field called connectomics, requires scientists to be able to parse through not just the one-to-one communications between two specific brain regions, but the patterns of communication among thousands of nodes within the brain. This requires major computing power and access to massive amounts of data -- which makes the open sharing of fMRI images so important.

"The results of this study set the stage for the next phase of this research, which is to examine individual components of the networks that have the maturational lag," he says. 

"This study provides a coarse-grained understanding, and now we want to examine this phenomenon in a more fine-grained way that might lead us to a true biological marker, or neuromarker, for ADHD."

Sripada also notes that connectomics could be used to examine other disorders with roots in brain connectivity -- including autism, which some evidence has suggested stems from over-maturation of some brain networks, and schizophrenia, which may arise from abnormal connections. Pooling more fMRI data from people with these conditions, and depression, anxiety, bipolar disorder and more could boost connectomics studies in those fields.
Volunteers needed for research:

To develop such a neuromarker, Sripada has embarked on follow-up research. One study is enrolling children between the ages of 7 and 17 who have ADHD and a comparison group of those without it; information is at http://umhealth.me/adhdchild. Another study is enrolling adults between the ages of 18 and 35 who have ADHD and a comparison group of those without it; information is at http://umhealth.me/adhdadult. Of note, fMRI scans do not expose a person to radiation. Anyone interested in these studies can email Psych-study@med.umich.edu or call (734) 232-0353; for the study of children, parents should make the contact and consent to research on behalf of their children.

Source: University of Michigan Health System

New way to diagnose brain damage from concussions, strokes, and dementia

Written By Unknown on Thursday, January 15, 2015 | 10:56 PM

A new tool to assess cerebrovascular health: Coherent Hemodynamics Spectroscopy (CHS).
Credit: Tufts University Professor of Biomedical Engineering Sergio Fantini
New optical diagnostic technology developed at Tufts University School of Engineering promises new ways to identify and monitor brain damage resulting from traumatic injury, stroke or vascular dementia -- in real time and without invasive procedures.

Coherent hemodynamics spectroscopy (CHS), developed and published by Tufts Professor of Biomedical Engineering Sergio Fantini, measures blood flow, blood volume, and oxygen consumption in the brain. It uses non-invasive near infrared (NIR) light technology to scan brain tissue, and then applies mathematical algorithms to interpret that information.

"CHS is based on measurements of brain hemodynamics that are interpreted according to unique algorithms that generate measures of cerebral blood flow, blood volume and oxygen consumption," says Fantini. "This technique can be used not only to assess brain diseases but also to study the blood flow and how it is regulated in the healthy brain."

Tufts has licensed CHS on a non-exclusive basis to ISS, a Champaign, Ill.-based company that specializes in technology to measure hemoglobin concentration and oxygenation in brain and muscle tissue.

"Potentially the market for CHS is large as it encompasses several applications from the monitoring of cerebrovascular disorders to assessing neurological disorders," says Beniamino Barbieri, president of ISS. "It reminds me of the introduction of ultrasound technology at beginning of the seventies; nobody back then knew how to utilize the new technology and of course, nowadays, its applications are ubiquitous in any medical center."

How It Works

CHS uses laser diodes which emit NIR light that is delivered to the scalp by fiber optics. Light waves are absorbed by the blood vessels in the brain. Remaining light is reflected back to sensors, resulting in optical signals that oscillate with time as a result of the heartbeat, respiration, or other sources of variations in the blood pressure.

By analyzing the light signals with algorithms developed for this purpose, Fantini's model is able to evaluate blood flow and the way the brain regulates it--which is one marker for brain health.

CHS technology has been tested among patients undergoing hemodialysis at Tufts Medical Center. Published research reported a lower cerebral blood flow in dialysis patients compared with healthy patients.

"Non-invasive ways to measure local changes in cerebral blood flow, particularly during periods of stress such as hemodialysis, surgeries, and in the setting of stroke, could have major implications for maintaining healthy brain function," says Daniel Weiner, M.D., a nephrologist at Tufts Medical Center (Tufts MC) and associate professor of medicine at Tufts University School of Medicine (TUSM), who is a member of the research team.

Josh Kornbluth, M.D., a neurologist at Tufts MC and associate professor of medicine at TUSM, is also working with Fantini to explore CHS's potential to assess the cerebrovascular state of patients who suffer traumatic brain injury or stroke. They hope to test CHS further among neurological critical care patients.

"Having data about local cerebral blood flow and whether it is properly regulated can allow us to more accurately develop individualized therapy and interventions instead of choosing a 'one size fits all' approach to traumatic brain injury, stroke, or subarachnoid hemorrhage," Kornbluth says.

Football players found to have brain damage from mild 'unreported' concussions

Written By Unknown on Wednesday, January 14, 2015 | 6:20 PM

The images from the Ben-Gurion University of the Negev JAMA Neurology study represent Blood-Brain Barrier (BBB) Permeability in Football Players (A) vs. a control group (B). The players in the pathological-BBB group (B) presented focal BBB lesions in different cortical regions including the temporal (player 4), frontal (player 5), and parietal (player 6) lobes. Both gray and white matter were involved. Credit: Image courtesy of American Associates, Ben-Gurion University of the Negev
A new, enhanced MRI diagnostic approach was, for the first time, able to identify significant damage to the blood-brain barrier (BBB) of professional football players following "unreported" trauma or mild concussions. Published in the current issue of JAMA Neurology, this study could improve decision making on when an athlete should "return to play."

According to Prof. Alon Friedman, from the Ben-Gurion University Brain Imaging Research Center and discoverer of the new diagnostic, "until now, there wasn't a diagnostic capability to identify mild brain injury early after the trauma. In the NFL, other professional sports and especially school sports, concern has grown about the long-term neuropsychiatric consequences of repeated mild Traumatic Brain Injury (mTBI) and specifically sports-related concussive and sub-concussive head impacts."

The paper, published by researchers at Ben-Gurion University of the Negev (BGU) and Soroka University Medical Center, describes a new diagnostic approach using Magnetic Resonance Imaging (MRI) for detection and localization of vascular pathology and blood-brain barrier breakdown in football players.

The images from the Ben-Gurion University of the Negev JAMA Neurology study represent Blood-Brain Barrier (BBB) Permeability in Football Players (A) vs. a control group (B). The players in the pathological-BBB group (B) presented focal BBB lesions in different cortical regions including the temporal (player 4), frontal (player 5), and parietal (player 6) lobes. Both gray and white matter were involved.

"The goal of our study was to use our new method to visualize the extent and location of BBB dysfunction in football players using Dynamic Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) on a Phillips 3-T Ingenia. Specifically, it generates more detailed brain maps showing brain regions with abnormal vasculature, or a 'leaky BBB.' "

Study participants included 16 football players from Israel's professional football team, Black Swarm, as well as 13 track and field athletes from Ben-Gurion University who served as controls. All underwent the newly developed MRI-based diagnostic.

The DCE-MRIs were given between games during the season and revealed significant damage.

Forty percent of the examined football players with unreported concussions had evidence of "leaky BBB" compared to 8.3 percent of the control athletes.

"The group of 29 volunteers was clearly differentiated into an intact-BBB group and a pathological-BBB group," Friedman explains. "This showed a clear association between football and increased risk for BBB pathology that we couldn't see before. In addition, high-BBB permeability was found in six players and in only one athlete from the control group."

Friedman also explains that not all the players showed pathology. This indicates that repeated, mild concussive events might impact some players differently than others. This level of diagnosis of individual players can provide the basis of more rational decision making on "return to play" for professionals as well amateurs of any age.

"Generally, players return to the game long before the brain's physical healing is complete, which could exacerbate the possibility of brain damage later in life," says Friedman.

A decade of research in the BGU Laboratory for Experimental Neurosurgery has shown that vascular pathology, and specifically dysfunction of the blood-brain barrier (BBB), plays a key role in brain dysfunction and degeneration, and may be an underlying cause of neurodegenerative complications after brain injuries.

The BBB is a highly selective permeable membrane that separates circulating blood from extracellular fluid. It protects the brain by preventing many dangerous substances from penetrating, and therefore is not meant to be damaged.

Medical researchers, including Friedman's group at BGU, are working to find ways to find drugs that will target the BBB and facilitate its repair, allowing for the prevention of Alzheimer's disease and other brain-related disease.

"Prof. Friedman has been able to conduct this breakthrough brain research using the state-of-the-art MRI machine donated as a result of contributions from American Associates, Ben-Gurion University of the Negev (AABGU)," explains Doron Krakow, AABGU executive vice president. "We believe that with continued support, Prof. Friedman and the DCE-MRI can help render more accurate and informed decisions by athletes and others exposed to mild concussions about when to resume activities."

Source: American Associates, Ben-Gurion University of the Negev

That smartphone is giving your thumbs superpowers

Written By Unknown on Tuesday, January 6, 2015 | 10:41 PM

While neuroscientists have long studied brain plasticity in expert groups--musicians or video gamers, for instance--smartphones present an opportunity to understand how regular life shapes the brains of regular people. Credit: © Antonioguillem / Fotolia
When people spend time interacting with their smartphones via touchscreen, it actually changes the way their thumbs and brains work together, according to a report in the Cell Press journal Current Biology on December 23. More touchscreen use in the recent past translates directly into greater brain activity when the thumbs and other fingertips are touched, the study shows.

"I was really surprised by the scale of the changes introduced by the use of smartphones," says Arko Ghosh of the University of Zurich and ETH Zurich in Switzerland. "I was also struck by how much of the inter-individual variations in the fingertip-associated brain signals could be simply explained by evaluating the smartphone logs."

It all started when Ghosh and his colleagues realized that our newfound obsession with smartphones could be a grand opportunity to explore the everyday plasticity of the human brain. Not only are people suddenly using their fingertips, and especially their thumbs, in a new way, but many of us are also doing it an awful lot, day after day. Not only that, but our phones are also keeping track of our digital histories to provide a readymade source of data on those behaviors.

Ghosh explains it this way: "I think first we must appreciate how common personal digital devices are and how densely people use them. What this means for us neuroscientists is that the digital history we carry in our pockets has an enormous amount of information on how we use our fingertips (and more)."

While neuroscientists have long studied brain plasticity in expert groups--musicians or video gamers, for instance--smartphones present an opportunity to understand how regular life shapes the brains of regular people.

To link digital footprints to brain activity in the new study, Ghosh and his team used electroencephalography (EEG) to record the brain response to mechanical touch on the thumb, index, and middle fingertips of touchscreen phone users in comparison to people who still haven't given up their old-school mobile phones.

The researchers found that the electrical activity in the brains of smartphone users was 
enhanced when all three fingertips were touched. In fact, the amount of activity in the cortex of the brain associated with the thumb and index fingertips was directly proportional to the intensity of phone use, as quantified by built-in battery logs. The thumb tip was even sensitive to day-to-day fluctuations: the shorter the time elapsed from an episode of intense phone use, the researchers report, the larger was the cortical potential associated with it.

The results suggest to the researchers that repetitive movements over the smooth touchscreen surface reshape sensory processing from the hand, with daily updates in the brain's representation of the fingertips. And that leads to a pretty remarkable idea: "We propose that cortical sensory processing in the contemporary brain is continuously shaped by personal digital technology," Ghosh and his colleagues write.

What exactly this influence of digital technology means for us in other areas of our lives is a question for another day. The news might not be so good, Ghosh and colleagues say, noting evidence linking excessive phone use with motor dysfunctions and pain.

Source: Cell Press

Don't get hacked! Research shows how much we ignore online warnings

For their study, BYU researchers created this screen to simulate hacking into participants' laptops. Credit: Image courtesy of Brigham Young University
Say you ignored one of those "this website is not trusted" warnings and it led to your computer being hacked. How would you react? Would you:

A. Quickly shut down your computer?
B. Yank out the cables?
C. Scream in cyber terror?

For a group of college students participating in a research experiment, all of the above were true. These gut reactions (and more) happened when a trio of Brigham Young University researchers simulated hacking into study participants' personal laptops.

"A lot of them freaked out -- you could hear them audibly make noises from our observation rooms," said Anthony Vance, assistant professor of Information Systems. "Several rushed in to say something bad had happened."

Fortunately for the students, nothing bad had really happened. What they saw -- a message from an "Algerian hacker" with a laughing skull and crossbones, a 10-second countdown timer and the words "Say goodbye to your computer" -- wasn't real. What was real was that all of the participants got the message by ignoring web security warnings.

Vance and BYU colleagues Bonnie Anderson and Brock Kirwan carried out the experiment to better understand how people deal with online security risks, such as malware. They found that people say they care about keeping their computers secure, but behave otherwise -- in this case, they plowed through malware warnings.

"We see these messages so much that we stop thinking about them," Vance said. "In a sense, we don't even see them anymore, and so we often ignore them and proceed anyway."

For the study, researchers first asked participants how they felt about online security. Then, in a seemingly unrelated task, participants were told to use their own laptops to log on to a website to categorize pictures of Batman as animated or photographed. (Students were told their image classification project was being used to check the accuracy of a computer algorithm to do the same task.)

As participants clicked through the image pages, warning signs would randomly pop up indicating malware issues with the site they were accessing. If they ignored the message enough times, they were "hacked."

"A lot of people don't realize that they are the weakest link in their computer security," said Kirwan, assistant professor of Psychology and Neuroscience at BYU. "The operating systems we use have a lot of built-in security and the way for a hacker to get control of your computer is to get you to do something."

Kirwan's role in the research added another fascinating layer: Using his expertise in neuroscience, Kirwan carried out an additional experiment on subjects using EEG machines to measure brain responses to risk.

While results showed that people say they care about web security but behave like they don't; they do behave in-line with what their brains say. In other words, people's brainwaves better predict how risky they are with online security.

"We learned that brain data is a better predictor of security behavior than a person's own response," Vance said. "With neuroscience, we're trying to understand this weakest link and understand how we can fortify it."

Anderson, an associate professor of Information Systems, echoed the need to do so, quoting security expert Bruce Schneier: "Only amateurs attack machines; professionals target people."

Thumbs-up for mind-controlled robotic arm

Written By Unknown on Monday, January 5, 2015 | 9:58 PM

This is an image showing one of four new hand movements from the 10D control of the robotic arm. Credit: Journal of Neural Engineering/IOP Publishing
A paralysed woman who controlled a robotic arm using just her thoughts has taken another step towards restoring her natural movements by controlling the arm with a range of complex hand movements.

Thanks to researchers at the University of Pittsburgh, Jan Scheuermann, who has longstanding quadriplegia and has been taking part in the study for over two years, has gone from giving "high fives" to the "thumbs-up" after increasing the manoeuvrability of the robotic arm from seven dimensions (7D) to 10 dimensions (10D).

The extra dimensions come from four hand movements--finger abduction, a scoop, thumb extension and a pinch--and have enabled Jan to pick up, grasp and move a range of objects much more precisely than with the previous 7D control.

It is hoped that these latest results, which have been published today, 17 December, in IOP Publishing's Journal of Neural Engineering, can build on previous demonstrations and eventually allow robotic arms to restore natural arm and hand movements in people with upper limb paralysis.

Jan Scheuermann, 55, from Pittsburgh, PA had been paralysed from the neck down since 2003 due to a neurodegenerative condition. After her eligibility for a research study was confirmed in 2012, Jan underwent surgery to be fitted with two quarter-inch electrode grids, each fitted with 96 tiny contact points, in the regions of Jan's brain that were responsible for right arm and hand movements.

After the electrode grids in Jan's brain were connected to a computer, creating a brain-machine interface (BMI), the 96 individual contact points picked up pulses of electricity that were fired between the neurons in Jan's brain.

Computer algorithms were used to decode these firing signals and identify the patterns associated with a particular arm movement, such as raising the arm or turning the wrist.
By simply thinking of controlling her arm movements, Jan was then able to make the robotic arm reach out to objects, as well as move it in a number of directions and flex and rotate the wrist. It also enabled Jan to "high five" the researchers and feed herself dark chocolate.

Two years on from the initial results, the researchers at the University of Pittsburgh have now shown that Jan can successfully manoeuvre the robotic arm in a further four dimensions through a number of hand movements, allowing for more detailed interaction with objects.

The researchers used a virtual reality computer program to calibrate Jan's control over the robotic arm, and discovered that it is crucial to include virtual objects in this training period in order to allow reliable, real-time interaction with objects.

Co-author of the study Dr Jennifer Collinger said: "10D control allowed Jan to interact with objects in different ways, just as people use their hands to pick up objects depending on their shapes and what they intend to do with them. We hope to repeat this level of control with additional participants and to make the system more robust, so that people who might benefit from it will one day be able to use brain-machine interfaces in daily life.

"We also plan to study whether the incorporation of sensory feedback, such as the touch and feel of an object, can improve neuroprosthetic control."

Commenting on the latest results, Jan Scheuermann said: ""This has been a fantastic, thrilling, wild ride, and I am so glad I've done this."

"This study has enriched my life, given me new friends and co-workers, helped me contribute to research and taken my breath away. For the rest of my life, I will thank God every day for getting to be part of this team."

Controlling genes with your thoughts

Written By Unknown on Tuesday, December 23, 2014 | 5:05 AM

Thoughts control a near-infrared LED, which starts the production of a molecule in a reaction chamber. Credit: Martin Fussenegger et al., Copyright ETH Zurich
It sounds like something from the scene in Star Wars where Master Yoda instructs the young Luke Skywalker to use the force to release his stricken X-Wing from the swamp: Marc Folcher and other researchers from the group led by Martin Fussenegger, Professor of Biotechnology and Bioengineering at the Department of Biosystems (D-BSSE) in Basel, have developed a novel gene regulation method that enables thought-specific brainwaves to control the conversion of genes into proteins -- called gene expression in technical terms.

"For the first time, we have been able to tap into human brainwaves, transfer them wirelessly to a gene network and regulate the expression of a gene depending on the type of thought. Being able to control gene expression via the power of thought is a dream that we've been chasing for over a decade," says Fussenegger.

A source of inspiration for the new thought-controlled gene regulation system was the game Mindflex, where the player wears a special headset with a sensor on the forehead that records brainwaves. The registered electroencephalogram (EEG) is then transferred into the playing environment. The EEG controls a fan that enables a small ball to be thought-guided through an obstacle course.

Wireless Transmission to Implant

The system, which the Basel-based bioengineers recently presented in the journal Nature Communications, also makes use of an EEG headset. The recorded brainwaves are analysed and wirelessly transmitted via Bluetooth to a controller, which in turn controls a field generator that generates an electromagnetic field; this supplies an implant with an induction current.

A light then literally goes on in the implant: an integrated LED lamp that emits light in the near-infrared range turns on and illuminates a culture chamber containing genetically modified cells. When the near-infrared light illuminates the cells, they start to produce the desired protein.

Thoughts Control Protein Quantity

The implant was initially tested in cell cultures and mice, and controlled by the thoughts of various test subjects. The researchers used SEAP for the tests, an easy-to-detect human model protein which diffuses from the culture chamber of the implant into the mouse's bloodstream.

To regulate the quantity of released protein, the test subjects were categorised according to three states of mind: bio-feedback, meditation and concentration. Test subjects who played Minecraft on the computer, i.e. who were concentrating, induced average SEAP values in the bloodstream of the mice. When completely relaxed (meditation), the researchers recorded very high SEAP values in the test animals. For bio-feedback, the test subjects observed the LED light of the implant in the body of the mouse and were able to consciously switch the LED light on or off via the visual feedback. This in turn was reflected by the varying amounts of SEAP in the bloodstream of the mice.

New Light-sensitive Gene Construct

"Controlling genes in this way is completely new and is unique in its simplicity," explains Fussenegger. The light-sensitive optogenetic module that reacts to near-infrared light is a particular advancement. The light shines on a modified light-sensitive protein within the gene-modified cells and triggers an artificial signal cascade, resulting in the production of SEAP. Near-infrared light was used because it is generally not harmful to human cells, can penetrate deep into the tissue and enables the function of the implant to be visually tracked.

The system functions efficiently and effectively in the human-cell culture and human-mouse system. Fussenegger hopes that a thought-controlled implant could one day help to combat neurological diseases, such as chronic headaches, back pain and epilepsy, by detecting specific brainwaves at an early stage and triggering and controlling the creation of certain agents in the implant at exactly the right time.

Source: ETH Zurich
 
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