Patterns of connections reveal brain functions

 

Graphic: Christine Daniloff

For more than a decade, neuroscientists have known that many of the cells in a brain region called the fusiform gyrus specialize in recognizing faces. However, those cells don’t act alone: They need to communicate with several other parts of the brain. By tracing those connections, MIT neuroscientists have now shown that they can accurately predict which parts of the fusiform gyrus are face-selective.

The study, which appeared in the Dec. 25 issue of the journal Nature Neuroscience, is the first to link a brain region’s connectivity with its function. No two people have the exact same fusiform gyrus structure, but using connectivity patterns, the researchers can now accurately predict which parts of an individual’s fusiform gyrus are involved in face recognition.

This work goes a step beyond previous studies that have used magnetic resonance imaging (MRI) to locate the regions that are involved in particular functions. “Rather than just mapping the brain, what we’re doing now is adding on to that a description of function with respect to connectivity,” says David Osher, a lead author of the paper and a graduate student in the lab of John Gabrieli, the Grover Hermann Professor of Health Sciences and Technology and Cognitive Neuroscience and a member of MIT’s McGovern Institute for Brain Research.

Using this approach, scientists may be able to learn more about the face-recognition impairments often seen in autism and prosopagnosia, a disorder often caused by stroke. This method could also be used to determine relationships between structure and function in other parts of the brain.

To map the brain’s connectivity patterns, the researchers used a technique called diffusion-weighted imaging, which is based on MRI. A magnetic field applied to the brain of the person in the scanner causes water in the brain to flow in the same direction. However, wherever there are axons — the long cellular extensions that connect a neuron to other brain regions — water is forced to flow along the axon, rather than crossing it. This is because axons are coated in a fatty material called myelin, which is impervious to water.

By applying the magnetic field in many different directions and observing which way the water flows, the researchers can identify the locations of axons and determine which brain regions they are connecting. 

“For every measurable unit of the brain at this level, we have a description of how it connects with every other region, and with what strength it connects with every other region,” says Zeynep Saygin, a lead author of the paper and a graduate student who is advised by Gabrieli and Rebecca Saxe, senior author of the paper and associate professor of brain and cognitive sciences.

Gabrieli is also an author of the paper, along with Kami Koldewyn, a postdoc in MIT professor Nancy Kanwisher’s lab, and Gretchen Reynolds, a former technical assistant in Gabrieli’s lab.

Making connections

The researchers found that certain patches of the fusiform gyrus were strongly connected to brain regions also known to be involved in face recognition, including the superior and inferior temporal cortices. Those fusiform gyrus patches were also most active when the subjects were performing face-recognition tasks.

Based on the results in one group of subjects, the researchers created a model that predicts function in the fusiform gyrus based solely on the observed connectivity patterns. In a second group of subjects, they found that the model successfully predicted which patches of the fusiform gyrus would respond to faces.

“This is the first time we’ve had direct evidence of this relationship between function and connectivity, even though you certainly would have assumed that was going to be true,” says Saxe, who is also an associate member of the McGovern Institute. “One thing this paper does is demonstrate that the tools we have are sufficient to see something that we strongly believed had to be there, but that we didn’t know we’d be able to see.”

The other regions connected to the fusiform gyrus are believed to be involved in higher-level visual processing. One surprise was that some parts of the fusiform gyrus connect to a part of the brain called the cerebellar cortex, which is not thought to be part of the traditional vision-processing pathway. That area has not been studied very thoroughly, but a few studies have suggested that it might have a role in face recognition, Osher says.

Now that the researchers have an accurate model to predict function of fusiform gyrus cells based solely on their connectivity, they could use the model to study the brains of patients, such as severely autistic children, who can’t lie down in an MRI scanner long enough to participate in a series of face-recognition tasks. That is one of the most important aspects of the study, says Michael Beauchamp, an associate professor of neurobiology at the University of Texas Medical School.

“Functional MRI is the best tool we have for looking at human brain function, but it’s not suitable for all patient groups, especially children or older people with cognitive disabilities,” says Beauchamp, who was not involved in this study.

The MIT researchers are now expanding their connectivity studies into other brain regions and other visual functions, such as recognizing objects and scenes, as well as faces. They hope that such studies will also help to reveal some of the mechanisms of how information is processed at each point as it flows through the brain.

Provided by Massachusetts Institute of Technology

This story is republished courtesy of MIT News (http://web.mit.edu/newsoffice/

 

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"Patterns of connections reveal brain functions." January 3rd, 2012. http://medicalxpress.com/news/2012-01-patterns-reveal-brain-functions.html

 

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A call for an evolved understanding of emotion

 
In a new scholarly review, psychology professor Lisa Feldman Barrett points out that the beliefs about emotion guiding many security practices today may be flawed. Credit: Mary Knox Merrill.

(Medical Xpress) -- Many scientists believe that all people experience and express the same biologically “basic” emotions — an idea they have attributed to evolutionist Charles Darwin and one that has shaped modern security training and law enforcement techniques.

But that belief is not rooted in sound scientific study, says Northeastern’s Lisa Feldman Barrett, Distinguished Professor of Psychology in the College of Science, who wrote a review of recent research for the Association for Psychological Science’s journal, Current Directions in Psychological Science, titled “Was Darwin Wrong About Emotional Expressions?

 

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“It has been assumed for many years that when you feel some emotion, you automatically show that emotion on your face. This belief guides security training at airports, FBI training and so on,” Barrett said. “But there’s a lot of research out there to show that emotions are not written on the face, that there’s a lot of context that a perceiver like you or me brings to the judgment of facial expressions.”

Backers of a “basic” emotions approach cite Darwin, who wrote “Expression of Emotion in Man and Animals” after his famous “Origin of the Species.” That book argued that emotions were states of minds that were automatically expressed across animal species.

“But Darwin’s views were that these emotional expressions were vestigial, more like your tailbone — something that evolution carried forward but which may no longer be of any use,” Barrett said. “So Darwin was arguing that these expressions are no longer functional, thereby showing that they must exist as an inherited characteristic.”

Commonly held beliefs in psychology include that humans automatically express a handful of emotions, like sadness through a frown or anger through a scowl. But recent research — by Barrett’s own lab at Northeastern and others — has challenged that longstanding hypothesis. Instead, the new research shows that small changes in an experiment can lead to dramatically different results. And recent articles published in the journals Nature and Science call into question the use of security-training techniques based on the “basic emotion” approach.

“The fact is, it’s not really clear from the existing evidence that people actually make these expressions on an everyday basis,” Barrett said. “When do people actually pout in sadness? You certainly couldn’t win an Academy Award for pouting in sadness.”

Barrett said that further study of emotion beyond the most popular hypothesis is important, especially since the potentially flawed research has become the basis for law enforcement and homeland security protocols and procedures.

“The idea that facial expressions are a beacon for you to read is just not right,” she said. “It’s a really popular view and you can find data that supports it, but you can also find a tremendous amount of data that does not. That research doesn’t seem to be getting much play, and it needs to.”

Provided by Northeastern University

"A call for an evolved understanding of emotion." January 4th, 2012. http://medicalxpress.com/news/2012-01-evolved-emotion.html

 

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Facing complexity in the left brain/right brain paradigm

Dartmouth Professor Ming Meng investigates image perception differences between the left brain and the right brain. On his monitor, a magnetic resonance image of the brain shows the left and right fusiform gyri. Credit: Eli Burak

The left brain/right brain dichotomy has been prominent on the pop psychology scene since Nobel Laureate Roger Sperry broached the subject in the 1960s. The left is analytical while the right is creative, so goes the adage.

And then there is the quasi-scientific obsession with "the face." Facial recognition technology and facial microexpressions are the stuff of television crime dramas, such as Person of Interest and Lie to Me.

But Ming Meng, an assistant professor in the Department of Psychological and Brain Sciences at Dartmouth College, has brought these two together in a way that offers new insights into the organization of the brain with implications for autism.

Meng and his colleagues have published their findings January 4 in the online edition of the Proceedings of the Royal Society B (Biological Sciences).

Meng's novel approach is to combine functional magnetic resonance imaging (fMRI), computer vision, and psychophysics to take our understanding of brain function in a new direction. He was able to assign distinct complementary aspects of visual information processing to each side of the brain. Meng is interested in perception and considers vision its major domain. His research focuses on how the brain is organized to process visual information.

The traditional approach to visual information processing has been to view it as an ordered sequence. In the early stages of processing, the right side of the brain was thought to process the left visual field and vice versa, whereas in later stages of processing the right and the left brain process the whole visual field in parallel.

"I find such organization puzzling in terms of efficiency with both parts of the brain effectively processing the same thing—a waste of resources," says Meng. Instead, he proposes a division of labor with right side and left doing different things.

Looking at how the brain processes faces is Meng's key to unlocking the mysteries of the left brain/right brain paradigm.

The left and right fusiform gyri (spindle-shaped sections) of the temporal lobes were known to be the places where facial stimuli were processed, and Meng homed in here. "I wondered what the difference might be between the left brain and the right in processing the human face and this was the place to look," he says.

But first he looked to computer-generated images for his experimental materials. Meng felt that fMRI measurement of his test subjects' reactions only to images of faces versus non-faces offered too coarse a distinction.

"We needed to study the full spectrum, the stimuli that makes an image look like a face but not necessarily a face. These results would show the subtle differences between the left and right side of the brain as they dealt with this range of images," he explains. A computer algorithm generated the desired range of images that he then showed to his test subjects while taking fMRI measurements of their brain activity.

Using psychophysics as behavioral testing tools, Meng analyzed the spectrum from random non-faces to genuine faces.

"We were able to systematically quantify the face-semblance of each of our stimuli (images). This is important because otherwise we would only have an oversimplified 'black-white' distinction between faces and non-faces, which would not be particularly useful to differentiate the functional roles of the left and right hemispheres," Meng explains.

"Only with the psychophysical face-semblance ratings, we've found that the left is involved in the graded analysis of the visual stimuli. Our results suggest the left side of the brain is processing the external physical input which resolves into a 'grey scale' while the right brain is underlying the final decision of whether or not it is a face."

Application of Meng's tripartite methodology that has shown the differences in the left brain/right brain picture could provide a template for studying patients with face processing deficits, as well as a new frame of reference for autism.

Faces constitute a particular challenge for autistic children. They typically avoid eye contact, diverting their gaze from another person's face. Meng suggests that, "the underlying reason for their problems with social interaction may be correlated to their problems with face perception."

Knowing the organization of face processing mechanisms in normal individuals provides a good starting point for exploring how this organization might be different in people with autism.

Provided by Dartmouth College

"Facing complexity in the left brain/right brain paradigm." January 4th, 2012. http://medicalxpress.com/news/2012-01-complexity-left-brainright-brain-paradigm.html

 

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Robert Karl Stonjek

GABA signaling prunes back copious 'provisional' synapses during neural circuit assembly

Quite early in its development, the mammalian brain has all the raw materials on hand to forge complex neural networks. But forming the connections that make these intricate networks so exquisitely functional is a process that occurs one synapse at a time. An important question for neuroscience has been: how exactly do stable synapses form? How do nerve cells of particular types know which of their cortical neighbors to "synapse" with, and which to leave out of their emerging networks?

Neuroscientist Z. Josh Huang, a professor at Cold Spring Harbor Laboratory, and his laboratory team spearheaded by graduate student Xiaoyun We tomorrow publish a finding in the Journal of Neuroscience that Huang says surprised them, even after years of work on this problem.

In emerging networks being established by GABA interneurons – inhibitory brain cells named for the neurotransmitting chemical, gamma aminobutyric acid, that they release – Huang's team found strong evidence that the "default state" is for the cell to make tentative connections promiscuously, with almost every available partner. That much they had anticipated.

The unexpected observation was that GABA proved not to be involved in the initial formation of these tentative or "test" synapses, but rather in the essential process of pruning them back, later, after they had been formed. The net effect of provisional synapse formation and rapid subsequent pruning, Huang says, is "a bit like speed dating."

Huang explains that there are two known mechanisms at work in synapse formation. One is genetic, and involves the recruitment of highly specific neural cell adhesion molecules to the site of a tentative synaptic connection. These adhesion molecules, in lock-and-key fashion, form a physical but reversible glue-like bond between, say, a tentative synaptic projection from one GABA cell's axon and a receiving structure located across a tiny space on a neighboring cell body axon or dendritic filament emanating from another nerve cell. Last year, Huang's team became the first to observe how this process is regulated in living cortical circuits.

In their newly published research, they demonstrate in living basket cell interneurons – an important and prevalent subtype of GABA neuron – that a total blockade of GABA synthesis has no impact on the appearance of the many tentative synapses. "This state of preliminary contact appears to be the default state in these neurons," Huang says.

"GABA turns out to be a kind of discriminatory mechanism. As in speed-dating, in the end you want to form connections with the right partner. And you don't want to spend too much time or too much of your available resources checking each possibility out."

Interestingly, virtually all possibilities for matches -- in this case in terms of physical availability, i.e., proximity -- are seriously considered. GABA's surprising role is to serve as a trigger of the mechanism that swiftly eliminates incompatible contacts. Incompatibility in this context can mean biochemical or functional incongruity.

What is not yet understood, says Huang, is the nature of the pruning mechanism that GABA triggers. "There is some other signaling mechanism 'downstream,' so to speak, of GABA's triggering that performs the pruning. One possibility is that it is linked to GABA receptors. But we do not yet know."

Elucidating that detail is the next scientific objective of the team.

More information: "GABA Signaling Promotes Synapse Elimination and Axon Pruning in Developing Cortical Inhibitory Interneurons" appears January 4, 2012 in the Journal of Neuroscience. The authors are: Xiaoyun Wu, Yu Fu, Graham Knott, Jiangteng Lu, Graziella Di Cristo and Z. Josh Huang. The paper will be available online January 4 at DOI:10.1523/JNEUROSCI.3189-11.2012

 

Provided by Cold Spring Harbor Laboratory

"GABA signaling prunes back copious 'provisional' synapses during neural circuit assembly." January 3rd, 2012.http://medicalxpress.com/news/2012-01-gaba-prunes-copious-provisional-synapses.html

 

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THREE QUESTIONS TO ASK BEFORE UPDATING YOUR WEBPAGE

Looking to update your webpage in the New Year? Make sure not to waste time or money. Ask yourself these 3 important questions before you take any action.

INC suggests…

1. Who visits your website?

First, you need to know the profile of the people who visit your site. If your intended target market isn’t currently on the site, you’ll need to revisit your online marketing efforts. Knowing who is on the site will help reveal the mindsets of those visitors, and how your design can support their goals. Tailoring your website to their objectives might result in different paths from the home page, each serving content differentiated for user needs. For example, the Wells Fargo retirement website has three paths for exploring information based on your age range, and stage of saving toward retirement. Demographic information about your site visitors can also influence design decisions. If you serve an older demographic, for instance, the website should have options for increasing font size for easy reading.

2. What do your website visitors look for?

Many companies incorrectly optimize their websites for the content they have, rather than aligning their web content around what customers need. A classic case of this is automotive manufacturer websites. Consumers consistently want more information on future technologies, future vehicles not yet on the market, and car comparisons to older model years. But many automotive companies continue to plug only current model year content, leaving a large portion of site visitors dissatisfied. When setting your web strategy, find out what information online visitors are seeking—and then shape the content strategy around what users need.

3. Are they able to find it? If not, why?

Your site may offer the information users need but–if it’s poorly organized–they will never find it. In studies we’ve conducted at my digital research consultancy, AnswerLab, we found on average 30 percent to 40 percent of site visitors are unable to find all the information they’re seeking on a website. Common causes: poor navigation, unclear link names, site errors, and technical issues. Consumers don’t like to have to play around to uncover the information they need. Eliminating basic usability issues can increase online acquisition and retention efforts dramatically.

Get more information at INC!

Saving crops with rice genes

THE UNIVERSITY OF QUEENSLAND

The genes can offer plants resistance to bacterial and fungal pathogens - both of which are known to attack plants under stress. Image: mbbirdy/iStockphoto University of Queensland scientists have discovered that an ancient relative of rice contains genes that could potentially save food crops from the devastating effects of global warming. In a report, published in the "Proceedings of the National Academy of Sciences" (PNAS)*, it has been shown that wild rice plants in hotter and drier parts of Australia tend to be more genetically diverse. Professor Robert Henry from the Queensland Alliance for Agriculture and Food Innovation (QAAFI), who led the research team, said there were global implications for this discovery. "This finding will be useful in selecting crop varieties that can cope with a variable and changing climate," he said. The genetic diversity found by the scientists is seen as a bulwark against climate change because some genes offer plants a degree of resistance to bacterial and fungal pathogens, both of which are known to attack plants under stress. In a study conducted over more than 238 km of remote landscape, researchers from QAAFI and Southern Cross University compared wild cereal relatives growing in Australia with those found in the Fertile Crescent, where agriculture began in the cradle of civilisation. The Fertile Crescent is a geographical region that stretches more than 2000 km from the Nile in Egypt to the waters of the Persian Gulf in the west. Editor's Note: Original news release can be found here.

'Silver bullet' supplement could slow brain aging

Professor David Rollo and a group of researchers at McMaster may have found a "silver bullet" when it comes to slowing the aging of the brain.

The team's latest paper documents a new dietary supplement that completely maintains learning ability in older mice.

"These findings are not just significant, they're remarkable," says Rollo.

The tests were conducted by Vadim Aksenov, a PhD candidate in the Rollo laboratory in McMaster's Department of Biology.

A complex nutritional supplement containing 30 ingredients, including vitamins such as B1, C, D and E, along with beta-carotene, ginseng, green tea extract, cod liver oil and other acids and minerals, was used in the test. It was designed to offset five mechanisms associated with aging.

For mice aged 20-31 months (roughly equivalent to a 70-80-year-old human), those without the mixture in their diet showed no ability to learn new information. However, those who had taken the supplement displayed learning abilities equivalent to young mice, and more effectively completed the task.

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The trials focused on a region of the brain associated with Alzheimer's disease.

Other findings revealed that brain mass was increased by up to 10 per cent as a result of taking the supplement. The function of the cellular furnaces that provide brain energy (mitochondria) was also increased.

But what does it all mean for humans?

"This diet was our first try, so the door is just opening up," says Rollo. "Whether these results will translate to humans remains to be seen."

A major goal in anti-aging research involves the reduction of poisonous "free radicals" and their associated damage, while also maintaining mitochondrial function and energy supply later in life. The new supplement does both.

Unlike stand-alone vitamins, pills or anti-aging products, the combination of ingredients is far more effective in maintaining brain function.

While human testing has yet to begin, Rollo is hopeful that the supplement may one day slow the progression of Alzheimer's, Parkinson's and other neurodegenerative diseases in older adults.

If human trials prove safe and successful, most of the aging population could access the ingredients at local health food stores.

Jiangang Long, Jiankang Liu, Henry Szechtman, Parul Khanna and Sarthak Matravadia were also involved in the study.

Provided by McMaster University

"'Silver bullet' supplement could slow brain aging." January 4th, 2012. http://medicalxpress.com/news/2012-01-silver-bullet-supplement-brain-aging.html

 

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Robert Karl Stonjek

FIVE WAYS TO MAINTAIN YOUR ROLE AS LEADER

5 Ways To Free Yourself From A Leadership Rut

Leaders who are bored, in a rut, or otherwise find themselves anesthetized by the routine have a huge problem - they are not leading. Leadership is a game for the mentally agile, not the brain dead. Sound harsh? It’s meant to. While most of the world has succumbed to a static life imprisoned by the limitations of their own mind, real leaders are always looking beyond what is, thinking about the possibilities of what if, and acting to ensure what’s next. Why then do so many leaders complain about being in a rut? They get comfortable playing things safely, they rest on their laurels, they stop investing in personal growth and development, they settle, they quit and stay – they become a leader in title only. In the text that follows, I’ll share 5 tips guaranteed to jump-start your brain and get you off on the right foot for 2012.

All of us at one time or another experience the signs of boredom. Here’s the thing – boredom is a state of mind. The difference between real leaders, and leaders in title only, is what they do when the creative juices begin to dwindle. Feigned leaders accept the status quo, and real leaders see the signs of boredom as the precursor to needed change. For most people, the simple truth is excuses come easier than solutions – but who said leadership was easy?  Leadership is about acclimation and reacclimation, improvising and adapting, learning and unlearning – leadership is about change.

My observations and experiences over the years have led me to a very simple conclusion: I have yet to see anyone improve their status by maintaining the status quo. If you’re going to get comfortable with anything as a leader, I would suggest it be change. Change is a leaders best friend, and the one thing that will propel you forward. Don’t make excuses – make changes. Saying you don’t have time for “X” is just code for “ X” isn’t important to me. Saying you don’t have the resources needed for change is just an admission you’re not very resourceful. Leadership has little to do with resources, but everything to do with resourcefulness. The funny thing is, those who are the most resourceful often end-up with the greatest amount of resources. If you’re stuck in a leadership rut, the following 5 steps will help you find your path back to real leadership:

1. Go Break Something: Need to reinvigorate a stale mind or a less than thriving enterprise? Try changing the corporate landscape by shifting existing roles and responsibilities, or by bringing in fresh talent from the outside. If you want to drive innovation, lead change, and create growth, stir the pot – go break something. Slaughter a few sacred cows, challenge conventional wisdom, break a paradigm, and inject a little chaos into your ordered world. Old isn’t necessarily wrong, but likewise, it’s not necessarily right either. Overlay a new business model on top of the existing one, and look for ways to create new advantages and make needed improvements. Reengineer a best practice into a next practice. Ask yourself this question: Is the most tenured person in a particular position, the best person for the position? If not, make a change. Don’t be bored, just implement a little creative destruction.
2. Recharge Your Brain: A stagnant thought life is not a sign of healthy leadership. A brain is like any other energy source – it needs to be nourished in order to evolve. Whether you stimulate your brain through basic learning activities like reading, taking classes or participating in workshops or seminars, or by just giving it some well needed rest, the important thing is to make a concerted effort in this regard. Some of my best thinking comes when I remove myself from the routine of the office and go for a run. Vacations, sabbaticals, and service projects are also quite useful for creating new thinking paradigms. I’m a big proponent of attempting to carve out new neural pathways by subjecting the brain to new and creative ways of thinking. A few of the things I’m doing this year include going cold-turkey on television (a family project), playing one game of chess each day, and studying a new language. Change-up your routine and do things differently and more productively – you’ll be glad you did.
3. Get Some Help: Leading in isolation is dangerous. The best leaders surround themselves with wise counsel, and make a habit of seeking out sound advice. Start close to home – ask your family for their candid opinion of your shortcomings, and then listen. Those who love you the most will also give you the respect of candor. In addition to seeking guidance from your family, seek out professional advice and counsel by joining a peer group, hiring a coach, creating an advisory board, or finding a new mentor. There are abundant resources available to leaders resourceful enough to seek them out. Don’t allow yourself to be held hostage by your pride, ego, arrogance, or ignorance – go get some help.
4. Have a Vigorous Debate: Few things kindle the creative fires like a challenging debate. By seeking out dissenting views and differing opinions, you open your mind to new ideas and perspectives. A developed mind is the result of a challenged mind. Smart leaders take their business logic and willingly subject it brutal assault. In doing so, they often find what they believed to be close to perfect was in fact flawed. Go find the smartest people you can, and ask them to poke holes in your theories and beliefs. There is value in both validation and invalidation. Don’t be afraid of being proven wrong – be afraid of thinking you’re right when you’re not.
5. Fire Yourself: In the final analysis, if you can’t or won’t fix yourself, or you can’t or won’t allow yourself to be developed by others, then it’s time to pass the baton. Both you and your organization deserve more than just a leader in title, and if you cannot perform as leader then find someone who can. Whether you transition to a co-CEO role, entrepreneur in residence, Chairman of the Board, consultant, take a sabbatical, or you just resign your position, all concerned parties will be better off by making a move that is likely long overdue.

Egg shells reveal bird secrets

AARON FERNANDES, SCIENCENETWORK WA

"Eggshell has been largely overlooked as a substrate despite its impermeability and resistance to decay." Image: WillSelarep/iStockphoto WA researchers have found a breakthrough technique that uses eggshells from endangered and extinct birds as a molecular resource—revealing insights into the behaviour and evolutionary history of Australian feathered fauna. Murdoch University’s Dr James Haile says eggshell has been largely overlooked as a substrate despite its impermeability and resistance to decay, owing largely to the calcium carbonate matrix which acts to protect biomolecules. Dr Haile says researchers take the eggs of extinct and endangered birds and grind them down before sequencing the DNA to learn new information about these birds. “For extinct birds such as Madagascar’s elephant bird, we extract the DNA and compare that to living birds such as emu, cassowary, ostrich and others—from that we can see how those birds fit into the broader family tree and at what point they diverged,” Dr Haile says. “For the endangered birds, we take samples of abandoned eggshells and together with DNA samples from chicks and captive birds, develop a population database to get a picture of genetic diversity of the population.” Dr Haile says the application of his research can help to identify smuggled eggs coming into Australia and learn more about the behavior of Australia’s endangered birds for conservation strategies. He says it could even help determine the precise timing of the fragmentation of the supercontinent Gondwana. “For the endangered birds such as Australian megapodes and cockatoos, once you have a data base of genetic information, you can see who is related to who, what is the dispersal of their chicks? How many times a female has mated and if her partner dies will she find another?” Dr Haile says. “It’s a way of exploring the private lives of these birds.” “For the extinct birds, we know elephant birds were related to emus, cassowaries and others, but we aren’t sure how closely they were related because bones don’t preserve DNA very well due to the heat as well as being very rare. “Elephant bird eggs are the largest ever known, bigger than any dinosaur egg, and very resistant to decay so they’re an ideal but under research source of DNA.” Dr Haile says future research will improve enrichment techniques to concentrate endogenous DNA from contaminant DNA and will then use that in conjunction with second generation sequencing technologies, which produces up to a million DNA sequences from one sample. Editor's Note: Original news release can be found here.

Study finds drunken people aware of poor decisioins

A new study says that people who commit blunders while under the influence of alcohol know they're doing it; they just don't care.

This means buzzed or drunken people who engage in embarrassing or harmful behavior can't blame it on not having control, said researcher Bruce Bartholow, associate professor of psychology at the University of Missouri-Columbia.

While this isn't the first study that shows alcohol alters the behavior of those who consume it, "it's the first to show they don't care that they're making mistakes," said Bartholow, chief researcher on the study.

Brain tests during the study of 67 people in Columbia, Mo., showed that alcohol dulls a mechanism in the brain that tells an individual to put on the brakes when they realize they're making mistakes.

When the mechanism is working, "They slow down and try not to make the mistake again, or they take corrective action," Bartholow said.

Introduce alcohol and someone is more likely to disregard the moral stop sign, he said, even though they know what they're doing.

The study involved people between the ages of 21 and 35, students and nonstudents.

-Researchers gave a third of the participants drinks with enough alcohol to raise their blood levels to just under the legal driving limit of .08 percent, Bartholow said. They all got the same amount so researchers didn't measure if the effect was gradual.

-Researchers gave a third of the participants placebo drinks; they didn't know if the drinks contained alcohol.

-A third consumed drinks they knew contained no alcohol.

Then, the groups were given tasks designed to elicit mistakes. Researchers measured changes in participants' mood, their accuracy in computer tasks and how they perceived their accuracy in the tasks.

Bartholow said the researchers used devices on the participants to measure brain activity as the subjects took the tests. Medical technology exists to measure brain activity for impulse control, emotion, mood and other functions.

Nondrinkers had normal activity in the part of the brain that regulated recognizing mistakes. Drinkers had less activity, he said.

Nondrinkers who made mistakes slowed down and tried to correct the errors, he said. Drinkers made less of an effort or simply moved past their errors, the researcher said, even though they knew they'd made errors.

Researchers also interviewed participants after the tests, which helped affirm the findings in the computer tests, he said.

The dulling of the brain's mistake alarm only occurred among people who had alcoholic beverages, he said.

"Normally, someone who makes mistakes is aware and makes an effort not to make that mistake again," Bartholow said. The people in the alcohol group were less likely, however, to slow down and be more careful, but they realized they had made errors.

"Using alcohol doesn't allow someone to escape culpability," he said.

Dr. Douglas Schuerer, a trauma surgeon with Barnes-Jewish Hospital, said the findings aren't a surprise. "This says that people should think before they drink," he said.

That advice goes beyond New Year's Eve and its tradition of drinking: "It's something that needs to be considered 365," he said.

Many of Schuerer's patients are people from the hospital's emergency room who need surgery.

"About 50 percent of patients we see from traffic accidents, alcohol was involved," he said. "That doesn't always mean they were drinking; sometimes they were hit by a drunk driver."

In addition, he said he sees more personal injury accidents involving people impaired by alcohol.

The findings have a flip side, Bartholow said. A small amount of alcohol may help people with anxiety disorders or those who are hypersensitive to making errors, Bartholow said.

But he warns that "consistently drinking as a way to reduce anxiety can lead to serious problems, including alcoholism."

Bartholow's study, "Alcohol Effects on Performance Monitoring and Adjustment: Affect Modulation and Impairment of Evaluative Cognitive Control," has been accepted for publication in an upcoming edition of the Journal of Abnormal Psychology. The National Institute on Alcohol Abuse and Alcoholism and the University of Missouri Research Board paid for the study.

(c)2012 the St. Louis Post-Dispatch 
Distributed by MCT Information Services

"Study finds drunken people aware of poor decisioins." January 3rd, 2012. http://medicalxpress.com/news/2012-01-drunken-people-aware-poor-decisioins.html

 

Comment:
'Impairment of Evaluative Cognitive Control' is part of the brain control system, so those who claim not to have been in control when alcohol effected are being truthful and this study proves it.

Posted by
Robert Karl Stonjek