Posts tagged neuroscience
Articles and news from the latest research reports.
Fear study reveals mental processes
July 25, 2012
A University study has shown how our minds unconsciously respond to threats.
Researchers studying how our minds develop fears in response to danger found that people can quickly learn to recognise a threat even when they are unaware of it.
However, they also found that this learning is swiftly forgotten. In contrast, when people are aware of the threat, they take longer to learn to be afraid of it, but retain the fear in the long term.
Scientists from the University of Edinburgh and New York University, who carried out the study, say the finding may be a key insight into the differences between conscious and nonconscious mental processes.
Fear study
Researchers measured physiological fear responses - the amount of sweat on the fingertips - in groups of people who looked at pictures and were given mild electric shocks whenever one of these pictures was shown.
All the people who participated in the study saw the pictures with just one eye. But whereas some of them were allowed to see the pictures clearly, the researchers suppressed the pictures from other subjects’ awareness by showing colourful, dynamic images to the other eye.
The study found that subjects who were prevented from consciously seeing the pictures learned to be afraid of the image associated with a shock more quickly than those who were allowed to see them without suppression.
However, these subjects quickly forgot this association between the images and the electric shocks as the experiment continued.
In contrast, those subjects who were allowed to see the image clearly formed a stronger association over time.
How the brain reacts to threats is key to understanding how human beings function. This study shows that we are capable of learning very rapidly that something is a threat even when we don’t perceive it consciously. Such learning, however, is fleeting.
-David Carmel, Researcher, Department of Psychology
Source: The University of Edinburgh
What links Alzheimer’s disease, the bridges of Königsberg and Twitter?
A mathematical puzzle originating in 18th century Prussia has led to insights in fields as diverse as banking, social networking, epidemiology – and now Alzheimer’s disease
The progression of Alzheimer’s is accompanied by a buildup in the brain of amyloid plaque and the breakdown of communication between nerve cells. Recent research suggests that graph theory can provide fascinating insights into the faulty wiring behind the progressive memory loss of Alzheimer’s. But what exactly is graph theory?
To discover the origins of the theory we have to go back to the 18th century and the ancient Prussian city of Königsberg, now Kaliningrad – that tiny city state wedged between Poland and Lithuania. It was here that Leonard Euler solved the long-standing Bridges of Königsberg Problem, which has had a profound effect on the development of network theory.
The Internet global network is a phenomenon of technological civilization, and its exceptional complexity surpasses anything mankind has ever created. In essence, what we are dealing with here is a huge quantity of utterly unstructured information. The Internet map is an attempt to look into the hidden structure of the network, fathom its colossal scale, and examine that which is impossible to understand from the bare figures of statistics.
Opinion: Scientists’ Intuitive Failures
Much of what researchers believe about the public and effective communication is wrong.
Scientists in the United States and Europe have long been concerned with how well the public understands science, whether or not the media adequately covers science, and how the public reaches decisions on complex science-related policy issues. Given the norms of our profession, however, it is ironic that many of these debates about how to best communicate science with lay populations are driven by intuitive assumptions on the part of scientists rather than the growing body of social science research on the topic that has developed over the past 2 decades.
In May, more than 500 researchers, journalists, and policy professionals gathered at the National Academies in Washington, DC, for a 2-day forum on the “Science of Science Communication” to dispel some of these intuitive but persistent myths about science, the media, and the public.
1. Americans no longer trust scientists. Prominent scientists warn that we have entered a new “dark age,” where the public no longer trusts scientific expertise.
2. Science journalism is dead. Though scientists are often critical of the news media, calling attention to perceived bias on the part of journalists, they also fear that budget cuts at news organizations have meant the death of science journalism.
3. Entertainment media promote a culture of anti-science. Since the 1970s, scientists have feared that entertainment TV and film undermine public trust in science.
4. The problem is the public, not scientists or policymakers. Scientists have long believed that when the public disagreed with them on matters of policy, public ignorance was to blame.
5. Political views don’t influence the judgments of scientists. In debating science-related policy matters, we tend to assume that scientists are not influenced by their own political views. Yet in a recent study co-authored by one of us (Scheufele), we find that even after controlling for their scientific judgments, scientists’ political ideologies significantly influence their preferences for potential regulatory policies.
Science fiction comes to life in Italian lab
At Italy’s Sant’Anna university, a bionic arm commanded by the human brain or a limb extension that allows rescuers to lift rubble after earthquakes are just some of the futuristic innovations in the pipeline.
“The idea is to get robots out of factories where they have shown their worth and to transform them into household machines which can live together with humans,” says Professor Paolo Dario, director of the college’s bio-robotics department.
The university in the historic town of Pisa in Tuscany is a veritable factory of ideas.
Researchers here are working on projects ranging from a robot that can come to your door to collect your recycling to tomatoes that slow the effects of ageing and plants that survive underwater to help flood-prone regions of the world.
Think You’re a Comic Genius? Maybe You’re Just Overconfident
No matter how badly the joke is told, it will sometimes elicit a few polite laughs.
Why?
Because social norms make us averse to providing negative feedback, says Joyce Ehrlinger, a Florida State University assistant professor of psychology whose latest laboratory research recreated everyday interactions in which people might feel pressured to withhold negative information.
A Neurologist Makes the Case for Teaching Teachers About the Brain
Do you recall some of your college professors who knew their subject matter but had zero teaching skills? Staying awake in their one-way-directed lecture classes required Herculean strength (or lots of coffee). They were never trained to develop the skillset of engagement strategies.
Even though I was a physician with a strong science background, when I decided to become a classroom teacher (and thought I’d teach science), I did not want to make that career change without the benefit of instruction and guided student teaching. The year I spent in my graduate school of education program was invaluable in my transition to becoming a professional educator.
Did Your Brain Make You Do It?
ARE you responsible for your behavior if your brain “made you do it”?
Often we think not. For example, research now suggests that the brain’s frontal lobes, which are crucial for self-control, are not yet mature in adolescents. This finding has helped shape attitudes about whether young people are fully responsible for their actions. In 2005, when the Supreme Court ruled that the death penalty for juveniles was unconstitutional, its decision explicitly took into consideration that “parts of the brain involved in behavior control continue to mature through late adolescence.”
Building a human on a chip, organ by organ
Human “organs on chips” could be linked to make the ideal guinea pig, revolutionising the way drugs are tested and cancer is treated
Such organs on chips can be used to model how human organs function and respond to drugs, says Ingber. He thinks that they even have the potential to eliminate the use of animals in drug testing. “Animal testing is expensive and time-consuming, and animals are not always representative of humans.”
Still, Ingber points out that the chips can perform some roles that animal studies cannot. For instance, they could be personalised by building them from an individual’s own cells. In theory, a doctor could send tissue samples to a lab to test a potentially harmful therapy on such a chip before handing out a prescription. This would be especially useful for people with cancer, as the various therapies available can have very different effects on different people, Ingber says. “You could get a quick yes-or-no answer to whether a drug would work or not,” he says.
Personalised chips might also speed up clinical trials. “Someday it might be possible to shortcut clinical trials by using chips containing cells from different human populations that are known to respond differently to specific drug classes,” Ingber says.
Stress May Cause Women’s Brains to Age Earlier
By Makini Brice | July 26, 2012
Scientists were surprised, expecting the areas of the brain to age more slowly, or even delayed, than those of men.
Photo: Microsoft
Even though the gap is closing now in many high-income countries, on average, women tend to live longer lives than men do. Despite – or perhaps because of – women’s physical longevity, women tend to battle cognitive decline in much greater numbers than men do. In fact, women are more likely to suffer from various types of dementia, including the much-maligned Alzheimer’s disease. Now researchers think that they have an answer to the cause of this double-edged sword: stress. Specifically, stress ages women’s brains more quickly than it does men.
Scientists, and every-day observers, have noted that some body parts age at different rates than others do. As people become older, some genes become more active while others become less so. These changes in activity can be monitored through a “transcriptome,” which collects data on all the RNA – the transcripts that carry DNA’s instructions to cells. A multinational team from Australia, China, Germany, and the United States set out to analyze the transcriptomes for 55 different men and women of various ages.
The researchers were fascinated by what they found. According to the abstract of their article published in Aging Cell, “In the superior frontal gyrus (SFG), a part of the prefrontal cortex, we observed manifest differences between the two sexes in the timing of age-related changes, i.e.sexual heterochrony. Intriguingly, age-related expression changes predominantly occurred earlier, or at a faster pace, in females compared to males. These changes included decreased energy production and neural function, and up-regulation of the immune response, all major features of brain aging.”
In other words, researchers found that the brains of women aged more quickly than those of men, especially in the prefrontal cortex. Scientists were surprised, expecting the areas of the brain to age more slowly, or even delayed, than those of men.
In the superior frontal gyrus, researchers found 667 genes that were expressed differently by gender during the aging process. Within that number, 98 percent were associated with faster aging in women.
Scientists were not convinced that the reason lay in biological differences. In fact, since only half of women displayed accelerated aging, they were convinced that the difference was environmental. Researchers theorize that stress is the difference-maker, and that it affects women’s brains more severely than it does men. While a researcher unaffiliated with the study said that the difference could also be caused by inflammation,
Mehmet Somel and his team have conducted similar research on monkeys that confirms their stress theory.
Source: Medical Daily