Posts tagged brain
Articles and news from the latest research reports.
Your Body Influences Your Preferences
By Matthew Hutson | July 30, 2012
Why we are biased toward things on our dominant side
Image: GETTY IMAGES
If you are right-handed, chances are you will make different choices than your left-handed friends. A series of recent studies shows that we associate our dominant side with good and our nondominant side with bad, preferring products and people that happen to be on our “good” side over those closer to the other half of our body.
The theory of embodied cognition, widely embraced by cognitive scientists in recent years, holds that our abstract ideas are grounded in our physical experiences in the world. (See above: “embraced,” “holds,” “grounded.”) Daniel Casasanto, a psychologist at the New School for Social Research, began to wonder: If our bodies shape our thinking, do people with different bodies think differently? He has been using handedness as a test bed for this body-specific hypothesis.
In a set of studies published in 2009 Casasanto found that right-handers associate right with good and left with bad and that left-handers make the reverse associations. People prefer objects, job candidates and images of alien creatures on their dominant side to those on their nondominant side. In 2010 he reported that presidential candidates (Kerry, Bush, Obama and McCain) gesture with their dominant hands when making positive points and their weak hands to emphasize darker matters. And he has collected data to suggest that lefties hold higher opinions of their flight attendants when seated on the right side of a plane.
To rule out the possibility that this bias is purely genetic, like handedness is, Casasanto handicapped people’s preferred hands. In a 2011 study he had subjects manipulate dominoes while wearing a bulky ski glove on their good hand. Afterward, they showed a bias against things on that side. The results suggest that we look kindly on half the world because we can interact with that side fluently. Make it a hassle, and opinions flip.
Most recently, Casasanto reported in January in Cognitive Science that children as young as six display a handedness bias. Kids were asked which animal in a series of cartoon pairs looked nicer or smarter. The right-handers more often chose the drawing on the right side, and the left-handers more often chose the animal on the left. They also elected to put away their preferred toys in boxes on their dominant side.
“We all walk around with these lopsided bodies and have to interact with our environment in systematically different ways,” Casasanto notes. Given how broadly those interactions can influence our thinking, he says, “body specificity may be shaping our judgments in the real world in ways that we never suspected.”
Source: Scientific American
When rules change, brain falters
For the human brain, learning a new task when rules change can be a surprisingly difficult process marred by repeated mistakes, according to a new study by Michigan State University psychology researchers.
Imagine traveling to Ireland and suddenly having to drive on the left side of the road. The brain, trained for right-side driving, becomes overburdened trying to suppress the old rules while simultaneously focusing on the new rules, said Hans Schroder, primary researcher on the study.
A better judge of character with oxytocin nasal spray?
In other contexts, oxytocin is already well-known as the “bliss hormone”. The hormone is secreted upon stimulation by touch and is known to result in a feeling of calm and physical relaxation. It is also used to induce labour in childbirth and as an aid for women experiencing difficulties in breastfeeding.
Oxytocin has also been referred to as a “mindreading” hormone. Recent research findings show that there may be some truth to these claims – although the mindreading component may have a more down-to-earth explanation.
Smell the potassium: Surprising find in study of sex- and aggression-triggering vomeronasal organ
"We found two new ion channels—both of them potassium channels—through which VNO neurons are activated in mice," says Associate Investigator C. Ron Yu, Ph.D., senior author of the study. "This is quite unusual; potassium channels normally don’t play a direct role in the activation of sensory neurons."
Humans have shrunken, seemingly vestigial VNOs, but still exhibit instinctive, pre-programmed behaviors relating to reproduction and aggression. Scientists hope that an understanding of how the VNO works in mice and other lower mammals will provide clues to how these innate behaviors are triggered in humans.
The VNO works in much the same way as the main olfactory organ that provides the sense of smell. Its neurons and their input stalks, known as dendrites, are studded with specialized receptors that can be activated by contact with specific messenger-chemicals called pheromones, found mostly in body fluids. When activated, VNO receptors cause adjacent ion channels to open or close allowing ions to flood into or out of a neuron. These inflows and outflows of electric charge create voltage surges that can activate a VNO neuron, so that it signals to the brain to turn on a specific behavior.
Science of Eyewitness Memory Enters Courtroom
Science has prevailed over injustice in the state of New Jersey, where all jurors will soon learn about memory’s unreliability and the limits of eyewitness testimony.
According to instructions issued July 19 by New Jersey’s Supreme Court, judges must tell jurors that “human memory is not foolproof,” and enumerate the many ways in which eyewitness recall can be distorted or mistaken.
Can bacteria fight brain cancer?
The thinking behind an approach that has caused trouble in California.
Last week, the Sacramento Bee reported that two neurosurgeons at the University of California, Davis, had been banned from research on humans after deliberately infecting three terminally ill cancer patients with pathogenic bacteria in an attempt to treat them. All three died, two showing complications from the infection. Nature explores what happened and the science behind it.
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.
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.”