Posts tagged science
Articles and news from the latest research reports.
Computer Scientists Present Smile Database
What exactly happens to your face when you smile spontaneously, and how does that affect how old you look? Computer scientists from the University of Amsterdam’s (UvA) Faculty of Science recorded the smiles of hundreds of visitors to the NEMO science centre in Amsterdam, thus creating the most comprehensive smile database ever. The results can be seen via the link below. The research was conducted as part of the project Science Live, sponsored by the Netherlands Organisation for Scientific Research (NOW) and the Royal Netherlands Academy of Arts and Sciences (KNAW).
Smile Database: http://www.uva-nemo.org/
Grin and bear it — smiling facilitates stress recovery
In a study forthcoming in Psychological Science, a journal of the Association for Psychological Science, psychological scientists Tara Kraft and Sarah Pressman of the University of Kansas investigate the potential benefits of smiling by looking at how different types of smiling, and the awareness of smiling, affects individuals’ ability to recover from episodes of stress.
"Age old adages, such as ‘grin and bear it’ have suggested smiling to be not only an important nonverbal indicator of happiness but also wishfully promotes smiling as a panacea for life’s stressful events," says Kraft. "We wanted to examine whether these adages had scientific merit; whether smiling could have real health-relevant benefits."
Brain development is delayed in attention-deficit/hyperactivity disorder
July 30, 2012
Is attention-deficit/hyperactivity disorder (ADHD) due to a delay in brain development or the result of complete deviation from typical development? In the current issue of Biological Psychiatry, Dr. Philip Shaw and colleagues present evidence for delay based on a study by the National Institutes of Health.
The cerebral cortex is the folded gray tissue that makes up the outermost portion of the brain, covering the brain’s inner structures. This tissue has left and right hemispheres and is divided into lobes. Each lobe performs specific and vitally important functions, including attention, thought, language, and sensory processing.
Two dimensions of this structure are cortical thickness and cortical surface area, both of which mature during childhood as part of the normal developmental process. This group of scientists had previously found that the thickening process is delayed in children diagnosed with ADHD. So in this study, they set out to measure whether surface area development is similarly delayed.
They recruited 234 children with ADHD and 231 typically developing children and scanned each up to 4 times. The first scan was taken at about age 10, and the final scan was around age 17. Using advanced neuroimaging technology, they were able to map the trajectories of surface area development at over 80,000 points across the brain.
They found that the development of the cortical surface is delayed in frontal brain regions in children with ADHD. For example, the typically developing children attained 50% peak area in the right prefrontal cortex at a mean age of 12.7 years, whereas the ADHD children didn’t reach this peak until 14.6 years of age.
"As other components of cortical development are also delayed, this suggests there is a global delay in ADHD in brain regions important for the control of action and attention," said Dr. Shaw, a clinician studying ADHD at the National Institute of Mental Health and first author of this study.
"These data highlight the importance of longitudinal approaches to brain structure," commented Dr. John Krystal, Editor of Biological Psychiatry. "Seeing a lag in brain development, we now need to try to understand the causes of this developmental delay in ADHD."
Dr Shaw agrees, adding that this finding “guides us to search for genes that control the timing of brain development in the disorder, opening up new targets for treatment.”
Additional work expanding these measures into adulthood will also be important. Such data would help determine whether or when a degree of normalization occurs, or if these delays translate into long-lasting cortical deficits.
Provided by Elsevier
Source: medicalxpress.com
What Pleasure Looks Like in Babies, Primates and Rats
To decipher the brain circuits that underlie pleasure, neuroscientists often have to assess liking and disliking in nonverbal creatures. They do it by monitoring facial expressions and head and arm movements, such as those depicted in the video here. Licking the lips, for instance, indicates a food tasted delicious to in infant, whereas turning the head from side to side indicates “yuk.” In the video, the term “hedonic reactions” refers to pleasure.
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.
Neuroscientist keeps astronauts awake with ISS lighting tweaks
A neuroscientist is working with Nasa to develop special lamps that could help restore the circadian rhythm of exhausted astronauts working aboard the International Space Station (ISS).
Thomas Jefferson University neuroscientist George C Brainard, who has headed up the university’s Light Research Program since 1984, received approval for the lights in early 2012 and 100 of the LED models are due to be sent to Nasa by mid-2015. The lights have three different colour temperatures to help ease the astronauts into morning, nighttime and normal working mode.
"An astronaut here on Earth experiences a 24-hour day/night cycle just like you and I," explained Brainard. "Now when they’re on the space station, they’re circling the planet every 90 minutes. So they’ve gone from a 24-hour day to a 90-minute day."
New link found between MS treatment and vitamin D
July 30, 2012
(Medical Xpress) — A new study by researchers at the Menzies Research Institute Tasmania (Menzies) suggests that one of the main treatments for multiple sclerosis (MS) may also increase the amount of vitamin D patients receive from sun exposure.
More people suffer with MS per capita in Tasmania than in any other state in Australia. There is currently no cure, but treatments are available to ease some of the symptoms.
This observational study published in the prestigious journal Neurology found that patients taking one of the most common treatments for MS, interferon-beta, had higher vitamin D levels than those not on this treatment or those using other forms of treatment for MS.
Around 60 per cent of MS patients with the relapsing-remitting form of MS are treated with interferon-beta. It is derived from a naturally-occurring component of the human immune system and has been found to reduce the frequency of relapse and other specific symptoms of MS.
Despite being a front-line treatment in MS, how interferon-beta actually works in MS is unclear, though it is thought to act by affecting the immune system.
The study used data from the MS Longitudinal Study, from 2002-2005, and this analysis used data from 178 persons with MS living in southern Tasmania.
Menzies researchers Dr. Niall Stewart and Dr. Steve Simpson, Jr. were co-first authors on the paper. Dr. Simpson says the findings suggest that part of the therapeutic effects of interferon-beta on relapse in MS may be through its effects on vitamin D, since vitamin D has the ability to reduce inflammatory pathways in the immune system.
“Not only did we find that persons taking interferon-beta had higher vitamin D levels than those not taking it, we also found that this increase in vitamin D was due to an enhancement of the association between sun and vitamin D, with persons on interferon-beta having nearly three-times as much vitamin D from similar amounts of sun exposure to those not taking interferon-beta,” Dr. Simpson said.
“We have previously shown persons with MS with higher vitamin D levels had lower numbers of relapses. In this analysis, however, we found that vitamin D was only associated with reduced risk of relapse among those using interferon-beta.
“Interestingly, the reciprocal was also true, with interferon-beta only associated with reduced risk of relapse among those with higher levels of vitamin D,” Dr. Simpson said.
Senior author, Professor Bruce Taylor, says the new findings have the potential to markedly affect clinical practice in the treatment of MS, but cautions that more research is required.
“This study adds to the growing body of research into MS, but before we can apply these findings to MS treatment practice, clinical trials must be done to prove these associations. Menzies is planning to undertake such a trial in the future,” Professor Taylor said.
“This study does provide further support for persons with MS to periodically have their vitamin D measured, particularly in winter, and if they are deficient, to seek the advice of their physician as to whether supplementation is appropriate for them.”
Provided by University of Tasmania
Source: medicalxpress.com
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.