Published: February 9, 2012
Image: by Chris Inside Flickr
With no lab tests to guide the clinician, psychiatric diagnostics is challenging and controversial. Antisocial personality disorder is defined as “a pervasive pattern of disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood,” according to the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) of the American Psychiatric Association.
DSM-IV provides formal diagnostic criteria for every psychiatric disorder. This process may be guided by rating scales that measure the traits and features associated with a personality disorder. But, until now, no one has studied the dimensional structure associated with the DSM antisocial personality disorder criteria.
Dr. Kenneth Kendler of Virginia Commonwealth University and colleagues examined questionnaire and genetic data from adult twins. They found that the DSM-IV criteria do not reflect a single dimension of liability but rather are influenced by two dimensions of genetic risk reflecting aggressive-disregard and disinhibition.
“When psychiatrists, as clinicians or researchers, think about our psychiatric disorders, we tend to think of them as one thing – one kind of disorder – a reflection of one underlying dimension of liability,” said Dr. Kendler. “This is also true of genetics researchers. We tend to want to identify and then detect ‘the’ risk genes underlying disorder X or Y.”
Kendler added, “What is most interesting about the results of this paper is that they falsify this inherent and rather deeply held assumption. Genetic risk factors for antisocial personality disorder are not one thing. Rather, the disorder, as conceptualized by DSM-IV, reflects two distinct genetic dimensions of risk.” [continue reading…]
Published: February 8, 2012
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hy are older drivers, especially those over 70, involved in crashes primarily at intersections? You may tend to attribute this to cognitive or physical decline, such as slower reaction time or poor sight. These factors are undoubtedly part of the problem; however new research by some University of Massachusetts Amherst researchers have come up with another explanation – older drivers acquire bad habits, and those habits can be unlearned. “The effectiveness of our training program indicates that at least a major part of older drivers’ problems can be remediated,” says psychologist Alexander Pollatsek, who authored the article with Mathew R. E. Romoser, and Donald L. Fisher after analyzing two earlier studies. “A large percentage of not attending [to the hazards at intersections] is due to some strategy or mindset they’ve gotten into, rather than some problem with the brain,” he continues. “It’s a software problem, not a hardware problem.” The findings appear in
Current Directions in Psychological Science, a journal of the
Association for Psychological Science.
In the first study, older drivers (over 70) were compared with younger experienced drivers (25 to 55) who were both navigating an actual vehicle through a simulated world projected on displays outside the vehicle. Drivers approached three different intersections and had to turn. In one, a hill across the main street intersection obscured a possibly approaching car. In the others—turning from a side street onto a main street or vice-versa—trees and curves blocked views of other oncoming cars. The older drivers scanned the danger zone (the region from which a plausible threat could emerge) less often and for significantly shorter times both while approaching and completing the turn —compromising safety. [continue reading…]
Published: February 3, 2012
Today’s Guardian reports that tweeting or checking emails may be harder to resist than cigarettes and alcohol, according to researchers who tried to measure how well people could resist their desires.
They even claim that while sleep and sex may be stronger urges, people are more likely to give in to longings or cravings to use social and other media.They even claim that while sleep and sex may be stronger urges, people are more likely to give in to longings or cravings to use social and other media.
A team headed by Wilhelm Hofmann of Chicago University’s Booth Business School say their experiment, using BlackBerrys, to gauge the willpower of 205 people aged between 18 and 85 in and around the German city of Würtzburg is the first to monitor such responses “in the wild” outside a laboratory.
The results will soon be published in the journal Psychological Science. Read the full story in The Guardian
Published: February 3, 2012
Image: StockXpert
lacebos reduce pain by creating an expectation of relief. Distraction—say, doing a puzzle—relieves it by keeping the brain busy. But do they use the same brain processes? Neuromaging suggests they do. When applying a placebo, scientists see activity in the dorsolateral prefrontal cortex. That’s the part of the brain that controls high-level cognitive functions like working memory and attention—which is what you use to do that distracting puzzle.
Now a new study challenges the theory that the placebo effect is a high-level cognitive function. The authors—Jason T. Buhle, Bradford L. Stevens, and Jonathan J. Friedman of Columbia University and Tor D. Wager of the University of Colorado Boulder—reduced pain in two ways – either by giving them a placebo, or a difficult memory task. lacebo. But when they put the two together, “the level of pain reduction that people experienced added up. There was no interference between them,” says Buhle. “That suggests they rely on separate mechanisms.” The findings, published in Psychological Science, a journal of the Association for Psychological Science, could help clinicians maximize pain relief without drugs. [continue reading…]
