Posted by
puddle
at
9/14/2007 06:49:00 pm
0
comments
Do I dare to eat a peach?
Posted by
puddle
at
9/13/2007 01:45:00 am
0
comments
Posted by
puddle
at
9/11/2007 04:17:00 pm
0
comments
by Marlowe HoodSun Sep 9, 1:33 PM ET
The brain neurons of liberals and conservatives fire differently when confronted with tough choices, suggesting that some political divides may be hard-wired, according a study released Sunday.
Aristotle may have been more on the mark than he realised when he said that man is by nature a political animal.
Dozens of previous studies have established a strong link between political persuasion and certain personality traits.
Conservatives tend to crave order and structure in their lives, and are more consistent in the way they make decisions. Liberals, by contrast, show a higher tolerance for ambiguity and complexity, and adapt more easily to unexpected circumstances.
The affinity between political views and "cognitive style" has also been shown to be heritable, handed down from parents to children, said the study, published in the British journal Nature Neuroscience.
Intrigued by these correlations, New York University political scientist David Amodio and colleagues decided to find out if the brains of liberals and conservatives reacted differently to the same stimuli.
A group of 43 right-handed subjects were asked to perform a series of computer tests designed to evaluate their unrehearsed response to cues urging them to break a well-established routine.
"People often drive home from work on the same route, day after day, such that it becomes habitual and doesn't involve much thinking," Amodio explained by way of comparison in an e-mail.
"But occasionally there is road work, or perhaps an animal crosses the road, and you need to break out of your habitual response in order to deal with this new information."
Using electroencephalographs, which measure neuronal impulses, the researchers examined activity in a part of the brain -- the anterior cingulate cortex -- that is strongly linked with the self-regulatory process of conflict monitoring.
The match-up was unmistakable: respondents who had described themselves as liberals showed "significantly greater conflict-related neural activity" when the hypothetical situation called for an unscheduled break in routine.
Conservatives, however, were less flexible, refusing to deviate from old habits "despite signals that this ... should be changed."
Whether that is good or bad, of course, depends on one's perspective: one could interpret the results to mean that liberals are nimble-minded and conservatives rigid and stubborn.
Or one could, with equal justice, conclude that wishy-washy liberals don't stick to their guns, while conservatives and steadfast and loyal.
As to the more intriguing question of which comes first, the patterns in neuron activity or the political orientation, Amodio is reluctant to hazard a guess.
"The neural mechanisms for conflict monitoring are formed early in childhood," and are probably rooted in part in our genetic heritage, he said.
"But even if genes may provide a blueprint for more liberal or conservative orientations, they are shaped substantially by one's environment over the course of development," he added.
Obscuring causal links even more is the fact that the brain is malleable and neural functions can change as a result of new experiences.
Posted by
puddle
at
9/10/2007 11:39:00 pm
0
comments
Posted by
puddle
at
9/08/2007 08:47:00 pm
0
comments
Posted by
puddle
at
9/07/2007 07:18:00 am
6
comments
PHILADELPHIA - Obesity and aversion to exercise have become hallmarks of modern society - and a new study suggests that a blood protein linked to these lifestyle factors may be an indicator for an increased risk of developing pancreatic cancer. Researchers from the Dana Farber Cancer Institute report their findings in the August 15 issue of Cancer Research, a journal of the American Association for Cancer Research.
In a study of 144 patients with pancreatic cancer and 429 people without the disease, a subset of patients with low blood levels of a protein called IGFBP-1 were at approximately twice the risk of developing pancreatic cancer. Low blood levels of this protein have previously been linked to excess weight and lack of physical activity. Their data originated from tens of thousands of men and women enrolled in four large-scale cohort studies - the Health Professionals Follow-Up Study, the Nurses' Health Study, the Physicians' Health Study and the Women's Health Initiative Observational Study - all of which followed the health of participants over numerous years.
"The prognosis for many patients with pancreatic cancer remains poor, so it is vitally important that we indentify and better understand risk factors for the disease, particularly risk factors that are modifiable" said lead study author, Brian M. Wolpin, M.D., attending physician at Dana Farber Cancer Institute. "In addition to cigarette smoking, exercise and weight control appear to be important modifiable risk factors for this difficult disease."
Pancreatic cancer is one of the leading causes of cancer death in America - over 33,000 Americans will likely die from the disease in 2007, according to projections from the American Cancer Society. Studies indicate that smoking is responsible for about 25 percent of pancreatic cancer cases, and obesity and lack of exercise may account for a similar amount, Dr. Wolpin said.
According to Dr. Wolpin, previous research has linked IGFBP-1 (insulin-like growth factor binding protein one) with increased risk of colorectal and endometrial cancer. Like its name suggests, IGFBP-1 is a molecule that binds with insulin-like growth factor (IGF), a hormone normally associated with growth and development. In the laboratory, IGF has been noted to increase the growth of pancreatic cancer cells. Since one role of IGFBP-1 is to sequester IGF, Dr. Wolpin and his colleagues were interested as to whether people who developed pancreatic cancer had lower blood levels of the IGFBP-1 protein.
To study the relationship between IGFBP-1 and pancreatic cancer, Dr. Wolpin and his colleagues chose pancreatic cancer patients enrolled in one of the four cohort studies and with blood drawn four or more years before developing cancer. The blood levels of IGFBP-1 from these patients were compared to those taken from 429 cancer-free people also enrolled in one of the cohort studies. According to their findings, patients with low blood levels of IGFBP-1 were nearly twice as likely to develop pancreatic cancer.
"We still have much to learn about the mechanisms by which obesity and sedentary lifestyle may contribute to the risk of pancreatic cancer," Dr. Wolpin said. "While it is too early to discuss IGFBP-1 as a suitable blood marker for pancreatic cancer, it is never too early to address the lifestyle issues that may contribute to low levels of IGFBP-1 and to an elevated risk of this difficult disease."
The study was supported by The Lustgarten Foundation for Pancreatic Cancer Research and the National Cancer Institute.
Posted by
puddle
at
9/07/2007 01:12:00 am
3
comments
Posted by
puddle
at
9/03/2007 11:57:00 pm
0
comments
Posted by
puddle
at
8/30/2007 09:24:00 pm
0
comments