Showing posts with label research. Show all posts
Showing posts with label research. Show all posts

Tuesday, March 01, 2011

Why Guinness really is the black stuff. Scientists say stout makes you bitter

The adverts always said Guinness is good for you. But it may be that drinking the black stuff makes you bitter as well as better.

In an intriguing study, scientists have linked tart tastes with an unforgiving  mind.

And the more conservative a person’s views, the more their thoughts are  affected by their tastebuds.

The findings suggest that drinks such as stout, bitter and gin and tonic should be  drunk carefully among friends

Read more . . .

Tuesday, February 08, 2011

Depression: Here's a gene that may make some folks more susceptible

Depression strikes a huge number of Americans at one time or another of their lives -- and studies show that genes are involved in susceptibility to this awful “Black Dog,” as Winston Churchill used to term his struggle with the mood disorder.

But what are the genes involved? A study in the journal Archives of General Psychiatry implicates one. It directs the formation of a small peptide in our brains, Neuropeptide Y.

Neuropeptide Y is found all over the place in our brains, and prior studies had shown that the levels in our bloodstreams and spinal fluid seem to correlate with how resilient we are to life’s stresses: the more NPY, the more resilient.

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Sunday, October 17, 2010

Yale University researchers find key genetic trigger of depression

Yale University researchers have found a gene that seems to be a key contributor to the onset of depression and is a promising target for a new class of antidepressants, they report Oct. 17 in the journal Nature Medicine.

"This could be a primary cause, or at least a major contributing factor, to the signaling abnormalities that lead to depression," said Ronald S. Duman, professor of psychiatry and pharmacology at Yale and senior author of the study.

Read more . . .

This is pretty big news.  I am hoping they find better ways to deal with depression soon.

Wednesday, August 08, 2007

Low-Cal Sweets Might Still Make Kids Obese

WEDNESDAY, Aug. 8 (HealthDay News) -- Diet foods and drinks meant to help children control their weight may actually spur overeating and obesity, Canadian researchers say.

The study found that animals learn to associate the taste of food with the amount of caloric energy it provides. The researchers speculate that children who eat low-calorie versions of foods that normally have a high calorie content may develop distorted connections between taste and calorie content, resulting in overeating as the children grow up.

"The use of diet food and drinks from an early age into adulthood may induce overeating and gradual weight gain through the taste conditioning process that we have described," lead author and sociologist Dr. David Pierce, of the University of Alberta, said in a prepared statement.

In a series of experiments published Aug. 8 in the journal Obesity, the researchers found that young rats started to overeat when they received low-calorie food and drink. Adolescent rats did not overeat when given low-calorie items.

This may be because, unlike the younger rats, the adolescent rats didn't rely on taste-related cues to assess the caloric energy content of their food, the researchers said.

"Based on what we've learned, it is better for children to eat healthy, well-balanced diets with sufficient calories for their daily activities rather than low-calorie snacks or meals," Pierce said.

[source]

Thursday, July 19, 2007

Weight bias may harm obese children

NEW YORK (Reuters Health) - The stigma that society attaches to obesity can cause children immediate, and possibly lasting, harm, according to a research review.

Overweight children and teens are commonly teased or ostracized by their peers, and sometimes treated differently by teachers and even parents. This, the review shows, can lead to low self-esteem, poor school performance, avoidance of physical activity and, in the most serious cases, depression and suicide.

Research has long demonstrated the weight bias that heavy children face. In a classic 1961 study, 640 subjects between 10 and 11 years old were shown six pictures of other children their age: one child was overweight; one was normal-weight; and four had some form of physical disability.

When the study participants were asked to rank the children in the order of whom they would like to be friends with, they ranked the overweight child last.

Read more . . .



Monday, March 26, 2007

How The Brain Rewires Itself

article from TIME

It was a fairly modest experiment, as these things go, with volunteers trooping into the lab at Harvard Medical School to learn and practice a little five-finger piano exercise. Neuroscientist Alvaro Pascual-Leone instructed the members of one group to play as fluidly as they could, trying to keep to the metronome's 60 beats per minute. Every day for five days, the volunteers practiced for two hours. Then they took a test.

At the end of each day's practice session, they sat beneath a coil of wire that sent a brief magnetic pulse into the motor cortex of their brain, located in a strip running from the crown of the head toward each ear. The so-called transcranial-magnetic-stimulation (TMS) test allows scientists to infer the function of neurons just beneath the coil. In the piano players, the TMS mapped how much of the motor cortex controlled the finger movements needed for the piano exercise. What the scientists found was that after a week of practice, the stretch of motor cortex devoted to these finger movements took over surrounding areas like dandelions on a suburban lawn.

The finding was in line with a growing number of discoveries at the time showing that greater use of a particular muscle causes the brain to devote more cortical real estate to it. But Pascual-Leone did not stop there. He extended the experiment by having another group of volunteers merely think about practicing the piano exercise. They played the simple piece of music in their head, holding their hands still while imagining how they would move their fingers. Then they too sat beneath the TMS coil.

When the scientists compared the TMS data on the two groups--those who actually tickled the ivories and those who only imagined doing so--they glimpsed a revolutionary idea about the brain: the ability of mere thought to alter the physical structure and function of our gray matter. For what the TMS revealed was that the region of motor cortex that controls the piano-playing fingers also expanded in the brains of volunteers who imagined playing the music--just as it had in those who actually played it.

"Mental practice resulted in a similar reorganization" of the brain, Pascual-Leone later wrote. If his results hold for other forms of movement (and there is no reason to think they don't), then mentally practicing a golf swing or a forward pass or a swimming turn could lead to mastery with less physical practice. Even more profound, the discovery showed that mental training had the power to change the physical structure of the brain.

OVERTHROWING THE DOGMA

FOR DECADES, THE PREVAILING DOGMA IN neuroscience was that the adult human brain is essentially immutable, hardwired, fixed in form and function, so that by the time we reach adulthood we are pretty much stuck with what we have. Yes, it can create (and lose) synapses, the connections between neurons that encode memories and learning. And it can suffer injury and degeneration. But this view held that if genes and development dictate that one cluster of neurons will process signals from the eye and another cluster will move the fingers of the right hand, then they'll do that and nothing else until the day you die. There was good reason for lavishly illustrated brain books to show the function, size and location of the brain's structures in permanent ink.

The doctrine of the unchanging human brain has had profound ramifications. For one thing, it lowered expectations about the value of rehabilitation for adults who had suffered brain damage from a stroke or about the possibility of fixing the pathological wiring that underlies psychiatric diseases. And it implied that other brain-based fixities, such as the happiness set point that, according to a growing body of research, a person returns to after the deepest tragedy or the greatest joy, are nearly unalterable.

But research in the past few years has overthrown the dogma. In its place has come the realization that the adult brain retains impressive powers of "neuroplasticity"--the ability to change its structure and function in response to experience. These aren't minor tweaks either. Something as basic as the function of the visual or auditory cortex can change as a result of a person's experience of becoming deaf or blind at a young age. Even when the brain suffers a trauma late in life, it can rezone itself like a city in a frenzy of urban renewal. If a stroke knocks out, say, the neighborhood of motor cortex that moves the right arm, a new technique called constraint-induced movement therapy can coax next-door regions to take over the function of the damaged area. The brain can be rewired.

The first discoveries of neuroplasticity came from studies of how changes in the messages the brain receives through the senses can alter its structure and function. When no transmissions arrive from the eyes in someone who has been blind from a young age, for instance, the visual cortex can learn to hear or feel or even support verbal memory. When signals from the skin or muscles bombard the motor cortex or the somatosensory cortex (which processes touch), the brain expands the area that is wired to move, say, the fingers. In this sense, the very structure of our brain--the relative size of different regions, the strength of connections between them, even their functions--reflects the lives we have led. Like sand on a beach, the brain bears the footprints of the decisions we have made, the skills we have learned, the actions we have taken.

Read more . . .



Tuesday, March 20, 2007

The Science of Lasting Happiness

Through controlled experiments, Sonja Lyubomirsky explores ways to beat the genetic set point for happiness. Staying in high spirits, she finds, is hard work
Science Image:
The day I meet Sonja Lyubomirsky, she keeps getting calls from her Toyota Prius dealer. When she finally picks up, she is excited by the news: she can buy the car she wants in two days. Lyubomirsky wonders if her enthusiasm might come across as materialism, but I understand that she is buying an experience as much as a possession. The hybrid will be gentler on the environment, and a California state law letting some hybrids use the carpool lane promises a faster commute between her coastal Santa Monica home and her job at the University of California, Riverside, some 70 miles inland. Two weeks later, in late January, the 40-year-old Lyubomirsky, who smiles often and seems to approach life with zest and good humor, reports that she is "totally loving the Prius." But will the feeling wear off soon after the new-car smell, or will it last, making a naturally happy person even more so?


Read more . . .