Friday, May 15, 2015

the science of craving

moreintelligentlife |  A hush falls over the 7,500-seat auditorium reserved for lectures by eminent neuroscientists, as Dr Kent Berridge, of the University of Michigan, is called on stage to present his pioneering research into pleasure and desire. If anyone can reveal why so many of us can’t say no to the grande or the milkshake, despite knowing the consequences, it is Berridge.

For almost three decades, he has swum against the tide of established thinking, to map the brain mechanics of the reward system—the part of the brain that lights up on scans when people enjoy something, whether it’s cake, snogging, heroin or Facebook. It has been a long and winding journey, featuring cameos from Iggy Pop and the Dalai Lama, and a supporting cast of hedonistic lab rats.

THE REWARD SYSTEM exists to ensure we seek out what we need. If having sex, eating nutritious food or being smiled at brings us pleasure, we will strive to obtain more of these stimuli and go on to procreate, grow bigger and find strength in numbers. Only it’s not as simple in the modern world, where people can also watch porn, camp out in the street for the latest iPhone or binge on KitKats, and become addicted, indebted or overweight. As Aristotle once wrote: “It is of the nature of desire not to be satisfied, and most men live only for the gratification of it.” Buddhists, meanwhile, have endeavoured for 2,500 years to overcome the suffering caused by our propensity for longing. Now, it seems, Berridge has found the neuro-anatomical basis for this facet of the human condition—that we are hardwired to be insatiable wanting machines.

If you had opened a textbook on brain rewards in the late 1980s, it would have told you that the dopamine and opioids that swished and flickered around the reward pathway were the blissful brain chemicals responsible for pleasure. The reward system was about pleasure and somehow learning what yields it, and little more. So when Berridge, a dedicated young scientist who was more David than Goliath, stumbled upon evidence in 1986 that dopamine did not produce pleasure, but in fact desire, he kept quiet. It wasn’t until the early 1990s, after rigorous research, that he felt bold enough to go public with his new thesis. The reward system, he then asserted, has two distinct elements: wanting and liking (or desire and pleasure). While dopamine makes us want, the liking part comes from opioids and also endocannabinoids (a version of marijuana produced in the brain), which paint a “gloss of pleasure”, as Berridge puts it, on good experiences. For years, his thesis was contested, and only now is it gaining mainstream acceptance. Meanwhile, Berridge has marched on, unearthing more and more detail about what makes us tick. His most telling discovery was that, whereas the dopamine/wanting system is vast and powerful, the pleasure circuit is anatomically tiny, has a far more fragile structure and is harder to trigger.

Tuesday, May 12, 2015

matchmaking is the killer-application for these microbiome fingerprints...,

TheScientist | People harbor distinctive sets of microbes, the genetic signatures of which can be used to identify individuals participating in the Human Microbiome Project, according to work published today (May 11) in PNAS

“Each of us personally has a specific set of bugs that are an extension of us, just the same way that our own genome is a part of what defines us,” said coauthor Curtis Huttenhower, a biostatistician at the Harvard School of Public Health.

The study suggests that microbiome sequencing may someday have utility in criminal investigations, for example, but it also raises questions about how microbiome sequence data should best be handled to protect the privacy of study participants.

Researchers previously showed that they could differentiate between small groups of individuals who had touched computer keyboards or mice by matching their skin microbiota to the microbes left on the computer equipment. A team led by Jack Gilbert, a microbiologist at Argonne National Laboratory in Illinois, recently showed that families leave their unique microbial signatures in the rooms of their houses. The new work is “interesting confirmation that we have unique microbial strain-level associations with our body,” said Gilbert, who was not involved in the research.

Huttenhower and his colleagues developed an algorithm to identify microbiome signatures based on both 16S ribosomal RNA sequences and whole metagenome shotgun sequencing. They assessed the abundance of microbial taxons and also of specific microbial genes and other stretches of DNA.

The researchers sought to identify the minimum set of microbiome features that would be necessary to uniquely identify a person, drawing from the field of data transmission. “The coding problem is actually very similar to what’s used to transmit information on the Internet or over a cellphone,” Huttenhower explained. “You want to represent [the information] using a code that’s short—so you don’t use up a bunch of bandwidth—but robust, so that small errors don’t change your message.”

Monday, May 4, 2015

kids prefer standing and moving to sitting? what a novel concept...

SAN RAFAEL (CBS SF) — A lot of people say we should stand up for education but, at Vallecito Elementary in San Rafael, they’re actually doing it.
“To me, this is the wave of the future,” says 4th grade teacher Maureen Zink.
In four of the school’s classrooms, chairs have been removed and students spend the day standing at their desks. Some parents, concerned about how sedentary kids have become, donated money for the new desks.
A lot of the kids thought the change was weird and it took a few weeks for legs to stop being sore.
But then something really weird started happening — the kids began to like it.
“You can get your bones stretched out and you don’t, like, want to get it stretched in together again,” 1st grader Marley Metzger explained.
To which 4th grader Lola Maggioncalta adds, “To me it’s really fun and it makes me more focused.”

just sit STILL!

The TUTTIE fidget
Science Direct | For decades, frustrated parents and teachers have barked at fidgety children with ADHD to "Sit still and concentrate!"
But new research conducted at UCF shows that if you want ADHD kids to learn, you have to let them squirm. The foot-tapping, leg-swinging and chair-scooting movements of children with attention-deficit/hyperactivity disorder are actually vital to how they remember information and work out complex cognitive tasks, according to a study published in an early online release of the Journal of Abnormal Child Psychology.
The findings show the longtime prevailing methods for helping children with ADHD may be misguided.
"The typical interventions target reducing hyperactivity. It's exactly the opposite of what we should be doing for a majority of children with ADHD," said one of the study's authors, Mark Rapport, head of the Children's Learning Clinic at the University of Central Florida. "The message isn't 'Let them run around the room,' but you need to be able to facilitate their movement so they can maintain the level of alertness necessary for cognitive activities."
The research has major implications for how parents and teachers should deal with ADHD kids, particularly with the increasing weight given to students' performance on standardized testing. The study suggests that a majority of students with ADHD could perform better on classroom work, tests and homework if they're sitting on activity balls or exercise bikes, for instance.
The study at the UCF clinic included 52 boys ages 8 to 12. Twenty-nine of the children had been diagnosed with ADHD and the other 23 had no clinical disorders and showed normal development.