August 21, 2014
How Do Kids Learn Math?
The Answer Is So Simple...
By LAURAN NEERGAARD
AP Medical Writer
Washington (AP) At some point, children quit counting your fingers and just know the answer. Now scientists have put youngsters into brain scanners to find out why, and watched how the brain reorganizes itself as kids learn math.
The take-home advice: drilling your kids on simple addition and multiplication may pay off.
``Experience really does matter,’’ said Dr. Kathy Mann Koepke of the National Institutes of Health, which funded the research.
Healthy children start making that switch between counting to what’s called fact retrieval when they’re 8 years old to 9 years old, when they’re still working on fundamental addition and subtraction. How well kids make that shift to memory-based problem-solving is known to predict their ultimate math achievement.
Those who fall behind ``are impairing or slowing down their math learning later on,’’ Mann Koepke said.
But why do some kids make the transition easier than others?
To start finding out, Stanford University researchers first peeked into the brains of 28 children as they solved a series of simple addition problems inside a brain-scanning MRI machine.
No scribbling out the answer: The 7- to 9-year-olds saw a calculation—three plus four equals seven, for example—flash on a screen and pushed a button to say if the answer was right or wrong. Scientists recorded how quickly they responded and what regions of their brain became active as they did.
In a separate session, they also tested the kids face to face, watching if they moved their lips or counted on their fingers, for comparison with the brain data.
The children were tested twice, roughly a year apart. As the kids got older, their answers relied more on memory and became faster and more accurate, and it showed in the brain. There was less activity in the prefrontal and parietal regions associated with counting and more in the brain’s memory center, the hippocampus, the researchers reported Sunday in Nature Neuroscience.
The hippocampus is sort of like a relay station where new memories come in—short-term working memory—and then can be sent elsewhere for longer-term storage and retrieval. Those hippocampal connections increased with the kids’ math performance.
``The stronger the connections, the greater each individual’s ability to retrieve facts from memory,’’ said Dr. Vinod Menon, a psychiatry professor at Stanford and the study’s senior author.
But that’s not the whole story.
Next, Menon’s team put 20 adolescents and 20 adults into the MRI machines and gave them the same simple addition problems. It turns out that adults don’t use their memory-crunching hippocampus in the same way. Instead of using a lot of effort, retrieving six plus four equals 10 from long-term storage was almost automatic, Menon said.
In other words, over time the brain became increasingly efficient at retrieving facts. Think of it like a bumpy, grassy field, NIH’s Mann Koepke explained. Walk over the same spot enough and a smooth, grass-free path forms, making it easier to get from start to end.
If your brain doesn’t have to work as hard on simple math, it has more working memory free to process the teacher’s brand-new lesson on more complex math.
``The study provides new evidence that this experience with math actually changes the hippocampal patterns, or the connections. They become more stable with skill development,’’ she said. ``So learning your addition and multiplication tables and having them in rote memory helps.’’
Quiz your child in different orders, she advised—nine times three and then 10 times nine—to make sure they really remember and didn’t have to think it through.
While the study focuses on math, Mann Koepke said cognitive development in general probably works the same way. After all, kids who match sounds to letters earlier learn to read faster.
Stanford’s Menon said the next step is to study what goes wrong with this system in children with math learning disabilities, so that scientists might try new strategies to help them learn.
Kai The Shelter Dog Is Now Top Dog At SA Fire Department
By MITCHELL FERMAN
San Antonio Express-News
San Antoniol (AP) On a recent afternoon, Kai—a former shelter dog whose outlook once looked bleak—hopped out of a black Ford Crown Victoria and was ordered to ``seek.’’ Once that word was spoken, the man on the other end of her nylon leash had to hold on tight. ``It’s like putting a leash on lightning,’’ said Fire Department arson investigator Justin Davis, Kai’s handler. The 6-year-old black Labrador retriever’s humble beginnings—caught by a dog catcher in Illinois, where she probably would have been euthanized had she not been rescued by the local Humane Society—now are nearly forgotten, several years and 1,000 miles away. These days, she’s known locally as the Fire Department’s lone arson dog, and her reputation is growing well beyond the boundaries of San Antonio.
She’s one of the nation’s top working canines, according to a recent online contest that will result in her and Davis traveling to California next month to compete against other service dogs. But the recent leash exercise—a typical training session in which Kai was tasked with finding petroleum-based flammable liquids at the SAFD Training Academy had little to do with a contest.
Kai yanked Davis inside a dark, charred training building and sniffed along each wall. She meticulously found each liquid drop that had been placed earlier by Davis, looking up at her partner and offering a bark as he reciprocated with a treat.
The dog has been sniffing out such liquids, in training and in more than 200 live situations, for the department since becoming Davis’ partner in July 2010.
She never has seemed to have an off day, say those who work with her— one of the reasons she’s a finalist for the American Humane Association’s Hero Dog Awards.
Kai already won the top arson dog category and will now compete against dogs that won the seven other categories: law enforcement, guide/hearing, search and rescue, military, service, emerging hero and therapy.
Kai & her ball
The grand prize winner will be announced at a California black-tie gala.
In the meantime, the duo has the usual full schedule planned, including appearances at hospitals, schools and forensics classes. One of the few times Davis remembers Kai acting up was during one such appearance, at Tejeda Middle School. Once in the classroom, Kai started inexplicably shaking and barking.
Then Davis realized the distraction: Each table in the room had tennis balls, Kai’s version of Kryptonite, attached to the bottom of each leg.
``She’s amazing, she’s perfect (but) there’s one thing she can’t control,’’ Davis told the San Antonio Express-News. ``If you brought out a tennis ball right now her eyes would turn different and glaze over. It’s like a drug.’’
Kai goes everywhere with Davis. They share an office, with the dog’s circular bed positioned under his desk. She sometimes steps out to play ball or tug-of-war with one of the other 13 arson investigators, but Davis estimates they’ve been separated no more than a couple of weeks over the past four years.
The mutual trust started after Davis earned a scholarship to get paired with an arson dog through a program that trains dogs in Maine. Kai had ended up there from the McLean County Humane Society in Illinois after she was recognized for her ability to follow directions. After more than 500 hours of initial training together and years of working side by side, Kai knows Davis won’t let anything happen to her and Davis knows Kai won’t leave his side, he said.
One time, during an arson investigation that Davis described as being in a rough part of town, Davis was reaching in his trunk when he saw Kai turn around.
``There were these three dogs charging at us from these guys a few houses down,’’ Davis said. ``Now, there’s no way of knowing if these dogs were sent to attack us or what. ``But Kai turned around and stood there next to me. I yelled out at the guys to call their dogs off—I never want to hurt an animal, but I would never let anything happen to Kai. And she stood there right next me the whole time.’’ Now that she has become such an integral part of the department, investigator Tim Bays said, he often marvels at how they once got along without her. ``She does in 10 seconds what can take us hours,’’ Bays said. ``And she never has a frickin’ bad day.
``I’ll tell you, it’s good to see Justin and Kai roll up to a scene. It’s like seeing a cavalry.’’
This Week In The Civil War: Ft. Sumter Reduced To Rubble
This Week in The Civil War, for week of Sunday, Aug. 24: South Carolina fighting, violence in Kansas.
The Associated Press reported in a dispatch dated Aug. 25, 1863: ``The bombardment of (Fort) Sumter still continues, and the south wall has been demolished almost to its base.’’ For weeks now, Union forces have been attempting to smash through heavy Confederate defenses on islands ringing Charleston Harbor off South Carolina’s coast.
The AP dispatch added that rebel batteries have answered the Union’s artillery bombardment with bursts of return fire at short intervals. Federal forces reported that their casualties are few and that ``every confidence in success is felt by the officers and troops.’’
At one point the bombardment became so intense, AP reported, that the entire southwest side of Fort Sumter has been reduced to rubble—``nothing but a heap of ruins.’’ Even the Confederate flag flying above the fort was shot away during one barrage, the AP reported.
In Kansas, meanwhile, authorities report the discovery 151 years ago this week of 28 bodies—part of the sectarian violence that the war has touched off in the West. Witnesses said in dispatches that the discovery of murdered civilians in one town was ``heart-rending and sickening.’’