Posts tagged children

Children with profound deafness who receive a cochlear implant had as much as five times the risk of having delays in areas of working memory, controlled attention, planning and conceptual learning as children with normal hearing, according to Indiana University research published May 22 in the Journal of the American Medical Association Otolaryngology—Head and Neck Surgery.

The authors evaluated 73 children implanted before age 7 and 78 children with normal hearing to determine the risk of deficits in executive functioning behaviors in everyday life.

Executive functioning, a set of mental processes involved in regulating and directing thinking and behavior, is important for focusing and attaining goals in daily life. All children in the study had average to above-average IQ scores. The results, reported in “Neurocognitive Risk in Children With Cochlear Implants,” are the first from a large-scale study to compare real-world executive functioning behavior in children with cochlear implants and those with normal hearing.

A cochlear implant device consists of an external component that processes sound into electrical signals that are sent to an internal receiver and electrodes that stimulate the auditory nerve. Although the device restores the ability to perceive many sounds to children who are born deaf, some details and nuances of hearing are lost in the process.

First author William Kronenberger, Ph.D., professor of clinical psychology in psychiatry at the IU School of Medicine and a specialist in neurocognitive and executive function testing, said that delays in executive functioning have been commonly reported by parents and others who work with children with cochlear implants. Based on these observations, his group sought to evaluate whether elevated risks of delays in executive functioning in children with cochlear implants exist, and what components of executive functioning were affected.

"In this study, about one-third to one-half of children with cochlear implants were found to be at-risk for delays in areas of parent-rated executive functioning such as concept formation, memory, controlled attention and planning. This rate was 2 to 5 times greater than that seen in normal-hearing children," reported Dr. Kronenberger, who also is co-chief of the ADHD-Disruptive Behavior Disorders Clinic and directs the psychology testing clinic at Riley Hospital for Children at IU Health.

"This is really innovative work," said co-author David B. Pisoni, Ph.D., director of the Speech Research Laboratory in the IU Department of Psychological and Brain Sciences. "Almost no one has looked at these issues in these children. Most audiologists, neuro-otologists, surgeons and speech-language pathologists — the people who work in this field — focus on the hearing deficit as a medical condition and have been less focused on the important discoveries in developmental science and cognitive neuroscience." Dr. Pisoni also is a Chancellors’ Professor of Psychological and Brain Sciences at IU Bloomington.

Richard Miyamoto, M.D., chair of the IU School of Medicine Department of Otolaryngology-Head and Neck Surgery and a pioneer in the field of cochlear implantation in children and adults, said this finding augments other research on interventions to help children with cochlear implants perform at a level similar to children without hearing deficits.

"The ultimate goal of our department’s research with cochlear implants has always been to influence higher-level neurocognitive functioning," Dr. Miyamoto said. "Much of the success we have seen to date clearly relates to the brain’s ability to process an incomplete signal. The current research will further assist in identifying gaps in our knowledge."

One possible answer may lie in earlier implantation, Dr. Miyamoto said. The age at which children are implanted has been steadily decreasing, which has produced significant improvement in spoken language outcomes. Research shows the early implantation is related to better outcomes in speech and understanding, and it is reasonable to believe that there may be less of a deficit in executive functioning with earlier implantation, said Dr. Miyamoto, who is the Arilla Spence DeVault Professor of Otolaryngology-Head and Neck Surgery and medical director of audiology and speech language pathology at the IU School of Medicine.

Preschoolers in the IU study were implanted at an average age of 18 months, and they had fewer executive function delays than school-age children who were implanted 10 months later, at an average age of 28 months. 

Children in the study were divided into two age groups: preschool (3 to 5 years) and school-age (7 to17 years). Using an established rating scale, parents rated executive function in everyday life for children with cochlear implants and for the control group with normal hearing.

"We compared parent ratings and looked at the percentage of children in each group who scored above a cut-off value that indicates at least a mild delay in executive functioning," Dr. Kronenberger said. "In the critical areas of controlled attention, working memory, planning and solving new problems, about 30 to 45 percent of the children with cochlear implants scored above the cut-off value, compared to about 15 percent or less of the children in the normal-hearing sample."

Dr. Kronenberger said the research also shows that many children develop average or better executive functioning skills after cochlear implantation.

"These results show that half or more of our group with cochlear implants did not have significant delays in executive functioning," Dr. Kronenberger said. "Cochlear implants produce remarkable gains in spoken language and other neurocognitive skills, but there is a certain amount of learning and catch-up that needs to take place with children who have experienced a hearing loss prior to cochlear implantation. So far, most of the interventions to help with this learning have focused on speech and language. Our findings show a need to identify and help some children in certain domains of executive functioning as well."

"We are now looking for early markers in children who are at risk before they get implants," Dr. Pisoni said. "It will be beneficial to identify as early as possible which children might be at risk for poor outcomes, and we need to understand the variability in the outcome and what can be done about it."

(Source: news.medicine.iu.edu)

TAU researcher finds that adults still think about numbers like kids

Children understand numbers differently than adults. For kids, one and two seem much further apart then 101 and 102, because two is twice as big as one, and 102 is just a little bigger than 101. It’s only after years of schooling that we’re persuaded to see the numbers in both sets as only one integer apart on a number line.

Now Dror Dotan, a doctoral student at Tel Aviv University’s School of Education and Sagol School of Neuroscience and Prof. Stanislas Dehaene of the Collège de France, a leader in the field of numerical cognition, have found new evidence that educated adults retain traces of their childhood, or innate, number sense — and that it’s more powerful than many scientists think.

"We were surprised when we saw that people never completely stop thinking about numbers as they did when they were children," said Dotan. "The innate human number sense has an impact, even on thinking about double-digit numbers." The findings, a significant step forward in understanding how people process numbers, could contribute to the development of methods to more effectively educate or treat children with learning disabilities and people with brain injuries.

Digital proof of a primal sense

Educated adults understand numbers “linearly,” based on the familiar number line from 0 to infinity. But children and uneducated adults, like tribespeople in the Amazon, understand numbers “logarithmically” — in terms of what percentage one number is of another. To analyze how educated adults process numbers in real time, Dotan and Dehaene asked the participants in their study to place numbers on a number line displayed on an iPad using a finger.

Previous studies showed that people who understand numbers linearly perform the task differently than people who understand numbers logarithmically. For example, linear thinkers place the number 20 in the middle of a number line marked from 0 to 40. But logarithmic thinkers like children may place the number 6 in the middle of the number line, because 1 is about the same percentage of 6 as 6 is of 40.

On the iPad used in the study, the participants were shown a number line marked only with “0” on one end and “40” on the other. Numbers popped up one at a time at the top of the iPad screen, and the participants dragged a finger from the middle of the screen down to the place on the number line where they thought each number belonged. Software tracked the path the finger took.

Changing course

Statistical analysis of the results showed that the participants placed the numbers on the number line in a linear way, as expected. But surprisingly — for only a few hundred milliseconds — they appeared to be influenced by their innate number sense. In the case of 20, for example, the participants drifted slightly rightward with their finger — toward where 20 would belong in a ratio-based number line — and then quickly corrected course. The results provide some of the most direct evidence to date that the innate number sense remains active, even if largely dormant, in educated adults.

"It really looks like the two systems in the brain compete with each other," said Dotan.

Significantly, the drift effect was found with two-digit as well as one-digit numbers. Many researchers believe that people can only convert two-digit numbers into quantities using the learned linear numerical system, which processes the quantity of each digit separately — for example, 34 is processed as 3 tens plus 4 ones. But Dotan and Dehaene’s research showed that the innate number sense is, in fact, capable of handling the complexity of two-digit numbers as well.

(Source: aftau.org)

Reaching for Froot Loops and grabbing Lego pieces to build a tower are different challenges for toddlers. Depending on what they’re trying to do, tots tend to develop handedness for different tasks at different ages, according to new research.

Most people are right-handed. Babies start using their right hand to reach for cereal nuggets by age 1. However, children take until age 4 to show such a preference when building Lego models. The findings, published in this month’s issue of Developmental Psychobiology, imply tendencies to use one hand more than the other emerge depending on the tasks kids confront, rather than their age.

Preference for the right or left hand is, in part, genetic. Prior studies have shown that some of these one-sided tendencies emerge early. Fetuses suck their right thumb more often than their left; newborns on their back turn to the right more frequently. Most children grow up to be right-handed—in part because of these innate, early leanings, scientists believe.

But the timing of when one hand emerges as the dominant one for most tasks remained unclear.

"As a parent and a scientist, I was surprised to find researchers thought 3-year-olds don’t display a hand preference," said neurobiologist Claudia Gonzalez of the University of Lethbridge in Alberta, Canada.

To study how handedness emerged between ages 1 to 5, Gonzalez and her colleagues assigned about 50 tiny participants to a familiar task: grabbing a colorful object or a tasty tidbit. Children ages 1 to 2 picked up Froot Loops or Cheerios to munch at snack time. Four- and 5-year-olds grasped Lego blocks to build a small model. Three-year-old subjects tackled both tasks.

Even the youngest children had strong right-handed leanings when reaching for food, the team found. Three-year-olds were right-handed eaters, but they were just as likely to use their left hand when playing with blocks. The 4- and 5-year-olds used their left hand to hold the base of their model steady, but they manipulated blocks into the correct positions with their other hand—a clear preference for right-handedness.

"There is a developmental milestone between the ages of 3 and 4 when something clicks," Gonzalez said. "Maybe they become more skilled, or they understand the task better."

Until that developmental “click,” this study shows hand preference isn’t constant across tasks – regardless of a child’s age.

The study “uses a very clever design to get at the question of how handedness varies across tasks,” said Klaus Libertus, an infant development researcher at the University of Pittsburgh. “We did not know handedness is connected to tasks in this way. I would have expected the 3-year-olds to show the same pattern on both tasks, especially since the demands were so similar.”

Developing a hand preference might also correlate with other functions that rely strongly on just one side of the brain, such as language and certain decision-making skills, Gonzalez noted. Preliminary data from children in her lab suggests that when handedness is evident earlier, these other functions also mature more quickly.

Finding the right task to study handedness at different ages will give researchers a firmer grasp on how young brains develop right - or left -handed tendencies, she said.

"You could say hand preference develops before 1, or you could say it doesn’t emerge until age 4—just depending on what task you are looking at," said Gonzalez.

(Source: livescience.com)

In 1979 China instituted the one-child policy, which limited every family to just one offspring in a controversial attempt to reduce the country’s burgeoning population. The strictly enforced law had the desired effects: in 2011 researchers estimated that the policy prevented 400 million births. In a new study in Science, researchers find that it has also caused China’s so-called little emperors to be more pessimistic, neurotic and selfish than their peers who have siblings.

Psychologist Xin Meng of the Australian National University in Canberra and her colleagues recruited 421 Chinese young adults born between 1975 and 1983 from around Beijing for a series of surveys and tests that evaluated a variety of psychological traits, such as trustworthiness and optimism. Almost all the participants born after 1979 were only children compared with about one fifth of those born before 1979. The study participants born after the policy went into effect were found to be both less trusting and less trustworthy, less inclined to take risks, less conscientious and optimistic, and less competitive than those born a few years earlier.

“Because of the one-child policy, parents are less likely to teach their child to be imaginative, trusting and unselfish,” Meng says. Without siblings, she notes, the need to share may not be emphasized, which could help explain these findings.

Only children in other parts of the world, however, do not show such striking differences from their peers. Toni Falbo, a social psychologist at the University of Texas at Austin, who was not involved in the study, suggests that larger social forces in China also probably contributed to these results. “There’s a lot of pressure being placed on [Chinese] parents to make their kid the best possible because they only had one,” Falbo says. These types of pressures could harm anyone, even if they had siblings, she says.

Whatever its cause, the personality profile of China’s little emperors may be troubling to a nation hoping to continue its ascent in economic prosperity. The traits marred by the one-child policy, the study authors point out, are exactly those needed in leaders and entrepreneurs.

(Source: scientificamerican.com)

When children with conduct problems see images of others in pain, key parts of their brains don’t react in the way they do in most people. This pattern of reduced brain activity upon witnessing pain may serve as a neurobiological risk factor for later adult psychopathy, say researchers who report their findings in the Cell Press journal Current Biology on May 2.

(Image: Shutterstock)

That’s not to say that all children with conduct problems are the same, or that all children showing this brain pattern in young life will become psychopaths. The researchers emphasize that many children with conduct problems do not persist with their antisocial behavior.

"Our findings indicate that children with conduct problems have an atypical brain response to seeing other people in pain," says Essi Viding of University College London. "It is important to view these findings as an indicator of early vulnerability, rather than biological destiny. We know that children can be very responsive to interventions, and the challenge is to make those interventions even better, so that we can really help the children, their families, and their wider social environment."

Conduct problems represent a major societal problem and include physical aggression, cruelty to others, and a lack of empathy, or “callousness.” In the United Kingdom, where the study was conducted, about five percent of children qualify for a diagnosis of conduct problems. But very little is known about the underlying biology.

In the new study, Viding, Patricia Lockwood, and their colleagues scanned children’s brains by functional magnetic resonance imaging (fMRI) to see how those with conduct problems differ in their response to viewing images of others in pain.

The brain images showed that, relative to controls, children with conduct problems show reduced responses to others’ pain specifically in regions of the brain known to play a role in empathy. The researchers also saw variation among those with conduct problems, with those deemed to be more callous showing lower brain activation than less callous individuals.

"Our findings very clearly point to the fact that not all children with conduct problems share the same vulnerabilities; some may have neurobiological vulnerability to psychopathy, while others do not," Viding says. "This raises the possibility of tailoring existing interventions to suit the specific profile of atypical processing that characterizes a child with conduct problems."

(Source: eurekalert.org)

Why do some children learn math more easily than others? Research from the Stanford University School of Medicine has yielded an unexpected new answer.

In a study of third-graders’ responses to math tutoring, Stanford scientists found that the size and wiring of specific brain structures predicted how much an individual child would benefit from math tutoring. However, traditional intelligence measures, such as children’s IQs and their scores on tests of mathematical ability, did not predict improvements from tutoring.

The research is the first to use brain scans to look for a link between math-learning abilities and brain structure or function, and also the first to compare neural and cognitive predictors of kids’ responses to tutoring. In addition, it provides information on the differences between how children and adults learn math, and could help researchers understand the origins of math-learning disabilities.

The study was published online April 29 in Proceedings of the National Academy of Sciences.

"What was really surprising was that intrinsic brain measures can predict change - we can actually predict how much a child is going to learn during eight weeks of math tutoring based on measures of brain structure and connectivity," said Vinod Menon, PhD, the study’s senior author and a professor of psychiatry and behavioral sciences. Menon is also a member of the Child Health Research Institute at Lucile Packard Children’s Hospital.

"The results are a significant step toward the development of targeted learning programs based on a child’s current as well as predicted learning trajectory," said the study’s lead author, Kaustubh Supekar, PhD, postdoctoral scholar in psychiatry and behavioral sciences.

Menon’s team focused on third-grade students ages 8 and 9 because these children are at a critical stage for acquiring basic arithmetic skills. The study included 24 third-graders who participated in a well-validated program of 15 to 20 hours of individualized math tutoring over eight weeks. The tutors explained new concepts to children and also got them to practice math skills with an emphasis on speed, and the sessions were tailored to each child’s level of understanding.

Before tutoring began, the children were given several standard neuropsychological assessments, including tests of IQ, working memory, reading and math-problem-solving abilities. Both before and after the eight-week tutoring period, children’s arithmetic performance was tested, and all children had structural and functional magnetic resonance imaging scans performed on their brains. To control for the effects of math instruction the children received at school (rather than during tutoring), a comparison group of 16 third-grade children who did not receive tutoring, but who had the same testing and brain scans before and after an eight-week interval, was also included in the study.

All 24 children receiving tutoring improved their arithmetic performance. Their performance efficiency, a composite measure of accuracy and speed of problem solving, improved an average of 67 percent after tutoring. But individual gains varied widely, ranging from 8 percent to 198 percent improvement. The children who did not receive tutoring did not show any change in arithmetic performance during the study.

When the researchers analyzed the children’s structural brain scans, they found that larger gray matter volume in three brain structures predicted greater ability to benefit from math tutoring. (The predictions were generated with a machine learning algorithm, the same type of data-analysis tool used to create movie recommendations for users of websites like Netflix, for example.) Of the three structures, the best predictor of improvement with tutoring was a larger hippocampus, a structure traditionally considered one of the brain’s most important memory centers. Functional connections between the hippocampus and several other brain regions, especially the prefrontal cortex and basal ganglia, also predicted ability to benefit from tutoring. These regions are important for forming long-term memories.

"The part of the brain that is recruited in memories for places and events also plays a pivotal role in determining how much and how well a child learns math," Supekar said.

None of the neuropsychological assessment scores, such as IQ or tests of working memory, could predict how much an individual child would benefit from tutoring.

The brain systems highlighted by this study - including the hippocampus, basal ganglia and prefrontal cortex - are different from those previously implicated for math learning in adults, the researchers noted. When solving math problems, adults rely on brain regions that are specialized for representing complex visual objects and processing spatial information.

And the findings suggest that the tutoring approach used, which was tailored to each child’s level of understanding and included lots of repetitive, high-speed arithmetic practice to help cement facts in children’s heads, works because it is compatible with the way their brains encode facts. “Memory resources provided by the hippocampal system create a scaffold for learning math in the developing brain,” Menon said. “Our findings suggest that, while conceptual knowledge about numbers is necessary for math learning, repeated, speeded practice and testing of simple number combinations is also needed to encode facts and encourage children’s reliance on retrieval - the most efficient strategy for answering simple arithmetic problems.” Once kids are able to pull up answers to basic arithmetic problems automatically from memory, their brains can tackle more complex problems.

The researchers’ next steps will include comparing brain structure and wiring in children with and without math learning disabilities, analyzing how the wiring of the brain changes in response to tutoring and examining whether lower-performing children’s brains can be exercised to help them learn math. “We’re pushing a very ecologically relevant model of learning,” Menon said. “Academic instruction should rely on validated instructional principles while incorporating individualized training to provide feedback on whether students are right or wrong, how they’re wrong and how they can improve their math skills.”

(Source: med.stanford.edu)