Posts tagged child development

Posts tagged child development
In a study of nearly 1,000 mother-child pairs, researchers from the Bloomberg School of Public health found that prenatal exposure to selective serotonin reuptake inhibitors (SSRIs), a frequently prescribed treatment for depression, anxiety and other disorders, was associated with autism spectrum disorder (ASD) and developmental delays (DD) in boys. The study, published in the online edition of Pediatrics, analyzed data from large samples of ASD and DD cases, and population-based controls, where a uniform protocol was implemented to confirm ASD and DD diagnoses by trained clinicians using validated standardized instruments.
The study included 966 mother-child pairs from the Childhood Autism Risks from Genetics and the Environment (CHARGE) Study, a population-based case-control study based at the University of California at Davis’ MIND Institute. The researchers broke the data into three groups: Those diagnosed with autism spectrum disorder (ASD), those with developmental delays (DD) and those with typical development (TD). The children ranged in ages two to five. A majority of the children were boys – 82.5% in the ASD group were boys, 65.6% in the DD group were boys and 85.6% in the TD were boys. While the study included girls, the substantially stronger effect in boys alone suggests possible gender difference in the effect of prenatal SSRI exposure.
“We found prenatal SSRI exposure was nearly 3 times as likely in boys with ASD relative to typical development, with the greatest risk when exposure took place during the first trimester,” said Li-Ching Lee, Ph.D., Sc.M., psychiatric epidemiologist in the Bloomberg School’s Department of Epidemiology. “SSRI was also elevated among boys with DD, with the strongest exposure effect in the third trimester.”
The data analysis was completed by Rebecca Harrington, Ph.D., M.P.H, in conjunction with her doctoral dissertation at the Bloomberg School. Dr. Lee was one of her advisors.
Serotonin is critical to early brain development; exposure during pregnancy to anything that influences serotonin levels can have potential effect on birth and developmental outcomes. The prevalence of ADS continues to rise. According to the Centers for Disease Control and Prevention, an estimated 1 in 68 children in the U.S. is identified with ADS, and it is almost five times more common among boys than girls. One may question whether the increased use of SSRI in recent years is a contributor to the dramatic rise of ASD prevalence.
"This study provides further evidence that in some children, prenatal exposure to SSRIs may influence their risk for developing an autism spectrum disorder,” said Irva Hertz-Picciotto, Ph.D., M.P.H., chief of the Division of Environmental and Occupational Health in the UC Davis Department of Public Health Sciences and a researcher at the UC Davis MIND Institute. “This research also highlights the challenge for women and their physicians to balance the risks versus the benefits of taking these medications, given that a mother’s underlying mental-health conditions also may pose a risk, both to herself and her child.”
Regarding treatment, the authors note that maternal depression itself carries risks for the fetus, and the benefits of using SSRI during pregnancy should be considered carefully against the potential harm. The researchers also note that large sample studies are needed to investigate the effects in girls with ASD. Limitations of the study acknowledged include the difficulty in isolating SSRI effects from those of their indications for use, lack of information on SSRI dosage precluded dose-response analyses, and the relatively small sample of DD children resulted in imprecise estimates of association, which should be viewed with caution.
(Source: jhsph.edu)

Study provides new insight into how toddlers learn verbs
Parents can help toddlers’ language skills by showing them a variety of examples of different actions, according to new research from the University of Liverpool.
Previous research has shown that verbs pose particular difficulties to toddlers as they refer to actions rather than objects, and actions are often different each time a child sees them.
To find out more about this area of child language, University psychologists asked a group of toddlers to watch one of two short videos.
They then examined whether watching a cartoon star repeat the same action, compared to a character performing three different actions, affected the children’s understanding of verbs.
Developmental psychologist, Dr Katherine Twomey, said: “Knowledge of how children start to learn language is important to our understanding of how they progress throughout preschool and school years.
“This is the first study to indicate that showing toddlers similar but, importantly, not identical actions actually helped them understand what a verb refers to, instead of confusing them as you might expect.”
Dr Jessica Horst from the University of Sussex who collaborated on the research added: “It is a crucial first step in understanding how what children see affects how they learn verbs and action categories, and provides the groundwork for future studies to examine in more detail exactly what kinds of variability affect how children learn words.”
How brain structures grow as memory develops
Our ability to store memories improves during childhood, associated with structural changes in the hippocampus and its connections with prefrontal and parietal cortices. New research from UC Davis is exploring how these brain regions develop at this crucial time. Eventually, that could give insights into disorders that typically emerge in the transition into and during adolescence and affect memory, such as schizophrenia and depression.
Located deep in the middle of the brain, the hippocampus plays a key role in forming memories. It looks something like two curving fingers branching forward from a common root. Each branch is a folded-over structure, with distinct areas in the upper and lower fold.
“For a long time it was assumed that the hippocampus didn’t develop at all after the first couple of years of life,” said Joshua Lee, a graduate student at the UC Davis Department of Psychology and Center for Mind and Brain. Improvements in memory were thought to be due entirely to changes in the brain’s outer layers, or cortex, that manage attention and strategies. But that picture has begun to change in the past five years.
Recently, Lee, Professor Simona Ghetti at the Center for Mind and Brain and Arne Ekstrom, assistant professor in the UC Davis Center for Neuroscience, used magnetic resonance imaging to map the hippocampus in 39 children aged eight to 14 years.
While subfields of the hippocampus have been mapped in adult humans and animal studies, it’s the first time that they have been measured in children, Ghetti said.
“This is really important to us, because it allows us to understand the heterogeneity along the hippocampus, which has been examined in human adults and other species” Ghetti said.
Looking at three subregions — the cornu ammonis (CA) 1, CA3/dentate gyrus and subiculum — they found that the first two expanded with age, with the most pronounced growth in the right hippocampus. Only in the oldest 25 percent of the children, within a few months either side of 14, did the sizes of all three regions decrease.
When they tested the children for memory performance, children with a larger CA3/dentate gyrus tended to perform better, they found. The work was published online March 15 by the journal Neuroimage.
In a related study in collaboration with the laboratory of Professor Silvia Bunge at UC Berkeley, published March 27 in Cerebral Cortex, the researchers also demonstrated how white matter connections projecting from the hippocampus to the brain cortex are related to memory function in children.
“White matter” tracts connect the prefrontal and parietal regions of the brain cortex, which control how we pay attention to things and engage in memory strategies, with the media-temporal lobe, the area that includes the hippocampus.
In the study, children performed a memory test that prompted them either to actively memorize an item — and therefore engage the prefrontal and parietal cortices — or to view an image passively. The ability to successfully modulate attention was linked to development of white matter tracts linking the prefrontal and parietal cortex tothe mediatemporal lobe, Ghetti said, but not to fronto-parietal connections.

Long-term study supports detrimental effects of television viewing on sleep in young children
A study following more than 1,800 children from ages 6 months to nearly 8 years found a small but consistent association between increased television viewing and shorter sleep duration. The presence of a television in the room where a child sleeps also was associated with less sleep, particularly in minority children. Investigators from MassGeneral Hospital for Children (MGHfC) and Harvard School of Public Health (HSPH) report their results – the first to examine the connection between television and sleep duration over several years – in the May issue of Pediatrics.
The study participants, children and their mothers, were enrolled in Project Viva, a long-term investigation of the health effects of several factors during pregnancy and after birth. This study analyzed information – reported by mothers when the children were around 6 months old and then annually for the next seven years – regarding how much time each day infants were in a room where a television was on, how much time older children watched television daily, whether children ages 4 to 7 slept in a room where a TV was present and their child’s average daily amount of sleep.
The study revealed that, over the course of the study, each additional hour of television viewing was associated with 7 fewer minutes of sleep daily, with the effects appearing to be stronger in boys than in girls. Racial and ethnic minority children were much more likely to sleep in a room where a television was present, and among those children, the presence of a bedroom television reduced average sleep around a half-hour per day.
The study authors note their results support previous short-term studies finding that both television viewing and sleeping in a room with a television decrease total sleep time, which can have negative effects on both mental and physical health.
Study Examines the Development of Children’s Prelife Reasoning
Most people, regardless of race, religion or culture, believe they are immortal. That is, people believe that part of themselves–some indelible core, soul or essence–will transcend the body’s death and live forever. But what is this essence? Why do we believe it survives? And why is this belief so unshakable?
A new Boston University study led by postdoctoral fellow Natalie Emmons and published in the January 16, 2014 online edition of Child Development sheds light on these profound questions by examining children’s ideas about “prelife,” the time before conception. By interviewing 283 children from two distinct cultures in Ecuador, Emmons’s research suggests that our bias toward immortality is a part of human intuition that naturally emerges early in life. And the part of us that is eternal, we believe, is not our skills or ability to reason, but rather our hopes, desires and emotions. We are, in fact, what we feel.
Emmons’ study fits into a growing body of work examining the cognitive roots of religion. Although religion is a dominant force across cultures, science has made little headway in examining whether religious belief–such as the human tendency to believe in a creator–may actually be hard-wired into our brains.
“This work shows that it’s possible for science to study religious belief,” said Deborah Kelemen, an Associate Professor of Psychology at Boston University and co-author of the paper. “At the same time, it helps us understand some universal aspects of human cognition and the structure of the mind.”
Most studies on immortality or “eternalist” beliefs have focused on people’s views of the afterlife. Studies have found that both children and adults believe that bodily needs, such as hunger and thirst, end when people die, but mental capacities, such as thinking or feeling sad, continue in some form. But these afterlife studies leave one critical question unanswered: where do these beliefs come from? Researchers have long suspected that people develop ideas about the afterlife through cultural exposure, like television or movies, or through religious instruction. But perhaps, thought Emmons, these ideas of immortality actually emerge from our intuition. Just as children learn to talk without formal instruction, maybe they also intuit that part of their mind could exist apart from their body.
Emmons tackled this question by focusing on “prelife,” the period before conception, since few cultures have beliefs or views on the subject. “By focusing on prelife, we could see if culture causes these beliefs to appear, or if they appear spontaneously,” said Emmons.
“I think it’s a brilliant idea,” said Paul Bloom, a Professor of Psychology and Cognitive Science at Yale who was not involved with the study. “One persistent belief is that children learn these ideas through school or church. That’s what makes the prelife research so cool. It’s a very clever way to get at children’s beliefs on a topic where they aren’t given answers ahead of time.”
Emmons interviewed children from an indigenous Shuar village in the Amazon Basin of Ecuador. She chose the group because they have no cultural prelife beliefs, and she suspected that indigenous children, who have regular exposure to birth and death through hunting and farming, would have a more rational, biologically-based view of the time before they were conceived. For comparison, she also interviewed children from an urban area near Quito, Ecuador. Most of the urban children were Roman Catholic, a religion that teaches that life begins only at conception. If cultural influences were paramount, reasoned Emmons, both urban and indigenous children should reject the idea of life before birth.
Emmons showed the children drawings of a baby, a young woman, and the same woman while pregnant, then asked a series of questions about the child’s abilities, thoughts and emotions during each period: as babies, in the womb, and before conception.
The results were surprising. Both groups gave remarkably similar answers, despite their radically different cultures. The children reasoned that their bodies didn’t exist before birth, and that they didn’t have the ability to think or remember. However, both groups also said that their emotions and desires existed before they were born. For example, while children generally reported that they didn’t have eyes and couldn’t see things before birth, they often reported being happy that they would soon meet their mother, or sad that they were apart from their family.
“They didn’t even realize they were contradicting themselves,” said Emmons. “Even kids who had biological knowledge about reproduction still seemed to think that they had existed in some sort of eternal form. And that form really seemed to be about emotions and desires.”
Why would humans have evolved this seemingly universal belief in the eternal existence of our emotions? Emmons said that this human trait might be a by-product of our highly developed social reasoning. “We’re really good at figuring out what people are thinking, what their emotions are, what their desires are,” she said. We tend to see people as the sum of their mental states, and desires and emotions may be particularly helpful when predicting their behavior. Because this ability is so useful and so powerful, it flows over into other parts of our thinking. We sometimes see connections where potentially none exist, we hope there’s a master plan for the universe, we see purpose when there is none, and we imagine that a soul survives without a body.
These ideas, while nonscientific, are natural and deep-seated. “I study these things for a living but even find myself defaulting to them. I know that my mind is a product of my brain but I still like to think of myself as something independent of my body,” said Emmons.
“We have the ability to reflect and reason scientifically, and we have the ability to reason based on our gut and intuition,” she added. “And depending on the situation, one may be more useful than the other.”
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)

Childhood bullying shown to increase likelihood of psychotic experiences in later life
New research has shown that being exposed to bullying during childhood will lead to an increased risk of psychotic experiences in adulthood, regardless of whether they are victims or perpetrators.
The study, published today in Psychological Medicine, assessed a cohort of UK children (ALSPAC) from birth to fully understand the extent of bullying on psychosis in later life – with some groups showing to be almost five times more likely to suffer from episodes at the age of 18.
The analysis, led by researchers from the University of Warwick, in association with colleagues at the University of Bristol, shows that victims, perpetrators and those who are both bullies and victims (bully-victims), are at an increased risk of developing psychotic experiences.
Even when controlling for external factors such as family factors or pre-existing behaviour problems, the study found that not only those children who were bullied over a number of years (chronic victims), but also the bullies themselves in primary school were up to four and a half times more likely to have suffered from psychotic experiences by the age of 18. Equally concerning is that those children who only experienced bullying for brief periods (e.g. at 8 or 10 years of age) were at increased risk for psychotic experiences.
The term ‘psychotic experiences’ covers a range of experiences, from hearing voices and seeing things that are not there to paranoia. These experiences, if persistent, are highly distressing and disruptive to everyday life. They are diagnosed by GPs or psychiatrists as “psychotic disorders” such as schizophrenia. Exact diagnosis is difficult and requires careful assessment as in this study.
Professor Dieter Wolke of the University of Warwick explained, “We want to eradicate the myth that bullying at a young age could be viewed as a harmless rite of passage that everyone goes through – it casts a long shadow over a person’s life and can have serious consequences for mental health”
“These numbers show exactly how much childhood bullying can impact on psychosis in adult life. It strengthens on the evidence base that reducing bullying in childhood could substantially reduce mental health problems. The benefit to society would be huge, but of course, the greatest benefit would be to the individual.”
When controlling for external factors such as family factors or pre-existing behaviour problems, the study found that not only those children who were bullied over a number of years (chronic victims), but also the bullies themselves in primary school were up to four and a half times more likely to have suffered from psychotic experiences by the age of 18. Equally concerning is that those children who only experienced bullying for brief periods (e.g. at 8 or 10 years of age) were at increased risk for psychotic experiences.
Wolke’s team have previously looked at the impact of bullying on psychotic symptoms in 12 year olds, and there have been a range of short term studies that confirm the relation between being a victim of bullying and psychotic symptoms. This study, however, is the first to report the long term impact of being involved in bullying during childhood - whether victim, bully or bully-victim – on psychotic experiences in late adolescence or adulthood.
Professor Wolke added, “The results show that interventions against bullying should start early, in primary school, to prevent long term serious effects on children’s mental health. This clearly isn’t something that can wait until secondary school to be resolved; the damage may already have been done.”
Messy children make better learners
Attention, parents: The messier your child gets while playing with food in the high chair, the more he or she is learning.
Researchers at the University of Iowa studied how 16-month-old children learn words for nonsolid objects, from oatmeal to glue. Previous research has shown that toddlers learn more readily about solid objects because they can easily identify them due to their unchanging size and shape. But oozy, gooey, runny stuff? Not so much.
New research shows that changes if you put toddlers in a setting they know well. In those instances, word learning increases, because children at that age are “used to seeing nonsolid things in this context, when they’re eating,” says Larissa Samuelson, associate professor in psychology at the UI who has worked for years on how children learn to associate words with objects. “And, if you expose them to these things when they’re in a highchair, they do better. They’re familiar with the setting and that helps them remember and use what they already know about nonsolids.”
In a paper published in the journal Developmental Science, Samuelson and her team at the UI tested their idea by exposing 16-month-olds to 14 nonsolid objects, mostly food and drinks such as applesauce, pudding, juice, and soup. They presented the items and gave them made-up words, such as “dax” or “kiv.” A minute later, they asked the children to identify the same food in different sizes or shapes. The task required the youngsters to go beyond relying simply on shape and size and to explore what the substances were made of to make the correct identification and word choice.
Not surprisingly, many children gleefully dove into this task by poking, prodding, touching, feeling, eating—and yes, throwing—the nonsolids in order to understand what they were and make the correct association with the hypothetical names. The toddlers who interacted the most with the foods—parents, interpret as you want—were more likely to correctly identify them by their texture and name them, the study determined. For example, imagine you were a 16-month-old gazing at a cup of milk and a cup of glue. How would you tell the difference by simply looking?
“It’s the material that makes many nonsolids,” Samuelson notes, “and how children name them.”
The setting matters, too, it seems. Children in a high chair were more apt to identify and name the food than those in other venues, such as seated at a table, the researchers found.
“It turns out that being in a high chair makes it more likely you’ll get messy, because kids know they can get messy there,” says Samuelson, the senior author on the paper.
The authors say the exercise shows how children’s behavior, environment (or setting), and exploration help them acquire an early vocabulary—learning that is linked to better later cognitive development and functioning.
“It may look like your child is playing in the high chair, throwing things on the ground, and they may be doing that, but they are getting information out of (those actions),” Samuelson contends. “And, it turns out, they can use that information later. That’s what the high chair did. Playing with these foods there actually helped these children in the lab, and they learned the names better.”
“It’s not about words you know, but words you’re going to learn,” Samuelson adds.
Innate ability to identify quantities previews future mathematics performance

Babies who are good at telling the difference between large and small groups of items even before learning how to count are more likely to do better with numbers in the future, according to new research from the Duke Institute for Brain Sciences.
The use of Arabic numerals to represent different values is a characteristic unique to humans, not seen outside our species. But we aren’t born with this skill. Infants don’t have the words to count to 10. So, scientists have hypothesized that the rudimentary sense of numbers in infants is the foundation for higher-level math understanding.
A new study, appearing online in the Oct. 21 Proceedings of the National Academy of Sciences, suggests that children do, in fact, tap into this innate numerical ability when learning symbolic mathematical systems. The Duke researchers found that the strength of an infant’s inborn number sense can be predictive of the child’s future mathematical abilities.
"When children are acquiring the symbolic system for representing numbers and learning about math in school, they’re tapping into this primitive number sense," said Elizabeth Brannon, Ph.D., a professor of psychology and neuroscience, who led the study. "It’s the conceptual building block upon which mathematical ability is built."
Brannon explained that babies come into the world with a rudimentary understanding referred to as a primitive number sense. When looking at two collections of objects, primitive number sense allows them to identify which set is numerically larger even without verbal counting or using Arabic numerals. For example, a person instinctively knows a group of 15 strawberries is more than six oranges, just by glancing.
Understanding how infants and young children conceptualize and understand number can lead to the development of new mathematics education strategies, said Brannon’s colleague, Duke psychology and neuroscience graduate student Ariel Starr. In particular, this knowledge can be used to design interventions for young children who have trouble learning mathematics symbols and basic methodologies.
To test for primitive number sense, Brannon and Starr analyzed 48 6-month-old infants to see whether they could recognize numerical changes, capitalizing on the interest most babies show in things that change. They placed each baby in front of two screens, one that always showed the same number of dots (e.g., eight), changing in size and position, and another that switched between two different numerical values (e.g., eight and 16 dots). All the arrays of dots changed frequently in size and position. In this task, babies that could tell the difference between the two numerical values (e.g., eight and 16) looked longer at the numerically changing screen.
Brannon and Starr then tested the same children at 3.5 years of age with a non-symbolic number comparison game. The children were shown two different arrays and asked to choose which one had more dots without counting them. In addition, the children took a standardized math test scaled for pre-schoolers, as well as a standardized IQ test. Finally, the researchers gave the children a simple verbal task to identify the largest number word each child could concretely understand.
"We found that infants with higher preference scores for looking at the numerically changing screen had better primitive number sense three years later compared to those infants with lower scores," Starr said. "Likewise, children with higher scores in infancy performed better on standardized math tests."
Brannon said the findings point to a real connection between symbolic math and quantitative abilities that are present in infancy before education takes hold and shapes our mathematical abilities.
"Our study shows that infant number sense is a predictor of symbolic math," Brannon said. "We believe that when children learn the meaning of number words and symbols, they’re likely mapping those meanings onto pre-verbal representations of number that they already have in infancy," she said.
"We can’t measure a baby’s number sense ability at 6 months and know how they’ll do on their SATs," Brannon added. "In fact our infant task only explains a small percentage of the variance in young children"s math performance. But our findings suggest that there is cognitive overlap between primitive number sense and symbolic math. These are fundamental building blocks."
(Source: today.duke.edu)

Children’s Computation of Complex Linguistic Forms: A Study of Frequency and Imageability Effects
This study investigates the storage vs. composition of inflected forms in typically-developing children. Children aged 8–12 were tested on the production of regular and irregular past-tense forms. Storage (vs. composition) was examined by probing for past-tense frequency effects and imageability effects – both of which are diagnostic tests for storage – while controlling for a number of confounding factors. We also examined sex as a factor. Irregular inflected forms, which must depend on stored representations, always showed evidence of storage (frequency and/or imageability effects), not only across all children, but also separately in both sexes. In contrast, for regular forms, which could be either stored or composed, only girls showed evidence of storage. This pattern is similar to that found in previously-acquired adult data from the same task, with the notable exception that development affects which factors influence the storage of regulars in females: imageability plays a larger role in girls, and frequency in women. Overall, the results suggest that irregular inflected forms are always stored (in children and adults, and in both sexes), whereas regulars can be either composed or stored, with their storage a function of various item- and subject-level factors.