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40 Percent of 3-month-old Infants Are Regularly Watching TV, DVDs Or Videos

September 29th, 2010

A large number of parents are ignoring warnings from the American Academy of Pediatrics and are allowing their very young children to watch television, DVDs or videos so that by 3 months of age 40 percent of infants are regular viewers. That number jumps to 90 percent of 2-year-olds, according to a new study by researchers at the University of Washington and Seattle Childrens Hospital Research Institute. The findings are being published today in the Archives of Pediatrics and Adolescent Medicine. The study is the first to look at the trajectory of media viewing in the first two years of life and to explore the content of what is being watched. The research also explores parents reasons for permitting it. Exposure to TV takes time away from more developmentally appropriate activities such as a parent or adult caregiver and an infant engaging in free play with dolls, blocks or cars, said Frederick Zimmerman, lead author of the study and a UW associate professor of health services. While appropriate television viewing at the right age can be helpful for both children and parents, excessive viewing before age 3 has been shown to be associated with problems of attention control, aggressive behavior and poor cognitive development. Early television viewing has exploded in recent years, and is one of the major public health issues facing American children.

Co-authors of the study are Dr. Dimitri Christakis, a pediatrics researcher at Seattle Childrens Hospital Research Institute and a UW associate professor of medicine, and Andrew Meltzoff, co-director of the UWs Institute for Learning and Brain Sciences. This study is important because it teaches us about the media diet of infants who are too young to speak for themselves. Most parents seek whats best for their child, and we discovered that many parents believe that they are providing educational and brain development opportunities by exposing their babies to 10 to 20 hours of viewing per week, said Meltzoff, a developmental psychologist who is the Job and Gertrud Tamaki endowed chair in psychology at the UW.

We need more research on both the positive and negative effects of a steady diet of baby TV and DVD viewing. But parents should feel confident that high-quality social interaction with babies, including reading and talking with them, provides all the stimulation that the growing brain needs. Its not as though TV or a DVD provides an extra vitamin of some kind in the first two years of life, where we concentrated our research in this study. This area is one in which science, health and public policy all meet. We need to get our facts right so we can productively advise parents who so desperately want to do the right thing. The researchers conducted random telephone surveys of more than 1,000 families in Minnesota and Washington with a child born in the previous two years, and found the median age at which infants were regularly exposed to media was 9 months. Among those who watched TV, DVDs or videos, the average daily viewing time jumped from one hour per day for those children younger than 12 months to more than 1 hours a day by 24 months.

The three most important and common reasons cited by parents for allowing their children to watch TV, DVDs or videos were:

29 percent believed these media were educational or were good for the childs brain.

23 percent said viewing was enjoyable or relaxing for the child.

21 percent used these media as an electronic babysitter so they could do other things.

Even though educational content was the top reason given by parents, only about half the infant viewing time was reported to be in what researchers classified as a childrens educational category. This included educational TV programs such as Sesame Street and Arthur and DVDs or videos such as Blues Clues. The remaining viewing time was roughly split among childrens non-educational programs, baby DVDs or videos and grown-up television. Although parents believe in the educational value of TV, DVDs and videos, just 32 percent of parents always watched with their children. Parents also had an inflated idea of how much of these media other children were watching and believed that their children viewed less than the average amount. The study indicated that the perceived average viewing for other families is 73 percent higher than the actual average. At the end of the day the amount of TV viewing is based on what parents think is normal, said Zimmerman. Perceptions of norms tend to shape behavior even if those norms are inflated. So what can parents do to reduce the amount of time their kids spend in front of the tube? Zimmerman has several suggestions. Parents often turn to TV for a break. A better suggestion would be to provide kids with simple activities to do. When parents are cooking, for example, they could have a low drawer with plastic dishes or wooden spoons available that a child can play with or make noise. This gives the child something to be engaged with while taking pressure off the parent.

“A parent can also enjoy reading a fun or familiar book to a child, he said. The child benefits from being close while the parent can get a breather. Children thrive on physical closeness.

Zimmerman and Christakis are the authors of the book The Elephant in the Living Room, Make Television Work for Your Kids and Meltzoff is co-author of The Scientist in the Crib: What Early Learning Tells Us about the Mind.

Dr. Perlmutter’s comment:

This supports the guidlines we provide in Raise a Smarter Child by Kindergarten

Study: TV can impair speech development of young children

June 3rd, 2009

From USAToday.com:

A study released Monday adds to the debate over whether television impairs children’s language development. The study finds that parents and children virtually stop talking to each other when the TV is on, even if they’re in the same room.
For every hour in front of the TV, parents spoke 770 fewer words to children, according to a study of 329 children, ages 2 months to 4 years, in the June issue of Archives of Pediatrics & Adolescent Medicine. Adults usually speak about 941 words an hour.

Children vocalized less, too, says author Dimitri Christakis of the Seattle Children’s Research Institute. In some cases, parents may have spoken less because they sat a child in front of a TV and left the room, he says. In others, parents simply zoned out themselves while watching TV with a child. Researchers didn’t note the content of the TV shows.

Parents may not realize how little they interact with children when a TV is on, Christakis says. A mother may think she’s engaged with a baby because they’re both on the floor playing blocks. But if a TV is on in the background, the two of them talk much less, he says.

That may help explain earlier studies finding that babies who watch a lot of TV know fewer words, although they catch up to their peers by 16 months, Christakis says. “Babies learn language from hearing it spoken,” he says.

Christakis and his colleagues fitted children with digital devices that recorded everything they heard or said one day a month for an average of six months. A speech-recognition program, which could differentiate TV content from human voices, compared the number of words exchanged when televisions were on or off.

Victor Strasburger, a professor of pediatrics at the University of New Mexico, describes the latest report as “an excellent, creative study.”

It’s the seventh study to suggest that TV hurts children’s language development, Strasburger says. A March report from Harvard Medical School found that watching TV neither helped nor harmed children’s language skills.

Though Christakis acknowledges that there is still some debate about whether watching television is harmful, he says there’s no evidence to show that it’s helpful. That’s why the American Academy of Pediatrics recommends no TV for babies under age 2.

“We need to avoid parking babies in front of screens,” Strasburger says. “Parents need to realize they need to be the primary entertainment for their babies. Parents are movie stars when their kids are babies. It doesn’t last long.”

Child abuse ‘alters stress gene’

February 23rd, 2009

From news.bbc.co.uk

Analysis of brain tissue from adults who had committed suicide found key genetic changes in those who had suffered abuse as a child.

It affects the production of a receptor known to be involved in stress responses, the researchers said.

The Nature Neuroscience study underpins the impact of stress on early brain development, experts said.

Previous research has shown that abuse in childhood is associated with an increased reaction to stressful circumstances.

“Whilst these results obviously need to be replicated, they provide a mechanism by which experiences early in life can have an effect on behaviour later in adulthood”
Dr Jonathan Mill

But exactly how environmental factors interact with genes and contribute to depression or other mental disorders in adulthood is not well understood.

A research team led by McGill University, in Montreal, examined the gene for the glucocorticoid receptor – which helps control the response to stress – in a specific brain region of 12 suicide victims with a history of child abuse and 12 suicide victims who did not suffer abuse when younger.

They found chemical changes which reduced the activity of the gene in those who suffered child abuse.

And they showed this reduced activity leads to fewer glucocorticoid receptors.

Those affected would have had an abnormally heightened response to stress, the researchers said.

Long-term

It suggests that experience in childhood when the brain is developing, can have a long-term impact on how someone responds to stressful situations.

But study leader Professor Michael Meaney said they believe these biochemical effects could also occur later in life.

“If you’re a public health individual or a child psychologist you could say this shows you nothing you didn’t already know.

“But until you show the biological process, many people in government and policy-makers are reluctant to believe it’s real.

“Beyond that, you could ask whether a drug could reverse these effects and that’s a possibility.”

Dr Jonathan Mill, from the Institute of Psychiatry at Kings College London said the research added to growing evidence that environmental factors can alter the expression of genes – a process known as epigenetics.

“Whilst these results obviously need to be replicated, they provide a mechanism by which experiences early in life can have an effect on behaviour later in adulthood.

“The exciting thing about epigenetic alterations is that they are potentially reversible, and thus perhaps a future target for therapeutic intervention.”

Brain Matures A Few Years Late In ADHD, But Follows Normal Pattern

November 16th, 2007

From ScienceDaily.com

In youth with attention deficit hyperactivity disorder (ADHD), the brain matures in a normal pattern but is delayed three years in some regions, on average, compared to youth without the disorder, an imaging study by researchers at the National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH) has revealed. The delay in ADHD was most prominent in regions at the front of the brain’s outer mantle (cortex), important for the ability to control thinking, attention and planning. Otherwise, both groups showed a similar back-to-front wave of brain maturation with different areas peaking in thickness at different times.

“Finding a normal pattern of cortex maturation, albeit delayed, in children with ADHD should be reassuring to families and could help to explain why many youth eventually seem to grow out of the disorder,” explained Philip Shaw, M.D., NIMH Child Psychiatry Branch, who led research team.

Previous brain imaging studies failed to detect the developmental lag because they focused on the size of the relatively large lobes of the brain. The sharp differences emerged only after a new image analysis technique allowed the researchers to pinpoint the thickening and thinning of thousands of cortex sites in hundreds of children and teens, with and without the disorder.

“If you’re just looking at the lobes, you have only four measures instead of 40,000,” explained Shaw. “You don’t pick up the focal, regional changes where this delay is most marked.”

Among 223 youth with ADHD, half of 40,000 cortex sites attained peak thickness at an average age of 10.5, compared to age 7.5 in a matched group of youth without the disorder.

Shaw, Judith Rapoport, M.D., of the NIMH Child Psychiatry Branch, Alan Evans, M.D., of McGill University, and colleagues report on their magnetic resonance imaging (MRI) study during the week of November 12, 2007, in the online edition of the Proceedings of the National Academy of Sciences.

The researchers scanned most of the 446 participants — ranging from preschoolers to young adults — at least twice at about three-year intervals. They focused on the age when cortex thickening during childhood gives way to thinning following puberty, as unused neural connections are pruned for optimal efficiency during the teen years.

In both ADHD and control groups, sensory processing and motor control areas at the back and top of the brain peaked in thickness earlier in childhood, while the frontal cortex areas responsible for higher-order executive control functions peaked later, during the teen years. These frontal areas support the ability to suppress inappropriate actions and thoughts, focus attention, remember things from moment to moment, work for reward, and control movement — functions often disturbed in people with ADHD.

Circuitry in the frontal and temporal (at the side of the brain) areas that integrate information from the sensory areas with the higher-order functions showed the greatest maturational delay in youth with ADHD. For example, one of the last areas to mature, the middle of the prefrontal cortex, lagged five years in those with the disorder.

The motor cortex emerged as the only area that matured faster than normal in the youth with ADHD, in contrast to the late-maturing frontal cortex areas that direct it. This mismatch might account for the restlessness and fidgety symptoms common among those with the disorder, the researchers suggested.

They also noted that the delayed pattern of maturation observed in ADHD is the opposite of that seen in other developmental brain disorders like autism, in which the volume of brain structures peak at a much earlier-than-normal age.

The findings support the theory that ADHD results from a delay in cortex maturation. In future studies, the researchers hope to find genetic underpinnings of the delay and ways of boosting processes of recovery from the disorder.

“Brain imaging is still not ready for use as a diagnostic tool in ADHD,” noted Shaw. “Although the delay in cortex development was marked, it could only be detected when a very large number of children with the disorder were included. It is not yet possible to detect such delay from the brain scans of just one individual. The diagnosis of ADHD remains clinical, based on taking a history from the child, the family and teachers.”

Also participating in the research were: Kristen Eskstrand, Wendy Sharp, Jonathan Blumenthal, Dede Greenstein, Liv Clasen, and Jay Giedd, M.D., NIMH.

The National Institute of Mental Health (NIMH) mission is to reduce the burden of mental and behavioral disorders through research on mind, brain, and behavior.

The gene that turns breast-milk into brain food

November 15th, 2007

From Nature News

Does breast-feeding a child boost its brain development and raise its intelligence? Only if the child carries a version of a gene that can harness the goodness of breast-milk, say researchers.

The results add to the nature versus nurture debate over intelligence, by showing how the two effects can interact.

The question of whether people are born intelligent or made intelligent by their environment has been debated for decades. Research with identical twins separated at birth has shown that both genetics and rearing conditions are important in determining intelligence.

One of the important environmental effects seems to be breast-feeding. Children who are breast-fed generally perform better in IQ tests than do those fed on other types of milk. Researchers think that this might be because specific fatty acids found in human milk, but not in cows milk or infant formulas, improve brain development.

Avshalom Caspi and Terrie Moffitt, psychologists at Kings College, London, and their colleagues looked at the relationship between breast-feeding and intelligence to explore the possibility that in this case nature and nurture might be intimately linked.

The group first looked for genes that metabolize fatty acids, which in turn are important for the growth of neurons. Differences in such genes, they hypothesized, might moderate the intellectual advantage associated with breast-feeding. They searched the literature and gene databases and found a good candidate: a gene called FADS2 .

Class test

The team then looked at more than 1,000 children in New Zealand who were born in 1972 and IQ tested at ages 7, 9, 11, and 13; a record was kept of which children had been breast-fed. The study was repeated with about 2,200 children in Britain who were born in 199495 and IQ tested at age 5. DNA tests were used to look at a specific spot in their FADS2 genes, to see which version or allele of the gene they carried.

In children who carried at least one copy of a C allele for FASD2 , those who were breast-fed generally had a higher IQ than those who were not: by an average of 6.4 IQ points in the New Zealand study, and by 7.0 IQ points in the British one. By contrast, children carrying two G alleles had roughly the same IQ irrespective of their diet. About 10% of the population is thought to be GG.

We had a very strong hypothesis, but it could easily have turned out wrong, so we were pleased when the data fit the hypothesis in New Zealand, and then really delighted when it was confirmed in Britain, says Moffitt. The team reports their findings in the Proceedings of the National Academy of Sciences 1.

Why and how this genetic difference came into being is unclear. It is almost as though the G allele evolved as a protective genotype for children who might not get enough breast-milk, says developmental psychologist Linda Gottfredson at the University of Delaware in Newark.

Mother care

The result will help to settle the debate over whether breast-feeding is linked to intelligence because of the nutritional quality of the milk, or because mothers who breast-feed are the sorts of mothers who encourage child learning. I think this research will settle that debate, or at the very least bring it near a close, says epidemiologist Jean Golding at the University of Bristol, UK.

Avshalom CaspiIt might also serve as a guide for researchers aiming to find the genetic factors that affect other complex developmental factors, such as height. Such studies are usually approached by scanning thousands of people in search for different alleles associated with the trait of interest. This research is suggesting that simply looking at huge samples may be missing the point, says psychologist and geneticist Matt McGue of the University of Minnesota in Twin Cities. He notes that using specific context clues, as was done in this study, is a more efficient way to look for a gene.

And the finding contributes to the growing feeling that scientists shouldnt think of nature or nurture acting in isolation from each other. Our team has reported geneenvironment interactions involved in depression, violence and psychosis … with these new data, many of us are starting to think that nature via nurture might be a better catch phrase, says Caspi.