 Language Is Not New to Newborns
Attention deficit is due to smaller brain, research suggests
BABIES CAN TELL LANGUAGE FROM NOISE
TOKYO
Babies can differentiate a language from noise at birth, suggesting either they learn it while in the womb, or humans have innate language skills, according to a joint study by Italian, Japanese, and French laboratories.
The study, which covered 12 Italian newborn babies aged two to five days and used speech samples from two Italian mothers whose infants did not participate in the experiment, was published September in the Proceedings of the US National Academy of Sciences.
The study used an optical topography device newly developed by Hitachi Ltd. to detect change in cerebral blood volume and oxygen saturation. The system uses near infrared rays and displays blood hemoglobin levels in the brain in different colors.
When exposed to normal, forward speech, the newborns showed a significantly greater activity in the left hemisphere of their brains than in the right hemisphere, according to the research. The left hemisphere is known to have connections with language processing. In contrast, no significant differences by hemisphere were observed during the playing of tapes of backward speech or silent conditions.
The study "provides the demonstration that the neonate brain responds specifically to normal speech only after a few hours of experience with speech signals outside the womb," the researchers said. The study "provides clear evidence that, at birth, the human brain is functionally organized to process speech in the left hemisphere, but not matched reversed utterances," they added.
A similar asymmetry by hemisphere is seen in adult brains, the study said. This "implies that humans are born with a brain organization geared to detect speech signals and pay attention to utterances produced by their surroundings."
The International School for Advanced Studies of Italy, the Hitachi Advanced Research Laboratory of Japan and France's National Center for Scientific Research and School of Advanced Studies in Social Sciences took part in the study.
VIRUS COMMON CAUSE OF JUVENILE DIABETES
HELSINKI
One of the main causes of juvenile or type 1 diabetes is infection brought on by an enterovirus, Finnish researchers said, citing results from a survey of 75,000 people conducted over nine years.
In Finland, one in 135 children is diagnosed with diabetes before reaching the age of 15, a rate that is several times higher than the world average. The Finnish research team undertook its work after noting that while a large number of Finns have a genetic predisposition to type 1 diabetes, only a small proportion of those with the predisposition end up suffering from the disease.
The team sought to find other causes that could lead to the high frequency of the disease in Finland. It found that, in addition to enterovirus infections, diet, vitamin D deficiency, and childhood obesity can also play a role in developing the condition.
A baby's exposure to cow's milk and certain types of grains during its first four months could also trigger Type 1 diabetes later in life, said one of the researchers, Helsinki University professor Mikael Knip.
Of the 75,000 Finns that participated in the survey, about 6,200 were genetically predisposed to diabetes, but only 100 have been diagnosed with the disease, Knip said.
Through screenings, the researchers have been able to identify 70 percent of those who have or who are likely to get the disease, he added.
ATTENTION DEFICIT PINNED TO BRAIN ABNORMALITIES
PARIS
Attention deficit hyperactivity disorder (ADHD), a little-understood condition that affects children, has been pinned to abnormalities in key parts of the brain's prefrontal cortex.
In the first large study to map cerebral areas that have been linked to ADHD, US doctors found that in children with this problem two parts of the brain known as the dorsal prefrontal and anterior temporal regions of the cortex were smaller than they should normally be.
Two other zones, known as enlarged posterior temporal and inferior parietal cortices, were larger. These are strongly inter-connected parts of the brain that help to process working memory, figure out time and inhibit impulses.
The findings suggest "this action-attentional network is anatomically disrupted in children who have attention-deficit hyperactivity disorder," the researchers report in The Lancet.
Twenty-seven children and adolescents diagnosed with ADHD took part in the study, and their brains were compared with those of 46 healthy counterparts.
Previous studies have suggested that there is a small reduction in brain volume, of between three and five percent, among children with ADHD compared with their counterparts. But this is the first large-scale research to use magnetic resonance imaging scanners to get an idea as to where, more precisely, the problem may lie.
ADHD is a recently-defined neuropsychiatric disorder. Children with it have trouble concentrating, keeping still and observing discipline, and often as a result do very poorly at school. Between three and six percent of American schoolchildren have this condition, according to the authors, led by Elizabeth Sowell, assistant professor of neurology at the University of California, Los Angeles.
The cause of ADHD is unclear, but the frequent method of treatment is psychostimulants, a class of powerful drugs that is a stimulant in adults but in children has a calming effect. These medications can also have big side effects.
One of the useful consequences of the latest research would be to fine-tune these drugs so that they can specifically target affected parts of the brain, said co-author Bradley Peterson, a professor of psychiatry at New York's Columbia University.
EXPERTS RUSH VACCINE FOR DEADLY ROTAVIRUS
MANILA
Health experts from around the world have pledged to boost surveillance and develop a vaccine against the little-known rotavirus, the common cause of diarrhea among children blamed for nearly half a million deaths yearly.
Vaccines being developed by private biomedical companies are now in their late-stages, World Health Organization representative to the Philippines Jean Marc Olive told a conference of disease experts in Manila in late October.
The conference was organized by the Asian Rotavirus Surveillance Network (ARSN), which is helping in the development of the vaccine, and the US Centers for Disease Control and Prevention (CDC) boost awareness of the rotavirus, listed as among the deadliest viruses in the world, that greatly affects developing countries.
However, Olive stressed there needed to be a stronger push to inform the public of the rotavirus, which causes severe dehydrating diarrhea among children. "In the Philippines, few physicians and policy makers... are aware of the importance of rotavirus, or even the name of the disease," he said.
"Even fewer might suspect that this disease could be prevented by vaccine within a few years," said Olive. "Rarely is the diagnosis ever made. Yet this common, almost nameless infection, touches every child born in this country and sends hundreds of thousands for treatment, tens of thousands to hospitals and several thousands to their graves each year."
Papers presented at the conference showed that rotavirus causes approximately 111 million episodes of gastroenteritis requiring home care, 25 million clinic visits, two million hospitalizations and an average of 440,000 deaths among children under five.
Children in poor countries account for about 82 percent of all deaths, and the high incidence of rotavirus "underscores the urgent need for interventions" including development of a vaccine, the documents showed.
There is, however, also a prevalence of the disease in highly developed or industrialized countries, indicating that improvements in water supply, hygiene, and sanitation are not enough to combat rotavirus.
"Among the many causes of childhood diarrhea, rotavirus is clearly the most important. It knows no national boundaries and infects children the world over," Health Secretary Manuel Dayrit said, noting that it also affects parents who have to take time off from work to care for their sick children.
"It is the diarrheal illness most likely to fail treatment with oral rehydration therapy because of the associated vomiting and inherent severity," he said. "And it will not go away with improvements in water, hygiene, and sanitation. New vaccines hold the key to prevention and control."
In 1998, Wyeth Laboratories developed Rotashield, the first rotavirus vaccine and licensed it in the United States for the routine immunization of infants. Nine months later, its use was suspended after complications were reported, eventually leading to a halt in production.
The vaccine had held "the promise of early relief to this killer," Dayrit said, noting that four million children have died in the long period between the withdrawal of that vaccine and the licensing of drugs still in clinical trials.
"We cannot wait to move our agenda forward," he said.
NIVERAPINE CONFERS PROTECTION TO NEWBORNS
PARIS
Nevirapine can provide a cheap, lasting shield to infants in poor countries who are at risk of catching the AIDS virus from their mother's breast milk.
A nevirapine trial involving Ugandan children found the vast majority of those who did not have HIV after birth and in their early weeks of life remained HIV-negative 18 months later.
"This simple, inexpensive, well-tolerated regimen has the potential to significantly decrease HIV-1 perinatal transmission in less-developed countries," the study said.
The trial, HIVNET 012, enrolled 637 mothers in Kampala from 1997 to 1999. The mothers were given either nevirapine or zidovudine at the onset of labor, and their baby was given a dose shortly after birth, while 19 were given placebos.
In 1999, the HIVNET 012 reported that the risks of HIV transmission to these infants were 8.1 percent (nevirapine) and 10.3 percent (zidovudine) at birth, which rose to 13.5 percent and 22.1 percent by the time they were 14 to 16 weeks old. In a follow-up study, they determined the risk at the age of 18 months stood at 15.7 percent for nevirapine and 25.8 percent for zidovudine.
In 2002, an estimated 800,000 children became infected with HIV through mother-to-child transmission. More than 90 percent lived in developing countries.
Giving the mother the drug at the start of labor, and to the child for a short period postnatally, is believed to reduce the risk of HIV during delivery and through breast feeding.
AIDS campaigners say this technique is inexpensive and simple to administer-a vital factor in countries where people may live in remote rural areas where there is no access to follow-up care.
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