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This study documented that autistic children experience behavior changes during fever.

Einstein researchers contend that scientific evidence directly points to the locus coeruleus–noradrenergic (LC-NA) system as being involved in autism. "The LC-NA system is the only brain system involved both in producing fever and controlling behavior," says co-author Dominick P. Purpura, M.D., dean emeritus and distinguished professor of neuroscience at Einstein.

The locus coeruleus has widespread connections to brain regions that process sensory information. It secretes most of the brain's noradrenaline, a neurotransmitter that plays a key role in arousal mechanisms, such as the "fight or flight" response. It is also involved in a variety of complex behaviors, such as attentional focusing (the ability to concentrate attention on environmental cues relevant to the task in hand, or to switch attention from one task to another). Poor attentional focusing is a defining characteristic of autism.

"What is unique about the locus coeruleus is that it activates almost all higher-order brain centers that are involved in complex cognitive tasks," says Dr. Mehler.

autism, the LC-NA system is dysregulated by the interplay of environment, genetic, and epigenetic factors

They believe that stress plays a central role in dysregulation of the LC-NA system, especially in the latter stages of prenatal development when the fetal brain is particularly vulnerable.

a higher incidence of autism among children whose mothers had been exposed to hurricanes and tropical storms during pregnancy.

autistic children, fever stimulates the LC-NA system, temporarily restoring its normal regulatory function. "This could not happen if autism was caused by a lesion or some structural abnormality of the brain," says Dr. Purpura.

future of autism treatment probably lies in drugs that selectively target certain types of noradrenergic brain receptors or, more likely, in epigenetic therapies targeting genes of the LC-NA system.

If the locus coeruleus is impaired in autism, it is probably because tens or hundreds, maybe even thousands, of genes are dysregulated in subtle and complex ways," says Dr. Mehler. "The only way you can reverse this process is with epigenetic therapies, which, we are beginning to learn, have the ability to coordinate very large integrated gene networks."

"You can't take a complex neuropsychiatric disease that has escaped our understanding for 50 years and in one fell swoop have a therapy that is going to reverse it — that's folly. On the other hand, we now have clues to the neurobiology, the genetics, and the epigenetics of autism. To move forward, we need to invest more money in basic science to look at the genome and the epigenome in a more focused way."

An initial retrospective study is comparing two groups of 20 children initially diagnosed with autism who were functioning well after two or more years of treatment, either with a discrete trial training approach or the DIR approach. The study aims to determine if treatment differences lead to subtle differences in outcome, for example, in terms of flexibility, emotional range, creativity and richness of the child's inner life. Investigators are planning to follow this research with a prospective, randomized, more rigorous study of the two approaches.

"In our previous studies we found out that it looks like you can't just deliver a standard treatment to autistic kids, that there's so much variability among the children that what works for one child doesn't work for another child," he says. "Our hypothesis is that...unless you individualize treatment, you're not going to get the best effect."

Researchers at the University of Maryland are testing an intervention to trigger children's "social engagement system," which includes behaviors such as listening, looking, facial expressions and vocalizations that support social interaction, says psychologist Stephen Porges, PhD. The treatment is designed to improve autistic children's ability to interact with others, thereby making them more receptive to traditional therapies.

The intervention is based on the theory that tensing the middle ear muscles enables people to pick out the human voice from lower frequency sounds in the environment, Porges says. Treatment involves exercising middle ear muscles by playing music that has been altered to include only frequencies associated with the human voice, which improves one's ability to listen to human voices. This, in turn, stimulates the entire social engagement system, Porges says. About 80 percent of 50 children with autism or other behavioral problems receiving this treatment via five 45-minute sessions in a double blind, randomized controlled study showed marked improvements in listening, language and other communication skills.

In a report last year in the Journal of Autism and Developmental Disorders (Vol. 28, No. 1, p. 15-23) evaluating an intensive home-based discrete trial training intervention, Stephen Sheinkopf, PhD, of the University of Miami and Bryna Siegel, PhD, of the University of California, San Francisco, noted that children receiving an average of only 21 hours per week of treatment showed gains in IQ comparable to those achieved by children receiving 32 hours per week. The intensity question remains an issue of importance for the autism community. "If we need 40 hours a week, fine," says psychologist Geraldine Dawson, PhD, of the University of Washington. "But if you only need 25, you have to realize that 40 hours is a tremendous burden not only financially, but on families and on the child."

Nonetheless, this incidence is about 100 times greater than the rate at which autism affects unrelated people in the population.

One study showed that the likelihood that the identical twin of an autistic child also would be autistic was 82 percent, whereas the equivalent rate for fraternal twins was only 10 percent.

With sophisticated statistical techniques and numerous twin studies, behavioral geneticists now believe that as much as 90 percent of the behavioral phenotype of autism is related to inherited genes.

Antivaccine activists are campaigning among them, which worries public health officials, especially because some families go back and forth to Somalia, where measles is still a significant cause of childhood death, according to Unicef.

Last year, she said, 25 percent of the children in preschool classes offering the most intensive treatment had Somali parents, while only about 6 percent of public school enrollment is Somali. Dr. Daniel S. McLellan, a pediatrician, said that when he began practicing at Children’s Hospital six years ago, he was struck by how many autistic Somali children he saw.

Clinically, I was also intrigued by the high rates of vision problems found among the ASD group. Although, as I mentioned, this may be due to a self-selection of the parents who agreed to participate, this is consistent with data suggesting that children with developmental disorders are more likely to have visual problems than typically developing children

Einstein researchers contend that scientific evidence directly points to the locus coeruleus–noradrenergic (LC-NA) system as being involved in autism. “The LC-NA system is the only brain system involved both in producing fever and controlling behavior,” says co-author Dominick P. Purpura, M.D., dean emeritus and distinguished professor of neuroscience at Einstein.

The locus coeruleus has widespread connections to brain regions that process sensory information.

It is also involved in a variety of complex behaviors, such as attentional focusing (the ability to concentrate attention on environmental cues relevant to the task in hand, or to switch attention from one task to another).

“What is unique about the locus coeruleus is that it activates almost all higher-order brain centers that are involved in complex cognitive tasks,” says Dr. Mehler.

Drs. Purpura and Mehler hypothesize that in autism, the LC-NA system is dysregulated by the interplay of environment, genetic, and epigenetic factors (chemical substances both within as well as outside the genome that regulate the expression of genes). They believe that stress plays a central role in dysregulation of the LC-NA system, especially in the latter stages of prenatal development when the fetal brain is particularly vulnerable.

Drs. Purpura and Mehler believe that, in autistic children, fever stimulates the LC-NA system, temporarily restoring its normal regulatory function.

the future of autism treatment probably lies in drugs that selectively target certain types of noradrenergic brain receptors or, more likely, in epigenetic therapies targeting genes of the LC-NA system.

“You can’t take a complex neuropsychiatric disease that has escaped our understanding for 50 years and in one fell swoop have a therapy that is going to reverse it — that’s folly. On the other hand, we now have clues to the neurobiology, the genetics, and the epigenetics of autism. To move forward, we need to invest more money in basic science to look at the genome and the epigenome in a more focused way.”