Autism: Conventional UK police interview techniques are not effective

Police find interviewing and interacting with witnesses and suspects with autism a real challenge, a new study from researchers in the Department of Psychology at UK's University of Bath, has revealed, highlighting that the ways UK police officers have been taught to interview could be at odds with what is needed in these situations.

As part of the study, the researchers found that existing interview techniques tend to focus on open questions, only later narrowing down to closed questions, whereas research shows that people with autism may need focused questions from the outset.

The Economic and Social Research Council (ESRC)-funded research studied what does, and does not, work when police interview people with autism.

Katie Maras

The researchers, including Dr Katie Maras from Department of Psychology, University of Bath and her colleague, Dr Laura Crane, at City University London, are calling for better training for UK police and criminal justice professionals as, at present in the UK, these groups currently have no standard compulsory training about autism.

Dr Maras said: "As part of this study we have heard of many cases where problems have arisen because police and other criminal justice professionals know very little about autism.

"Research in this area is still in its infancy, but it's steadily accumulating. There's a crucial need to get findings to practitioners to help them obtain the best evidence possible from people with autism."

Laura Crane

More than 400 UK frontline and investigative police officers holding a variety of ranks provided information for the study.

They spoke of the difficulties and challenges they encounter when obtaining written, oral and identification evidence.

Officers reported, for example, finding it hard to build rapport with people with autism, which usually plays an important part in interviews.

They also described difficulties in arranging a suitable environment for interviews.

"Police stations tend to be noisy with bright or flickering lighting and strange smells, but people with autism are often sensitive to sensory input and as a result they can struggle to maintain concentration in interviews", Dr Maras added.

Over 600,000 people in the UK have autism, many of whom will come into contact with the police at some point in their lives.

Poor social-communication skills can make them vulnerable when involved with the UK Criminal Justice System as a victim, witness or suspect.

Individuals with autism process memories in a different way from other people, which can lead to misunderstandings.

During the study, officers answered questions about existing interview practices that they considered worked well, and were asked what could be done to develop understanding and skills.

The researchers found examples of excellent practice, especially among police officers who were able to draw on their personal experience of the disorder through familiarity with a family member or colleague with autism.

On a further positive note, related research shows that there are simple and effective strategies that can enhance the evidence that people with autism give and improve their credibility as witnesses.

For example, providing information about a witness' diagnosis can improve his or her perceived credibility; unusual and stereotyped behaviours can be attributed to autism, rather than a lack of credibility.

Rett syndrome: Autism Spectrum Disorder Mice improve with synthetic oil

When young mice with the rodent equivalent of a rare autism spectrum disorder (ASD), called Rett syndrome, were fed a diet supplemented with the synthetic oil triheptanoin, they lived longer than mice on regular diets.

Importantly, their physical and behavioral symptoms were also less severe after being on the diet, according to results of new research from The Johns Hopkins University.

Researchers involved in the study think that triheptanoin improved the functioning of mitochondria, energy factories common to all cells.

Since mitochondrial defects are seen in other ASDs, the researchers say, the experimental results offer hope that the oil could help not just people with Rett syndrome, but also patients with other, more common ASDs.

A description of the research will be published on Oct. 9 in the journal PLOS ONE.

ASDs affect an estimated one in 68 children under 8 years of age in the United States. Rett syndrome is a rare ASD caused by mutations in the MECP2 gene, which codes for methyl-CpG-binding-protein 2 (MeCP2).

Rett syndrome includes autism-like signs, such as difficulty communicating, socializing and relating to others.

Other hallmarks are seizures, decreased muscle tone, repetitive involuntary movements, and gastrointestinal and breathing problems.

These other signs are also seen in some patients with other ASDs, suggesting underlying similarities in their causes.

While the causes of most ASDs are unknown and thought to be complex, Rett syndrome is unique, and could be a source of insight for the others, because it is caused by an error in a single gene.

The research team used mice lacking the MeCP2 protein, which left them with severe Rett syndrome.

In examining those mice, what stood out, according to Gabriele Ronnett, M.D., Ph.D., who led the research project at the Johns Hopkins University School of Medicine, was that they weighed the same as healthy mice but had large fat deposits accompanied by lower amounts of nonfat tissue, such as muscle.

This suggested that calories were not being used to support normal tissue function but instead were being stored as fat.

This possibility led Ronnett and her research team to consider the role of mitochondria, which transform the building blocks of nutrients into a high-energy molecule, ATP.

This molecule drives processes such as the building of muscle and the growth of nerve cells.

Mitochondria use a series of biochemical reactions, collectively called the TCA cycle, to make this transformation possible.

According to Susan Aja, Ph.D., a research associate and lead member of the research team, "If the components of the TCA cycle are low, nutrient building blocks are not processed well to create ATP. They are instead stored as fat."

Ronnett suspected, she says, that some of Rett syndrome's neurological symptoms could stem from metabolic deficiencies caused by faulty mitochondria and reduced energy for brain cells.

"Rett syndrome becomes apparent in humans 6 to 18 months old, when the energy needs of the brain are particularly high, because a lot of new neural connections are being made," says Ronnett.

"If the mitochondria are already defective, stressed or damaged, the increased demand would be too much for them."

Previous small clinical trials in people with a different metabolic disorder suggested that dietary intervention with triheptanoin could help.

Triheptanoin is odourless, tasteless and a little thinner than olive oil. It is easily processed to produce one of the components of the TCA cycle.

When Rett syndrome mice were weaned at 4 weeks of age, they were fed a diet in which 30 percent of their calories came from triheptanoin, mixed in with their normal pelleted food.

Though far from a cure, the results of the triheptanoin treatment were impressive, the researchers say.

Treated mice had healthier mitochondria, improved motor function, increased social interest in other mice and lived four weeks, or 30 percent, longer than mice who did not receive the oil. The team also found that the diet normalized their body fat, glucose and fat metabolism.

"You can think of the mitochondria of the Rett syndrome model mice as damaged buckets with holes in them that allow TCA cycle components to leak out," says Aja.

"We haven't figured out how to plug the holes, but we can keep the buckets full by providing triheptanoin to replenish the TCA cycle."

"It is still too early to assume that this oil will work in humans with ASDs, but these results give us hope," says Ronnett.

"It's exciting to think that we might be able to improve many ASDs without having to identify each and every contributing gene."

According to Aja, additional mouse studies are needed to learn if female mice respond to the treatment, to perform a wider range of physiology and behavior tests, and, importantly, to assess the effects of triheptanoin treatment on the brain, which is considered the main driver of many Rett symptoms.

The team would also like to provide triheptanoin at earlier ages, perhaps via the mothers' milk, to mimic developmental ages at which most children are diagnosed with Rett syndrome.

Triheptanoin is currently made for research purposes only and is not available as a medicine or dietary supplement for humans.

More information: PLOS ONE: dx.plos.org/10.1371/journal.pone.0109527

EEG Brainwave test could improve autism diagnosis and classification

A new study by researchers at Albert Einstein College of Medicine of Yeshiva University suggests that measuring how fast the brain responds to sights and sounds could help in objectively classifying people on the autism spectrum and may help diagnose the condition earlier.

The paper was published today in the online edition of the Journal of Autism and Developmental Disabilities.

The U.S. Centers for Disease Control and Prevention estimates that 1 in 68 children has been identified with an autism spectrum disorder (ASD).

The signs and symptoms of ASD vary significantly from person to person, ranging from mild social and communication difficulties to profound cognitive impairments.

"One of the challenges in autism is that we don't know how to classify patients into subgroups or even what those subgroups might be," said study leader Sophie Molholm, Ph.D., associate professor in the Dominick P. Purpura Department of Neuroscience and the Muriel and Harold Block Faculty Scholar in Mental Illness in the department of pediatrics at Einstein.

"This has greatly limited our understanding of the disorder and how to treat it."

Autism is diagnosed based on a patient's behavioural characteristics and symptoms.

"These assessments can be highly subjective and require a tremendous amount of clinical expertise," said Dr. Molholm. "We clearly need a more objective way to diagnose and classify this disorder."

An earlier study by Dr. Molholm and colleagues suggested that brainwave electroencephalogram (EEG) recordings could potentially reveal how severely ASD individuals are affected.

That study found that children with ASD process sensory information, such as sound, touch and vision, less rapidly than typically developing children do.

The current study was intended to see whether sensory processing varies along the autism spectrum. Forty-three ASD children aged 6 to 17 were presented with either a simple auditory tone, a visual image (red circle), or a tone combined with an image, and instructed to press a button as soon as possible after hearing the tone, seeing the image or seeing and hearing the two stimuli together.

Continuous EEG recordings were made via 70 scalp electrodes to determine how fast the children's brains were processing the stimuli.

The speed with which the subjects processed auditory signals strongly correlated with the severity of their symptoms: the more time required for an ASD individual to process the auditory signals, the more severe that person's autistic symptoms.

"This finding is in line with studies showing that, in people with ASD, the microarchitecture in the brain's auditory center differs from that of typically developing children," Dr. Molholm said.

The study also found a significant though weaker correlation between the speed of processing combined audio-visual signals and ASD severity. No link was observed between visual processing and ASD severity.

"This is a first step toward developing a biomarker of autism severity, an objective way to assess someone's place on the ASD spectrum," said Dr. Molholm.

"Using EEG recordings in this way might also prove useful for objectively evaluating the effectiveness of ASD therapies."

In addition, EEG recordings might help diagnose ASD earlier. "Early diagnosis allows for earlier treatment, which we know increases the likelihood of a better outcome," said Dr. Molholm.

"But currently, fewer than 15 percent of children with ASD are diagnosed before age 4. We might be able to adapt this technology to allow for early ASD detection and therapy for a much larger percentage of children."

More information: The paper is titled "Neurophysiological Indices of Atypical Auditory Processing and Multisensory Integration are Associated with Symptom Severity in Autism."

Children with autism have extra synapses in brain

In a study of brains from children with autism, researchers found that autistic brains did not undergo normal pruning during childhood and adolescence. 

The images show representative neurons from autistic (left) and control (right) brains; the spines on the neurons indicate the location of synapses.

Credit: Guomei Tang, PhD and Mark S. Sonders, PhD/Columbia University Medical Center

Children and adolescents with autism have a surplus of synapses in the brain, and this excess is due to a slowdown in a normal brain "pruning" process during development, according to a study by neuroscientists at Columbia University Medical Center (CUMC).

Because synapses are the points where neurons connect and communicate with each other, the excessive synapses may have profound effects on how the brain functions.

The study was published in the August 21 online issue of the journal Neuron.

A drug that restores normal synaptic pruning can improve autistic-like behaviors in mice, the researchers found, even when the drug is given after the behaviours have appeared.

"This is an important finding that could lead to a novel and much-needed therapeutic strategy for autism," said Jeffrey Lieberman, MD, Lawrence C. Kolb Professor and Chair of Psychiatry at CUMC and director of New York State Psychiatric Institute, who was not involved in the study.

Although the drug, rapamycin, has side effects that may preclude its use in people with autism, "the fact that we can see changes in behaviour suggests that autism may still be treatable after a child is diagnosed, if we can find a better drug," said the study's senior investigator, David Sulzer, PhD, professor of neurobiology in the Departments of Psychiatry, Neurology, and Pharmacology at CUMC.

David Sulzer

During normal brain development, a burst of synapse formation occurs in infancy, particularly in the cortex, a region involved in autistic behaviours; pruning eliminates about half of these cortical synapses by late adolescence.

Synapses are known to be affected by many genes linked to autism, and some researchers have hypothesized that people with autism may have more synapses.

To test this hypothesis, co-author Guomei Tang, PhD, assistant professor of neurology at CUMC, examined brains from children with autism who had died from other causes.

Thirteen brains came from children ages two to 9, and thirteen brains came from children ages 13 to 20. Twenty-two brains from children without autism were also examined for comparison.

Dr. Tang measured synapse density in a small section of tissue in each brain by counting the number of tiny spines that branch from these cortical neurons; each spine connects with another neuron via a synapse.

By late childhood, she found, spine density had dropped by about half in the control brains, but by only 16 percent in the brains from autism patients.

"It's the first time that anyone has looked for, and seen, a lack of pruning during development of children with autism," Dr. Sulzer said, "although lower numbers of synapses in some brain areas have been detected in brains from older patients and in mice with autistic-like behaviours."


Clues to what caused the pruning defect were also found in the patients' brains; the autistic children's brain cells were filled with old and damaged parts and were very deficient in a degradation pathway known as "autophagy."

Cells use autophagy (a term from the Greek for self-eating) to degrade their own components. Using mouse models of autism, the researchers traced the pruning defect to a protein called mTOR.

When mTOR is overactive, they found, brain cells lose much of their "self-eating" ability and without this ability, the brains of the mice were pruned poorly and contained excess synapses.

"While people usually think of learning as requiring formation of new synapses, "Dr. Sulzer says, "the removal of inappropriate synapses may be just as important."

The researchers could restore normal autophagy and synaptic pruning, and reverse autistic-like behaviors in the mice, by administering rapamycin, a drug that inhibits mTOR.

The drug was effective even when administered to the mice after they developed the behaviors, suggesting that such an approach may be used to treat patients even after the disorder has been diagnosed.

Because large amounts of overactive mTOR were also found in almost all of the brains of the autism patients, the same processes may occur in children with autism.

"What's remarkable about the findings," said Dr. Sulzer, "is that hundreds of genes have been linked to autism, but almost all of our human subjects had overactive mTOR and decreased autophagy, and all appear to have a lack of normal synaptic pruning.

This says that many, perhaps the majority, of genes may converge onto this mTOR/autophagy pathway, the same way that many tributaries all lead into the Mississippi River.

Overactive mTOR and reduced autophagy, by blocking normal synaptic pruning that may underlie learning appropriate behaviour, may be a unifying feature of autism."

Alan Packer, PhD, senior scientist at the Simons Foundation, which funded the research, said the study is an important step forward in understanding what's happening in the brains of people with autism.

"The current view is that autism is heterogeneous, with potentially hundreds of genes that can contribute."

"That's a very wide spectrum, so the goal now is to understand how those hundreds of genes cluster together into a smaller number of pathways; that will give us better clues to potential treatments," he said.

"The mTOR pathway certainly looks like one of these pathways. It is possible that screening for mTOR and autophagic activity will provide a means to diagnose some features of autism, and normalizing these pathways might help to treat synaptic dysfunction and treat the disease."

Journal Reference: 
Guomei Tang, Kathryn Gudsnuk, Sheng-Han Kuo, Marisa L. Cotrina, Gorazd Rosoklija, Alexander Sosunov, Mark S. Sonders, Ellen Kanter, Candace Castagna, Ai Yamamoto, Zhenyu Yue, Ottavio Arancio, Bradley S. Peterson, Frances Champagne, Andrew J. Dwork, James Goldman, David Sulzer. "Loss of mTOR-Dependent Macroautophagy Causes Autistic-like Synaptic Pruning Deficits." Neuron, 2014; DOI: 10.1016/j.neuron.2014.07.040

Autism: ASU experts follow gut reaction in digestion treatment study

Clostridium difficile in the gut. The overgrowth of this dangerous bacteria can cause serious, life-threatening infections. 

About half of all children and adults with autism suffer from chronic gastrointestinal problems, causing frequent pain, discomfort and irritability.

Research out of Arizona State University suggests these gastrointestinal (GI) complications may be due, in part, to abnormal gut bacteria.

A new study approved by the U.S. Food and Drug Administration and led by Arizona State University will examine a novel treatment, called fecal microbiota transplant (FMT), for GI problems in children with autism.

The treatment involves transferring about 1,000 different species of live gut bacteria from a healthy donor that then act like a broad-spectrum probiotic treatment to restore normal gut bacteria.

FMT has been used to treat serious Clostrium difficle infections that kill up to 15,000 people each year in the United States.

Determining the safety and tolerability of using FMT to treat GI problems in children with autism is driving the study.

The FDA has approved a pilot treatment study of 20 children with autism, ages 7 to 17 years, and moderate to severe gastrointestinal problems.

Missing bacteria
Led by professor Rosa Krajmalnik-Brown, an expert on evaluating the composition of gut bacterial communities, and professor James Adams, director of the ASU Autism/Asperger's Research Program, the ASU research team published a scientific paper last year demonstrating that children with autism were missing several hundred species of gut bacteria compared to typical children.

"Our initial work found major differences in the gut bacteria of children with autism compared to typical children, and our subsequent work has confirmed those findings," said Krajmalnik-Brown.

"Children with autism seem to be missing hundreds of beneficial gut bacteria."

"Many children and adults with autism have chronic gut problems, sometimes lasting for many years and seriously affecting their quality of life," said Adams. "We think this treatment may be helpful."

The team's hypothesis is that FMT will "reseed" the gut with beneficial bacteria that will help diminish GI problems and possibly reduce autistic symptoms.

Several studies show that FMT may also be helpful in treating other GI problems, such as ulcerative colitis, Crohn's disease, inflammatory bowel disease, irritable bowel syndrome and chronic constipation.

Beneficial versus harmful
The human gut typically contains more than 1,000 different species of bacteria – most of them beneficial.

These bacteria help with digesting food, making certain vitamins, improving GI function and protecting against pathogenic bacteria.

However, there are a few dangerous bacteria, such as Clostidium difficile (C. difficile), which can cause serious, life-threatening infections.

C. difficile kills about 15,000 people per year in the U.S., but a single dose of FMT has been shown to cure C. difficile with 92 percent effectiveness, usually within a few days.

Collaborating with Northern Arizona University and University of Arizona, the ASU team will lead the treatment portion of the study, with the help of Sharon McDonough-Means, a developmental pediatrician involved in the care of children with autism and previous research studies.

Greg Caporaso at NAU, an expert in computational and statistical methods for studying communities of microorganisms, will analyze the effect of FMT on gut bacterial communities, and Matthew Sullivan at UA will investigate the viruses that infect gut bacteria, and thereby affect bacterial populations in the gut.

The new initiative is a follow-up to a previous study that demonstrated that treatment with a powerful oral antibiotic, vancomycin, led to a temporary improvement in both gut symptoms and symptoms of autism, presumably because it killed off harmful bacteria in the gut.

However, when the treatment was stopped, the benefits were lost, presumably because there was insufficient "reseeding" of the gut with beneficial bacteria.

Children with Autism: Blood-oxytocin levels in normal range

Spacefilling model of oxytocin. Created using ACD/ChemSketch 8.0, ACD/3D Viewer and The GIMP. 

Credit: Wikipedia.

Autism does not appear to be solely caused by a deficiency of oxytocin, but the hormone's universal ability to boost social function may prove useful in treating a subset of children with the developmental disorder, according to new findings from the Stanford University School of Medicine and Lucile Packard Children's Hospital Stanford.

Low levels of oxytocin, a hormone involved in social functioning, have for years been suspected of causing autism. Prior research seeking a link has produced mixed results.

Now, in the largest-ever study to test the purported connection, the range of blood oxytocin levels has been shown to be the same in children with autism as that observed in two comparison groups: children with autistic siblings and children without autistic siblings.

In other words, similar numbers of children with low, medium and high oxytocin levels were found in all three groups.

A paper describing the new findings will be published online Aug. 4 in Proceedings of the National Academy of Sciences (PNAS).

Although autism was not directly linked to oxytocin deficiency, the Stanford team found that higher oxytocin levels were linked to better social functioning in all groups.

All children with autism have social deficits, but in the study these deficits were worst in those with the lowest blood oxytocin and mildest in those with the highest oxytocin.

In the comparison groups, children's social skills also fell across a range that correlated to their oxytocin levels.

"Oxytocin appears to be a universal regulator of social functioning in humans," said Karen Parker, PhD, assistant professor of psychiatry and behavioural sciences and the lead author of the study.

"That encompasses both typically developing children as well as those with the severe social deficits we see in children with autism."

Autism is a developmental disorder that affects 1 of every 68 children in the United States. It is characterised by social and communication deficits, repetitive behaviours and sensory problems.

The new study included 79 children with autism, 52 of their unaffected siblings and 62 unrelated children without autism. All of the children were between the ages of 3 and 12.

"It didn't matter if you were a typically developing child, a sibling or an individual with autism: Your social ability was related to a certain extent to your oxytocin levels, which is very different from what people have speculated," said Antonio Hardan, MD, professor of psychiatry and behavioural sciences and the study's senior author.

Hardan is a child and adolescent psychiatrist who treats children with autism at the hospital.

"The previous hypotheses saying that low oxytocin was linked to autism were maybe a little bit simplistic," he said.

"It's much more complex: Oxytocin is a vulnerability factor that has to be accounted for, but it's not the only thing leading to the development of autism."

The researchers caution, however, that blood oxytocin measurements may be different than oxytocin levels in the cerebrospinal fluid bathing the brain, which they did not measure.

In addition to examining blood oxytocin levels, the researchers examined the importance of small variations in the gene coding for the oxytocin receptor.

Certain receptor variants were correlated to higher scores on standard tests of social ability, the study found.

The team also discovered that blood levels of oxytocin are highly heritable: The levels are influenced by inheritance to about the same degree as adult height, which is often described as being strongly influenced by genetics.

"What our study hints at is that social function may be heritable in families," Parker said.

The study will help to guide future research to determine whether oxytocin is a useful autism treatment.

The study's findings suggest that some children with autism, such as the subset of kids with autism who have naturally low oxytocin levels, or those with oxytocin receptor gene variants associated with worse social functioning, might benefit most from oxytocin-like drugs.

"Autism is so heterogeneous," Parker said. "If we can identify biomarkers that help us identify the patients most likely to benefit from a specific therapy, we expect that will be very useful."

More information: "Plasma oxytocin concentrations and OXTR polymorphisms predict social impairments in children with and without autism spectrum disorder," by Karen J. Parker et al. PNAS, www.pnas.org/cgi/doi/10.1073/pnas.1402236111

Common gene variants account for most genetic risk for autism

The bulk of risk, or liability, for autism spectrum disorders was traced to inherited variations in the genetic code shared by many people. 

These and other (unaccounted) factors dwarfed contributions from rare inherited, non-additive and spontaneous (de novo) genetic factors 

Credit: Population-Based Autism Genetics and Environment Study

Most of the genetic risk for autism comes from versions of genes that are common in the population rather than from rare variants or spontaneous glitches, researchers funded by the National Institutes of Health (NIH) have found.

Heritability also outweighed other risk factors in this largest study of its kind to date. About 52 percent of the risk for autism was traced to common and rare inherited variation, with spontaneous mutations contributing a modest 2.6 percent of the total risk.

"Genetic variation likely accounts for roughly 60 percent of the liability for autism, with common variants comprising the bulk of its genetic architecture," explained Joseph Buxbaum, Ph.D., of the Icahn School of Medicine at Mount Sinai (ISMMS), New York City.

"Although each exerts just a tiny effect individually, these common variations in the genetic code add up to substantial impact, taken together."

Buxbaum, and colleagues of the Population-Based Autism Genetics and Environment Study (PAGES) Consortium, report on their findings in a unique Swedish sample in the journal Nature Genetics, July 20, 2014.

"Thanks to the boost in statistical power that comes with ample sample size, autism geneticists can now detect common as well as rare genetic variation associated with risk," said Thomas R. Insel, M.D., director of the NIH's National Institute of Mental Health (NIMH).

"Knowing the nature of the genetic risk will reveal clues to the molecular roots of the disorder. Common variation may be more important than we thought."

Although autism is thought to be caused by an interplay of genetic and other factors, including environmental, consensus on their relative contributions and the outlines of its genetic architecture has remained elusive.

Recently, evidence has been mounting that genomes of people with autism are prone to harboring rare mutations, often spontaneous, that exert strong effects and can largely account for particular cases of disease.

More challenging is to gauge the collective impact on autism risk of numerous variations in the genetic code shared by most people, which are individually much subtler in effect.

Limitations of sample size and composition made it difficult to detect these effects and to estimate the relative influence of such common, rare inherited, and rare spontaneous variation.

Differences in methods and statistical models also resulted in sometimes wildly discrepant estimates of autism's heritability, ranging from 17 to 50 percent.

Meanwhile, recent genome-wide studies of schizophrenia have achieved large enough sample sizes to reveal involvement of well over 100 common gene variants in that disorder.

These promise improved understanding of the underlying biology, and even development of risk-scores, which could help predict who might benefit from early interventions to nip psychotic episodes in the bud.

With their new study, autism genetics is beginning to catch up, say the researchers. It was made possible by Sweden's universal health registry, which allowed investigators to compare a very large sample of about 3,000 people with autism with matched controls.

Researchers also brought to bear new statistical methods that allowed them to more reliably sort out the heritability of the disorder.

In addition, they were able to compare their results with a parallel study in 1.6 million Swedish families, which took into account data from twins and cousins, and factors like age of the father at birth and parents' psychiatric history.

A best-fit statistical model took form, based mostly on combined effects of multiple genes and non-shared environmental factors.

"This is a different kind of analysis than employed in previous studies," explained Thomas Lehner, Ph.D., chief of NIMH's Genomics Research Branch.

"Data from genome-wide association studies was used to identify a genetic model instead of focusing just on pinpointing genetic risk factors. The researchers were able to pick from all of the cases of illness within a population-based registry."

Now that the genetic architecture is better understood, the researchers are identifying specific genetic risk factors detected in the sample, such as deletions and duplications of genetic material and spontaneous mutations.

Even though such rare spontaneous mutations accounted for only a small fraction of autism risk, the potentially large effects of these glitches makes them important clues to understanding the molecular underpinnings of the disorder, say the researchers.

"Within a given family, the mutations could be a critical determinant that leads to the manifestation of ASD in a particular family member," said Buxbaum.

"The family may have common variation that puts it at risk, but if there is also a de novo [spontaneous} mutation on top of that, it could push an individual over the edge."

"So for many families, the interplay between common and spontaneous genetic factors could be the underlying genetic architecture of the disorder."

More information: Gaughler T, Klei L, Sanders SJ, Bodea CA, Goldberg AP, Lee AB, Mahajan M, Manaa D, Pawitan Y, Reichert J, Ripke S, Sandin S, Sklar P, Svantesson O, Reichenberg A, Hultman CH, Devlin B, Roeder K, Buxbaum JD. Most genetic risk for autism resides with common variation. Nature Genetics, July 20, 2014. dx.doi.org/10.1038/ng.3039

Children with autism have elevated levels of steroid hormones in the womb

Scientists from the University of Cambridge and the Statens Serum Institute in Copenhagen, Denmark have discovered that children who later develop autism are exposed to elevated levels of steroid hormones (for example testosterone, progesterone and cortisol) in the womb.

The finding may help explain why autism is more common in males than females, but should not be used to screen for the condition.

Funded by the Medical Research Council (MRC), the results are published today in the journal Molecular Psychiatry.

The team, led by Professor Simon Baron-Cohen and Dr Michael Lombardo in Cambridge and Professor Bent Nørgaard-Pedersen in Denmark, utilized approximately 19,500 amniotic fluid samples stored in a Danish biobank from individuals born between 1993-1999.

Amniotic fluid surrounds the baby in the womb during pregnancy and is collected when some women choose to have an amniocentesis around 15-16 weeks of pregnancy.

This coincides with a critical period for early brain development and sexual differentiation, and thus allows scientists access into this important window in fetal development.

The researchers identified amniotic fluid samples from 128 males later diagnosed with an autism spectrum condition and matched these up with information from a central register of all psychiatric diagnoses in Denmark.

Within the amniotic fluid the researchers looked at 4 key 'sex steroid' hormones that are each synthesized, step-by-step from the preceding one, in the 'Δ4 sex steroid' pathway: progesterone, 17α-hydroxy-progesterone, androstenedione and testosterone.

They also tested the steroid hormone cortisol that lies outside this pathway. The researchers found that levels of all steroid hormones were highly associated with each other and most importantly, that the autism group on average had higher levels of all steroid hormones, compared to a typically developing male comparison group.

Professor Baron-Cohen said: "This is one of the earliest non-genetic biomarkers that has been identified in children who go on to develop autism."

"We previously knew that elevated prenatal testosterone is associated with slower social and language development, better attention to detail, and more autistic traits."

"Now, for the first time, we have also shown that these steroid hormones are elevated in children clinically diagnosed with autism."

"Because some of these hormones are produced in much higher quantities in males than in females, this may help us explain why autism is more common in males."

He added: "These new results are particularly striking because they are found across all the subgroups on the autism spectrum, for the first time uniting those with Asperger Syndrome, classic autism, or Pervasive Developmental Disorder Not-Otherwise-Specified. We now want to test if the same finding is found in females with autism."

Dr Michael Lombardo said: "This result potentially has very important implications about the early biological mechanisms that alter brain development in autism and also pinpoints an important window in fetal development when such mechanisms exert their effects."

Steroid hormones are particularly important because they exert influence on the process of how instructions in the genetic code are translated into building proteins.

The researchers believe that altering this process during periods when the building blocks for the brain are being laid down may be particularly important in explaining how genetic risk factors for autism get expressed.

Dr Lombardo adds: "Our discovery here meshes nicely with other recent findings that highlight the prenatal period around 15 weeks gestation as a key period when important genetic risk mechanisms for autism are working together to be expressed in the developing brain."

Professor Baron-Cohen said: "These results should not be taken as a reason to jump to steroid hormone blockers as a treatment as this could have unwanted side effects and may have little to no effect in changing the potentially permanent effects that fetal steroid hormones exert during the early foundational stages of brain development."

He cautioned further: "Nor should these results be taken as a promising prenatal screening test. There is considerable overlap between the groups and our findings showed differences found at an average group level, rather than at the level of accurately predicting diagnosis for individuals."

"The value of the new results lies in identifying key biological mechanisms during fetal development that could play important roles in atypical brain development in autism."

Autism: Diagnosis and Treatment

In the US April is National Autism Awareness Month.

The Child Development Clinic at Children's Hospital of Richmond at VCU (CHoR) provides comprehensive assessment for pediatric patients with developmental delays or disabilities, including those with autism spectrum disorders.

The medical, psychological, social work and educational testing offered by the clinic leads to a diagnosis and recommendations to help patients and their health care providers with care planning, referrals, follow-up care coordination and treatments.

Pasquale Accardo

We sat down with Pasquale Accardo, M.D., professor and chief of the Division of Developmental Pediatrics at CHoR, to learn more about autism, including symptoms, diagnosis and treatment.

What is autism?

Autism is a neurodevelopmental disorder, this means that it is a chronic brain problem, a difficulty that the brain has with processing certain kinds of information.

In the case of autism, typically the greatest difficulty is dealing with social interaction.

What are the common signs and symptoms of autism?

Common signs of autism vary with age:

• Young children often first present with language issues.
• Preschool and school-age children often exhibit attention deficit hyperactivity disorder (ADHD) symptoms and other challenging behaviours.
• Older children have significant socialization problems, repetitive and obsessive compulsive behaviours.

Symptoms of autism do change with time; certain delays are more common in younger children whereas socialization and processing problems are more common in older children and adults.

How is autism diagnosed?

Autism is diagnosed using a variety of approaches:

• A clinical history and examination may be sufficient.
• Formal testing can include a variety of questionnaires, including the Gilliam Autism Rating Scale, now in its 3rd edition (GARS-3) and the Childhood Autism Rating Scale, now in its 2nd edition (CARS-2) administered to the parents and teachers.
• Autism Diagnostic Observation Schedule (ADOS) testing is considered the gold standard.

How is autism treated?

Autism is best treated with a variety of Early Intensive Behavioural Interventions (EIBI); speech language therapy and occupational therapy can also be used.

Applied Behaviour Analysis (ABA) is considered the standard for behavioral intervention, but most other effective behavioral programs are variants on ABA.

Autism: Parents advised to get a dog

Many families face the decision of whether to get a dog.

For families of children with autism, the decision can be even more challenging.

Now, a University of Missouri researcher has studied dog ownership decisions in families of children with autism and found, regardless of whether they owned dogs, the parents reported the benefits of dog ownership included companionship, stress relief and opportunities for their children to learn responsibility.

"Children with autism spectrum disorders often struggle with interacting with others, which can make it difficult for them to form friendships," said Gretchen Carlisle, a research fellow at the Research Center for Human-Animal Interaction (ReCHAI) in the MU College of Veterinary Medicine.

"Children with autism may especially benefit from interacting with dogs, which can provide unconditional, nonjudgmental love and companionship to the children."

Carlisle interviewed 70 parents of children with autism. Nearly two-thirds of the parents in the study owned dogs, and of those parents, 94 percent reported their children with autism were bonded to their dogs.

Even in families without dogs, 70 percent of parents said their children with autism liked dogs.

Many dog-owning parents said they specifically chose to get dogs because of the perceived benefits to their children with autism, Carlisle said.

"Dogs can help children with autism by acting as a social lubricant," Carlisle said. "For example, children with autism may find it difficult to interact with other neighbourhood children."

"If the children with autism invite their peers to play with their dogs, then the dogs can serve as bridges that help the children with autism communicate with their peers."

Parents of children with autism should consider their children's sensitivities carefully when choosing a dog in order to ensure a good match between pet and child, Carlisle said.

"Bringing a dog into any family is a big step, but for families of children with autism, getting a dog should be a decision that's taken very seriously," Carlisle said.

"If a child with autism is sensitive to loud noises, choosing a dog that is likely to bark will not provide the best match for the child and the family."

"If the child has touch sensitivities, perhaps a dog with a softer coat, such as a poodle, would be better than a dog with a wiry or rough coat, such as a terrier."

Carlisle recommends parents involve their children with autism when choosing a dog.

"Many children with autism know the qualities they want in a dog," Carlisle said. "If parents could involve their kids in choosing dogs for their families, it may be more likely the children will have positive experiences with the animals when they are brought home."

Although her study only addressed dog ownership among families affected by autism, Carlisle said dogs might not be the best pet for every child with autism.

"If you know one child with autism, you know one child with autism," Carlisle said. "Dogs may be best for some families, although other pets such as cats, horses or rabbits might be better suited to other children with autism and their particular sensitivities and interests."

"This research adds scientific credibility to the benefits of human-animal interaction," said Rebecca Johnson, a professor at the MU College of Veterinary Medicine, director of ReCHAI, and the Millsap Professor of Gerontological Nursing in the MU Sinclair School of Nursing.

"This research helps us understand the role of companion animals in improving the lives of children with autism and helps health professionals learn how to best guide families in choosing pets for their families."

The study, "Pet Dog Ownership Decisions for Parents of Children With Autism Spectrum Disorder," was published in the Journal of Pediatric Nursing earlier this year.

Strategies for teaching common core to teens with autism show promise

Credit: High school classroom in Newark, Delaware, public domain image, courtesy of Wikimedia

Scientists at UNC's Frank Porter Graham Child Development Institute (FPG) report that high school students with autism can learn under Common Core State Standards (CCSS), boosting their prospects for college and employment.

Newly published recommendations from FPG's team also provide strategies for educating adolescents with autism under a CCSS curriculum.

Veronica P. Fleury

"The number of students with autism who enter high school settings continues to grow," said Veronica P. Fleury, lead author and postdoctoral research associate with FPG's Center on Secondary Education for Students with Autism Spectrum Disorders (CSESA).

"Many educators may find that they're not prepared to adapt their instruction to meet both state standards and the diverse needs of these students."

In 2010, the National Governors Association Center for Best Practices and the Council of Chief State School Officers released the CCSS for English and mathematics in an effort to better prepare students for college and careers.

According to Fleury, the greater demand for a technologically advanced workforce also makes academic skills now even more essential for high school graduates.

"But the college enrollment of people with autism is among the lowest for all categories of disabilities," Fleury said.

"In addition, less than 40% of the population with autism is employed, and most of those with jobs only work part-time, without benefits."

However, she said that academic performance in high school plays an important role in opportunities for a college education and employment.

Yet, while the CCSS outlines expectations of what educators should teach, it provides no guidance on how to teach these skills to students with or without autism.

Fleury believes the most effective high school instruction requires understanding the complex profile of students with ASD, who possess both strengths and weaknesses.

People with autism have some social deficits and may process language at a slower rate, she said, while many also have enhanced visual processing.

Some may have difficulty learning to make calculations, but others are mathematically gifted.

"It's extremely hard to draw general conclusions about academic performance for these students," Fleury said. "But adolescents with autism often do have difficulties comprehending texts, and many find writing a burdensome task."

Fluery added that work in STEM fields (science, technology, engineering, and math) are replacing manufacturing jobs and may provide viable opportunities for many people with ASD.

She said people with autism often gravitate to these fields in college, highlighting the need to equip them as high school students with skills that will enable them to compete and achieve.

"While the very structure of high school poses challenges for students with autism, being able to anticipate and understand activities, schedules, and expectations can improve their ability to respond to classroom demands," she said. "Establishing routines and creating written schedules also helps."

In a new article in Remedial and Special Education, Fleury and her co-authors recommended several strategies to educate students with ASD effectively, including exposing them to assignments before presenting the work in class.

The researchers also noted a variety of techniques for delivering the highly explicit instruction that teenagers with autism require, such as teaching mnemonic devices for remembering steps in a task.

"High school students with ASD also need ample opportunities to practice skills across settings throughout the school day," she said. "And teaching them to monitor their own behavior can help them to use their skills in a variety of settings."

Fleury added that because there is a strong link between social and academic skills, new research should focus on developing interventions for students with autism that can address both areas of need together.

"We know that when students with autism receive appropriate instruction and support, many of them are capable of learning academic content that is aligned with state standards, AND better academic performance often leads to a more successful outcome after high school." she said.

Autism: Low doses of antianxiety drugs may rebalance the autistic brain

New research in mice suggests that autism is characterized by reduced activity of inhibitory neurons and increased activity of excitatory neurons in the brain, but balance may be restored with low doses of a well-known class of drugs currently used in much higher doses to treat anxiety and epileptic seizures.

The findings, which are reported in the March 19th issue of the Cell Press journal Neuron, point to a new therapeutic approach to managing autism.

William Catterall

"These are very exciting results because they suggest that existing drugs, called benzodiazepines, might be useful in treatment of the core deficits in autism," says senior author Dr. William Catterall of the University of Washington, in Seattle.

In addition to finding that mice with autistic characteristics had an imbalance between the inhibitory and excitatory neurons in their brains, Dr. Catterall and his team found that reducing the effectiveness of inhibitory neurons in normal mice also induced some autism-related deficits in social behaviour.

Classical benzodiazepine drugs had the opposite effect, increasing the activity of inhibitory neurons and diminishing autistic behaviours.

"Our results provide strong evidence that increasing inhibitory neurotransmission is an effective approach to improvement of social interactions, repetitive behaviors, and cognitive deficits in a well-established animal model of autism, having some similar behavioral features as human autism," says Dr. Catterall.

Therapeutic approaches to treat autistic traits in animal studies or in clinical trials have primarily focused on reducing the activity of excitatory neurons, with only modest success to date.

The results reported by Dr. Catterall and his colleagues suggest that augmenting the activity of opposing, inhibitory neurons could be an alternative strategy.

Clinical trials of classical benzodiazepines and next-generation drugs that have a similar mechanism of action are now needed to determine whether the researchers' findings in mice are relevant to humans.

Astra-Zeneca and the National Institutes of Health (NIH) have initiated one such trial.

More information: Neuron, Han et al.: "Enhancement of Inhibitory Neurotransmission by GABAA Receptors Having 2,3-Subunits Ameliorates Behavioural Deficits in a Mouse Model of Autism." dx.doi.org/10.1016/j.neuron.2014.01.016

Autism: Superior visual thinking key to independence for ASD high schoolers

Researchers at UNC's Frank Porter Graham Child Development Institute (FPG) and UNC's School of Education report that teaching independence to adolescents with autism can provide a crucial boost to their chances for success after high school.

"We explored many factors that contribute to the poor outcomes people with autism often experience," said Kara Hume, co-principal investigator of FPG's Center on Secondary Education for Students with Autism Spectrum Disorders (CSESA).

"It's clear that teaching independence to students with autism should be a central focus of their activities in high school."

Kara Hume

According to Hume, independence is the biggest indicator of which students with autism spectrum disorder (ASD) are likely to live on their own, have a job, and participate in their communities after high school.

"However, adolescents with ASD have trouble observing their peers and picking up on skills important for developing independence," she said.

Hume also said students with ASD experience difficulties with communication that inhibit their ability to ask questions and express preferences, and many have trouble dealing with new situations.

This resistance to change can create problems when teachers and caregivers try to reduce their roles.

"When an adolescent with ASD has a pen that runs out of ink, that student may be more likely to wait for prompting from the teacher before asking for a new pen or just finding a new one," she said.

Hume added that it isn't easy to change this default setting from reliance on others to independent action.

Although adolescence is usually a time of increasing autonomy, research shows that the independence of young adults with ASD begins to plateau and then decline.

According to Hume, though, other scientists have demonstrated that many high schoolers with ASD also possess unique skills that teachers and caregivers can emphasize in order to teach independence.

"Brain imaging studies and research on visual tasks show that many people with autism have enhanced mental imagery and superior visual thinking, compared to typically developing people," Hume said.

She added that people with ASD also describe their own reasoning as a series of images.

"For high schoolers with autism, the old adage really is true," she said. "A picture really is worth a thousand words."

Last month, an FPG team released a new report and Fact Sheet for the National Professional Development Center on Autism Spectrum Disorders (NPDC), which screened 29,000 articles to determine the most reliable evidence-based interventions for children and youth with ASD.

Hume served on that team, helping to determine 12 evidence-based practices for high-school-aged students, and some of these interventions have a strong visual emphasis.

"Visual schedules, for instance, allow students with ASD to act independently, because they don't involve verbal prompting from teachers," Hume said.

"Visual information that explains what to do also can be useful in home, school, and employment settings, because it eliminates the need for continual monitoring and support."

Hume also said that video modeling, which the NPDC's report showed to be effective with other age groups, might also prove useful for high school students with ASD.

Prompting from teachers can be edited out over time as students become accustomed to behaving independently.

The new issue of Remedial and Special Education published recommendations from Hume and colleagues for promoting independence in adolescents with autism.

She and her co-authors also noted that new technology has the potential to capitalize on the visual strengths of people with ASD.

"IPads and iPhones are everywhere for typically developing teens," Hume said.

"The social acceptability of cell phone or tablet interventions for students with autism could lessen the stigma they face—and contribute to transformative outcomes after high school."

More information: Remedial and Special Education journal rse.sagepub.com/content/35/2/102.full.pdf+html

New guidelines employ a team approach to autism diagnosis and care

Fred Volkmar

Improving diagnosis and treatment for individuals with autism has been the focus of a growing body of research. 

New information from these studies led the American Academy of Child and Adolescent Psychiatry (AACAP) to revise key parameters for evaluating and treating autism. 

Researchers led by Yale Child Study Center director Dr. Fred Volkmar have published the new practice parameters in the Feb. issue of the Journal of the American Academy of Child and Adolescent Psychiatry.

"Early diagnosis of children with autism spectrum disorders means treatments will be introduced that lead to more positive outcomes for children," said Volkmar the Irving B. Harris Professor of Psychiatry, Pediatrics, and Psychology at the Yale School of Medicine.

According to the parameters, clinicians should routinely look for symptoms of autism spectrum disorder in young children undergoing developmental assessments, and in all psychiatric evaluations.

If significant symptoms are detected, clinicians should then coordinate a careful medical, psychological, and communication evaluation.

These evaluations should differentiate between autism and a variety of developmental and other disorders, as well as intellectual and behavioral disabilities.

"Our goal was advocacy for individuals with autism and their families, and to ensure that services are coordinated across clinical care," said Volkmar.

"Our field is changing rapidly, and these parameters are meant to promote effective care and move professional medical methods closer to current practices."

Volkmar and his co-authors reviewed abstracts from 9,481 research articles on autism that were published between 1991 and 2013.

They then fully studied 186 of those articles based on their quality and ability to be applied more generally.

"Treatment should involve a team approach," said Volkmar, who notes that under these treatment parameters, psychiatrists will closely coordinate diagnosis and treatment with teachers, behavioural psychologists, and speech and language pathologists, and look for commonly occurring conditions.

A key addition to the new parameters is a focus on how clinicians should address the use of non-traditional therapies, like chelation and secretin.

Clinicians are urged to ask families if they are using alternative/complementary treatments and to discuss the therapies' risks and potential benefits.

Volkmar estimates that about 90% of parents of children with autism use some kind of alternative or complementary therapies.

"It is important to encourage a discussion with parents about the potential harms of some of these therapies, as well as to educate them about evidence that supports what they're doing."

More information: Journal of the American Academy of Child & Adolescent Psychiatry: www.jaacap.com/article/S0890-8567(13)00819-8/fulltext

Autism: Birth hormone controls the expression of the syndrome in animals

Researchers found that a drug affecting chloride levels improves autistic-like behaviour in offspring of mouse models of autism. 

The drug restores the so-called GABA switch in the neurons of fetal mice when given to the mother one day before delivery. 

Credit: D.C. Ferrari

The scientific community agrees that autism has its origins in early life—foetal and/or postnatal.

The team led by Yehezkel Ben-Ari, Inserm Emeritus Research Director at the Mediterranean Institute of Neurobiology (INMED), has made a breakthrough in the understanding of the disorder.

In an article published in Science, the researchers demonstrate that chloride levels are elevated in the neurons of mice used in an animal model of autism, and remain at abnormal levels from birth.

These results corroborate the success obtained with the diuretic treatment tested on autistic children by the researchers and clinicians in 2012, and suggest that administration of diuretics to mice before birth corrects the deficits in the offspring.

They also show that oxytocin, the birth hormone, brings about a decrease in chloride level during birth, which controls the expression of the autistic syndrome.

This work is due to appear in the 7 February 2014 issue of Science.

Neurons contain high levels of chloride throughout the entire embryonic phase. As a result, GABA, the main chemical messenger of the brain, excites the neurons during this phase instead of inhibiting them, in order to facilitate construction of the brain.

Subsequently, a natural reduction in chloride levels allows GABA to exercise its inhibitory role and regulate the activity of the adolescent/adult brain.

In many brain disorders (childhood epilepsy, cranial trauma, etc.), studies have shown abnormally high chloride levels.

Having made various observations, Dr Lemonnier's team (Brest), and Yehezkel Ben-Ari's team at Inserm carried out a clinical trial in 2012, based on the hypothesis of high chloride levels in the neurons of patients with autism.

The researchers showed that administration of a diuretic to children with autism (which reduces neuronal chloride levels) has beneficial effects.

The results of the trial supported this hypothesis, but because high neuronal chloride levels could not be demonstrated in children with autism, it was not possible to prove the mechanism proposed or justify the treatment.

In the present study, the researchers therefore used two animal models of autism, a genetic model, Fragile X syndrome, which is the genetic mutation most frequently associated with autism, and another, generated by injecting the pregnant mice with sodium valproate, a product known to generate abnormalities in children, including autistic spectrum disorder.

A high level of chloride in the brain
For the first time, the researchers recorded the activity of neurons at the embryonic stage and immediately after birth to observe modifications in chloride levels.

These observations showed that neuronal chloride levels are abnormally high in both young and adult animals used in the autism model.

GABA strongly excites neurons, and the researchers recorded aberrant electrical activities in the brain, which persist in adult animals.

The fall in chloride level, a particularly impressive phenomenon seen at birth in control animals, is absent in both of these animal models, and the neurons have the same chloride level before and after birth.

These high levels are due to reduced activity of a chloride transporter, thus preventing transport of chloride out of the neuron. As a result, a major feature of neurons during birth is abolished in animal models of autism.

Clinical trials of the drug bumetanide administered in young children with autistic symptoms are showing progress. 

Credit: D.C. Ferrari

"Chloride levels during delivery are determinants of the occurrence of autism spectrum disorder," explains Yehezkel Ben-Ari, an Emeritus Research Director at Inserm.

Beneficial effects of the diuretic on brain activity.
The researchers administered a diuretic treatment to the mother (in both animal models) for 24 hours shortly before delivery to see if this would restore brain inhibition in the offspring.

They showed that the drop in chloride level was re-established in the neurons several weeks after a single treatment during birth.

According to the research team, antenatal treatment restored brain activity to approximately normal levels, and corrected the "autistic" behaviour in the animals once they became adults.

"These results thus validate the working hypothesis that led us to the treatment we developed in 2012," states the principal author of the study.

Oxytocin, the birth hormone, naturally reduces chloride levels
The role of oxytocin in reducing neuronal chloride was also studied. The researchers had previously shown in 2006 that this hormone, which triggers labour, also has many beneficial actions on the brains of newborns, including protective effects in the event of complications during delivery, and even analgesic properties.

Oxytocin acts like the diuretic, reducing the intracellular chloride levels.

By administering the drug bumetanide to pregnant mice with models of autism, the researchers were able to reduce chloride levels in the brains of their offspring to their appropriate levels -- and in turn, to restore the GABA switch mechanism required for healthy brain development. 

Credit: D.C. Ferrari

In the present study, the team tested the long-term effects of blocking the actions of the hormone before birth.

A drug that blocks the signals generated by oxytocin was injected into pregnant mice.

The researchers evaluated the effects of this blockage on the offspring, and showed that it reproduced the entire autism-like syndrome in them, both with respect to the electrical and behavioural aspects (identical to the two animal models of autism).

As a result, the hormone's natural actions, just like those of the diuretic, are crucial to this delicate phase, and may control the pathogenesis of autism via the cellular chloride levels.

"These data validate our treatment strategy, and suggest that oxytocin, by acting on the chloride levels during delivery modulates/controls the expression of autism spectrum disorder," states Yehezkel Ben-Ari.

Taken together, these observations suggest that earliest possible treatment is essential for maximum possible prevention of the disorder.

This work raises the importance of carrying out early epidemiological studies in order to better understand the pathogenesis of the disorder, especially through analysing data on deliveries where a drop in chloride has occurred.

Indeed, complicated deliveries with episodes of prolonged lack of oxygen, for example, or complications during pregnancy, such as viral infections, are often suggested as risk factors.

Finally, given the role of oxytocin in triggering labour, "although it is true that epidemiological data suggesting that scheduled caesarean deliveries may have increased the incidence of autism are controversial, it nonetheless remains that these studies should be followed up and extended to confirm or refute this relationship, which is still possible," insists Yehezkel Ben-Ari, who concludes,

"To treat this type of disorder, it is necessary to understand how the brain develops and how genetic mutations and environmental insults modulate brain activity in utero."

More information: : "Oxytocin-Mediated GABA Inhibition During Delivery Attenuates Autism Pathogenesis in Rodent Offspring," by R. Tyzio et al. Science, 2014. DOI: 10.1126/science.1247190