Autism

A recent report from Autistica estimates that nearly a quarter (24%) of children with autism are non-verbal or minimally verbal — problems that can persist into adulthood.

A review of over 200 published papers and more than 60 different intervention studies has now concluded that:

  • Motor behaviors play a key role in language learning.
  • Children with autism show specific motor impairments, and less "mirroring" brain activity.
  • There is very little evidence that sign language training helps.
  • Picture exchange training can help.
  • Play-based approaches which employ explicit teaching strategies and are developmentally based are particularly successful.
  • New studies involving a focus on motor skills show promising preliminary results.

The paper can be freely downloaded at http://www.frontiersin.org/Integrative_Neuroscience/10.3389/fnint.2013.00030/abstract

http://www.eurekalert.org/pub_releases/2013-04/f-nhf042213.php

[3418] McCleery JP, Elliott NA, Sampanis DS, Stefanidou CA. Motor development and motor resonance difficulties in autism: relevance to early intervention for language and communication skills. Frontiers in Integrative Neuroscience [Internet]. 2013 ;7. Available from: http://www.frontiersin.org/Integrative_Neuroscience/10.3389/fnint.2013.00030/abstract

A humanoid robot has been designed, and shows promise, for teaching joint attention to children with ASD. Robots are particularly appealing to children, and even more so to those with ASD.

http://www.futurity.org/health-medicine/interactive-robot-trains-kids-with-autism/

[3351] Bekele ET, Lahiri U, Swanson AR, Crittendon JA, Warren ZE, Sarkar N. A Step Towards Developing Adaptive Robot-Mediated Intervention Architecture (ARIA) for Children With Autism. IEEE Transactions on Neural Systems and Rehabilitation Engineering. 2013 ;21(2):289 - 299.

We say so blithely that children learn by copying, but a recent study comparing autistic children and normally-developing ones shows there’s more to this than is obvious.

The study, involving 31 children with ASD, 30 typically developing children matched for language skills, and 30 typically developing age-matched children, had the children watch an adult model how to perform a simple action. The demonstration included two vital actions and one superfluous action. The child was then asked to undertake the same task (without mentioning any need to copy all of the actions of the adult exactly as they had seen them).

Almost all children (97%) successfully managed the task, but while typical children copied 43-57% of the unnecessary actions, autistic children copied only 22%. This despite the fact that, when shown the demonstration again and asked to judge whether each action was “sensible” or “silly,” the children (and especially typical children) had no trouble recognizing the unnecessary actions as silly.

In other words, it’s not about reasoning ability, it’s about social motivation. Typical children want to please adults and ‘fit in’, so they copy even the silly actions. Autistic children care less about this.

The findings point to the social nature of copying behavior — it’s not simply about learning.

http://www.futurity.org/society-culture/kids-with-autism-mimic-%e2%80%98more-efficiently%e2%80%99/

[3360] Marsh L, Pearson A, Ropar D, Hamilton A. Children with autism do not overimitate. Current Biology [Internet]. 2013 ;23(7):R266 - R268. Available from: http://www.cell.com/current-biology/abstract/S0960-9822(13)00207-8

A study involving 97 infants, of whom 56 were at high risk of an autism spectrum disorder, has found that the high-risk infants later found to have ASD (only 16 of the 56) were slower to orient or shift their gaze (by approximately 50 milliseconds) than both high-risk-negative and low-risk infants. Moreover, visual orienting in low-risk infants was uniquely associated with a specific neural circuit (the splenium of the corpus callosum), but was not in those later classified with ASD.

In other words, atypical visual orienting, seen early in ASD, is associated with a deficit in a specific neural circuit in the brain.

http://www.futurity.org/health-medicine/infants%e2%80%99-slow-gaze-may-signal-autism-later/

Elison, J.T. et al. 2013. White Matter Microstructure and Atypical Visual Orienting in 7-Month-Olds at Risk for Autism. Am J Psychiatry 2013;:. 10.1176/appi.ajp.2012.12091150

A review of 25 major studies investigating the value of sensory integration therapy (SIT) for autistic children has concluded that this most popular of therapies has no scientific support.

Only three of the 25 studies found benefits from SIT, and these three all had serious methodological flaws. Eight of the studies found mixed results, while 14 studies reported no benefits. Many of the reviewed studies had serious methodological flaws.

It has been suggested that SIT may even be harmful, in that it may lead to an increase in undesirable behavior. Regardless, by taking up time that could otherwise be spent on effective therapies, the use of SIT is not recommended.

The only scientifically valid treatment and intervention for individuals on the autism spectrum is said to be applied behavior analysis, in which, unfortunately, few are trained. With applied behavior analysis, the therapist teaches children age-appropriate skills and offers systematic, repetitious positive reinforcement for desired behaviors.

The importance of early diagnosis for autism spectrum disorder has been highlighted by a recent study demonstrating the value of an educational program for toddlers with ASD.

The study involved 48 toddlers (18-30 months) diagnosed with autism and age-matched normally developing controls. Those with ASD were randomly assigned to participate in a two-year program called the Early Start Denver Model, or a standard community program.

The ESDM program involved two-hour sessions by trained therapists twice a day, five days every week. Parent training also enabled ESDM strategies to be used during daily activities. The program emphasizes interpersonal exchange, social attention, and shared engagement. It also includes training in face recognition, using individualized booklets of color photos of the faces of four familiar people.

The community program involved evaluation and advice, annual follow-up sessions, programs at Birth-to-Three centers and individual speech-language therapy, occupational therapy, and/or applied behavior analysis treatments.

All of those in the ESDM program were still participating at the end of the two years, compared to 88% of the community program participants.

At the end of the program, children were assessed on various cognitive and behavioral measures, as well as brain activity.

Compared with children who participated in the community program, children who received ESDM showed significant improvements in IQ, language, adaptive behavior, and autism diagnosis. Average verbal IQ for the ESDM group was 95 compared to an average 75 for the community group, and 93 vs 80 for nonverbal IQ. These are dramatically large differences, although it must be noted that individual variability was high.

Moreover, for the ESDM group, brain activity in response to faces was similar to that of normally-developing children, while the community group showed the pattern typical of autism (greater activity in response to objects compared to faces). This was associated with improvements in social behavior.

Again, there were significant individual differences. Specifically, 73% of the ESDM group, 53% of the control group, and 29% of the community group, showed a pattern of faster response to faces. (Bear in mind, re the control group, that these children are all still quite young.) It should also be borne in mind that it was difficult to get usable EEG data from many of the children with ASD — these results come from only 60% of the children with ASD.

Nevertheless, the findings are encouraging for parents looking to help their children.

It should also be noted that, although obviously earlier is better, the findings don’t rule out benefits for older children or even adults. Relatively brief targeted training in face recognition has been shown to affect brain activity patterns in adults with ASD.

I’ve reported before on evidence that young children do better on motor tasks when they talk to themselves out loud, and learn better when they explain things to themselves or (even better) their mother. A new study extends those findings to children with autism.

In the study, 15 high-functioning adults with Autism Spectrum Disorder and 16 controls (age and IQ matched) completed the Tower of London task, used to measure planning ability. This task requires you to move five colored disks on three pegs from one arrangement to another in as few moves as possible. Participants did the task under normal conditions as well as under an 'articulatory suppression' condition whereby they had to repeat out loud a certain word ('Tuesday' or 'Thursday') throughout the task, preventing them from using inner speech.

Those with ASD did significantly worse than the controls in the normal condition (although the difference wasn’t large), but they did significantly better in the suppression condition — not because their performance changed, but because the controls were significantly badly affected by having their inner speech disrupted.

On an individual basis, nearly 90% of the control participants did significantly worse on the Tower of London task when inner speech was prevented, compared to only a third of those with ASD. Moreover, the size of the effect among those with ASD was correlated with measures of communication ability (but not with verbal IQ).

A previous experiment had confirmed that these neurotypical and autistic adults both showed similar patterns of serial recall for labeled pictures. Half the pictures had phonologically similar labels (bat, cat, hat, mat, map, rat, tap, cap), and the other nine had phonologically dissimilar labels (drum, shoe, fork, bell, leaf, bird, lock, fox). Both groups were significantly affected by phonological similarity, and both groups were significantly affected when inner speech was prevented.

In other words, this group of ASD adults were perfectly capable of inner speech, but they were much less inclined to use it when planning their actions.

It seems likely that, rather than using inner speech, they were relying on their visuospatial abilities, which tend to be higher in individuals with ASD. Supporting this, visuospatial ability (measured by the block design subtest of the WAIS) was highly correlated with performance on the Tower of London test. Which may not seem surprising, but the association was minimal in control participants.

Complex planning is said to be a problem for many with ASD. It’s also suggested that the relative lack of inner speech use might contribute to some of the repetitive behaviors common in people with autism.

It may be that strategies targeted at encouraging inner speech may help those with ASD develop such skills. Such strategies include encouraging children to describe their actions out loud, and providing “parallel talk”, whereby an observer plays alongside the child while verbalizing their actions.

It is also suggested that children with ASD could benefit from verbal learning of their daily schedule at school rather than using visual timetables as is currently a common approach. This could occur in stages, moving from pictures to symbols, symbols with words, before finally being restricted to words only.

ASD is estimated to occur in 1% of the population, but perhaps this problem could be considered more widely. Rather than seeing this as an issue limited to those with ASD, we should see this as a pointer to the usefulness of inner speech, and its correlation with communication skills. As one of the researchers said: "These results show that inner speech has its roots in interpersonal communication with others early in life, and it demonstrates that people who are poor at communicating with others will generally be poor at communicating with themselves.”

One final comment: a distinction has been made between “dialogic” and “monologic” inner speech, where dialogic speech refers to a kind of conversation between different perspectives on reality, and monologic speech is simply a commentary to oneself about the state of affairs. It may be that it is specifically dialogic inner speech that is so helpful for problem-solving. It has been suggested that ASD is marked by a reduction in this kind of inner speech only, and the present researchers suggest further that it is this form of speech that may have inherently social origins and require training or experience in communicating with others.

The corollary to this is that it is only in those situations where dialogic inner speech is useful in achieving a task, that such differences between individuals will matter.

Clearly there is a need for much more research in this area, but it certainly provides food for thought.

Bilingual parents of children with autism spectrum disorder often decide to speak only one language around their child because of advice from child development professionals who believe that exposure to two languages might further limit the child’s communication skills. Two recent studies challenge that assumption.

One study tested the vocabulary size of 14 bilingual (English-Mandarin/Cantonese) and 14 English-monolingual young children with ASD (aged 3-6). Bilingual children had a larger total vocabulary than monolingual children. When translation equivalents (two words in each language with the same meaning) were counted only once, the vocabularies of both bilingual and monolingual children were not significantly different. Both groups had equivalent scores on all but one measure of language and vocabulary, including English production vocabulary, conceptual production vocabulary, and vocabulary comprehension.

The second Canadian study found similar results in a slightly larger group of children (45 bilingual and 30 monolingual children with an average age of around 5). Languages covered were diverse: French, English, Chinese, Farsi, Hebrew, Italian, Romanian, Spanish and Tamil. Bilingual children were divided into those who were exposed to both languages from infancy, and those who were exposed later (the cut-off was 12 months, but in general changes in the language environment occurred much later: on average, children in the former group were bilingually-exposed for the first 25 months; children in the latter group were monolingually-exposed for the first 31 months). Eleven children were trilingual. In order not to introduce sampler bias, non-verbal children were not excluded — seven participants spoke fewer than 10 words, of whom two were nonverbal.

There were no significant differences between the three groups at a language level, although monolingual and bilingual children exposed from infancy consistently scored higher than bilingual children exposed from a later age. Also, children exposed to two or more languages from infancy scored significantly higher than both groups on social interaction, and those exposed later were worst of the three groups. These differences probably reflect various social variables underlying the different language experiences.

The main reason for the belief that autistic children are better not ‘burdened’ with an additional language is because of their language difficulties. These studies are not saying that a child with ASD raised in two languages will be equally fluent with both. In the second study, second language vocabularies were much smaller than their dominant language vocabularies. But that’s not the point. Whether or not there is any general cognitive advantage in bilingualism for this group, as there is for normally-developing children, remains to be determined. But there is a clear message that parents of ASD children can take on board: if your family is bilingual, relax and enjoy interacting with your ASD child in your language of choice.

Increased awareness and changes in diagnostic criteria can’t entirely explain the massive increase in autism — the U.S. Centers for Disease Control reported a 57% increase between 2002 and 2006. Another factor may involve environmental pollutants.

A Californian study involving 304 autism cases and 259 typically developing controls has found that living within 309 meters of a freeway at birth or during the third trimester was associated with a two-fold increase in autism risk. This association held after adjustment for gender, ethnicity, parental education, maternal age, or prenatal smoking. The researchers found no consistent pattern of association of autism with proximity to a major road.

The finding is consistent with other evidence that oxidative stress and inflammation are involved in the pathogenesis of autism. This is likely to be only one of many environmental factors that are involved.

Contrary to previous laboratory studies showing that children with autism often demonstrate outstanding visual search skills, new research indicates that in real-life situations, children with autism are unable to search effectively for objects. The study, involving 20 autistic children and 20 normally-developing children (aged 8-14), used a novel test room, with buttons on the floor that the children had to press to find a hidden target among multiple illuminated locations. Critically, 80% of these targets appeared on one side of the room.

Although autistics are generally believed to be more systematic, with greater sensitivity to regularities within a system, such behavior was not observed. Compared to other children, those with autism were slower to pick up on the regularities that would help them choose where to search. The slowness was not due to a lack of interest — all the children seemed to enjoy the game, and were keen to find the hidden targets.

The findings suggest that those with ASD have difficulties in applying the rules of probability to larger environments, particularly when they themselves are part of that environment.

[2055] Pellicano E, Smith AD, Cristino F, Hood BM, Briscoe J, Gilchrist ID. Children with autism are neither systematic nor optimal foragers. Proceedings of the National Academy of Sciences [Internet]. 2011 ;108(1):421 - 426. Available from: http://www.pnas.org/content/108/1/421.abstract

Last month I reported on a finding that toddlers with autism spectrum disorder showed a strong preference for looking at moving shapes rather than active people. This lower interest in people is supported by a new imaging study involving 62 children aged 4-17, of whom 25 were diagnosed with autistic spectrum disorder and 20 were siblings of children with ASD.

In the study, participants were shown point-light displays (videos created by placing lights on the major joints of a person and filming them moving in the dark). Those with ASD showed reduced activity in specific regions (right amygdala, ventromedial prefrontal cortex, right posterior superior temporal sulcus, left ventrolateral prefrontal cortex, and the fusiform gyri) when they were watching a point-light display of biological motion compared with a display of moving dots. These same regions have also been implicated in previous research with adults with ASD.

Moreover, the severity of social deficits correlated with degrees of activity in the right pSTS specifically. More surprisingly, other brain regions (left dorsolateral prefrontal cortex, right inferior temporal gyrus, and a different part of the fusiform gyri) showed reduced activity in both the siblings group and the ASD group compared to controls. The sibling group also showed signs of compensatory activity, with some regions (right posterior temporal sulcus and a different part of the ventromedial prefrontal cortex) working harder than normal.

The implications of this will be somewhat controversial, and more research will be needed to verify these findings.

Many genes have been implicated in autism; one of them is the CNTNAP2 gene. This gene (which is also implicated in specific language disorder) is most active during brain development in the frontal lobe. An imaging study involving 32 children, half of whom had autism, has revealed that regardless of their diagnosis, the children carrying the risk variant showed communication problems within and with the frontal lobe. The frontal lobe was over-connected to itself and poorly connected to the rest of the brain, particularly the back of the brain.

There were also differences in connectivity between the left and right sides of the brain — in those with the non-risk gene, communication pathways in the frontal lobe linked more strongly to the left side of the brain (which is more strongly involved in language), but in those with the risk variant, the communications pathways connected more broadly to both sides of the brain.

The findings could lead to earlier detection of autism, and new interventions to strengthen connections between the frontal lobe and left side of the brain. But it should be emphasized that the autistic spectrum disorders probably encompass a number of different genetic patterns associated with different variants of ASD.

It should also be emphasized that this gene variant, although it increases the risk of various neurodevelopmental disorders (such as specific language impairment, which has also been associated with this gene), is found among a third of the population. So the pattern of connectivity, although not ‘normal’ (i.e., the majority position), is not abnormal. It would be interesting to explore whether other, more subtle, cognitive differences correlate with this genetic difference.

Scott-Van Zeeland., A.A. et al. 2010. Altered Functional Connectivity in Frontal Lobe Circuits Is Associated with Variation in the Autism Risk Gene CNTNAP2. Science Translational Medicine, 2 (56), DOI: 10.1126/scitranslmed.3001344 http://stm.sciencemag.org/content/2/56/56ra80.abstract

No one is denying that boys are far more likely to be autistic than girls, but a new study has found that this perception of autism as a male disorder also means that girls are less likely to be diagnosed with autistic spectrum disorder (ASD) even when their symptoms are equally severe.

Another factor affecting diagnosis was maternal age — those diagnosed with ASD were likely to have older mothers. It’s suggested that this may be because older mothers are better at identifying their children's difficulties and have more confidence in bringing concerns to the clinic. This is supported by the finding that first-born children were less likely to be diagnosed with ASD, as were children of mothers with depression.

Ethnic origin, maternal class and mother's marital status did not significantly predict a child either having an ASD diagnosis or displaying severe autistic traits.

The findings were based on an analysis of data from a longitudinal UK cohort study, the Avon Longitudinal Study of Parents and Children (ALSPAC).

Russell, G., Steer, C. & Golding, J. 2010. Social and demographic factors that influence the diagnosis of autistic spectrum disorders. Social Psychiatry and Psychiatric Epidemiology. DOI 10.1007/s00127-010-0294-z.
Full text is available at http://springerlink.com/content/a67371l826m1xl76/fulltext.pdf

A study involving 110 toddlers (aged 14-42 months), of whom 37 were diagnosed with an autism spectrum disorder and 22 with a developmental delay, has compared their behavior when watching a 1-minute movie depicting moving geometric patterns (a standard screen saver) on 1 side of a video monitor and children in high action, such as dancing or doing yoga, on the other.

It was found that only one of the 51 typically-developing toddlers preferred the shapes, but 40% of the ASD toddlers did, as well as 9% of the developmentally delayed toddlers. Moreover, all those who spent over 69% of the time focusing on the moving shapes were those with ASD.

Additionally, those with ASD who preferred the geometric images also showed a particular pattern of saccades (eye movements) when viewing the images — a reduced number of saccades, demonstrated in a fixed stare. It’s suggested that a preference for moving geometric patterns combined with lengthy absorption in such images, might be an early identifier of autism. Such behavior should be taken as a signal to look for other warning signs, such as reduced enjoyment during back-and-forth games like peek-a-boo; an unusual tone of voice; failure to point at or bring objects to show; and failure to respond to their name.

[1891] Pierce K, Conant D, Hazin R, Stoner R, Desmond J. Preference for Geometric Patterns Early in Life As a Risk Factor for Autism. Arch Gen Psychiatry [Internet]. 2010 :archgenpsychiatry.2010.113 - archgenpsychiatry.2010.113. Available from: http://archpsyc.ama-assn.org/cgi/content/abstract/archgenpsychiatry.2010.113v1

Children with autism often focus intently on a single activity or feature of their environment. A study involving 17 autistic children (6-16 years) and 17 controls has compared brain activity as they watched a silent video of their choice while tones and vibrations were presented, separately and simultaneously.

A simple stimulus takes about 20 milliseconds to arrive in the brain. When information from multiple senses registers at the same time, integration takes about 100 to 200 milliseconds in normally developing children. But those with autism took an average of 310 milliseconds to integrate the noise and vibration when they occurred together. The children with autism also showed weaker signal strength, signified by lower amplitude brainwaves.

The findings are consistent with theories that automatic sensory integration is impaired in autism, and may help explain autism’s characteristic sensitivity to excessive sensory stimulation.

A new automated vocal analysis technology can discriminate pre-verbal vocalizations of very young children with autism with 86% accuracy. The LENA™ (Language Environment Analysis) system also differentiated typically developing children and children with autism from children with language delay. The processor fits into the pocket of specially designed children's clothing and records everything the child vocalizes. LENA could not only enable better early diagnosis of autism spectrum disorders, but also allow parents to continue and supplement language enrichment therapy at home and assess their own effectiveness for themselves.

A five-year study involving 48 diverse, 18- to 30-month-old children with autism and no other health problems has found a novel early intervention program to be effective for improving IQ, language ability, and social interaction. The Early Start Denver Model combines applied behavioral analysis (ABA) teaching methods with play-based routines that focused on building a relationship with the child. Half the children received two two-hour sessions five days a week from specialists (but in their own homes) plus five hours a week of parent-delivered therapy. The remaining children were referred to community-based programs. After two years, the IQs of the children in the intervention group had improved by an average of around 18 points, compared to a little more than four points in the comparison group. The intervention group also had a nearly 18-point improvement in receptive language (listening and understanding) compared to around10 points in the comparison group. Seven of the children in the intervention group received an improved diagnosis from autism to the milder condition known as 'pervasive developmental disorder not otherwise specified' (PDD-NOS), compared to only one child in the community-based therapy group.

Previous research has found that individual neurons can become tuned to specific concepts or categories. We can have "cat" neurons, and "car" neurons, and even an “Angelina Jolie” neuron. A new monkey study, however, reveals that although some neurons were more attuned to car images and others to animal images, many neurons were active in both categories. More importantly, these "multitasking" neurons were in fact the best at making correct identifications when the monkey alternated between two category problems. The work could lead to a better understanding of disorders such as autism and schizophrenia in which individuals become overwhelmed by individual stimuli.

Additional brief reports

Genes for autism and schizophrenia only active in developing brains

February 11, 2013

Genes linked to autism and schizophrenia are only switched on during the early stages of brain development, according to a study in mice.

It has been suspected for a long time that if the development of the cortex is disrupted by genetic abnormalities or environmental stress (such as prematurity) this would have long-lasting adverse effects on brain development and could lead to problems like ADHD or autism. This study defines genes that are important in mice at this critical period and this does indeed seem to include genes known to predispose to autism and schizophrenia.

http://medicalxpress.com/news/2013-02-genes-autism-schizophrenia-brains.html

Scientists investigate inherited causes of autism

February 4, 2013

Two new studies investigate the role recessive genes play in ASD. These genes can be passed on through generations, but their effects are seen only if an individual inherits two identical copies of the gene – one from each parent.

One study found that approximately 5% of autism cases could be linked to inherited, recessive mutations that completely disrupt gene function. A second study found that autism risk could also be attributed to inherited mutations that resulted in only a partial loss of gene function.

The number of different genetic mutations uncovered by the two studies supports the long-held theory that autism is a heterogeneous condition with many different genetic causes.

http://medicalxpress.com/news/2013-02-scientists-inherited-autism.html

Gene target shows promise for autism

January 3, 2013

Mouse study found that chemically normalizing excessive levels of protein synthesis induced by a variant of the EIF4E gene, whose mutation is associated with autism, significantly reduced autistic-like behaviors. The mice were less likely to engage in repetitive behaviors, more likely to interact with other mice, and were successful in navigating mazes that differed from those they previously solved.

http://www.futurity.org/health-medicine/gene-target-shows-promise-for-autism/

Air pollution drives up autism risk

Exposure to traffic-related air pollution during pregnancy and the first year of life was associated with a more than two-fold risk of autism. Exposure to regional pollution was also associated with autism even if the mother did not live near a busy road.

http://www.futurity.org/health-medicine/air-pollution-drives-up-autism-risk/

note criticism of the study: http://www.forbes.com/sites/emilywillingham/2012/11/27/5-caveats-about-the-autism-and-air-pollution-study/

Autism risk test is 70% accurate

September 12, 2012

A new genetic test predicted a person’s risk of developing an autism spectrum disorder with over 70% accuracy. Participants were all of central European descent. The test uses 237 genetic markers (SNPs) in 146 genes and related cellular pathways.

http://www.futurity.org/health-medicine/autism-risk-test-is-70-percent-accurate/

Unreliable neural response in autistic adults

September 20, 2012

A small study shows that autistic adults have unreliable neural sensory responses to visual, auditory, and somatosensory, or touch, stimuli. This poor response reliability appears to be a fundamental neural characteristic of autism. Non-autistic individuals showed reliably consistent brain activity to sensory information, while autistic individuals showed marked trial-by-trial variability. It’s suggested that such unreliable activity might be what’s limiting the development of social and language abilities.

http://www.futurity.org/health-medicine/unreliable-neural-response-in-autistic-adults/

Electrical Activity in the Brain Can Distinguish Children With Autism

June 27, 2012

A large study found that patterns of electrical activity in the brain can distinguish children with autism from children with typical brains as early as age 2. In general, autistic children showed reduced connectivity.

http://blogs.edweek.org/edweek/speced/2012/06/electrical_activity_in_the_brain_can.html

Autism and schizophrenia may share root cause

July 3, 2012

The risk of an autism spectrum disorder may be higher among people whose parents or siblings have been diagnosed with schizophrenia or bipolar disorder.

The presence of schizophrenia in parents was associated with an almost three times increased risk for autism spectrum disorders in Swedish groups. Schizophrenia in a sibling also was associated with roughly two and a half times the risk for autism in the Swedish national group and a 12 times greater risk in a sample of Israeli military conscripts (perhaps because of individuals with earlier onset schizophrenia, “which has a higher sibling recurrence”).

Bipolar disorder showed a similar pattern of association but of a lesser magnitude, study results indicate.

http://www.futurity.org/health-medicine/autism-and-schizophrenia-may-share-root-cause/

The ‘autism epidemic’ and diagnostic substitution

Excellent article on the question of why there’s been such an increase in autism diagnoses. The researcher makes a strong case that it is because of changes in diagnosis rather than a true increase.

http://deevybee.blogspot.com/2012/06/autism-epidemic-and-diagnostic.html

Oxytocin improves brain function in children with autism

Preliminary results from an ongoing, large-scale study shows that oxytocin increased brain function in regions that are known to process social information in children and adolescents with autism spectrum disorders.

http://www.eurekalert.org/pub_releases/2012-05/yu-oib051812.php

Research shows how PCBs promote dendrite growth, may increase autism risk

New research shows that PCBs, or polychlorinated biphenyls, launch a cellular chain of events that leads to an overabundance of dendrites and disrupts normal patterns of neuronal connections in the brain. "Impaired neuronal connectivity is a common feature of a number of conditions, including autism spectrum disorders." It’s suggested that PCB exposure "may increase the likelihood of autism in children whose genetic makeup already compromises the processes by which neurons form connections."

http://www.eurekalert.org/pub_releases/2012-04/uoc--rsh042512.php

http://www.futurity.org/health-medicine/toxic-pcbs-scramble-brain-connections/

Full text available at http://ehp03.niehs.nih.gov/article/info%3Adoi%2F10.1289%2Fehp.1104833

Protein in overdrive links to autism

March 21, 2012

A mouse study suggests that early disruptions in serotonin signaling in the brain may contribute to autism spectrum disorder. It has long been known that many children with autism have elevated blood levels of serotonin (hyperserotonemia).

http://www.futurity.org/health-medicine/serotonin-in-overdrive-links-to-autism/

People with autism possess greater ability to process information, study suggests

A small study suggests that people with autism spectrum disorders have a greater than normal capacity for processing perceptual information even from rapid presentations and are better able to detect information defined as 'critical'.

http://www.eurekalert.org/pub_releases/2012-03/wt-pwa032212.php

Autism mutations, scattered across many genes, merge into common network of interactions

A large study looking at the genes of children with sporadic autism" (no family history) has found that many mutations related to modifying chromatin (the tightly coiled spools of DNA in the cell), changing the way DNA is packaged. They also found that new mutations were overwhelming paternal in origin (in a ratio of 4:1), that the new mutations occurred at a rate that correlated with the age of the father.

What is also very clear from this and other recent studies is that autism risk mutations are scattered across many genes. It’s suggested that although no single gene will account for more than 1% of autism cases, collectively all of these rare mutations will account for much of the genetic basis of the disease.

http://www.eurekalert.org/pub_releases/2012-04/uow-ams040212.php

Evolution's gift may also be at the root of a form of autism

May 10th, 2012

A study has identified the evolutionary changes that led the NOS1 gene to become active specifically in the parts of the developing human brain that form the adult centers for speech and language and decision-making. This pattern of NOS1 activity is controlled by a protein called FMRP and is missing in Fragile X syndrome. Fragile X syndrome, the leading inherited form of intellectual disability, is also the most common single-gene cause of autism.

http://medicalxpress.com/news/2012-05-evolution-gift-root-autism.html

Researchers discover new genes contributing to autism, links to psychiatric disorders

April 19th, 2012

A new approach to investigating hard-to-find chromosomal abnormalities has identified 33 genes associated with autism and related disorders, 22 for the first time. Several of these genes also appear to be altered in different ways in individuals with psychiatric disorders such as schizophrenia.

http://medicalxpress.com/news/2012-04-genes-contributing-autism-links-psychiatric.html

RNA discovery offers clue in autism puzzle

April 5, 2012

Scientists have discovered the first gene associated with autism that has genome-wide significance. Expression of MSNP1AS was increased 12-fold in the brains of people with autism. This gene controls expression of a protein called moesin, which influences brain development and immune response.

http://www.futurity.org/health-medicine/rna-discovery-offers-clue-in-autism-puzzle/

Study identifies gene expression abnormalities in autism

March 22nd, 2012

Following previous research showing a link between autism and excess brain cells in the prefrontal cortex, a study has showed that genetic mechanisms that normally regulate the number of cortical neurons are abnormal in such cases. This abnormality may not only result in too many neurons in some regions, but not enough in others.

Moreover, while the adolescent prefrontal cortex showed dysregulation in the pathways that govern cell number, cortical patterning and cell differentiation, adults showed dysregulation of signaling and repair pathways — indicating that gene expression abnormalities change across the lifespan in autism.

http://medicalxpress.com/news/2012-03-gene-abnormalities-autism.html

With autism, altered white matter in brain

March 7, 2012

Brain imaging and computer modeling shows how autistic brains tend to have poor quality white matter tracts connecting the frontal and posterior regions of the brain. This may explain social and language impairments.

This may mean that appropriate training could improve the white matter — compromised white matter in children with reading difficulties has been shown to be reparable with extensive behavioral therapy.

http://www.futurity.org/health-medicine/with-autism-altered-white-matter-in-brain/

Autism can be detected in babies, say scientists

A study involving six- to 10-month-old babies who had an older brother or sister with autism found that brain activity while the infants were shown faces that switched between looking at them or away from them was indicative of later diagnoses of autism.

http://www.guardian.co.uk/society/2012/jan/27/autism-detected-babies-say-scientists

http://www.eurekalert.org/pub_releases/2012-01/cp-itb012012.php

Neuroscientists find that two rare autism-related disorders are caused by opposing malfunctions in the brain

November 24, 2011

Most cases of autism are not caused by a single genetic mutation. However, several disorders with autism-like symptoms, including the rare Fragile X syndrome, can be traced to a specific mutation that leads to overproduction of proteins found in brain synapses. A new study shows that tuberous sclerosis, another rare disease characterized by autism and mental retardation, is caused by the opposite malfunction — too little synthesis of those synaptic proteins.

The findings fit into the theory that autism can be caused by a wide range of brain-synapse glitches. “The general concept is that appropriate brain function occurs within a very narrow physiological range that is tightly maintained. If you exceed that range in either direction, you have an impairment that can manifest as this constellation of symptoms, which very frequently go together — autism spectrum disorder, intellectual disability and epilepsy.”

The findings also show that not all cases of autism spectrum disorder will respond to the same kind of treatment.

http://medicalxpress.com/news/2011-11-neuroscientists-rare-autism-related-disorders-opposing.html

Research reveals autistic individuals are in fact superior in multiple areas

Articles about neurocentrism etc

http://medicalxpress.com/news/2011-11-reveals-autistic-individuals-fact-superior.html

http://www.nature.com/nature/journal/v479/n7371/full/479033a.html

http://www.nature.com/nature/journal/v479/n7371/full/479005a.html

http://www.guardian.co.uk/science/neurophilosophy/2011/oct/07/1

http://www.scientificamerican.com/article.cfm?id=the-hidden-potential-of-autistic-kids

Researchers find alterations of a single gene associated with intellectual disability, epilepsy and autistic features

October 7, 2011

A study has identified the gene MBD5 as the sole causative gene for 2q23.1 deletion syndrome. MBD5 functions in regulating the expression of many genes and is responsible for the core clinical features in these individuals, including intellectual disability, epilepsy and autism spectrum disorder. They have also shown that there is an association between autism and MBD5.

http://medicalxpress.com/news/2011-10-gene-intellectual-disability-epilepsy-autistic.html

New evidence for genetic basis of autism found

October 3, 2011

Some children with autism have a small deletion on chromosome 16, affecting 27 genes in a region of our genomes referred to as 16p11.2. The deletion -- which causes children to inherit only a single copy of the 27-gene cluster -- is one of the most common copy number variations (CNVs) associated with autism. A new study has found that deleting this set of genes in mice produces autistic-like behaviors: hyperactivity, difficulty adapting to a new environment, sleeping deficits, and restricted, repetitive behaviors.

http://medicalxpress.com/news/2011-10-evidence-genetic-basis-autism.html

Prenatal SSRI Exposure Linked to Autism Spectrum Disorder

A study suggests that use of selective serotonin reuptake inhibitors (SSRIs) during pregnancy increases the risk of autism spectrum disorder.

http://dx.doi.org/10.1001/archgenpsychiatry.2011.73

Inflexibility may give pupils with autism problems in multitasking

A study finds that young people with autism are inflexible when given multiple tasks, sticking rigidly to tasks in the order they are given to them, even when changing the order could save them time. They also had more difficulty remembering all the tasks they had to do.

http://www.eurekalert.org/pub_releases/2011-08/uos-img081511.php

The Risk of Aging Fathers

August 30, 2011

A mouse study has found that older males sire offspring with more copy number mutations in gene regions associated with developmental disorders, perhaps explaining why the children of older men have higher rates of schizophrenia and autism than those with younger fathers.

http://the-scientist.com/2011/08/30/the-risk-of-aging-fathers/

Diagnosed autism is more common in an IT-rich region

June 20, 2011

A Dutch study comparing prevalence of autism spectrum disorders in three geographical regions has found that diagnosed autism was significantly higher conditions in the IT-intensive region of Eindhoven (229 per 10,000, vs 84 per 10,000 and 57 per 10,000 in IT-lower regions — Haarlem and Utrecht).

http://medicalxpress.com/news/2011-06-autism-common-it-rich-region.html

Balance tips toward environment as heritability ebbs in autism?

July 4, 2011

A large twin study found that shared environmental factors accounted for 55% of strict autism and 58% of more broadly defined autism spectrum disorders (ASD). Genetic heritability accounted for 37% of autism and 38% of ASD. This dramatically reduces previous estimates of genetic heritability of autism from twin studies.

http://medicalxpress.com/news/2011-07-environment-heritability-ebbs-autism.html

Gene linked to severity of autism's social dysfunction

April 6, 2011

Variants in the gene GRIP1 (glutamate receptor interacting protein 1) have been found to contribute to the severity of social interaction deficits in autistic individuals. This gene regulates how fast receptors travel to a cell's surface, where they are activated by a brain-signaling chemical called glutamate, allowing neurons to communicate with one another. The finding lends support to a prevailing theory that autism spectrum disorders reflect an imbalance between inhibitory and excitatory signaling at synapses.

http://www.physorg.com/news/2011-04-gene-linked-severity-autism-social.html

Why Autism Strikes More Boys Than Girls

July 19, 2011

The marked gender imbalance in autism may related to a gene called retinoic acid–related orphan receptor-alpha (RORA), which interacts with certain types of estrogen and testosterone found in the brain. Autistic individuals tend to have low levels of RORA protein and the enzyme it produces (arom­a­tase). This enzyme converts testosterone to estrogen, but RORA is less active in the presence of tes­tosterone made RORA, and more active in the presence of estrogen. While the balance of sex hormones usually regulates RORA activity, an imbalance can be exacerbated by this feedback loop.

It’s suggested that low levels of RORA protein and enzyme result in an excess of testosterone, while most females are protected by their higher levels of estrogen.

http://www.scientificamerican.com/article.cfm?id=why-autism-strikes-more-boys-than-girls

'Most adults with autism go undiagnosed' -- new findings

The first ever general population survey of autism in adulthood has found that 9.8 per thousand adults in England meet official diagnostic criteria for autism spectrum disorder. Moreover, none of the cases with autism found knew that they were autistic or had received an official diagnosis of autism or asperger syndrome. The findings add support to the theory that autism is not increasing, diagnosis is just more common.

http://www.eurekalert.org/pub_releases/2011-05/uol-aw050411.php

Autism linked to hundreds of spontaneous genetic mutations

June 9. 2011

The most comprehensive search yet for spontaneous genetic mutations associated with autism spectrum disorders suggests that hundreds may play a part. It also finds that girls with autism tend to have many more mutated genes than boys with the disorder, suggesting that it generally takes a larger genomic change to cause autism in girls.

A particularly interesting finding was that, while deletion of a segment of chromosome 7 (specifically, 7q11.23) is associated with Williams Syndrome (marked by hypersocial behavior), duplication of this region is associated with autism.

http://www.nature.com/news/2011/110609/full/news.2011.359.html

http://medicalxpress.com/news/2011-06-genetic-keys-autism.html

http://www.scientificamerican.com/article.cfm?id=autism-genetic-mutations

How common is autism?

Great discussion of why prevalence estimates can be so different, and why diagnosing autism spectrum disorders is so difficult.

http://www.guardian.co.uk/science/blog/2011/jun/07/how-common-autism-diagnosis

Mapping data shows enhanced activity in the 'perception' part of the brain

Brain scans have determined that people with autism concentrate more brain resources in the areas associated with visual detection and identification (temporal, occipital, and parietal lobes), and conversely, have less activity in the areas used to plan and control thoughts and actions (frontal lobe).

http://www.eurekalert.org/pub_releases/2011-04/uom-nre032811.php

An autism brain signature?

May 25, 2011

A genome-wide analysis of the RNA in the brains of individuals with autism has revealed that, while gene expression in the frontal lobe normally varies significantly from that in the temporal lobe due to their different functions, this tended not to be true of autistic brains. Instead, in more than 2/3 autistic individuals, the levels of gene expression between the two lobes were homogenized, as if they had similar functions.
http://www.the-scientist.com/?articles.view/articleNo/29713/title/An-autism-brain-signature-/

New Genetics Work Challenges Basic Ideas about Mental Illness

May 17, 2011

Some background on genetic mutations — explaining single-nucleotide polymorphisms (SNPs), copy-number variants (CNVs), genome-wide association studies (GWAS), and how they’re being used in research into the causes of various disorders.

http://www.scientificamerican.com/article.cfm?id=new-genetics-work-challenges-basic-ideas-about-mental-illness

Researchers link spontaneous gene mutations to autism

May 16, 2011

Preliminary results suggest that as many as % of sporadic autism cases can be explained by spontaneous gene mutations. The findings are also consistent with other studies suggesting that ASDs are more likely in children born to older parents, and in particular, older fathers.

http://medicalxpress.com/news/2011-05-link-spontaneous-gene-mutations-autism.html

Children conceived in winter have a greater risk of autism, study finds

May 5, 2011

An examination of the birth records of children born in California during the 1990s and early 2000s has found a clear link between the month in which a child is conceived and the risk of that child later receiving a diagnosis of autism, with those conceived during winter having a significantly greater risk of autism.

Earlier studies (all much smaller) have found inconsistent results in linking autism risk to month of conception.

http://medicalxpress.com/news/2011-05-children-winter-greater-autism.html

The mirror neuron system in autism: Broken or just slowly developing?

May 3, 2011

It’s been suggested that the mirror neuron system (neurons that activate in similar ways whether we perform actions or watch other people perform the same actions) is broken in autistic individuals, but a new study suggests that it just develops more slowly.

http://medicalxpress.com/news/2011-05-mirror-neuron-autism-broken-slowly.html

An interview with mirror neuron guru Vilayanur S. Ramachandran about autism and mirror neurons.

http://scienceblogs.com/neurophilosophy/2011/03/ramachandran_broken_mirror.php

A world first: The discovery of a common genetic cause of autism and epilepsy

April 8, 2011

Researchers have identified a new gene that predisposes people to both autism and epilepsy. The synapsin gene (SYN1) plays a crucial role in the development of the membrane surrounding neurotransmitters (the synaptic vesicles), affecting communication between neurons.

http://www.physorg.com/news/2011-04-world-discovery-common-genetic-autism.html

Knowing Me, Knowing You: How Social Intuition Goes Awry in Autism

March 7, 2011 

It’s suggested that the social impairment characteristic of autism spectrum disorders may be related to a lack of a type of spindle neurons called Von Economo neurons. These neurons are only found in very social species, such as the great apes, elephants, and whales and ­dolphins, and are found only in the frontoinsular and anterior cingulate cortex.

http://www.scientificamerican.com/article.cfm?id=knowing-me-knowing-you

Cognitive skills in children with autism vary and improve, study finds

September 15, 2010

A three year study looking at how the cognitive skills of children with ASD change over time has found that most of the children (aged 5-6 at the beginning of the study) developed better appreciation of others' thoughts and feelings, and improved ability to plan, regulate, and control their thoughts and actions. However, their ability to construct patterns from wooden blocks and search for shapes hidden in pictures did not improve over time.

www.physorg.com/news203744311.html

Too Much, Too Young: Brain Overgrowth Correlates with the Severity of Autism Symptoms

July 27, 2010

Excess brain growth may be the first sign of autism, starting in the first year of life, if not sooner.

http://www.scientificamerican.com/article.cfm?id=too-much-too-young

Scientists have the genetic causes of autism in their sights

The Autism Genome Project has identified rare genetic mutations (copy number variations (CNVs)), that were 20% more frequent in children with autism than in children without the disorder.

http://www.guardian.co.uk/science/2010/jun/09/autism-study-genetic-causes

http://www.eurekalert.org/pub_releases/2010-06/uoc--wld060710.php

Alternative Biomedical Treatments for Autism: How Good Is the Evidence?

October 7, 2010

Review of alternative autism treatments.

http://www.scientificamerican.com/article.cfm?id=alternative-biomedical-treatments

A Crack in the Mirror Neuron Hypothesis of Autism

May 12, 2010

A new test of mirror neuron activity suggests that autistic individuals’ mirror neurons may behave normally. However, they showed more variable activity in brain regions that process visual images and execute movements. The researchers suggest that it may be faulty signaling, rather than mirror neuron problems, that underlies some of their social difficulties.

The researchers’ tests and interpretations are controversial.

http://news.sciencemag.org/sciencenow/2010/05/a-crack-in-the-mirror-neuron-hyp.html?etoc

Video Q&A: What is autism? - A personal view

http://www.biomedcentral.com/1741-7007/8/42

Stem cells restore cognitive abilities impaired by brain tumor treatment

A rat study has found that transplanted stem cells restored learning and memory to normal levels four months after radiotherapy. This compares with a greater than 50% decline in cognitive function in those rats that didn’t receive the therapy. Cranial irradiation is a common treatment for brain tumors.

[803] Acharya MM, Christie L-A, Lan ML, Donovan PJ, Cotman CW, Fike JR, Limoli CL. Rescue of radiation-induced cognitive impairment through cranial transplantation of human embryonic stem cells. Proceedings of the National Academy of Sciences [Internet]. 2009 ;106(45):19150 - 19155. Available from: http://www.pnas.org/content/early/2009/11/06/0909293106.abstract

http://www.eurekalert.org/pub_releases/2009-11/uoc--scr110509.php

Childhood brain tumors permanently impact cognition & lifestyle

A survey involving 785 CNS cancer survivors, 5,870 survivors of non-CNS cancers (such as leukemia, Hodgkin's disease, and bone tumors), and 379 siblings of CNS cancer survivors, sent at least 16 years after diagnosis, has found that CNS cancer survivors reported significantly greater neurocognitive dysfunction than their siblings and survivors of other types of cancer. Moreover, these problems were linked to lower achievement in education and in full-time employment and income, as well as less chance of being married. The worst problems were found in those who had tumors in the cortex, and those who had cranial radiation treatment.

Ellenberg, L. et al. 2009. Neurocognitive Status in Long-Term Survivors of Childhood CNS Malignancies: A Report From the Childhood Cancer Survivor Study. Neuropsychology, 23 (6), 705-717.

http://www.eurekalert.org/pub_releases/2009-11/apa-bti102709.php

Therapy program has significant effect on autistic toddlers

A randomized controlled trial involving autistic toddlers aged 18 to 30 months has found that those who participated for two years in an intensive program of behavioral therapy known as the Early Start Denver Model improved 17.6 standard score points in IQ, on average, compared with 7 points in the group who received standard community intervention. They were also more likely to be re-diagnosed from autism to pervasive developmental disorder.

[1499] Dawson G, Rogers S, Munson J, Smith M, Winter J, Greenson J, Donaldson A, Varley J. Randomized, Controlled Trial of an Intervention for Toddlers With Autism: The Early Start Denver Model. Pediatrics [Internet]. 2010 ;125(1):e17-23 - e17-23. Available from: http://pediatrics.aappublications.org/cgi/content/abstract/125/1/e17

http://www.newscientist.com/article/dn18221-treating-toddlers-for-autism-boosts-iq-later.html

Study finds autistics better at problem-solving

A study involving 15 autistics and 18 non-autistics, aged 14 to 36 and IQ-matched, has found that while both groups completed patterns in a complex problem-solving test (the widely-used Raven's Standard Progressive Matrices) with equal accuracy, the autistics responded significantly faster, and showed a different pattern of brain activity. Specifically, they showed increased activity in extrastriate areas, and decreased activity in the lateral prefrontal cortex and the medial posterior parietal cortex — suggesting visual processing mechanisms may play a more prominent role in reasoning in autistics. The differences between groups did not appear when participants performed a simpler pattern-matching task.

[555] Soulières I, Dawson M, Samson F, Barbeau EB, Sahyoun CP, Strangman GE, Zeffiro TA, Mottron L. Enhanced visual processing contributes to matrix reasoning in autism. Human Brain Mapping [Internet]. 2009 ;30(12):4082 - 4107. Available from: http://dx.doi.org/10.1002/hbm.20831

http://www.eurekalert.org/pub_releases/2009-06/uom-sfa061609.php

New genes implicated in autism; support new theory of cause

Research involving 104 large Middle Eastern families has implicated half a dozen new genes in autism, and more importantly, strongly supports the emerging idea that autism stems from disruptions in the brain's ability to form new connections in response to experience – consistent with autism's onset during the first year of life, when many of these connections are normally made. Just over 6% of the 88 families with autistic members showed rare, inherited deletions within DNA regions linked to autism. These affected DNA regions varied among families, further indication of autism's large variety of genetic causes. In all, the technique identified five chromosome deletions affecting at least six identifiable genes. Although the genes discovered are diverse in function, all seem to be part of a fundamental network that orchestrates the refinement and maturation of synapses in response to input from the outside world. The network itself is already known to activate at least 300 genes, so it’s no surprise that there are many ways it can be disrupted, explaining why there might be myriad genetic causes of autism, even though in essence it might be all the same problem: a disruption of the brain's ability to modify its synaptic connections in response to experience. The good news is that in all but one case the chromosome deletions didn’t actually remove a gene, they just turned it off — suggesting a possible ‘cure’ if researchers can figure out how to turn them back on.

[942] Hashmi A, Al-Saad S, Ware J, Joseph RM, Greenblatt R, Gleason D, Ertelt JA, Apse KA, Bodell A, Partlow JN, et al. Identifying Autism Loci and Genes by Tracing Recent Shared Ancestry. Science [Internet]. 2008 ;321(5886):218 - 223. Available from: http://www.sciencemag.org/cgi/content/abstract/321/5886/218

http://www.eurekalert.org/pub_releases/2008-07/chb-mef070808.php

Autism's social struggles due to disrupted communication networks in brain

And a timely imaging study has now provided the clearest evidence to date that synchronization in what might be termed the Theory of Mind network is impaired in autistic people. The Theory of Mind network (which includes the medial frontal gyrus, the anterior paracingulate, and the right temporoparietal junction) is responsible for processing the intentions and thoughts of others. In the study 12 high-functioning autistic adults and 12 controls viewed animated interacting geometric figures, and then asked to select the word from several choices that best described the interaction. The control subjects were consistently better at inferring the intention from the action than the participants with autism were. Brain scans revealed that synchronization between the frontal and posterior regions in the network was reliably lower in the group with autism. The autistic participants' brains also showed much lower activation levels in the frontal regions, and an independent assessment of their Theory of Mind abilities found these reliably correlated with activation in the right temporoparietal junction. The findings point to the need to develop interventions that could target this problem, and also indicate a way to measure an intervention’s effectiveness.

[782] Kana RK, Keller TA, Cherkassky VL, Minshew NJ, Just MA. Atypical frontal-posterior synchronization of Theory of Mind regions in autism during mental state attribution. Social Neuroscience [Internet]. 2009 ;4(2):135 - 152. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18633829

http://www.eurekalert.org/pub_releases/2008-07/cmu-ass072308.php

New genetic link to autism identified

Three new studies, using different methods, have all implicated the same gene in the development of autism. The research follows earlier findings implicating a specific region of Chromosome 7 called 7q35. The gene — contactin-associated protein-like 2 (CNTNAP2) — is a gene in this region. The research not only points to this gene predisposing an individual to autism, it also may explain the association with late language onset, a characteristic of most autistic children. The gene was most active in developing brain structures involved in language and thought. The finding may also help explain why autism is so much more common among boys. Statistical evidence for the gene was strongest in families with autistic boys. Less of an association appeared in families with autistic boys and girls, or in families with autistic girls only.

[902] Ledbetter DH, Alarcón M, Abrahams BS, Stone JL, Duvall JA, Perederiy JV, Bomar JM, Sebat J, Wigler M, Martin CL. Linkage, Association, and Gene-Expression Analyses Identify CNTNAP2 as an Autism-Susceptibility Gene. The American Journal of Human Genetics [Internet]. 2008 ;82(1):150 - 159. Available from: http://www.cell.com/AJHG/abstract/S0002-9297(07)00011-0

[538] Cook Jr. EH, Arking DE, Cutler DJ, Brune CW, Teslovich TM, West K, Ikeda M, Rea A, Guy M, Lin S. A Common Genetic Variant in the Neurexin Superfamily Member CNTNAP2 Increases Familial Risk of Autism. The American Journal of Human Genetics [Internet]. 2008 ;82(1):160 - 164. Available from: http://www.cell.com/AJHG/abstract/S0002-9297(07)00021-3

[857] Stillman AA, Bakkaloglu B, O'Roak BJ, Louvi A, Gupta AR, Abelson JF, Morgan TM, Chawarska K, Klin A, Ercan-Sencicek GA. Molecular Cytogenetic Analysis and Resequencing of Contactin Associated Protein-Like 2 in Autism Spectrum Disorders. The American Journal of Human Genetics [Internet]. 2008 ;82(1):165 - 173. Available from: http://www.cell.com/AJHG/abstract/S0002-9297(07)00023-7

http://www.eurekalert.org/pub_releases/2008-01/uoc--usi010808.php

Autism non-verbal not unintelligent

New findings suggest that the association of autism with low intelligence is a product of their language difficulties. Testing autistic kids and normal kids on two popular IQ tests — the WISC (which relies heavily on language) and Raven's Progressive Matrices (considered the best test of "fluid intelligence", and a test that doesn't require much language) found that while not a single autistic child scored in the "high intelligence" range of the WISC, a third did on the Raven's. A third of the autistics had WISC scores in the mentally retarded range, but only one in 20 scored that low on the Raven's test. The non-autistic children scored similarly on both tests. The same results occurred when the experiment was run on autistic and normal adults.

[580] Dawson M, Soulières I, Gernsbacher MA, Mottron L. The level and nature of autistic intelligence. Psychological Science: A Journal of the American Psychological Society / APS [Internet]. 2007 ;18(8):657 - 662. Available from: http://www.ncbi.nlm.nih.gov/pubmed/17680932

http://www.physorg.com/news105376203.html
http://www.eurekalert.org/pub_releases/2007-08/afps-tmo080307.php

Monkeys can reflect on their thoughts

A study involving two rhesus macaque monkeys has shown that a monkey can reflect on its own thoughts and assess its performance. The experiment trained the monkeys to play a video game that tested their ability to remember a particular photograph while also allowing them to make a large or a small bet on how likely they were to be right. The monkeys could also request hints for problems that would otherwise have to be solved by trial and error. Not only did the results provide clear evidence of their ability to engage in metacognition, but the study also points to a means of testing nonverbal humans, such an infants and autistic children.

[1315] Kornell N, Son LK, Terrace HS. Transfer of metacognitive skills and hint seeking in monkeys. Psychological Science: A Journal of the American Psychological Society / APS [Internet]. 2007 ;18(1):64 - 71. Available from: http://www.ncbi.nlm.nih.gov/pubmed/17362380

http://www.eurekalert.org/pub_releases/2007-04/afps-mat042007.php

Oxytocin may help treat two core autism symptoms

In a pilot study, researchers have found administration of oxytocin has beneficial effects on repetitive behaviors and aspects of social cognition in high-functioning autistic adults.

The research was presented at the American College of Neuropsychopharmacology's Annual Meeting.

http://www.eurekalert.org/pub_releases/2006-12/g-nrs120106.php

A gene for autism

A study has found that those with two copies of a specific variant of a gene within chromosome 7, that regulates production of a protein that influences cell proliferation in various parts of the body, are substantially more likely to be autistic. The link between the MET variant and autism appears primarily in families with two or more affected children. The gene variant is not rare — roughly 47% of the population carry at least one copy of it. It may be that it is affected by prenatal environmental factors or that it interacts with other genes to derail brain formation. It is likely that there are a number of genes associated with autism. But this particular gene variant would explain controversial reports that people with autism often have immune and gastrointestinal problems.

[692] Sacco R, Persico AM, Levitt P, Campbell DB, Sutcliffe JS, Ebert PJ, Militerni R, Bravaccio C, Trillo S, Elia M, et al. A genetic variant that disrupts MET transcription is associated with autism. Proceedings of the National Academy of Sciences [Internet]. 2006 ;103(45):16834 - 16839. Available from: http://www.pnas.org/content/103/45/16834.abstract

http://www.sciencenews.org/articles/20061021/fob1.asp

Brain enlargement may be characteristic of autism

Comparison of 164 children with autism and 214 control children (all younger than 3 years) has found significant enlargement in the volume of the cerebral cortex, in both white and grey matter, and generalized throughout the cortex. Head circumference was not significantly different at birth — an increased rate of growth occurred from around 12 months.

[315] Hazlett HC, Poe M, Gerig G, Smith RG, Provenzale J, Ross A, Gilmore J, Piven J. Magnetic Resonance Imaging and Head Circumference Study of Brain Size in Autism: Birth Through Age 2 Years. Arch Gen Psychiatry [Internet]. 2005 ;62(12):1366 - 1376. Available from: http://archpsyc.ama-assn.org/cgi/content/abstract/62/12/1366

http://www.eurekalert.org/pub_releases/2005-12/jaaj-bem120105.php

Breakdown of myelin insulation in brain's wiring implicated in childhood developmental disorders

Previous research has suggested that the production of myelin (a fatty insulation coating the brain's internal wiring) is a key component of brain development through childhood and well into middle age, when development peaks and deterioration begins, and that midlife breakdown of myelin is implicated to onset of Alzheimer's disease later in life. Now new research suggests the disruption of myelination is a key neurobiological component behind childhood developmental disorders, such as autism and attention deficit/hyperactivity disorder, and addictive behaviors. The analysis also suggests that alcohol and other drugs of abuse have toxic effects on the myelination process in some adolescents.

Bartzokis, G. 2005. Adolescent Psychiatry. Hillsdale, N.J.: The Analytic Press Inc.

http://www.eurekalert.org/pub_releases/2005-11/uoc--bom111405.php

Why autism is associated with executive function problems

A new imaging study has revealed that autistic boys have less activation in the parts of the brain responsible for executive function (attention, reasoning and problem solving) — specifically, in the caudate nucleus, a critical part of circuits that link the prefrontal cortex of the brain. The researchers have noted similarities in the impairment of specific executive function in children with ADHD and autism.

[2574] Silk T, Rinehart N, Bradshaw J, Tonge B, Egan G, O’Boyle M, Cunnington R. Visuospatial Processing and the Function of Prefrontal-Parietal Networks in Autism Spectrum Disorders: A Functional MRI Study. American Journal of Psychiatry [Internet]. Submitted ;163(8):1440 - 1443. Available from: http://ajp.psychiatryonline.org/article.aspx?articleid=96920

http://www.eurekalert.org/pub_releases/2005-10/ra-ape102305.php

Finding supports theory that autism results from failure of brain areas to work together

An imaging study indicates people with autism remember letters as geometric shapes, compared to the more usual remembering by their names. Moreover, compared to the control group, the activated brain areas of the people with autism were less likely to work in synchrony (at the same time) while recalling the letters. This supports a theory that autism results from a failure of the various parts of the brain to work together. This theory suggests that therapies emphasizing problem solving skills and other tasks that activate multiple brain areas at the same time might benefit people with autism.

Koshino, H., Carpenter, P.A., Minshew, N.J., Cherkassky, V.L., Keller, T.A. & Just, M.A. 2005. Functional connectivity in an fMRI working memory task in high-functioning autism. NeuroImage, 24 (3), 810-821.

http://www.eurekalert.org/pub_releases/2004-11/nioc-bop112904.php

Special training may help people with autism recognize faces

People with autism tend to activate object-related brain regions when they are viewing unfamiliar faces, rather than a specific face-processing region. They also tend to focus on particular features, such as a mustache or a pair of glasses. However, a new study has found that when people with autism look at a picture of a very familiar face, such as their mother's, their brain activity is similar to that of control subjects – involving the fusiform gyrus, a region in the brain's temporal lobe that is associated with face processing, rather than the inferior temporal gyrus, an area associated with objects. Use of the fusiform gyrus in recognizing faces is a process that starts early with non-autistic people, but does take time to develop (usually complete by age 12). The study indicates that the fusiform gyrus in autistic people does have the potential to function normally, but may need special training to operate properly.

Aylward, E. 2004. Functional MRI studies of face processing in adolescents and adults with autism: Role of experience. Paper presented February 14 at the annual meeting of the American Association for the Advancement of Science in Seattle.

Dawson, G. & Webb, S. 2004. Event related potentials reveal early abnormalities in face processing autism. Paper presented February 14 at the annual meeting of the American Association for the Advancement of Science in Seattle.

http://www.eurekalert.org/pub_releases/2004-02/uow-stm020904.php

Autistic preschoolers don't recognize emotions from facial photographs

Normally developing infants notice their mothers' facial expressions and emotions in the first six months of life and are able to recognize emotions from facial expressions by age 7 months. In a recent study reported at the first International Meeting for Autism Research in San Diego last month, 3- and 4-year-old autistic, developmentally delayed and normally developing children were shown photographs of faces depicting fear and a neutral expression while brain activity was monitored. It was found that the brains of normally developing and developmentally delayed children exhibited different activity depending on the picture being viewed. However, the brain activity of the autistic children remained the same when the different pictures were shown.

Dawson, G. & Dager, S. 2001. Paper presented at the first International Meeting for Autism Research in San Diego in November. The autism meeting was held in conjunction with the annual meeting of the Society for Neuroscience.

http://www.eurekalert.org/pub_releases/2001-12/uow-ahl120401.php

Differences in face perception processing between autistic and normal adults

An imaging study compared activation patterns of adults with autism and normal control subjects during a face perception task. While autistic subjects could perform the face perception task, none of the regions supporting face processing in normals were found to be significantly active in the autistic subjects. Instead, in every autistic patient, faces maximally activated aberrant and individual-specific neural sites (e.g. frontal cortex, primary visual cortex, etc.), which was in contrast to the 100% consistency of maximal activation within the traditional fusiform face area (FFA) for every normal subject. It appears that, as compared with normal individuals, autistic individuals `see' faces utilizing different neural systems, with each patient doing so via a unique neural circuitry.

[704] Pierce K, Muller R-A, Ambrose J, Allen G, Courchesne E. Face processing occurs outside the fusiform `face area' in autism: evidence from functional MRI. Brain [Internet]. 2001 ;124(10):2059 - 2073. Available from: http://brain.oxfordjournals.org/cgi/content/abstract/124/10/2059

http://brain.oupjournals.org/cgi/content/abstract/124/10/2059

Autistic 3- and 4-year-olds react to a picture of a familiar toy but not to a picture of their mother

Face recognition is a specialized and highly developed memory system in humans, and a preference for face-like stimuli is evident even in newborn babies. New research has found that, unlike normally developing and even mentally retarded children, autistic 3- and 4-year-olds do not react to a picture of their mother, although they do react when they see a picture of a familiar toy. This highlights that autism is a disorder of the social brain, and may allow diagnoses of autism to be made much earlier than is now possible.

The study was reported at the annual meeting of the Society for Research in Child Development.

http://www.eurekalert.org/pub_releases/2001-04/UoW-Mija-1604101.php