This week’s podcast focuses on the Extreme Male Brain Theory of autism, originating from the idea that autism, in part, is a reflection of increased fetal testosterone levels.  Amazingly, fetal testosterone levels are reflected in the length of the 2nd and 4th fingers and can be measured as a reflection of testosterone levels during pregnancy. Research, including those from a recent CDC study, have reinforced that elevated fetal testosterone levels play a role in autism in males, but not females.  Differences in fetal testosterone across gender and diagnosis has also been observed in a study from Drexel University.  What was observed in males is not observed in females.  It doesn’t mean the theory is wrong, it means that what is true for one sex is not always true for the other.

https://www.ncbi.nlm.nih.gov/pubmed/29450837

 

The media accurately described a recent study from Dan Geschwind’s lab at UCLA as “groundbreaking”.  That’s because the findings help people with autism better understand how and why their symptoms are different to other mental conditions, specifically bipolar depression and schizophrenia.  It turns out the gene expression patterns in the brains of people with autism are similar to those with bipolar depression and schizophrenia, but not alcoholism or major depression.   It also offers hope for a more accurate biological signature of autism that can be distinguished from bipolar depression and schizophrenia.    Below is a graph that represents these different profiles, and if you want to read a version of the article that is available online (but before it was peer reviewed in the journal Science) you can find it here: https://www.biorxiv.org/content/biorxiv/early/2016/02/18/040022.full.pdf 

This week, the lab of Dr. Jill Silverman at UC Davis published a study that showed the most similar types of social communication deficits in an animal model.  Her group, led by Elizabeth Berg, used a rat model, rather than a mouse, because rats exhibit both receptive and expressive communication.  Through a collaboration within the UC Davis MIND Institute and Mount Sinai School of Medicine, she tested an animal model of autism that shows a lack of expression of SHANK3.  SHANK3 mutations are seen in those with Phelan-McDermid Syndrome as well as in 1% of people with autism.  This new study opens up new ways to understand autism symptoms in an animal model, and moves autism research using animals forward significantly.   The references mentioned in the podcast are:

 

https://www.ncbi.nlm.nih.gov/pubmed/29377611

https://www.ncbi.nlm.nih.gov/pubmed/29126394

https://www.ncbi.nlm.nih.gov/pubmed/27189882

This week, former ASF fellow Katherine Stavropoulos from UC Riverside and Leslie Carver published data investigating what is the core cause of social communication deficits in autism.  Do people with autism show deficits in this area because they have a lack of motivation for social cues, or are social interactions just too overwhelming on their senses?  It turns out, both are true and this has direct implications for intervention methods.  Also, parents and siblings of people with autism show subtle symptoms of ASD without having a diagnosis.  This is called the broader autism phenotype, and a study by the Study to Explore Early Development led by Dr. Eric Rubenstein, demonstrated that parents of children with a particular group of symptoms are more likely to show this phenotype than other groupings.  You can read the full studies here:

 

https://molecularautism.biomedcentral.com/articles/10.1186/s13229-018-0189-5

https://www.ncbi.nlm.nih.gov/pubmed/29376397

 

It’s well known that both parent report and observational measure are crucial to an autism diagnosis.  But what about prior to a diagnosis, in the critical period of 12-18 months when symptoms may be seen but a diagnosis cannot yet be made?  A research collaboration across Canada has been studying better detection and translating it to early intervention, and postdoc Lori Sacrey from University of Alberta took the lead on a multi-site study investigating the utility and contribution of a parent report measure together with an observational tool in toddlers.  She found that the parent report measure provided insights which improved the ability to predict a later autism diagnosis.  It is because of the collaboration across Canada that this research is possible.  Also, the autism journal Autism took an unusual and bold step in ensuring that adults with autism are represented in their perspective.  Hear why on this week’s podcast or read the link below:

http://journals.sagepub.com/doi/pdf/10.1177/1362361317748556 

Here is the Sacrey publication:  https://www.ncbi.nlm.nih.gov/pubmed/29356441

 

Often overlooked in intervention studies, it is becoming increasingly clearer that adaptive behavior, the “will do” vs. the “can do” of functioning, should receive more focus.  In people with autism and high IQ, cognitive ability, the “can do” is higher than adaptive behavior, the “will do”.  Why?  The key in new research from the National Institutes of Health may be social abilities.  Another study this week from Children’s Hospital of Philadelphia in adult  with high IQ demonstrates that social motivation may be the key to improving social skills and socialization in people with ASD.

Paid support staff are critical to helping individuals at all ages with autism.  Unfortunately, they are mostly poorly paid, and exhibit high levels of burnout.  What psychological constructs are most important, and can they be targeted for services to help provide better services for those with ASD?  As it turns out, more important than preventing burnout is building up psychological capital, which helps deal with the effects of burnout.  In addition, a new important feature of autism has been identified: intolerance to uncertainty.  Previously linked to ASD through anxiety, now it is shown to have direct connections to ASD diagnosis and symptomatology.  Is this a new core feature?

Unfortunately this podcast does not really provide an answer, but does highlight data published over the holidays which shows in another dataset, that the prevalence of autism seems to be leveling out, rather than continue to increase as it has done for the past several decades.  It isn’t the final word and clearly there may be exceptions, but now two national datasets have shown no further increase in autism prevalence in the last few years of looking.  Is it 1:68 as reported in one study or 1:39 in another?  Is it somewhere in between?  Still to early to say, but white boys seem to be the most likely to get a diagnosis no matter where you look.  Also, folic acid proves to show an effect on the probability of not just an autism diagnosis, but autism symptoms.  This is especially important for women taking anti epileptic medications for seizures and bipolar depression.  Welcome to 2018!

Here are links to the articles.  Some of them are open access!

https://www.ncbi.nlm.nih.gov/pubmed/29297068

https://www.cdc.gov/nchs/data/databriefs/db291.pdf

https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2667432

https://www.ncbi.nlm.nih.gov/pubmed/29279889

 

 

In 40 minutes, ASF summarizes the highlights in autism research from before diagnosis through adulthood.   It includes new intervention studies, ways to better diagnose ASD, to understand symptoms, females, sexuality, employment, neurobiology, genetics, and gene x environment interactions.   The major themes are the “H” word, or heterogeneity in symptoms across the spectrum, ways to make the broad spectrum smaller, and how big data approaches are helping make this happen.  Thank you to families who participated in research and tireless autism researchers for lending their skills to answer the tough questions.  And of course, thank you all for listening to these podcasts all year long.  The transcript with all the references used will be posted on the ASF blog in the upcoming days.

Gamma waves are brainwave activity at a certain speed and have been linked to consciousness and seem to help coordinate activity in different parts of the brain.  They have also been associated with processing of information, including sensory information.  This week, researchers at Oxford University led by Dr. David Menassa explore gamma waves in the brains of autistic adults who perform better on a visual processing task than those without a diagnosis.  Gamma waves are controlled by the coordinated activity of neurons in the brain, which are regulated by inhibitory interneurons which make sure excitatory neurons aren’t taking over.  In a study using brain tissue of people with autism, it was found by another study at Oxford that there are fewer of these inhibitory interneurons to control this activity.  Dr. David Menassa provides his own interpretation of the data on this week’s podcast.