Autistic Brains Are Bigger

An interesting study came out a few days ago. It looked at the brains of autistic kids postmortem and found that they had bigger brains with more neurons than in neurotypicals. Why is still an unknown, and how this causes the symptoms of autism is also unknown. (Though there are hints of connections to excess and perhaps in the wrong places).

This came as a bit of a surprise to some folks, but for me it was more of confirmation than surprise. Kids with autism have long been known to have larger heads and bigger brain volume. This study extends that to the number of neurons. I’ve also put forward the thesis that on the ‘spectrum’ from normal to autistic you pass through the ‘little professors’ of Aspbergers. Folks who have brains that generally show more reasoning function than the average (though with the loss of some social behaviours – such as having a more formal ‘style’ of social interaction and taking things rather too literally).

Looked at as a spectrum, we see increasing brain function and increasing capacity for things like absorbing large and complex bodies of information – THEN things go off the rails as the ‘spectrum’ reaches the Rainman range of the autistic. Yet the savants in that end can do things like memorize phone books and calculate days of the year for any year. Things that show more function than ‘typical’ in those areas.

Also, on a more anecdotal level, in my spouse’s experience in Silicon Valley, there are a large number of kids with autism who have two parents with high cognitive function, but often a bit on the Aspergers side of things. In essence, two “Geeks”. To me, this tendency indicated a trait where ‘a little bit is good, too much causes problems’.

I’ve used the example before of epilepsy. There is some property that causes increasing irritation at a 3 CPS / Hz flashing light. Eventually, with enough of that property, the person will show ‘pre-seizure’ activity and in the limit case be triggered into an epileptic episode. Folks expected to find a spectrum of increasing irritation in folks with some precursor ‘problem’. Basically, they expected to find that there was something wrong that got worse with more of ‘the property’, whatever it was. What they found instead was that THE group with the highest tendency to ‘irritation’ but without seizure indications was professional airline pilots. Paragons of function. A little was good, very good. It came with the fast reflexes and swift decision making needed to be a pilot. Too much was the problem… This, too, was not such a surprise since even from ancient times it was recognized that folks like Caesars would have more epilepsy than commoners.

So, IMHO, we’ve found another one of those. A little more of the trait, you get better memory skills, large and in depth grasp of problems, increased ability to focus in depth on an issue and ‘worry it to an end’. The “gifted” folks who make up much of our top technical tier. (And also dominate Mensa). However, too much and you get an eventual breakdown of social function. A tendency to focus on some ‘issue’ to the exclusion of all else, and I do mean all. Such as memorizing a phone book and not wanting to stop reading it until it is totally absorbed, even if that means not eating.

As I’ve pointed out before, empathy can be quite strong. I would assert that for some, the empathetic bond can be too cruel. Knowing that someone is hurting, and being unable to change that, is a hard thing. Worse is knowing that someone is hurting others, and knowing that you can do nothing about it. IMHO, it is the gestalting of the hopelessness of humanity at too early a life stage that causes some autistics to withdraw into isolation.

It’s a cruel world out there, and the loonies are in charge of it. Hard to swallow at any age… Knowing that the ideal answer to ‘where to sit’ exists, yet being told by everyone around you that it does not, and is not important, is at best wearing. So to contemplate something like “what is life for?” can become both escape and occupier of the mind; both liberator and anesthesia. Some of us do that for ‘medicinal purposes’ and some IMHO look like they get hooked on the drug and do it to the point of mental consumption… for them it may become tormentor (and that the answer can be dismal is not helpful, so some folks escape into religion – but what if the answer is dismal AND religion is already understood to be a bit daft?). Basically, some of us can handle the truth, for others “The truth, you can’t handle the truth” is all too true. Followed by withdrawal into another place.

There is one other aspect to this. Synesthesia. Many Aspergers and high function Autistics have said that they have a kind of synesthesia. Where numbers have colors or tastes, for example, and the right answer will just ‘smell right’. If there is, in fact, so many neurons that they can’t get out of each others way and let more ‘normal’ connections be made, perhaps they also function as those unexpected pathways of synesthesia? Connecting sound and taste, math and color, things that are sensed with things that are thought. This could explain a lot.

OK, enough ‘ramble’. Some pointers to the source information:

By CARRIE GANN (@carrie_gann) , ABC News Medical Unit
Nov. 8, 2011

A new, small study provides a tantalizing clue to the causes of autism, suggesting that children with the disorder have heavier brains and an overabundance of brain cells called neurons.

Autism researchers had suspected for more than a decade that the disorder might be the result of abnormal brain growth and development. Previous studies have shown that autistic children have larger heads and brains, and that brain regions crucial for social, emotional, and communication processing are particularly overgrown. But this study is the first to provide hard evidence of brain development gone awry in autistic children, gleaned from actual counts of these brain cells.

The article goes on from there. Nicely written and easy to read. A good blend of technical information with the interpretation of it. Such as this bit:

They found that the brains of the autistic children had 67 percent more neurons in a region called the prefrontal cortex, an area linked to social, emotional, and communication processing — functions that are typically lacking in autism.

The brains of the autistic children also weighed an average of 17.5 percent more than the brains of children without the disorder.

Quotes snippets of the original article and includes some interesting ‘connections’ bits. They also inform us that the original is published in the “November 9 issue of the Journal of the American Medical Association.”

“Factors that normally organize the brain appear to be disrupted,” said an accompanying editorial by Janet Lainhart of the University of Utah and Nicholas Lange of the Harvard University Schools of Medicine and Public Health.

Previous studies have suggested that clinical signs of autism tend to coincide with a period of abnormal brain and head growth that usually becomes apparent at nine to 18 months of age, according to the article.

Autism includes a wide spectrum of developmental differences and may range from mild social awkwardness to complete inability to communicate, repetitive movements, sensitivity to certain lights and sounds, and behavioral problems.

And what of the ‘epidemic’ of autism? Well, I can speculate on many potential factors that taken together could all be part of the ‘problem’. Beyond just the tendency recently to judge most everything as ‘on the spectrum’ (including ‘mild social awkwardness’ – who hasn’t been awkward at times?); for those that actually ARE on the spectrum:

First off, we have a potential for a genetic component. “When two geeks marry”, you may push the trait to larger brain size and a ‘little bit of social awkwardness’ over the edge into a ‘fit of awkwardness’… So yes, I’m suggesting that the geeks ought to be marrying in to the cheerleaders and football players. We both need each other and separating into inbreeding clans is not a good thing. One ends up on a slow slide to stupidity, the other on a fast track to mental implosion.

On the environmental front, it is at least a little bit possible that our very rich and full diets in the modern world are not always all that great. Take a brain that is expecting to be starved, that is genetically programed to ‘over grow’ by 10% to make up for the tendency for famine to cause small brain sizes, then over feed it? Yeah, I can see where that could be a problem…

But it may not be that simple. The articles go on to mention that there is a developmental stage of brain over growth during pregnancy, followed by apoptosis to weed out some of the tissues. In a sense, to mill it to the end functional connections. It is also possible that some environmental agents are reducing that functional step. Interference with that step would cause not just ‘too much’ but also ‘in the wrong place’ problems. The folks with kinesthesia, for example. Tissue growth and development can be hideously sensitive to environmental chemicals that are of no consequence at all to other stages of life. It is fairly well established, for example, that a diet rich in fish and their omega-3 fatty acids aid brain development in infants.

Has a nice write-up of how the developing fetus can scavenge omega-3 from the mother and store it to excess as it is needed for brain development.

The wiki has an interesting snippet too:

DHA deficiency is associated with cognitive decline Phosphatidylserine (PS) controls apoptosis, and low DHA levels lower neural cell PS and increase neural cell death. DHA are reduced in the brain tissue of severely depressed patients.

That “controls apoptosis” part. So we have a potential failure of apoptosis at a key point in fetal brain development along with a dietary substance that can control apoptosis… So the potential exists for too high a level of PS causing too low a level of apoptosis (perhaps limited to only a genetic subset of the population). Or an environmental agent could act on the same pathways as PS so as to interfere with the ‘control’. It would not harm an adult (as we’re not interested in having our brain cells die…) but could easily be a problem in the developing fetus…

In Conclusion

While it’s not exactly a ‘smoking gun’ pointing to a ‘cure’, this does point in the direction of where to look. It gives some clues about why we might be having an ‘epidemic’ now (beyond just ‘over diagnosis’) and if nothing else, it’s at least an interesting bit on the path to understanding.

It also does, once again, confirm the truth that sometimes “less is more”…

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About E.M.Smith

A technical managerial sort interested in things from Stonehenge to computer science. My present "hot buttons' are the mythology of Climate Change and ancient metrology; but things change...
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6 Responses to Autistic Brains Are Bigger

  1. Scarlet Pumpernickel says:

    Low Vitamin D could have some connection, in either the pregnant mother or the child? In terms of why it’s getting worse?

  2. Scarlet Pumpernickel says:

    If the brain is bigger, is that why they take longer to develop when young, eg speech takes longer? As they have more neurons to organise then an average person, so they are delayed initially then later have more capacity ?

  3. xyzlatin says:

    With the development of more people going to higher education, the internet where there are dating sites where literally hundreds of thousands of people can advertise to others, and the explosion of technical jobs and technology and computing, where they can congregate, the “geeks” are able to find each other and breed, unlike human development before the internet age. If your theory is correct about the resulting autism of their children, then its incidence will increase.
    A very interesting post, thanks.

  4. adolfogiurfa says:

    Then, politicians do not suffer of autism :-)

  5. PhilJourdan says:

    It makes sense to me as well. Thinking too much so that you stop being able to function. I went to school with a guy who was a genius. And he could barely talk. His brain just worked too fast.

  6. R. Shearer says:

    Too many underfed brains or overfed egos in Washington.

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