You may,
like me, have wondered why so much autism research seems to mention Fragile-X
syndrome and Retts syndrome.
Both
Fragile-X and Retts are caused by the mutation of single genes, FMR1 and MECP2
respectively. Autism can be caused by
very many, seemingly unrelated things, both genetic and environmental.
When you
look at it objectively, there is a much closer comparison for autism, it is schizophrenia.
I know from the research I am reading that in
fact autism and schizophrenia are intertwined and there is no boundary were one
stops and the other starts. Most likely
some of the individual biological dysfunctions in autism are present in a
greater/lesser degree in schizophrenia and vice versa. This will be developed in later posts.
For those
interested in learning more about schizophrenia here is a nice PowerPoint
presentation.
Here are some excerpts:-
·
A
biological disorder of the brain which causes disturbances in thinking, speech,
perception of reality, emotion (mood), and behavior.
·
Approximately
1% of the population develops schizophrenia during their lifetime.
·
Although
schizophrenia affects men and women with equal frequency, the disorder often
appears early in men (usually late teens), than women (generally late
twenties/early thirties).
The most
ASD-like sub-type is called disorganized
schizophrenia; and it principal features are:-
•
Confusion
and Incoherence
•
Severe
deterioration of adaptive behavior
–
Lack
of social skills
–
Poor
personal hygiene & self-care
•
Behavior
appears silly and/or child-like
•
Highly inappropriate emotional responses
It is not
hard to see the potential overlap between ASD and Disorganized Schizophrenia.
We even have
a researcher suggesting a very similar strategy for Schizophrenia, to that I am
proposing/developing for autism.
The discovery of the
pathophysiology(ies) for schizophrenia is necessary to direct rational
treatment directions for this brain disorder. Firm knowledge about this illness is limited to
areas of phenomenology, clinical electrophysiology, and genetic risk; some
aspects of dopamine pharmacology, cognitive symptoms, and risk genes are known.
Basic questions remain about diagnostic heterogeneity, tissue neurochemistry,
and in vivo brain function.
It is an illness ripe for molecular characterization using a rational approach
with a confirmatory strategy; drug discovery based on knowledge is the only way
to advance fully effective treatments. This paper reviews the status of
general knowledge in this area and proposes an approach to discovery, including
identifying brain regions of dysfunction and subsequent localized,
hypothesis-driven molecular screening.
For psychiatrists,
the main difference between autism and schizophrenia seems to be when is the onset of symptoms. Autism strikes at the age of two or three,
whereas schizophrenia occurs much older.
Whether in fact some of the same biological mechanisms might be at work
does not seem to be relevant to psychiatrists.
Not surprisingly, they have not made much progress treating either
condition.
In the days
before the autism was so widely diagnosed, there were many more cases of childhood
schizophrenia reported, now it is very rarely diagnosed condition, it became autism.
I did look
for some statistics that included autism and schizophrenia, but those clever
psychiatrists seem to have separated them, so autism is with developmental
disabilities and schizophrenia is not.
But I did
find some interesting statistics about developmental disabilities.
When you
look at the US statistics (1997 – 2008), based on parent-reported developmental disabilities.
You can see that
about 15% of kids have some kind of developmental disability. Cases of autism increase from 0.2% to 0.7% over the ten years, but those with a learning
disability is pretty flat at around 7% and mental retardation (MR) / intellectual
disability is also pretty flat at 0.7%.
You also see
that the incidence of seizures remains flat at about 0.7%.
According to
the medical research, about 30% of people with autism will also have seizures;
you would expect to see a seizure “epidemic’, if there had been an autism
“epidemic”. Whereas diagnosing autism is
highly subjective, recognizing most types of seizure is not.
So clearly
the numbers do not add up. Perhaps now
only 10% of people with autism have seizures?
Or perhaps only 30% of people with autism, really have it?
The same is
true with the incidence of mental retardation (intellectual disability) it
remains flat at 0.7%. According to the
WHO, 50% of people with autism also have MR.
So, if there had been a big increase in new people with autism, you
would expect an increase in MR. If the
level of MR remains flat it would seem that some people with MR have just been
given an additional diagnosis of autism.
Either that, or the 50% figure is now much lower in the US, (which is
what I expect is the reality).
With even the
most basic figures not adding up, is it really surprising how little progress
has been made in the hard part – actually finding treatments?
Autism has
changed and now means entirely different things, to different people. In particular, comparisons across countries
are completely meaningless.
Schizophrenia
Schizophrenia
has also changed and is now considered as a family or spectrum of disorders.
Like autism,
nobody really knows what causes schizophrenia and most likely many things do,
like autism. There is no single gene,
like with Fragile-X or Retts, and there is no cure.
When researchers compared the mixture of genetic dysfunctions in schizophrenia and autism, they found a clear overlap. This
is interesting and perhaps should not have come as a surprise.
In some ways
Fragile-X and Retts are actually the opposite of autism. For example in the case of Retts, the very
important substance, Nerve Growth Factor (NGF), is almost at zero, whereas in autism
levels tend to be elevated.
Just as we
can learn from the comorbidities of autism, I think we can learn a thing or two
from the existing research in Schizophrenia.
Indeed I already have.
MR
If anyone
was seriously researching treating Mental Retardation (MR), in physically
“normal” people, who have not suffered from a brain infection, toxic exposure, malnutrition
or any kind of pre-natal or natal problem, we would have another great
resource. It would probably show that,
in some cases, MR is caused by a partially-reversible imbalance in the actions
of various neurotransmitters, ion channels, hormones etc. Some of these imbalances will also exist in
numerous cases of autism.
According to
the well-known expert, Professor Howlin, only about 20% of people with ASD have
an IQ in the normal range (i.e. above 70) and 50% have moderate or greater MR
(i.e. IQ less than 50). It would seem
that the missing 30% must have mild MR (i.e. an IQ 50 to 70).
I suspect
that the cognitive improvement found by treating some types of autism could be replicated
in some cases of MR, without ASD. If
there were any clever therapies for treating MR, I would think they would
likely be beneficial in autism. In most
countries, as many children have MR as have ASD, so it is strange nobody is
looking how to treat it. They assume the
“defects” are hard-wired into the brain; I looks to me that some are not.
Clinical Trials
Even though
ASD is a lifelong condition, nearly all the clinical trials are in children,
and most often, in quite young children.
Assessing such people is doubly difficult. Working with adults should be much easier and
provide better quality data.
Other
neurological conditions like schizophrenia and bi-polar disorder are regarded
as adult conditions, so hopefully the quality of the research data is
better. We will see.
Plenty of
adults have ASD and the ones with Asperger’s will have no difficulty articulating
the effects of any intervention, so it is a pity they are rarely involved in
research.
Conclusion
On a happier
note, I believe that if you can tune the autistic brain to its optimal
performance, you will see a marked improvement in cognitive ability and, by
implication, in measured IQ.
I have no
doubt that a well executed, intensive ABA program, over a few years, could also
show a marked improvement in measured IQ, in many cases.
ABA is also a kind of retuning of the brain, but it has to be done
right to be effective.
Biological tuning plus ABA should yield the best results.
Biological tuning plus ABA should yield the best results.
As for schizophrenia, the biological "overlap" with autism does indeed exist. Two such areas are dysfunctional calcium channels and indeed the glutamate receptor mGluR5. This will be developed later.
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