“Schizophrenia’s Unyielding Mysteries” is the title of an article published in the May 2107 issue of Scientific American magazine. Quotations in this blog post are from that article unless otherwise specified.
Schizophrenia and Autism: Similarities and Differences
I’m interested in schizophrenia because it is so closely associated with autism. At one time, autism was labeled “childhood schizophrenia” because {1} autism was (mistakenly) thought to appear only in children, and {2} it was generally held (mostly correctly) that schizophrenia appeared only during adolescence or later in life. The general view these days is that the two are different neurological conditions that share many outward signs (at least in the early stages of schizophrenia), and in some individuals may overlap (i.e. both may be present).
Until the 1970s, many clinicians used ‘autism’ and ‘childhood-onset schizophrenia’ interchangeably. Today these conditions are recognized as separate, but there are similarities. For instance, the social difficulties present in autism can resemble the social withdrawal seen in schizophrenia.
[from an online article “Do Schizophrenia and Autism Share the Same Root?“]
Current terminology identifies a condition (completely distinct from autism) known as childhood schizophrenia, said to be “an uncommon but severe mental disorder in which children interpret reality abnormally.”
Hans Asperger was aware of the potential confusion, and took care to distinguish between autism and schizophrenia, pointing out that autism is a stable personality type, whereas schizophrenia is a degenerative condition. Leo Kanner, from what I can gather, did not share this view, believing that autism in children was, in fact, the precursor of schizophrenia. Current thinking supports Asperger’s viewpoint.
Both Kanner and Asperger referred to Eugen Bleuler’s concept of autism with the former considering infantile autism as a form of early schizophrenia and the latter as a form of psychopathic personality. Interestingly, Bleuler considered autism not only as a core symptom of schizophrenia but also as a dimension spanning across a wide range of non-schizophrenic conditions including superstition and pseudoscience. Similarly, Asperger seemed to suggest a spectrum perspective while pointing out that the capacity to withdraw into an inner world of one’s own special interests is available in a greater or lesser measure to all human beings. Moreover, he emphasized that this ability has to be present to a marked extent in those who are creative artists or scientists.
[taken from the article “From Asperger’s Autistischen Psychopathen to DSM-5 Autism Spectrum Disorder and Beyond: A Subthreshold Autism Spectrum Model” — this article also points out the problems of overlapping diagnostic criteria, among other key observations]
The prevalence of autism is generally given these days at around 2% of the population, although some studies have estimated it to be as high as 4%. I have seen numbers for schizophrenia at around 1%. I suspect all of these estimates are on the low side, because of increasing awareness of and the broadening of diagnostic criteria, particularly with regard to autism.
Genetic or Environmental?
The SciAm article’s subtitle begins “Gene studies were supposed to reveal the disorder’s root. That didn’t happen.” The same thing could have been written about autism. Millions of research dollars have been spent in recent years looking for “autism genes” — in the same manner, researchers hoped to find simple explanations for schizophrenia as well as for many other so-called “disorders.” Neurology, it turns out, is a lot more complicated than that, and the chimera refused to be found.
Since the advent of large-scale genetic studies just more than a decade ago … studies have yet to deliver [new insights] for schizophrenia, as well as depression and obsessive-compulsive and bipolar [behaviors].
Similarly, searches for neurological characterizations of sex/gender differences have found that people are better described as having a “mosaic” of characteristics rather than lying on a “spectrum” (continuum) of them. In other words, there is no simple on/off switch that makes a person autistic or female or schizophrenic or any number of other categorizations.
A big part of the problem here is that there are no objective tests that will identify the label being studied. If there were commonly-accepted brain scans, say, or blood tests or DNA markers that could identify autism or schizophrenia, we would be using them as diagnostic tools. Instead, we find ourselves using subjective diagnoses to see if we can find associated biomarkers.
In the US, clinicians rely on the APA’s DSM; elsewhere they often use the WHO’s ICD.
In the criteria set out in both volumes, patients can have markedly different symptoms, … and still be diagnosed with a case of schizophrenia.
In any DNA study, a control group is compared with another group of people who have been identified with the condition for which the study is trying to find commonalities. Yet, if that study group is itself heterogeneous, united only by a common (and possibly flawed) set of diagnoses, it is not clear what will (or can) be learned about their common biology.
Another issue that is raised in this article is that of environmental influences. Although schizophrenia (like autism and many other similar conditions) are commonly thought to be highly “heritable” it is clear that lineage alone is not a reliable predictor, as shown by twin studies and other family comparisons.
In the early days of DNA decoding (i.e. more than 10 years ago), almost exclusive attention was given to the protein-coding portion of the human genome. The other 99% of genes were dubbed “junk DNA” — a characterization which struck me as ludicrous, since the logic of evolution would not tolerate Mother Nature passing along a bunch of energy-absorbing material that had no function. It is now understood that this “junk” contains (among other things) the instructions needed for when and where to build which kinds of proteins.
Very little is understood about what triggers the body to build the variants it chooses from among the enormous set of possibilities. Even identical twins, who, by definition, share nearly identical DNA, can develop very differently.
… when one member of a pair of identical twins is diagnosed with schizophrenia, the other twin is affected … only about half of the time…
Why is this? The jury is still out, of course, and we don’t know how much variability to attribute to external environmental influences versus random genetic variation. In any case, it appears (as with autism) that it will be impossible to find a direct link between a person’s genetic inheritance and the chances of developing the condition.
Are Interventions Possible?
What implication does all of this have for potential therapies? The grand hope of early DNA studies was that a small number of genes (perhaps even one) could be identified as “causing” schizophrenia. This would open up the possibility of developing drugs or other biological treatments that could alter the condition. Although some scientists continue this search, it is obvious that potential results are a long way off, and the current state of our understanding does not provide the key to developing such interventions.
A number of recent clinical trials, meanwhile, suggest that psychosocial therapies, especially CBT [cognitive-behavioral therapy] can help lessen both symptoms and suffering in schizophrenia patients.
I don’t know enough about schizophrenia to know whether schizophrenics “suffer” from their condition. That word is all too often used in connection with autism and other disabilities. In many cases, those of us who are disabled suffer not from our disability but from the mistreatment and misunderstanding that we receive from the world at large.
Parallels With Autism
The similarities will be quite obvious to those who have been following the course of autism research over the past few years. Far too much attention and money have been spent on genetic research, and far too little on alternatives. Interventions such as CBT and life-skills coaching have been proven to be effective, but precious little effort has gone into investigating which of these (or other) techniques are most useful, and how they are most effectively employed.
I’m a big believer in basic research. In fact, I’ve participated in many brain studies and have donated my DNA for analysis. I hope that research into genetics, as well as new brain imaging and other techniques, will result in a better understanding of what are the essential differences between the autistic brain and the neurotypical brain.
Yet, based on personal experience, I know that the most effective therapies are those that involve behavior modification. These include CBT, talk therapies, meditation and other mindfulness techniques, support groups, life-coaching, and many other variations. We know how to do these things; we need to learn how to do them better.
For those of us who are autistic, a greater understanding of autism will help smooth our path. Self-knowledge can lead us to be more comfortable in our differences, and also to a better understanding of how to communicate with those who don’t inhabit our dimension. A wider public understanding will, we can hope, lead to more acceptance.
Being autistic is different. Not better. Not Worse. Different. Understanding and Acceptance of this difference by all will help us unleash our potential. Diversity is a good thing. The world will be a better place.
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