Archive for November, 2009

Infection, Allergies and Autism

Friday, November 27th, 2009

The possibility of intrauterine infections as a plausible explanation for the increased autism prevalence in children born to immigrant mothers is relevant. Hypothetically, mothers arriving from a totally different culture may not have been exposed to the same type of infections as have native mothers. This explanation would only hold if the mothers had lived in the immigrant country from at least the second trimester (the period during which infection by agents to which the mother is not immune would damage the brain in ways which would lead to autistic symptomatology). This applied in all three cases in the present study.  [pp. 143-4] (Gillberg, C., Schaumann, H. & Gillberg, I. C. (1995). Autism in immigrants: Children born in Sweden to mothers born in Uganda. Journal Of Intellectual Disability Research: JIDR, 39(Pt. 2), 141-4.)

Season of birth effects have the potential to make clearer the cause of autism in equatorial populations migrating to Northern climes. If those with autistic tend to be born in certain months, several etiologies are suggested.

One in the Vitamin D hypothesis. Another is the influence of the pineal gland on testosterone levels.

Related in the possibility that allergies are causing autism, allergies in a pregnant mother. How to allergies influence testosterone levels? Do the stress they cause increase testostesterone levels? Are children conceived at certain times more vulnerable to autism when mothers are highly allergic in the fall?

If maturation rates are set at a specific time in gestation, what influences testosterone levels at that time may be encouringing autism. How much effect does infection and allergies have upon uterine testosterone levels?


Autism and Immigration

Wednesday, November 25th, 2009

Lotter (1978) examined children attending services in nine major cities in sub-Saharan African countries. He found fewer children with autism than expected (as compared with prevalence rates in industrialized countries). However, as Lotter noted (and as highlighted by Wing 1993), it was not possible to carry out a proper prevalence investigation in the area concerned. Interestingly, there was a marked excess of children with autism who had parents who had lived abroad for any period of time (indicating a possible relationship between autism and migration).  [p. 143] (Gillberg, C., Schaumann, H. & Gillberg, I. C. (1995). Autism in immigrants: Children born in Sweden to mothers born in Uganda. Journal Of Intellectual Disability Research: JIDR, 39(Pt. 2), 141-4.)

Parents returning home had autistic children more often than those that never left. This begs several questions. Does this effect influence both moms and dads? Were the autistic children gestated overseas? What was the influence of latitude (was there more autism among parents that were coming back from extreme Northern or Southern climes)? If parents conceived and gestated children both locally and far away, what was the difference in autism?

Parents that immigrated to Northern and Southern locations, are there opposite season of birth effects?


Ugandan and Somali Autism

Tuesday, November 24th, 2009

Three boys diagnosed as suffering from autistic disorder were born in Sweden to mothers born in Uganda. Two were related but the third boy was unrelated to the others. The prevalence for autistic disorder in Göteborg children born to mothers who were born in Uganda was 15% which is almost 200 times higher than in the general population of children. The possible reason for the high autism rate in this particular ethnic subgroup is discussed. (Gillberg, C., Schaumann, H. & Gillberg, I. C. (1995). Autism in immigrants: Children born in Sweden to mothers born in Uganda. Journal Of Intellectual Disability Research: JIDR, 39(Pt. 2), 141-4.)

Somali and Ugandan autism rates skyrocket when children are born in Northern latitudes like Sweden and Minnesota. If light is having an impact, we would expect to see season of birth effects. Both the Vitamin D and testosterone/pineal theories, based upon light, should be revealing season of birth effects.

Another question would be, are mothers and fathers immigrating from equatorial regions to Northern climes having autistic children in larger numbers? What happens when couples with Indonesia immigrate to Scandinavia and Minnesota?


Autism, Vaccines and Neoteny

Monday, November 23rd, 2009

This study was prompted by findings reported to the Institute of Medicine by Blaxill in July 2001, which showed increases in autism incidence in California in association with increases in the use of thimerosal-containing vaccines during the 1990s. To further examine the plausibility of this finding, this study took advantage of the cessation of thimerosal use in Denmark and Sweden in 1992 to conduct a before and after comparison of the incidence or case numbers of autism. In both countries, autism increases throughout the years 1987-1999, contrary to the decrease in autism that would be expected after 1992 if thimerosal exposure was related to autism. The increasing trend for autism is most notable in Denmark where the number of autism cases rises substantially even after the discontinuation of thimerosal use. (Stehr-Green, P., Tull, P., Stellfeld, M., Mortenson, P. B. & Simpson, D. (2003). Autism and thimerosal-containing vaccines: Lack of consistent evidence for an association. American Journal of Preventative Medicine, 25(2), 101-6)

Vaccines are easily the most widely discussed controversial cause of autism. I assume autism has several causes, concentrating on those that influence rates of maturation. Vaccines haven’t seemed relevant to the particular focus my work addresses, evolutionary causes.

The excerpt above notes surges in autism in Denmark and Sweden. It hadn’t crossed my mind until now, but it makes sense that increases in autism would most likely occur in Northern climes (encouraged by the pineal/testosterone connection, light influencing testosterone levels based on seasonal effects) and in Scandinavia where the populution already exhibits neoteny in both sexes.

I would guess that Scandninavian autism would have larger percentages of males to females with autism, what with females displaying neoteny as opposed to acceleration.


Autism and Womb Dynamics

Friday, November 20th, 2009

Ploeger’s research reveals that in the period between 20 and 40 days after fertilisation, the embryo is highly susceptible to disruptions. In this period, early organogenesis, there is a lot of interaction between the different parts of the body. If something goes wrong with a given part of the body, it greatly influences the development of other parts of the body. As people with schizophrenia and autism frequently have physical abnormalities to body parts formed during early organogenesis, Ploeger concluded that the foundation for these psychiatric disorders is laid very early during pregnancy…The existence of a relationship between unhealthy behaviour during pregnancy and the subsequent development of schizophrenia and autism in the child was already known. However, Ploeger’s hypothesis that the early organogenesis stage is the most critical, is new. Ploeger bases her hypothesis on an extensive study of scientific literature in this area. She often had to make use of related studies; although a lot of research has been done into prenatal influences on the development of schizophrenia and autism, little is known about the influence that the period between 20 to 40 days after fertilisation has. (Ploeger, A. (2008). Autism and schizophrenia share common origin [PhD Thesis]. Retrieved on Dec. 17, 2008 from http://www.nwo.nl/nwohome.nsf/pages/NWOA_7LPL4Q_Eng)

Simon Baron-Cohen’s work concluding that a mother’s uterine testosterone levels may be influencing the chance of autism suggests the question of what point or points during gestation does a mother’s testosterone levels have an effect. If indeed a child’s maturation rates are influenced by a mother’s testosterone levels, when does that occur?

Perhaps the most frustrating experience I’ve had as someone exploring these issues is my having lost the citation that states that a child’s maturation rate is influenced by a mother’s testosterone levels at six weeks before birth. The conclusion may be related to children born premature. If born before six weeks, a child exhibits a number of derivations, some possibly related to maturation rate.

Knowing at what point maturation rates are established, if guided by mother’s testosterone levels, provides an opportunity to explore environmental influences impacting a mother’s testosteron levels.


Autism and Schizophrenia

Thursday, November 19th, 2009

Developmental psychologist Annemie Ploeger has investigated whether there is a connection between disorders in the first month of pregnancy and the development of schizophrenia and autism. Interestingly, many physical abnormalities of autistics are also prevalent in schizophrenics. For example, both autistics and schizophrenics sometimes have protruding ears and peculiar toes. There are also differences: a large head and intestinal problems, for example, are typical traits occurring in autistics. From this, Ploeger concluded that the two disorders share a common origin. The same error that occurs very early in pregnancy develops into autism in one individual and schizophrenia in another. (Ploeger, A. (2008). Autism and schizophrenia share common origin [PhD Thesis]. Retrieved on Dec. 17, 2008 from http://www.nwo.nl/nwohome.nsf/pages/NWOA_7LPL4Q_Eng)

Bernard Crespi’s Psychosis and Autism as Diametrical Disorders of the Social Brain also finds patterns that bridge schizophrenia and autism. Yet schizophrenia seems to display more than one lateraterlization convention and varying corpus callusum widths and lengths depending on the study being explored.

I suspect the schizophrenia, like autism has more than one etiology. Some forms may be closely related to autism as an evolutionary condition. Other forms perhaps early brain trauma related. Schizophrenia timing onset can be related to pubertal timing and differs between the sexes. This feels like a major clue as regards connections to testosterone and estrogen levels.


Autism Causes and Birth Order

Wednesday, November 18th, 2009

Cocaine in all forms is the number one illicit drug of choice among pregnant women. Records of 70 children with cocaine exposure in utero who were referred for developmental evaluation at a large inner-city hospital were reviewed in an effort to determine whether a specific pattern of abnormalities could be discerned. Patients received physical examinations, neurological screenings, and behavioral and developmental assessments based on the Gesell Developmental Inventory, and the Denver Developmental Screening Test. Documentation of specified drug use was obtained by history. Mean age (SEM) at referral was 19.2 (1.7) months. All mothers used cocaine in one of its forms, although polydrug use was common. Growth parameters were low (median = 15th percentile). Significant neurodevelopmental abnormalities were observed, including language delay in 94% of the children and an extremely high frequency of autism (11.4%). The high rate of autistic disorders not known to occur in children exposed to alcohol or opiates alone suggests specific cocaine effects. (Davis, E., Fennoy, I., Laraque, D., Kanem, N., Brown, G. & Mitchell, J. (1992). Autism and developmental abnormalities in children with perinatal cocaine exposure. Journal of the National Medical Association, 84(4), 315-19).)

A recent study noted that both first born and late born children exhibited greater tendencies toward autism than children in the middle. As a woman grows older her testosterone levels increase. This might explain more autistic children coming to older mothers. Why are firstborn often autistic?

One reason may be that this is the most difficult of births, and often pregnancies. Autism, besides being a condition with genetic causes, is caused by such effects as mother’s use of cocaine. It could be explored whether autistic children of older mothers vs. firstborns come from families of left handers, or families displaying OCD, borderlines, or narcissists an equal amount of the time. (Those conditions are associated with autism in family of origin.)

Also, how often do mothers giving birth to an autistic child as their first child choose to have no other children? This would skew the statistics.


Autism, Testosterone and Estrogen

Tuesday, November 17th, 2009

“…When the children were followed-up after birth, those children with higher levels of foetal testosterone had lower rates of eye contact and were slower to develop language, as toddlers.  In primary school they had more social difficulties and reduced empathy, and they also had stronger interests in systemizing…These studies looked at individual differences in otherwise typically developing children.  We cannot yet conclude that elevated rates of foetal testosterone cause autism or Asperger syndrome, as the children in these studies do not have a diagnosis.  It is of interest that using the Child AQ (Autism Spectrum Quotient)…completed by the mother, those children with higher levels of foetal testosterone also had a higher score on the AQ (more autistic traits).  But the test of the foetal androgen theory will come when large enough samples of amniotic fluid are available, with follow-up data relating to actual diagnosis.” [p. 95] (Baron-Cohen, S. (2008). Autism and Asperger syndrome: The facts. New York: Oxford University Press.)

Geschwind and Galaburda (1987) hypothesized that testosterone influenced cerebral lateralization, handedness and a number of diseases and conditions including autism. Baron-Cohen and colleagues have discovered what seems like direct connections between a mother’s testosterone levels and autism and Aspergers. A question is, is estrogen influential in this mix?

If estrogen levels impact the timing of puberty, influening testosterone surges, does estrogen impact the timing of infant synapse pruning that comes from testosterone surges. That pruning may have a lot to do with handedness and cerebral lateralization. Lateralization seems related to autism with 20% of children with autism displaying brains at the 95 percentile with right hemispheres that seemed not to have ever been pruned by testosterone surges.


Autism Percentages

Monday, November 16th, 2009

“…The striking ratio of males to females among individuals with the condition [autism].  The sex ratio of males to females reported in the literature ranges from approximately 2:1 to 4:1 (Lord and Schopler 1987; Wing 1981), and approximately 9 times as many males as females are diagnosed with Asperger’s syndrome (which can be viewed as a milder form of autism).” [p. 39] Baron-Cohen, S. (2008). Autism and Asperger syndrome: The facts. New York: Oxford University Press.

If there a larger number of females to males in Aspergers than there are in autism, the percentage of males with ASD will increase with an increase in the number of children diagnosed. Unless the evaluation protocol is revised which is now being considered. If Aspergers is separated from autism as a diagnosed condition the numbers will likely become more difficult to parse.

I believe that autism is an evolutionary condition influenced by changes in social structure. I hypothesize that females evolved sooner than males to achieve split consciousness evidenced by cerebral lateralization. When social structure and environmental forces compel the emerence of evolutionary forebear features, we have to go further back to find woman challenged in the same way that men are when wrestling with the transition to the new brain of the split conscious human being.

Current ratios reflect evolutionary pathways.


Autism, Testosterone and Estrogen?

Friday, November 13th, 2009

Testosterone promotes male-typical neural and behavioral development in non-human mammals. There is growing evidence that testosterone exerts similar influences on human development, although the range of behaviors affected is not completely known. This study examined the hypothesis that autistic traits are increased following prenatal exposure to abnormally high levels of testosterone caused by congenital adrenal hyperplasia (CAH). Sixty individuals with CAH (34 female, 26 male) and 49 unaffected relatives (24 female, 25 male) completed the Autism Spectrum Quotient (AQ). Females with CAH scored significantly higher than unaffected females on total AQ score, largely due to enhanced scores on subscales measuring social skills and imagination. These results suggest that prenatal exposure to high levels of testosterone influences some autistic traits and that hormonal factors may be involved in vulnerability to autism. (Knickmeyer, R., Baron-Cohen, S., Fane, B. A., Wheelwright, S., Mathews, G. A., Conway, G. S., Brook, C. G. & Hines, M. (2006). Androgens and autistic traits: A study of individuals with congenital adrenal hyperplasia. Hormones and Behavior, 50(1), 148-53.)

I’m not finding much in the way of reference to estrogen and causes of autism. When Geschwind and Galaburda opened up discussion in the direction of testosterone in the 1980’s, it was in the context of testosterone influencing cerebral lateralization, or what I would describe as the rate of maturation. Other the Tim Crow, no academic was citing the heterochronists or those that specialize in the rate and timing of maturation as regards cerebral lateralization.

Estrogen does not enter the discussion because estrogen is not normally associated with the timing of maturation. If estrogen influences timing, then autism may be influenced by estrogen levels if degrees of cerebral lateralization are influenced by estrogen and degrees of cerebral lateralization is related to autism.


Autism, Melatonin, the Pineal, Testosterone and MN Somalis

Thursday, November 12th, 2009

Melatonin is produced in the dark by the pineal gland and is a key regulator of circadian and seasonal rhythms. A low melatonin level has been reported in individuals with autism spectrum disorders (ASD), but the underlying cause of this deficit was unknown. The ASMT gene, encoding the last enzyme of melatonin synthesis, is located on the pseudo-autosomal region 1 of the sex chromosomes, deleted in several individuals with ASD. In this study, we sequenced all ASMT exons and promoters in individuals with ASD (n=250) and compared the allelic frequencies with controls (n=255). Non-conservative variations of ASMT were identified, including a splicing mutation present in two families with ASD, but not in controls. Two polymorphisms located in the promoter (rs4446909 and rs5989681) were more frequent in ASD compared to controls (P=0.0006) and were associated with a dramatic decrease in ASMT transcripts in blood cell lines (P=2 x 10(-10)). Biochemical analyses performed on blood platelets and/or cultured cells revealed a highly significant decrease in ASMT activity (P=2 x 10(-12)) and melatonin level (P=3 x 10(-11)) in individuals with ASD. These results indicate that a low melatonin level, caused by a primary deficit in ASMT activity, is a risk factor for ASD. They also support ASMT as a susceptibility gene for ASD and highlight the crucial role of melatonin in human cognition and behavior. Melke, J., Goubran Botros, H., Chaste, P., Betancur, C., Nygren, G., Anckarsater, H., Rastam, M., Stahlberg, O., Gillberf, I. C., Delorme, R., Chabane, N., Mouren-Simeoni, M. C., Fauchereau, F., Durand, C. M., Chevalier, F., Drouot, X., Collet, C., Launay, J. M., Leboyer, M., Gillberg, C. & Bourgeron, T. (2008). Abnormal melatonin synthesis in autism spectrum disorders. Molecular Psychiatry, 13(1), 90-8.

I occasionally write of the Geschwind and Galaburda inspired conjectures that autism is influenced by fluctuating mother uterine testosterone levels in connection to populations immigrating from equatorial regions to Northern climates. Pineal gland responses to light impact testosterone levels to behave as if an individual is still in Africa experiencing diurnal light cycles of 30% fluctuations, excepts changes ebb and flow seasonally, not daily. This could explain Minnesota Somali autism.

Melatonin is part of this equation, acting as intermediary between the pineal gland and fluctuating hormone levels. When the autistic show deficits in melatonin, consider the possibility that this is directly connected to the effects of light.

What might be the melatonin levels of the Somali autistic and their siblings?


Writing and Drawing

Wednesday, November 11th, 2009

Researchers at the Johns Hopkins School of Medicine in Baltimore have been exploring handwriting and children with autism and Aspergers. They discovered their handwriting was poorer than that of children without the condition.

I maintain two different ways of writing that exhibit two dramatically different results. I can write as I subvocalize, letting the words pour out my fingers. The result is almost unintellible. I often can not read my own writing. Or, I can draw my words. When I draw my words I am making pictures that represent the letters that have meaning. When I draw my words they are not only readable but notably attractive.

Having had several Aspergers aspects to my personality when I was young, I was often considered one of the two best artists in my class, worst speller, and worst penmanship. Buddy Whit Watts, was also a good artist and bad speller. There is a pattern here.

I think it has to do with being good at symbol but not at sign. As beings still mostly familiar with primary process (one time, one place, no opposites) the autistic can experience one thing representing another in a fashion that the two are the same, but they are not good at split consciousness where one thing is associated with other things, but they are not the same.

Writing is not drawing. Understanding the difference suggests an understanding of the different consciousnesses associated with the two.


Schizophrenia and Autism

Monday, November 9th, 2009

To limit genetic heterogeneity, this study focused on the widely extended pedigrees of Ashkenazi Jewish schizophrenic and autistic probands, to determine if similar causal mechanisms might obtain for both conditions. At least two previous epidemiological studies have demonstrated increased risk for schizophrenia in Ashkenazi Jews. The hypothesis posed is that increased prevalence of various rare autosomal recessive diseases among the Ashkenazim might contribute to the increased vulnerability to schizophrenia and to autism in this large genetic isolate. Rates of amyotrophic lateral sclerosis (ALS) and bleeding disorders were significantly increased among relatives of schizophrenic and autistic probands, compared to relatives of normal probands. These results suggest new candidate loci in schizophrenia and autism, particularly the chromosome 15q23-24 locus of the hexosaminidase A gene, causing various GM2 gangliosidoses, and the 21q22.1-q22.2 loci of the antioxidant, superoxide dismutase gene, and a cytokine receptor gene. (Goodman, A. B. (1994). A family history study of schizophrenia spectrum disorders suggests new candidate genes in schizophrenia and autism. The Psychiatric Quarterly, 65(4), 287-97.)

A number of studies have suggested a relationship between schizophrenia and autism, perhaps most recently Psychosis and Autism as Diametrical Disorders of the Social Brain by Bernard Crespi. It seems that schizophrenics and autistics often share family of origin, even though the brain structure and behaviors are not alike. If autistics often come with the first born and latest children of a mother, do schizophrenics have a similar birth order pattern?


Autism as an Evolutionary Condition

Sunday, November 8th, 2009

Some extreme variants are associated with the deviations of psychological function that we describe as psychosis. These states are seen as boundaries of the distribution of personality variation, including the capacity for language and emotional expression. In particular, those with the earliest manifestations (i.e. schizophrenia, Asperger’s syndrome and autism) have the greatest impairments of communication and social ability, and also demonstrate a failure to develop anatomical asymmetry. In summary, key features of the theory are that the psychoses are disorders of specifically human evolution, arising from variation in the genes controlling hemispheric asymmetry that has led, by the mechanism of sexual selection, through progressive delay in maturation (neoteny) to increased brain size and intelligence. The most readily testable prediction is that the gene for asymmetry (and by implication contributing to predispostion to psychosis) should be X-Y homologous (p. 24). Crow, T. J. (1995). A Darwinian approach to the origins of psychosis. British Journal of Psychiatry, 167(1), 12-25.

Professor Tim Crow’s work offers a powerful evolutionary explanation for autism by concentrating on neoteny’s connection to cerebral symmetry. Crow mostly works on schizophrenia. His works seems relatively little cited when it comes to autism. Combining Crow’s insights regarding neoteny with Geschwind and Galaburda’s understanding of the influence of testosterone on cerebral lateralization with Annett’s discovery of random handedness relationship with lateralization, the foundation for an evolutionary understanding of autism is evident in the neuropsychological literature.


Fragile X and Testicle Size

Thursday, November 5th, 2009

A piece appeared today describing new clinical trials.

CAMBRIDGE, Mass., Nov. 5 (UPI) — U.S. scientists say they are starting a trial of a medication designed to treat the neurochemical defect underlying Fragile X syndrome.

I’ve wondered about how suggestive Fragile X features are of the origin of autism. In 1998, I predicted that a language challenged group of individuals should feature larger brains. I discovered a large percentage of autistics do. Later I estimated that autistic males, if indeed they represent an ancient matrifocal protype, should have larger testicles. (Primates matrifocal promiscious social structures reveal males with large testes.)

I could find no evidence that studies had been conducted on autistic males to determine testicle size, except for Fragile X. Fragile X males display unusually large genitals.

I have no idea how this would relate to the medication intervention in clinical trials. Perhaps there is an gonadal hormone system component.


Autism and Downs

Wednesday, November 4th, 2009

Family history data on 99 autistic and 36 Down’s syndrome probands are reported. They confirmed a raised familial loading for both autism and more broadly defined pervasive developmental disorders in siblings (2.9% and 2.9%, respectively, vs 0% in the Down’s group) and also evidence for the familial aggregation of a lesser variant of autism, comprising more subtle communication/social impairments or stereotypic behaviours, but not mental retardation alone. Between 12.4 and 20.4% of the autism siblings and 1.6% and 3.2% of the Down’s siblings exhibited this lesser variant, depending on the stringency of its definition. Amongst autistic probands with speech, various features of their disorder (increased number of autistic symptoms; reduced verbal and performance ability) as well as a history of obstetric complications, indexed an elevation in familial loading. No such association was seen in the probands without speech, even though familial loading for the lesser variant in this subgroup, was significantly higher than in the Down’s controls. The findings suggest that the autism phenotype extends beyond autism as traditionally diagnosed; that aetiology involves several genes; that autism is genetically heterogeneous; and that obstetric abnormalities in autistic subjects may derive from abnormality in the foetus. Bolton, P., MacDonald, H., Pickles, A., Rios, P., Goode, S., Crowson, M., Bailey, A. & Rutter, M. (1994). A case-control family history study of autism. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 35(5), 977-900.

Downs Syndrome exhibits powerful suggestions of neoteny with some studies calling attention to the correlations. I’ve hypotheized and discussed in detail the influence of neoteny on autism. Downs is a chromosonal condition. Autism is far more subtle. Do any of the my hypothetical causes of autism also apply to Downs? For example, are there higher rates of Downs among Minnesota Somalis?


Gay and Lesbian Patterns

Tuesday, November 3rd, 2009

The raised incidences of strong left-handedness and of mixed-handedness in homosexual men, as in dyslexics, are mutually consistent under the normal distribution function, as expected by the right shift theory of handedness. It is argued that atypical laterality in these groups is better described as a “reduction of right shift” than as a “left shift”. Annett, M. (1988). Comments on Lindesay: Laterality shift in homosexual men. Neuropsychologia, 26(2), 341-3.

Surveying several studies on gay and lesbian neurological and endocrine system features I am struck by the male maturational delay, female maturational acceleration paradigm. This is what I hypothesize for autism and Aspergers.

McCormick and Witelson (1991) noted specific neurological differences between heterosexuals and homosexuals with McCormick, Witelson and Kingston (1990) observing greater numbers of lefthanders among both lesbians and gays. Stress increases testosterone levels in woman. Dorner, Schenk, Schmiedel, and Ahrens (1983) observed that increased stress in a pregnant woman increases the chance of a homosexual son. Annett (1988) notes the higher percentages of left handedness among gays, compared that to dyslexics and suggested that this increased the likelihood of anomalous dominance or two cerebral hemispheres the same size.

Understanding autism involves exploring similar patterns in other conditions exhibiting maturational delay and acceleration.


Lefthandedness

Monday, November 2nd, 2009

Blogs and news stories often note the recent study that concluded that autism rates are dramatically increasing. One in sixty males are now estimated to have autism or Aspergers.

An issue that keeps coming to mind is whether left lefthandedness or ambidexterity is on the rise. This would be a dramatic indicator of the cause of autism. There have been no resent such studies that I am aware of. Left handedness and ambidextrousness or both indicators of “random handedness” or those without a genetic predisposition toward right handedness, people with right cerebral hemispheres that did not experience the degree of cerebral synapse pruning that normal right handers did. These are people with bigger brains. The autistic often have bigger brains.

If autism is on the rise and random handedness is increasing that means maturational delay is increasing. This would be useful information.


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