© Mike Connor 2006.
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These notes begin with further thoughts concerning the extreme male brain hypothesis and the possible implications for an understanding of aetiologies.
The next section describes the
outcome of a survey comparing progress of children with ASD placed in
mainstream and specialist schools, with the result that the school placement
does not appear to be the critical factor in determining social or scholastic
progress; rather parental coping strategies plus child access to additional
facilities such as speech and language therapy are significant.
The final section continues the
themes of the non-association between vaccines and the aetiology of SD and
other conditions; and the possible value of psycho-stimulant medication for
children with ASD and ADHD albeit with caution required in the light of
adverse side effects and the limiting of benefits to a sub-sample of this
population.
M.J.Connor January 2006
The Extreme Male Brain Hypothesis
The work of Simon Baron-Cohen has included the exploration of the proposition that individuals with autism have an imbalance in two cognitive capacities or styles with the net effect of evoking behaviour which is significantly more characteristic of males than of females.
In an interview (reported by
White 2005) Baron-Cohen differentiates systemisers from empathisers. Males are seen as having a stronger drive
towards systemising while females have a stronger drive to empathise, and, in
attempts to understand autistic behaviour, it has been noted that individuals
on the autistic spectrum show an exaggeration of this male style. There are more systemisers in this
population.
Systemising is a matter of trying
to understand the workings of some mechanical or natural or abstract system, be
it a machine or a part of the body or some mathematical construct.
Empathising is about being able
to imagine what someone else is thinking or feeling and having an (appropriate)
emotional response to that other person’s mental state.
Empathising is perceived as being
more than simply a well developed Theory of Mind in that there are these two
components …. not just being able to see another person’s point of view or to
recognise his or her feelings, but also having the necessary facility to make a
suitable response. This latter, above
and beyond the perception of the other person’s mental state, is the
significant part of empathising and what distinguishes it from Theory of Mind
capacities per se.
Baron-Cohen goes on to describe
how the two capacities were assumed initially to be independent, but longer
term observations have indicated a relationship in that individuals in the
population at large who are strong in one area tend to be weak in the
other. There is a small but consistent
negative correlation, with the possible implication of dependence on a shared
mechanism such as some genetic or hormonal influence.
The capacity for empathising is
highlighted by assessments which involve the identification of emotions from
photographs of faces, and evidence indicates that individuals with autism find
this difficult. This pattern relates to sex differences in the general
population in that women are more successful than men in this kind of task.
An alternative assessment
involves asking someone to listen to a passage of speech and to detect if it
contains some hurtful element. The same
patterns of findings emerges in that autistic compared to non-autistic
participants, and boys/men compared to girls/women, consistently do more poorly
in such a task.
On the other hand, any test that
involves systemising tends to produce the better scores among children and
adults with autistic spectrum disorder.
Further, Baron-Cohen refers to
children with more severe levels of autism (those with little language and
scoring low on cognitive measures) as having strong obsessional behaviours and
a tendency to act in a repetitive way which could be interpreted as a form of
systemising … a pre-occupation with establishing or maintaining a specific and
local “system”.
With regard to (measured)
ability, there is a developing view that the frequency of finding low levels of
general cognitive functioning may be, in some cases at least, an artefact of
this systemising-empathising dichotomy.
The stronger the trend towards
systemising, the narrower the attention to the environment as a whole; or the
drive to focus upon one activity and to repeat it over and over replaces the opportunity
to become familiar with other elements of the surroundings, be they objects,
ideas, or people. The net effect would
be to depress cognitive scores and identify the child as having learning
difficulties.
With regard to “pathways”,
Baron-Cohen discusses the concept of “
assortative mating ” which describes how two individuals are more likely to be
mutually attracted and to form a relationship, perhaps leading to long-term
commitment and to raising a family, if they share characteristics.
Individuals tend to choose
partners who are seen as similar to themselves, with the possible implication
that systemising and empathising are two of the observable characteristics that
guide the choice. If the two members of a couple are strong on systemising, they
are more likely to produce children with such a style which, in some cases, is
associated with an autistic spectrum disorder.
Evidence cited in support of this
supposition emerges, firstly, from a trend in findings from the Embedded
Figures Test that both the parents of children with ASD show good attention to
detail; and, secondly, that they both show more-than-chance probability of
having fathers whose work is within an area requiring good systemising
skills …. ie good systemising appears commonly to run in both sides of these
families, indicative of assortative mating.
(The example is given of Silicon Valley in California where so many
people work in the (strongly systemising) computer science industry and where
there has been an increase in the incidence of children diagnosed with ASD
above the nationally-typical rate …. although it is stressed that the data
remain anecdotal and not subject to formal investigation).
This is all further evidence of
the strong genetic influences, even if there is a long way to go in identifying
which genes are the significant ones and precisely which functions they
control.
A related area of study, the
significance of foetal testosterone exposure, has offered some further support
for this male brain hypothesis in that the higher the level of foetal
testosterone (as assessed via an analysis of amniotic fluid) the less eye
contact made by the child at age 12 months and the slower to develop language
skills.
Following up the same children at
age 4 years has shown a link between the foetal testosterone level and the
greater level of social difficulty and the narrower range of interests. The possible implication is that the
heightened focus upon this small range of interests … the systemising style … inhibits social interaction for which a
more empathising style would provide a firmer basis.
One area of speculation is the
precise role of the X chromosome and the difference in influence according to
whether it is inherited from the father or mother. The X chromosome does have a role in the regulation of
testosterone, thus indicating a possible link between genetic and hormonal
action.
In sum, the “extreme male brain”
could be the end point of a number of pathways, with a need for further studies
involving larger samples and the opportunity to make and test predictions about
behaviours and capacities.
As a “stop press“ addendum to the
above, one notes the item (Baron-Cohen 2006) in which he responds to a
suggestion, emerging from a presentation at the British Association Fair (David Skuse, October 2005), to the effect
that the theory of extreme male behaviour is not supported by available
data.
Instead, it was argued that, in
typically developing individuals, girls were better than boys at identifying
emotions during childhood and early adolescence, but this advantage was no
longer evident by late adolescence; and there seemed no sex differences at any
stage in respect of remembering faces or detecting eye contact.
Baron-Cohen’s response included
the suggestion that one has still got to explain this better
emotion-recognition skill among girls, detectable as early as 6 years of age,
and that the pattern is in line with his empathising-systemising view of gender
difference.
He goes on to argue that one can
cite a range of studies to indicate that this female advantage in recognising
emotions does persist into adulthood; and that differences between
outcomes of his studies and those of Skuse may be an artefact of the precise
methods and assessment instruments used.
For example, differences at later ages may have been obscured by ceiling
effects within the tests; and the detection of differences requires a test that
is sufficiently challenging to give rise to a range of scores.
Baron-Cohen also refers
anecdotally to the experience of producing a CD-Rom to illustrate the wide
range of human emotions during which there was much more difficulty in
identifying male actors than female actors with the capacity convincingly to
register complex emotional expressions. It may be, it is suggested, that sex
differences include demonstrating emotions through facial expressions as
well as reading them.
His final point is that a
capacity to recognise faces or to detect eye contact may be as much to do with
memory or being able to calculate the direction of gaze as much as any skill in
empathising.
The work by Waddington and Reed
(2005) was stimulated by the current emphasis upon mainstream inclusion for
children with SENs with its implication that “included” children will enjoy a
better quality of life, and achieve better social and educational performance
levels.
They point out that, despite this
being a critical area for the development of policy and practice, there is very
little research data available dealing with the inclusion of children with ASD;
and, it might be argued, the policy of inclusion for these children has
preceded the gathering of evidence whether it is actually better for their
success.
Their own archive study
investigated whether children in mainstream placements show enhanced
performance relative to those children in specialist placements.
In their introduction, the
authors note that “inclusion” or “integration” can mean many things and may
apply to children who are in full time attendance at a mainstream school or to
those who spend only some limited time in the mainstream setting to pursue
particular activities. This variation
is seen as a major inhibitor to making sense of existing studies which have
investigated the effects of inclusion or which have compared integrated with
segregated provision (with studies frequently failing to define what is meant
by inclusion or integration).
However, in their review of
existing evidence, they find equivocal results in that, for example, one
identified study failed to find language differences either in general level or
in rate of progress between children in segregated and integrated provision.
Another identified study
indicated that young children appeared to gain greater benefits socially from
integrated placements, although a further set of findings indicated that this
was a function of the presence or absence of the non-ASD peers. Teachers were
observed to interact less with the ASD children when their peers were
present. The target children were also
observed to initiate very few interactions in either setting, and it was
concluded that physical integration per se was not sufficient to bring about
social contact between the children with ASD and peers.
The extent of existing literature
was acknowledged to be limited and what evidence existed was seen as
inconclusive about whether or not inclusive settings benefit the child. The ideal of inclusion, therefore, cannot be
said to have evidence-based foundations.
Their own study involved
“secondary data”, ie information already collected by other investigators often
in natural settings and for a range of reasons. The sources of data for analysis were the LEA archive files about
children in their schools from which some elements could offer insight into the
performance of children in integrated settings and into the factors associated
with positive outcomes.
The sample of children targeted
in this current study comprised 73 boys and 11 girls from three boroughs in the
South-East of England. Criteria for
inclusion was that they had a diagnosis of ASD and left school no more than 5
years ago.
Measures were gathered about two
areas … the child outcomes in terms of national curriculum levels and school
placement, and about the interventions that had been made available, such as
the amount of speech therapy time and previous access to Portage sessions.
In addition, parental
questionnaires were completed in respect of diagnosis, parenting stress, and
developmental/medical history.
The findings showed that, in line
with expectation/policy, the children with ASD were more likely to be in
mainstream settings.
The severity of the autism
appeared not to be a factor in placements, nor the particular characteristics
or profiles of the children, with the apparent implication that placement was
not linked to precise levels or type of need, but a function of a combination
of some other factors such as the level of resources, or governmental policies.
Those children placed in units
attached to mainstream schools were receiving more speech therapy than those
placed in specialist or mainstream schools, although here was no difference in
the number of hours of SLT available to the different settings.
With regard to academic outcomes,
no significant differences were found, indicative of a lack of direct impact
upon achievement from mainstream schooling.
Significant correlations were
found between certain predictive and outcome measures. For example, social skill group attendance
was linked with improved literacy scores
(reading and spelling) suggesting
that social skill training may lead to generally improved language skills in
children with ASD.
Meanwhile, whether or not the
children had been involved in Portage facilities did not influence placement in
that those children with a history of Portage and those with no such history
were placed equally frequently in mainstream and specialist settings … although
the numbers were such as to keep conclusions tentative.
Parental coping abilities were
correlated positively with better results in writing and science. Their access to social and spiritual support
was related to better child outcomes in maths, reading, writing, and science;
and the willingness of the family to acquire and accept help was linked to
better outcomes in English, writing, and science.
In their conclusion, the authors
repeat that there is no indication that children in mainstream schools are more
successful than those in specialist provision, but acknowledge limitations in
terms of the gaps in the data and inconsistencies in the archive files.
The implication is that, if one
is to be able to cite truly evidence-based planning, there needs to be access
to more data such as fuller NC results, and reports plus assessment data from
educational psychologists.
With the addition of
questionnaire information, it was possible to highlight how school placement is
not the major variable in achievement, but that interventions such as social
skill sessions and the maintenance of full attendance are more significant.
Parental factors also play a big
part in determining child outcomes in that, for example, the child’s grades
will be the poorer as the parental level of stress increases.
The implication here is to identify
the level of support that parents need if they are effectively to manage the
child with ASD and manage their own potential stress, and to combine LEA and
Health Authority resources in identifying and meeting this need.
One might have thought that there is sufficient reassurance that vaccines (or the mercury-based preservative in vaccines) are not linked in any causal way with ASD or any other conditions (such as asthma).
As a further study reiterating
the same point, one can cite Orenstein (2005) whose review of a range of
investigations concludes that research does not implicate
thimerasol-containing vaccines or the MMR vaccine in the aetiology of autism or
infection. However, his presentation
also included a reference to continuing anxiety, reflected in a refusal among a
minority of parents to have their child treated with a generally-recommended
vaccine.
Orenstein acknowledges the
critical role of the medical profession in ensuring the safety of vaccines, but
argues, too, that the science behind all studies should be made explicit.
For example, he describes one
study which appeared to raise parental concerns about thimerasol and autism but
which was more ecological than epidemiological in that it did not take account
of changes over the recent past in diagnostic criteria and processes, or
the increase in the range of services available for children with ASD which might well have shifted the diagnostic
categorisations used.
Further, he was able to cite well-validated studies which have highlighted the non-comparability of the features of children with autism and those of non-autistic children with mercury poisoning. Studies purporting to show a link between vaccines and ASD commonly appear, he argues, to be short of the epidemiological study quality criteria.
There was also the study recently
conducted in Sweden and Denmark which demonstrated that, when thimerasol was
removed from vaccines, there was no corresponding change in the rates of autism
reported in either country.
Orenstein concludes by expressing
the hope that studies can shift away from this area towards more useful
research given that trying to find some link between vaccines and morbidity is
not leading to productive outcomes.
On the other topic ….. one notes
the study by Aman et al (2005) which has shown that around half of children
with pervasive developmental disorders and ADHD respond well to
methylphenidate.
However, it is recognised that
previous studies examining the effect s of stimulants on children with this
kind of comorbidity have yielded mixed results.
Further, in this present study,
there were found to be just short of 50% of the sample of children for whom the
efficacy of methylphenidate was demonstrated, so that there is a subgroup
of this population who are likely to benefit; it is not an intervention that
will benefit all cases.
It was also noted that the
beneficial effects were less than those observed among typically-developing children
with ADHD and that side effects were more common … such as decreased
appetite, interrupted sleep-onset patterns, irritability, and emotional
outbursts.
In other words, while the use of
psycho-stimulant medication is seen as a potentially useful intervention, it
will not be appropriate or free of adverse effects for more than a sub-sample
of cases, highlighting again the heterogeneity of this population and the need
for individual planning and close monitoring of initial outcomes of
interventions.
* * * * * *
Aman M. et al 2005 Some children with ASD and ADHD benefit from methylphenidate. Summary provided in Reuters Health Information (7.11.05)
Original article in Archives of General Psychiatry 62 1266-1274
Baron-Cohen S. 2006 Finding sex differences. Letter to The Psychologist 19(1) page 14
Orenstein W. 2005 Presentation to the American Academy of Pediatrics National Conference. Plenary Session. 11.10 05
Waddington E. and Reed P. (University of Wales, Swansea) 2005 Comparison of the effects of mainstream and special school placements on outcomes in children with ASD. Report for the SE Regional Special Educational Needs Partnership.
White R. 2005
The neuropsychology of autism and pervasive developmental disorders; an
expert interview with Simon Baron-Cohen.
Medscape Psychiatry and Mental Health
10(2) 14th December
2005
© Mike Connor 2006.
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