did anyone came with a theory so far about the cause of ADD. othwer
than things like "they have smaller right brain", or "birth problem"
or "genetic problem" did anyone has a better way of explaining it?
what I'm looking is a synopsis / summary of all the suggested theories
on the subject. and the price will rise significantly if I see it goes
somewhere.

<A number of studies have identified several possible causes of ADD.

Enviromental causes. 
Toxic chemical compounds have been suggested as a possible cause of
ADD. These include pesticides, fluoride, mercury, marijuana,
cigarettes, coffee, monosodium glutamate, artificial food additives,
alchol, aspirin and cosmetics. Compared to 30-50 years ago there are
more neurotoxic chemicals in the environment. It is thought that these
substances can damage the development of the fetal brain which has no
functional blood brain barrier to protect it from toxic substances.
Research carried out in these fields can be found at
http://www.chem-tox.com/pregnancy/learning_disabilities.htm

ADD linked to dioxins.
A study by Dr. Peter Hauser has identified that children exposed to
environmental toxins like dioxins pre-natally and during infancy can
suffer neurological problems. It has been suggested that the
underlying mechanism may be disruption of the normal action of thyroid
hormone. Details of the study can be found at
http://www.sciencedaily.com/releases/1998/01/980113155609.htm

Damage to sperm
Research has shown that some birth defects may be caused by the
exposure of the father to chemical compounds during the 65 days before
conception (whilst the sperm are developing in the testes). Research
carried out in this field can be seen at
http://www.chem-tox.com/pregnancy/sperm1.htm

Abnormal blood flow.
One study has found that add may be related to abnormal blood flow in
the brain. The research found that patients with ADD had abnormal
blood flow in the mesial frontal lobes. For details of the study see
http://www.chem-tox.com/pregnancy/LDbrain.htm

Dopamine deficit.
A study has shown that ADD is linked to a dopamine deficit. Details of
the study can be found at
http://www.sciencedaily.com/releases/1998/08/980814063830.htm


Ultrasound.
A study into ultrasound also showed neurological changes when the
procedure was used more than once. See
http://www.chem-tox.com/pregnancy/ultrasound.htm>

<Additional links:>

Abnormal blood flow>
<http://www.chem-tox.com/pregnancy/LDbrain.htm>

<ADD>
<http://www.marylandadd.com/>

<Causes of ADD>
<http://www.unhinderedliving.com/ADHDcauses.html>

<Mapping susceptibility genes for add>
<http://www.adders.org/research11.htm>

<Study shows brain chemistry defect is key to ADD>
<http://www.sciencedaily.com/releases/1998/08/980814063830.htm>

<Differences in brain function found for ADD>
<http://www.sciencedaily.com/releases/1998/11/981124063106.htm>

<What causes ADD>
<http://www.add.org/content/research/causes.htm>


<Search strategy:>

<add brain causes university>
<://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&q=add+brain+causes&as_q=university>


<add brain causes>
<://www.google.com/search?hl=en&lr=&ie=ISO-8859-1&q=add+brain&as_q=causes>


<Hope this helps.>

---

Request for Answer Clarification by eran-ga on 08 Mar 2003 02:30 PST

Thank you so far...

is there a theory suggesting incompatibility between the faster
electrochymical activity in the right hemisphere to a relatively
slower left hemisfare performance as a possible explanation? I'm
wondering why no one ever ventured into that path? I'm not talking
about the phisical causes, I'm talking about the actual explanation,
in neurology terms, to that wide spread phenomena. its obvious to me
that something physical is causeing, or catalyzing evolution of such a
deficit

---

Clarification of Answer by belindalevez-ga on 08 Mar 2003 14:41 PST

<Dr Billy Levin has a theory that an overdeveloped right hemisphere
and or immaturity of the left hemisphere gives rise to learning
problems. Details of the research and his explanation can be seen at
http://www.adders.org/research1.htm>

<Hope this helps.>

One of the problems with determining the "cause" of ADHD is that there
is not likely to be one single cause.  Just as their is no single
cause for cancer because it is not a single entity, there is no single
cause for ADHD.  Part of the  problem is that there is no real,
well-accepted test for ADHD.  Instead it is generally defined by
having a sufficient number of symptoms of attention/impulse control
problems of sufficient severity.  Attentional control involves a very
complex interaction of different factors within the brain.  Problems
with multiple different parts of this system can result in a set of
symptoms which meet the behavior based definition of ADHD.  In
addition some children get the diagnosis even without meeting the
criteria.  This makes it hard to determine a cause because in reality
the researchers are dealing with a mixture of different disorders. 
The set of symptoms which define ADHD have definitely been linked with
toxin exposures, including alcohol use by pregnant women, and lead
exposure, among many others.  It has also been linked to some genetic
syndromes.  Hormonal problems such as low or high thyroid levels can
cause these symptoms.  There seems to be a familial aspect to it as
well, though whether this is genetic or due to the environment the
child is brought up in is not entirely clear.  Also, because it is
such a nebulous group and it can have such a major impact on a child's
behavior and school performance, it is a field that is rife with
quacks proposing a cause/cure that may not be supported.  Many of
these include various unsubstantiated dietary manipulations.  In
general, the internet has greatly helped in the spread of these types
of quackery.  I would recommend in dealing with attentional,
behavioral, or school problems, that the child be evaluated by a
physician whose agenda is not merely to test for ADHD, but to get to
the actual problems -not to worry about labeling, but to individualize
evaluation and treatment to the patient and his or her unique needs.

I am not a doctor or of any medical authority, but one quite
interesting "theory" into the origin of ADD is mine.  You can read it
at http//www.freewebs.com/addresearch/ .  Adrenal fatigue IS present
in ADD and like some Russian scientists have said it characterizes it.
 Cortisol is low (without taking stimulants), epinephrine is low and
norepinephrine is also low.  These are adrenal hormones and indicate
adrenal fatigue.  Dopamine is produced in the adrenals from tyrosine
and dopa and then it is converted into norepinephrine by
dopamine-beta-hydroxylase.

From these abnormal chemical levels you can say:

1. Low cortisol might cause blood sugar instability due to the lack of
gluconeogenesis effecting the glucose supplies of the brain.  It is
proven there is a poor glucose metabolism in ADHD brains. 
Norepinephrine and epinephrine also effect glucose levels.

2. If you want to go the neurotransmitter route then there may be
something blocking the conversion of dopamine to norepinephrine. Or if
dopamine really is low and not high, then there may be some enzyme
blocking the conversion of dopa into dopamine or tyrosine into dopa. 
Maybe it is due to a mineral or vitamin deficiency which is in turn
caused by another malfunction.

3.  Tryptophan and serotonin levels have also been implicated, but
since antidepressants don't effect ADD and ADHD, then most scientists
don't believe the serotonin "theory."  I have yet to research to find
if there is low serotonin levels.  I suspect this might be due to a B6
deficiency like pyroluria if I find it.  Usually B6 deficiencies go
along with adrenal fatigue.

So, as I have implyed, the more prominent "theories" of the origin of
ADD and ADHD focus on the adrenal hormones and dopamine, which also
comes from the adrenals. Some, like me, say that the glucose
relationship is part of it.  Others say it is the neurotransmitter
function of norepinephrine.  Still others say it is dopamine. Finally,
some say it is serotonin. If you combine all these "theories" you
still have to admit that there is an adrenal malfunction that needs to
be solved.

If you can read scientific articles, then you might want to research
medline Entrez Pub Med, like I have, reading the abstracts for the
sources I sited on my web page.  I hope I have saved you some time.