I have written Dr. Pantelis, et al., about this and another report, Aust N Z
J Psychiatry. 2003 Aug;37(4):399-406. I thought you may be interested in my
explanation of this:
"I have developed an explanation of schizophrenia that may explain your, et
al., hypotheses. It is my hypothesis that low dehydroepiandrosterone (DHEA)
prenatally and / or postnatally reduce brain growth and development. (My
principal hypothesis is that DHEA evolved because DHEA optimizes replication
and transcription of DNA. Therefore, all tissues, especially neural tissues,
are affected by availability of DHEA.) Early lack of DHEA would produce
brain structures of less robust growth which would be vulnerable to adverse
phenomena; this is the "early neurodevelopmental insult." Following growth
and development, DHEA acts to maintain and activate the brain. It is known
that DHEA exerts very positive effects on neural structures.
I also suggest the hormones cortisol and testosterone (in men and women)
adversely affect availability of DHEA. Therefore, a precipitating, stressful
events near/around puberty will combine to adversely affect the availability
of DHEA and adversely affect brain function. (It is my hypothesis that
cortisol, in fact, evolved to counteract the effects of DHEA; this is my
explanation of the 'fight or flight' response.) Since it is known that
cortisol is a neurotoxin, cortisol would adversely affect function and
structure, especially in a person of low DHEA. The early lack of development
due to low DHEA would produce weak structures. Continued exposure to
cortisol and testosterone would eventually cause degenerative changes in
easily affected structures, with more robustly built structures succumbing
later. Therefore, symptoms would appear sequentially, the type dependent
upon brain development. So, the same mechanism could explain various kinds
of differential destruction of brain structures and the timing of such.
Brain "shrinkage" is a phenomenon of all aging, given a sufficient life
span. I suggest this is due to the natural loss of DHEA of old age.
Schizophrenia would exhibit early shrinkage as a result of earlier loss of
DHEA and the combined actions of cortisol, the natural antagonist of DHEA. I
invite you to read my explanation of schizophrenia at
www.anthropogeny.com/physiology.html ; simply scroll down to "other" to find
schizophrenia or do a search for 'schizophrenia.' "
James Michael Howard
Fayetteville, Arkansas, U.S.A.
"lumberjack" <wfwoodland at yahoo.com.au> wrote in message
news:1e7476e8.0308171859.5d126ea3 at posting.google.com...
> The following might be of interest to the list ...
>> Brain shrinkage: early sign of schizophrenia?
>> The brains of people in the early stages of schizophrenia shrink twice
> as fast normal, Australian researchers have found, suggesting a
> possible new way to treat the illness.