hippocampal 'atrophy'

Kenneth Collins k.p.collins at worldnet.att.net
Thu Aug 22 19:18:29 EST 2002


Er... what are you saying "no" to?

I stand on what I've posted.

That you see "cheap shots" and "insults" and "spuriousness" and
"ill-founded-ness" in-it, is your business.

I'm just working in the way I've always worked, which works, and in
which I will continue to work, because it works.

But I do find it 'interesting' that, in a thread that's stressing
"stress" in experience, and discussing the 'discord' within
biological vs.experiential-derivation of biological-modification, you
'skip' all that, and address only chemo-intervention stuff :-]

k. p. collins

John H. wrote in message ...
>No, recent fMRI studies in Toronto demonstrated that the efficacy of
the
>SSRIs may well be mediated by their ability to reduce hippocampal
activation
>and stimulate neurogenesis in the dentate gyrus. Cortisol reduces
>neurogenesis, probably via the mutual antagonism of GR occupation
and nfkb
>transcription; nfkb being essential not only for LTP but also
neurogenesis
>or probably just any any-cell-genesis. In short, the drugs, while
having
>their problems (I have bad reactions to SSRIs), can work remarkably
well in
>some people by encouraging hippocampal rehabilitation and
facilitating
>reactivation of the frontal cortices which tend to be quieter in
depression.
>
>It has been tested and you are wrong. Stop quoting your own ideas
and have
>the humility to appreciate that other people just might be right on
>occasion. I am sick to death of seeing people take cheap shots.
Don't insult
>my intelligence with spurious ill founded propositions.
>
>John H.
>
>
>"Kenneth Collins" <k.p.collins at worldnet.att.net> wrote in message
>news:Td199.25634$Ke2.1944930 at bgtnsc04-news.ops.worldnet.att.net...
>>
>> Ian Goddard wrote in message <3d62f359.92179446 at news.erols.com>...
>> >
>> > The following reviews a new book by Douglas Bremner, an Emory
>> > University psychiatrist who argues that many major psychiatric
>> > conditions are the result of environmental stressors.
>> >[...]
>>
>> >"When patients are having flashbacks, as my veteran was, they are
>> >unaware of what is going on in the present," said Dr. Bremner.
>> >"Patients often describe flashbacks as if a movie were playing in
>> >front of their eyes, complete with visual images, sounds and
>> >smells." Dr. Bremner theorized that the flashbacks could involve
the
>> >same brain areas that are affected by seizures, most importantly
the
>> >hippocampus, which is affected in 80% of epilepsy cases.
Subsequent
>> >PET (positron emission tomography) studies with trauma victims
>> >showed a significant and direct link between a reduction in the
>> >volume of the hippocampus and PTSD.
>>
>> The relatively-recent [~3 years ago] findings with respect to
>> hippocampal stem-cell proliferation probably indicate that such
>> hippocampal 'atrophy' is, at least to a degree, 'reversible'.
>>
>> The 'atrophy' correlates strongly with the survival-necessity
>> inherent in prolonged 'stressful' environmental circumstances, and
>> is, itself, commensurate with TD E/I-minimization in that it would
>> reduce information-processing options to a relatively-small subset
>> that's dictated by the environmental stressors, thereby,
augmenting
>> the information-processing 'power' that can be 'poured-into' a
>> relatively-narrow range of survival-pertinent behavioral
>> manifestations.
>>
>> 'Reversibility' of stress-induced hippocampal 'atrophy' would
enable
>> post-stress-reaction return to 'normal' information-processing.
>>
>> The 'catch' is that, if 'modern' psychiatric practice 'intervenes'
>> inappropriately, such might, itself, interfere with post-stress
>> hippocampal stem-cell proliferation. The 'treatment', itself,
>> interferes with, and 'blocks' return to 'normal'
>> information-processing because the 'treatment' is, itself, a
>> stressor - so the 'treatment' does just the opposite of it's
intended
>> purpose.
>>
>> This's all testable.
>>
>> I'm not familiar with the state of the art in animal-stress
>> experiments, but a swim-tank design should work.
>>
>> Use no blood relative subjects. All subjects same-sex.
>>
>> Populate an enriched environment with 3-times the subjects that
will
>> be subjected to the stressor [1/3 will just remain in it]
>>
>> Populate an impoverished environment with the same number of
>> subjects.
>>
>> Pre-stress, have subjects gain relatively-long-enduring
familiarity
>> within a generously-rich experiential environment. Minimal
handling,
>> plenty of food, lots of 'toys', exploration opportunities,
exercise
>> equipment, etc. 'Shoot the moon' on enriching their environment.
>> Allow them relatively-long opportunity to become familiar with the
>> environment. Do not introduce new subjects after a set of subjects
is
>> inserted into the environment [mid-test unfamiliar stuff confounds
>> results].
>>
>> Do the stressor. 2/3 of subjects from the enriched environment
>>
>> Post-stress, allow half the subjects to return to the enriched
>> environment with which they're familiar. [Since there're no blood
>> relatives, the absent 1/3 enriches the environment further.]
>>
>> Remove 1/3 of the animals in the impoverished environment, and
place
>> the other half of the stressed animals into it.
>>
>> Get it? The pre- and post-experiment impoverished population has
the
>> same number of animals, but some were replaced by stressed
animals.
>>
>> Allow an aclimation period of the same length as the
pre-experiment
>> acclimation period.
>>
>> Get-it? The impoverished environment is, itself, a stressor
because
>> 1. it's unfamiliar, and a large change from the familiar
>> pre-experiment enriched environment, and 2. because there'll be
>> 'conflict' between the animals long-familiar with the impoverished
>> environment and the post-stress animals unfamiliar with the
>> impoverished environment.
>>
>> Prediction: there'll be an observable hippocampal-rebound
>> differential between the subjects that're returned to the enriched
>> environment with which they're familiar, and the subjects that're
>> placed into the impoverished environment with which they're
>> unfamiliar. Latter-group, less-rebound.
>>
>> The experimental design needs to be precise in all it's facets.
>> Freedom in the enriched environment. Limited opportunity, and
>> 'obnoxious' strangers in the impoverished environment.
>>
>> Tweak-it to enhance it from this "top-of-the-noggin'" description
to
>> conform with best-practice with respect to the experimental
designs
>> that demonstrate the hippocampal atrophy in animals.
>>
>> What you've got here is an analogue for what a stressed-out human
>> encounters when he's virtually incarcerated in a
>> psychiatric-'helping' place.
>>
>> Other trials might replace the impoverished environment with
>> excessive handling, chemical intervention, etc.
>>
>> The hippocampal-rebound differential will disclose the impact of
not
>> just enabling folks to be Free to find themselves, post-stress.
>>
>> If you do this experiment, since I proposed it, you are
>> Ethically-bound to allow me to review your experimental design and
>> results [no self-fulfilling-prophecy-via-sloppy-design allowed :-]
>>
>> Get in the spirit of it. Work to develop as close an analogue of a
>> post-stress 'hospitalization' experience as is possible.
>>
>> What I'm getting at is that what has become 'deemed to be helpful'
>> with respect to recovery from 'stress', is actually deleterious
with
>> respect to such recovery.
>>
>> There're =many= variations of this general experimental design,
all
>> of which will yield significant results with respect to 'helping'
>> environments.
>>
>> The thing that makes this possible is that, animal or Human, it's
all
>> 'just' TD E/I :-]
>>
>> k. p. collins
>>
>> >[...]
>>
>>
>
>





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