John at faraway.com.au
Wed Oct 17 09:24:53 EST 2001
"Liar42" <liar42 at aol.com> wrote in message
news:20011013220650.15187.00001852 at mb-fa.aol.com...
> >And long term memory is NOT directly by itself connected to short term
This line has to be a bait. If not connected, then how is long term memory
> Apart from that you do not discern which of the long term memory systems,
> two of them my own I is getting data from there, so we are connected.
> > no - it (LTM) is established in another domain directly and
> indirectly (through the Corpus Callosum, aka the Faux Fax of Calvin)<
> Why does that sound like b.s. to me?
It is my understanding that Kandel and Co established LTM processes through
studying the humble Aplysia(snail), which to the best of my knowledge is not
in possession of a corpus callosum. Not to mention any other number of
species lacking the same but seem capable of establishing LTM. I haven't
read Calvin's work, and his Darwin Machine idea sounds like Edelman 20 years
ago which sounded like some Italian neuro in late 60's I think re reentrant
and probabilities and the reality that the immune and cns are the only 2
memory systems capable of LTM and arise from a common embryological origin.
William Calvin is good stuff, I've saw him on TV interview science special
many years ago where he described Gerald Edelman as making the rest of us
look rather dim(and if I look at Edelman's record I have to agree). I'll
need to read this text one day to see what he's on about.
What of split brain patients? I can't recall any loss of LTM in the same.
Other cognitive changes for sure, and probably some memory dysfunction, but
not global LTM loss. Caveat: usually the anterior commissure remains intact
and there remains thalamic connections. Not sufficient though, should remain
What of those who have undergone hemispheroctomy(spelling!) - removal of
large portion of one cortex to control intractable epilepsy? These people
will experience deficits to varying degrees, but the inherent loss of so
many collosal connections should leave them without any real capacity for
intelligence if you believe in the gross neuroanatomical substrate idea for
human intelligence try having a look at the work of John Skoyles, a British
dude. You can find it at the socog archives in the UK. Not well accepted,
but he does collect some very interesting cases of gross brain injury and
There are some born without a callosum, usually low iq, circa 90 in one
study I read (I should call that low, I barely make 100), but these people
are quite capable of forming LTMs. As for my corpus callosum, I still have
trouble discerning left from right, so I must be rather thick.
> Have you ever bothered to consider the Corpus Callosum as transconnections
> between brain halves?
> > (...) When ideas compete (in our brains) for attention,<
How does an idea compete?
> Hae?! If I have ideas, they do not compete for attention, but I have them
> think about them.
> Say I were to consider if it is better to call you an idiot or some nutter
> mistakes his belief for fact and therefore writes b.s. like facts,
> then there is no competition for attention, they are just parallel
> where I might consider their values, like that one is shorter and the
> more explicit, etc.
> What however might distract me just slightly is the laughter in the wake
> charming diplomacy.
> > they occupy hexagonal areas (Hebb's cell-assembly),<
> Now, if you were an Amargeddon player I might wonder if you stared too
> some hexagons there.
Overcast in Berlin?
> Some day maybe bother to notice that neither all brain cells nor magic
> or whatever you call energy systems in the brain
> are tending to be all in hexagonal stages in the brain.
> > and the one with the greatest area usually wins.<
> Total b.s.
I dislike singular explanations for complex things like attention. There are
many types of attention, it is not simply a matter of area of excitation but
degree of excitation or type of excitation oh it could be many things and
there are others here who can address those spike firing and memory storage
and signal processing questions much better than me. In terms of attention,
one of the best authors I have read is Patricia Goldman-Rakic, and I believe
she is extending the analysis to the level of now being able to measure the
activity of many types of synapse for a single cell. From my current reading
and the advice of my mentor, it is my understanding that attentional
mechanisms are mediated through at least the pfc - bg network, to conceive
of attention as simply some mass geometric function is to fail to understand
that attention is not a single thing, our attention is mediated through a
variety of processes but in relation to most temporally frequent attention
the pfc bg linkage seems to be critical, as does dopaminergic D1\D2 balance.
Some antipsychotics work by blockading D2 receptors. If you want to read
something interesting about that,
Castner, S.A., G.V. Williams, & P.S. Goldman-Rakic. 2000. Reversal of
antipsychotic-induced working memory deficits by short-term dopamine D1
receptor stimulation. Science 287: 2020-2022.
I do not think we will understand this matter of attention unless our
understanding incorporates the consideration of the dopaminergic network.
I'm sure Willilam Calvin knows this so am interested to know how he
addresses this aspect of the question.
> >William called it his Darwin Machine, <
> Sounds like an insult to Darwin, unless he came up with such mental b.s.,
> >and all I can say is that I'm awed over his intelligence.<
> Hexagonal b.s.?
Never heard of it. My understanding is that the principal anatomical unit of
the cerebral cortex is the pyramidal column, which can vary in size etc but
essentially retains its integrity as a structure. If there exists these
hexagonal structures, shouldn't this be reflected in the structural changes
in pyramidal columns post learning? Is this documented in Calvin's work?
Doesn't the requirement for hexagonal structures place unnecessary
constraints on memory formation?
> One might be more awed over your degree of "intelligence", but for
> >But alas, I still have to study more - <
> Good idea.
Raining in Berlin? Good news. Rained for two days. Drought broken here.
Wallabies will get fat again.
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