> From: "Chatwin Judy" <JAC295@psy.soton.ac.uk>
> Date: Wed, 15 Nov 1995 14:18:42 GMT
>
jc> few improvements or real changes occurred during the 25 years
jc> other than those specifically mentioned.
After brain damage, most of the major recovery and reorganisation, if
there is to be any at all, occurs early, within the first few weeks or
months after the injury. This often involves other parts of the brain
taking over the functions. But after that, improvements are slow and
minimal, being based mostly on cognitive "strategies" for overcoming
perceptual and cognitive handicaps that themselves never get any better.
It's as if an injured knee recovers up to a point, but the rest is just
your strategy for dealing with your permanent limp: Except these mental
"limps" are much more puzzling than physical ones ever are.
jc> On 2nd March 1943, Zasetsky suffered a bullet wound to the head which
jc> resulted in a lesion in the brain - this caused severe damage to the
jc> part of the brain which is essential for making sense of the world,
jc> i.e. the combining of separate parts of information to make a whole
jc> which can then be understood.
Well, let's say a part of the brain was injured that had the effects
that Luria and Z described. Whether the injury was in the part that "puts
information together" is less clear, nor is it clear what that function
would really be (apart from its effects, namely, the things Z could no
longer do). This is the main problem of neuropsychological explanation:
It can tell you what kinds of deficits an injury in a particular
part of the brain will have, but it can't tell you what that part -- or
any other part -- actually does; in other words, if that area IS
responsible for "putting information together" (whatever that means):
how does it do it?
jc> Initially, he had no thoughts or memory at all but gradually some
jc> things began to come back
This is that first period of recovery; but as you see, it is partial,
incomplete, and after a certain there is no further improvement.
jc> he would
jc> recognise an object but could not remember what the word for it was and
jc> so he adopted a method of searching for the word, this could take him
jc> hours or even days before the right word was found.
jc> Objects would appear familiar but the word he wanted would be 'on the
jc> tip of his tongue' and yet he could not find it.
This is called anomia, or the inability to find the names for things.
We don't know how we find the names of things either. They're usually
just there whenever we need them. The "tip of the tongue" phenomenon
gives us a small state of what it was like for Z at all times.
jc> He had no
jc> vocabulary and therefore could not express himself or communicate.
His anomia is one thing: that's the inability to find the name of an
object even though one knows what the object is (and one knows, or once
knew, its name). Aphasia would be the inability to speak or understand
speech. These are separate deficits, because you can be aphasic without
being anomic, and anomic without being aphasic.
jc> he could recall nothing he had consciously learnt. He
jc> could not do simple arithmetic learnt in primary school. He set out to
jc> relearn much of what he forgotten. This proved to be a far greater
jc> task than he had envisaged. As soon as he learnt a new concept he
jc> forgot it again.
In a way, Z has a clearer idea of his limitations and his relative
helplessness in everything he is able to do than we are, because we are
used to having an intact brain serve us everything on a platter and yet
take the credit for doing it ourselves! But look at Z, painfully
learning a small fact, only to keep forgetting it, while we take our
automatic recall for so many things for granted...
jc> He could recite the alphabet but could not recognise
jc> letters but gradually he was able to put letters together by going over
jc> the entire alphabet until he came to the letter he was searching for.
In the later re-learning phase, after the first dramatic recovery, it is
clear that the patient is managing to do a lot of things they used to
do, but the "wrong" way -- wrong in a way that may be similar to the way
animals can be trained to do things we do, but again, they are doing it
the "wrong" way: chimpanzee "language" training is an example: It takes
so many training trials before they learn to name things correctly, and
even more to get them to use the "name" to actually name things; you
have to conclude that despite the behavioural similarity, inside,
something very different is going on. Same with Z.
jc> He learnt to write again by doing it spontaneously, not thinking about
jc> it, he was not always able to read what he had written
Ponder this condition for a while: This is alexia without agraphia: Loss
of the ability to read with retention of the ability to write (although
there is some recovery of the reading ability). How can this be? What is
it like to be able to write but not read? Don't they feed from the same
fountain? Don't say the writing "centre" is disconnected from the
reading "centre": What do those centres do? And how can the writing one
work without the reading one?
This will come up again when we discuss the split brain.
jc> Can you imagine waking up one day with no knowledge of what has gone
jc> before? Gradually your early life starts to re-emerge and you have in
jc> your mind images of people and places but you can't remember facts;
jc> where you live; what 2+2 is; how to attract someone's attention; what
jc> is that thing called that is of a certain size (you do not know what is
jc> big and what is small), black, soft, makes a noise (purrs), sits in
jc> front of that hot, bright thing (fire), sleeps a lot - oh, what is it
jc> called - I know I know it, I have seen it before, it is familiar - what
jc> is it called, the word begins with a 'c' - I think, oh come on - I know
jc> - a cat!
If you can imagine it, and can also figure out what it is that you've
lost -- not the behavioural ability, we already know that: the brain
function that you lost, the one that generated the behavioural ability
-- then you have the beginnings of a neuropsychological explanation.
jc> A man who went through this process every time he wanted a word wrote
jc> 3,000 words over 25 years, some days he wrote a line and on a good day
jc> he managed half a page. His perseverance and his determination to try
jc> and find his memory again can only be admired.
He was trying to do both introspection and rehabilitation on his
condition. Proust's "A la Recherche du Temps Perdu" ("In pursuit of
time lost") is a good description of Z's quest, his lifelong attempt
to unravel the mystery of what he had lost, and to try to put it back
together again, is not all that different from our own quest: Z at least
has the advantage of knowing what he doesn't know; we tend to take a lot
more of it for granted...
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