Richard's is another excellent synopsis! Wendy's and Richard's acts are
going to be very hard ones to follow, but you've given everyone a good
model.
rh> From: "Harrison, Richard" <RJH93PY@psy.soton.ac.uk>
rh> Date: Mon, 6 Nov 1995 11:27:10 GMT
rh>
rh> Z feels life is over but that "something keeps insisting I have to live."
rh> He had difficulty understanding or identifying things in the environment.
Some forms of brain damage are accompanied by depression (left
hemisphere damage, typically) and others by upbeat mood (right
hemisphere more often than left). Z had mixed injuries on both sides,
and his depression was probably a completely understandable reaction to
a sudden, huge, all encompassing handicap like the one he had.
rh> 3 months after being wounded Z meets Luria. "He did not understand
rh> my questions at first, and even after he did, he had difficulty
rh> replying." Z lacks meaning , e.g. "Where's my left hand?.....What
rh> does right mean?....." However, he kept an immediate grasp of the
rh> world and sensitivity to experience allowing him to evaluate each
rh> and every failure.
The language problems are called aphasia, usual left-hemisphere damage.
The body location problem is called autotopagnosia and is usually
right-hemispheric.
rh> There was damage to the tertiary area of the visual cortex but not
rh> to the primary or secondary areas. This means that whilst he could
rh> still see and perceive discrete objects he could not combine
rh> impressions into a coherent whole. Also, the tertiary area of this
rh> area (of the left hemisphere) are involved in language functions. As
rh> well as a means of communication language is fundamental to
rh> perception, memory, thinking and behaviour. "It organises mental
rh> life."
Being able to see but not recognise is called visual agnosia, more right
than left-hemispheric. Being unable to name objects is anomia, more left
hemispheric. Language in general tends to be left.
rh> Z's frontal cortex was not damaged, hence the ability to "recognise
rh> his defects and wish to overcome them."
The INABILITY to recognise one's defects would have been anosognosia --
agnosia for your own infirmity. He did not have that; he knew what he
had lost.
rh> At first he could not perceive a thing then, when he could,
rh> fragments didn't form complete objects. He had to guess what
rh> assembled fragments meant. Also, the right side of his visual field
rh> was "an even grey vacuum".
After brain injury, there is usually a period of recovery, but what is
not recovered within the first year or so is usually lost for good,
apart from very small improvements.
rh> His sense of his body had changed. He experienced fragmentation of
rh> his body and certain body parts would feel large or small. For
rh> example, "...my head is the size of a table". Also, he forgot where
rh> body parts were and had to `hunt' for them.
Autotopagnosia. Other body image distortions and agnosias.
rh> He adjusted to these body problems but other disturbances persisted.
rh> Examples of `spatial disturbances' were not knowing which hand to
rh> extend to shake hands and getting lost when going for a walk. When
rh> he left hospital and returned home he did not recognise his home
rh> town. Indeed, "space `made no sense to him'" and so it lacked
rh> stability.
Spatial agnosia. To the extent that he had trouble organising movements
in space, he would also have had apraxia. With Z you are really sampling
the A-Z of neuropsychological disorder.
rh> The realisation that you can't read must be as confusing as it
rh> is devastating.
Alexia (and in Z's case, pure alexia, without agraphia [inability
to write] or primary visual disorder). The most puzzling case of all.
rh> Relearning the alphabet was a very slow process. Progress was made
rh> by associating a letter with a word that began with that letter.
rh> Reciting letters out loud was more successful than visualising
rh> letters. It took an incredible effort to make small improvements.
All this suggests that what little progress Z made (he never really
overcame his alexia) was being made by some means OTHER than the way we
normally read. The relearning was piece by piece, slow, analytic; it
never become the fast, holistic act that we perform when we read. He had
to memorise letters as if they were nonsense patterns, and he could not
put them together: every extra bit required more specific memorisation,
instead of the automated skill that we have. (There is a brain area that
is thought to be dedicated to reading: Exner's Area, in the left frontal
lobe.)
What's hard to understand (and this is both the seduction and the
frustration of neuropsychological data) is how it is possible to see
normally, to think normally (in fact, above normally, since Z is
obviously highly intelligent, otherwise his struggle would have been
even less successful), to be able even to learn the names of letters,
yet not to be able to put it together: It reminds you of the difference
between human children and chimpanzees in their signing ability: Up to a
certain age, they are equal, and then the child takes off and races
straight through to language, whereas for the chimp it remains the same
slow, sign-by-sign memorisation.
rh> Writing was even harder than reading to start with. "I'd just
rh> forgotten how to use a pencil." Then he discovered he could write
rh> automatically (as opposed to the way children do) even though he had
rh> trouble reading his own writing. After intensive training he could
rh> almost write as well as he did before being wounded. He decided to
rh> write a journal describing what had happened to him and the struggle
rh> it took to start recovering what he had lost.
The reason Z THOUGHT he couldn't write is quite understandable: How can
you write if you can't read (even though you can see and think just
fine)? But once he started to do it (these days neurologists tell such
alexics to do automatic writing, rather than waiting for them to
discover it themselves), the writing flowed. But what does that mean?
How could he form the ideas into letters with his mind and hand and not
do the reverse when reading them with his eye and mind? It would seem
that the process ought to be invertible...
rh> He worked on the journal everyday for 25 years. Although he could
rh> write he had great difficulty being able to express ideas in words.
rh> Hence, very slow progress.
It is not unusual that highly intelligent (and even not so intelligent)
patients, trapped in a neurologically handicapped brain spend all their
energy in trying to make sense of their condition (as long as they don't
have anosognosia!). After all, these people are not crazy and there are
not mentally retarded. Bodily handicaps one just has to learn to live
with (loss of limbs, even paralysis). But brain handicaps that effect
your cognitive capacity -- as opposed to just your body-movement
capacity, are relentless puzzles, not just for the minds of their
unfortunate victims, but also for any of us who try to understand what
it is LIKE to be in such a state: With a psychotic there is an easy
answer: his thoughts are disordered. With someone retarded, it is simply
an intellectual incapacity. But with Z...?
rh: Why did he write?
rh> A question he asked himself many times, especially as it was such a
rh> demanding and exhausting task. He decided it was worth it as he was
rh> not fit for anything else. Through his writing he could create a
rh> coherent view of what his experiences and desires were. Basically,
rh> it gave him a reason to live.
And if you will just put yourself in his place for a moment, it is not
hard to understand why, in the only life one is given to live, trying to
make sense of this all-embracing disorder should turn out to be one's
overwhelming quest. In a sense, we are puzzling over cognition and
consciousness for very similar reasons, aren't we?
rh> So, setting the scene for the next few chapters, Luria says "if we
rh> follow him step by step, we may unravel some of the mysteries of the
rh> human brain."
But of course the frustrating thing is that neither Z himself, nor
neuropsychology, has been able to answer the deep questions -- either
about the nature of the deficit or about the brain function underlying
it -- from studying the mysterious symptoms of brain damage. Z is in
one respect very much like HM, the famous amnesic patient who had both
his hippocampi removed for epilepsy in 1954 by Penfield and who has not
been able to form any new memories since then (so much so that every
time he is told that his father has died -- he died years AFTER HM's
operation -- he breaks down as if hearing it for the first time:
because he IS hearing it for the first time). In the weeks after his
operation (when, as I said, most recovery is made), HM, when asked how
he was doing, would say "It's all beginning to come back to me." He's
been saying that ever since. Life's like that often, with our quests;
neuropsychologists are that way about their lifelong quest to understand
the mind: The make slow painful progress, but the mystery remains...
rh> Z's memory problems were the ones that most disturbed him. He
rh> couldn't remember the words for objects and if he could it took a
rh> lot of effort to do so. He had to "learn to recognise objects and
rh> try to associate them with words."
Which suggests that the natural way we learn to recognise objects may
not be just by trying to associate them with words. Remember S's
abstraction problem? S sounds like the opposite of Z (and certainly of
HM): He remembers everything he perceives. But does he perceive, and
especially RECOGNISE everything? Hypermnesia (the opposite of amnesia:
supermemory), synesthesia and eidetic imagery (very vivid imagery:
"Photographic memory") are, after all, usually correlated with brain
damage...
rh> Two points are re-emphasised. Firstly, that Z lost the link between
rh> words and their meaning. And secondly, that he had to actively
rh> search through lots of familiar words before stumbling on the right
rh> one for a particular object.
Word-finding difficulties we all get to sample (moreso as we get older!)
with things like the tip-of-the-tongue phenomenon, when you know you
know a word or name, but just can't quite get to it. Imagine if
everything were that way! But calling it a "disconnection" between words
and meaning (as many neurologists and neuropsychologists do, based not
only on the cognitive symptoms, but the anatomy too) is really just
renaming the puzzle: How can such things be disconnected in the same
head: Reading from writing, speaking from understanding, words from
meanings, letters from meanings, etc.? What is the real difference
between the fast, natural means of making the "connection" that we use,
and the slow, awkward, and ultimately unsuccessful means Z is reduced
to?
rh> Luria suggests that the problem with Z's `speech-memory' originates
rh> from the disruption of the parts of the cortex that control the
rh> analysis and organisation of complex associations into a coherent
rh> framework. So, for example, even if he did remember a correct word
rh> then associations would continue and he would forget the right word.
This explanation (of Luria's) is obviously too vague and general; to the
extent it means anything at all, it is really just a restatement of the
symptoms: What WOULD count as an explanation?
rh> Analysis of a short comprehension test shows Z could only understand
rh> one word at a time and not combine them to form the intended image
rh> main point. This problem also meant he couldn't formulate and
rh> express his own ideas coherently.
rh>
rh> Luria demonstrates how intricate grammatical construction can be in
rh> instances such as sub clauses, inversions and the implications of
rh> different case endings.
These days such disorders, using the "double dissociation" technique I
mentioned (find patients with deficit A but not B, and others with
deficit B but not A), have been separated into more basic disorders, of
which one important one is a syntactic one: We get a lot of information
from word order (subject/object, active/passive) and from word endings
(present tense, past tense, singular, plural, 3rd person, etc.). This
information is as reliable and automatic as our letter recognition in
reading, but with people with certain kinds of grammatical aphasia, they
are not reliable and automatic, but become the slow, painful, ultimately
unsuccessful associative process that Z also used with letter
recognition. This overall inability to use the syntactic rules that make
it possible for us to exchange information verbally was a huge handicap
for Z.
Myrna Gopnik
http://cogsci.soton.ac.uk/~harnad/csctalks.html#gopnik
spoke here at the Cognitive Sciences Centre about what seems to be a
hereditary brain disorder that specifically causes this kind of
grammatical disorder only.
rh> Z was only able to understand sentences in which the word order
rh> coincided with the sequence of actions. e.g. `The man read the paper
rh> then had breakfast' but not `The man had breakfast after reading the
rh> paper', and he couldn't differentiate between `The circle over the
rh> cross' and `The cross over the circle'.
rh>
rh> He relates Z's inability to grasp linguistic relationships to his
rh> difficulties with spatial relationships and suggests these two
rh> functions are based in the same area of the cortex.
As I mentioned, more recent work suggests that this disorder is not
spatial but specifically grammatical.
rh> His problems in understanding grammatical constructions led to the
rh> impossibility of recovering any knowledge he had acquired before he
rh> had been wounded. e.g. counting, playing chess etc.
These may or may not be connected disabilities. Remember, Z has MANY
disabilities, some functionally related, some not. It requires
dissection by the double-dissociation technique to sort out what
is and is not functionally intertwined with what. See:
http://cogsci.ecs.soton.ac.uk:80/~bbs/Archive/bbs.farah.html
rh> Luria concludes by saying Z still struggles on with his writing, not
rh> understanding why this happened to him, but still wishing to wake up
rh> from a dream.
"It's all beginning to make sense..."
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