[From Bill Powers (2001.02.12.0845 MST)]
Bruce Gregory (2001.0212.0532)--
If "loss of contact between awareness (or maybe just higher order systems)"
is an example of "a PCT interpretation", I consider my case to be made.
Perhaps a control diagram would make your point more clear to me.
I'm not sure what case you're trying to make; it would help if you said
what it is.
As to a diagram, I think a word picture might do almost as well. In HPCT,
there are control systems at many levels, which for various reasons I have
ventured to guess are concerned with control of intensities, sensations,
configurations, transitions, events, relationships, categories, sequences,
logical functions, principles, and system concepts, in ascending order. The
perceptions controlled at one level are functions of perceptions at the
next lower level (with the possibility of level-skipping in the perceptual
hierarchy). That is, without the lower-level perceptions being in
existence, the higher level perceptions that depend on them can't exist.
A higher-level system, in the present example at the level of categories,
controls by varying not the actions of the organism, but reference signals
at the next lower level: in this case, relationships. If the reference
signal stands for the relationship "key _in_ lock," then the
relationship-level system will send reference signals to lower systems
which bring that relationship into being in the perceptions at that level.
The same would apply to adjusting the fingers into the right relationship
with an object to pick it up. Those control actions, and the perceptions
they control, would exist entirely at the relationship level or below.
At the category level, I have conjectured, symbols become equivalent to
classes of perceptions. Terms like "key" and "lock" are equivalent to
categories of configurations, and "in" is equivalent to a category of
relationships. From that level up, perceptions are treated as discrete
symbols, and we can talk, think, and reason about the lower-level
experiences to which the symbols refer.
(To avoid sidetracks: I think there are also continuously-variable signals
at these higher levels).
What the blind-sight phenomenon suggested to me was that the category-level
systems were not receiving perceptual signals from systems at the
relationship level and downward. It would still be possible to send a
reference signal signifying "key in lock" or "fingers grasping object" to
the lower systems, and those system would carry out the control processes
needed to match the reference signals at the relationship level (using both
visual and tactile feedback), but the associated perceptions would not be
symbolized/categorized, nor would there be any perception of logical
functions, principles, or system concepts built on those lower perceptions
(the principle of "security," for example). If the person's awareness
operated primarily within those highest-level systems, the person might
well report (verbally) not being able to see the relationships or objects
-- because what the person consciously thinks of as a relationship or
object is actually a symbol or a category and not actually the lower-level
perception.
Of course the break could also be at a level higher than categories.
This is a straightforward application of HPCT. It doesn't prove that HPCT
is correct, but it suggests some testable hypotheses. Your remark that the
disconnect seems to be between the temporal cortex and the primary visual
cortex is circumstantial evidence about where the relationship and category
levels of HPCT might be located, if they exist and have been correctly
defined. I have guessed that language is carried out at the category,
sequence, and logic levels, so this is compatible with functions of the
temporal cortex -- the Area of Broca, for example. There might be other
phenomena that support these localizations, or that might provide a strong
reason to reject them or redefine the supposed levels.
I am following the normal sequence of processes involved in developing and
testing a model. The first step is always to fit the model to past
observations, adjusting its parts to get the best fit. The second step is
to use the model with the adjusted parameters to make a prediction of
something not yet observed. The third step is to compare the prediction
with what is actually found, and use the difference as the basis for
modifying the model. In the present case, I'm still at step 1; you can't go
on to steps 2 and 3 without some experimental resources. I've done as much
of that as I can using the resources I have (physical and mental).
Don't worry about the rolling doughnut -- it's a vestige of my blue-collar
upbringing. Just think of it as another picturesque way of telling someone
to go jump in a lake.
Best,
Bill P.