Reorganization and Trial-and-Error - WHOA!

[From Ted Cloak (2009.08.04.1318 MST)]

Whoa! I just flashed on the big
mistake, PCT-wise, in Pinker’s metaphor; which I think beautifully
illustrates the limitation of conventional cognitive neuroscience as a
behavior-explainer.

Just for fun, who else can spot
it?

Regards, Ted

Ted Cloak (2009.08.03.1606 MST) (Reaching back a few
months)

/SNIP/

This from Pinker, Steven: How the Mind Works:

“Controlling an arm presents a new challenge. Grab the
shade of an architect’s lamp and move it along a straight diagonal path from
near you, low on the left, to far from you, high on the right. Look at the rods
and hinges as the lamp moves. Though the shade proceeds along a straight line,
each rod swings through a complicated arc, swooping rapidly at times, remaining
almost stationary at other times, sometimes reversing from a bending to a
straightening motion. Now imagine having to do it in reverse: without looking
at the shade, you must choreograph the sequence of twists around each joint
that would send the shade along a straight path. The trigonometry is
frightfully complicated. But your arm is an architect’s lamp, and your brain
effortlessly solves the equations every time you point.”[11]

Apparently much of this sort of control is acquired in
utero
.

Can Pinker’s metaphor of equation-solving be
reconciled with the idea of reorganization?

The fetus gaining control of his limbs starts out wildly,
just thrashing in all directions. But there are built-in preexisting
selectors at each level which tell each next lower level control system whether
its reference standards are getting better or worse, and it remembers. So
eventually, when a higher level center is controlling the perception Salt
Cellar in Hand, say, the lower level centers solve their equations with a
minimum of trial and error. The hand smoothly, “effortlessly”
reaches out and picks up the salt cellar. But there’s always some trial
and error involved, every time. We just stop noticing it.

How’s that?

Best, Ted

[from Tracy B. Harms (2009-08-04 15:37 Pacific)]

My finger points here: "Now imagine having to do it in reverse:
without looking at the shade, you must choreograph the sequence of
twists around each joint that would send the shade along a straight
path."

The error is the idea that the "frightfully complicated" trigonometry
is what is controlled, and that this occurs "without looking at the
shade." Instead, (the position of) the shade *is* looked at. Indeed,
it's the primary thing under control. The other angles are not
(individually) controlled, as would be seen by the way modest
interferences with any given joint would be compensated for by the
action of the arm as a whole.

Tracy

···

On Tue, Aug 4, 2009 at 12:26 PM, Ted Cloak<tcloak@unm.edu> wrote:

[From Ted Cloak (2009.08.04.1318 MST)]

Whoa! I just flashed on the big mistake, PCT-wise, in Pinker�s metaphor;
which I think beautifully illustrates the limitation of conventional
cognitive neuroscience as a behavior-explainer.

�...

[Tracy B. Harms (2009-08-04 15:37 Pacific)]

My finger points here: "Now imagine having to do it in reverse:
without looking at the shade, you must choreograph the sequence of
twists around each joint that would send the shade along a straight
path."

The error is the idea that the "frightfully complicated" trigonometry
is what is controlled, and that this occurs "without looking at the
shade." Instead, (the position of) the shade *is* looked at. Indeed,
it's the primary thing under control. The other angles are not
(individually) controlled, as would be seen by the way modest
interferences with any given joint would be compensated for by the
action of the arm as a whole.

Tracy

···

On Tue, Aug 4, 2009 at 12:26 PM, Ted Cloak<tcloak@unm.edu> wrote:

[From Ted Cloak (2009.08.04.1318 MST)]

Whoa! I just flashed on the big mistake, PCT-wise, in Pinker�s metaphor;
which I think beautifully illustrates the limitation of conventional
cognitive neuroscience as a behavior-explainer.

�...

[From Ted Cloak (2009.08.04.1700 MST)]

That's exactly what I had in mind.
Ted

[From Rick Marken (2009.08.04.1800)]

Ted Cloak (2009.08.04.1318 MST)-

Whoa! I just flashed on the big mistake, PCT-wise, in Pinker’s metaphor;
which I think beautifully illustrates the limitation of conventional
cognitive neuroscience as a behavior-explainer.

Tracy B. Harms (2009-08-04 15:37 Pacific)–

The error is the idea that the “frightfully complicated” trigonometry

is what is controlled, and that this occurs "without looking at the

shade."

Great observation Ted and Tracy. Just to supplement your point I would like to note that a psychologist named Franz Mechsner developed an ingenious experimental demonstration of the lack of feasibility of computation of output as a way of producing behavior like that described in Pinker’s metaphor. It involves making two flags move in syncrhrony using non-synchronous handle movements. There is a description of Mechsner’s experimental set-up as well as a working control model that produces the behavior observed in this experiment at http://www.mindreadings.com/Coordination.html. The behavior produced by the model, which matches that produced by the subjects, could not possibly have been produced by a “computed output” system.

Best

Rick

···

Richard S. Marken PhD
rsmarken@gmail.com

[From Bill Powers (2009.08.04.2204 MDT)]

Ted Cloak (2009.08.04.1318 MST) –

TC: Whoa! I just flashed on the
big mistake, PCT-wise, in Pinker’s metaphor; which I think beautifully
illustrates the limitation of conventional cognitive neuroscience as a
behavior-explainer.

BP: Check out demo 8-3 in LCS3. It’s the Little Man with better graphics.
You can move a target around in 3-space and the arm and hand will track
it. The arm has 14 degrees of freedom, of which three are used by the
level that does the tracking. There are no computations of joint angle,
either forward or backward.
It’s interesting to put your finger on the tip of your nose, then reach
out and touch a corner of the computer screen or any other handy target.
Do this a few times, then close your eyes, move your finger from nose to
the target, and open your eyes.
I’m off about an inch at arm’s length. I’m also off the tip of my nose by
some amount, too, when I go back and forth several times with my eyes
shut.
Actually, an inch of error at arm’s length isn’t bad. But pay attention
to how you do it. In my case, I don’t do it by adjusting joint angles; I
do it by imagining where the tip of the finger is. I have a sort of image
of my whole arm and the space it’s in, and I control that image. With my
eyes shut, the only way I can estimate where my finger is is from
sensing the current joint angles. That’s not very accurate, but
it’s more accurate than I expected. This shows about how much can be
expected from model-based control. Ordinary negative feedback control of
perception is far more accurate.

There seems to be a spatial map in the head in which visual images and
kinesthetic sensations are adjusted to give about the same perceptions.
In experiments with vision, various means have been used to distort this
map, like the famous one with prisms. A person can, with much practice,
learn to ride a bicycle again while wearing the prism glasses, but it
takes a lot of practice. One of the funny bits about the experiment was
that when it was over, the bicycle rider gave the glasses back to the
experimenter and fell off the bicycle. It took about as long to
recalibrate the map while going back to normal.

If a disturbance is applied to the arm when you reach out, you’ll be off
by a lot more when your eyes are closed. This was especially true in the
experiments done by Isaac Kurtzer at Brandeis, in which the subject sat
in a room that could be rotated. In reaching radially outward, the arm
was subject to a sideways Coriolis force that depended on the speed of
rotation. No skin pressure was sensed, of course; the arm just didn’t go
the way the subject wanted. Initially, the disturbing force simply caused
the arm to deviate. With eyes-open observation of the result of each
reach, subjects eventually learned to reach straight out toward the
target with their eyes closed. Of course after that, when the room
rotation was stopped, they deviated the other way!

TC: Can Pinker’s metaphor of
equation-solving be reconciled with the idea of reorganization?

The fetus gaining control of his limbs starts out wildly, just thrashing
in all directions. But there are built-in preexisting selectors at
each level which tell each next lower level control system whether its
reference standards are getting better or worse, and it remembers. So
eventually, when a higher level center is controlling the perception Salt
Cellar in Hand, say, the lower level centers solve their equations with a
minimum of trial and error. The hand smoothly, “effortlessly” reaches out
and picks up the salt cellar. But there’s always some trial and error
involved, every time. We just stop noticing it.

Look at Demo 8-1, ArmControlReorg. Here we have an arm with 14 degrees of
freedom which starts out with 14 incomplete control systems. Each control
system’s output is connected to ALL of the joint angles through a total
of 196 weights. There are 14 disturbances acting on the joint angles, and
there are 14 reference signals, five of which can be set to vary in
several different patterns. The weightings all start out at zero, and the
reorganizing system, using only the information in the error signals,
gradually does an E. coli reorganization on all 14 systems that ends up
with all joints under good control. You can pause the reorganization at
any time and see how good the control is, then restart it and see the
control improve some more.

An interesting undocumented feature of this demo is that you can turn off
the reference signal variations and let the system learn control simply
by learning to oppose the disturbances. After learning has neared an
asymptote, you can turn off the disturbances and turn on a smooth pattern
of reference signals, and control will be just as good, with no further
reorganization. This works the other way, too: train with varying
reference signals only, and observe that the arm will resist disturbances
just as well as if trained with the disturbances acting.

This is a direct demonstration of learning control systems, not
behaviors.

Pinker, despite his facility with language, is nowhere near understanding
any of this.

Best,

Bill P.

[Shannon Williams (2009.08.04.2330 CST)]

[From Ted Cloak (2009.08.04.1318 MST)]

But there�s always some trial and error involved, every time.
We just stop noticing it.

How�s that?

That is wonderful! I am thinking that too. I think that you should
send Pinker a note. The way that you word it here, Pinker can
bootstrap himself into PCT. He can back into it as a practical
matter because only PCT provides a way for this to work.

[Ted Cloak (2009.08.04.2254 MST)]

[Shannon Williams (2009.08.04.2330 CST)]

[From Ted Cloak (2009.08.04.1318 MST)]

But there's always some trial and error involved, every time.
We just stop noticing it.

How's that?

That is wonderful! I am thinking that too. I think that you should
send Pinker a note. The way that you word it here, Pinker can
bootstrap himself into PCT. He can back into it as a practical
matter because only PCT provides a way for this to work.

You read my mind. Stay tuned.
Ted

This week's PCT quiz:

"The Queen took a large spoonful of soup and displayed her fine person and
graceful manner, in alternately looking at the company in various parts of
the hall and ordering several kinds of seasoning to be brought to her, by
which she fitted her supper to her taste. When this was accomplished, her
Majesty exhibited to the admiring spectators the magnificent spectacle of a
great queen swallowing her royal supper in a single spoonful, all at once.
This was all performed like perfect clockwork, not a feature of her face,
nor a motion of any part of her person, especially her arm and her hand
could be criticized as out of order."

Who was the Queen?
Who wrote this encomium?

Ted

···

-----Original Message-----
From: Ted Cloak [mailto:tcloak@unm.edu]
Sent: Tuesday, August 04, 2009 5:05 PM
To: 'Control Systems Group Network (CSGnet)'
Subject: RE: Reorganization and Trial-and-Error - WHOA!

[Tracy B. Harms (2009-08-04 15:37 Pacific)]

My finger points here: "Now imagine having to do it in reverse:
without looking at the shade, you must choreograph the sequence of
twists around each joint that would send the shade along a straight
path."

The error is the idea that the "frightfully complicated" trigonometry
is what is controlled, and that this occurs "without looking at the
shade." Instead, (the position of) the shade *is* looked at. Indeed,
it's the primary thing under control. The other angles are not
(individually) controlled, as would be seen by the way modest
interferences with any given joint would be compensated for by the
action of the arm as a whole.

Tracy

On Tue, Aug 4, 2009 at 12:26 PM, Ted Cloak<tcloak@unm.edu> wrote:

[From Ted Cloak (2009.08.04.1318 MST)]

Whoa! I just flashed on the big mistake, PCT-wise, in Pinker�s metaphor;
which I think beautifully illustrates the limitation of conventional
cognitive neuroscience as a behavior-explainer.

�...

[From Ted Cloak (2009.08.04.1700 MST)]

That's exactly what I had in mind.
Ted

[From Rick Marken (2009.08.12.1315)]

···

On Wed, Aug 12, 2009 at 12:34 PM, Ted Cloak<tcloak@unm.edu> wrote:

This week's PCT quiz:

"The Queen took a large spoonful of soup and displayed her fine person and
graceful manner, in alternately looking at the company in various parts of
the hall and ordering several kinds of seasoning to be brought to her, by
which she fitted her supper to her taste. When this was accomplished, her
Majesty exhibited to the admiring spectators the magnificent spectacle of a
great queen swallowing her royal supper in a single spoonful, all at once.
This was all performed like perfect clockwork, not a feature of her face,
nor a motion of any part of her person, especially her arm and her hand
could be criticized as out of order."

Who was the Queen?
Who wrote this encomium?

Gosh, it's so well written. Here's three guesses:

Queen Writer
---------------------------------------------------
Cleopatra Gibbon
Victoria Disraeli
Red Queen Carroll

Probably all wrong.

Best

Rick

--
Richard S. Marken PhD
rsmarken@gmail.com

[From Bill Powers (20-09.078.12.1544)]

This week’s PCT quiz:

Who was the Queen?

Who wrote this encomium?

**[

John Adams - Google Books Result](John Adams - David McCullough - Google Books)**
by David G. McCullough -
2001 - Biography & Autobiography - 751 pages
The Queen took a large spoonful of soup and displayed her fine person
and graceful manner
, in alternately looking at the company in various
parts of the isbn:0684813637 - Google Search

Sorry, I cheated and asked Google.

How the devil did you ever come across this obscurity?

Best,

Bill P.

···

At 01:34 PM 8/12/2009 -0600, Ted Cloak wrote:

[From Ted Cloak (2009.08.12.1714 MST)]

···

++++++++++++++++++++++++++++++++

[From Bill Powers (20-09.078.12.1544)]

At 01:34 PM 8/12/2009 -0600, Ted Cloak wrote:

This week’s PCT quiz:
Who was the Queen?
Who wrote this encomium?

[John

Adams - Google Books Result](http://books.google.com/books?id=E9TOxypjZY4C&pg=PA203&lpg=PA203&dq="The+Queen+took+a+large+spoonful+of+soup+and+displayed+her+fine+person+and+graceful+manner+…&source=bl&ots=4gfFoyxZur&sig=vqsY3SUTlkW60vv7f1GLYHMA1zo&hl=en&ei=CDeDSt_HOo2CtgeZhKzGCg&sa=X&oi=book_result&ct=result&resnum=1)

by David G. McCullough - 2001 - Biography &
Autobiography - 751 pages
The Queen took a large spoonful of soup and displayed her fine person and
graceful manner
, in alternately looking at the company in various parts of
the books.google.com/books?isbn=0684813637

Sorry, I cheated and asked Google.

How the devil did you ever come across this obscurity?

Best,
Bill P.

+++++++++++++++++++++++++++++++++++++

Actually, my book club happens to be reading McCullough for next
Wednesday, and the last sentence of the quote – “This was
all performed like perfect clockwork, not a feature of her face, nor a motion
of any part of her person, especially her arm and her hand could be criticized
as out of order." -hit me right between the eyes. (Note to self: Send this to
Pinker.)

As you found out,

John Adams was the writer (in his autobiography, many years
after the royal dinner when he was Minister Plenipotentiary of the Continental
Congress to the French Crown.)

Marie Antoinette was the Queen.

Thanx to Rick for his ingenious guesses.

Regards to all,

Ted