"Charles" <nospam[at]nospam.com
- quote -

YES!

At least as it pertains to humans of an age to wear glasses.

At birth, humans show a wider variety of refractive error than they do at
age 1 or 2, demonstrating that there is certainly an "emmetropization"
process that leads to a smaller standard deviation, concentrating the
distribution around +1.00 D (a "kurtotic" distribution, more of a "spike"
than a "normal" curve.)

Presumably this is the period in chickens and "primates" where inappropriate
lenses CAN influence refractive error and likely would in humans as well. So
doctors are justifiably stingy with corrective lenses at that age.

But after age 6 or 8, when myopia starts, humans begin to diverge again (the
standard deviation INCREASES) and the best evidence comparing groups shows
that accommodation is not likely to be the mechanism - wearing or not
wearing corrective lenses seems to make no difference. Uncorrected hyperopes
don't get less hyperopic, and myopes (who accommodate LESS) tend to get more
myopic.

-MT

Dom <dont[at]spam.me> wrote:

- quote -

Charles-

Here's a good resource for you. It lays out the current ('02)
thinking on myopiagenesis, the status of testing of proposed
intervention methods, and a set of conclusions based on known data.

They're saying what everybody *else* on this board says: most myopes
can take off their (mild plus) glasses for near work, Atropine can
help some people, used /with/ bifocals (reduced minus -- nobody else
says plus), and that Pirenzepine is pretty effective in chickens.

http://www.pubmedcentral.gov/article...&artid=1123161

OR: http://snipurl.com/l89n

HTH,

Neil
--
Live simply so that others may simply live

Charles wrote:
- quote -

Yes.

The best current theory, as I understand it, is that hyperopic blur at
the retina stimulates growth of the eyeball.

Dom

otisbrown[at]pa.net wrote:
- quote -

Errr, now I'm having problems making my direct
correlations between posts. Here we're talking about
the "natural eye". Last time we were talking about
the "fundamental eye". Below you qualify the
"natural eye" as the "living eye" (as opposed to
dead?).

You also speak of "primates" (held in cages) and
refer to "ALL PRIMATE DATA".

(prmt) A mammal of the order Primates, which
includes the anthropoids and prosimians, characterized
by refined development of the hands and feet, a
shortened snout, and a large brain.

I got the impression in some posts that this group
was restricted to monkeys and chimpanzees (which
I understand to be different animals) and not restricted
in other posts.

Could you provide a small glossary of all these kinds
of eyes and terminology and then use them consistently
so we can follow along? I am an engineer (software) and
have found it of some importance in discussions to use
consistent and defined terminology so that all the participants
are discussing the same thing...

-Quick

Dear DrG,

A majority-opinion statement from a person who is
not an engineer, and does not understand
the dynamic behavior of the living eye.

Charles will have to make up his own
mind accordingly.

Otis

I don't know what kind of engineer Charles is, but I give him a whole
lot more credit for intelligence than you do.

DrG

Dear Charles,

Subject: Modeling the natural eye's behavior.

I am not certain what type of engineering you are in to.

But, if you designed a sophisticated auto-focused camera,
you would find that:

1. You place a minus lens on a population of these
auto-focused cameras, and the "living eye" camera
will change its refractive state to:

2. An applied minus lens.

3. An an applied "nearer" enviroment.

These are scientific answers to what is directly
measured. You are jumping to conclusions. The
natural eye simply has this proven and expected
characteristic.

It would help a lot if you used the term "refractive status",
to avoid the intense bias that exists with these ODs.

They keep on providing knee-jerk responses to the
wrong questions.

But you are right. The refractive state of the
primate eye (change of) is highly correlated
to a "shift" in its visual enviroment (in diopters.)
(Primate of adolescent eyes. This was absolutly
direct control, where the eye were placed in
a "box" with good illumination, were the
other primates were kept in cages.
Standard "drops" were used for the
refractive-state measurement.

Shortly, you will be told that you must ignore
ALL PRIMATE DATA, because the
majority-opinion ODs do not like
you getting the correct and accurate
idea about the natural (living eye's) proven
behavior.

Enjoy or engineering analysis.

Best,

Otis

Scott Seidman <namdiesttocs[at]mindspring.com> wrote:

- quote -

Otis, Engineer: http://nbeener.com/Otis_Engineer.jpg
--
Live simply so that others may simply live

Thanks for all the replies. So, just for my understanding, are these
statements true?

1) The devlopment of myopia is correlated with close work (e.g. college
profs and computer programmers are more likely to develop it than
otherwise similar people who work outdoors).

2) However, it does not appear to be simplistically related to the
amount of muscular effort exerted by the muscles of the eye - and the
exact mechanism is not precisely known at this time.

"Mike Tyner" <mtyner[at]mindspring.com> wrote in
news:J5Ktf.3045$M%4.1388[at]newsread3.news.atl.earthlink.net:

- quote -

Absolutely not. Having learned the hard lessons, like the brittle state
of steel under cold in the Titanic, engineers understand well that things
behave differently under different conditions.

Just like I don't let the docs Otis lists in the "second opinion" column
leave an impression of what an OD does for a living, please don't assume
that Otis represents many engineers. Logical flaws are logical flaws,
regardless of discipline.

--
Scott
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