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- Message-ID: <9209021922.AA29054@chroma.dciem.dnd.ca>
- Newsgroups: bit.listserv.csg-l
- Date: Wed, 2 Sep 1992 15:22:29 EDT
- Sender: "Control Systems Group Network (CSGnet)" <CSG-L@UIUCVMD.BITNET>
- From: mmt@BEN.DCIEM.DND.CA
- Subject: Re: Exploration and Reorganization
- Lines: 61
-
- [Martin Taylor 920902 14:30]
- (Rick Marken 920902.0930)
-
- >I was not clear. I think of "exploration" and "reorganization" as words
- >describing potential mechanisms underlying an observed behavior; I think
- >of them as descriptions of models.
-
- Well, clarity, like everything else, is in the eye of the beholder, and
- in the case of writing, the writer beholding(?) sees differently from most
- others. I thought I was clear, too. But the rat example clearly fits
- one view of exploration, which was not what I had intended.
-
- > For example, when a rat is placed in a test chamber
- >it "explores" -- it sniffs around, climbs the walls, pushes on stuff, etc.
- >It produces a lot of changing perceptions for itself; I think many people
- >would describe this as exploration.
-
- Yes, they would, but it wasn't really what I meant, unless neither of your
- proposed explanations apply.
-
- >Now, what is causing this behavior?
- >One explanation is that it is caused by systematic variation in the
- >rats' references for various perceptions, this variation being caused by a
- >higher order system trying to achieve its own perceptual goal (which
- >might be verbally described as "a perception of high familiarity").
- >This explanation says that the exploration we see is a result of regular,
- >systematic control processes -- and this could be tested using versions
- >of the test for the controlled variable.
- >
- I hadn't thought of this possibility. It comes close to an idea I had very
- many years ago, that organisms control to maintain a preferred level of
- variability in perception at all levels of abstraction. If things are
- too familiar to the rat, look for something new. If you are put in a
- sensory isolation chamber, turn up the gain in your sensory systems so that
- the noise can be interpreted as perceiving something. At a high level,
- don't allow yourself to get bored.
- >
- >Another possible PCT explanation of the SAME behavior would be that it
- >is the result of reorganization. This explanation would be particularly
- >plausible if we knew that the rat had not eaten for a day before being
- >placed in the test cage. If the "exploratory behavior" is the result
- >of reorganization then we would expect to see the variability of the
- >behavior gradually eliminated as control of some particular aspect of
- >the enviroment had effects that reduced intrinsic error.
-
- This would also account for the actions observed by a third party.
-
- My account ties in with the alerting function discussion. When there are
- "spare" degrees of freedom that could be used for control, and are not
- because all the references are reasonably well satisfied, then some are
- available for actions that find out "what is there." This is not to satisfy
- any reference for reducing hunger (or "thirst for knowledge"), but to
- discover the perceptual results of some action. That discovery permits the
- assignment of the correct sign to the output that was/led to the action,
- for a later occasion when the ECS in question has a reference that it must
- satisfy with its percept. Reorganization is a consequence of exploration,
- in this view, and it happens at zero gain.
-
- I hope this is clear, but even if it is, the clarity may well be an illusion.
-
- Martin
-