🚀 go-pugleaf

Oliver Sparrow (ohgs@chatham.demon.co.uk) wrote:
: ...
: The prime issue is that of the objective function: how does the system
: "know" when it is doing better or worse? In control theory terms, what
: constitutes the error feed back; not least when what is being detected is
: discontinuous and non-linear, in the sense of being part of both the 
: detection and sensorium sides of the equation.

For olfactory processing, this seems to involve the norepi system. I
haven't addressed that here, since it's about four stages down the road:
1. model the connectivity of the OB and PC in greater detail than
   has so far been done. Freeman's models of the OB are relatively simple,
   and my extension has not been towards the biology. I have to remedy
   that.
2. study the coherent states that develop. What is required to
   full-blown coherence? Are most such states transients?
3. examine the process by which the components of the olfactory
   system communicate. Bandwidth is key. 
4. And then address training. (Skinner has done work on the biology
   here). 

: I have suggested elsewhere that an important element is a "!" detector: that
: which detects conditions in some way and says "! Note this! Learn this!" such
: that certain states become re-inforced. If the system which is being 
: strengthened itself plays a part in the "!" process, then we can see (vaguely)
: how this might bootstrap itself into a state from which higher-order patterns
: might merge.

It's the norepinephrinergic system for the olfactory sense. It reverses
the habituation of excitatory cortico-cortical connections. That causes
stp and ltp for cc connections involved in the patterns present. Here,
we're dealing with the reticular formation of the pons and medulla (locus
coeruleus and lateral tegmental cell system). Each NE neuron in those
areas projects to diverse areas of the brain, so you're basically dealing
with a 'fire alarm' system. It's not quite as bad as that, since it gets
triggered quite frequently (at least once every time you have an orientation
reflex). It seems to react nonspecifically to novelty.

--
Harry Erwin
Internet: herwin@gmu.edu 
Working on Katchalsky nets....