When an afferent stimulus is repeated, but not attended to, the synapses
involved habituate. This occurs on the presynaptic side and appears to
involve depletion of Ca++ in the extracellular fluid at the synapse. (Ca++
is required for vesicles to attach and release their contents.) On the
other hand, if the stimulus is attended to, so that the post-synaptic side
is depolarized to some degree, conditioning occurs. Is the Ca++
concentration maintained in the synapse during conditioning? Or is the
depletion more than counterbalanced by the conditioning process? This is a
significant issue if one is trying to simulate learning processes in mass
action models.
Cheers,
--
Harry Erwin
Internet: erwin at trwacs.fp.trw.comherwin at cs.gmu.edu
Working on Freeman nets....
