Neurophysiological predictions of a two-pathway informon theory of neural conditioning.
According to the informon theory there must be variable and fixed synapses in a neurone for conditioning to occur. For a variable synapse to behave like an informon pathway its conductivity needs to depend only on the average values of its presynaptic potential and of the internal state of the neurone. Eight predictions are made about the detailed functioning of such a synapse. In a minimal hypothesis all fixed synapses are inhibitory; but sign reversals are considered. Let one unit A in the receptive field of a neurone drive it through a fixed synapse, and all other units, e.g. B, drive variable synapses; then the theory predicts that the conductivity of the B synapse becomes proportional to the mutual information function between the signals at A and B; so inputs which tend to occur with the A signal become connected positively to the neurone. Applied to visual pathways this principle leads to the formation of edge and grating detectors. If X and Y cells excite variable and fixed synapses respectively, simple and complex cells should be driven by both X and Y cells, the latter being inhibitory. The two-pathway theory resolves two apparent conflicts between experimental facts.
D003213:Conditioning, Psychological / Q000502:physiology*; D007257:Information Theory; D008959:Models, Neurological; D009433:Neural Inhibition; D009434:Neural Pathways / Q000502:physiology; D011712:Pyramidal Tracts / Q000502:physiology; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission; D014793:Visual Cortex / Q000502:physiology