[Reflection of quantitative parameters of a series of nonreinforced heteromodal signals in cortical evoked potentials].

Systematic presentation to dogs of series, standard in number of sound, electro-cutaneous or visual stimuli, leads to a development of U-shaped dependence of cortical evoked potentials (EPs) on the stimulus position in the series. This indicates that in the dog's CNS an estimation is formed of the quantitative structure of the applied series, shaped in a similar way for stimuli of all of these modalities. Singling-out of the stimulus quantitative property results from a simple repetition of the series without any reinforcement, i.e. in the course of perceptual learning. Dependence of the EP on its position in the series appears earlier and with a greater stability in the projection of the stimulus modality than in cortical areas of other modalities. The dependence of the EP on signal position in a series of unimodal stimuli is relatively rapidly reproduced following a transition to similar series of other modalities. This suggests a possibility of transfer of the estimation of quantitative series structure from one modality analyser to another one.