[Interhemispheric relations of the cat visual cortex following unilateral polarization of the secondary visual area]

In 40 anesthetized cats, evoked potentials following light flashes during unilateral polarization of the secondary cortical visual area with DC anode (2-10 mcA) were studied in symmetrical centers of the 17th and 18th fields. Four phases of interhemisphere interrelationships between the 18th field's symmetrical centers were shown: 1 -- extracallosal phase of synergic depression; 2 -- callosal phase of dominant interrelationships; 3 -- callosal phase of synergic depression; 4 -- callosal-extracallosal phase of dominant interrelationships. In symmetrical centers of the 17th field, the only 1 extracallosal phase of synergic depression was observed during which the transcallosal modulation of nervous processes occurred. The data obtained are interpreted from the standpoint of the role of dominanta in interhemisphere interrelationships.