Dynamics of the impulse activity of neurons of the neocortex of monkeys in a visual recognition task after brief oxygen deprivation.

A model of brief oxygen supply disruption was created in monkeys trained to a delayed visual spatial choice. A substantial reorganization of the impulse activity of neurons of the visual and prefrontal cerebral cortex, accompanied by disturbances in behavioral reactions, was observed during brief hypoxia (2.5 min); the motor reaction was not restored for several hours in the monkeys during a delayed visual spatial choice. The reorganization of the activity consisted in the appearance of successive phases of hyperactivation and inhibition. The frequency of the impulse activity in the phase of hyperactivation was higher in prefrontal cortex neurons. Successive phases of inhibition and hyperactivation were also identified in the posthypoxic period of restoration in the structure of the activity. The duration of the posthypoxic inhibition and the ratio of the frequencies of posthypoxic hyperactivation to the baseline frequency in the reactions of prefrontal cortex neurons was substantially greater than in the neurons of the visual cortex.