[Effect of acute hypoxia on the EEG and neuronal pulse activity of various brain structures in rats].

The initial phase of hypoxia effect involves activation of the EEG (2000---6000 m) and unit impulse activity (7500--10 000 m). The 7500--10 000 m induced a change towards a predominant slow rhythm of the delta-type while the unit impulse activity gradually diminished, the cortical neurons displaying a higher hypoxia sensitivity and an earlier suppression than the cells of the hypothalamus and the medulla. In all phases of the hypoxia effect the EEG waves showed a greater sensitivity to the rapid peripheral signals than the unit impulse activity of the cortex and other brain structures.