Abstract: Objective To explore the effect of oxygen inhalation on auditory sensory gating P50 in healthy human brain. Methods 28 healthy male academician right-handed were included. They were divided into control group (n=12) and experiment group (n=16) according to the random numerical table, and blinded about groups. The subjects inhaled pure oxygen in the experiment group, and air in the control group through a mask for 60 min. The electroencephalograph was recorded while an auditory paired-click sensory gating test was conducted during 4 study periods: before inhalation (pre0), inhale for 20 min (Oxy20) and 50 min (Oxy50), and 30 min after inhalation (post30). The latency and amplitude (S1-S2) of auditory sensory gating P50 were calculated. Results The latencies of P50 from S1 were stable in each group (P>0.7), and the latency of Oxy50 was shorter in the experiment group than in the control group (P<0.05). The latencies from S2 were stable in each group (P>0.30), and there was no significant difference between groups in all the time points (P>0.05). The amplitudes of (S1-S2) of P50 were stable in the control group (P=0.70), and was higher on Oxy20 (P=0.04) and Oxy50 (P=0.02) than post30 in the experiment group. There was no difference between the groups in all the time points (P>0.05). Conclusion Oxygen inhalation may be helpful to shorten the active time to stimulate, and trend to enhancing the amplitude of P50.

Key words: oxygen inhalation, auditory sensory gating, P50