title: Changes in the pattern reversal visual evoked potential as a function of inspired nitrous oxide concentration.
abstract: The VEP to pattern displacement was measured at different levels of inspired N2O concentrations in air in 10 normal subjects. The inspired concentrations were 10, 20, 30 and 40% N2O. Expired CO2 concentrations were also measured. Ten normal controls went through the same procedure but breathed air on each trial rather than N2O. The results showed a significant decrease at 10%, almost at 20% and again significant at 30% and 40% for the amplitude of the N65-P95 wave. The P95-N125 wave was more resistant--10% was not significant, 20% was again nearly significant and 30% and 40% were significant. There were no latency changes. Because of the wider variance between group comparisons there was a significant reduction at 40% only for the N65-P95 wave and no significant difference for the P95-N125 wave. There was some evidence that the amplitude of the early components was still significantly reduced after the end of the experiment.
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000187:drug effects*; D006801:Humans; D008297:Male; D009609:Nitrous Oxide / Q000494:pharmacology*; D010100:Oxygen / Q000494:pharmacology
chemical_list: D009609:Nitrous Oxide; D010100:Oxygen