Effect of Nitrous Oxide on the Auditory Evoked Response in Man

Abstract

IN human pharmacology there are few objective indicators of sedative drug action. Consequently, the development of neurophysiological measures sensitive to such drugs would give this aspect of psychopharmacology a firmer quantitative basis. A powerful neurophysiological technique in man is that of evoking electroencephalographic responses which can be recorded from the scalp by using recent computer techniques which perform the necessary averaging computations. The wave-form obtained by visual, auditory or somato-sensory stimulation has been regarded as divisible into components of short latency arising from the “specific” cortical receiving areas and “non-specific” potentials of longer latency. The latter are widely distributed, being detectable over much of the scalp including the vertex¹.